Initial import

1 files changed, 6572 insertions, 0 deletions

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
new file mode 100644
index 000000000..29f94f6f0
--- /dev/null
+++ b/tools/lib/traceevent/event-parse.c
@@ -0,0 +1,6572 @@
+/*
+ * Copyright (C) 2009, 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License (not later!)
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not,  see <http://www.gnu.org/licenses>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  The parts for function graph printing was taken and modified from the
+ *  Linux Kernel that were written by
+ *    - Copyright (C) 2009  Frederic Weisbecker,
+ *  Frederic Weisbecker gave his permission to relicense the code to
+ *  the Lesser General Public License.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <ctype.h>
+#include <errno.h>
+#include <stdint.h>
+#include <limits.h>
+
+#include <netinet/ip6.h>
+#include "event-parse.h"
+#include "event-utils.h"
+
+static const char *input_buf;
+static unsigned long long input_buf_ptr;
+static unsigned long long input_buf_siz;
+
+static int is_flag_field;
+static int is_symbolic_field;
+
+static int show_warning = 1;
+
+#define do_warning(fmt, ...)				\
+	do {						\
+		if (show_warning)			\
+			warning(fmt, ##__VA_ARGS__);	\
+	} while (0)
+
+#define do_warning_event(event, fmt, ...)			\
+	do {							\
+		if (!show_warning)				\
+			continue;				\
+								\
+		if (event)					\
+			warning("[%s:%s] " fmt, event->system,	\
+				event->name, ##__VA_ARGS__);	\
+		else						\
+			warning(fmt, ##__VA_ARGS__);		\
+	} while (0)
+
+static void init_input_buf(const char *buf, unsigned long long size)
+{
+	input_buf = buf;
+	input_buf_siz = size;
+	input_buf_ptr = 0;
+}
+
+const char *pevent_get_input_buf(void)
+{
+	return input_buf;
+}
+
+unsigned long long pevent_get_input_buf_ptr(void)
+{
+	return input_buf_ptr;
+}
+
+struct event_handler {
+	struct event_handler		*next;
+	int				id;
+	const char			*sys_name;
+	const char			*event_name;
+	pevent_event_handler_func	func;
+	void				*context;
+};
+
+struct pevent_func_params {
+	struct pevent_func_params	*next;
+	enum pevent_func_arg_type	type;
+};
+
+struct pevent_function_handler {
+	struct pevent_function_handler	*next;
+	enum pevent_func_arg_type	ret_type;
+	char				*name;
+	pevent_func_handler		func;
+	struct pevent_func_params	*params;
+	int				nr_args;
+};
+
+static unsigned long long
+process_defined_func(struct trace_seq *s, void *data, int size,
+		     struct event_format *event, struct print_arg *arg);
+
+static void free_func_handle(struct pevent_function_handler *func);
+
+/**
+ * pevent_buffer_init - init buffer for parsing
+ * @buf: buffer to parse
+ * @size: the size of the buffer
+ *
+ * For use with pevent_read_token(), this initializes the internal
+ * buffer that pevent_read_token() will parse.
+ */
+void pevent_buffer_init(const char *buf, unsigned long long size)
+{
+	init_input_buf(buf, size);
+}
+
+void breakpoint(void)
+{
+	static int x;
+	x++;
+}
+
+struct print_arg *alloc_arg(void)
+{
+	return calloc(1, sizeof(struct print_arg));
+}
+
+struct cmdline {
+	char *comm;
+	int pid;
+};
+
+static int cmdline_cmp(const void *a, const void *b)
+{
+	const struct cmdline *ca = a;
+	const struct cmdline *cb = b;
+
+	if (ca->pid < cb->pid)
+		return -1;
+	if (ca->pid > cb->pid)
+		return 1;
+
+	return 0;
+}
+
+struct cmdline_list {
+	struct cmdline_list	*next;
+	char			*comm;
+	int			pid;
+};
+
+static int cmdline_init(struct pevent *pevent)
+{
+	struct cmdline_list *cmdlist = pevent->cmdlist;
+	struct cmdline_list *item;
+	struct cmdline *cmdlines;
+	int i;
+
+	cmdlines = malloc(sizeof(*cmdlines) * pevent->cmdline_count);
+	if (!cmdlines)
+		return -1;
+
+	i = 0;
+	while (cmdlist) {
+		cmdlines[i].pid = cmdlist->pid;
+		cmdlines[i].comm = cmdlist->comm;
+		i++;
+		item = cmdlist;
+		cmdlist = cmdlist->next;
+		free(item);
+	}
+
+	qsort(cmdlines, pevent->cmdline_count, sizeof(*cmdlines), cmdline_cmp);
+
+	pevent->cmdlines = cmdlines;
+	pevent->cmdlist = NULL;
+
+	return 0;
+}
+
+static const char *find_cmdline(struct pevent *pevent, int pid)
+{
+	const struct cmdline *comm;
+	struct cmdline key;
+
+	if (!pid)
+		return "<idle>";
+
+	if (!pevent->cmdlines && cmdline_init(pevent))
+		return "<not enough memory for cmdlines!>";
+
+	key.pid = pid;
+
+	comm = bsearch(&key, pevent->cmdlines, pevent->cmdline_count,
+		       sizeof(*pevent->cmdlines), cmdline_cmp);
+
+	if (comm)
+		return comm->comm;
+	return "<...>";
+}
+
+/**
+ * pevent_pid_is_registered - return if a pid has a cmdline registered
+ * @pevent: handle for the pevent
+ * @pid: The pid to check if it has a cmdline registered with.
+ *
+ * Returns 1 if the pid has a cmdline mapped to it
+ * 0 otherwise.
+ */
+int pevent_pid_is_registered(struct pevent *pevent, int pid)
+{
+	const struct cmdline *comm;
+	struct cmdline key;
+
+	if (!pid)
+		return 1;
+
+	if (!pevent->cmdlines && cmdline_init(pevent))
+		return 0;
+
+	key.pid = pid;
+
+	comm = bsearch(&key, pevent->cmdlines, pevent->cmdline_count,
+		       sizeof(*pevent->cmdlines), cmdline_cmp);
+
+	if (comm)
+		return 1;
+	return 0;
+}
+
+/*
+ * If the command lines have been converted to an array, then
+ * we must add this pid. This is much slower than when cmdlines
+ * are added before the array is initialized.
+ */
+static int add_new_comm(struct pevent *pevent, const char *comm, int pid)
+{
+	struct cmdline *cmdlines = pevent->cmdlines;
+	const struct cmdline *cmdline;
+	struct cmdline key;
+
+	if (!pid)
+		return 0;
+
+	/* avoid duplicates */
+	key.pid = pid;
+
+	cmdline = bsearch(&key, pevent->cmdlines, pevent->cmdline_count,
+		       sizeof(*pevent->cmdlines), cmdline_cmp);
+	if (cmdline) {
+		errno = EEXIST;
+		return -1;
+	}
+
+	cmdlines = realloc(cmdlines, sizeof(*cmdlines) * (pevent->cmdline_count + 1));
+	if (!cmdlines) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	cmdlines[pevent->cmdline_count].comm = strdup(comm);
+	if (!cmdlines[pevent->cmdline_count].comm) {
+		free(cmdlines);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	cmdlines[pevent->cmdline_count].pid = pid;
+		
+	if (cmdlines[pevent->cmdline_count].comm)
+		pevent->cmdline_count++;
+
+	qsort(cmdlines, pevent->cmdline_count, sizeof(*cmdlines), cmdline_cmp);
+	pevent->cmdlines = cmdlines;
+
+	return 0;
+}
+
+/**
+ * pevent_register_comm - register a pid / comm mapping
+ * @pevent: handle for the pevent
+ * @comm: the command line to register
+ * @pid: the pid to map the command line to
+ *
+ * This adds a mapping to search for command line names with
+ * a given pid. The comm is duplicated.
+ */
+int pevent_register_comm(struct pevent *pevent, const char *comm, int pid)
+{
+	struct cmdline_list *item;
+
+	if (pevent->cmdlines)
+		return add_new_comm(pevent, comm, pid);
+
+	item = malloc(sizeof(*item));
+	if (!item)
+		return -1;
+
+	if (comm)
+		item->comm = strdup(comm);
+	else
+		item->comm = strdup("<...>");
+	if (!item->comm) {
+		free(item);
+		return -1;
+	}
+	item->pid = pid;
+	item->next = pevent->cmdlist;
+
+	pevent->cmdlist = item;
+	pevent->cmdline_count++;
+
+	return 0;
+}
+
+int pevent_register_trace_clock(struct pevent *pevent, const char *trace_clock)
+{
+	pevent->trace_clock = strdup(trace_clock);
+	if (!pevent->trace_clock) {
+		errno = ENOMEM;
+		return -1;
+	}
+	return 0;
+}
+
+struct func_map {
+	unsigned long long		addr;
+	char				*func;
+	char				*mod;
+};
+
+struct func_list {
+	struct func_list	*next;
+	unsigned long long	addr;
+	char			*func;
+	char			*mod;
+};
+
+static int func_cmp(const void *a, const void *b)
+{
+	const struct func_map *fa = a;
+	const struct func_map *fb = b;
+
+	if (fa->addr < fb->addr)
+		return -1;
+	if (fa->addr > fb->addr)
+		return 1;
+
+	return 0;
+}
+
+/*
+ * We are searching for a record in between, not an exact
+ * match.
+ */
+static int func_bcmp(const void *a, const void *b)
+{
+	const struct func_map *fa = a;
+	const struct func_map *fb = b;
+
+	if ((fa->addr == fb->addr) ||
+
+	    (fa->addr > fb->addr &&
+	     fa->addr < (fb+1)->addr))
+		return 0;
+
+	if (fa->addr < fb->addr)
+		return -1;
+
+	return 1;
+}
+
+static int func_map_init(struct pevent *pevent)
+{
+	struct func_list *funclist;
+	struct func_list *item;
+	struct func_map *func_map;
+	int i;
+
+	func_map = malloc(sizeof(*func_map) * (pevent->func_count + 1));
+	if (!func_map)
+		return -1;
+
+	funclist = pevent->funclist;
+
+	i = 0;
+	while (funclist) {
+		func_map[i].func = funclist->func;
+		func_map[i].addr = funclist->addr;
+		func_map[i].mod = funclist->mod;
+		i++;
+		item = funclist;
+		funclist = funclist->next;
+		free(item);
+	}
+
+	qsort(func_map, pevent->func_count, sizeof(*func_map), func_cmp);
+
+	/*
+	 * Add a special record at the end.
+	 */
+	func_map[pevent->func_count].func = NULL;
+	func_map[pevent->func_count].addr = 0;
+	func_map[pevent->func_count].mod = NULL;
+
+	pevent->func_map = func_map;
+	pevent->funclist = NULL;
+
+	return 0;
+}
+
+static struct func_map *
+find_func(struct pevent *pevent, unsigned long long addr)
+{
+	struct func_map *func;
+	struct func_map key;
+
+	if (!pevent->func_map)
+		func_map_init(pevent);
+
+	key.addr = addr;
+
+	func = bsearch(&key, pevent->func_map, pevent->func_count,
+		       sizeof(*pevent->func_map), func_bcmp);
+
+	return func;
+}
+
+/**
+ * pevent_find_function - find a function by a given address
+ * @pevent: handle for the pevent
+ * @addr: the address to find the function with
+ *
+ * Returns a pointer to the function stored that has the given
+ * address. Note, the address does not have to be exact, it
+ * will select the function that would contain the address.
+ */
+const char *pevent_find_function(struct pevent *pevent, unsigned long long addr)
+{
+	struct func_map *map;
+
+	map = find_func(pevent, addr);
+	if (!map)
+		return NULL;
+
+	return map->func;
+}
+
+/**
+ * pevent_find_function_address - find a function address by a given address
+ * @pevent: handle for the pevent
+ * @addr: the address to find the function with
+ *
+ * Returns the address the function starts at. This can be used in
+ * conjunction with pevent_find_function to print both the function
+ * name and the function offset.
+ */
+unsigned long long
+pevent_find_function_address(struct pevent *pevent, unsigned long long addr)
+{
+	struct func_map *map;
+
+	map = find_func(pevent, addr);
+	if (!map)
+		return 0;
+
+	return map->addr;
+}
+
+/**
+ * pevent_register_function - register a function with a given address
+ * @pevent: handle for the pevent
+ * @function: the function name to register
+ * @addr: the address the function starts at
+ * @mod: the kernel module the function may be in (NULL for none)
+ *
+ * This registers a function name with an address and module.
+ * The @func passed in is duplicated.
+ */
+int pevent_register_function(struct pevent *pevent, char *func,
+			     unsigned long long addr, char *mod)
+{
+	struct func_list *item = malloc(sizeof(*item));
+
+	if (!item)
+		return -1;
+
+	item->next = pevent->funclist;
+	item->func = strdup(func);
+	if (!item->func)
+		goto out_free;
+
+	if (mod) {
+		item->mod = strdup(mod);
+		if (!item->mod)
+			goto out_free_func;
+	} else
+		item->mod = NULL;
+	item->addr = addr;
+
+	pevent->funclist = item;
+	pevent->func_count++;
+
+	return 0;
+
+out_free_func:
+	free(item->func);
+	item->func = NULL;
+out_free:
+	free(item);
+	errno = ENOMEM;
+	return -1;
+}
+
+/**
+ * pevent_print_funcs - print out the stored functions
+ * @pevent: handle for the pevent
+ *
+ * This prints out the stored functions.
+ */
+void pevent_print_funcs(struct pevent *pevent)
+{
+	int i;
+
+	if (!pevent->func_map)
+		func_map_init(pevent);
+
+	for (i = 0; i < (int)pevent->func_count; i++) {
+		printf("%016llx %s",
+		       pevent->func_map[i].addr,
+		       pevent->func_map[i].func);
+		if (pevent->func_map[i].mod)
+			printf(" [%s]\n", pevent->func_map[i].mod);
+		else
+			printf("\n");
+	}
+}
+
+struct printk_map {
+	unsigned long long		addr;
+	char				*printk;
+};
+
+struct printk_list {
+	struct printk_list	*next;
+	unsigned long long	addr;
+	char			*printk;
+};
+
+static int printk_cmp(const void *a, const void *b)
+{
+	const struct printk_map *pa = a;
+	const struct printk_map *pb = b;
+
+	if (pa->addr < pb->addr)
+		return -1;
+	if (pa->addr > pb->addr)
+		return 1;
+
+	return 0;
+}
+
+static int printk_map_init(struct pevent *pevent)
+{
+	struct printk_list *printklist;
+	struct printk_list *item;
+	struct printk_map *printk_map;
+	int i;
+
+	printk_map = malloc(sizeof(*printk_map) * (pevent->printk_count + 1));
+	if (!printk_map)
+		return -1;
+
+	printklist = pevent->printklist;
+
+	i = 0;
+	while (printklist) {
+		printk_map[i].printk = printklist->printk;
+		printk_map[i].addr = printklist->addr;
+		i++;
+		item = printklist;
+		printklist = printklist->next;
+		free(item);
+	}
+
+	qsort(printk_map, pevent->printk_count, sizeof(*printk_map), printk_cmp);
+
+	pevent->printk_map = printk_map;
+	pevent->printklist = NULL;
+
+	return 0;
+}
+
+static struct printk_map *
+find_printk(struct pevent *pevent, unsigned long long addr)
+{
+	struct printk_map *printk;
+	struct printk_map key;
+
+	if (!pevent->printk_map && printk_map_init(pevent))
+		return NULL;
+
+	key.addr = addr;
+
+	printk = bsearch(&key, pevent->printk_map, pevent->printk_count,
+			 sizeof(*pevent->printk_map), printk_cmp);
+
+	return printk;
+}
+
+/**
+ * pevent_register_print_string - register a string by its address
+ * @pevent: handle for the pevent
+ * @fmt: the string format to register
+ * @addr: the address the string was located at
+ *
+ * This registers a string by the address it was stored in the kernel.
+ * The @fmt passed in is duplicated.
+ */
+int pevent_register_print_string(struct pevent *pevent, const char *fmt,
+				 unsigned long long addr)
+{
+	struct printk_list *item = malloc(sizeof(*item));
+	char *p;
+
+	if (!item)
+		return -1;
+
+	item->next = pevent->printklist;
+	item->addr = addr;
+
+	/* Strip off quotes and '\n' from the end */
+	if (fmt[0] == '"')
+		fmt++;
+	item->printk = strdup(fmt);
+	if (!item->printk)
+		goto out_free;
+
+	p = item->printk + strlen(item->printk) - 1;
+	if (*p == '"')
+		*p = 0;
+
+	p -= 2;
+	if (strcmp(p, "\\n") == 0)
+		*p = 0;
+
+	pevent->printklist = item;
+	pevent->printk_count++;
+
+	return 0;
+
+out_free:
+	free(item);
+	errno = ENOMEM;
+	return -1;
+}
+
+/**
+ * pevent_print_printk - print out the stored strings
+ * @pevent: handle for the pevent
+ *
+ * This prints the string formats that were stored.
+ */
+void pevent_print_printk(struct pevent *pevent)
+{
+	int i;
+
+	if (!pevent->printk_map)
+		printk_map_init(pevent);
+
+	for (i = 0; i < (int)pevent->printk_count; i++) {
+		printf("%016llx %s\n",
+		       pevent->printk_map[i].addr,
+		       pevent->printk_map[i].printk);
+	}
+}
+
+static struct event_format *alloc_event(void)
+{
+	return calloc(1, sizeof(struct event_format));
+}
+
+static int add_event(struct pevent *pevent, struct event_format *event)
+{
+	int i;
+	struct event_format **events = realloc(pevent->events, sizeof(event) *
+					       (pevent->nr_events + 1));
+	if (!events)
+		return -1;
+
+	pevent->events = events;
+
+	for (i = 0; i < pevent->nr_events; i++) {
+		if (pevent->events[i]->id > event->id)
+			break;
+	}
+	if (i < pevent->nr_events)
+		memmove(&pevent->events[i + 1],
+			&pevent->events[i],
+			sizeof(event) * (pevent->nr_events - i));
+
+	pevent->events[i] = event;
+	pevent->nr_events++;
+
+	event->pevent = pevent;
+
+	return 0;
+}
+
+static int event_item_type(enum event_type type)
+{
+	switch (type) {
+	case EVENT_ITEM ... EVENT_SQUOTE:
+		return 1;
+	case EVENT_ERROR ... EVENT_DELIM:
+	default:
+		return 0;
+	}
+}
+
+static void free_flag_sym(struct print_flag_sym *fsym)
+{
+	struct print_flag_sym *next;
+
+	while (fsym) {
+		next = fsym->next;
+		free(fsym->value);
+		free(fsym->str);
+		free(fsym);
+		fsym = next;
+	}
+}
+
+static void free_arg(struct print_arg *arg)
+{
+	struct print_arg *farg;
+
+	if (!arg)
+		return;
+
+	switch (arg->type) {
+	case PRINT_ATOM:
+		free(arg->atom.atom);
+		break;
+	case PRINT_FIELD:
+		free(arg->field.name);
+		break;
+	case PRINT_FLAGS:
+		free_arg(arg->flags.field);
+		free(arg->flags.delim);
+		free_flag_sym(arg->flags.flags);
+		break;
+	case PRINT_SYMBOL:
+		free_arg(arg->symbol.field);
+		free_flag_sym(arg->symbol.symbols);
+		break;
+	case PRINT_HEX:
+		free_arg(arg->hex.field);
+		free_arg(arg->hex.size);
+		break;
+	case PRINT_INT_ARRAY:
+		free_arg(arg->int_array.field);
+		free_arg(arg->int_array.count);
+		free_arg(arg->int_array.el_size);
+		break;
+	case PRINT_TYPE:
+		free(arg->typecast.type);
+		free_arg(arg->typecast.item);
+		break;
+	case PRINT_STRING:
+	case PRINT_BSTRING:
+		free(arg->string.string);
+		break;
+	case PRINT_BITMASK:
+		free(arg->bitmask.bitmask);
+		break;
+	case PRINT_DYNAMIC_ARRAY:
+		free(arg->dynarray.index);
+		break;
+	case PRINT_OP:
+		free(arg->op.op);
+		free_arg(arg->op.left);
+		free_arg(arg->op.right);
+		break;
+	case PRINT_FUNC:
+		while (arg->func.args) {
+			farg = arg->func.args;
+			arg->func.args = farg->next;
+			free_arg(farg);
+		}
+		break;
+
+	case PRINT_NULL:
+	default:
+		break;
+	}
+
+	free(arg);
+}
+
+static enum event_type get_type(int ch)
+{
+	if (ch == '\n')
+		return EVENT_NEWLINE;
+	if (isspace(ch))
+		return EVENT_SPACE;
+	if (isalnum(ch) || ch == '_')
+		return EVENT_ITEM;
+	if (ch == '\'')
+		return EVENT_SQUOTE;
+	if (ch == '"')
+		return EVENT_DQUOTE;
+	if (!isprint(ch))
+		return EVENT_NONE;
+	if (ch == '(' || ch == ')' || ch == ',')
+		return EVENT_DELIM;
+
+	return EVENT_OP;
+}
+
+static int __read_char(void)
+{
+	if (input_buf_ptr >= input_buf_siz)
+		return -1;
+
+	return input_buf[input_buf_ptr++];
+}
+
+static int __peek_char(void)
+{
+	if (input_buf_ptr >= input_buf_siz)
+		return -1;
+
+	return input_buf[input_buf_ptr];
+}
+
+/**
+ * pevent_peek_char - peek at the next character that will be read
+ *
+ * Returns the next character read, or -1 if end of buffer.
