1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 This file is part of systemd.
5 Copyright 2010 Lennart Poettering
7 systemd is free software; you can redistribute it and/or modify it
8 under the terms of the GNU Lesser General Public License as published by
9 the Free Software Foundation; either version 2.1 of the License, or
10 (at your option) any later version.
12 systemd is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public License
18 along with systemd; If not, see <http://www.gnu.org/licenses/>.
26 #include <stdio_ext.h>
31 #include <sys/types.h>
34 #include "alloc-util.h"
42 #include "hexdecoct.h"
46 #include "parse-util.h"
47 #include "path-util.h"
48 #include "process-util.h"
49 #include "random-util.h"
50 #include "stdio-util.h"
51 #include "string-util.h"
53 //#include "time-util.h"
54 #include "umask-util.h"
57 #define READ_FULL_BYTES_MAX (4U*1024U*1024U)
59 int write_string_stream_ts(
62 WriteStringFileFlags flags,
63 struct timespec *ts) {
71 if (fputs(line, f) == EOF)
74 if (!(flags & WRITE_STRING_FILE_AVOID_NEWLINE) && !endswith(line, "\n"))
75 if (fputc('\n', f) == EOF)
79 struct timespec twice[2] = {*ts, *ts};
81 if (futimens(fileno(f), twice) < 0)
85 if (flags & WRITE_STRING_FILE_SYNC)
86 return fflush_sync_and_check(f);
88 return fflush_and_check(f);
91 static int write_string_file_atomic(
94 WriteStringFileFlags flags,
95 struct timespec *ts) {
97 _cleanup_fclose_ FILE *f = NULL;
98 _cleanup_free_ char *p = NULL;
104 r = fopen_temporary(fn, &f, &p);
108 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
109 (void) fchmod_umask(fileno(f), 0644);
111 r = write_string_stream_ts(f, line, flags, ts);
115 if (rename(p, fn) < 0) {
127 int write_string_file_ts(
130 WriteStringFileFlags flags,
131 struct timespec *ts) {
133 _cleanup_fclose_ FILE *f = NULL;
139 /* We don't know how to verify whether the file contents was already on-disk. */
140 assert(!((flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE) && (flags & WRITE_STRING_FILE_SYNC)));
142 if (flags & WRITE_STRING_FILE_ATOMIC) {
143 assert(flags & WRITE_STRING_FILE_CREATE);
145 r = write_string_file_atomic(fn, line, flags, ts);
153 if (flags & WRITE_STRING_FILE_CREATE) {
162 /* We manually build our own version of fopen(..., "we") that
163 * works without O_CREAT */
164 fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY);
170 f = fdopen(fd, "we");
178 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
180 if (flags & WRITE_STRING_FILE_DISABLE_BUFFER)
181 setvbuf(f, NULL, _IONBF, 0);
183 r = write_string_stream_ts(f, line, flags, ts);
190 if (!(flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE))
195 /* OK, the operation failed, but let's see if the right
196 * contents in place already. If so, eat up the error. */
198 q = verify_file(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
205 int read_one_line_file(const char *fn, char **line) {
206 _cleanup_fclose_ FILE *f = NULL;
216 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
218 r = read_line(f, LONG_LINE_MAX, line);
219 return r < 0 ? r : 0;
222 int verify_file(const char *fn, const char *blob, bool accept_extra_nl) {
223 _cleanup_fclose_ FILE *f = NULL;
224 _cleanup_free_ char *buf = NULL;
232 if (accept_extra_nl && endswith(blob, "\n"))
233 accept_extra_nl = false;
235 buf = malloc(l + accept_extra_nl + 1);
243 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
245 /* We try to read one byte more than we need, so that we know whether we hit eof */
247 k = fread(buf, 1, l + accept_extra_nl + 1, f);
249 return errno > 0 ? -errno : -EIO;
251 if (k != l && k != l + accept_extra_nl)
253 if (memcmp(buf, blob, l) != 0)
255 if (k > l && buf[l] != '\n')
261 int read_full_stream(FILE *f, char **contents, size_t *size) {
263 _cleanup_free_ char *buf = NULL;
269 if (fstat(fileno(f), &st) < 0)
274 if (S_ISREG(st.st_mode)) {
277 if (st.st_size > READ_FULL_BYTES_MAX)
280 /* Start with the right file size, but be prepared for files from /proc which generally report a file
281 * size of 0. Note that we increase the size to read here by one, so that the first read attempt
282 * already makes us notice the EOF. */
292 t = realloc(buf, n + 1);
298 k = fread(buf + l, 1, n - l, f);
303 return errno > 0 ? -errno : -EIO;
308 /* We aren't expecting fread() to return a short read outside
309 * of (error && eof), assert buffer is full and enlarge buffer.
