1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 This file is part of systemd.
5 Copyright 2010 Lennart Poettering
13 #include <stdio_ext.h>
18 #include <sys/types.h>
21 #include "alloc-util.h"
29 #include "hexdecoct.h"
33 #include "parse-util.h"
34 #include "path-util.h"
35 #include "process-util.h"
36 #include "random-util.h"
37 #include "stdio-util.h"
38 #include "string-util.h"
40 //#include "time-util.h"
41 #include "umask-util.h"
44 #define READ_FULL_BYTES_MAX (4U*1024U*1024U)
46 int write_string_stream_ts(
49 WriteStringFileFlags flags,
50 struct timespec *ts) {
61 needs_nl = !(flags & WRITE_STRING_FILE_AVOID_NEWLINE) && !endswith(line, "\n");
63 if (needs_nl && (flags & WRITE_STRING_FILE_DISABLE_BUFFER)) {
64 /* If STDIO buffering was disabled, then let's append the newline character to the string itself, so
65 * that the write goes out in one go, instead of two */
67 line = strjoina(line, "\n");
71 if (fputs(line, f) == EOF)
75 if (fputc('\n', f) == EOF)
78 if (flags & WRITE_STRING_FILE_SYNC)
79 r = fflush_sync_and_check(f);
81 r = fflush_and_check(f);
86 struct timespec twice[2] = {*ts, *ts};
88 if (futimens(fileno(f), twice) < 0)
95 static int write_string_file_atomic(
98 WriteStringFileFlags flags,
99 struct timespec *ts) {
101 _cleanup_fclose_ FILE *f = NULL;
102 _cleanup_free_ char *p = NULL;
108 r = fopen_temporary(fn, &f, &p);
112 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
113 (void) fchmod_umask(fileno(f), 0644);
115 r = write_string_stream_ts(f, line, flags, ts);
119 if (rename(p, fn) < 0) {
131 int write_string_file_ts(
134 WriteStringFileFlags flags,
135 struct timespec *ts) {
137 _cleanup_fclose_ FILE *f = NULL;
143 /* We don't know how to verify whether the file contents was already on-disk. */
144 assert(!((flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE) && (flags & WRITE_STRING_FILE_SYNC)));
146 if (flags & WRITE_STRING_FILE_ATOMIC) {
147 assert(flags & WRITE_STRING_FILE_CREATE);
149 r = write_string_file_atomic(fn, line, flags, ts);
157 if (flags & WRITE_STRING_FILE_CREATE) {
166 /* We manually build our own version of fopen(..., "we") that
167 * works without O_CREAT */
168 fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY);
174 f = fdopen(fd, "we");
182 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
184 if (flags & WRITE_STRING_FILE_DISABLE_BUFFER)
185 setvbuf(f, NULL, _IONBF, 0);
187 r = write_string_stream_ts(f, line, flags, ts);
194 if (!(flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE))
199 /* OK, the operation failed, but let's see if the right
200 * contents in place already. If so, eat up the error. */
202 q = verify_file(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
209 int read_one_line_file(const char *fn, char **line) {
210 _cleanup_fclose_ FILE *f = NULL;
220 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
222 r = read_line(f, LONG_LINE_MAX, line);
223 return r < 0 ? r : 0;
226 int verify_file(const char *fn, const char *blob, bool accept_extra_nl) {
227 _cleanup_fclose_ FILE *f = NULL;
228 _cleanup_free_ char *buf = NULL;
236 if (accept_extra_nl && endswith(blob, "\n"))
237 accept_extra_nl = false;
239 buf = malloc(l + accept_extra_nl + 1);
247 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
249 /* We try to read one byte more than we need, so that we know whether we hit eof */
251 k = fread(buf, 1, l + accept_extra_nl + 1, f);
253 return errno > 0 ? -errno : -EIO;
255 if (k != l && k != l + accept_extra_nl)
257 if (memcmp(buf, blob, l) != 0)
259 if (k > l && buf[l] != '\n')
265 int read_full_stream(FILE *f, char **contents, size_t *size) {
267 _cleanup_free_ char *buf = NULL;
273 if (fstat(fileno(f), &st) < 0)
278 if (S_ISREG(st.st_mode)) {
281 if (st.st_size > READ_FULL_BYTES_MAX)
284 /* Start with the right file size, but be prepared for files from /proc which generally report a file
285 * size of 0. Note that we increase the size to read here by one, so that the first read attempt
286 * already makes us notice the EOF. */
296 t = realloc(buf, n + 1);
302 k = fread(buf + l, 1, n - l, f);
307 return errno > 0 ? -errno : -EIO;
312 /* We aren't expecting fread() to return a short read outside
313 * of (error && eof), assert buffer is full and enlarge buffer.
