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) {
69 if (!(flags & WRITE_STRING_FILE_AVOID_NEWLINE) && !endswith(line, "\n"))
73 struct timespec twice[2] = {*ts, *ts};
75 if (futimens(fileno(f), twice) < 0)
79 if (flags & WRITE_STRING_FILE_SYNC)
80 return fflush_sync_and_check(f);
82 return fflush_and_check(f);
85 static int write_string_file_atomic(
88 WriteStringFileFlags flags,
89 struct timespec *ts) {
91 _cleanup_fclose_ FILE *f = NULL;
92 _cleanup_free_ char *p = NULL;
98 r = fopen_temporary(fn, &f, &p);
102 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
103 (void) fchmod_umask(fileno(f), 0644);
105 r = write_string_stream_ts(f, line, flags, ts);
109 if (rename(p, fn) < 0) {
121 int write_string_file_ts(
124 WriteStringFileFlags flags,
125 struct timespec *ts) {
127 _cleanup_fclose_ FILE *f = NULL;
133 /* We don't know how to verify whether the file contents was already on-disk. */
134 assert(!((flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE) && (flags & WRITE_STRING_FILE_SYNC)));
136 if (flags & WRITE_STRING_FILE_ATOMIC) {
137 assert(flags & WRITE_STRING_FILE_CREATE);
139 r = write_string_file_atomic(fn, line, flags, ts);
147 if (flags & WRITE_STRING_FILE_CREATE) {
156 /* We manually build our own version of fopen(..., "we") that
157 * works without O_CREAT */
158 fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY);
164 f = fdopen(fd, "we");
172 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
174 if (flags & WRITE_STRING_FILE_DISABLE_BUFFER)
175 setvbuf(f, NULL, _IONBF, 0);
177 r = write_string_stream_ts(f, line, flags, ts);
184 if (!(flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE))
189 /* OK, the operation failed, but let's see if the right
190 * contents in place already. If so, eat up the error. */
192 q = verify_file(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
199 int read_one_line_file(const char *fn, char **line) {
200 _cleanup_fclose_ FILE *f = NULL;
210 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
212 r = read_line(f, LONG_LINE_MAX, line);
213 return r < 0 ? r : 0;
216 int verify_file(const char *fn, const char *blob, bool accept_extra_nl) {
217 _cleanup_fclose_ FILE *f = NULL;
218 _cleanup_free_ char *buf = NULL;
226 if (accept_extra_nl && endswith(blob, "\n"))
227 accept_extra_nl = false;
229 buf = malloc(l + accept_extra_nl + 1);
237 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
239 /* We try to read one byte more than we need, so that we know whether we hit eof */
241 k = fread(buf, 1, l + accept_extra_nl + 1, f);
243 return errno > 0 ? -errno : -EIO;
245 if (k != l && k != l + accept_extra_nl)
247 if (memcmp(buf, blob, l) != 0)
249 if (k > l && buf[l] != '\n')
255 int read_full_stream(FILE *f, char **contents, size_t *size) {
257 _cleanup_free_ char *buf = NULL;
263 if (fstat(fileno(f), &st) < 0)
268 if (S_ISREG(st.st_mode)) {
271 if (st.st_size > READ_FULL_BYTES_MAX)
274 /* Start with the right file size, but be prepared for files from /proc which generally report a file
275 * size of 0. Note that we increase the size to read here by one, so that the first read attempt
276 * already makes us notice the EOF. */
286 t = realloc(buf, n + 1);
292 k = fread(buf + l, 1, n - l, f);
297 return errno > 0 ? -errno : -EIO;
302 /* We aren't expecting fread() to return a short read outside
303 * of (error && eof), assert buffer is full and enlarge buffer.