+ */
+int pevent_peek_char(void)
+{
+	return __peek_char();
+}
+
+static int extend_token(char **tok, char *buf, int size)
+{
+	char *newtok = realloc(*tok, size);
+
+	if (!newtok) {
+		free(*tok);
+		*tok = NULL;
+		return -1;
+	}
+
+	if (!*tok)
+		strcpy(newtok, buf);
+	else
+		strcat(newtok, buf);
+	*tok = newtok;
+
+	return 0;
+}
+
+static enum event_type force_token(const char *str, char **tok);
+
+static enum event_type __read_token(char **tok)
+{
+	char buf[BUFSIZ];
+	int ch, last_ch, quote_ch, next_ch;
+	int i = 0;
+	int tok_size = 0;
+	enum event_type type;
+
+	*tok = NULL;
+
+
+	ch = __read_char();
+	if (ch < 0)
+		return EVENT_NONE;
+
+	type = get_type(ch);
+	if (type == EVENT_NONE)
+		return type;
+
+	buf[i++] = ch;
+
+	switch (type) {
+	case EVENT_NEWLINE:
+	case EVENT_DELIM:
+		if (asprintf(tok, "%c", ch) < 0)
+			return EVENT_ERROR;
+
+		return type;
+
+	case EVENT_OP:
+		switch (ch) {
+		case '-':
+			next_ch = __peek_char();
+			if (next_ch == '>') {
+				buf[i++] = __read_char();
+				break;
+			}
+			/* fall through */
+		case '+':
+		case '|':
+		case '&':
+		case '>':
+		case '<':
+			last_ch = ch;
+			ch = __peek_char();
+			if (ch != last_ch)
+				goto test_equal;
+			buf[i++] = __read_char();
+			switch (last_ch) {
+			case '>':
+			case '<':
+				goto test_equal;
+			default:
+				break;
+			}
+			break;
+		case '!':
+		case '=':
+			goto test_equal;
+		default: /* what should we do instead? */
+			break;
+		}
+		buf[i] = 0;
+		*tok = strdup(buf);
+		return type;
+
+ test_equal:
+		ch = __peek_char();
+		if (ch == '=')
+			buf[i++] = __read_char();
+		goto out;
+
+	case EVENT_DQUOTE:
+	case EVENT_SQUOTE:
+		/* don't keep quotes */
+		i--;
+		quote_ch = ch;
+		last_ch = 0;
+ concat:
+		do {
+			if (i == (BUFSIZ - 1)) {
+				buf[i] = 0;
+				tok_size += BUFSIZ;
+
+				if (extend_token(tok, buf, tok_size) < 0)
+					return EVENT_NONE;
+				i = 0;
+			}
+			last_ch = ch;
+			ch = __read_char();
+			buf[i++] = ch;
+			/* the '\' '\' will cancel itself */
+			if (ch == '\\' && last_ch == '\\')
+				last_ch = 0;
+		} while (ch != quote_ch || last_ch == '\\');
+		/* remove the last quote */
+		i--;
+
+		/*
+		 * For strings (double quotes) check the next token.
+		 * If it is another string, concatinate the two.
+		 */
+		if (type == EVENT_DQUOTE) {
+			unsigned long long save_input_buf_ptr = input_buf_ptr;
+
+			do {
+				ch = __read_char();
+			} while (isspace(ch));
+			if (ch == '"')
+				goto concat;
+			input_buf_ptr = save_input_buf_ptr;
+		}
+
+		goto out;
+
+	case EVENT_ERROR ... EVENT_SPACE:
+	case EVENT_ITEM:
+	default:
+		break;
+	}
+
+	while (get_type(__peek_char()) == type) {
+		if (i == (BUFSIZ - 1)) {
+			buf[i] = 0;
+			tok_size += BUFSIZ;
+
+			if (extend_token(tok, buf, tok_size) < 0)
+				return EVENT_NONE;
+			i = 0;
+		}
+		ch = __read_char();
+		buf[i++] = ch;
+	}
+
+ out:
+	buf[i] = 0;
+	if (extend_token(tok, buf, tok_size + i + 1) < 0)
+		return EVENT_NONE;
+
+	if (type == EVENT_ITEM) {
+		/*
+		 * Older versions of the kernel has a bug that
+		 * creates invalid symbols and will break the mac80211
+		 * parsing. This is a work around to that bug.
+		 *
+		 * See Linux kernel commit:
+		 *  811cb50baf63461ce0bdb234927046131fc7fa8b
+		 */
+		if (strcmp(*tok, "LOCAL_PR_FMT") == 0) {
+			free(*tok);
+			*tok = NULL;
+			return force_token("\"\%s\" ", tok);
+		} else if (strcmp(*tok, "STA_PR_FMT") == 0) {
+			free(*tok);
+			*tok = NULL;
+			return force_token("\" sta:%pM\" ", tok);
+		} else if (strcmp(*tok, "VIF_PR_FMT") == 0) {
+			free(*tok);
+			*tok = NULL;
+			return force_token("\" vif:%p(%d)\" ", tok);
+		}
+	}
+
+	return type;
+}
+
+static enum event_type force_token(const char *str, char **tok)
+{
+	const char *save_input_buf;
+	unsigned long long save_input_buf_ptr;
+	unsigned long long save_input_buf_siz;
+	enum event_type type;
+	
+	/* save off the current input pointers */
+	save_input_buf = input_buf;
+	save_input_buf_ptr = input_buf_ptr;
+	save_input_buf_siz = input_buf_siz;
+
+	init_input_buf(str, strlen(str));
+
+	type = __read_token(tok);
+
+	/* reset back to original token */
+	input_buf = save_input_buf;
+	input_buf_ptr = save_input_buf_ptr;
+	input_buf_siz = save_input_buf_siz;
+
+	return type;
+}
+
+static void free_token(char *tok)
+{
+	if (tok)
+		free(tok);
+}
+
+static enum event_type read_token(char **tok)
+{
+	enum event_type type;
+
+	for (;;) {
+		type = __read_token(tok);
+		if (type != EVENT_SPACE)
+			return type;
+
+		free_token(*tok);
+	}
+
+	/* not reached */
+	*tok = NULL;
+	return EVENT_NONE;
+}
+
+/**
+ * pevent_read_token - access to utilites to use the pevent parser
+ * @tok: The token to return
+ *
+ * This will parse tokens from the string given by
+ * pevent_init_data().
+ *
+ * Returns the token type.
+ */
+enum event_type pevent_read_token(char **tok)
+{
+	return read_token(tok);
+}
+
+/**
+ * pevent_free_token - free a token returned by pevent_read_token
+ * @token: the token to free
+ */
+void pevent_free_token(char *token)
+{
+	free_token(token);
+}
+
+/* no newline */
+static enum event_type read_token_item(char **tok)
+{
+	enum event_type type;
+
+	for (;;) {
+		type = __read_token(tok);
+		if (type != EVENT_SPACE && type != EVENT_NEWLINE)
+			return type;
+		free_token(*tok);
+		*tok = NULL;
+	}
+
+	/* not reached */
+	*tok = NULL;
+	return EVENT_NONE;
+}
+
+static int test_type(enum event_type type, enum event_type expect)
+{
+	if (type != expect) {
+		do_warning("Error: expected type %d but read %d",
+		    expect, type);
+		return -1;
+	}
+	return 0;
+}
+
+static int test_type_token(enum event_type type, const char *token,
+		    enum event_type expect, const char *expect_tok)
+{
+	if (type != expect) {
+		do_warning("Error: expected type %d but read %d",
+		    expect, type);
+		return -1;
+	}
+
+	if (strcmp(token, expect_tok) != 0) {
+		do_warning("Error: expected '%s' but read '%s'",
+		    expect_tok, token);
+		return -1;
+	}
+	return 0;
+}
+
+static int __read_expect_type(enum event_type expect, char **tok, int newline_ok)
+{
+	enum event_type type;
+
+	if (newline_ok)
+		type = read_token(tok);
+	else
+		type = read_token_item(tok);
+	return test_type(type, expect);
+}
+
+static int read_expect_type(enum event_type expect, char **tok)
+{
+	return __read_expect_type(expect, tok, 1);
+}
+
+static int __read_expected(enum event_type expect, const char *str,
+			   int newline_ok)
+{
+	enum event_type type;
+	char *token;
+	int ret;
+
+	if (newline_ok)
+		type = read_token(&token);
+	else
+		type = read_token_item(&token);
+
+	ret = test_type_token(type, token, expect, str);
+
+	free_token(token);
+
+	return ret;
+}
+
+static int read_expected(enum event_type expect, const char *str)
+{
+	return __read_expected(expect, str, 1);
+}
+
+static int read_expected_item(enum event_type expect, const char *str)
+{
+	return __read_expected(expect, str, 0);
+}
+
+static char *event_read_name(void)
+{
+	char *token;
+
+	if (read_expected(EVENT_ITEM, "name") < 0)
+		return NULL;
+
+	if (read_expected(EVENT_OP, ":") < 0)
+		return NULL;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+
+	return token;
+
+ fail:
+	free_token(token);
+	return NULL;
+}
+
+static int event_read_id(void)
+{
+	char *token;
+	int id;
+
+	if (read_expected_item(EVENT_ITEM, "ID") < 0)
+		return -1;
+
+	if (read_expected(EVENT_OP, ":") < 0)
+		return -1;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+
+	id = strtoul(token, NULL, 0);
+	free_token(token);
+	return id;
+
+ fail:
+	free_token(token);
+	return -1;
+}
+
+static int field_is_string(struct format_field *field)
+{
+	if ((field->flags & FIELD_IS_ARRAY) &&
+	    (strstr(field->type, "char") || strstr(field->type, "u8") ||
+	     strstr(field->type, "s8")))
+		return 1;
+
+	return 0;
+}
+
+static int field_is_dynamic(struct format_field *field)
+{
+	if (strncmp(field->type, "__data_loc", 10) == 0)
+		return 1;
+
+	return 0;
+}
+
+static int field_is_long(struct format_field *field)
+{
+	/* includes long long */
+	if (strstr(field->type, "long"))
+		return 1;
+
+	return 0;
+}
+
+static unsigned int type_size(const char *name)
+{
+	/* This covers all FIELD_IS_STRING types. */
+	static struct {
+		const char *type;
+		unsigned int size;
+	} table[] = {
+		{ "u8",   1 },
+		{ "u16",  2 },
+		{ "u32",  4 },
+		{ "u64",  8 },
+		{ "s8",   1 },
+		{ "s16",  2 },
+		{ "s32",  4 },
+		{ "s64",  8 },
+		{ "char", 1 },
+		{ },
+	};
+	int i;
+
+	for (i = 0; table[i].type; i++) {
+		if (!strcmp(table[i].type, name))
+			return table[i].size;
+	}
+
+	return 0;
+}
+
+static int event_read_fields(struct event_format *event, struct format_field **fields)
+{
+	struct format_field *field = NULL;
+	enum event_type type;
+	char *token;
+	char *last_token;
+	int count = 0;
+
+	do {
+		unsigned int size_dynamic = 0;
+
+		type = read_token(&token);
+		if (type == EVENT_NEWLINE) {
+			free_token(token);
+			return count;
+		}
+
+		count++;
+
+		if (test_type_token(type, token, EVENT_ITEM, "field"))
+			goto fail;
+		free_token(token);
+
+		type = read_token(&token);
+		/*
+		 * The ftrace fields may still use the "special" name.
+		 * Just ignore it.
+		 */
+		if (event->flags & EVENT_FL_ISFTRACE &&
+		    type == EVENT_ITEM && strcmp(token, "special") == 0) {
+			free_token(token);
+			type = read_token(&token);
+		}
+
+		if (test_type_token(type, token, EVENT_OP, ":") < 0)
+			goto fail;
+
+		free_token(token);
+		if (read_expect_type(EVENT_ITEM, &token) < 0)
+			goto fail;
+
+		last_token = token;
+
+		field = calloc(1, sizeof(*field));
+		if (!field)
+			goto fail;
+
+		field->event = event;
+
+		/* read the rest of the type */
+		for (;;) {
+			type = read_token(&token);
+			if (type == EVENT_ITEM ||
+			    (type == EVENT_OP && strcmp(token, "*") == 0) ||
+			    /*
+			     * Some of the ftrace fields are broken and have
+			     * an illegal "." in them.
+			     */
+			    (event->flags & EVENT_FL_ISFTRACE &&
+			     type == EVENT_OP && strcmp(token, ".") == 0)) {
+
+				if (strcmp(token, "*") == 0)
+					field->flags |= FIELD_IS_POINTER;
+
+				if (field->type) {
+					char *new_type;
+					new_type = realloc(field->type,
+							   strlen(field->type) +
+							   strlen(last_token) + 2);
+					if (!new_type) {
+						free(last_token);
+						goto fail;
+					}
+					field->type = new_type;
+					strcat(field->type, " ");
+					strcat(field->type, last_token);
+					free(last_token);
+				} else
+					field->type = last_token;
+				last_token = token;
+				continue;
+			}
+
+			break;
+		}
+
+		if (!field->type) {
+			do_warning_event(event, "%s: no type found", __func__);
+			goto fail;
+		}
+		field->name = last_token;
+
+		if (test_type(type, EVENT_OP))
+			goto fail;
+
+		if (strcmp(token, "[") == 0) {
+			enum event_type last_type = type;
+			char *brackets = token;
+			char *new_brackets;
+			int len;
+
+			field->flags |= FIELD_IS_ARRAY;
+
+			type = read_token(&token);
+
+			if (type == EVENT_ITEM)
+				field->arraylen = strtoul(token, NULL, 0);
+			else
+				field->arraylen = 0;
+
+		        while (strcmp(token, "]") != 0) {
+				if (last_type == EVENT_ITEM &&
+				    type == EVENT_ITEM)
+					len = 2;
+				else
+					len = 1;
+				last_type = type;
+
+				new_brackets = realloc(brackets,
+						       strlen(brackets) +
+						       strlen(token) + len);
+				if (!new_brackets) {
+					free(brackets);
+					goto fail;
+				}
+				brackets = new_brackets;
+				if (len == 2)
+					strcat(brackets, " ");
+				strcat(brackets, token);
+				/* We only care about the last token */
+				field->arraylen = strtoul(token, NULL, 0);
+				free_token(token);
+				type = read_token(&token);
+				if (type == EVENT_NONE) {
+					do_warning_event(event, "failed to find token");
+					goto fail;
+				}
+			}
+
+			free_token(token);
+
+			new_brackets = realloc(brackets, strlen(brackets) + 2);
+			if (!new_brackets) {
+				free(brackets);
+				goto fail;
+			}
+			brackets = new_brackets;
+			strcat(brackets, "]");
+
+			/* add brackets to type */
+
+			type = read_token(&token);
+			/*
+			 * If the next token is not an OP, then it is of
+			 * the format: type [] item;
+			 */
+			if (type == EVENT_ITEM) {
+				char *new_type;
+				new_type = realloc(field->type,
+						   strlen(field->type) +
+						   strlen(field->name) +
+						   strlen(brackets) + 2);
+				if (!new_type) {
+					free(brackets);
+					goto fail;
+				}
+				field->type = new_type;
+				strcat(field->type, " ");
+				strcat(field->type, field->name);
+				size_dynamic = type_size(field->name);
+				free_token(field->name);
+				strcat(field->type, brackets);
+				field->name = token;
+				type = read_token(&token);
+			} else {
+				char *new_type;
+				new_type = realloc(field->type,
+						   strlen(field->type) +
+						   strlen(brackets) + 1);
+				if (!new_type) {
+					free(brackets);
+					goto fail;
+				}
+				field->type = new_type;
+				strcat(field->type, brackets);
+			}
+			free(brackets);
+		}
+
+		if (field_is_string(field))
+			field->flags |= FIELD_IS_STRING;
+		if (field_is_dynamic(field))
+			field->flags |= FIELD_IS_DYNAMIC;
+		if (field_is_long(field))
+			field->flags |= FIELD_IS_LONG;
+
+		if (test_type_token(type, token,  EVENT_OP, ";"))
+			goto fail;
+		free_token(token);
+
+		if (read_expected(EVENT_ITEM, "offset") < 0)
+			goto fail_expect;
+
+		if (read_expected(EVENT_OP, ":") < 0)
+			goto fail_expect;
+
+		if (read_expect_type(EVENT_ITEM, &token))
+			goto fail;
+		field->offset = strtoul(token, NULL, 0);
+		free_token(token);
+
+		if (read_expected(EVENT_OP, ";") < 0)
+			goto fail_expect;
+
+		if (read_expected(EVENT_ITEM, "size") < 0)
+			goto fail_expect;
+
+		if (read_expected(EVENT_OP, ":") < 0)
+			goto fail_expect;
+
+		if (read_expect_type(EVENT_ITEM, &token))
+			goto fail;
+		field->size = strtoul(token, NULL, 0);
+		free_token(token);
+
+		if (read_expected(EVENT_OP, ";") < 0)
+			goto fail_expect;
+
+		type = read_token(&token);
+		if (type != EVENT_NEWLINE) {
+			/* newer versions of the kernel have a "signed" type */
+			if (test_type_token(type, token, EVENT_ITEM, "signed"))
+				goto fail;
+
+			free_token(token);
+
+			if (read_expected(EVENT_OP, ":") < 0)
+				goto fail_expect;
+
+			if (read_expect_type(EVENT_ITEM, &token))
+				goto fail;
+
+			if (strtoul(token, NULL, 0))
+				field->flags |= FIELD_IS_SIGNED;
+
+			free_token(token);
+			if (read_expected(EVENT_OP, ";") < 0)
+				goto fail_expect;
+
+			if (read_expect_type(EVENT_NEWLINE, &token))
+				goto fail;
+		}
+
+		free_token(token);
+
+		if (field->flags & FIELD_IS_ARRAY) {
+			if (field->arraylen)
+				field->elementsize = field->size / field->arraylen;
+			else if (field->flags & FIELD_IS_DYNAMIC)
+				field->elementsize = size_dynamic;
+			else if (field->flags & FIELD_IS_STRING)
+				field->elementsize = 1;
+			else if (field->flags & FIELD_IS_LONG)
+				field->elementsize = event->pevent ?
+						     event->pevent->long_size :
+						     sizeof(long);
+		} else
+			field->elementsize = field->size;
+
+		*fields = field;
+		fields = &field->next;
+
+	} while (1);
+
+	return 0;
+
+fail:
+	free_token(token);
+fail_expect:
+	if (field) {
+		free(field->type);
+		free(field->name);
+		free(field);
+	}
+	return -1;
+}
+
+static int event_read_format(struct event_format *event)
+{
+	char *token;
+	int ret;
+
+	if (read_expected_item(EVENT_ITEM, "format") < 0)
+		return -1;
+
+	if (read_expected(EVENT_OP, ":") < 0)
+		return -1;
+
+	if (read_expect_type(EVENT_NEWLINE, &token))
+		goto fail;
+	free_token(token);
+
+	ret = event_read_fields(event, &event->format.common_fields);
+	if (ret < 0)
+		return ret;
+	event->format.nr_common = ret;
+
+	ret = event_read_fields(event, &event->format.fields);
+	if (ret < 0)
+		return ret;
+	event->format.nr_fields = ret;
+
+	return 0;
+
+ fail:
+	free_token(token);
+	return -1;
+}
+
+static enum event_type
+process_arg_token(struct event_format *event, struct print_arg *arg,
+		  char **tok, enum event_type type);
+
+static enum event_type
+process_arg(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	enum event_type type;
+	char *token;
+
+	type = read_token(&token);
+	*tok = token;
+
+	return process_arg_token(event, arg, tok, type);
+}
+
+static enum event_type
+process_op(struct event_format *event, struct print_arg *arg, char **tok);
+
+/*
+ * For __print_symbolic() and __print_flags, we need to completely
+ * evaluate the first argument, which defines what to print next.