314 if (n >= READ_FULL_BYTES_MAX)
317 n = MIN(n * 2, READ_FULL_BYTES_MAX);
322 buf = NULL; /* do not free */
330 int read_full_file(const char *fn, char **contents, size_t *size) {
331 _cleanup_fclose_ FILE *f = NULL;
340 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
342 return read_full_stream(f, contents, size);
345 static int parse_env_file_internal(
349 int (*push) (const char *filename, unsigned line,
350 const char *key, char *value, void *userdata, int *n_pushed),
354 _cleanup_free_ char *contents = NULL, *key = NULL;
355 size_t key_alloc = 0, n_key = 0, value_alloc = 0, n_value = 0, last_value_whitespace = (size_t) -1, last_key_whitespace = (size_t) -1;
356 char *p, *value = NULL;
367 SINGLE_QUOTE_VALUE_ESCAPE,
369 DOUBLE_QUOTE_VALUE_ESCAPE,
377 r = read_full_stream(f, &contents, NULL);
379 r = read_full_file(fname, &contents, NULL);
383 for (p = contents; *p; p++) {
389 if (strchr(COMMENTS, c))
391 else if (!strchr(WHITESPACE, c)) {
393 last_key_whitespace = (size_t) -1;
395 if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
405 if (strchr(newline, c)) {
409 } else if (c == '=') {
411 last_value_whitespace = (size_t) -1;
413 if (!strchr(WHITESPACE, c))
414 last_key_whitespace = (size_t) -1;
415 else if (last_key_whitespace == (size_t) -1)
416 last_key_whitespace = n_key;
418 if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
429 if (strchr(newline, c)) {
437 /* strip trailing whitespace from key */
438 if (last_key_whitespace != (size_t) -1)
439 key[last_key_whitespace] = 0;
441 r = push(fname, line, key, value, userdata, n_pushed);
447 value_alloc = n_value = 0;
449 } else if (c == '\'')
450 state = SINGLE_QUOTE_VALUE;
452 state = DOUBLE_QUOTE_VALUE;
454 state = VALUE_ESCAPE;
455 else if (!strchr(WHITESPACE, c)) {
458 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
463 value[n_value++] = c;
469 if (strchr(newline, c)) {
478 /* Chomp off trailing whitespace from value */
479 if (last_value_whitespace != (size_t) -1)
480 value[last_value_whitespace] = 0;
482 /* strip trailing whitespace from key */
483 if (last_key_whitespace != (size_t) -1)
484 key[last_key_whitespace] = 0;
486 r = push(fname, line, key, value, userdata, n_pushed);
492 value_alloc = n_value = 0;
494 } else if (c == '\\') {
495 state = VALUE_ESCAPE;
496 last_value_whitespace = (size_t) -1;
498 if (!strchr(WHITESPACE, c))
499 last_value_whitespace = (size_t) -1;
500 else if (last_value_whitespace == (size_t) -1)
501 last_value_whitespace = n_value;
503 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
508 value[n_value++] = c;
516 if (!strchr(newline, c)) {
517 /* Escaped newlines we eat up entirely */
518 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
523 value[n_value++] = c;
527 case SINGLE_QUOTE_VALUE:
531 state = SINGLE_QUOTE_VALUE_ESCAPE;
533 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
538 value[n_value++] = c;
543 case SINGLE_QUOTE_VALUE_ESCAPE:
544 state = SINGLE_QUOTE_VALUE;
546 if (!strchr(newline, c)) {
547 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
552 value[n_value++] = c;
556 case DOUBLE_QUOTE_VALUE:
560 state = DOUBLE_QUOTE_VALUE_ESCAPE;
562 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
567 value[n_value++] = c;
572 case DOUBLE_QUOTE_VALUE_ESCAPE:
573 state = DOUBLE_QUOTE_VALUE;
575 if (!strchr(newline, c)) {
576 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
581 value[n_value++] = c;
587 state = COMMENT_ESCAPE;
588 else if (strchr(newline, c)) {
605 SINGLE_QUOTE_VALUE_ESCAPE,
607 DOUBLE_QUOTE_VALUE_ESCAPE)) {
615 if (last_value_whitespace != (size_t) -1)
616 value[last_value_whitespace] = 0;
618 /* strip trailing whitespace from key */
619 if (last_key_whitespace != (size_t) -1)
620 key[last_key_whitespace] = 0;
622 r = push(fname, line, key, value, userdata, n_pushed);
634 static int check_utf8ness_and_warn(
635 const char *filename, unsigned line,
636 const char *key, char *value) {
638 if (!utf8_is_valid(key)) {
639 _cleanup_free_ char *p = NULL;
641 p = utf8_escape_invalid(key);
642 log_error("%s:%u: invalid UTF-8 in key '%s', ignoring.", strna(filename), line, p);
646 if (value && !utf8_is_valid(value)) {
647 _cleanup_free_ char *p = NULL;
649 p = utf8_escape_invalid(value);
650 log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, p);
657 static int parse_env_file_push(
658 const char *filename, unsigned line,
659 const char *key, char *value,
664 va_list aq, *ap = userdata;
667 r = check_utf8ness_and_warn(filename, line, key, value);
673 while ((k = va_arg(aq, const char *))) {
676 v = va_arg(aq, char **);
698 const char *newline, ...) {
706 va_start(ap, newline);
707 r = parse_env_file_internal(NULL, fname, newline, parse_env_file_push, &ap, &n_pushed);
710 return r < 0 ? r : n_pushed;
713 #if 0 /// UNNEEDED by elogind
714 static int load_env_file_push(
715 const char *filename, unsigned line,
716 const char *key, char *value,
719 char ***m = userdata;
723 r = check_utf8ness_and_warn(filename, line, key, value);
727 p = strjoin(key, "=", value);
731 r = strv_env_replace(m, p);
744 int load_env_file(FILE *f, const char *fname, const char *newline, char ***rl) {
751 r = parse_env_file_internal(f, fname, newline, load_env_file_push, &m, NULL);
762 static int load_env_file_push_pairs(
763 const char *filename, unsigned line,
764 const char *key, char *value,
767 char ***m = userdata;
770 r = check_utf8ness_and_warn(filename, line, key, value);
774 r = strv_extend(m, key);
779 r = strv_extend(m, "");
783 r = strv_push(m, value);
794 int load_env_file_pairs(FILE *f, const char *fname, const char *newline, char ***rl) {
801 r = parse_env_file_internal(f, fname, newline, load_env_file_push_pairs, &m, NULL);
810 #if 0 /// UNNEEDED by elogind
812 static int merge_env_file_push(
813 const char *filename, unsigned line,
814 const char *key, char *value,
818 char ***env = userdata;
819 char *expanded_value;
824 log_error("%s:%u: invalid syntax (around \"%s\"), ignoring.", strna(filename), line, key);
828 if (!env_name_is_valid(key)) {
829 log_error("%s:%u: invalid variable name \"%s\", ignoring.", strna(filename), line, key);
834 expanded_value = replace_env(value, *env,
835 REPLACE_ENV_USE_ENVIRONMENT|
836 REPLACE_ENV_ALLOW_BRACELESS|
837 REPLACE_ENV_ALLOW_EXTENDED);
841 free_and_replace(value, expanded_value);
843 return load_env_file_push(filename, line, key, value, env, n_pushed);
851 /* NOTE: this function supports braceful and braceless variable expansions,
852 * plus "extended" substitutions, unlike other exported parsing functions.