308 if (n >= READ_FULL_BYTES_MAX)
311 n = MIN(n * 2, READ_FULL_BYTES_MAX);
316 buf = NULL; /* do not free */
324 int read_full_file(const char *fn, char **contents, size_t *size) {
325 _cleanup_fclose_ FILE *f = NULL;
334 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
336 return read_full_stream(f, contents, size);
339 static int parse_env_file_internal(
343 int (*push) (const char *filename, unsigned line,
344 const char *key, char *value, void *userdata, int *n_pushed),
348 _cleanup_free_ char *contents = NULL, *key = NULL;
349 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;
350 char *p, *value = NULL;
361 SINGLE_QUOTE_VALUE_ESCAPE,
363 DOUBLE_QUOTE_VALUE_ESCAPE,
371 r = read_full_stream(f, &contents, NULL);
373 r = read_full_file(fname, &contents, NULL);
377 for (p = contents; *p; p++) {
383 if (strchr(COMMENTS, c))
385 else if (!strchr(WHITESPACE, c)) {
387 last_key_whitespace = (size_t) -1;
389 if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
399 if (strchr(newline, c)) {
403 } else if (c == '=') {
405 last_value_whitespace = (size_t) -1;
407 if (!strchr(WHITESPACE, c))
408 last_key_whitespace = (size_t) -1;
409 else if (last_key_whitespace == (size_t) -1)
410 last_key_whitespace = n_key;
412 if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
423 if (strchr(newline, c)) {
431 /* strip trailing whitespace from key */
432 if (last_key_whitespace != (size_t) -1)
433 key[last_key_whitespace] = 0;
435 r = push(fname, line, key, value, userdata, n_pushed);
441 value_alloc = n_value = 0;
443 } else if (c == '\'')
444 state = SINGLE_QUOTE_VALUE;
446 state = DOUBLE_QUOTE_VALUE;
448 state = VALUE_ESCAPE;
449 else if (!strchr(WHITESPACE, c)) {
452 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
457 value[n_value++] = c;
463 if (strchr(newline, c)) {
472 /* Chomp off trailing whitespace from value */
473 if (last_value_whitespace != (size_t) -1)
474 value[last_value_whitespace] = 0;
476 /* strip trailing whitespace from key */
477 if (last_key_whitespace != (size_t) -1)
478 key[last_key_whitespace] = 0;
480 r = push(fname, line, key, value, userdata, n_pushed);
486 value_alloc = n_value = 0;
488 } else if (c == '\\') {
489 state = VALUE_ESCAPE;
490 last_value_whitespace = (size_t) -1;
492 if (!strchr(WHITESPACE, c))
493 last_value_whitespace = (size_t) -1;
494 else if (last_value_whitespace == (size_t) -1)
495 last_value_whitespace = n_value;
497 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
502 value[n_value++] = c;
510 if (!strchr(newline, c)) {
511 /* Escaped newlines we eat up entirely */
512 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
517 value[n_value++] = c;
521 case SINGLE_QUOTE_VALUE:
525 state = SINGLE_QUOTE_VALUE_ESCAPE;
527 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
532 value[n_value++] = c;
537 case SINGLE_QUOTE_VALUE_ESCAPE:
538 state = SINGLE_QUOTE_VALUE;
540 if (!strchr(newline, c)) {
541 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
546 value[n_value++] = c;
550 case DOUBLE_QUOTE_VALUE:
554 state = DOUBLE_QUOTE_VALUE_ESCAPE;
556 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
561 value[n_value++] = c;
566 case DOUBLE_QUOTE_VALUE_ESCAPE:
567 state = DOUBLE_QUOTE_VALUE;
569 if (!strchr(newline, c)) {
570 if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
575 value[n_value++] = c;
581 state = COMMENT_ESCAPE;
582 else if (strchr(newline, c)) {
599 SINGLE_QUOTE_VALUE_ESCAPE,
601 DOUBLE_QUOTE_VALUE_ESCAPE)) {
609 if (last_value_whitespace != (size_t) -1)
610 value[last_value_whitespace] = 0;
612 /* strip trailing whitespace from key */
613 if (last_key_whitespace != (size_t) -1)
614 key[last_key_whitespace] = 0;
616 r = push(fname, line, key, value, userdata, n_pushed);
628 static int check_utf8ness_and_warn(
629 const char *filename, unsigned line,
630 const char *key, char *value) {
632 if (!utf8_is_valid(key)) {
633 _cleanup_free_ char *p = NULL;
635 p = utf8_escape_invalid(key);
636 log_error("%s:%u: invalid UTF-8 in key '%s', ignoring.", strna(filename), line, p);