+ */
+static enum event_type
+process_field_arg(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	enum event_type type;
+
+	type = process_arg(event, arg, tok);
+
+	while (type == EVENT_OP) {
+		type = process_op(event, arg, tok);
+	}
+
+	return type;
+}
+
+static enum event_type
+process_cond(struct event_format *event, struct print_arg *top, char **tok)
+{
+	struct print_arg *arg, *left, *right;
+	enum event_type type;
+	char *token = NULL;
+
+	arg = alloc_arg();
+	left = alloc_arg();
+	right = alloc_arg();
+
+	if (!arg || !left || !right) {
+		do_warning_event(event, "%s: not enough memory!", __func__);
+		/* arg will be freed at out_free */
+		free_arg(left);
+		free_arg(right);
+		goto out_free;
+	}
+
+	arg->type = PRINT_OP;
+	arg->op.left = left;
+	arg->op.right = right;
+
+	*tok = NULL;
+	type = process_arg(event, left, &token);
+
+ again:
+	/* Handle other operations in the arguments */
+	if (type == EVENT_OP && strcmp(token, ":") != 0) {
+		type = process_op(event, left, &token);
+		goto again;
+	}
+
+	if (test_type_token(type, token, EVENT_OP, ":"))
+		goto out_free;
+
+	arg->op.op = token;
+
+	type = process_arg(event, right, &token);
+
+	top->op.right = arg;
+
+	*tok = token;
+	return type;
+
+out_free:
+	/* Top may point to itself */
+	top->op.right = NULL;
+	free_token(token);
+	free_arg(arg);
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_array(struct event_format *event, struct print_arg *top, char **tok)
+{
+	struct print_arg *arg;
+	enum event_type type;
+	char *token = NULL;
+
+	arg = alloc_arg();
+	if (!arg) {
+		do_warning_event(event, "%s: not enough memory!", __func__);
+		/* '*tok' is set to top->op.op.  No need to free. */
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
+	*tok = NULL;
+	type = process_arg(event, arg, &token);
+	if (test_type_token(type, token, EVENT_OP, "]"))
+		goto out_free;
+
+	top->op.right = arg;
+
+	free_token(token);
+	type = read_token_item(&token);
+	*tok = token;
+
+	return type;
+
+out_free:
+	free_token(token);
+	free_arg(arg);
+	return EVENT_ERROR;
+}
+
+static int get_op_prio(char *op)
+{
+	if (!op[1]) {
+		switch (op[0]) {
+		case '~':
+		case '!':
+			return 4;
+		case '*':
+		case '/':
+		case '%':
+			return 6;
+		case '+':
+		case '-':
+			return 7;
+			/* '>>' and '<<' are 8 */
+		case '<':
+		case '>':
+			return 9;
+			/* '==' and '!=' are 10 */
+		case '&':
+			return 11;
+		case '^':
+			return 12;
+		case '|':
+			return 13;
+		case '?':
+			return 16;
+		default:
+			do_warning("unknown op '%c'", op[0]);
+			return -1;
+		}
+	} else {
+		if (strcmp(op, "++") == 0 ||
+		    strcmp(op, "--") == 0) {
+			return 3;
+		} else if (strcmp(op, ">>") == 0 ||
+			   strcmp(op, "<<") == 0) {
+			return 8;
+		} else if (strcmp(op, ">=") == 0 ||
+			   strcmp(op, "<=") == 0) {
+			return 9;
+		} else if (strcmp(op, "==") == 0 ||
+			   strcmp(op, "!=") == 0) {
+			return 10;
+		} else if (strcmp(op, "&&") == 0) {
+			return 14;
+		} else if (strcmp(op, "||") == 0) {
+			return 15;
+		} else {
+			do_warning("unknown op '%s'", op);
+			return -1;
+		}
+	}
+}
+
+static int set_op_prio(struct print_arg *arg)
+{
+
+	/* single ops are the greatest */
+	if (!arg->op.left || arg->op.left->type == PRINT_NULL)
+		arg->op.prio = 0;
+	else
+		arg->op.prio = get_op_prio(arg->op.op);
+
+	return arg->op.prio;
+}
+
+/* Note, *tok does not get freed, but will most likely be saved */
+static enum event_type
+process_op(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	struct print_arg *left, *right = NULL;
+	enum event_type type;
+	char *token;
+
+	/* the op is passed in via tok */
+	token = *tok;
+
+	if (arg->type == PRINT_OP && !arg->op.left) {
+		/* handle single op */
+		if (token[1]) {
+			do_warning_event(event, "bad op token %s", token);
+			goto out_free;
+		}
+		switch (token[0]) {
+		case '~':
+		case '!':
+		case '+':
+		case '-':
+			break;
+		default:
+			do_warning_event(event, "bad op token %s", token);
+			goto out_free;
+
+		}
+
+		/* make an empty left */
+		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
+		left->type = PRINT_NULL;
+		arg->op.left = left;
+
+		right = alloc_arg();
+		if (!right)
+			goto out_warn_free;
+
+		arg->op.right = right;
+
+		/* do not free the token, it belongs to an op */
+		*tok = NULL;
+		type = process_arg(event, right, tok);
+
+	} else if (strcmp(token, "?") == 0) {
+
+		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
+		/* copy the top arg to the left */
+		*left = *arg;
+
+		arg->type = PRINT_OP;
+		arg->op.op = token;
+		arg->op.left = left;
+		arg->op.prio = 0;
+
+		/* it will set arg->op.right */
+		type = process_cond(event, arg, tok);
+
+	} else if (strcmp(token, ">>") == 0 ||
+		   strcmp(token, "<<") == 0 ||
+		   strcmp(token, "&") == 0 ||
+		   strcmp(token, "|") == 0 ||
+		   strcmp(token, "&&") == 0 ||
+		   strcmp(token, "||") == 0 ||
+		   strcmp(token, "-") == 0 ||
+		   strcmp(token, "+") == 0 ||
+		   strcmp(token, "*") == 0 ||
+		   strcmp(token, "^") == 0 ||
+		   strcmp(token, "/") == 0 ||
+		   strcmp(token, "<") == 0 ||
+		   strcmp(token, ">") == 0 ||
+		   strcmp(token, "<=") == 0 ||
+		   strcmp(token, ">=") == 0 ||
+		   strcmp(token, "==") == 0 ||
+		   strcmp(token, "!=") == 0) {
+
+		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
+		/* copy the top arg to the left */
+		*left = *arg;
+
+		arg->type = PRINT_OP;
+		arg->op.op = token;
+		arg->op.left = left;
+		arg->op.right = NULL;
+
+		if (set_op_prio(arg) == -1) {
+			event->flags |= EVENT_FL_FAILED;
+			/* arg->op.op (= token) will be freed at out_free */
+			arg->op.op = NULL;
+			goto out_free;
+		}
+
+		type = read_token_item(&token);
+		*tok = token;
+
+		/* could just be a type pointer */
+		if ((strcmp(arg->op.op, "*") == 0) &&
+		    type == EVENT_DELIM && (strcmp(token, ")") == 0)) {
+			char *new_atom;
+
+			if (left->type != PRINT_ATOM) {
+				do_warning_event(event, "bad pointer type");
+				goto out_free;
+			}
+			new_atom = realloc(left->atom.atom,
+					    strlen(left->atom.atom) + 3);
+			if (!new_atom)
+				goto out_warn_free;
+
+			left->atom.atom = new_atom;
+			strcat(left->atom.atom, " *");
+			free(arg->op.op);
+			*arg = *left;
+			free(left);
+
+			return type;
+		}
+
+		right = alloc_arg();
+		if (!right)
+			goto out_warn_free;
+
+		type = process_arg_token(event, right, tok, type);
+
+		if (right->type == PRINT_OP &&
+		    get_op_prio(arg->op.op) < get_op_prio(right->op.op)) {
+			struct print_arg tmp;
+
+			/* rotate ops according to the priority */
+			arg->op.right = right->op.left;
+
+			tmp = *arg;
+			*arg = *right;
+			*right = tmp;
+
+			arg->op.left = right;
+		} else {
+			arg->op.right = right;
+		}
+
+	} else if (strcmp(token, "[") == 0) {
+
+		left = alloc_arg();
+		if (!left)
+			goto out_warn_free;
+
+		*left = *arg;
+
+		arg->type = PRINT_OP;
+		arg->op.op = token;
+		arg->op.left = left;
+
+		arg->op.prio = 0;
+
+		/* it will set arg->op.right */
+		type = process_array(event, arg, tok);
+
+	} else {
+		do_warning_event(event, "unknown op '%s'", token);
+		event->flags |= EVENT_FL_FAILED;
+		/* the arg is now the left side */
+		goto out_free;
+	}
+
+	if (type == EVENT_OP && strcmp(*tok, ":") != 0) {
+		int prio;
+
+		/* higher prios need to be closer to the root */
+		prio = get_op_prio(*tok);
+
+		if (prio > arg->op.prio)
+			return process_op(event, arg, tok);
+
+		return process_op(event, right, tok);
+	}
+
+	return type;
+
+out_warn_free:
+	do_warning_event(event, "%s: not enough memory!", __func__);
+out_free:
+	free_token(token);
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_entry(struct event_format *event __maybe_unused, struct print_arg *arg,
+	      char **tok)
+{
+	enum event_type type;
+	char *field;
+	char *token;
+
+	if (read_expected(EVENT_OP, "->") < 0)
+		goto out_err;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto out_free;
+	field = token;
+
+	arg->type = PRINT_FIELD;
+	arg->field.name = field;
+
+	if (is_flag_field) {
+		arg->field.field = pevent_find_any_field(event, arg->field.name);
+		arg->field.field->flags |= FIELD_IS_FLAG;
+		is_flag_field = 0;
+	} else if (is_symbolic_field) {
+		arg->field.field = pevent_find_any_field(event, arg->field.name);
+		arg->field.field->flags |= FIELD_IS_SYMBOLIC;
+		is_symbolic_field = 0;
+	}
+
+	type = read_token(&token);
+	*tok = token;
+
+	return type;
+
+ out_free:
+	free_token(token);
+ out_err:
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static int alloc_and_process_delim(struct event_format *event, char *next_token,
+				   struct print_arg **print_arg)
+{
+	struct print_arg *field;
+	enum event_type type;
+	char *token;
+	int ret = 0;
+
+	field = alloc_arg();
+	if (!field) {
+		do_warning_event(event, "%s: not enough memory!", __func__);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	type = process_arg(event, field, &token);
+
+	if (test_type_token(type, token, EVENT_DELIM, next_token)) {
+		errno = EINVAL;
+		ret = -1;
+		free_arg(field);
+		goto out_free_token;
+	}
+
+	*print_arg = field;
+
+out_free_token:
+	free_token(token);
+
+	return ret;
+}
+
+static char *arg_eval (struct print_arg *arg);
+
+static unsigned long long
+eval_type_str(unsigned long long val, const char *type, int pointer)
+{
+	int sign = 0;
+	char *ref;
+	int len;
+
+	len = strlen(type);
+
+	if (pointer) {
+
+		if (type[len-1] != '*') {
+			do_warning("pointer expected with non pointer type");
+			return val;
+		}
+
+		ref = malloc(len);
+		if (!ref) {
+			do_warning("%s: not enough memory!", __func__);
+			return val;
+		}
+		memcpy(ref, type, len);
+
+		/* chop off the " *" */
+		ref[len - 2] = 0;
+
+		val = eval_type_str(val, ref, 0);
+		free(ref);
+		return val;
+	}
+
+	/* check if this is a pointer */
+	if (type[len - 1] == '*')
+		return val;
+
+	/* Try to figure out the arg size*/
+	if (strncmp(type, "struct", 6) == 0)
+		/* all bets off */
+		return val;
+
+	if (strcmp(type, "u8") == 0)
+		return val & 0xff;
+
+	if (strcmp(type, "u16") == 0)
+		return val & 0xffff;
+
+	if (strcmp(type, "u32") == 0)
+		return val & 0xffffffff;
+
+	if (strcmp(type, "u64") == 0 ||
+	    strcmp(type, "s64"))
+		return val;
+
+	if (strcmp(type, "s8") == 0)
+		return (unsigned long long)(char)val & 0xff;
+
+	if (strcmp(type, "s16") == 0)
+		return (unsigned long long)(short)val & 0xffff;
+
+	if (strcmp(type, "s32") == 0)
+		return (unsigned long long)(int)val & 0xffffffff;
+
+	if (strncmp(type, "unsigned ", 9) == 0) {
+		sign = 0;
+		type += 9;
+	}
+
+	if (strcmp(type, "char") == 0) {
+		if (sign)
+			return (unsigned long long)(char)val & 0xff;
+		else
+			return val & 0xff;
+	}
+
+	if (strcmp(type, "short") == 0) {
+		if (sign)
+			return (unsigned long long)(short)val & 0xffff;
+		else
+			return val & 0xffff;
+	}
+
+	if (strcmp(type, "int") == 0) {
+		if (sign)
+			return (unsigned long long)(int)val & 0xffffffff;
+		else
+			return val & 0xffffffff;
+	}
+
+	return val;
+}
+
+/*
+ * Try to figure out the type.
+ */
+static unsigned long long
+eval_type(unsigned long long val, struct print_arg *arg, int pointer)
+{
+	if (arg->type != PRINT_TYPE) {
+		do_warning("expected type argument");
+		return 0;
+	}
+
+	return eval_type_str(val, arg->typecast.type, pointer);
+}
+
+static int arg_num_eval(struct print_arg *arg, long long *val)
+{
+	long long left, right;
+	int ret = 1;
+
+	switch (arg->type) {
+	case PRINT_ATOM:
+		*val = strtoll(arg->atom.atom, NULL, 0);
+		break;
+	case PRINT_TYPE:
+		ret = arg_num_eval(arg->typecast.item, val);
+		if (!ret)
+			break;
+		*val = eval_type(*val, arg, 0);
+		break;
+	case PRINT_OP:
+		switch (arg->op.op[0]) {
+		case '|':
+			ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+			if (arg->op.op[1])
+				*val = left || right;
+			else
+				*val = left | right;
+			break;
+		case '&':
+			ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+			if (arg->op.op[1])
+				*val = left && right;
+			else
+				*val = left & right;
+			break;
+		case '<':
+			ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+			switch (arg->op.op[1]) {
+			case 0:
+				*val = left < right;
+				break;
+			case '<':
+				*val = left << right;
+				break;
+			case '=':
+				*val = left <= right;
+				break;
+			default:
+				do_warning("unknown op '%s'", arg->op.op);
+				ret = 0;
+			}
+			break;
+		case '>':
+			ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+			switch (arg->op.op[1]) {
+			case 0:
+				*val = left > right;
+				break;
+			case '>':
+				*val = left >> right;
+				break;
+			case '=':
+				*val = left >= right;
+				break;
+			default:
+				do_warning("unknown op '%s'", arg->op.op);
+				ret = 0;
+			}
+			break;
+		case '=':
+			ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+
+			if (arg->op.op[1] != '=') {
+				do_warning("unknown op '%s'", arg->op.op);
+				ret = 0;
+			} else
+				*val = left == right;
+			break;
+		case '!':
+			ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+
+			switch (arg->op.op[1]) {
+			case '=':
+				*val = left != right;
+				break;
+			default:
+				do_warning("unknown op '%s'", arg->op.op);
+				ret = 0;
+			}
+			break;
+		case '-':
+			/* check for negative */
+			if (arg->op.left->type == PRINT_NULL)
+				left = 0;
+			else
+				ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+			*val = left - right;
+			break;
+		case '+':
+			if (arg->op.left->type == PRINT_NULL)
+				left = 0;
+			else
+				ret = arg_num_eval(arg->op.left, &left);
+			if (!ret)
+				break;
+			ret = arg_num_eval(arg->op.right, &right);
+			if (!ret)
+				break;
+			*val = left + right;
+			break;
+		default:
+			do_warning("unknown op '%s'", arg->op.op);
+			ret = 0;
+		}
+		break;
+
+	case PRINT_NULL:
+	case PRINT_FIELD ... PRINT_SYMBOL:
+	case PRINT_STRING:
+	case PRINT_BSTRING:
+	case PRINT_BITMASK:
+	default:
+		do_warning("invalid eval type %d", arg->type);
+		ret = 0;
+
+	}
+	return ret;
+}
+
+static char *arg_eval (struct print_arg *arg)
+{
+	long long val;
+	static char buf[20];
+
+	switch (arg->type) {
+	case PRINT_ATOM:
+		return arg->atom.atom;
+	case PRINT_TYPE:
+		return arg_eval(arg->typecast.item);
+	case PRINT_OP:
+		if (!arg_num_eval(arg, &val))
+			break;
+		sprintf(buf, "%lld", val);
+		return buf;
+
+	case PRINT_NULL:
+	case PRINT_FIELD ... PRINT_SYMBOL:
+	case PRINT_STRING:
+	case PRINT_BSTRING:
+	case PRINT_BITMASK:
+	default:
+		do_warning("invalid eval type %d", arg->type);
+		break;
+	}
+
+	return NULL;
+}
+
+static enum event_type
+process_fields(struct event_format *event, struct print_flag_sym **list, char **tok)
+{
+	enum event_type type;
+	struct print_arg *arg = NULL;
+	struct print_flag_sym *field;
+	char *token = *tok;
+	char *value;
+
+	do {
+		free_token(token);
+		type = read_token_item(&token);
+		if (test_type_token(type, token, EVENT_OP, "{"))
+			break;
+
+		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
+
+		free_token(token);
+		type = process_arg(event, arg, &token);
+
+		if (type == EVENT_OP)
+			type = process_op(event, arg, &token);
+
+		if (type == EVENT_ERROR)
+			goto out_free;
+
+		if (test_type_token(type, token, EVENT_DELIM, ","))
+			goto out_free;
+
+		field = calloc(1, sizeof(*field));
+		if (!field)
+			goto out_free;
+
+		value = arg_eval(arg);
+		if (value == NULL)
+			goto out_free_field;
+		field->value = strdup(value);
+		if (field->value == NULL)
+			goto out_free_field;
+
+		free_arg(arg);
+		arg = alloc_arg();
+		if (!arg)
+			goto out_free;
+
+		free_token(token);
+		type = process_arg(event, arg, &token);
+		if (test_type_token(type, token, EVENT_OP, "}"))
+			goto out_free_field;
+
+		value = arg_eval(arg);
+		if (value == NULL)
+			goto out_free_field;
+		field->str = strdup(value);
+		if (field->str == NULL)
+			goto out_free_field;
+		free_arg(arg);
+		arg = NULL;
+
+		*list = field;
+		list = &field->next;
+
+		free_token(token);
+		type = read_token_item(&token);
+	} while (type == EVENT_DELIM && strcmp(token, ",") == 0);
+
+	*tok = token;
+	return type;
+
+out_free_field:
+	free_flag_sym(field);
+out_free:
+	free_arg(arg);
+	free_token(token);
+	*tok = NULL;
+
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_flags(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	struct print_arg *field;
+	enum event_type type;
+	char *token = NULL;
+
+	memset(arg, 0, sizeof(*arg));
+	arg->type = PRINT_FLAGS;
+
+	field = alloc_arg();
+	if (!field) {
+		do_warning_event(event, "%s: not enough memory!", __func__);
+		goto out_free;
+	}
+
+	type = process_field_arg(event, field, &token);
+
+	/* Handle operations in the first argument */
+	while (type == EVENT_OP)
+		type = process_op(event, field, &token);
+
+	if (test_type_token(type, token, EVENT_DELIM, ","))
+		goto out_free_field;
+	free_token(token);
+
+	arg->flags.field = field;
+
+	type = read_token_item(&token);
+	if (event_item_type(type)) {
+		arg->flags.delim = token;
+		type = read_token_item(&token);
+	}
+
+	if (test_type_token(type, token, EVENT_DELIM, ","))
+		goto out_free;
+
+	type = process_fields(event, &arg->flags.flags, &token);
+	if (test_type_token(type, token, EVENT_DELIM, ")"))
+		goto out_free;
+
+	free_token(token);
+	type = read_token_item(tok);
+	return type;
+
+out_free_field:
+	free_arg(field);
+out_free:
+	free_token(token);
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_symbols(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	struct print_arg *field;
+	enum event_type type;
+	char *token = NULL;
+
+	memset(arg, 0, sizeof(*arg));
+	arg->type = PRINT_SYMBOL;
+
+	field = alloc_arg();
+	if (!field) {
+		do_warning_event(event, "%s: not enough memory!", __func__);
+		goto out_free;
+	}
+
+	type = process_field_arg(event, field, &token);
+
+	if (test_type_token(type, token, EVENT_DELIM, ","))
+		goto out_free_field;
+
+	arg->symbol.field = field;
+
+	type = process_fields(event, &arg->symbol.symbols, &token);
+	if (test_type_token(type, token, EVENT_DELIM, ")"))
+		goto out_free;
+
+	free_token(token);
+	type = read_token_item(tok);
+	return type;
+
+out_free_field:
+	free_arg(field);
+out_free:
+	free_token(token);
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_hex(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	memset(arg, 0, sizeof(*arg));
+	arg->type = PRINT_HEX;
+
+	if (alloc_and_process_delim(event, ",", &arg->hex.field))
+		goto out;
+
+	if (alloc_and_process_delim(event, ")", &arg->hex.size))
+		goto free_field;
+
+	return read_token_item(tok);
+
+free_field:
+	free_arg(arg->hex.field);
+out:
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_int_array(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	memset(arg, 0, sizeof(*arg));
+	arg->type = PRINT_INT_ARRAY;
+
+	if (alloc_and_process_delim(event, ",", &arg->int_array.field))
+		goto out;
+
+	if (alloc_and_process_delim(event, ",", &arg->int_array.count))
+		goto free_field;
+
+	if (alloc_and_process_delim(event, ")", &arg->int_array.el_size))
+		goto free_size;
+
+	return read_token_item(tok);
+
+free_size:
+	free_arg(arg->int_array.count);
+free_field:
+	free_arg(arg->int_array.field);
+out:
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_dynamic_array(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	struct format_field *field;
+	enum event_type type;
+	char *token;
+
+	memset(arg, 0, sizeof(*arg));
+	arg->type = PRINT_DYNAMIC_ARRAY;
+
+	/*
+	 * The item within the parenthesis is another field that holds
+	 * the index into where the array starts.
+	 */
+	type = read_token(&token);
+	*tok = token;
+	if (type != EVENT_ITEM)
+		goto out_free;
+
+	/* Find the field */
+
+	field = pevent_find_field(event, token);
+	if (!field)
+		goto out_free;
+
+	arg->dynarray.field = field;
+	arg->dynarray.index = 0;
+
+	if (read_expected(EVENT_DELIM, ")") < 0)
+		goto out_free;
+
+	free_token(token);
+	type = read_token_item(&token);
+	*tok = token;
+	if (type != EVENT_OP || strcmp(token, "[") != 0)
+		return type;
+
+	free_token(token);
+	arg = alloc_arg();
+	if (!arg) {
+		do_warning_event(event, "%s: not enough memory!", __func__);
+		*tok = NULL;
+		return EVENT_ERROR;
+	}
+
+	type = process_arg(event, arg, &token);
+	if (type == EVENT_ERROR)
+		goto out_free_arg;
+
+	if (!test_type_token(type, token, EVENT_OP, "]"))
+		goto out_free_arg;
+
+	free_token(token);
+	type = read_token_item(tok);
+	return type;
+
+ out_free_arg:
+	free_arg(arg);
+ out_free:
+	free_token(token);
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_paren(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	struct print_arg *item_arg;
+	enum event_type type;
+	char *token;
+
+	type = process_arg(event, arg, &token);
+
+	if (type == EVENT_ERROR)
+		goto out_free;
+
+	if (type == EVENT_OP)
+		type = process_op(event, arg, &token);
+
+	if (type == EVENT_ERROR)
+		goto out_free;
+
+	if (test_type_token(type, token, EVENT_DELIM, ")"))
+		goto out_free;
+
+	free_token(token);
+	type = read_token_item(&token);
+
+	/*
+	 * If the next token is an item or another open paren, then
+	 * this was a typecast.
