chiark / gitweb /
util: the chattr flags field is actually unsigned, judging by kernel sources
[elogind.git] / src / shared / util.c
index 364f61885b00a1b3f9a076a993b982f74468ba7e..9fd2d89556819500d9c602cce6f99a60cf45c02c 100644 (file)
@@ -39,7 +39,6 @@
 #include <linux/tiocl.h>
 #include <termios.h>
 #include <stdarg.h>
-#include <sys/inotify.h>
 #include <sys/poll.h>
 #include <ctype.h>
 #include <sys/prctl.h>
 #include <langinfo.h>
 #include <locale.h>
 #include <sys/personality.h>
+#include <sys/xattr.h>
 #include <libgen.h>
+#include <sys/statvfs.h>
+#include <linux/fs.h>
 #undef basename
 
 #ifdef HAVE_SYS_AUXV_H
@@ -85,6 +87,7 @@
 #include "gunicode.h"
 #include "virt.h"
 #include "def.h"
+#include "sparse-endian.h"
 
 int saved_argc = 0;
 char **saved_argv = NULL;
@@ -521,7 +524,7 @@ int safe_atod(const char *s, double *ret_d) {
 
 static size_t strcspn_escaped(const char *s, const char *reject) {
         bool escaped = false;
-        size_t n;
+        int n;
 
         for (n=0; s[n]; n++) {
                 if (escaped)
@@ -531,6 +534,7 @@ static size_t strcspn_escaped(const char *s, const char *reject) {
                 else if (strchr(reject, s[n]))
                         break;
         }
+
         /* if s ends in \, return index of previous char */
         return n - escaped;
 }
@@ -566,6 +570,11 @@ const char* split(const char **state, size_t *l, const char *separator, bool quo
                 *state = current++ + *l + 2;
         } else if (quoted) {
                 *l = strcspn_escaped(current, separator);
+                if (current[*l] && !strchr(separator, current[*l])) {
+                        /* unfinished escape */
+                        *state = current;
+                        return NULL;
+                }
                 *state = current + *l;
         } else {
                 *l = strcspn(current, separator);
@@ -1145,7 +1154,7 @@ char *delete_chars(char *s, const char *bad) {
 }
 
 char *file_in_same_dir(const char *path, const char *filename) {
-        char *e, *r;
+        char *e, *ret;
         size_t k;
 
         assert(path);
@@ -1158,17 +1167,17 @@ char *file_in_same_dir(const char *path, const char *filename) {
         if (path_is_absolute(filename))
                 return strdup(filename);
 
-        if (!(e = strrchr(path, '/')))
+        e = strrchr(path, '/');
+        if (!e)
                 return strdup(filename);
 
         k = strlen(filename);
-        if (!(r = new(char, e-path+1+k+1)))
+        ret = new(char, (e + 1 - path) + k + 1);
+        if (!ret)
                 return NULL;
 
-        memcpy(r, path, e-path+1);
-        memcpy(r+(e-path)+1, filename, k+1);
-
-        return r;
+        memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1);
+        return ret;
 }
 
 int rmdir_parents(const char *path, const char *stop) {
@@ -1343,12 +1352,19 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
                 memcpy(r, prefix, pl);
 
         for (f = s, t = r + pl; f < s + length; f++) {
+                size_t remaining = s + length - f;
+                assert(remaining > 0);
 
-                if (*f != '\\') {
+                if (*f != '\\') {        /* a literal literal */
                         *(t++) = *f;
                         continue;
                 }
 
+                if (--remaining == 0) {  /* copy trailing backslash verbatim */
+                        *(t++) = *f;
+                        break;
+                }
+
                 f++;
 
                 switch (*f) {
@@ -1391,10 +1407,12 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
 
                 case 'x': {
                         /* hexadecimal encoding */
-                        int a, b;
+                        int a = -1, b = -1;
 
-                        a = unhexchar(f[1]);
-                        b = unhexchar(f[2]);
+                        if (remaining >= 2) {
+                                a = unhexchar(f[1]);
+                                b = unhexchar(f[2]);
+                        }
 
                         if (a < 0 || b < 0 || (a == 0 && b == 0)) {
                                 /* Invalid escape code, let's take it literal then */
@@ -1417,11 +1435,13 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
                 case '6':
                 case '7': {
                         /* octal encoding */
-                        int a, b, c;
+                        int a = -1, b = -1, c = -1;
 
-                        a = unoctchar(f[0]);
-                        b = unoctchar(f[1]);
-                        c = unoctchar(f[2]);
+                        if (remaining >= 3) {
+                                a = unoctchar(f[0]);
+                                b = unoctchar(f[1]);
+                                c = unoctchar(f[2]);
+                        }
 
                         if (a < 0 || b < 0 || c < 0 || (a == 0 && b == 0 && c == 0)) {
                                 /* Invalid escape code, let's take it literal then */
@@ -1435,11 +1455,6 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
                         break;
                 }
 
-                case 0:
-                        /* premature end of string. */
-                        *(t++) = '\\';
-                        goto finish;
-
                 default:
                         /* Invalid escape code, let's take it literal then */
                         *(t++) = '\\';
@@ -1448,7 +1463,6 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
                 }
         }
 
-finish:
         *t = 0;
         return r;
 }
@@ -1504,7 +1518,7 @@ char *ascii_strlower(char *t) {
         return t;
 }
 
-_pure_ static bool ignore_file_allow_backup(const char *filename) {
+_pure_ static bool hidden_file_allow_backup(const char *filename) {
         assert(filename);
 
         return
@@ -1521,13 +1535,13 @@ _pure_ static bool ignore_file_allow_backup(const char *filename) {
                 endswith(filename, ".swp");
 }
 