318 if (n >= READ_FULL_BYTES_MAX)
321 n = MIN(n * 2, READ_FULL_BYTES_MAX);
325 *contents = TAKE_PTR(buf);
333 int read_full_file(const char *fn, char **contents, size_t *size) {
334 _cleanup_fclose_ FILE *f = NULL;
343 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
345 return read_full_stream(f, contents, size);
348 static int parse_env_file_internal(
352 int (*push) (const char *filename, unsigned line,
353 const char *key, char *value, void *userdata, int *n_pushed),
357 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;
358 _cleanup_free_ char *contents = NULL, *key = NULL, *value = NULL;
370 SINGLE_QUOTE_VALUE_ESCAPE,
372 DOUBLE_QUOTE_VALUE_ESCAPE,
380 r = read_full_stream(f, &contents, NULL);
382 r = read_full_file(fname, &contents, NULL);
386 for (p = contents; *p; p++) {
392 if (strchr(COMMENTS, c))
394 else if (!strchr(WHITESPACE, c)) {
396 last_key_whitespace = (size_t) -1;
398 if (!GREEDY_REALLOC(key, key_alloc, n_key+2))
406 if (strchr(newline, c)) {
410 } else if (c == '=') {
412 last_value_whitespace = (size_t) -1;
414 if (!strchr(WHITESPACE, c))
415 last_key_whitespace = (size_t) -1;
416 else if (last_key_whitespace == (size_t) -1)
417 last_key_whitespace = n_key;
419 if (!GREEDY_REALLOC(key, key_alloc, n_key+2))
428 if (strchr(newline, c)) {
436 /* strip trailing whitespace from key */
437 if (last_key_whitespace != (size_t) -1)
438 key[last_key_whitespace] = 0;
440 r = push(fname, line, key, value, userdata, n_pushed);
446 value_alloc = n_value = 0;
448 } else if (c == '\'')
449 state = SINGLE_QUOTE_VALUE;
451 state = DOUBLE_QUOTE_VALUE;
453 state = VALUE_ESCAPE;
454 else if (!strchr(WHITESPACE, c)) {
457 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
460 value[n_value++] = c;
466 if (strchr(newline, c)) {
475 /* Chomp off trailing whitespace from value */
476 if (last_value_whitespace != (size_t) -1)
477 value[last_value_whitespace] = 0;
479 /* strip trailing whitespace from key */
480 if (last_key_whitespace != (size_t) -1)
481 key[last_key_whitespace] = 0;
483 r = push(fname, line, key, value, userdata, n_pushed);
489 value_alloc = n_value = 0;
491 } else if (c == '\\') {
492 state = VALUE_ESCAPE;
493 last_value_whitespace = (size_t) -1;
495 if (!strchr(WHITESPACE, c))
496 last_value_whitespace = (size_t) -1;
497 else if (last_value_whitespace == (size_t) -1)
498 last_value_whitespace = n_value;
500 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
503 value[n_value++] = c;
511 if (!strchr(newline, c)) {
512 /* Escaped newlines we eat up entirely */
513 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
516 value[n_value++] = c;
520 case SINGLE_QUOTE_VALUE:
524 state = SINGLE_QUOTE_VALUE_ESCAPE;
526 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
529 value[n_value++] = c;
534 case SINGLE_QUOTE_VALUE_ESCAPE:
535 state = SINGLE_QUOTE_VALUE;
537 if (!strchr(newline, c)) {
538 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
541 value[n_value++] = c;
545 case DOUBLE_QUOTE_VALUE:
549 state = DOUBLE_QUOTE_VALUE_ESCAPE;
551 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
554 value[n_value++] = c;
559 case DOUBLE_QUOTE_VALUE_ESCAPE:
560 state = DOUBLE_QUOTE_VALUE;
562 if (!strchr(newline, c)) {