+	 */
+	if (event_item_type(type) ||
+	    (type == EVENT_DELIM && strcmp(token, "(") == 0)) {
+
+		/* make this a typecast and contine */
+
+		/* prevous must be an atom */
+		if (arg->type != PRINT_ATOM) {
+			do_warning_event(event, "previous needed to be PRINT_ATOM");
+			goto out_free;
+		}
+
+		item_arg = alloc_arg();
+		if (!item_arg) {
+			do_warning_event(event, "%s: not enough memory!",
+					 __func__);
+			goto out_free;
+		}
+
+		arg->type = PRINT_TYPE;
+		arg->typecast.type = arg->atom.atom;
+		arg->typecast.item = item_arg;
+		type = process_arg_token(event, item_arg, &token, type);
+
+	}
+
+	*tok = token;
+	return type;
+
+ out_free:
+	free_token(token);
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+
+static enum event_type
+process_str(struct event_format *event __maybe_unused, struct print_arg *arg,
+	    char **tok)
+{
+	enum event_type type;
+	char *token;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto out_free;
+
+	arg->type = PRINT_STRING;
+	arg->string.string = token;
+	arg->string.offset = -1;
+
+	if (read_expected(EVENT_DELIM, ")") < 0)
+		goto out_err;
+
+	type = read_token(&token);
+	*tok = token;
+
+	return type;
+
+ out_free:
+	free_token(token);
+ out_err:
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_bitmask(struct event_format *event __maybe_unused, struct print_arg *arg,
+	    char **tok)
+{
+	enum event_type type;
+	char *token;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto out_free;
+
+	arg->type = PRINT_BITMASK;
+	arg->bitmask.bitmask = token;
+	arg->bitmask.offset = -1;
+
+	if (read_expected(EVENT_DELIM, ")") < 0)
+		goto out_err;
+
+	type = read_token(&token);
+	*tok = token;
+
+	return type;
+
+ out_free:
+	free_token(token);
+ out_err:
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static struct pevent_function_handler *
+find_func_handler(struct pevent *pevent, char *func_name)
+{
+	struct pevent_function_handler *func;
+
+	if (!pevent)
+		return NULL;
+
+	for (func = pevent->func_handlers; func; func = func->next) {
+		if (strcmp(func->name, func_name) == 0)
+			break;
+	}
+
+	return func;
+}
+
+static void remove_func_handler(struct pevent *pevent, char *func_name)
+{
+	struct pevent_function_handler *func;
+	struct pevent_function_handler **next;
+
+	next = &pevent->func_handlers;
+	while ((func = *next)) {
+		if (strcmp(func->name, func_name) == 0) {
+			*next = func->next;
+			free_func_handle(func);
+			break;
+		}
+		next = &func->next;
+	}
+}
+
+static enum event_type
+process_func_handler(struct event_format *event, struct pevent_function_handler *func,
+		     struct print_arg *arg, char **tok)
+{
+	struct print_arg **next_arg;
+	struct print_arg *farg;
+	enum event_type type;
+	char *token;
+	int i;
+
+	arg->type = PRINT_FUNC;
+	arg->func.func = func;
+
+	*tok = NULL;
+
+	next_arg = &(arg->func.args);
+	for (i = 0; i < func->nr_args; i++) {
+		farg = alloc_arg();
+		if (!farg) {
+			do_warning_event(event, "%s: not enough memory!",
+					 __func__);
+			return EVENT_ERROR;
+		}
+
+		type = process_arg(event, farg, &token);
+		if (i < (func->nr_args - 1)) {
+			if (type != EVENT_DELIM || strcmp(token, ",") != 0) {
+				do_warning_event(event,
+					"Error: function '%s()' expects %d arguments but event %s only uses %d",
+					func->name, func->nr_args,
+					event->name, i + 1);
+				goto err;
+			}
+		} else {
+			if (type != EVENT_DELIM || strcmp(token, ")") != 0) {
+				do_warning_event(event,
+					"Error: function '%s()' only expects %d arguments but event %s has more",
+					func->name, func->nr_args, event->name);
+				goto err;
+			}
+		}
+
+		*next_arg = farg;
+		next_arg = &(farg->next);
+		free_token(token);
+	}
+
+	type = read_token(&token);
+	*tok = token;
+
+	return type;
+
+err:
+	free_arg(farg);
+	free_token(token);
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_function(struct event_format *event, struct print_arg *arg,
+		 char *token, char **tok)
+{
+	struct pevent_function_handler *func;
+
+	if (strcmp(token, "__print_flags") == 0) {
+		free_token(token);
+		is_flag_field = 1;
+		return process_flags(event, arg, tok);
+	}
+	if (strcmp(token, "__print_symbolic") == 0) {
+		free_token(token);
+		is_symbolic_field = 1;
+		return process_symbols(event, arg, tok);
+	}
+	if (strcmp(token, "__print_hex") == 0) {
+		free_token(token);
+		return process_hex(event, arg, tok);
+	}
+	if (strcmp(token, "__print_array") == 0) {
+		free_token(token);
+		return process_int_array(event, arg, tok);
+	}
+	if (strcmp(token, "__get_str") == 0) {
+		free_token(token);
+		return process_str(event, arg, tok);
+	}
+	if (strcmp(token, "__get_bitmask") == 0) {
+		free_token(token);
+		return process_bitmask(event, arg, tok);
+	}
+	if (strcmp(token, "__get_dynamic_array") == 0) {
+		free_token(token);
+		return process_dynamic_array(event, arg, tok);
+	}
+
+	func = find_func_handler(event->pevent, token);
+	if (func) {
+		free_token(token);
+		return process_func_handler(event, func, arg, tok);
+	}
+
+	do_warning_event(event, "function %s not defined", token);
+	free_token(token);
+	return EVENT_ERROR;
+}
+
+static enum event_type
+process_arg_token(struct event_format *event, struct print_arg *arg,
+		  char **tok, enum event_type type)
+{
+	char *token;
+	char *atom;
+
+	token = *tok;
+
+	switch (type) {
+	case EVENT_ITEM:
+		if (strcmp(token, "REC") == 0) {
+			free_token(token);
+			type = process_entry(event, arg, &token);
+			break;
+		}
+		atom = token;
+		/* test the next token */
+		type = read_token_item(&token);
+
+		/*
+		 * If the next token is a parenthesis, then this
+		 * is a function.
+		 */
+		if (type == EVENT_DELIM && strcmp(token, "(") == 0) {
+			free_token(token);
+			token = NULL;
+			/* this will free atom. */
+			type = process_function(event, arg, atom, &token);
+			break;
+		}
+		/* atoms can be more than one token long */
+		while (type == EVENT_ITEM) {
+			char *new_atom;
+			new_atom = realloc(atom,
+					   strlen(atom) + strlen(token) + 2);
+			if (!new_atom) {
+				free(atom);
+				*tok = NULL;
+				free_token(token);
+				return EVENT_ERROR;
+			}
+			atom = new_atom;
+			strcat(atom, " ");
+			strcat(atom, token);
+			free_token(token);
+			type = read_token_item(&token);
+		}
+
+		arg->type = PRINT_ATOM;
+		arg->atom.atom = atom;
+		break;
+
+	case EVENT_DQUOTE:
+	case EVENT_SQUOTE:
+		arg->type = PRINT_ATOM;
+		arg->atom.atom = token;
+		type = read_token_item(&token);
+		break;
+	case EVENT_DELIM:
+		if (strcmp(token, "(") == 0) {
+			free_token(token);
+			type = process_paren(event, arg, &token);
+			break;
+		}
+	case EVENT_OP:
+		/* handle single ops */
+		arg->type = PRINT_OP;
+		arg->op.op = token;
+		arg->op.left = NULL;
+		type = process_op(event, arg, &token);
+
+		/* On error, the op is freed */
+		if (type == EVENT_ERROR)
+			arg->op.op = NULL;
+
+		/* return error type if errored */
+		break;
+
+	case EVENT_ERROR ... EVENT_NEWLINE:
+	default:
+		do_warning_event(event, "unexpected type %d", type);
+		return EVENT_ERROR;
+	}
+	*tok = token;
+
+	return type;
+}
+
+static int event_read_print_args(struct event_format *event, struct print_arg **list)
+{
+	enum event_type type = EVENT_ERROR;
+	struct print_arg *arg;
+	char *token;
+	int args = 0;
+
+	do {
+		if (type == EVENT_NEWLINE) {
+			type = read_token_item(&token);
+			continue;
+		}
+
+		arg = alloc_arg();
+		if (!arg) {
+			do_warning_event(event, "%s: not enough memory!",
+					 __func__);
+			return -1;
+		}
+
+		type = process_arg(event, arg, &token);
+
+		if (type == EVENT_ERROR) {
+			free_token(token);
+			free_arg(arg);
+			return -1;
+		}
+
+		*list = arg;
+		args++;
+
+		if (type == EVENT_OP) {
+			type = process_op(event, arg, &token);
+			free_token(token);
+			if (type == EVENT_ERROR) {
+				*list = NULL;
+				free_arg(arg);
+				return -1;
+			}
+			list = &arg->next;
+			continue;
+		}
+
+		if (type == EVENT_DELIM && strcmp(token, ",") == 0) {
+			free_token(token);
+			*list = arg;
+			list = &arg->next;
+			continue;
+		}
+		break;
+	} while (type != EVENT_NONE);
+
+	if (type != EVENT_NONE && type != EVENT_ERROR)
+		free_token(token);
+
+	return args;
+}
+
+static int event_read_print(struct event_format *event)
+{
+	enum event_type type;
+	char *token;
+	int ret;
+
+	if (read_expected_item(EVENT_ITEM, "print") < 0)
+		return -1;
+
+	if (read_expected(EVENT_ITEM, "fmt") < 0)
+		return -1;
+
+	if (read_expected(EVENT_OP, ":") < 0)
+		return -1;
+
+	if (read_expect_type(EVENT_DQUOTE, &token) < 0)
+		goto fail;
+
+ concat:
+	event->print_fmt.format = token;
+	event->print_fmt.args = NULL;
+
+	/* ok to have no arg */
+	type = read_token_item(&token);
+
+	if (type == EVENT_NONE)
+		return 0;
+
+	/* Handle concatenation of print lines */
+	if (type == EVENT_DQUOTE) {
+		char *cat;
+
+		if (asprintf(&cat, "%s%s", event->print_fmt.format, token) < 0)
+			goto fail;
+		free_token(token);
+		free_token(event->print_fmt.format);
+		event->print_fmt.format = NULL;
+		token = cat;
+		goto concat;
+	}
+			     
+	if (test_type_token(type, token, EVENT_DELIM, ","))
+		goto fail;
+
+	free_token(token);
+
+	ret = event_read_print_args(event, &event->print_fmt.args);
+	if (ret < 0)
+		return -1;
+
+	return ret;
+
+ fail:
+	free_token(token);
+	return -1;
+}
+
+/**
+ * pevent_find_common_field - return a common field by event
+ * @event: handle for the event
+ * @name: the name of the common field to return
+ *
+ * Returns a common field from the event by the given @name.
+ * This only searchs the common fields and not all field.
+ */
+struct format_field *
+pevent_find_common_field(struct event_format *event, const char *name)
+{
+	struct format_field *format;
+
+	for (format = event->format.common_fields;
+	     format; format = format->next) {
+		if (strcmp(format->name, name) == 0)
+			break;
+	}
+
+	return format;
+}
+
+/**
+ * pevent_find_field - find a non-common field
+ * @event: handle for the event
+ * @name: the name of the non-common field
+ *
+ * Returns a non-common field by the given @name.
+ * This does not search common fields.
+ */
+struct format_field *
+pevent_find_field(struct event_format *event, const char *name)
+{
+	struct format_field *format;
+
+	for (format = event->format.fields;
+	     format; format = format->next) {
+		if (strcmp(format->name, name) == 0)
+			break;
+	}
+
+	return format;
+}
+
+/**
+ * pevent_find_any_field - find any field by name
+ * @event: handle for the event
+ * @name: the name of the field
+ *
+ * Returns a field by the given @name.
+ * This searchs the common field names first, then
+ * the non-common ones if a common one was not found.
+ */
+struct format_field *
+pevent_find_any_field(struct event_format *event, const char *name)
+{
+	struct format_field *format;
+
+	format = pevent_find_common_field(event, name);
+	if (format)
+		return format;
+	return pevent_find_field(event, name);
+}
+
+/**
+ * pevent_read_number - read a number from data
+ * @pevent: handle for the pevent
+ * @ptr: the raw data
+ * @size: the size of the data that holds the number
+ *
+ * Returns the number (converted to host) from the
+ * raw data.
+ */
+unsigned long long pevent_read_number(struct pevent *pevent,
+				      const void *ptr, int size)
+{
+	switch (size) {
+	case 1:
+		return *(unsigned char *)ptr;
+	case 2:
+		return data2host2(pevent, ptr);
+	case 4:
+		return data2host4(pevent, ptr);
+	case 8:
+		return data2host8(pevent, ptr);
+	default:
+		/* BUG! */
+		return 0;
+	}
+}
+
+/**
+ * pevent_read_number_field - read a number from data
+ * @field: a handle to the field
+ * @data: the raw data to read
+ * @value: the value to place the number in
+ *
+ * Reads raw data according to a field offset and size,
+ * and translates it into @value.
+ *
+ * Returns 0 on success, -1 otherwise.
+ */
+int pevent_read_number_field(struct format_field *field, const void *data,
+			     unsigned long long *value)
+{
+	if (!field)
+		return -1;
+	switch (field->size) {
+	case 1:
+	case 2:
+	case 4:
+	case 8:
+		*value = pevent_read_number(field->event->pevent,
+					    data + field->offset, field->size);
+		return 0;
+	default:
+		return -1;
+	}
+}
+
+static int get_common_info(struct pevent *pevent,
+			   const char *type, int *offset, int *size)
+{
+	struct event_format *event;
+	struct format_field *field;
+
+	/*
+	 * All events should have the same common elements.
+	 * Pick any event to find where the type is;
+	 */
+	if (!pevent->events) {
+		do_warning("no event_list!");
+		return -1;
+	}
+
+	event = pevent->events[0];
+	field = pevent_find_common_field(event, type);
+	if (!field)
+		return -1;
+
+	*offset = field->offset;
+	*size = field->size;
+
+	return 0;
+}
+
+static int __parse_common(struct pevent *pevent, void *data,
+			  int *size, int *offset, const char *name)
+{
+	int ret;
+
+	if (!*size) {
+		ret = get_common_info(pevent, name, offset, size);
+		if (ret < 0)
+			return ret;
+	}
+	return pevent_read_number(pevent, data + *offset, *size);
+}
+
+static int trace_parse_common_type(struct pevent *pevent, void *data)
+{
+	return __parse_common(pevent, data,
+			      &pevent->type_size, &pevent->type_offset,
+			      "common_type");
+}
+
+static int parse_common_pid(struct pevent *pevent, void *data)
+{
+	return __parse_common(pevent, data,
+			      &pevent->pid_size, &pevent->pid_offset,
+			      "common_pid");
+}
+
+static int parse_common_pc(struct pevent *pevent, void *data)
+{
+	return __parse_common(pevent, data,
+			      &pevent->pc_size, &pevent->pc_offset,
+			      "common_preempt_count");
+}
+
+static int parse_common_flags(struct pevent *pevent, void *data)
+{
+	return __parse_common(pevent, data,
+			      &pevent->flags_size, &pevent->flags_offset,
+			      "common_flags");
+}
+
+static int parse_common_lock_depth(struct pevent *pevent, void *data)
+{
+	return __parse_common(pevent, data,
+			      &pevent->ld_size, &pevent->ld_offset,
+			      "common_lock_depth");
+}
+
+static int parse_common_migrate_disable(struct pevent *pevent, void *data)
+{
+	return __parse_common(pevent, data,
+			      &pevent->ld_size, &pevent->ld_offset,
+			      "common_migrate_disable");
+}
+
+static int events_id_cmp(const void *a, const void *b);
+
+/**
+ * pevent_find_event - find an event by given id
+ * @pevent: a handle to the pevent
+ * @id: the id of the event
+ *
+ * Returns an event that has a given @id.
+ */
+struct event_format *pevent_find_event(struct pevent *pevent, int id)
+{
+	struct event_format **eventptr;
+	struct event_format key;
+	struct event_format *pkey = &key;
+
+	/* Check cache first */
+	if (pevent->last_event && pevent->last_event->id == id)
+		return pevent->last_event;
+
+	key.id = id;
+
+	eventptr = bsearch(&pkey, pevent->events, pevent->nr_events,
+			   sizeof(*pevent->events), events_id_cmp);
+
+	if (eventptr) {
+		pevent->last_event = *eventptr;
+		return *eventptr;
+	}
+
+	return NULL;
+}
+
+/**
+ * pevent_find_event_by_name - find an event by given name
+ * @pevent: a handle to the pevent
+ * @sys: the system name to search for
+ * @name: the name of the event to search for
+ *
+ * This returns an event with a given @name and under the system
+ * @sys. If @sys is NULL the first event with @name is returned.
+ */
+struct event_format *
+pevent_find_event_by_name(struct pevent *pevent,
+			  const char *sys, const char *name)
+{
+	struct event_format *event;
+	int i;
+
+	if (pevent->last_event &&
+	    strcmp(pevent->last_event->name, name) == 0 &&
+	    (!sys || strcmp(pevent->last_event->system, sys) == 0))
+		return pevent->last_event;
+
+	for (i = 0; i < pevent->nr_events; i++) {
+		event = pevent->events[i];
+		if (strcmp(event->name, name) == 0) {
+			if (!sys)
+				break;
+			if (strcmp(event->system, sys) == 0)
+				break;
+		}
+	}
+	if (i == pevent->nr_events)
+		event = NULL;
+
+	pevent->last_event = event;
+	return event;
+}
+
+static unsigned long long
+eval_num_arg(void *data, int size, struct event_format *event, struct print_arg *arg)
+{
+	struct pevent *pevent = event->pevent;
+	unsigned long long val = 0;
+	unsigned long long left, right;
+	struct print_arg *typearg = NULL;
+	struct print_arg *larg;
+	unsigned long offset;
+	unsigned int field_size;
+
+	switch (arg->type) {
+	case PRINT_NULL:
+		/* ?? */
+		return 0;
+	case PRINT_ATOM:
+		return strtoull(arg->atom.atom, NULL, 0);
+	case PRINT_FIELD:
+		if (!arg->field.field) {
+			arg->field.field = pevent_find_any_field(event, arg->field.name);
+			if (!arg->field.field)
+				goto out_warning_field;
+			
+		}
+		/* must be a number */
+		val = pevent_read_number(pevent, data + arg->field.field->offset,
+				arg->field.field->size);
+		break;
+	case PRINT_FLAGS:
+	case PRINT_SYMBOL:
+	case PRINT_INT_ARRAY:
+	case PRINT_HEX:
+		break;
+	case PRINT_TYPE:
+		val = eval_num_arg(data, size, event, arg->typecast.item);
+		return eval_type(val, arg, 0);
+	case PRINT_STRING:
+	case PRINT_BSTRING:
+	case PRINT_BITMASK:
+		return 0;
+	case PRINT_FUNC: {
+		struct trace_seq s;
+		trace_seq_init(&s);
+		val = process_defined_func(&s, data, size, event, arg);
+		trace_seq_destroy(&s);
+		return val;
+	}
+	case PRINT_OP:
+		if (strcmp(arg->op.op, "[") == 0) {
+			/*
+			 * Arrays are special, since we don't want
+			 * to read the arg as is.
+			 */
+			right = eval_num_arg(data, size, event, arg->op.right);
+
+			/* handle typecasts */
+			larg = arg->op.left;
+			while (larg->type == PRINT_TYPE) {
+				if (!typearg)
+					typearg = larg;
+				larg = larg->typecast.item;
+			}
+
+			/* Default to long size */
+			field_size = pevent->long_size;
+
+			switch (larg->type) {
+			case PRINT_DYNAMIC_ARRAY:
+				offset = pevent_read_number(pevent,
+						   data + larg->dynarray.field->offset,
+						   larg->dynarray.field->size);
+				if (larg->dynarray.field->elementsize)
+					field_size = larg->dynarray.field->elementsize;
+				/*
+				 * The actual length of the dynamic array is stored
+				 * in the top half of the field, and the offset
+				 * is in the bottom half of the 32 bit field.