855 return parse_env_file_internal(f, fname, NEWLINE, merge_env_file_push, env, NULL);
858 static void write_env_var(FILE *f, const char *v) {
864 fputs_unlocked(v, f);
865 fputc_unlocked('\n', f);
870 fwrite_unlocked(v, 1, p-v, f);
872 if (string_has_cc(p, NULL) || chars_intersect(p, WHITESPACE SHELL_NEED_QUOTES)) {
873 fputc_unlocked('\"', f);
876 if (strchr(SHELL_NEED_ESCAPE, *p))
877 fputc_unlocked('\\', f);
879 fputc_unlocked(*p, f);
882 fputc_unlocked('\"', f);
884 fputs_unlocked(p, f);
886 fputc_unlocked('\n', f);
889 int write_env_file(const char *fname, char **l) {
890 _cleanup_fclose_ FILE *f = NULL;
891 _cleanup_free_ char *p = NULL;
897 r = fopen_temporary(fname, &f, &p);
901 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
902 (void) fchmod_umask(fileno(f), 0644);
905 write_env_var(f, *i);
907 r = fflush_and_check(f);
909 if (rename(p, fname) >= 0)
919 int executable_is_script(const char *path, char **interpreter) {
921 _cleanup_free_ char *line = NULL;
927 r = read_one_line_file(path, &line);
931 if (!startswith(line, "#!"))
934 ans = strstrip(line + 2);
935 len = strcspn(ans, " \t");
940 ans = strndup(ans, len);
950 * Retrieve one field from a file like /proc/self/status. pattern
951 * should not include whitespace or the delimiter (':'). pattern matches only
952 * the beginning of a line. Whitespace before ':' is skipped. Whitespace and
953 * zeros after the ':' will be skipped. field must be freed afterwards.
954 * terminator specifies the terminating characters of the field value (not
955 * included in the value).
957 int get_proc_field(const char *filename, const char *pattern, const char *terminator, char **field) {
958 _cleanup_free_ char *status = NULL;
968 r = read_full_file(filename, &status, NULL);
978 t = strstr(t, pattern);
982 /* Check that pattern occurs in beginning of line. */
983 pattern_ok = (t == status || t[-1] == '\n');
985 t += strlen(pattern);
987 } while (!pattern_ok);
989 t += strspn(t, " \t");
998 t += strspn(t, " \t");
1000 /* Also skip zeros, because when this is used for
1001 * capabilities, we don't want the zeros. This way the
1002 * same capability set always maps to the same string,
1003 * irrespective of the total capability set size. For
1004 * other numbers it shouldn't matter. */
1005 t += strspn(t, "0");
1006 /* Back off one char if there's nothing but whitespace
1008 if (!*t || isspace(*t))
1012 len = strcspn(t, terminator);
1014 f = strndup(t, len);
1022 DIR *xopendirat(int fd, const char *name, int flags) {
1026 assert(!(flags & O_CREAT));
1028 nfd = openat(fd, name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|flags, 0);
1041 #if 0 /// UNNEEDED by elogind
1042 static int search_and_fopen_internal(const char *path, const char *mode, const char *root, char **search, FILE **_f) {
1049 if (!path_strv_resolve_uniq(search, root))
1052 STRV_FOREACH(i, search) {
1053 _cleanup_free_ char *p = NULL;
1057 p = strjoin(root, *i, "/", path);
1059 p = strjoin(*i, "/", path);
1069 if (errno != ENOENT)
1076 int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **_f) {
1077 _cleanup_strv_free_ char **copy = NULL;
1083 if (path_is_absolute(path)) {
1086 f = fopen(path, mode);
1095 copy = strv_copy((char**) search);
1099 return search_and_fopen_internal(path, mode, root, copy, _f);
1102 int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **_f) {
1103 _cleanup_strv_free_ char **s = NULL;
1105 if (path_is_absolute(path)) {
1108 f = fopen(path, mode);
1117 s = strv_split_nulstr(search);