563 if (!GREEDY_REALLOC(value, value_alloc, n_value+2))
566 value[n_value++] = c;
572 state = COMMENT_ESCAPE;
573 else if (strchr(newline, c)) {
590 SINGLE_QUOTE_VALUE_ESCAPE,
592 DOUBLE_QUOTE_VALUE_ESCAPE)) {
600 if (last_value_whitespace != (size_t) -1)
601 value[last_value_whitespace] = 0;
603 /* strip trailing whitespace from key */
604 if (last_key_whitespace != (size_t) -1)
605 key[last_key_whitespace] = 0;
607 r = push(fname, line, key, value, userdata, n_pushed);
617 static int check_utf8ness_and_warn(
618 const char *filename, unsigned line,
619 const char *key, char *value) {
621 if (!utf8_is_valid(key)) {
622 _cleanup_free_ char *p = NULL;
624 p = utf8_escape_invalid(key);
625 log_error("%s:%u: invalid UTF-8 in key '%s', ignoring.", strna(filename), line, p);
629 if (value && !utf8_is_valid(value)) {
630 _cleanup_free_ char *p = NULL;
632 p = utf8_escape_invalid(value);
633 log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, p);
640 static int parse_env_file_push(
641 const char *filename, unsigned line,
642 const char *key, char *value,
647 va_list aq, *ap = userdata;
650 r = check_utf8ness_and_warn(filename, line, key, value);
656 while ((k = va_arg(aq, const char *))) {
659 v = va_arg(aq, char **);
682 const char *newline, ...) {
690 va_start(ap, newline);
691 r = parse_env_file_internal(f, fname, newline, parse_env_file_push, &ap, &n_pushed);
694 return r < 0 ? r : n_pushed;
697 #if 0 /// UNNEEDED by elogind
698 static int load_env_file_push(
699 const char *filename, unsigned line,
700 const char *key, char *value,
703 char ***m = userdata;
707 r = check_utf8ness_and_warn(filename, line, key, value);
711 p = strjoin(key, "=", value);
715 r = strv_env_replace(m, p);
728 int load_env_file(FILE *f, const char *fname, const char *newline, char ***rl) {
735 r = parse_env_file_internal(f, fname, newline, load_env_file_push, &m, NULL);
746 static int load_env_file_push_pairs(
747 const char *filename, unsigned line,
748 const char *key, char *value,
751 char ***m = userdata;
754 r = check_utf8ness_and_warn(filename, line, key, value);
758 r = strv_extend(m, key);
763 r = strv_extend(m, "");
767 r = strv_push(m, value);
778 int load_env_file_pairs(FILE *f, const char *fname, const char *newline, char ***rl) {
785 r = parse_env_file_internal(f, fname, newline, load_env_file_push_pairs, &m, NULL);
794 #if 0 /// UNNEEDED by elogind
796 static int merge_env_file_push(
797 const char *filename, unsigned line,
798 const char *key, char *value,
802 char ***env = userdata;
803 char *expanded_value;
808 log_error("%s:%u: invalid syntax (around \"%s\"), ignoring.", strna(filename), line, key);
812 if (!env_name_is_valid(key)) {
813 log_error("%s:%u: invalid variable name \"%s\", ignoring.", strna(filename), line, key);
818 expanded_value = replace_env(value, *env,
819 REPLACE_ENV_USE_ENVIRONMENT|
820 REPLACE_ENV_ALLOW_BRACELESS|
821 REPLACE_ENV_ALLOW_EXTENDED);
825 free_and_replace(value, expanded_value);
827 return load_env_file_push(filename, line, key, value, env, n_pushed);
835 /* NOTE: this function supports braceful and braceless variable expansions,
836 * plus "extended" substitutions, unlike other exported parsing functions.