640 if (value && !utf8_is_valid(value)) {
641 _cleanup_free_ char *p = NULL;
643 p = utf8_escape_invalid(value);
644 log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, p);
651 static int parse_env_file_push(
652 const char *filename, unsigned line,
653 const char *key, char *value,
658 va_list aq, *ap = userdata;
661 r = check_utf8ness_and_warn(filename, line, key, value);
667 while ((k = va_arg(aq, const char *))) {
670 v = va_arg(aq, char **);
692 const char *newline, ...) {
700 va_start(ap, newline);
701 r = parse_env_file_internal(NULL, fname, newline, parse_env_file_push, &ap, &n_pushed);
704 return r < 0 ? r : n_pushed;
707 #if 0 /// UNNEEDED by elogind
708 static int load_env_file_push(
709 const char *filename, unsigned line,
710 const char *key, char *value,
713 char ***m = userdata;
717 r = check_utf8ness_and_warn(filename, line, key, value);
721 p = strjoin(key, "=", value);
725 r = strv_env_replace(m, p);
738 int load_env_file(FILE *f, const char *fname, const char *newline, char ***rl) {
745 r = parse_env_file_internal(f, fname, newline, load_env_file_push, &m, NULL);
756 static int load_env_file_push_pairs(
757 const char *filename, unsigned line,
758 const char *key, char *value,
761 char ***m = userdata;
764 r = check_utf8ness_and_warn(filename, line, key, value);
768 r = strv_extend(m, key);
773 r = strv_extend(m, "");
777 r = strv_push(m, value);
788 int load_env_file_pairs(FILE *f, const char *fname, const char *newline, char ***rl) {
795 r = parse_env_file_internal(f, fname, newline, load_env_file_push_pairs, &m, NULL);
804 #if 0 /// UNNEEDED by elogind
806 static int merge_env_file_push(
807 const char *filename, unsigned line,
808 const char *key, char *value,
812 char ***env = userdata;
813 char *expanded_value;
818 log_error("%s:%u: invalid syntax (around \"%s\"), ignoring.", strna(filename), line, key);
822 if (!env_name_is_valid(key)) {
823 log_error("%s:%u: invalid variable name \"%s\", ignoring.", strna(filename), line, key);
828 expanded_value = replace_env(value, *env,
829 REPLACE_ENV_USE_ENVIRONMENT|
830 REPLACE_ENV_ALLOW_BRACELESS|
831 REPLACE_ENV_ALLOW_EXTENDED);
835 free_and_replace(value, expanded_value);
837 return load_env_file_push(filename, line, key, value, env, n_pushed);
845 /* NOTE: this function supports braceful and braceless variable expansions,
846 * plus "extended" substitutions, unlike other exported parsing functions.
849 return parse_env_file_internal(f, fname, NEWLINE, merge_env_file_push, env, NULL);
852 static void write_env_var(FILE *f, const char *v) {
858 fputs_unlocked(v, f);
859 fputc_unlocked('\n', f);
864 fwrite_unlocked(v, 1, p-v, f);
866 if (string_has_cc(p, NULL) || chars_intersect(p, WHITESPACE SHELL_NEED_QUOTES)) {
867 fputc_unlocked('\"', f);
870 if (strchr(SHELL_NEED_ESCAPE, *p))
871 fputc_unlocked('\\', f);
873 fputc_unlocked(*p, f);
876 fputc_unlocked('\"', f);
878 fputs_unlocked(p, f);
880 fputc_unlocked('\n', f);
883 int write_env_file(const char *fname, char **l) {
884 _cleanup_fclose_ FILE *f = NULL;
885 _cleanup_free_ char *p = NULL;
891 r = fopen_temporary(fname, &f, &p);
895 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
896 (void) fchmod_umask(fileno(f), 0644);
899 write_env_var(f, *i);
901 r = fflush_and_check(f);
903 if (rename(p, fname) >= 0)
913 int executable_is_script(const char *path, char **interpreter) {
915 _cleanup_free_ char *line = NULL;
921 r = read_one_line_file(path, &line);
925 if (!startswith(line, "#!"))
928 ans = strstrip(line + 2);
929 len = strcspn(ans, " \t");
934 ans = strndup(ans, len);
944 * Retrieve one field from a file like /proc/self/status. pattern
945 * should not include whitespace or the delimiter (':'). pattern matches only
946 * the beginning of a line. Whitespace before ':' is skipped. Whitespace and
947 * zeros after the ':' will be skipped. field must be freed afterwards.
948 * terminator specifies the terminating characters of the field value (not
949 * included in the value).