+				 */
+				offset &= 0xffff;
+				offset += right;
+				break;
+			case PRINT_FIELD:
+				if (!larg->field.field) {
+					larg->field.field =
+						pevent_find_any_field(event, larg->field.name);
+					if (!larg->field.field) {
+						arg = larg;
+						goto out_warning_field;
+					}
+				}
+				field_size = larg->field.field->elementsize;
+				offset = larg->field.field->offset +
+					right * larg->field.field->elementsize;
+				break;
+			default:
+				goto default_op; /* oops, all bets off */
+			}
+			val = pevent_read_number(pevent,
+						 data + offset, field_size);
+			if (typearg)
+				val = eval_type(val, typearg, 1);
+			break;
+		} else if (strcmp(arg->op.op, "?") == 0) {
+			left = eval_num_arg(data, size, event, arg->op.left);
+			arg = arg->op.right;
+			if (left)
+				val = eval_num_arg(data, size, event, arg->op.left);
+			else
+				val = eval_num_arg(data, size, event, arg->op.right);
+			break;
+		}
+ default_op:
+		left = eval_num_arg(data, size, event, arg->op.left);
+		right = eval_num_arg(data, size, event, arg->op.right);
+		switch (arg->op.op[0]) {
+		case '!':
+			switch (arg->op.op[1]) {
+			case 0:
+				val = !right;
+				break;
+			case '=':
+				val = left != right;
+				break;
+			default:
+				goto out_warning_op;
+			}
+			break;
+		case '~':
+			val = ~right;
+			break;
+		case '|':
+			if (arg->op.op[1])
+				val = left || right;
+			else
+				val = left | right;
+			break;
+		case '&':
+			if (arg->op.op[1])
+				val = left && right;
+			else
+				val = left & right;
+			break;
+		case '<':
+			switch (arg->op.op[1]) {
+			case 0:
+				val = left < right;
+				break;
+			case '<':
+				val = left << right;
+				break;
+			case '=':
+				val = left <= right;
+				break;
+			default:
+				goto out_warning_op;
+			}
+			break;
+		case '>':
+			switch (arg->op.op[1]) {
+			case 0:
+				val = left > right;
+				break;
+			case '>':
+				val = left >> right;
+				break;
+			case '=':
+				val = left >= right;
+				break;
+			default:
+				goto out_warning_op;
+			}
+			break;
+		case '=':
+			if (arg->op.op[1] != '=')
+				goto out_warning_op;
+
+			val = left == right;
+			break;
+		case '-':
+			val = left - right;
+			break;
+		case '+':
+			val = left + right;
+			break;
+		case '/':
+			val = left / right;
+			break;
+		case '*':
+			val = left * right;
+			break;
+		default:
+			goto out_warning_op;
+		}
+		break;
+	case PRINT_DYNAMIC_ARRAY:
+		/* Without [], we pass the address to the dynamic data */
+		offset = pevent_read_number(pevent,
+					    data + arg->dynarray.field->offset,
+					    arg->dynarray.field->size);
+		/*
+		 * The actual length of the dynamic array is stored
+		 * in the top half of the field, and the offset
+		 * is in the bottom half of the 32 bit field.
+		 */
+		offset &= 0xffff;
+		val = (unsigned long long)((unsigned long)data + offset);
+		break;
+	default: /* not sure what to do there */
+		return 0;
+	}
+	return val;
+
+out_warning_op:
+	do_warning_event(event, "%s: unknown op '%s'", __func__, arg->op.op);
+	return 0;
+
+out_warning_field:
+	do_warning_event(event, "%s: field %s not found",
+			 __func__, arg->field.name);
+	return 0;
+}
+
+struct flag {
+	const char *name;
+	unsigned long long value;
+};
+
+static const struct flag flags[] = {
+	{ "HI_SOFTIRQ", 0 },
+	{ "TIMER_SOFTIRQ", 1 },
+	{ "NET_TX_SOFTIRQ", 2 },
+	{ "NET_RX_SOFTIRQ", 3 },
+	{ "BLOCK_SOFTIRQ", 4 },
+	{ "BLOCK_IOPOLL_SOFTIRQ", 5 },
+	{ "TASKLET_SOFTIRQ", 6 },
+	{ "SCHED_SOFTIRQ", 7 },
+	{ "HRTIMER_SOFTIRQ", 8 },
+	{ "RCU_SOFTIRQ", 9 },
+
+	{ "HRTIMER_NORESTART", 0 },
+	{ "HRTIMER_RESTART", 1 },
+};
+
+static long long eval_flag(const char *flag)
+{
+	int i;
+
+	/*
+	 * Some flags in the format files do not get converted.
+	 * If the flag is not numeric, see if it is something that
+	 * we already know about.
+	 */
+	if (isdigit(flag[0]))
+		return strtoull(flag, NULL, 0);
+
+	for (i = 0; i < (int)(sizeof(flags)/sizeof(flags[0])); i++)
+		if (strcmp(flags[i].name, flag) == 0)
+			return flags[i].value;
+
+	return -1LL;
+}
+
+static void print_str_to_seq(struct trace_seq *s, const char *format,
+			     int len_arg, const char *str)
+{
+	if (len_arg >= 0)
+		trace_seq_printf(s, format, len_arg, str);
+	else
+		trace_seq_printf(s, format, str);
+}
+
+static void print_bitmask_to_seq(struct pevent *pevent,
+				 struct trace_seq *s, const char *format,
+				 int len_arg, const void *data, int size)
+{
+	int nr_bits = size * 8;
+	int str_size = (nr_bits + 3) / 4;
+	int len = 0;
+	char buf[3];
+	char *str;
+	int index;
+	int i;
+
+	/*
+	 * The kernel likes to put in commas every 32 bits, we
+	 * can do the same.
+	 */
+	str_size += (nr_bits - 1) / 32;
+
+	str = malloc(str_size + 1);
+	if (!str) {
+		do_warning("%s: not enough memory!", __func__);
+		return;
+	}
+	str[str_size] = 0;
+
+	/* Start out with -2 for the two chars per byte */
+	for (i = str_size - 2; i >= 0; i -= 2) {
+		/*
+		 * data points to a bit mask of size bytes.
+		 * In the kernel, this is an array of long words, thus
+		 * endianess is very important.
+		 */
+		if (pevent->file_bigendian)
+			index = size - (len + 1);
+		else
+			index = len;
+
+		snprintf(buf, 3, "%02x", *((unsigned char *)data + index));
+		memcpy(str + i, buf, 2);
+		len++;
+		if (!(len & 3) && i > 0) {
+			i--;
+			str[i] = ',';
+		}
+	}
+
+	if (len_arg >= 0)
+		trace_seq_printf(s, format, len_arg, str);
+	else
+		trace_seq_printf(s, format, str);
+
+	free(str);
+}
+
+static void print_str_arg(struct trace_seq *s, void *data, int size,
+			  struct event_format *event, const char *format,
+			  int len_arg, struct print_arg *arg)
+{
+	struct pevent *pevent = event->pevent;
+	struct print_flag_sym *flag;
+	struct format_field *field;
+	struct printk_map *printk;
+	long long val, fval;
+	unsigned long addr;
+	char *str;
+	unsigned char *hex;
+	int print;
+	int i, len;
+
+	switch (arg->type) {
+	case PRINT_NULL:
+		/* ?? */
+		return;
+	case PRINT_ATOM:
+		print_str_to_seq(s, format, len_arg, arg->atom.atom);
+		return;
+	case PRINT_FIELD:
+		field = arg->field.field;
+		if (!field) {
+			field = pevent_find_any_field(event, arg->field.name);
+			if (!field) {
+				str = arg->field.name;
+				goto out_warning_field;
+			}
+			arg->field.field = field;
+		}
+		/* Zero sized fields, mean the rest of the data */
+		len = field->size ? : size - field->offset;
+
+		/*
+		 * Some events pass in pointers. If this is not an array
+		 * and the size is the same as long_size, assume that it
+		 * is a pointer.
+		 */
+		if (!(field->flags & FIELD_IS_ARRAY) &&
+		    field->size == pevent->long_size) {
+			addr = *(unsigned long *)(data + field->offset);
+			/* Check if it matches a print format */
+			printk = find_printk(pevent, addr);
+			if (printk)
+				trace_seq_puts(s, printk->printk);
+			else
+				trace_seq_printf(s, "%lx", addr);
+			break;
+		}
+		str = malloc(len + 1);
+		if (!str) {
+			do_warning_event(event, "%s: not enough memory!",
+					 __func__);
+			return;
+		}
+		memcpy(str, data + field->offset, len);
+		str[len] = 0;
+		print_str_to_seq(s, format, len_arg, str);
+		free(str);
+		break;
+	case PRINT_FLAGS:
+		val = eval_num_arg(data, size, event, arg->flags.field);
+		print = 0;
+		for (flag = arg->flags.flags; flag; flag = flag->next) {
+			fval = eval_flag(flag->value);
+			if (!val && fval < 0) {
+				print_str_to_seq(s, format, len_arg, flag->str);
+				break;
+			}
+			if (fval > 0 && (val & fval) == fval) {
+				if (print && arg->flags.delim)
+					trace_seq_puts(s, arg->flags.delim);
+				print_str_to_seq(s, format, len_arg, flag->str);
+				print = 1;
+				val &= ~fval;
+			}
+		}
+		break;
+	case PRINT_SYMBOL:
+		val = eval_num_arg(data, size, event, arg->symbol.field);
+		for (flag = arg->symbol.symbols; flag; flag = flag->next) {
+			fval = eval_flag(flag->value);
+			if (val == fval) {
+				print_str_to_seq(s, format, len_arg, flag->str);
+				break;
+			}
+		}
+		break;
+	case PRINT_HEX:
+		if (arg->hex.field->type == PRINT_DYNAMIC_ARRAY) {
+			unsigned long offset;
+			offset = pevent_read_number(pevent,
+				data + arg->hex.field->dynarray.field->offset,
+				arg->hex.field->dynarray.field->size);
+			hex = data + (offset & 0xffff);
+		} else {
+			field = arg->hex.field->field.field;
+			if (!field) {
+				str = arg->hex.field->field.name;
+				field = pevent_find_any_field(event, str);
+				if (!field)
+					goto out_warning_field;
+				arg->hex.field->field.field = field;
+			}
+			hex = data + field->offset;
+		}
+		len = eval_num_arg(data, size, event, arg->hex.size);
+		for (i = 0; i < len; i++) {
+			if (i)
+				trace_seq_putc(s, ' ');
+			trace_seq_printf(s, "%02x", hex[i]);
+		}
+		break;
+
+	case PRINT_INT_ARRAY: {
+		void *num;
+		int el_size;
+
+		if (arg->int_array.field->type == PRINT_DYNAMIC_ARRAY) {
+			unsigned long offset;
+			struct format_field *field =
+				arg->int_array.field->dynarray.field;
+			offset = pevent_read_number(pevent,
+						    data + field->offset,
+						    field->size);
+			num = data + (offset & 0xffff);
+		} else {
+			field = arg->int_array.field->field.field;
+			if (!field) {
+				str = arg->int_array.field->field.name;
+				field = pevent_find_any_field(event, str);
+				if (!field)
+					goto out_warning_field;
+				arg->int_array.field->field.field = field;
+			}
+			num = data + field->offset;
+		}
+		len = eval_num_arg(data, size, event, arg->int_array.count);
+		el_size = eval_num_arg(data, size, event,
+				       arg->int_array.el_size);
+		for (i = 0; i < len; i++) {
+			if (i)
+				trace_seq_putc(s, ' ');
+
+			if (el_size == 1) {
+				trace_seq_printf(s, "%u", *(uint8_t *)num);
+			} else if (el_size == 2) {
+				trace_seq_printf(s, "%u", *(uint16_t *)num);
+			} else if (el_size == 4) {
+				trace_seq_printf(s, "%u", *(uint32_t *)num);
+			} else if (el_size == 8) {
+				trace_seq_printf(s, "%"PRIu64, *(uint64_t *)num);
+			} else {
+				trace_seq_printf(s, "BAD SIZE:%d 0x%x",
+						 el_size, *(uint8_t *)num);
+				el_size = 1;
+			}
+
+			num += el_size;
+		}
+		break;
+	}
+	case PRINT_TYPE:
+		break;
+	case PRINT_STRING: {
+		int str_offset;
+
+		if (arg->string.offset == -1) {
+			struct format_field *f;
+
+			f = pevent_find_any_field(event, arg->string.string);
+			arg->string.offset = f->offset;
+		}
+		str_offset = data2host4(pevent, data + arg->string.offset);
+		str_offset &= 0xffff;
+		print_str_to_seq(s, format, len_arg, ((char *)data) + str_offset);
+		break;
+	}
+	case PRINT_BSTRING:
+		print_str_to_seq(s, format, len_arg, arg->string.string);
+		break;
+	case PRINT_BITMASK: {
+		int bitmask_offset;
+		int bitmask_size;
+
+		if (arg->bitmask.offset == -1) {
+			struct format_field *f;
+
+			f = pevent_find_any_field(event, arg->bitmask.bitmask);
+			arg->bitmask.offset = f->offset;
+		}
+		bitmask_offset = data2host4(pevent, data + arg->bitmask.offset);
+		bitmask_size = bitmask_offset >> 16;
+		bitmask_offset &= 0xffff;
+		print_bitmask_to_seq(pevent, s, format, len_arg,
+				     data + bitmask_offset, bitmask_size);
+		break;
+	}
+	case PRINT_OP:
+		/*
+		 * The only op for string should be ? :
+		 */
+		if (arg->op.op[0] != '?')
+			return;
+		val = eval_num_arg(data, size, event, arg->op.left);
+		if (val)
+			print_str_arg(s, data, size, event,
+				      format, len_arg, arg->op.right->op.left);
+		else
+			print_str_arg(s, data, size, event,
+				      format, len_arg, arg->op.right->op.right);
+		break;
+	case PRINT_FUNC:
+		process_defined_func(s, data, size, event, arg);
+		break;
+	default:
+		/* well... */
+		break;
+	}
+
+	return;
+
+out_warning_field:
+	do_warning_event(event, "%s: field %s not found",
+			 __func__, arg->field.name);
+}
+
+static unsigned long long
+process_defined_func(struct trace_seq *s, void *data, int size,
+		     struct event_format *event, struct print_arg *arg)
+{
+	struct pevent_function_handler *func_handle = arg->func.func;
+	struct pevent_func_params *param;
+	unsigned long long *args;
+	unsigned long long ret;
+	struct print_arg *farg;
+	struct trace_seq str;
+	struct save_str {
+		struct save_str *next;
+		char *str;
+	} *strings = NULL, *string;
+	int i;
+
+	if (!func_handle->nr_args) {
+		ret = (*func_handle->func)(s, NULL);
+		goto out;
+	}
+
+	farg = arg->func.args;
+	param = func_handle->params;
+
+	ret = ULLONG_MAX;
+	args = malloc(sizeof(*args) * func_handle->nr_args);
+	if (!args)
+		goto out;
+
+	for (i = 0; i < func_handle->nr_args; i++) {
+		switch (param->type) {
+		case PEVENT_FUNC_ARG_INT:
+		case PEVENT_FUNC_ARG_LONG:
+		case PEVENT_FUNC_ARG_PTR:
+			args[i] = eval_num_arg(data, size, event, farg);
+			break;
+		case PEVENT_FUNC_ARG_STRING:
+			trace_seq_init(&str);
+			print_str_arg(&str, data, size, event, "%s", -1, farg);
+			trace_seq_terminate(&str);
+			string = malloc(sizeof(*string));
+			if (!string) {
+				do_warning_event(event, "%s(%d): malloc str",
+						 __func__, __LINE__);
+				goto out_free;
+			}
+			string->next = strings;
+			string->str = strdup(str.buffer);
+			if (!string->str) {
+				free(string);
+				do_warning_event(event, "%s(%d): malloc str",
+						 __func__, __LINE__);
+				goto out_free;
+			}
+			args[i] = (uintptr_t)string->str;
+			strings = string;
+			trace_seq_destroy(&str);
+			break;
+		default:
+			/*
+			 * Something went totally wrong, this is not
+			 * an input error, something in this code broke.
+			 */
+			do_warning_event(event, "Unexpected end of arguments\n");
+			goto out_free;
+		}
+		farg = farg->next;
+		param = param->next;
+	}
+
+	ret = (*func_handle->func)(s, args);
+out_free:
+	free(args);
+	while (strings) {
+		string = strings;
+		strings = string->next;
+		free(string->str);
+		free(string);
+	}
+
+ out:
+	/* TBD : handle return type here */
+	return ret;
+}
+
+static void free_args(struct print_arg *args)
+{
+	struct print_arg *next;
+
+	while (args) {
+		next = args->next;
+
+		free_arg(args);
+		args = next;
+	}
+}
+
+static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struct event_format *event)
+{
+	struct pevent *pevent = event->pevent;
+	struct format_field *field, *ip_field;
+	struct print_arg *args, *arg, **next;
+	unsigned long long ip, val;
+	char *ptr;
+	void *bptr;
+	int vsize;
+
+	field = pevent->bprint_buf_field;
+	ip_field = pevent->bprint_ip_field;
+
+	if (!field) {
+		field = pevent_find_field(event, "buf");
+		if (!field) {
+			do_warning_event(event, "can't find buffer field for binary printk");
+			return NULL;
+		}
+		ip_field = pevent_find_field(event, "ip");
+		if (!ip_field) {
+			do_warning_event(event, "can't find ip field for binary printk");
+			return NULL;
+		}
+		pevent->bprint_buf_field = field;
+		pevent->bprint_ip_field = ip_field;
+	}
+
+	ip = pevent_read_number(pevent, data + ip_field->offset, ip_field->size);
+
+	/*
+	 * The first arg is the IP pointer.
+	 */
+	args = alloc_arg();
+	if (!args) {
+		do_warning_event(event, "%s(%d): not enough memory!",
+				 __func__, __LINE__);
+		return NULL;
+	}
+	arg = args;
+	arg->next = NULL;
+	next = &arg->next;
+
+	arg->type = PRINT_ATOM;
+		
+	if (asprintf(&arg->atom.atom, "%lld", ip) < 0)
+		goto out_free;
+
+	/* skip the first "%ps: " */
+	for (ptr = fmt + 5, bptr = data + field->offset;
+	     bptr < data + size && *ptr; ptr++) {
+		int ls = 0;
+
+		if (*ptr == '%') {
+ process_again:
+			ptr++;
+			switch (*ptr) {
+			case '%':
+				break;
+			case 'l':
+				ls++;
+				goto process_again;
+			case 'L':
+				ls = 2;
+				goto process_again;
+			case '0' ... '9':
+				goto process_again;
+			case '.':
+				goto process_again;
+			case 'z':
+			case 'Z':
+				ls = 1;
+				goto process_again;
+			case 'p':
+				ls = 1;
+				/* fall through */
+			case 'd':
+			case 'u':
+			case 'x':
+			case 'i':
+				switch (ls) {
+				case 0:
+					vsize = 4;
+					break;
+				case 1:
+					vsize = pevent->long_size;
+					break;
+				case 2:
+					vsize = 8;
+					break;
+				default:
+					vsize = ls; /* ? */
+					break;
+				}
+			/* fall through */
+			case '*':
+				if (*ptr == '*')
+					vsize = 4;
+
+				/* the pointers are always 4 bytes aligned */
+				bptr = (void *)(((unsigned long)bptr + 3) &
+						~3);
+				val = pevent_read_number(pevent, bptr, vsize);
+				bptr += vsize;
+				arg = alloc_arg();
+				if (!arg) {
+					do_warning_event(event, "%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
+				arg->next = NULL;
+				arg->type = PRINT_ATOM;
+				if (asprintf(&arg->atom.atom, "%lld", val) < 0) {
+					free(arg);
+					goto out_free;
+				}
+				*next = arg;
+				next = &arg->next;
+				/*
+				 * The '*' case means that an arg is used as the length.
+				 * We need to continue to figure out for what.