839 return parse_env_file_internal(f, fname, NEWLINE, merge_env_file_push, env, NULL);
842 static void write_env_var(FILE *f, const char *v) {
848 fputs_unlocked(v, f);
849 fputc_unlocked('\n', f);
854 fwrite_unlocked(v, 1, p-v, f);
856 if (string_has_cc(p, NULL) || chars_intersect(p, WHITESPACE SHELL_NEED_QUOTES)) {
857 fputc_unlocked('\"', f);
860 if (strchr(SHELL_NEED_ESCAPE, *p))
861 fputc_unlocked('\\', f);
863 fputc_unlocked(*p, f);
866 fputc_unlocked('\"', f);
868 fputs_unlocked(p, f);
870 fputc_unlocked('\n', f);
873 int write_env_file(const char *fname, char **l) {
874 _cleanup_fclose_ FILE *f = NULL;
875 _cleanup_free_ char *p = NULL;
881 r = fopen_temporary(fname, &f, &p);
885 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
886 (void) fchmod_umask(fileno(f), 0644);
889 write_env_var(f, *i);
891 r = fflush_and_check(f);
893 if (rename(p, fname) >= 0)
903 int executable_is_script(const char *path, char **interpreter) {
904 _cleanup_free_ char *line = NULL;
911 r = read_one_line_file(path, &line);
912 if (r == -ENOBUFS) /* First line overly long? if so, then it's not a script */
917 if (!startswith(line, "#!"))
920 ans = strstrip(line + 2);
921 len = strcspn(ans, " \t");
926 ans = strndup(ans, len);
936 * Retrieve one field from a file like /proc/self/status. pattern
937 * should not include whitespace or the delimiter (':'). pattern matches only
938 * the beginning of a line. Whitespace before ':' is skipped. Whitespace and
939 * zeros after the ':' will be skipped. field must be freed afterwards.
940 * terminator specifies the terminating characters of the field value (not
941 * included in the value).
943 int get_proc_field(const char *filename, const char *pattern, const char *terminator, char **field) {
944 _cleanup_free_ char *status = NULL;
954 r = read_full_file(filename, &status, NULL);
964 t = strstr(t, pattern);
968 /* Check that pattern occurs in beginning of line. */
969 pattern_ok = (t == status || t[-1] == '\n');
971 t += strlen(pattern);
973 } while (!pattern_ok);
975 t += strspn(t, " \t");
984 t += strspn(t, " \t");
986 /* Also skip zeros, because when this is used for
987 * capabilities, we don't want the zeros. This way the
988 * same capability set always maps to the same string,
989 * irrespective of the total capability set size. For
990 * other numbers it shouldn't matter. */
992 /* Back off one char if there's nothing but whitespace
994 if (!*t || isspace(*t))
998 len = strcspn(t, terminator);
1000 f = strndup(t, len);
1008 DIR *xopendirat(int fd, const char *name, int flags) {
1012 assert(!(flags & O_CREAT));
1014 nfd = openat(fd, name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|flags, 0);
1027 #if 0 /// UNNEEDED by elogind
1028 static int search_and_fopen_internal(const char *path, const char *mode, const char *root, char **search, FILE **_f) {
1035 if (!path_strv_resolve_uniq(search, root))
1038 STRV_FOREACH(i, search) {
1039 _cleanup_free_ char *p = NULL;
1043 p = strjoin(root, *i, "/", path);
1045 p = strjoin(*i, "/", path);
1055 if (errno != ENOENT)
1062 int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **_f) {
1063 _cleanup_strv_free_ char **copy = NULL;
1069 if (path_is_absolute(path)) {
1072 f = fopen(path, mode);
1081 copy = strv_copy((char**) search);
1085 return search_and_fopen_internal(path, mode, root, copy, _f);
1088 int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **_f) {
1089 _cleanup_strv_free_ char **s = NULL;
1091 if (path_is_absolute(path)) {
1094 f = fopen(path, mode);
1103 s = strv_split_nulstr(search);
