path: root/src/shared/util.h

/***
  This file is part of eudev, forked from systemd.

  Copyright 2010 Lennart Poettering

  systemd 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; either version 2.1 of the License, or
  (at your option) any later version.

  systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#pragma once

#include <fcntl.h>
#include <string.h>
#include <time.h>
#include <stdlib.h>
#include <stdio.h>
#include <sched.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <stddef.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/inotify.h>

#include "time-util.h"
#include "missing.h"
#include "config.h"

#include "macro.h"
#include "missing.h"
#include "formats-util.h"

/* What is interpreted as whitespace? */
#define WHITESPACE " \t\n\r"
#define NEWLINE    "\n\r"
#define QUOTES     "\"\'"
#define COMMENTS   "#;"
#define GLOB_CHARS "*?["

#define FORMAT_BYTES_MAX 8

size_t page_size(void) _pure_;
#define PAGE_ALIGN(l) ALIGN_TO((l), page_size())

#define streq(a,b) (strcmp((a),(b)) == 0)
#define strneq(a, b, n) (strncmp((a), (b), (n)) == 0)
#define strcaseeq(a,b) (strcasecmp((a),(b)) == 0)
#define strncaseeq(a, b, n) (strncasecmp((a), (b), (n)) == 0)

bool streq_ptr(const char *a, const char *b) _pure_;

#define new(t, n) ((t*) malloc_multiply(sizeof(t), (n)))

#define new0(t, n) ((t*) calloc((n), sizeof(t)))
#define malloc0(n) (calloc((n), 1))

static inline const char* one_zero(bool b) {
        return b ? "1" : "0";
}

static inline bool isempty(const char *p) {
        return !p || !p[0];
}

static inline char *startswith(const char *s, const char *prefix) {
        size_t l;

        l = strlen(prefix);
        if (strncmp(s, prefix, l) == 0)
                return (char*) s + l;

        return NULL;
}

char *endswith(const char *s, const char *postfix) _pure_;

int close_nointr(int fd);
int safe_close(int fd);

void close_many(const int fds[], unsigned n_fd);

int parse_uid(const char *s, uid_t* ret_uid);
#define parse_gid(s, ret_uid) parse_uid(s, ret_uid)

int safe_atou(const char *s, unsigned *ret_u);
int safe_atoi(const char *s, int *ret_i);

int safe_atollu(const char *s, unsigned long long *ret_u);
int safe_atolli(const char *s, long long int *ret_i);


#if LONG_MAX == INT_MAX
static inline int safe_atolu(const char *s, unsigned long *ret_u) {
        assert_cc(sizeof(unsigned long) == sizeof(unsigned));
        return safe_atou(s, (unsigned*) ret_u);
}
static inline int safe_atoli(const char *s, long int *ret_u) {
        assert_cc(sizeof(long int) == sizeof(int));
        return safe_atoi(s, (int*) ret_u);
}
#else
static inline int safe_atolu(const char *s, unsigned long *ret_u) {
        assert_cc(sizeof(unsigned long) == sizeof(unsigned long long));
        return safe_atollu(s, (unsigned long long*) ret_u);
}
static inline int safe_atoli(const char *s, long int *ret_u) {
        assert_cc(sizeof(long int) == sizeof(long long int));
        return safe_atolli(s, (long long int*) ret_u);
}
#endif

static inline int safe_atou64(const char *s, uint64_t *ret_u) {
        assert_cc(sizeof(uint64_t) == sizeof(unsigned long long));
        return safe_atollu(s, (unsigned long long*) ret_u);
}
const char* split(const char **state, size_t *l, const char *separator, bool quoted);

#define FOREACH_WORD_QUOTED(word, length, s, state)                     \
        _FOREACH_WORD(word, length, s, WHITESPACE, true, state)

#define _FOREACH_WORD(word, length, s, separator, quoted, state)        \
        for ((state) = (s), (word) = split(&(state), &(length), (separator), (quoted)); (word); (word) = split(&(state), &(length), (separator), (quoted)))

char *strappend(const char *s, const char *suffix);
char *strnappend(const char *s, const char *suffix, size_t length);

char *truncate_nl(char *s);

int rmdir_parents(const char *path, const char *stop);

char hexchar(int x) _const_;
int unhexchar(char c) _const_;
char octchar(int x) _const_;
int unoctchar(char c) _const_;

char *cescape(const char *s);
size_t cescape_char(char c, char *buf);
char *xescape(const char *s, const char *bad);

bool dirent_is_file_with_suffix(const struct dirent *de, const char *suffix) _pure_;

bool hidden_file(const char *filename) _pure_;

/* For basic lookup tables with strictly enumerated entries */
#define _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,scope)          \
        scope const char *name##_to_string(type i) {                    \
                if (i < 0 || i >= (type) ELEMENTSOF(name##_table))      \
                        return NULL;                                    \
                return name##_table[i];                                 \
        }

