+
+DIR *xopendirat(int fd, const char *name, int flags) {
+ int nfd;
+ DIR *d;
+
+ assert(!(flags & O_CREAT));
+
+ nfd = openat(fd, name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|flags, 0);
+ if (nfd < 0)
+ return NULL;
+
+ d = fdopendir(nfd);
+ if (!d) {
+ safe_close(nfd);
+ return NULL;
+ }
+
+ return d;
+}
+
+#if 0 /// UNNEEDED by elogind
+static int search_and_fopen_internal(const char *path, const char *mode, const char *root, char **search, FILE **_f) {
+ char **i;
+
+ assert(path);
+ assert(mode);
+ assert(_f);
+
+ if (!path_strv_resolve_uniq(search, root))
+ return -ENOMEM;
+
+ STRV_FOREACH(i, search) {
+ _cleanup_free_ char *p = NULL;
+ FILE *f;
+
+ if (root)
+ p = strjoin(root, *i, "/", path);
+ else
+ p = strjoin(*i, "/", path);
+ if (!p)
+ return -ENOMEM;
+
+ f = fopen(p, mode);
+ if (f) {
+ *_f = f;
+ return 0;
+ }
+
+ if (errno != ENOENT)
+ return -errno;
+ }
+
+ return -ENOENT;
+}
+
+int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **_f) {
+ _cleanup_strv_free_ char **copy = NULL;
+
+ assert(path);
+ assert(mode);
+ assert(_f);
+
+ if (path_is_absolute(path)) {
+ FILE *f;
+
+ f = fopen(path, mode);
+ if (f) {
+ *_f = f;
+ return 0;
+ }
+
+ return -errno;
+ }
+
+ copy = strv_copy((char**) search);
+ if (!copy)
+ return -ENOMEM;
+
+ return search_and_fopen_internal(path, mode, root, copy, _f);
+}
+
+int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **_f) {
+ _cleanup_strv_free_ char **s = NULL;
+
+ if (path_is_absolute(path)) {
+ FILE *f;
+
+ f = fopen(path, mode);
+ if (f) {
+ *_f = f;
+ return 0;
+ }
+
+ return -errno;
+ }
+
+ s = strv_split_nulstr(search);
+ if (!s)
+ return -ENOMEM;
+
+ return search_and_fopen_internal(path, mode, root, s, _f);
+}
+#endif // 0
+
+int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
+ FILE *f;
+ char *t;
+ int r, fd;
+
+ assert(path);
+ assert(_f);
+ assert(_temp_path);
+
+ r = tempfn_xxxxxx(path, NULL, &t);
+ if (r < 0)
+ return r;
+
+ fd = mkostemp_safe(t);
+ if (fd < 0) {
+ free(t);
+ return -errno;
+ }
+
+ f = fdopen(fd, "we");
+ if (!f) {
+ unlink_noerrno(t);
+ free(t);
+ safe_close(fd);
+ return -errno;
+ }
+
+ *_f = f;
+ *_temp_path = t;
+
+ return 0;
+}
+
+int fflush_and_check(FILE *f) {
+ assert(f);
+
+ errno = 0;
+ fflush(f);
+
+ if (ferror(f))
+ return errno > 0 ? -errno : -EIO;
+
+ return 0;
+}
+
+/* This is much like mkostemp() but is subject to umask(). */
+int mkostemp_safe(char *pattern) {
+ _cleanup_umask_ mode_t u = 0;
+ int fd;
+
+ assert(pattern);
+
+ u = umask(077);
+
+ fd = mkostemp(pattern, O_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ return fd;
+}
+
+int tempfn_xxxxxx(const char *p, const char *extra, char **ret) {
+ const char *fn;
+ char *t;
+
+ assert(p);
+ assert(ret);
+
+ /*
+ * Turns this:
+ * /foo/bar/waldo
+ *
+ * Into this:
+ * /foo/bar/.#<extra>waldoXXXXXX
+ */
+
+ fn = basename(p);
+ if (!filename_is_valid(fn))
+ return -EINVAL;
+
+ if (extra == NULL)
+ extra = "";
+
+ t = new(char, strlen(p) + 2 + strlen(extra) + 6 + 1);
+ if (!t)
+ return -ENOMEM;
+
+ strcpy(stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn), "XXXXXX");
+
+ *ret = path_kill_slashes(t);