1107 return search_and_fopen_internal(path, mode, root, s, _f);
1111 int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
1120 r = tempfn_xxxxxx(path, NULL, &t);
1124 fd = mkostemp_safe(t);
1130 f = fdopen(fd, "we");
1144 int fflush_and_check(FILE *f) {
1151 return errno > 0 ? -errno : -EIO;
1156 int fflush_sync_and_check(FILE *f) {
1161 r = fflush_and_check(f);
1165 if (fsync(fileno(f)) < 0)
1168 r = fsync_directory_of_file(fileno(f));
1175 /* This is much like mkostemp() but is subject to umask(). */
1176 int mkostemp_safe(char *pattern) {
1177 _cleanup_umask_ mode_t u = 0;
1184 fd = mkostemp(pattern, O_CLOEXEC);
1191 int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
1203 * /foo/bar/.#<extra>waldoXXXXXX
1207 if (!filename_is_valid(fn))
1210 extra = strempty(extra);
1212 t = new(char, strlen(p) + 2 + strlen(extra) + 6 + 1);
1216 strcpy(stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn), "XXXXXX");
1218 *ret = path_kill_slashes(t);
1222 int tempfn_random(const char *p, const char *extra, char **ret) {
1236 * /foo/bar/.#<extra>waldobaa2a261115984a9
1240 if (!filename_is_valid(fn))
1243 extra = strempty(extra);
1245 t = new(char, strlen(p) + 2 + strlen(extra) + 16 + 1);
1249 x = stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn);
1252 for (i = 0; i < 16; i++) {
1253 *(x++) = hexchar(u & 0xF);
1259 *ret = path_kill_slashes(t);
1263 #if 0 /// UNNEEDED by elogind
1264 int tempfn_random_child(const char *p, const char *extra, char **ret) {
1275 * /foo/bar/waldo/.#<extra>3c2b6219aa75d7d0
1284 extra = strempty(extra);
1286 t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1);
1290 x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra);
1293 for (i = 0; i < 16; i++) {
1294 *(x++) = hexchar(u & 0xF);
1300 *ret = path_kill_slashes(t);
1304 int write_timestamp_file_atomic(const char *fn, usec_t n) {
1305 char ln[DECIMAL_STR_MAX(n)+2];
1307 /* Creates a "timestamp" file, that contains nothing but a
1308 * usec_t timestamp, formatted in ASCII. */
1310 if (n <= 0 || n >= USEC_INFINITY)
1313 xsprintf(ln, USEC_FMT "\n", n);
1315 return write_string_file(fn, ln, WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
1318 int read_timestamp_file(const char *fn, usec_t *ret) {
1319 _cleanup_free_ char *ln = NULL;
1323 r = read_one_line_file(fn, &ln);
1327 r = safe_atou64(ln, &t);
1331 if (t <= 0 || t >= (uint64_t) USEC_INFINITY)
1338 int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space) {
1343 /* Outputs the specified string with fputs(), but optionally prefixes it with a separator. The *space parameter
1344 * when specified shall initially point to a boolean variable initialized to false. It is set to true after the
1345 * first invocation. This call is supposed to be use in loops, where a separator shall be inserted between each
1346 * element, but not before the first one. */
1356 r = fputs(separator, f);
1368 int open_tmpfile_unlinkable(const char *directory, int flags) {
1373 r = tmp_dir(&directory);
1378 /* Returns an unlinked temporary file that cannot be linked into the file system anymore */
1380 /* Try O_TMPFILE first, if it is supported */
1381 fd = open(directory, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR);
1385 /* Fall back to unguessable name + unlinking */
1386 p = strjoina(directory, "/systemd-tmp-XXXXXX");
1388 fd = mkostemp_safe(p);
1397 #if 0 /// UNNEEDED by elogind
1398 int open_tmpfile_linkable(const char *target, int flags, char **ret_path) {
1399 _cleanup_free_ char *tmp = NULL;
1405 /* Don't allow O_EXCL, as that has a special meaning for O_TMPFILE */