+				 */
+				if (*ptr == '*')
+					goto process_again;
+
+				break;
+			case 's':
+				arg = alloc_arg();
+				if (!arg) {
+					do_warning_event(event, "%s(%d): not enough memory!",
+						   __func__, __LINE__);
+					goto out_free;
+				}
+				arg->next = NULL;
+				arg->type = PRINT_BSTRING;
+				arg->string.string = strdup(bptr);
+				if (!arg->string.string)
+					goto out_free;
+				bptr += strlen(bptr) + 1;
+				*next = arg;
+				next = &arg->next;
+			default:
+				break;
+			}
+		}
+	}
+
+	return args;
+
+out_free:
+	free_args(args);
+	return NULL;
+}
+
+static char *
+get_bprint_format(void *data, int size __maybe_unused,
+		  struct event_format *event)
+{
+	struct pevent *pevent = event->pevent;
+	unsigned long long addr;
+	struct format_field *field;
+	struct printk_map *printk;
+	char *format;
+
+	field = pevent->bprint_fmt_field;
+
+	if (!field) {
+		field = pevent_find_field(event, "fmt");
+		if (!field) {
+			do_warning_event(event, "can't find format field for binary printk");
+			return NULL;
+		}
+		pevent->bprint_fmt_field = field;
+	}
+
+	addr = pevent_read_number(pevent, data + field->offset, field->size);
+
+	printk = find_printk(pevent, addr);
+	if (!printk) {
+		if (asprintf(&format, "%%pf: (NO FORMAT FOUND at %llx)\n", addr) < 0)
+			return NULL;
+		return format;
+	}
+
+	if (asprintf(&format, "%s: %s", "%pf", printk->printk) < 0)
+		return NULL;
+
+	return format;
+}
+
+static void print_mac_arg(struct trace_seq *s, int mac, void *data, int size,
+			  struct event_format *event, struct print_arg *arg)
+{
+	unsigned char *buf;
+	const char *fmt = "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x";
+
+	if (arg->type == PRINT_FUNC) {
+		process_defined_func(s, data, size, event, arg);
+		return;
+	}
+
+	if (arg->type != PRINT_FIELD) {
+		trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d",
+				 arg->type);
+		return;
+	}
+
+	if (mac == 'm')
+		fmt = "%.2x%.2x%.2x%.2x%.2x%.2x";
+	if (!arg->field.field) {
+		arg->field.field =
+			pevent_find_any_field(event, arg->field.name);
+		if (!arg->field.field) {
+			do_warning_event(event, "%s: field %s not found",
+					 __func__, arg->field.name);
+			return;
+		}
+	}
+	if (arg->field.field->size != 6) {
+		trace_seq_printf(s, "INVALIDMAC");
+		return;
+	}
+	buf = data + arg->field.field->offset;
+	trace_seq_printf(s, fmt, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]);
+}
+
+static void print_ip4_addr(struct trace_seq *s, char i, unsigned char *buf)
+{
+	const char *fmt;
+
+	if (i == 'i')
+		fmt = "%03d.%03d.%03d.%03d";
+	else
+		fmt = "%d.%d.%d.%d";
+
+	trace_seq_printf(s, fmt, buf[0], buf[1], buf[2], buf[3]);
+}
+
+static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
+{
+	return ((unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
+		(unsigned long)(a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0UL;
+}
+
+static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
+{
+	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
+}
+
+static void print_ip6c_addr(struct trace_seq *s, unsigned char *addr)
+{
+	int i, j, range;
+	unsigned char zerolength[8];
+	int longest = 1;
+	int colonpos = -1;
+	uint16_t word;
+	uint8_t hi, lo;
+	bool needcolon = false;
+	bool useIPv4;
+	struct in6_addr in6;
+
+	memcpy(&in6, addr, sizeof(struct in6_addr));
+
+	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
+
+	memset(zerolength, 0, sizeof(zerolength));
+
+	if (useIPv4)
+		range = 6;
+	else
+		range = 8;
+
+	/* find position of longest 0 run */
+	for (i = 0; i < range; i++) {
+		for (j = i; j < range; j++) {
+			if (in6.s6_addr16[j] != 0)
+				break;
+			zerolength[i]++;
+		}
+	}
+	for (i = 0; i < range; i++) {
+		if (zerolength[i] > longest) {
+			longest = zerolength[i];
+			colonpos = i;
+		}
+	}
+	if (longest == 1)		/* don't compress a single 0 */
+		colonpos = -1;
+
+	/* emit address */
+	for (i = 0; i < range; i++) {
+		if (i == colonpos) {
+			if (needcolon || i == 0)
+				trace_seq_printf(s, ":");
+			trace_seq_printf(s, ":");
+			needcolon = false;
+			i += longest - 1;
+			continue;
+		}
+		if (needcolon) {
+			trace_seq_printf(s, ":");
+			needcolon = false;
+		}
+		/* hex u16 without leading 0s */
+		word = ntohs(in6.s6_addr16[i]);
+		hi = word >> 8;
+		lo = word & 0xff;
+		if (hi)
+			trace_seq_printf(s, "%x%02x", hi, lo);
+		else
+			trace_seq_printf(s, "%x", lo);
+
+		needcolon = true;
+	}
+
+	if (useIPv4) {
+		if (needcolon)
+			trace_seq_printf(s, ":");
+		print_ip4_addr(s, 'I', &in6.s6_addr[12]);
+	}
+
+	return;
+}
+
+static void print_ip6_addr(struct trace_seq *s, char i, unsigned char *buf)
+{
+	int j;
+
+	for (j = 0; j < 16; j += 2) {
+		trace_seq_printf(s, "%02x%02x", buf[j], buf[j+1]);
+		if (i == 'I' && j < 14)
+			trace_seq_printf(s, ":");
+	}
+}
+
+/*
+ * %pi4   print an IPv4 address with leading zeros
+ * %pI4   print an IPv4 address without leading zeros
+ * %pi6   print an IPv6 address without colons
+ * %pI6   print an IPv6 address with colons
+ * %pI6c  print an IPv6 address in compressed form with colons
+ * %pISpc print an IP address based on sockaddr; p adds port.
+ */
+static int print_ipv4_arg(struct trace_seq *s, const char *ptr, char i,
+			  void *data, int size, struct event_format *event,
+			  struct print_arg *arg)
+{
+	unsigned char *buf;
+
+	if (arg->type == PRINT_FUNC) {
+		process_defined_func(s, data, size, event, arg);
+		return 0;
+	}
+
+	if (arg->type != PRINT_FIELD) {
+		trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+		return 0;
+	}
+
+	if (!arg->field.field) {
+		arg->field.field =
+			pevent_find_any_field(event, arg->field.name);
+		if (!arg->field.field) {
+			do_warning("%s: field %s not found",
+				   __func__, arg->field.name);
+			return 0;
+		}
+	}
+
+	buf = data + arg->field.field->offset;
+
+	if (arg->field.field->size != 4) {
+		trace_seq_printf(s, "INVALIDIPv4");
+		return 0;
+	}
+	print_ip4_addr(s, i, buf);
+
+	return 0;
+}
+
+static int print_ipv6_arg(struct trace_seq *s, const char *ptr, char i,
+			  void *data, int size, struct event_format *event,
+			  struct print_arg *arg)
+{
+	char have_c = 0;
+	unsigned char *buf;
+	int rc = 0;
+
+	/* pI6c */
+	if (i == 'I' && *ptr == 'c') {
+		have_c = 1;
+		ptr++;
+		rc++;
+	}
+
+	if (arg->type == PRINT_FUNC) {
+		process_defined_func(s, data, size, event, arg);
+		return rc;
+	}
+
+	if (arg->type != PRINT_FIELD) {
+		trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+		return rc;
+	}
+
+	if (!arg->field.field) {
+		arg->field.field =
+			pevent_find_any_field(event, arg->field.name);
+		if (!arg->field.field) {
+			do_warning("%s: field %s not found",
+				   __func__, arg->field.name);
+			return rc;
+		}
+	}
+
+	buf = data + arg->field.field->offset;
+
+	if (arg->field.field->size != 16) {
+		trace_seq_printf(s, "INVALIDIPv6");
+		return rc;
+	}
+
+	if (have_c)
+		print_ip6c_addr(s, buf);
+	else
+		print_ip6_addr(s, i, buf);
+
+	return rc;
+}
+
+static int print_ipsa_arg(struct trace_seq *s, const char *ptr, char i,
+			  void *data, int size, struct event_format *event,
+			  struct print_arg *arg)
+{
+	char have_c = 0, have_p = 0;
+	unsigned char *buf;
+	struct sockaddr_storage *sa;
+	int rc = 0;
+
+	/* pISpc */
+	if (i == 'I') {
+		if (*ptr == 'p') {
+			have_p = 1;
+			ptr++;
+			rc++;
+		}
+		if (*ptr == 'c') {
+			have_c = 1;
+			ptr++;
+			rc++;
+		}
+	}
+
+	if (arg->type == PRINT_FUNC) {
+		process_defined_func(s, data, size, event, arg);
+		return rc;
+	}
+
+	if (arg->type != PRINT_FIELD) {
+		trace_seq_printf(s, "ARG TYPE NOT FIELD BUT %d", arg->type);
+		return rc;
+	}
+
+	if (!arg->field.field) {
+		arg->field.field =
+			pevent_find_any_field(event, arg->field.name);
+		if (!arg->field.field) {
+			do_warning("%s: field %s not found",
+				   __func__, arg->field.name);
+			return rc;
+		}
+	}
+
+	sa = (struct sockaddr_storage *) (data + arg->field.field->offset);
+
+	if (sa->ss_family == AF_INET) {
+		struct sockaddr_in *sa4 = (struct sockaddr_in *) sa;
+
+		if (arg->field.field->size < sizeof(struct sockaddr_in)) {
+			trace_seq_printf(s, "INVALIDIPv4");
+			return rc;
+		}
+
+		print_ip4_addr(s, i, (unsigned char *) &sa4->sin_addr);
+		if (have_p)
+			trace_seq_printf(s, ":%d", ntohs(sa4->sin_port));
+
+
+	} else if (sa->ss_family == AF_INET6) {
+		struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) sa;
+
+		if (arg->field.field->size < sizeof(struct sockaddr_in6)) {
+			trace_seq_printf(s, "INVALIDIPv6");
+			return rc;
+		}
+
+		if (have_p)
+			trace_seq_printf(s, "[");
+
+		buf = (unsigned char *) &sa6->sin6_addr;
+		if (have_c)
+			print_ip6c_addr(s, buf);
+		else
+			print_ip6_addr(s, i, buf);
+
+		if (have_p)
+			trace_seq_printf(s, "]:%d", ntohs(sa6->sin6_port));
+	}
+
+	return rc;
+}
+
+static int print_ip_arg(struct trace_seq *s, const char *ptr,
+			void *data, int size, struct event_format *event,
+			struct print_arg *arg)
+{
+	char i = *ptr;  /* 'i' or 'I' */
+	char ver;
+	int rc = 0;
+
+	ptr++;
+	rc++;
+
+	ver = *ptr;
+	ptr++;
+	rc++;
+
+	switch (ver) {
+	case '4':
+		rc += print_ipv4_arg(s, ptr, i, data, size, event, arg);
+		break;
+	case '6':
+		rc += print_ipv6_arg(s, ptr, i, data, size, event, arg);
+		break;
+	case 'S':
+		rc += print_ipsa_arg(s, ptr, i, data, size, event, arg);
+		break;
+	default:
+		return 0;
+	}
+
+	return rc;
+}
+
+static int is_printable_array(char *p, unsigned int len)
+{
+	unsigned int i;
+
+	for (i = 0; i < len && p[i]; i++)
+		if (!isprint(p[i]) && !isspace(p[i]))
+		    return 0;
+	return 1;
+}
+
+static void print_event_fields(struct trace_seq *s, void *data,
+			       int size __maybe_unused,
+			       struct event_format *event)
+{
+	struct format_field *field;
+	unsigned long long val;
+	unsigned int offset, len, i;
+
+	field = event->format.fields;
+	while (field) {
+		trace_seq_printf(s, " %s=", field->name);
+		if (field->flags & FIELD_IS_ARRAY) {
+			offset = field->offset;
+			len = field->size;
+			if (field->flags & FIELD_IS_DYNAMIC) {
+				val = pevent_read_number(event->pevent, data + offset, len);
+				offset = val;
+				len = offset >> 16;
+				offset &= 0xffff;
+			}
+			if (field->flags & FIELD_IS_STRING &&
+			    is_printable_array(data + offset, len)) {
+				trace_seq_printf(s, "%s", (char *)data + offset);
+			} else {
+				trace_seq_puts(s, "ARRAY[");
+				for (i = 0; i < len; i++) {
+					if (i)
+						trace_seq_puts(s, ", ");
+					trace_seq_printf(s, "%02x",
+							 *((unsigned char *)data + offset + i));
+				}
+				trace_seq_putc(s, ']');
+				field->flags &= ~FIELD_IS_STRING;
+			}
+		} else {
+			val = pevent_read_number(event->pevent, data + field->offset,
+						 field->size);
+			if (field->flags & FIELD_IS_POINTER) {
+				trace_seq_printf(s, "0x%llx", val);
+			} else if (field->flags & FIELD_IS_SIGNED) {
+				switch (field->size) {
+				case 4:
+					/*
+					 * If field is long then print it in hex.
+					 * A long usually stores pointers.
+					 */
+					if (field->flags & FIELD_IS_LONG)
+						trace_seq_printf(s, "0x%x", (int)val);
+					else
+						trace_seq_printf(s, "%d", (int)val);
+					break;
+				case 2:
+					trace_seq_printf(s, "%2d", (short)val);
+					break;
+				case 1:
+					trace_seq_printf(s, "%1d", (char)val);
+					break;
+				default:
+					trace_seq_printf(s, "%lld", val);
+				}
+			} else {
+				if (field->flags & FIELD_IS_LONG)
+					trace_seq_printf(s, "0x%llx", val);
+				else
+					trace_seq_printf(s, "%llu", val);
+			}
+		}
+		field = field->next;
+	}
+}
+
+static void pretty_print(struct trace_seq *s, void *data, int size, struct event_format *event)
+{
+	struct pevent *pevent = event->pevent;
+	struct print_fmt *print_fmt = &event->print_fmt;
+	struct print_arg *arg = print_fmt->args;
+	struct print_arg *args = NULL;
+	const char *ptr = print_fmt->format;
+	unsigned long long val;
+	struct func_map *func;
+	const char *saveptr;
+	struct trace_seq p;
+	char *bprint_fmt = NULL;
+	char format[32];
+	int show_func;
+	int len_as_arg;
+	int len_arg;
+	int len;
+	int ls;
+
+	if (event->flags & EVENT_FL_FAILED) {
+		trace_seq_printf(s, "[FAILED TO PARSE]");
+		print_event_fields(s, data, size, event);
+		return;
+	}
+
+	if (event->flags & EVENT_FL_ISBPRINT) {
+		bprint_fmt = get_bprint_format(data, size, event);
+		args = make_bprint_args(bprint_fmt, data, size, event);
+		arg = args;
+		ptr = bprint_fmt;
+	}
+
+	for (; *ptr; ptr++) {
+		ls = 0;
+		if (*ptr == '\\') {
+			ptr++;
+			switch (*ptr) {
+			case 'n':
+				trace_seq_putc(s, '\n');
+				break;
+			case 't':
+				trace_seq_putc(s, '\t');
+				break;
+			case 'r':
+				trace_seq_putc(s, '\r');
+				break;
+			case '\\':
+				trace_seq_putc(s, '\\');
+				break;
+			default:
+				trace_seq_putc(s, *ptr);
+				break;
+			}
+
+		} else if (*ptr == '%') {
+			saveptr = ptr;
+			show_func = 0;
+			len_as_arg = 0;
+ cont_process:
+			ptr++;
+			switch (*ptr) {
+			case '%':
+				trace_seq_putc(s, '%');
+				break;
+			case '#':
+				/* FIXME: need to handle properly */
+				goto cont_process;
+			case 'h':
+				ls--;
+				goto cont_process;
+			case 'l':
+				ls++;
+				goto cont_process;
+			case 'L':
+				ls = 2;
+				goto cont_process;
+			case '*':
+				/* The argument is the length. */
+				if (!arg) {
+					do_warning_event(event, "no argument match");
+					event->flags |= EVENT_FL_FAILED;
+					goto out_failed;
+				}
+				len_arg = eval_num_arg(data, size, event, arg);
+				len_as_arg = 1;
+				arg = arg->next;
+				goto cont_process;
+			case '.':
+			case 'z':
+			case 'Z':
+			case '0' ... '9':
+				goto cont_process;
+			case 'p':
+				if (pevent->long_size == 4)
+					ls = 1;
+				else
+					ls = 2;
+
+				if (*(ptr+1) == 'F' ||
+				    *(ptr+1) == 'f') {
+					ptr++;
+					show_func = *ptr;
+				} else if (*(ptr+1) == 'M' || *(ptr+1) == 'm') {
+					print_mac_arg(s, *(ptr+1), data, size, event, arg);
+					ptr++;
+					arg = arg->next;
+					break;
+				} else if (*(ptr+1) == 'I' || *(ptr+1) == 'i') {
+					int n;
+
+					n = print_ip_arg(s, ptr+1, data, size, event, arg);
+					if (n > 0) {
+						ptr += n;
+						arg = arg->next;
+						break;
+					}
+				}
+
+				/* fall through */
+			case 'd':
+			case 'i':
+			case 'x':
+			case 'X':
+			case 'u':
+				if (!arg) {
+					do_warning_event(event, "no argument match");
+					event->flags |= EVENT_FL_FAILED;
+					goto out_failed;
+				}
+
+				len = ((unsigned long)ptr + 1) -
+					(unsigned long)saveptr;
+
+				/* should never happen */
+				if (len > 31) {
+					do_warning_event(event, "bad format!");
+					event->flags |= EVENT_FL_FAILED;
+					len = 31;
+				}
+
+				memcpy(format, saveptr, len);
+				format[len] = 0;
+
+				val = eval_num_arg(data, size, event, arg);
+				arg = arg->next;
+
+				if (show_func) {
+					func = find_func(pevent, val);
+					if (func) {
+						trace_seq_puts(s, func->func);
+						if (show_func == 'F')
+							trace_seq_printf(s,
+							       "+0x%llx",
+							       val - func->addr);
+						break;
+					}
+				}
+				if (pevent->long_size == 8 && ls &&
+				    sizeof(long) != 8) {
+					char *p;
+
+					ls = 2;
+					/* make %l into %ll */
+					p = strchr(format, 'l');
+					if (p)
+						memmove(p+1, p, strlen(p)+1);
+					else if (strcmp(format, "%p") == 0)
+						strcpy(format, "0x%llx");
+				}
+				switch (ls) {
+				case -2:
+					if (len_as_arg)
+						trace_seq_printf(s, format, len_arg, (char)val);
+					else
+						trace_seq_printf(s, format, (char)val);
+					break;
+				case -1:
+					if (len_as_arg)
+						trace_seq_printf(s, format, len_arg, (short)val);
+					else
+						trace_seq_printf(s, format, (short)val);
+					break;
+				case 0:
+					if (len_as_arg)
+						trace_seq_printf(s, format, len_arg, (int)val);
+					else
+						trace_seq_printf(s, format, (int)val);
+					break;
+				case 1:
+					if (len_as_arg)
+						trace_seq_printf(s, format, len_arg, (long)val);
+					else
+						trace_seq_printf(s, format, (long)val);
+					break;
+				case 2:
+					if (len_as_arg)
+						trace_seq_printf(s, format, len_arg,
+								 (long long)val);
+					else
+						trace_seq_printf(s, format, (long long)val);
+					break;
+				default:
+					do_warning_event(event, "bad count (%d)", ls);
+					event->flags |= EVENT_FL_FAILED;
+				}
+				break;
+			case 's':
+				if (!arg) {
+					do_warning_event(event, "no matching argument");
+					event->flags |= EVENT_FL_FAILED;
+					goto out_failed;
+				}
+
+				len = ((unsigned long)ptr + 1) -
+					(unsigned long)saveptr;
+
+				/* should never happen */
+				if (len > 31) {
+					do_warning_event(event, "bad format!");
+					event->flags |= EVENT_FL_FAILED;
+					len = 31;
+				}
+
+				memcpy(format, saveptr, len);
+				format[len] = 0;
+				if (!len_as_arg)
+					len_arg = -1;
+				/* Use helper trace_seq */
+				trace_seq_init(&p);
+				print_str_arg(&p, data, size, event,
+					      format, len_arg, arg);
+				trace_seq_terminate(&p);
+				trace_seq_puts(s, p.buffer);
+				trace_seq_destroy(&p);
+				arg = arg->next;
+				break;
+			default:
+				trace_seq_printf(s, ">%c<", *ptr);
+
+			}
+		} else
+			trace_seq_putc(s, *ptr);
+	}
+
+	if (event->flags & EVENT_FL_FAILED) {
+out_failed:
+		trace_seq_printf(s, "[FAILED TO PARSE]");
+	}
+
+	if (args) {
+		free_args(args);
+		free(bprint_fmt);
+	}
+}
+
+/**
+ * pevent_data_lat_fmt - parse the data for the latency format
+ * @pevent: a handle to the pevent
+ * @s: the trace_seq to write to
+ * @record: the record to read from
+ *
+ * This parses out the Latency format (interrupts disabled,
+ * need rescheduling, in hard/soft interrupt, preempt count
+ * and lock depth) and places it into the trace_seq.
+ */
+void pevent_data_lat_fmt(struct pevent *pevent,
+			 struct trace_seq *s, struct pevent_record *record)
+{
+	static int check_lock_depth = 1;
+	static int check_migrate_disable = 1;
+	static int lock_depth_exists;
+	static int migrate_disable_exists;
+	unsigned int lat_flags;
+	unsigned int pc;
+	int lock_depth;
+	int migrate_disable;
+	int hardirq;
+	int softirq;
+	void *data = record->data;
+
+	lat_flags = parse_common_flags(pevent, data);
+	pc = parse_common_pc(pevent, data);
+	/* lock_depth may not always exist */
+	if (lock_depth_exists)
+		lock_depth = parse_common_lock_depth(pevent, data);
+	else if (check_lock_depth) {
+		lock_depth = parse_common_lock_depth(pevent, data);
+		if (lock_depth < 0)
+			check_lock_depth = 0;
+		else
+			lock_depth_exists = 1;
+	}
+
+	/* migrate_disable may not always exist */
+	if (migrate_disable_exists)
+		migrate_disable = parse_common_migrate_disable(pevent, data);
+	else if (check_migrate_disable) {
+		migrate_disable = parse_common_migrate_disable(pevent, data);
+		if (migrate_disable < 0)
+			check_migrate_disable = 0;
+		else
+			migrate_disable_exists = 1;
+	}
+
+	hardirq = lat_flags & TRACE_FLAG_HARDIRQ;
+	softirq = lat_flags & TRACE_FLAG_SOFTIRQ;
+
+	trace_seq_printf(s, "%c%c%c",
+	       (lat_flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
+	       (lat_flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
+	       'X' : '.',
+	       (lat_flags & TRACE_FLAG_NEED_RESCHED) ?
+	       'N' : '.',
+	       (hardirq && softirq) ? 'H' :
+	       hardirq ? 'h' : softirq ? 's' : '.');
+
+	if (pc)
+		trace_seq_printf(s, "%x", pc);
+	else
+		trace_seq_putc(s, '.');
+
+	if (migrate_disable_exists) {
+		if (migrate_disable < 0)
+			trace_seq_putc(s, '.');
+		else
+			trace_seq_printf(s, "%d", migrate_disable);
+	}
+
+	if (lock_depth_exists) {
+		if (lock_depth < 0)
+			trace_seq_putc(s, '.');
+		else
+			trace_seq_printf(s, "%d", lock_depth);
+	}
+
+	trace_seq_terminate(s);
+}
+
+/**
+ * pevent_data_type - parse out the given event type
+ * @pevent: a handle to the pevent
+ * @rec: the record to read from
+ *
+ * This returns the event id from the @rec.
+ */
+int pevent_data_type(struct pevent *pevent, struct pevent_record *rec)
+{
+	return trace_parse_common_type(pevent, rec->data);
+}
+
+/**
+ * pevent_data_event_from_type - find the event by a given type
+ * @pevent: a handle to the pevent
+ * @type: the type of the event.