+ return 0;
+}
+
+int tempfn_random(const char *p, const char *extra, char **ret) {
+ const char *fn;
+ char *t, *x;
+ uint64_t u;
+ unsigned i;
+
+ assert(p);
+ assert(ret);
+
+ /*
+ * Turns this:
+ * /foo/bar/waldo
+ *
+ * Into this:
+ * /foo/bar/.#<extra>waldobaa2a261115984a9
+ */
+
+ fn = basename(p);
+ if (!filename_is_valid(fn))
+ return -EINVAL;
+
+ if (!extra)
+ extra = "";
+
+ t = new(char, strlen(p) + 2 + strlen(extra) + 16 + 1);
+ if (!t)
+ return -ENOMEM;
+
+ x = stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn);
+
+ u = random_u64();
+ for (i = 0; i < 16; i++) {
+ *(x++) = hexchar(u & 0xF);
+ u >>= 4;
+ }
+
+ *x = 0;
+
+ *ret = path_kill_slashes(t);
+ return 0;
+}
+
+#if 0 /// UNNEEDED by elogind
+int tempfn_random_child(const char *p, const char *extra, char **ret) {
+ char *t, *x;
+ uint64_t u;
+ unsigned i;
+ int r;
+
+ assert(ret);
+
+ /* Turns this:
+ * /foo/bar/waldo
+ * Into this:
+ * /foo/bar/waldo/.#<extra>3c2b6219aa75d7d0
+ */
+
+ if (!p) {
+ r = tmp_dir(&p);
+ if (r < 0)
+ return r;
+ }
+
+ if (!extra)
+ extra = "";
+
+ t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1);
+ if (!t)
+ return -ENOMEM;
+
+ x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra);
+
+ u = random_u64();
+ for (i = 0; i < 16; i++) {
+ *(x++) = hexchar(u & 0xF);
+ u >>= 4;
+ }
+
+ *x = 0;
+
+ *ret = path_kill_slashes(t);
+ return 0;
+}
+
+int write_timestamp_file_atomic(const char *fn, usec_t n) {
+ char ln[DECIMAL_STR_MAX(n)+2];
+
+ /* Creates a "timestamp" file, that contains nothing but a
+ * usec_t timestamp, formatted in ASCII. */
+
+ if (n <= 0 || n >= USEC_INFINITY)
+ return -ERANGE;
+
+ xsprintf(ln, USEC_FMT "\n", n);
+
+ return write_string_file(fn, ln, WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
+}
+
+int read_timestamp_file(const char *fn, usec_t *ret) {
+ _cleanup_free_ char *ln = NULL;
+ uint64_t t;
+ int r;
+
+ r = read_one_line_file(fn, &ln);
+ if (r < 0)
+ return r;
+
+ r = safe_atou64(ln, &t);
+ if (r < 0)
+ return r;
+
+ if (t <= 0 || t >= (uint64_t) USEC_INFINITY)
+ return -ERANGE;
+
+ *ret = (usec_t) t;
+ return 0;
+}
+
+int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space) {
+ int r;
+
+ assert(s);
+
+ /* Outputs the specified string with fputs(), but optionally prefixes it with a separator. The *space parameter
+ * when specified shall initially point to a boolean variable initialized to false. It is set to true after the
+ * first invocation. This call is supposed to be use in loops, where a separator shall be inserted between each
+ * element, but not before the first one. */
+
+ if (!f)
+ f = stdout;
+
+ if (space) {
+ if (!separator)
+ separator = " ";
+
+ if (*space) {
+ r = fputs(separator, f);
+ if (r < 0)
+ return r;
+ }
+
+ *space = true;
+ }
+
+ return fputs(s, f);
+}
+
+int open_tmpfile_unlinkable(const char *directory, int flags) {
+ char *p;
+ int fd, r;
+
+ if (!directory) {
+ r = tmp_dir(&directory);
+ if (r < 0)
+ return r;
+ }
+
+ /* Returns an unlinked temporary file that cannot be linked into the file system anymore */
+
+ /* Try O_TMPFILE first, if it is supported */
+ fd = open(directory, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR);