951 int get_proc_field(const char *filename, const char *pattern, const char *terminator, char **field) {
952 _cleanup_free_ char *status = NULL;
962 r = read_full_file(filename, &status, NULL);
972 t = strstr(t, pattern);
976 /* Check that pattern occurs in beginning of line. */
977 pattern_ok = (t == status || t[-1] == '\n');
979 t += strlen(pattern);
981 } while (!pattern_ok);
983 t += strspn(t, " \t");
992 t += strspn(t, " \t");
994 /* Also skip zeros, because when this is used for
995 * capabilities, we don't want the zeros. This way the
996 * same capability set always maps to the same string,
997 * irrespective of the total capability set size. For
998 * other numbers it shouldn't matter. */
1000 /* Back off one char if there's nothing but whitespace
1002 if (!*t || isspace(*t))
1006 len = strcspn(t, terminator);
1008 f = strndup(t, len);
1016 DIR *xopendirat(int fd, const char *name, int flags) {
1020 assert(!(flags & O_CREAT));
1022 nfd = openat(fd, name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|flags, 0);
1035 #if 0 /// UNNEEDED by elogind
1036 static int search_and_fopen_internal(const char *path, const char *mode, const char *root, char **search, FILE **_f) {
1043 if (!path_strv_resolve_uniq(search, root))
1046 STRV_FOREACH(i, search) {
1047 _cleanup_free_ char *p = NULL;
1051 p = strjoin(root, *i, "/", path);
1053 p = strjoin(*i, "/", path);
1063 if (errno != ENOENT)
1070 int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **_f) {
1071 _cleanup_strv_free_ char **copy = NULL;
1077 if (path_is_absolute(path)) {
1080 f = fopen(path, mode);
1089 copy = strv_copy((char**) search);
1093 return search_and_fopen_internal(path, mode, root, copy, _f);
1096 int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **_f) {
1097 _cleanup_strv_free_ char **s = NULL;
1099 if (path_is_absolute(path)) {
1102 f = fopen(path, mode);
1111 s = strv_split_nulstr(search);
1115 return search_and_fopen_internal(path, mode, root, s, _f);
1119 int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
1128 r = tempfn_xxxxxx(path, NULL, &t);
1132 fd = mkostemp_safe(t);
1138 f = fdopen(fd, "we");
1152 int fflush_and_check(FILE *f) {
1159 return errno > 0 ? -errno : -EIO;
1164 int fflush_sync_and_check(FILE *f) {
1169 r = fflush_and_check(f);
1173 if (fsync(fileno(f)) < 0)
1179 /* This is much like mkostemp() but is subject to umask(). */
1180 int mkostemp_safe(char *pattern) {
1181 _cleanup_umask_ mode_t u = 0;
1188 fd = mkostemp(pattern, O_CLOEXEC);
1195 int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
1207 * /foo/bar/.#<extra>waldoXXXXXX
1211 if (!filename_is_valid(fn))
1217 t = new(char, strlen(p) + 2 + strlen(extra) + 6 + 1);
1221 strcpy(stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn), "XXXXXX");
1223 *ret = path_kill_slashes(t);
1227 int tempfn_random(const char *p, const char *extra, char **ret) {
1241 * /foo/bar/.#<extra>waldobaa2a261115984a9
1245 if (!filename_is_valid(fn))
1251 t = new(char, strlen(p) + 2 + strlen(extra) + 16 + 1);
1255 x = stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn);
1258 for (i = 0; i < 16; i++) {
1259 *(x++) = hexchar(u & 0xF);
1265 *ret = path_kill_slashes(t);
1269 #if 0 /// UNNEEDED by elogind
1270 int tempfn_random_child(const char *p, const char *extra, char **ret) {
1281 * /foo/bar/waldo/.#<extra>3c2b6219aa75d7d0
1293 t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1);
1297 x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra);
1300 for (i = 0; i < 16; i++) {
1301 *(x++) = hexchar(u & 0xF);
1307 *ret = path_kill_slashes(t);
1311 int write_timestamp_file_atomic(const char *fn, usec_t n) {
1312 char ln[DECIMAL_STR_MAX(n)+2];
1314 /* Creates a "timestamp" file, that contains nothing but a
1315 * usec_t timestamp, formatted in ASCII. */
1317 if (n <= 0 || n >= USEC_INFINITY)
1320 xsprintf(ln, USEC_FMT "\n", n);
1322 return write_string_file(fn, ln, WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
1325 int read_timestamp_file(const char *fn, usec_t *ret) {
1326 _cleanup_free_ char *ln = NULL;
1330 r = read_one_line_file(fn, &ln);
1334 r = safe_atou64(ln, &t);
1338 if (t <= 0 || t >= (uint64_t) USEC_INFINITY)
1345 int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space) {
1350 /* Outputs the specified string with fputs(), but optionally prefixes it with a separator. The *space parameter
1351 * when specified shall initially point to a boolean variable initialized to false. It is set to true after the