1121 return search_and_fopen_internal(path, mode, root, s, _f);
1125 int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
1134 r = tempfn_xxxxxx(path, NULL, &t);
1138 fd = mkostemp_safe(t);
1144 f = fdopen(fd, "we");
1158 int fflush_and_check(FILE *f) {
1165 return errno > 0 ? -errno : -EIO;
1170 int fflush_sync_and_check(FILE *f) {
1175 r = fflush_and_check(f);
1179 if (fsync(fileno(f)) < 0)
1185 /* This is much like mkostemp() but is subject to umask(). */
1186 int mkostemp_safe(char *pattern) {
1187 _cleanup_umask_ mode_t u = 0;
1194 fd = mkostemp(pattern, O_CLOEXEC);
1201 int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
1213 * /foo/bar/.#<extra>waldoXXXXXX
1217 if (!filename_is_valid(fn))
1223 t = new(char, strlen(p) + 2 + strlen(extra) + 6 + 1);
1227 strcpy(stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn), "XXXXXX");
1229 *ret = path_kill_slashes(t);
1233 int tempfn_random(const char *p, const char *extra, char **ret) {
1247 * /foo/bar/.#<extra>waldobaa2a261115984a9
1251 if (!filename_is_valid(fn))
1257 t = new(char, strlen(p) + 2 + strlen(extra) + 16 + 1);
1261 x = stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn);
1264 for (i = 0; i < 16; i++) {
1265 *(x++) = hexchar(u & 0xF);
1271 *ret = path_kill_slashes(t);
1275 #if 0 /// UNNEEDED by elogind
1276 int tempfn_random_child(const char *p, const char *extra, char **ret) {
1287 * /foo/bar/waldo/.#<extra>3c2b6219aa75d7d0
1299 t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1);
1303 x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra);
1306 for (i = 0; i < 16; i++) {
1307 *(x++) = hexchar(u & 0xF);
1313 *ret = path_kill_slashes(t);
1317 int write_timestamp_file_atomic(const char *fn, usec_t n) {
1318 char ln[DECIMAL_STR_MAX(n)+2];
1320 /* Creates a "timestamp" file, that contains nothing but a
1321 * usec_t timestamp, formatted in ASCII. */
1323 if (n <= 0 || n >= USEC_INFINITY)
1326 xsprintf(ln, USEC_FMT "\n", n);
1328 return write_string_file(fn, ln, WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
1331 int read_timestamp_file(const char *fn, usec_t *ret) {
1332 _cleanup_free_ char *ln = NULL;
1336 r = read_one_line_file(fn, &ln);
1340 r = safe_atou64(ln, &t);
1344 if (t <= 0 || t >= (uint64_t) USEC_INFINITY)
1351 int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space) {
1356 /* Outputs the specified string with fputs(), but optionally prefixes it with a separator. The *space parameter
1357 * when specified shall initially point to a boolean variable initialized to false. It is set to true after the
1358 * first invocation. This call is supposed to be use in loops, where a separator shall be inserted between each
1359 * element, but not before the first one. */
1369 r = fputs(separator, f);
1381 int open_tmpfile_unlinkable(const char *directory, int flags) {
1386 r = tmp_dir(&directory);
1391 /* Returns an unlinked temporary file that cannot be linked into the file system anymore */
1393 /* Try O_TMPFILE first, if it is supported */
1394 fd = open(directory, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR);
1398 /* Fall back to unguessable name + unlinking */
1399 p = strjoina(directory, "/systemd-tmp-XXXXXX");
1401 fd = mkostemp_safe(p);
1410 #if 0 /// UNNEEDED by elogind
1411 int open_tmpfile_linkable(const char *target, int flags, char **ret_path) {
1412 _cleanup_free_ char *tmp = NULL;
1418 /* Don't allow O_EXCL, as that has a special meaning for O_TMPFILE */
1419 assert((flags & O_EXCL) == 0);