+ *
+ * This returns the event form a given @type;
+ */
+struct event_format *pevent_data_event_from_type(struct pevent *pevent, int type)
+{
+	return pevent_find_event(pevent, type);
+}
+
+/**
+ * pevent_data_pid - parse the PID from raw data
+ * @pevent: a handle to the pevent
+ * @rec: the record to parse
+ *
+ * This returns the PID from a raw data.
+ */
+int pevent_data_pid(struct pevent *pevent, struct pevent_record *rec)
+{
+	return parse_common_pid(pevent, rec->data);
+}
+
+/**
+ * pevent_data_comm_from_pid - return the command line from PID
+ * @pevent: a handle to the pevent
+ * @pid: the PID of the task to search for
+ *
+ * This returns a pointer to the command line that has the given
+ * @pid.
+ */
+const char *pevent_data_comm_from_pid(struct pevent *pevent, int pid)
+{
+	const char *comm;
+
+	comm = find_cmdline(pevent, pid);
+	return comm;
+}
+
+static struct cmdline *
+pid_from_cmdlist(struct pevent *pevent, const char *comm, struct cmdline *next)
+{
+	struct cmdline_list *cmdlist = (struct cmdline_list *)next;
+
+	if (cmdlist)
+		cmdlist = cmdlist->next;
+	else
+		cmdlist = pevent->cmdlist;
+
+	while (cmdlist && strcmp(cmdlist->comm, comm) != 0)
+		cmdlist = cmdlist->next;
+
+	return (struct cmdline *)cmdlist;
+}
+
+/**
+ * pevent_data_pid_from_comm - return the pid from a given comm
+ * @pevent: a handle to the pevent
+ * @comm: the cmdline to find the pid from
+ * @next: the cmdline structure to find the next comm
+ *
+ * This returns the cmdline structure that holds a pid for a given
+ * comm, or NULL if none found. As there may be more than one pid for
+ * a given comm, the result of this call can be passed back into
+ * a recurring call in the @next paramater, and then it will find the
+ * next pid.
+ * Also, it does a linear seach, so it may be slow.
+ */
+struct cmdline *pevent_data_pid_from_comm(struct pevent *pevent, const char *comm,
+					  struct cmdline *next)
+{
+	struct cmdline *cmdline;
+
+	/*
+	 * If the cmdlines have not been converted yet, then use
+	 * the list.
+	 */
+	if (!pevent->cmdlines)
+		return pid_from_cmdlist(pevent, comm, next);
+
+	if (next) {
+		/*
+		 * The next pointer could have been still from
+		 * a previous call before cmdlines were created
+		 */
+		if (next < pevent->cmdlines ||
+		    next >= pevent->cmdlines + pevent->cmdline_count)
+			next = NULL;
+		else
+			cmdline  = next++;
+	}
+
+	if (!next)
+		cmdline = pevent->cmdlines;
+
+	while (cmdline < pevent->cmdlines + pevent->cmdline_count) {
+		if (strcmp(cmdline->comm, comm) == 0)
+			return cmdline;
+		cmdline++;
+	}
+	return NULL;
+}
+
+/**
+ * pevent_cmdline_pid - return the pid associated to a given cmdline
+ * @cmdline: The cmdline structure to get the pid from
+ *
+ * Returns the pid for a give cmdline. If @cmdline is NULL, then
+ * -1 is returned.
+ */
+int pevent_cmdline_pid(struct pevent *pevent, struct cmdline *cmdline)
+{
+	struct cmdline_list *cmdlist = (struct cmdline_list *)cmdline;
+
+	if (!cmdline)
+		return -1;
+
+	/*
+	 * If cmdlines have not been created yet, or cmdline is
+	 * not part of the array, then treat it as a cmdlist instead.
+	 */
+	if (!pevent->cmdlines ||
+	    cmdline < pevent->cmdlines ||
+	    cmdline >= pevent->cmdlines + pevent->cmdline_count)
+		return cmdlist->pid;
+
+	return cmdline->pid;
+}
+
+/**
+ * pevent_data_comm_from_pid - parse the data into the print format
+ * @s: the trace_seq to write to
+ * @event: the handle to the event
+ * @record: the record to read from
+ *
+ * This parses the raw @data using the given @event information and
+ * writes the print format into the trace_seq.
+ */
+void pevent_event_info(struct trace_seq *s, struct event_format *event,
+		       struct pevent_record *record)
+{
+	int print_pretty = 1;
+
+	if (event->pevent->print_raw || (event->flags & EVENT_FL_PRINTRAW))
+		print_event_fields(s, record->data, record->size, event);
+	else {
+
+		if (event->handler && !(event->flags & EVENT_FL_NOHANDLE))
+			print_pretty = event->handler(s, record, event,
+						      event->context);
+
+		if (print_pretty)
+			pretty_print(s, record->data, record->size, event);
+	}
+
+	trace_seq_terminate(s);
+}
+
+static bool is_timestamp_in_us(char *trace_clock, bool use_trace_clock)
+{
+	if (!use_trace_clock)
+		return true;
+
+	if (!strcmp(trace_clock, "local") || !strcmp(trace_clock, "global")
+	    || !strcmp(trace_clock, "uptime") || !strcmp(trace_clock, "perf"))
+		return true;
+
+	/* trace_clock is setting in tsc or counter mode */
+	return false;
+}
+
+void pevent_print_event(struct pevent *pevent, struct trace_seq *s,
+			struct pevent_record *record, bool use_trace_clock)
+{
+	static const char *spaces = "                    "; /* 20 spaces */
+	struct event_format *event;
+	unsigned long secs;
+	unsigned long usecs;
+	unsigned long nsecs;
+	const char *comm;
+	void *data = record->data;
+	int type;
+	int pid;
+	int len;
+	int p;
+	bool use_usec_format;
+
+	use_usec_format = is_timestamp_in_us(pevent->trace_clock,
+							use_trace_clock);
+	if (use_usec_format) {
+		secs = record->ts / NSECS_PER_SEC;
+		nsecs = record->ts - secs * NSECS_PER_SEC;
+	}
+
+	if (record->size < 0) {
+		do_warning("ug! negative record size %d", record->size);
+		return;
+	}
+
+	type = trace_parse_common_type(pevent, data);
+
+	event = pevent_find_event(pevent, type);
+	if (!event) {
+		do_warning("ug! no event found for type %d", type);
+		return;
+	}
+
+	pid = parse_common_pid(pevent, data);
+	comm = find_cmdline(pevent, pid);
+
+	if (pevent->latency_format) {
+		trace_seq_printf(s, "%8.8s-%-5d %3d",
+		       comm, pid, record->cpu);
+		pevent_data_lat_fmt(pevent, s, record);
+	} else
+		trace_seq_printf(s, "%16s-%-5d [%03d]", comm, pid, record->cpu);
+
+	if (use_usec_format) {
+		if (pevent->flags & PEVENT_NSEC_OUTPUT) {
+			usecs = nsecs;
+			p = 9;
+		} else {
+			usecs = (nsecs + 500) / NSECS_PER_USEC;
+			p = 6;
+		}
+
+		trace_seq_printf(s, " %5lu.%0*lu: %s: ",
+					secs, p, usecs, event->name);
+	} else
+		trace_seq_printf(s, " %12llu: %s: ",
+					record->ts, event->name);
+
+	/* Space out the event names evenly. */
+	len = strlen(event->name);
+	if (len < 20)
+		trace_seq_printf(s, "%.*s", 20 - len, spaces);
+
+	pevent_event_info(s, event, record);
+}
+
+static int events_id_cmp(const void *a, const void *b)
+{
+	struct event_format * const * ea = a;
+	struct event_format * const * eb = b;
+
+	if ((*ea)->id < (*eb)->id)
+		return -1;
+
+	if ((*ea)->id > (*eb)->id)
+		return 1;
+
+	return 0;
+}
+
+static int events_name_cmp(const void *a, const void *b)
+{
+	struct event_format * const * ea = a;
+	struct event_format * const * eb = b;
+	int res;
+
+	res = strcmp((*ea)->name, (*eb)->name);
+	if (res)
+		return res;
+
+	res = strcmp((*ea)->system, (*eb)->system);
+	if (res)
+		return res;
+
+	return events_id_cmp(a, b);
+}
+
+static int events_system_cmp(const void *a, const void *b)
+{
+	struct event_format * const * ea = a;
+	struct event_format * const * eb = b;
+	int res;
+
+	res = strcmp((*ea)->system, (*eb)->system);
+	if (res)
+		return res;
+
+	res = strcmp((*ea)->name, (*eb)->name);
+	if (res)
+		return res;
+
+	return events_id_cmp(a, b);
+}
+
+struct event_format **pevent_list_events(struct pevent *pevent, enum event_sort_type sort_type)
+{
+	struct event_format **events;
+	int (*sort)(const void *a, const void *b);
+
+	events = pevent->sort_events;
+
+	if (events && pevent->last_type == sort_type)
+		return events;
+
+	if (!events) {
+		events = malloc(sizeof(*events) * (pevent->nr_events + 1));
+		if (!events)
+			return NULL;
+
+		memcpy(events, pevent->events, sizeof(*events) * pevent->nr_events);
+		events[pevent->nr_events] = NULL;
+
+		pevent->sort_events = events;
+
+		/* the internal events are sorted by id */
+		if (sort_type == EVENT_SORT_ID) {
+			pevent->last_type = sort_type;
+			return events;
+		}
+	}
+
+	switch (sort_type) {
+	case EVENT_SORT_ID:
+		sort = events_id_cmp;
+		break;
+	case EVENT_SORT_NAME:
+		sort = events_name_cmp;
+		break;
+	case EVENT_SORT_SYSTEM:
+		sort = events_system_cmp;
+		break;
+	default:
+		return events;
+	}
+
+	qsort(events, pevent->nr_events, sizeof(*events), sort);
+	pevent->last_type = sort_type;
+
+	return events;
+}
+
+static struct format_field **
+get_event_fields(const char *type, const char *name,
+		 int count, struct format_field *list)
+{
+	struct format_field **fields;
+	struct format_field *field;
+	int i = 0;
+
+	fields = malloc(sizeof(*fields) * (count + 1));
+	if (!fields)
+		return NULL;
+
+	for (field = list; field; field = field->next) {
+		fields[i++] = field;
+		if (i == count + 1) {
+			do_warning("event %s has more %s fields than specified",
+				name, type);
+			i--;
+			break;
+		}
+	}
+
+	if (i != count)
+		do_warning("event %s has less %s fields than specified",
+			name, type);
+
+	fields[i] = NULL;
+
+	return fields;
+}
+
+/**
+ * pevent_event_common_fields - return a list of common fields for an event
+ * @event: the event to return the common fields of.
+ *
+ * Returns an allocated array of fields. The last item in the array is NULL.
+ * The array must be freed with free().
+ */
+struct format_field **pevent_event_common_fields(struct event_format *event)
+{
+	return get_event_fields("common", event->name,
+				event->format.nr_common,
+				event->format.common_fields);
+}
+
+/**
+ * pevent_event_fields - return a list of event specific fields for an event
+ * @event: the event to return the fields of.
+ *
+ * Returns an allocated array of fields. The last item in the array is NULL.
+ * The array must be freed with free().
+ */
+struct format_field **pevent_event_fields(struct event_format *event)
+{
+	return get_event_fields("event", event->name,
+				event->format.nr_fields,
+				event->format.fields);
+}
+
+static void print_fields(struct trace_seq *s, struct print_flag_sym *field)
+{
+	trace_seq_printf(s, "{ %s, %s }", field->value, field->str);
+	if (field->next) {
+		trace_seq_puts(s, ", ");
+		print_fields(s, field->next);
+	}
+}
+
+/* for debugging */
+static void print_args(struct print_arg *args)
+{
+	int print_paren = 1;
+	struct trace_seq s;
+
+	switch (args->type) {
+	case PRINT_NULL:
+		printf("null");
+		break;
+	case PRINT_ATOM:
+		printf("%s", args->atom.atom);
+		break;
+	case PRINT_FIELD:
+		printf("REC->%s", args->field.name);
+		break;
+	case PRINT_FLAGS:
+		printf("__print_flags(");
+		print_args(args->flags.field);
+		printf(", %s, ", args->flags.delim);
+		trace_seq_init(&s);
+		print_fields(&s, args->flags.flags);
+		trace_seq_do_printf(&s);
+		trace_seq_destroy(&s);
+		printf(")");
+		break;
+	case PRINT_SYMBOL:
+		printf("__print_symbolic(");
+		print_args(args->symbol.field);
+		printf(", ");
+		trace_seq_init(&s);
+		print_fields(&s, args->symbol.symbols);
+		trace_seq_do_printf(&s);
+		trace_seq_destroy(&s);
+		printf(")");
+		break;
+	case PRINT_HEX:
+		printf("__print_hex(");
+		print_args(args->hex.field);
+		printf(", ");
+		print_args(args->hex.size);
+		printf(")");
+		break;
+	case PRINT_INT_ARRAY:
+		printf("__print_array(");
+		print_args(args->int_array.field);
+		printf(", ");
+		print_args(args->int_array.count);
+		printf(", ");
+		print_args(args->int_array.el_size);
+		printf(")");
+		break;
+	case PRINT_STRING:
+	case PRINT_BSTRING:
+		printf("__get_str(%s)", args->string.string);
+		break;
+	case PRINT_BITMASK:
+		printf("__get_bitmask(%s)", args->bitmask.bitmask);
+		break;
+	case PRINT_TYPE:
+		printf("(%s)", args->typecast.type);
+		print_args(args->typecast.item);
+		break;
+	case PRINT_OP:
+		if (strcmp(args->op.op, ":") == 0)
+			print_paren = 0;
+		if (print_paren)
+			printf("(");
+		print_args(args->op.left);
+		printf(" %s ", args->op.op);
+		print_args(args->op.right);
+		if (print_paren)
+			printf(")");
+		break;
+	default:
+		/* we should warn... */
+		return;
+	}
+	if (args->next) {
+		printf("\n");
+		print_args(args->next);
+	}
+}
+
+static void parse_header_field(const char *field,
+			       int *offset, int *size, int mandatory)
+{
+	unsigned long long save_input_buf_ptr;
+	unsigned long long save_input_buf_siz;
+	char *token;
+	int type;
+
+	save_input_buf_ptr = input_buf_ptr;
+	save_input_buf_siz = input_buf_siz;
+
+	if (read_expected(EVENT_ITEM, "field") < 0)
+		return;
+	if (read_expected(EVENT_OP, ":") < 0)
+		return;
+
+	/* type */
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+	free_token(token);
+
+	/*
+	 * If this is not a mandatory field, then test it first.
+	 */
+	if (mandatory) {
+		if (read_expected(EVENT_ITEM, field) < 0)
+			return;
+	} else {
+		if (read_expect_type(EVENT_ITEM, &token) < 0)
+			goto fail;
+		if (strcmp(token, field) != 0)
+			goto discard;
+		free_token(token);
+	}
+
+	if (read_expected(EVENT_OP, ";") < 0)
+		return;
+	if (read_expected(EVENT_ITEM, "offset") < 0)
+		return;
+	if (read_expected(EVENT_OP, ":") < 0)
+		return;
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+	*offset = atoi(token);
+	free_token(token);
+	if (read_expected(EVENT_OP, ";") < 0)
+		return;
+	if (read_expected(EVENT_ITEM, "size") < 0)
+		return;
+	if (read_expected(EVENT_OP, ":") < 0)
+		return;
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+	*size = atoi(token);
+	free_token(token);
+	if (read_expected(EVENT_OP, ";") < 0)
+		return;
+	type = read_token(&token);
+	if (type != EVENT_NEWLINE) {
+		/* newer versions of the kernel have a "signed" type */
+		if (type != EVENT_ITEM)
+			goto fail;
+
+		if (strcmp(token, "signed") != 0)
+			goto fail;
+
+		free_token(token);
+
+		if (read_expected(EVENT_OP, ":") < 0)
+			return;
+
+		if (read_expect_type(EVENT_ITEM, &token))
+			goto fail;
+
+		free_token(token);
+		if (read_expected(EVENT_OP, ";") < 0)
+			return;
+
+		if (read_expect_type(EVENT_NEWLINE, &token))
+			goto fail;
+	}
+ fail:
+	free_token(token);
+	return;
+
+ discard:
+	input_buf_ptr = save_input_buf_ptr;
+	input_buf_siz = save_input_buf_siz;
+	*offset = 0;
+	*size = 0;
+	free_token(token);
+}
+
+/**
+ * pevent_parse_header_page - parse the data stored in the header page
+ * @pevent: the handle to the pevent
+ * @buf: the buffer storing the header page format string
+ * @size: the size of @buf
+ * @long_size: the long size to use if there is no header
+ *
+ * This parses the header page format for information on the
+ * ring buffer used. The @buf should be copied from
+ *
+ * /sys/kernel/debug/tracing/events/header_page
+ */
+int pevent_parse_header_page(struct pevent *pevent, char *buf, unsigned long size,
+			     int long_size)
+{
+	int ignore;
+
+	if (!size) {
+		/*
+		 * Old kernels did not have header page info.
+		 * Sorry but we just use what we find here in user space.
+		 */
+		pevent->header_page_ts_size = sizeof(long long);
+		pevent->header_page_size_size = long_size;
+		pevent->header_page_data_offset = sizeof(long long) + long_size;
+		pevent->old_format = 1;
+		return -1;
+	}
+	init_input_buf(buf, size);
+
+	parse_header_field("timestamp", &pevent->header_page_ts_offset,
+			   &pevent->header_page_ts_size, 1);
+	parse_header_field("commit", &pevent->header_page_size_offset,
+			   &pevent->header_page_size_size, 1);
+	parse_header_field("overwrite", &pevent->header_page_overwrite,
+			   &ignore, 0);
+	parse_header_field("data", &pevent->header_page_data_offset,
+			   &pevent->header_page_data_size, 1);
+
+	return 0;
+}
+
+static int event_matches(struct event_format *event,
+			 int id, const char *sys_name,
+			 const char *event_name)
+{
+	if (id >= 0 && id != event->id)
+		return 0;
+
+	if (event_name && (strcmp(event_name, event->name) != 0))
+		return 0;
+
+	if (sys_name && (strcmp(sys_name, event->system) != 0))
+		return 0;
+
+	return 1;
+}
+
+static void free_handler(struct event_handler *handle)
+{
+	free((void *)handle->sys_name);
+	free((void *)handle->event_name);
+	free(handle);
+}
+
+static int find_event_handle(struct pevent *pevent, struct event_format *event)
+{
+	struct event_handler *handle, **next;
+
+	for (next = &pevent->handlers; *next;
+	     next = &(*next)->next) {
+		handle = *next;
+		if (event_matches(event, handle->id,
+				  handle->sys_name,
+				  handle->event_name))
+			break;
+	}
+
+	if (!(*next))
+		return 0;
+
+	pr_stat("overriding event (%d) %s:%s with new print handler",
+		event->id, event->system, event->name);
+
+	event->handler = handle->func;
+	event->context = handle->context;
+
+	*next = handle->next;
+	free_handler(handle);
+
+	return 1;
+}
+
+/**
+ * __pevent_parse_format - parse the event format
+ * @buf: the buffer storing the event format string
+ * @size: the size of @buf
+ * @sys: the system the event belongs to
+ *
+ * This parses the event format and creates an event structure
+ * to quickly parse raw data for a given event.
+ *
+ * These files currently come from:
+ *
+ * /sys/kernel/debug/tracing/events/.../.../format
+ */
+enum pevent_errno __pevent_parse_format(struct event_format **eventp,
+					struct pevent *pevent, const char *buf,
+					unsigned long size, const char *sys)
+{
+	struct event_format *event;
+	int ret;
+
+	init_input_buf(buf, size);
+
+	*eventp = event = alloc_event();
+	if (!event)
+		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+
+	event->name = event_read_name();
+	if (!event->name) {
+		/* Bad event? */
+		ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
+		goto event_alloc_failed;
+	}
+
+	if (strcmp(sys, "ftrace") == 0) {
+		event->flags |= EVENT_FL_ISFTRACE;
+
+		if (strcmp(event->name, "bprint") == 0)
+			event->flags |= EVENT_FL_ISBPRINT;
+	}
+		
+	event->id = event_read_id();
+	if (event->id < 0) {
+		ret = PEVENT_ERRNO__READ_ID_FAILED;
+		/*
+		 * This isn't an allocation error actually.
+		 * But as the ID is critical, just bail out.
+		 */
+		goto event_alloc_failed;
+	}
+
+	event->system = strdup(sys);
+	if (!event->system) {
+		ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
+		goto event_alloc_failed;
+	}
+
+	/* Add pevent to event so that it can be referenced */
+	event->pevent = pevent;
+
+	ret = event_read_format(event);
+	if (ret < 0) {
+		ret = PEVENT_ERRNO__READ_FORMAT_FAILED;
+		goto event_parse_failed;
+	}
+
+	/*
+	 * If the event has an override, don't print warnings if the event
+	 * print format fails to parse.