1352 * first invocation. This call is supposed to be use in loops, where a separator shall be inserted between each
1353 * element, but not before the first one. */
1363 r = fputs(separator, f);
1375 int open_tmpfile_unlinkable(const char *directory, int flags) {
1380 r = tmp_dir(&directory);
1385 /* Returns an unlinked temporary file that cannot be linked into the file system anymore */
1387 /* Try O_TMPFILE first, if it is supported */
1388 fd = open(directory, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR);
1392 /* Fall back to unguessable name + unlinking */
1393 p = strjoina(directory, "/systemd-tmp-XXXXXX");
1395 fd = mkostemp_safe(p);
1404 #if 0 /// UNNEEDED by elogind
1405 int open_tmpfile_linkable(const char *target, int flags, char **ret_path) {
1406 _cleanup_free_ char *tmp = NULL;
1412 /* Don't allow O_EXCL, as that has a special meaning for O_TMPFILE */
1413 assert((flags & O_EXCL) == 0);
1415 /* Creates a temporary file, that shall be renamed to "target" later. If possible, this uses O_TMPFILE – in
1416 * which case "ret_path" will be returned as NULL. If not possible a the tempoary path name used is returned in
1417 * "ret_path". Use link_tmpfile() below to rename the result after writing the file in full. */
1420 _cleanup_free_ char *dn = NULL;
1422 dn = dirname_malloc(target);
1426 fd = open(dn, O_TMPFILE|flags, 0640);
1432 log_debug_errno(errno, "Failed to use O_TMPFILE on %s: %m", dn);
1435 r = tempfn_random(target, NULL, &tmp);
1439 fd = open(tmp, O_CREAT|O_EXCL|O_NOFOLLOW|O_NOCTTY|flags, 0640);
1450 int open_serialization_fd(const char *ident) {
1453 fd = memfd_create(ident, MFD_CLOEXEC);
1457 path = getpid_cached() == 1 ? "/run/systemd" : "/tmp";
1458 fd = open_tmpfile_unlinkable(path, O_RDWR|O_CLOEXEC);
1462 log_debug("Serializing %s to %s.", ident, path);
1464 log_debug("Serializing %s to memfd.", ident);
1469 #if 0 /// UNNEEDED by elogind
1470 int link_tmpfile(int fd, const char *path, const char *target) {
1475 /* Moves a temporary file created with open_tmpfile() above into its final place. if "path" is NULL an fd
1476 * created with O_TMPFILE is assumed, and linkat() is used. Otherwise it is assumed O_TMPFILE is not supported
1477 * on the directory, and renameat2() is used instead.
1479 * Note that in both cases we will not replace existing files. This is because linkat() does not support this
1480 * operation currently (renameat2() does), and there is no nice way to emulate this. */
1483 if (rename_noreplace(AT_FDCWD, path, AT_FDCWD, target) < 0)
1486 char proc_fd_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(fd) + 1];
1488 xsprintf(proc_fd_path, "/proc/self/fd/%i", fd);
1490 if (linkat(AT_FDCWD, proc_fd_path, AT_FDCWD, target, AT_SYMLINK_FOLLOW) < 0)
1497 int read_nul_string(FILE *f, char **ret) {
1498 _cleanup_free_ char *x = NULL;
1499 size_t allocated = 0, n = 0;
1504 /* Reads a NUL-terminated string from the specified file. */
1509 if (!GREEDY_REALLOC(x, allocated, n+2))
1513 if (c == 0) /* Terminate at NUL byte */
1518 break; /* Terminate at EOF */
1538 int mkdtemp_malloc(const char *template, char **ret) {
1544 p = strdup(template);
1558 DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, funlockfile);
1560 int read_line(FILE *f, size_t limit, char **ret) {
1561 _cleanup_free_ char *buffer = NULL;
1562 size_t n = 0, allocated = 0, count = 0;
1566 /* Something like a bounded version of getline().
1568 * Considers EOF, \n and \0 end of line delimiters, and does not include these delimiters in the string
1571 * Returns the number of bytes read from the files (i.e. including delimiters — this hence usually differs from
1572 * the number of characters in the returned string). When EOF is hit, 0 is returned.
1574 * The input parameter limit is the maximum numbers of characters in the returned string, i.e. excluding
1575 * delimiters. If the limit is hit we fail and return -ENOBUFS.
1577 * If a line shall be skipped ret may be initialized as NULL. */
1580 if (!GREEDY_REALLOC(buffer, allocated, 1))
1585 _unused_ _cleanup_(funlockfilep) FILE *flocked = f;
1595 c = fgetc_unlocked(f);
1597 /* if we read an error, and have no data to return, then propagate the error */
1598 if (ferror_unlocked(f) && n == 0)
1599 return errno > 0 ? -errno : -EIO;
1606 if (IN_SET(c, '\n', 0)) /* Reached a delimiter */
1610 if (!GREEDY_REALLOC(buffer, allocated, n + 2))
1613 buffer[n] = (char) c;