#define _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING(name,type,scope)        \
        scope type name##_from_string(const char *s) {                  \
                type i;                                                 \
                if (!s)                                                 \
                        return (type) -1;                               \
                for (i = 0; i < (type)ELEMENTSOF(name##_table); i++)    \
                        if (name##_table[i] &&                          \
                            streq(name##_table[i], s))                  \
                                return i;                               \
                return (type) -1;                                       \
        }

#define _DEFINE_STRING_TABLE_LOOKUP(name,type,scope)                    \
        _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,scope)          \
        _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING(name,type,scope)        \
        struct __useless_struct_to_allow_trailing_semicolon__

#define DEFINE_STRING_TABLE_LOOKUP(name,type) _DEFINE_STRING_TABLE_LOOKUP(name,type,)
#define DEFINE_PRIVATE_STRING_TABLE_LOOKUP(name,type) _DEFINE_STRING_TABLE_LOOKUP(name,type,static)
#define DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(name,type) _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,static)
#define DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING(name,type) _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING(name,type,static)

/* For string conversions where numbers are also acceptable */
#define DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(name,type,max)         \
        int name##_to_string_alloc(type i, char **str) {                \
                char *s;                                                \
                int r;                                                  \
                if (i < 0 || i > max)                                   \
                        return -ERANGE;                                 \
                if (i < (type) ELEMENTSOF(name##_table)) {              \
                        s = strdup(name##_table[i]);                    \
                        if (!s)                                         \
                                return log_oom();                       \
                } else {                                                \
                        r = asprintf(&s, "%i", i);                      \
                        if (r < 0)                                      \
                                return log_oom();                       \
                }                                                       \
                *str = s;                                               \
                return 0;                                               \
        }                                                               \
        type name##_from_string(const char *s) {                        \
                type i;                                                 \
                unsigned u = 0;                                         \
                assert(s);                                              \
                for (i = 0; i < (type)ELEMENTSOF(name##_table); i++)    \
                        if (name##_table[i] &&                          \
                            streq(name##_table[i], s))                  \
                                return i;                               \
                if (safe_atou(s, &u) >= 0 && u <= max)                  \
                        return (type) u;                                \
                return (type) -1;                                       \
        }                                                               \
        struct __useless_struct_to_allow_trailing_semicolon__

int flush_fd(int fd);

int fopen_temporary(const char *path, FILE **_f, char **_temp_path);

ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll);
int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll);

char* dirname_malloc(const char *path);

int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid);

#define xsprintf(buf, fmt, ...) assert_se((size_t) snprintf(buf, ELEMENTSOF(buf), fmt, __VA_ARGS__) < ELEMENTSOF(buf))

int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gid, mode_t mode);
int touch(const char *path);

bool null_or_empty(struct stat *st) _pure_;
int null_or_empty_path(const char *fn);
int null_or_empty_fd(int fd);

bool nulstr_contains(const char*nulstr, const char *needle);

int get_user_creds(const char **username, uid_t *uid, gid_t *gid, const char **home, const char **shell);
int get_group_creds(const char **groupname, gid_t *gid);

char *strjoin(const char *x, ...) _sentinel_;

bool is_main_thread(void);

#define NULSTR_FOREACH(i, l)                                    \
        for ((i) = (l); (i) && *(i); (i) = strchr((i), 0)+1)

#define NULSTR_FOREACH_PAIR(i, j, l)                             \
        for ((i) = (l), (j) = strchr((i), 0)+1; (i) && *(i); (i) = strchr((j), 0)+1, (j) = *(i) ? strchr((i), 0)+1 : (i))

int ioprio_class_to_string_alloc(int i, char **s);
int ioprio_class_from_string(const char *s);

const char *sigchld_code_to_string(int i) _const_;
int sigchld_code_from_string(const char *s) _pure_;

int log_facility_unshifted_to_string_alloc(int i, char **s);
int log_facility_unshifted_from_string(const char *s);

int log_level_to_string_alloc(int i, char **s);
int log_level_from_string(const char *s);

int sched_policy_to_string_alloc(int i, char **s);
int sched_policy_from_string(const char *s);

const char *rlimit_to_string(int i) _const_;
int rlimit_from_string(const char *s) _pure_;

int ip_tos_to_string_alloc(int i, char **s);
int ip_tos_from_string(const char *s);

const char *signal_to_string(int i) _const_;

extern int saved_argc;
extern char **saved_argv;

int fd_wait_for_event(int fd, int event, usec_t timeout);
int fd_inc_sndbuf(int fd, size_t n);

bool in_initrd(void);

static inline void freep(void *p) {
        free(*(void**) p);
}

static inline void closep(int *fd) {
        safe_close(*fd);
}

static inline void umaskp(mode_t *u) {
        umask(*u);
}

DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, fclose);
DEFINE_TRIVIAL_CLEANUP_FUNC(DIR*, closedir);
#define _cleanup_free_ _cleanup_(freep)
#define _cleanup_close_ _cleanup_(closep)
#define _cleanup_umask_ _cleanup_(umaskp)
#define _cleanup_fclose_ _cleanup_(fclosep)
#define _cleanup_closedir_ _cleanup_(closedirp)