1406 assert((flags & O_EXCL) == 0);
1408 /* Creates a temporary file, that shall be renamed to "target" later. If possible, this uses O_TMPFILE – in
1409 * which case "ret_path" will be returned as NULL. If not possible a the tempoary path name used is returned in
1410 * "ret_path". Use link_tmpfile() below to rename the result after writing the file in full. */
1413 _cleanup_free_ char *dn = NULL;
1415 dn = dirname_malloc(target);
1419 fd = open(dn, O_TMPFILE|flags, 0640);
1425 log_debug_errno(errno, "Failed to use O_TMPFILE on %s: %m", dn);
1428 r = tempfn_random(target, NULL, &tmp);
1432 fd = open(tmp, O_CREAT|O_EXCL|O_NOFOLLOW|O_NOCTTY|flags, 0640);
1436 *ret_path = TAKE_PTR(tmp);
1442 int open_serialization_fd(const char *ident) {
1445 fd = memfd_create(ident, MFD_CLOEXEC);
1449 path = getpid_cached() == 1 ? "/run/systemd" : "/tmp";
1450 fd = open_tmpfile_unlinkable(path, O_RDWR|O_CLOEXEC);
1454 log_debug("Serializing %s to %s.", ident, path);
1456 log_debug("Serializing %s to memfd.", ident);
1461 #if 0 /// UNNEEDED by elogind
1462 int link_tmpfile(int fd, const char *path, const char *target) {
1467 /* Moves a temporary file created with open_tmpfile() above into its final place. if "path" is NULL an fd
1468 * created with O_TMPFILE is assumed, and linkat() is used. Otherwise it is assumed O_TMPFILE is not supported
1469 * on the directory, and renameat2() is used instead.
1471 * Note that in both cases we will not replace existing files. This is because linkat() does not support this
1472 * operation currently (renameat2() does), and there is no nice way to emulate this. */
1475 if (rename_noreplace(AT_FDCWD, path, AT_FDCWD, target) < 0)
1478 char proc_fd_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(fd) + 1];
1480 xsprintf(proc_fd_path, "/proc/self/fd/%i", fd);
1482 if (linkat(AT_FDCWD, proc_fd_path, AT_FDCWD, target, AT_SYMLINK_FOLLOW) < 0)
1489 int read_nul_string(FILE *f, char **ret) {
1490 _cleanup_free_ char *x = NULL;
1491 size_t allocated = 0, n = 0;
1496 /* Reads a NUL-terminated string from the specified file. */
1501 if (!GREEDY_REALLOC(x, allocated, n+2))
1505 if (c == 0) /* Terminate at NUL byte */
1510 break; /* Terminate at EOF */
1529 int mkdtemp_malloc(const char *template, char **ret) {
1535 p = strdup(template);
1549 DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, funlockfile);
1551 int read_line(FILE *f, size_t limit, char **ret) {
1552 _cleanup_free_ char *buffer = NULL;
1553 size_t n = 0, allocated = 0, count = 0;
1557 /* Something like a bounded version of getline().
1559 * Considers EOF, \n and \0 end of line delimiters, and does not include these delimiters in the string
1562 * Returns the number of bytes read from the files (i.e. including delimiters — this hence usually differs from
1563 * the number of characters in the returned string). When EOF is hit, 0 is returned.
1565 * The input parameter limit is the maximum numbers of characters in the returned string, i.e. excluding
1566 * delimiters. If the limit is hit we fail and return -ENOBUFS.
1568 * If a line shall be skipped ret may be initialized as NULL. */
1571 if (!GREEDY_REALLOC(buffer, allocated, 1))
1576 _unused_ _cleanup_(funlockfilep) FILE *flocked = f;
1586 c = fgetc_unlocked(f);
1588 /* if we read an error, and have no data to return, then propagate the error */
1589 if (ferror_unlocked(f) && n == 0)
1590 return errno > 0 ? -errno : -EIO;
1597 if (IN_SET(c, '\n', 0)) /* Reached a delimiter */
1601 if (!GREEDY_REALLOC(buffer, allocated, n + 2))
1604 buffer[n] = (char) c;
1614 *ret = TAKE_PTR(buffer);