diff options
Diffstat (limited to 'src/udev/collect')
-rw-r--r-- | src/udev/collect/collect.c | 473 |
1 files changed, 473 insertions, 0 deletions
diff --git a/src/udev/collect/collect.c b/src/udev/collect/collect.c new file mode 100644 index 0000000000..076fe479e2 --- /dev/null +++ b/src/udev/collect/collect.c @@ -0,0 +1,473 @@ +/* + * Collect variables across events. + * + * usage: collect [--add|--remove] <checkpoint> <id> <idlist> + * + * Adds ID <id> to the list governed by <checkpoint>. + * <id> must be part of the ID list <idlist>. + * If all IDs given by <idlist> are listed (ie collect has been + * invoked for each ID in <idlist>) collect returns 0, the + * number of missing IDs otherwise. + * A negative number is returned on error. + * + * Copyright(C) 2007, Hannes Reinecke <hare@suse.de> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include <stdio.h> +#include <stdlib.h> +#include <stddef.h> +#include <unistd.h> +#include <signal.h> +#include <fcntl.h> +#include <errno.h> +#include <string.h> +#include <getopt.h> +#include <sys/types.h> +#include <sys/stat.h> + +#include "libudev.h" +#include "libudev-private.h" + +#define BUFSIZE 16 +#define UDEV_ALARM_TIMEOUT 180 + +enum collect_state { + STATE_NONE, + STATE_OLD, + STATE_CONFIRMED, +}; + +struct _mate { + struct udev_list_node node; + char *name; + enum collect_state state; +}; + +static struct udev_list_node bunch; +static int debug; + +/* This can increase dynamically */ +static size_t bufsize = BUFSIZE; + +static struct _mate *node_to_mate(struct udev_list_node *node) +{ + char *mate; + + mate = (char *)node; + mate -= offsetof(struct _mate, node); + return (struct _mate *)mate; +} + +static void sig_alrm(int signo) +{ + exit(4); +} + +static void usage(void) +{ + printf("usage: collect [--add|--remove] [--debug] <checkpoint> <id> <idlist>\n" + "\n" + " Adds ID <id> to the list governed by <checkpoint>.\n" + " <id> must be part of the list <idlist>.\n" + " If all IDs given by <idlist> are listed (ie collect has been\n" + " invoked for each ID in <idlist>) collect returns 0, the\n" + " number of missing IDs otherwise.\n" + " On error a negative number is returned.\n" + "\n"); +} + +/* + * prepare + * + * Prepares the database file + */ +static int prepare(char *dir, char *filename) +{ + struct stat statbuf; + char buf[512]; + int fd; + + if (stat(dir, &statbuf) < 0) + mkdir(dir, 0700); + + sprintf(buf, "%s/%s", dir, filename); + + fd = open(buf,O_RDWR|O_CREAT, S_IRUSR|S_IWUSR); + if (fd < 0) + fprintf(stderr, "Cannot open %s: %s\n", buf, strerror(errno)); + + if (lockf(fd,F_TLOCK,0) < 0) { + if (debug) + fprintf(stderr, "Lock taken, wait for %d seconds\n", UDEV_ALARM_TIMEOUT); + if (errno == EAGAIN || errno == EACCES) { + alarm(UDEV_ALARM_TIMEOUT); + lockf(fd, F_LOCK, 0); + if (debug) + fprintf(stderr, "Acquired lock on %s\n", buf); + } else { + if (debug) + fprintf(stderr, "Could not get lock on %s: %s\n", buf, strerror(errno)); + } + } + + return fd; +} + +/* + * Read checkpoint file + * + * Tricky reading this. We allocate a buffer twice as large + * as we're going to read. Then we read into the upper half + * of that buffer and start parsing. + * Once we do _not_ find end-of-work terminator (whitespace + * character) we move the upper half to the lower half, + * adjust the read pointer and read the next bit. + * Quite clever methinks :-) + * I should become a programmer ... + * + * Yes, one could have used fgets() for this. But then we'd + * have to use freopen etc which I found quite tedious. + */ +static int checkout(int fd) +{ + int len; + char *buf, *ptr, *word = NULL; + struct _mate *him; + + restart: + len = bufsize >> 1; + buf = calloc(1,bufsize + 1); + if (!buf) { + fprintf(stderr, "Out of memory\n"); + return -1; + } + memset(buf, ' ', bufsize); + ptr = buf + len; + while ((read(fd, buf + len, len)) > 0) { + while (ptr && *ptr) { + word = ptr; + ptr = strpbrk(word," \n\t\r"); + if (!ptr && word < (buf + len)) { + bufsize = bufsize << 1; + if (debug) + fprintf(stderr, "ID overflow, restarting with size %zi\n", bufsize); + free(buf); + lseek(fd, 0, SEEK_SET); + goto restart; + } + if (ptr) { + *ptr = '\0'; + ptr++; + if (!strlen(word)) + continue; + + if (debug) + fprintf(stderr, "Found word %s\n", word); + him = malloc(sizeof (struct _mate)); + him->name = strdup(word); + him->state = STATE_OLD; + udev_list_node_append(&him->node, &bunch); + word = NULL; + } + } + memcpy(buf, buf + len, len); + memset(buf + len, ' ', len); + + if (!ptr) + ptr = word; + if (!ptr) + break; + ptr -= len; + } + + free(buf); + return 0; +} + +/* + * invite + * + * Adds a new ID 'us' to the internal list, + * marks it as confirmed. + */ +static void invite(char *us) +{ + struct udev_list_node *him_node; + struct _mate *who = NULL; + + if (debug) + fprintf(stderr, "Adding ID '%s'\n", us); + + udev_list_node_foreach(him_node, &bunch) { + struct _mate *him = node_to_mate(him_node); + + if (!strcmp(him->name, us)) { + him->state = STATE_CONFIRMED; + who = him; + } + } + if (debug && !who) + fprintf(stderr, "ID '%s' not in database\n", us); + +} + +/* + * reject + * + * Marks the ID 'us' as invalid, + * causing it to be removed when the + * list is written out. + */ +static void reject(char *us) +{ + struct udev_list_node *him_node; + struct _mate *who = NULL; + + if (debug) + fprintf(stderr, "Removing ID '%s'\n", us); + + udev_list_node_foreach(him_node, &bunch) { + struct _mate *him = node_to_mate(him_node); + + if (!strcmp(him->name, us)) { + him->state = STATE_NONE; + who = him; + } + } + if (debug && !who) + fprintf(stderr, "ID '%s' not in database\n", us); +} + +/* + * kickout + * + * Remove all IDs in the internal list which are not part + * of the list passed via the commandline. + */ +static void kickout(void) +{ + struct udev_list_node *him_node; + struct udev_list_node *tmp; + + udev_list_node_foreach_safe(him_node, tmp, &bunch) { + struct _mate *him = node_to_mate(him_node); + + if (him->state == STATE_OLD) { + udev_list_node_remove(&him->node); + free(him->name); + free(him); + } + } +} + +/* + * missing + * + * Counts all missing IDs in the internal list. + */ +static int missing(int fd) +{ + char *buf; + int ret = 0; + struct udev_list_node *him_node; + + buf = malloc(bufsize); + if (!buf) + return -1; + + udev_list_node_foreach(him_node, &bunch) { + struct _mate *him = node_to_mate(him_node); + + if (him->state == STATE_NONE) { + ret++; + } else { + while (strlen(him->name)+1 >= bufsize) { + char *tmpbuf; + + bufsize = bufsize << 1; + tmpbuf = realloc(buf, bufsize); + if (!tmpbuf) { + free(buf); + return -1; + } + buf = tmpbuf; + } + snprintf(buf, strlen(him->name)+2, "%s ", him->name); + write(fd, buf, strlen(buf)); + } + } + + free(buf); + return ret; +} + +/* + * everybody + * + * Prints out the status of the internal list. + */ +static void everybody(void) +{ + struct udev_list_node *him_node; + const char *state = ""; + + udev_list_node_foreach(him_node, &bunch) { + struct _mate *him = node_to_mate(him_node); + + switch (him->state) { + case STATE_NONE: + state = "none"; + break; + case STATE_OLD: + state = "old"; + break; + case STATE_CONFIRMED: + state = "confirmed"; + break; + } + fprintf(stderr, "ID: %s=%s\n", him->name, state); + } +} + +int main(int argc, char **argv) +{ + struct udev *udev; + static const struct option options[] = { + { "add", no_argument, NULL, 'a' }, + { "remove", no_argument, NULL, 'r' }, + { "debug", no_argument, NULL, 'd' }, + { "help", no_argument, NULL, 'h' }, + {} + }; + int argi; + char *checkpoint, *us; + int fd; + int i; + int ret = EXIT_SUCCESS; + int prune = 0; + char tmpdir[UTIL_PATH_SIZE]; + + udev = udev_new(); + if (udev == NULL) { + ret = EXIT_FAILURE; + goto exit; + } + + while (1) { + int option; + + option = getopt_long(argc, argv, "ardh", options, NULL); + if (option == -1) + break; + + switch (option) { + case 'a': + prune = 0; + break; + case 'r': + prune = 1; + break; + case 'd': + debug = 1; + break; + case 'h': + usage(); + goto exit; + default: + ret = 1; + goto exit; + } + } + + argi = optind; + if (argi + 2 > argc) { + printf("Missing parameter(s)\n"); + ret = 1; + goto exit; + } + checkpoint = argv[argi++]; + us = argv[argi++]; + + if (signal(SIGALRM, sig_alrm) == SIG_ERR) { + fprintf(stderr, "Cannot set SIGALRM: %s\n", strerror(errno)); + ret = 2; + goto exit; + } + + udev_list_node_init(&bunch); + + if (debug) + fprintf(stderr, "Using checkpoint '%s'\n", checkpoint); + + util_strscpyl(tmpdir, sizeof(tmpdir), udev_get_run_path(udev), "/collect", NULL); + fd = prepare(tmpdir, checkpoint); + if (fd < 0) { + ret = 3; + goto out; + } + + if (checkout(fd) < 0) { + ret = 2; + goto out; + } + + for (i = argi; i < argc; i++) { + struct udev_list_node *him_node; + struct _mate *who; + + who = NULL; + udev_list_node_foreach(him_node, &bunch) { + struct _mate *him = node_to_mate(him_node); + + if (!strcmp(him->name, argv[i])) + who = him; + } + if (!who) { + struct _mate *him; + + if (debug) + fprintf(stderr, "ID %s: not in database\n", argv[i]); + him = malloc(sizeof (struct _mate)); + him->name = malloc(strlen(argv[i]) + 1); + strcpy(him->name, argv[i]); + him->state = STATE_NONE; + udev_list_node_append(&him->node, &bunch); + } else { + if (debug) + fprintf(stderr, "ID %s: found in database\n", argv[i]); + who->state = STATE_CONFIRMED; + } + } + + if (prune) + reject(us); + else + invite(us); + + if (debug) { + everybody(); + fprintf(stderr, "Prune lists\n"); + } + kickout(); + + lseek(fd, 0, SEEK_SET); + ftruncate(fd, 0); + ret = missing(fd); + + lockf(fd, F_ULOCK, 0); + close(fd); +out: + if (debug) + everybody(); + if (ret >= 0) + printf("COLLECT_%s=%d\n", checkpoint, ret); +exit: + udev_unref(udev); + return ret; +} |