+ if (fd >= 0)
+ return fd;
+
+ /* Fall back to unguessable name + unlinking */
+ p = strjoina(directory, "/systemd-tmp-XXXXXX");
+
+ fd = mkostemp_safe(p);
+ if (fd < 0)
+ return fd;
+
+ (void) unlink(p);
+
+ return fd;
+}
+
+int open_tmpfile_linkable(const char *target, int flags, char **ret_path) {
+ _cleanup_free_ char *tmp = NULL;
+ int r, fd;
+
+ assert(target);
+ assert(ret_path);
+
+ /* Don't allow O_EXCL, as that has a special meaning for O_TMPFILE */
+ assert((flags & O_EXCL) == 0);
+
+ /* Creates a temporary file, that shall be renamed to "target" later. If possible, this uses O_TMPFILE – in
+ * which case "ret_path" will be returned as NULL. If not possible a the tempoary path name used is returned in
+ * "ret_path". Use link_tmpfile() below to rename the result after writing the file in full. */
+
+ {
+ _cleanup_free_ char *dn = NULL;
+
+ dn = dirname_malloc(target);
+ if (!dn)
+ return -ENOMEM;
+
+ fd = open(dn, O_TMPFILE|flags, 0640);
+ if (fd >= 0) {
+ *ret_path = NULL;
+ return fd;
+ }
+
+ log_debug_errno(errno, "Failed to use O_TMPFILE on %s: %m", dn);
+ }
+
+ r = tempfn_random(target, NULL, &tmp);
+ if (r < 0)
+ return r;
+
+ fd = open(tmp, O_CREAT|O_EXCL|O_NOFOLLOW|O_NOCTTY|flags, 0640);
+ if (fd < 0)
+ return -errno;
+
+ *ret_path = tmp;
+ tmp = NULL;
+
+ return fd;
+}
+
+int link_tmpfile(int fd, const char *path, const char *target) {
+
+ assert(fd >= 0);
+ assert(target);
+
+ /* Moves a temporary file created with open_tmpfile() above into its final place. if "path" is NULL an fd
+ * created with O_TMPFILE is assumed, and linkat() is used. Otherwise it is assumed O_TMPFILE is not supported
+ * on the directory, and renameat2() is used instead.
+ *
+ * Note that in both cases we will not replace existing files. This is because linkat() does not support this
+ * operation currently (renameat2() does), and there is no nice way to emulate this. */
+
+ if (path) {
+ if (rename_noreplace(AT_FDCWD, path, AT_FDCWD, target) < 0)
+ return -errno;
+ } else {
+ char proc_fd_path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(fd) + 1];
+
+ xsprintf(proc_fd_path, "/proc/self/fd/%i", fd);
+
+ if (linkat(AT_FDCWD, proc_fd_path, AT_FDCWD, target, AT_SYMLINK_FOLLOW) < 0)
+ return -errno;
+ }
+
+ return 0;
+}
+#endif // 0
+
+int read_nul_string(FILE *f, char **ret) {
+ _cleanup_free_ char *x = NULL;
+ size_t allocated = 0, n = 0;
+
+ assert(f);
+ assert(ret);
+
+ /* Reads a NUL-terminated string from the specified file. */
+
+ for (;;) {
+ int c;
+
+ if (!GREEDY_REALLOC(x, allocated, n+2))
+ return -ENOMEM;
+
+ c = fgetc(f);
+ if (c == 0) /* Terminate at NUL byte */
+ break;
+ if (c == EOF) {
+ if (ferror(f))
+ return -errno;
+ break; /* Terminate at EOF */
+ }
+
+ x[n++] = (char) c;
+ }
+
+ if (x)
+ x[n] = 0;
+ else {
+ x = new0(char, 1);
+ if (!x)
+ return -ENOMEM;
+ }
+
+ *ret = x;
+ x = NULL;
+
+ return 0;
+}
+
+int mkdtemp_malloc(const char *template, char **ret) {
+ char *p;
+
+ assert(template);
+ assert(ret);
+
+ p = strdup(template);
+ if (!p)
+ return -ENOMEM;
+
+ if (!mkdtemp(p)) {
+ free(p);
+ return -errno;
+ }
+
+ *ret = p;
+ return 0;
+}