+	 */
+	if (pevent && find_event_handle(pevent, event))
+		show_warning = 0;
+
+	ret = event_read_print(event);
+	show_warning = 1;
+
+	if (ret < 0) {
+		ret = PEVENT_ERRNO__READ_PRINT_FAILED;
+		goto event_parse_failed;
+	}
+
+	if (!ret && (event->flags & EVENT_FL_ISFTRACE)) {
+		struct format_field *field;
+		struct print_arg *arg, **list;
+
+		/* old ftrace had no args */
+		list = &event->print_fmt.args;
+		for (field = event->format.fields; field; field = field->next) {
+			arg = alloc_arg();
+			if (!arg) {
+				event->flags |= EVENT_FL_FAILED;
+				return PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED;
+			}
+			arg->type = PRINT_FIELD;
+			arg->field.name = strdup(field->name);
+			if (!arg->field.name) {
+				event->flags |= EVENT_FL_FAILED;
+				free_arg(arg);
+				return PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED;
+			}
+			arg->field.field = field;
+			*list = arg;
+			list = &arg->next;
+		}
+		return 0;
+	}
+
+	return 0;
+
+ event_parse_failed:
+	event->flags |= EVENT_FL_FAILED;
+	return ret;
+
+ event_alloc_failed:
+	free(event->system);
+	free(event->name);
+	free(event);
+	*eventp = NULL;
+	return ret;
+}
+
+static enum pevent_errno
+__pevent_parse_event(struct pevent *pevent,
+		     struct event_format **eventp,
+		     const char *buf, unsigned long size,
+		     const char *sys)
+{
+	int ret = __pevent_parse_format(eventp, pevent, buf, size, sys);
+	struct event_format *event = *eventp;
+
+	if (event == NULL)
+		return ret;
+
+	if (pevent && add_event(pevent, event)) {
+		ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
+		goto event_add_failed;
+	}
+
+#define PRINT_ARGS 0
+	if (PRINT_ARGS && event->print_fmt.args)
+		print_args(event->print_fmt.args);
+
+	return 0;
+
+event_add_failed:
+	pevent_free_format(event);
+	return ret;
+}
+
+/**
+ * pevent_parse_format - parse the event format
+ * @pevent: the handle to the pevent
+ * @eventp: returned format
+ * @buf: the buffer storing the event format string
+ * @size: the size of @buf
+ * @sys: the system the event belongs to
+ *
+ * This parses the event format and creates an event structure
+ * to quickly parse raw data for a given event.
+ *
+ * These files currently come from:
+ *
+ * /sys/kernel/debug/tracing/events/.../.../format
+ */
+enum pevent_errno pevent_parse_format(struct pevent *pevent,
+				      struct event_format **eventp,
+				      const char *buf,
+				      unsigned long size, const char *sys)
+{
+	return __pevent_parse_event(pevent, eventp, buf, size, sys);
+}
+
+/**
+ * pevent_parse_event - parse the event format
+ * @pevent: the handle to the pevent
+ * @buf: the buffer storing the event format string
+ * @size: the size of @buf
+ * @sys: the system the event belongs to
+ *
+ * This parses the event format and creates an event structure
+ * to quickly parse raw data for a given event.
+ *
+ * These files currently come from:
+ *
+ * /sys/kernel/debug/tracing/events/.../.../format
+ */
+enum pevent_errno pevent_parse_event(struct pevent *pevent, const char *buf,
+				     unsigned long size, const char *sys)
+{
+	struct event_format *event = NULL;
+	return __pevent_parse_event(pevent, &event, buf, size, sys);
+}
+
+#undef _PE
+#define _PE(code, str) str
+static const char * const pevent_error_str[] = {
+	PEVENT_ERRORS
+};
+#undef _PE
+
+int pevent_strerror(struct pevent *pevent __maybe_unused,
+		    enum pevent_errno errnum, char *buf, size_t buflen)
+{
+	int idx;
+	const char *msg;
+
+	if (errnum >= 0) {
+		msg = strerror_r(errnum, buf, buflen);
+		if (msg != buf) {
+			size_t len = strlen(msg);
+			memcpy(buf, msg, min(buflen - 1, len));
+			*(buf + min(buflen - 1, len)) = '\0';
+		}
+		return 0;
+	}
+
+	if (errnum <= __PEVENT_ERRNO__START ||
+	    errnum >= __PEVENT_ERRNO__END)
+		return -1;
+
+	idx = errnum - __PEVENT_ERRNO__START - 1;
+	msg = pevent_error_str[idx];
+	snprintf(buf, buflen, "%s", msg);
+
+	return 0;
+}
+
+int get_field_val(struct trace_seq *s, struct format_field *field,
+		  const char *name, struct pevent_record *record,
+		  unsigned long long *val, int err)
+{
+	if (!field) {
+		if (err)
+			trace_seq_printf(s, "<CANT FIND FIELD %s>", name);
+		return -1;
+	}
+
+	if (pevent_read_number_field(field, record->data, val)) {
+		if (err)
+			trace_seq_printf(s, " %s=INVALID", name);
+		return -1;
+	}
+
+	return 0;
+}
+
+/**
+ * pevent_get_field_raw - return the raw pointer into the data field
+ * @s: The seq to print to on error
+ * @event: the event that the field is for
+ * @name: The name of the field
+ * @record: The record with the field name.
+ * @len: place to store the field length.
+ * @err: print default error if failed.
+ *
+ * Returns a pointer into record->data of the field and places
+ * the length of the field in @len.
+ *
+ * On failure, it returns NULL.
+ */
+void *pevent_get_field_raw(struct trace_seq *s, struct event_format *event,
+			   const char *name, struct pevent_record *record,
+			   int *len, int err)
+{
+	struct format_field *field;
+	void *data = record->data;
+	unsigned offset;
+	int dummy;
+
+	if (!event)
+		return NULL;
+
+	field = pevent_find_field(event, name);
+
+	if (!field) {
+		if (err)
+			trace_seq_printf(s, "<CANT FIND FIELD %s>", name);
+		return NULL;
+	}
+
+	/* Allow @len to be NULL */
+	if (!len)
+		len = &dummy;
+
+	offset = field->offset;
+	if (field->flags & FIELD_IS_DYNAMIC) {
+		offset = pevent_read_number(event->pevent,
+					    data + offset, field->size);
+		*len = offset >> 16;
+		offset &= 0xffff;
+	} else
+		*len = field->size;
+
+	return data + offset;
+}
+
+/**
+ * pevent_get_field_val - find a field and return its value
+ * @s: The seq to print to on error
+ * @event: the event that the field is for
+ * @name: The name of the field
+ * @record: The record with the field name.
+ * @val: place to store the value of the field.
+ * @err: print default error if failed.
+ *
+ * Returns 0 on success -1 on field not found.
+ */
+int pevent_get_field_val(struct trace_seq *s, struct event_format *event,
+			 const char *name, struct pevent_record *record,
+			 unsigned long long *val, int err)
+{
+	struct format_field *field;
+
+	if (!event)
+		return -1;
+
+	field = pevent_find_field(event, name);
+
+	return get_field_val(s, field, name, record, val, err);
+}
+
+/**
+ * pevent_get_common_field_val - find a common field and return its value
+ * @s: The seq to print to on error
+ * @event: the event that the field is for
+ * @name: The name of the field
+ * @record: The record with the field name.
+ * @val: place to store the value of the field.
+ * @err: print default error if failed.
+ *
+ * Returns 0 on success -1 on field not found.
+ */
+int pevent_get_common_field_val(struct trace_seq *s, struct event_format *event,
+				const char *name, struct pevent_record *record,
+				unsigned long long *val, int err)
+{
+	struct format_field *field;
+
+	if (!event)
+		return -1;
+
+	field = pevent_find_common_field(event, name);
+
+	return get_field_val(s, field, name, record, val, err);
+}
+
+/**
+ * pevent_get_any_field_val - find a any field and return its value
+ * @s: The seq to print to on error
+ * @event: the event that the field is for
+ * @name: The name of the field
+ * @record: The record with the field name.
+ * @val: place to store the value of the field.
+ * @err: print default error if failed.
+ *
+ * Returns 0 on success -1 on field not found.
+ */
+int pevent_get_any_field_val(struct trace_seq *s, struct event_format *event,
+			     const char *name, struct pevent_record *record,
+			     unsigned long long *val, int err)
+{
+	struct format_field *field;
+
+	if (!event)
+		return -1;
+
+	field = pevent_find_any_field(event, name);
+
+	return get_field_val(s, field, name, record, val, err);
+}
+
+/**
+ * pevent_print_num_field - print a field and a format
+ * @s: The seq to print to
+ * @fmt: The printf format to print the field with.
+ * @event: the event that the field is for
+ * @name: The name of the field
+ * @record: The record with the field name.
+ * @err: print default error if failed.
+ *
+ * Returns: 0 on success, -1 field not found, or 1 if buffer is full.
+ */
+int pevent_print_num_field(struct trace_seq *s, const char *fmt,
+			   struct event_format *event, const char *name,
+			   struct pevent_record *record, int err)
+{
+	struct format_field *field = pevent_find_field(event, name);
+	unsigned long long val;
+
+	if (!field)
+		goto failed;
+
+	if (pevent_read_number_field(field, record->data, &val))
+		goto failed;
+
+	return trace_seq_printf(s, fmt, val);
+
+ failed:
+	if (err)
+		trace_seq_printf(s, "CAN'T FIND FIELD \"%s\"", name);
+	return -1;
+}
+
+/**
+ * pevent_print_func_field - print a field and a format for function pointers
+ * @s: The seq to print to
+ * @fmt: The printf format to print the field with.
+ * @event: the event that the field is for
+ * @name: The name of the field
+ * @record: The record with the field name.
+ * @err: print default error if failed.
+ *
+ * Returns: 0 on success, -1 field not found, or 1 if buffer is full.
+ */
+int pevent_print_func_field(struct trace_seq *s, const char *fmt,
+			    struct event_format *event, const char *name,
+			    struct pevent_record *record, int err)
+{
+	struct format_field *field = pevent_find_field(event, name);
+	struct pevent *pevent = event->pevent;
+	unsigned long long val;
+	struct func_map *func;
+	char tmp[128];
+
+	if (!field)
+		goto failed;
+
+	if (pevent_read_number_field(field, record->data, &val))
+		goto failed;
+
+	func = find_func(pevent, val);
+
+	if (func)
+		snprintf(tmp, 128, "%s/0x%llx", func->func, func->addr - val);
+	else
+		sprintf(tmp, "0x%08llx", val);
+
+	return trace_seq_printf(s, fmt, tmp);
+
+ failed:
+	if (err)
+		trace_seq_printf(s, "CAN'T FIND FIELD \"%s\"", name);
+	return -1;
+}
+
+static void free_func_handle(struct pevent_function_handler *func)
+{
+	struct pevent_func_params *params;
+
+	free(func->name);
+
+	while (func->params) {
+		params = func->params;
+		func->params = params->next;
+		free(params);
+	}
+
+	free(func);
+}
+
+/**
+ * pevent_register_print_function - register a helper function
+ * @pevent: the handle to the pevent
+ * @func: the function to process the helper function
+ * @ret_type: the return type of the helper function
+ * @name: the name of the helper function
+ * @parameters: A list of enum pevent_func_arg_type
+ *
+ * Some events may have helper functions in the print format arguments.
+ * This allows a plugin to dynamically create a way to process one
+ * of these functions.
+ *
+ * The @parameters is a variable list of pevent_func_arg_type enums that
+ * must end with PEVENT_FUNC_ARG_VOID.
+ */
+int pevent_register_print_function(struct pevent *pevent,
+				   pevent_func_handler func,
+				   enum pevent_func_arg_type ret_type,
+				   char *name, ...)
+{
+	struct pevent_function_handler *func_handle;
+	struct pevent_func_params **next_param;
+	struct pevent_func_params *param;
+	enum pevent_func_arg_type type;
+	va_list ap;
+	int ret;
+
+	func_handle = find_func_handler(pevent, name);
+	if (func_handle) {
+		/*
+		 * This is most like caused by the users own
+		 * plugins updating the function. This overrides the
+		 * system defaults.
+		 */
+		pr_stat("override of function helper '%s'", name);
+		remove_func_handler(pevent, name);
+	}
+
+	func_handle = calloc(1, sizeof(*func_handle));
+	if (!func_handle) {
+		do_warning("Failed to allocate function handler");
+		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+	}
+
+	func_handle->ret_type = ret_type;
+	func_handle->name = strdup(name);
+	func_handle->func = func;
+	if (!func_handle->name) {
+		do_warning("Failed to allocate function name");
+		free(func_handle);
+		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+	}
+
+	next_param = &(func_handle->params);
+	va_start(ap, name);
+	for (;;) {
+		type = va_arg(ap, enum pevent_func_arg_type);
+		if (type == PEVENT_FUNC_ARG_VOID)
+			break;
+
+		if (type >= PEVENT_FUNC_ARG_MAX_TYPES) {
+			do_warning("Invalid argument type %d", type);
+			ret = PEVENT_ERRNO__INVALID_ARG_TYPE;
+			goto out_free;
+		}
+
+		param = malloc(sizeof(*param));
+		if (!param) {
+			do_warning("Failed to allocate function param");
+			ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
+			goto out_free;
+		}
+		param->type = type;
+		param->next = NULL;
+
+		*next_param = param;
+		next_param = &(param->next);
+
+		func_handle->nr_args++;
+	}
+	va_end(ap);
+
+	func_handle->next = pevent->func_handlers;
+	pevent->func_handlers = func_handle;
+
+	return 0;
+ out_free:
+	va_end(ap);
+	free_func_handle(func_handle);
+	return ret;
+}
+
+/**
+ * pevent_unregister_print_function - unregister a helper function
+ * @pevent: the handle to the pevent
+ * @func: the function to process the helper function
+ * @name: the name of the helper function
+ *
+ * This function removes existing print handler for function @name.
+ *
+ * Returns 0 if the handler was removed successully, -1 otherwise.
+ */
+int pevent_unregister_print_function(struct pevent *pevent,
+				     pevent_func_handler func, char *name)
+{
+	struct pevent_function_handler *func_handle;
+
+	func_handle = find_func_handler(pevent, name);
+	if (func_handle && func_handle->func == func) {
+		remove_func_handler(pevent, name);
+		return 0;
+	}
+	return -1;
+}
+
+static struct event_format *pevent_search_event(struct pevent *pevent, int id,
+						const char *sys_name,
+						const char *event_name)
+{
+	struct event_format *event;
+
+	if (id >= 0) {
+		/* search by id */
+		event = pevent_find_event(pevent, id);
+		if (!event)
+			return NULL;
+		if (event_name && (strcmp(event_name, event->name) != 0))
+			return NULL;
+		if (sys_name && (strcmp(sys_name, event->system) != 0))
+			return NULL;
+	} else {
+		event = pevent_find_event_by_name(pevent, sys_name, event_name);
+		if (!event)
+			return NULL;
+	}
+	return event;
+}
+
+/**
+ * pevent_register_event_handler - register a way to parse an event
+ * @pevent: the handle to the pevent
+ * @id: the id of the event to register
+ * @sys_name: the system name the event belongs to
+ * @event_name: the name of the event
+ * @func: the function to call to parse the event information
+ * @context: the data to be passed to @func
+ *
+ * This function allows a developer to override the parsing of
+ * a given event. If for some reason the default print format
+ * is not sufficient, this function will register a function
+ * for an event to be used to parse the data instead.
+ *
+ * If @id is >= 0, then it is used to find the event.
+ * else @sys_name and @event_name are used.
+ */
+int pevent_register_event_handler(struct pevent *pevent, int id,
+				  const char *sys_name, const char *event_name,
+				  pevent_event_handler_func func, void *context)
+{
+	struct event_format *event;
+	struct event_handler *handle;
+
+	event = pevent_search_event(pevent, id, sys_name, event_name);
+	if (event == NULL)
+		goto not_found;
+
+	pr_stat("overriding event (%d) %s:%s with new print handler",
+		event->id, event->system, event->name);
+
+	event->handler = func;
+	event->context = context;
+	return 0;
+
+ not_found:
+	/* Save for later use. */
+	handle = calloc(1, sizeof(*handle));
+	if (!handle) {
+		do_warning("Failed to allocate event handler");
+		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+	}
+
+	handle->id = id;
+	if (event_name)
+		handle->event_name = strdup(event_name);
+	if (sys_name)
+		handle->sys_name = strdup(sys_name);
+
+	if ((event_name && !handle->event_name) ||
+	    (sys_name && !handle->sys_name)) {
+		do_warning("Failed to allocate event/sys name");
+		free((void *)handle->event_name);
+		free((void *)handle->sys_name);
+		free(handle);
+		return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+	}
+
+	handle->func = func;
+	handle->next = pevent->handlers;
+	pevent->handlers = handle;
+	handle->context = context;
+
+	return -1;
+}
+
+static int handle_matches(struct event_handler *handler, int id,
+			  const char *sys_name, const char *event_name,
+			  pevent_event_handler_func func, void *context)
+{
+	if (id >= 0 && id != handler->id)
+		return 0;
+
+	if (event_name && (strcmp(event_name, handler->event_name) != 0))
+		return 0;
+
+	if (sys_name && (strcmp(sys_name, handler->sys_name) != 0))
+		return 0;
+
+	if (func != handler->func || context != handler->context)
+		return 0;
+
+	return 1;
+}
+
+/**
+ * pevent_unregister_event_handler - unregister an existing event handler
+ * @pevent: the handle to the pevent
+ * @id: the id of the event to unregister
+ * @sys_name: the system name the handler belongs to
+ * @event_name: the name of the event handler
+ * @func: the function to call to parse the event information
+ * @context: the data to be passed to @func
+ *
+ * This function removes existing event handler (parser).
+ *
+ * If @id is >= 0, then it is used to find the event.
+ * else @sys_name and @event_name are used.
+ *
+ * Returns 0 if handler was removed successfully, -1 if event was not found.
+ */
+int pevent_unregister_event_handler(struct pevent *pevent, int id,
+				    const char *sys_name, const char *event_name,
+				    pevent_event_handler_func func, void *context)
+{
+	struct event_format *event;
+	struct event_handler *handle;
+	struct event_handler **next;
+
+	event = pevent_search_event(pevent, id, sys_name, event_name);
+	if (event == NULL)
+		goto not_found;
+
+	if (event->handler == func && event->context == context) {
+		pr_stat("removing override handler for event (%d) %s:%s. Going back to default handler.",
+			event->id, event->system, event->name);
+
+		event->handler = NULL;
+		event->context = NULL;
+		return 0;
+	}
+
+not_found:
+	for (next = &pevent->handlers; *next; next = &(*next)->next) {
+		handle = *next;
+		if (handle_matches(handle, id, sys_name, event_name,
+				   func, context))
+			break;
+	}
+
+	if (!(*next))
+		return -1;
+
+	*next = handle->next;
+	free_handler(handle);
+
+	return 0;
+}
+
+/**
+ * pevent_alloc - create a pevent handle
+ */
+struct pevent *pevent_alloc(void)
+{
+	struct pevent *pevent = calloc(1, sizeof(*pevent));
+
+	if (pevent)
+		pevent->ref_count = 1;
+
+	return pevent;
+}
+
+void pevent_ref(struct pevent *pevent)
+{
+	pevent->ref_count++;
+}
+
+void pevent_free_format_field(struct format_field *field)
+{
+	free(field->type);
+	free(field->name);
+	free(field);
+}
+
+static void free_format_fields(struct format_field *field)
+{
+	struct format_field *next;
+
+	while (field) {
+		next = field->next;
+		pevent_free_format_field(field);
+		field = next;
+	}
+}
+
+static void free_formats(struct format *format)
+{
+	free_format_fields(format->common_fields);
+	free_format_fields(format->fields);
+}
+
+void pevent_free_format(struct event_format *event)
+{
+	free(event->name);
+	free(event->system);
+
+	free_formats(&event->format);
+
+	free(event->print_fmt.format);
+	free_args(event->print_fmt.args);
+
+	free(event);
+}
+
+/**
+ * pevent_free - free a pevent handle
+ * @pevent: the pevent handle to free
+ */
+void pevent_free(struct pevent *pevent)
+{
+	struct cmdline_list *cmdlist, *cmdnext;
+	struct func_list *funclist, *funcnext;
+	struct printk_list *printklist, *printknext;
+	struct pevent_function_handler *func_handler;
+	struct event_handler *handle;
+	int i;
+
+	if (!pevent)
+		return;
+
+	cmdlist = pevent->cmdlist;
+	funclist = pevent->funclist;
+	printklist = pevent->printklist;
+
+	pevent->ref_count--;
+	if (pevent->ref_count)
+		return;
+
+	if (pevent->cmdlines) {
+		for (i = 0; i < pevent->cmdline_count; i++)
+			free(pevent->cmdlines[i].comm);
+		free(pevent->cmdlines);
+	}
+
+	while (cmdlist) {
+		cmdnext = cmdlist->next;
+		free(cmdlist->comm);
+		free(cmdlist);
+		cmdlist = cmdnext;
+	}
+
+	if (pevent->func_map) {
+		for (i = 0; i < (int)pevent->func_count; i++) {
+			free(pevent->func_map[i].func);
+			free(pevent->func_map[i].mod);
+		}
+		free(pevent->func_map);
+	}
+
+	while (funclist) {
+		funcnext = funclist->next;
+		free(funclist->func);
+		free(funclist->mod);
+		free(funclist);
+		funclist = funcnext;
+	}
+
+	while (pevent->func_handlers) {
+		func_handler = pevent->func_handlers;
+		pevent->func_handlers = func_handler->next;
+		free_func_handle(func_handler);
+	}
+
+	if (pevent->printk_map) {
+		for (i = 0; i < (int)pevent->printk_count; i++)
+			free(pevent->printk_map[i].printk);
+		free(pevent->printk_map);
+	}
+
+	while (printklist) {
+		printknext = printklist->next;
+		free(printklist->printk);
+		free(printklist);
+		printklist = printknext;
+	}
+
+	for (i = 0; i < pevent->nr_events; i++)
+		pevent_free_format(pevent->events[i]);
+
+	while (pevent->handlers) {
+		handle = pevent->handlers;
+		pevent->handlers = handle->next;
+		free_handler(handle);
+	}
+
+	free(pevent->trace_clock);
+	free(pevent->events);
+	free(pevent->sort_events);
+
+	free(pevent);
+}
+
+void pevent_unref(struct pevent *pevent)
+{
+	pevent_free(pevent);
+}