1421 /* Creates a temporary file, that shall be renamed to "target" later. If possible, this uses O_TMPFILE – in
1422 * which case "ret_path" will be returned as NULL. If not possible a the tempoary path name used is returned in
1423 * "ret_path". Use link_tmpfile() below to rename the result after writing the file in full. */
1426 _cleanup_free_ char *dn = NULL;
1428 dn = dirname_malloc(target);
1432 fd = open(dn, O_TMPFILE|flags, 0640);
1438 log_debug_errno(errno, "Failed to use O_TMPFILE on %s: %m", dn);
1441 r = tempfn_random(target, NULL, &tmp);
1445 fd = open(tmp, O_CREAT|O_EXCL|O_NOFOLLOW|O_NOCTTY|flags, 0640);
1456 int open_serialization_fd(const char *ident) {
1459 fd = memfd_create(ident, MFD_CLOEXEC);
1463 path = getpid_cached() == 1 ? "/run/systemd" : "/tmp";
1464 fd = open_tmpfile_unlinkable(path, O_RDWR|O_CLOEXEC);
1468 log_debug("Serializing %s to %s.", ident, path);
1470 log_debug("Serializing %s to memfd.", ident);
1475 #if 0 /// UNNEEDED by elogind
1476 int link_tmpfile(int fd, const char *path, const char *target) {
1481 /* Moves a temporary file created with open_tmpfile() above into its final place. if "path" is NULL an fd
1482 * created with O_TMPFILE is assumed, and linkat() is used. Otherwise it is assumed O_TMPFILE is not supported
1483 * on the directory, and renameat2() is used instead.
1485 * Note that in both cases we will not replace existing files. This is because linkat() does not support this
1486 * operation currently (renameat2() does), and there is no nice way to emulate this. */
1489 if (rename_noreplace(AT_FDCWD, path, AT_FDCWD, target) < 0)
1492 char proc_fd_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(fd) + 1];
1494 xsprintf(proc_fd_path, "/proc/self/fd/%i", fd);
1496 if (linkat(AT_FDCWD, proc_fd_path, AT_FDCWD, target, AT_SYMLINK_FOLLOW) < 0)
1503 int read_nul_string(FILE *f, char **ret) {
1504 _cleanup_free_ char *x = NULL;
1505 size_t allocated = 0, n = 0;
1510 /* Reads a NUL-terminated string from the specified file. */
1515 if (!GREEDY_REALLOC(x, allocated, n+2))
1519 if (c == 0) /* Terminate at NUL byte */
1524 break; /* Terminate at EOF */
1544 int mkdtemp_malloc(const char *template, char **ret) {
1550 p = strdup(template);
1564 DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, funlockfile);
1566 int read_line(FILE *f, size_t limit, char **ret) {
1567 _cleanup_free_ char *buffer = NULL;
1568 size_t n = 0, allocated = 0, count = 0;
1572 /* Something like a bounded version of getline().
1574 * Considers EOF, \n and \0 end of line delimiters, and does not include these delimiters in the string
1577 * Returns the number of bytes read from the files (i.e. including delimiters — this hence usually differs from
1578 * the number of characters in the returned string). When EOF is hit, 0 is returned.
1580 * The input parameter limit is the maximum numbers of characters in the returned string, i.e. excluding
1581 * delimiters. If the limit is hit we fail and return -ENOBUFS.
1583 * If a line shall be skipped ret may be initialized as NULL. */
1586 if (!GREEDY_REALLOC(buffer, allocated, 1))
1591 _unused_ _cleanup_(funlockfilep) FILE *flocked = f;
1601 c = fgetc_unlocked(f);
1603 /* if we read an error, and have no data to return, then propagate the error */
1604 if (ferror_unlocked(f) && n == 0)
1605 return errno > 0 ? -errno : -EIO;
1612 if (IN_SET(c, '\n', 0)) /* Reached a delimiter */
1616 if (!GREEDY_REALLOC(buffer, allocated, n + 2))
1619 buffer[n] = (char) c;