_malloc_  _alloc_(1, 2) static inline void *malloc_multiply(size_t a, size_t b) {
        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
                return NULL;

        return malloc(a * b);
}

_alloc_(2, 3) static inline void *realloc_multiply(void *p, size_t a, size_t b) {
        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
                return NULL;

        return realloc(p, a * b);
}

bool filename_is_valid(const char *p) _pure_;
/**
 * Check if a string contains any glob patterns.
 */
_pure_ static inline bool string_is_glob(const char *p) {
        return !!strpbrk(p, GLOB_CHARS);
}

void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size,
                 int (*compar) (const void *, const void *, void *),
                 void *arg);

#define FOREACH_LINE(line, f, on_error)                         \
        for (;;)                                                \
                if (!fgets(line, sizeof(line), f)) {            \
                        if (ferror(f)) {                        \
                                on_error;                       \
                        }                                       \
                        break;                                  \
                } else

static inline void *mempset(void *s, int c, size_t n) {
        memset(s, c, n);
        return (uint8_t*)s + n;
}


void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size);
#define GREEDY_REALLOC(array, allocated, need)                          \
        greedy_realloc((void**) &(array), &(allocated), (need), sizeof((array)[0]))
static inline void _reset_errno_(int *saved_errno) {
        errno = *saved_errno;
}

#define PROTECT_ERRNO _cleanup_(_reset_errno_) __attribute__((unused)) int _saved_errno_ = errno

static inline unsigned log2u(unsigned x) {
        assert(x > 0);

        return sizeof(unsigned) * 8 - __builtin_clz(x) - 1;
}

static inline unsigned log2u_round_up(unsigned x) {
        assert(x > 0);

        if (x == 1)
                return 0;

        return log2u(x - 1) + 1;
}

int unlink_noerrno(const char *path);

#define strjoina(a, ...)                                                \
        ({                                                              \
                const char *_appendees_[] = { a, __VA_ARGS__ };         \
                char *_d_, *_p_;                                        \
                int _len_ = 0;                                          \
                unsigned _i_;                                           \
                for (_i_ = 0; _i_ < ELEMENTSOF(_appendees_) && _appendees_[_i_]; _i_++) \
                        _len_ += strlen(_appendees_[_i_]);              \
                _p_ = _d_ = alloca(_len_ + 1);                          \
                for (_i_ = 0; _i_ < ELEMENTSOF(_appendees_) && _appendees_[_i_]; _i_++) \
                        _p_ = stpcpy(_p_, _appendees_[_i_]);            \
                *_p_ = 0;                                               \
                _d_;                                                    \
        })

static inline void qsort_safe(void *base, size_t nmemb, size_t size,
                              int (*compar)(const void *, const void *)) {
        if (nmemb) {
                assert(base);
                qsort(base, nmemb, size, compar);
        }
}

int proc_cmdline(char **ret);
int parse_proc_cmdline(int (*parse_word)(const char *key, const char *value));
int getpeercred(int fd, struct ucred *ucred);

#if HAVE_DECL_MKOSTEMP
int mkostemp_safe(char *pattern, int flags);
#else
int mkstemp_safe(char *pattern);
#endif

union file_handle_union {
        struct file_handle handle;
        char padding[sizeof(struct file_handle) + MAX_HANDLE_SZ];
};
#define FILE_HANDLE_INIT { .handle.handle_bytes = MAX_HANDLE_SZ }

int tempfn_xxxxxx(const char *p, char **ret);

int is_dir(const char *path, bool follow);

typedef enum UnquoteFlags {
        UNQUOTE_RELAX     = 1,
        UNQUOTE_CUNESCAPE = 2,
} UnquoteFlags;

int unquote_first_word(const char **p, char **ret, UnquoteFlags flags);

int execute_command(const char *command, char *const argv[]);

#define INOTIFY_EVENT_MAX (sizeof(struct inotify_event) + NAME_MAX + 1)

#define FOREACH_INOTIFY_EVENT(e, buffer, sz) \
        for ((e) = &buffer.ev;                                \
             (uint8_t*) (e) < (uint8_t*) (buffer.raw) + (sz); \
             (e) = (struct inotify_event*) ((uint8_t*) (e) + sizeof(struct inotify_event) + (e)->len))

union inotify_event_buffer {
        struct inotify_event ev;
        uint8_t raw[INOTIFY_EVENT_MAX];
};

void cmsg_close_all(struct msghdr *mh);