-bool ignore_file(const char *filename) {
+bool hidden_file(const char *filename) {
         assert(filename);
 
         if (endswith(filename, "~"))
                 return true;
 
-        return ignore_file_allow_backup(filename);
+        return hidden_file_allow_backup(filename);
 }
 
 int fd_nonblock(int fd, bool nonblock) {
@@ -1621,7 +1635,7 @@ int close_all_fds(const int except[], unsigned n_except) {
         while ((de = readdir(d))) {
                 int fd = -1;
 
-                if (ignore_file(de->d_name))
+                if (hidden_file(de->d_name))
                         continue;
 
                 if (safe_atoi(de->d_name, &fd) < 0)
@@ -2100,7 +2114,7 @@ int acquire_terminal(
                 assert(notify >= 0);
 
                 for (;;) {
-                        uint8_t buffer[INOTIFY_EVENT_MAX] _alignas_(struct inotify_event);
+                        union inotify_event_buffer buffer;
                         struct inotify_event *e;
                         ssize_t l;
 
@@ -2123,7 +2137,7 @@ int acquire_terminal(
                                 }
                         }
 
-                        l = read(notify, buffer, sizeof(buffer));
+                        l = read(notify, &buffer, sizeof(buffer));
                         if (l < 0) {
                                 if (errno == EINTR || errno == EAGAIN)
                                         continue;
@@ -2525,7 +2539,7 @@ int dir_is_empty(const char *path) {
                 if (!de)
                         return 1;
 
-                if (!ignore_file(de->d_name))
+                if (!hidden_file(de->d_name))
                         return 0;
         }
 }
@@ -2779,23 +2793,36 @@ char *getusername_malloc(void) {
         return lookup_uid(getuid());
 }
 
-int getttyname_malloc(int fd, char **r) {
-        char path[PATH_MAX], *c;
-        int k;
+int getttyname_malloc(int fd, char **ret) {
+        size_t l = 100;
+        int r;
 
-        assert(r);
+        assert(fd >= 0);
+        assert(ret);
 
-        k = ttyname_r(fd, path, sizeof(path));
-        if (k > 0)
-                return -k;
+        for (;;) {
+                char path[l];
 
-        char_array_0(path);
+                r = ttyname_r(fd, path, sizeof(path));
+                if (r == 0) {
+                        const char *p;
+                        char *c;
 
-        c = strdup(startswith(path, "/dev/") ? path + 5 : path);
-        if (!c)
-                return -ENOMEM;
+                        p = startswith(path, "/dev/");
+                        c = strdup(p ?: path);
+                        if (!c)
+                                return -ENOMEM;
+
+                        *ret = c;
+                        return 0;
+                }
+
+                if (r != ERANGE)
+                        return -r;
+
+                l *= 2;
+        }
 
-        *r = c;
         return 0;
 }
 
@@ -3063,7 +3090,7 @@ static int rm_rf_internal(const char *path, bool only_dirs, bool delete_root, bo
         fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
         if (fd < 0) {
 
-                if (errno != ENOTDIR)
+                if (errno != ENOTDIR && errno != ELOOP)
                         return -errno;
 
                 if (!dangerous) {
@@ -3436,7 +3463,7 @@ unsigned columns(void) {
                 c = 80;
 
         cached_columns = c;
-        return c;
+        return cached_columns;
 }
 
 int fd_lines(int fd) {
@@ -3453,7 +3480,7 @@ int fd_lines(int fd) {
 
 unsigned lines(void) {
         const char *e;
-        unsigned l;
+        int l;
 
         if (_likely_(cached_lines > 0))
                 return cached_lines;
@@ -3461,7 +3488,7 @@ unsigned lines(void) {
         l = 0;
         e = getenv("LINES");
         if (e)
-                (void) safe_atou(e, &l);
+                (void) safe_atoi(e, &l);
 
         if (l <= 0)
                 l = fd_lines(STDOUT_FILENO);
@@ -3984,13 +4011,13 @@ bool tty_is_vc_resolve(const char *tty) {
 const char *default_term_for_tty(const char *tty) {
         assert(tty);
 
-        return tty_is_vc_resolve(tty) ? "TERM=linux" : "TERM=vt102";
+        return tty_is_vc_resolve(tty) ? "TERM=linux" : "TERM=vt220";
 }
 
 bool dirent_is_file(const struct dirent *de) {
         assert(de);
 
-        if (ignore_file(de->d_name))
+        if (hidden_file(de->d_name))
                 return false;
 
         if (de->d_type != DT_REG &&
@@ -4009,70 +4036,72 @@ bool dirent_is_file_with_suffix(const struct dirent *de, const char *suffix) {
             de->d_type != DT_UNKNOWN)
                 return false;
 
-        if (ignore_file_allow_backup(de->d_name))
+        if (hidden_file_allow_backup(de->d_name))
                 return false;
 
         return endswith(de->d_name, suffix);
 }
 
-void execute_directory(const char *directory, DIR *d, usec_t timeout, char *argv[]) {
-        pid_t executor_pid;
-        int r;
+static int do_execute(char **directories, usec_t timeout, char *argv[]) {
+        _cleanup_hashmap_free_free_ Hashmap *pids = NULL;
+        _cleanup_set_free_free_ Set *seen = NULL;
+        char **directory;
 
-        assert(directory);
+        /* We fork this all off from a child process so that we can
+         * somewhat cleanly make use of SIGALRM to set a time limit */
 
-        /* Executes all binaries in a directory in parallel and waits
-         * for them to finish. Optionally a timeout is applied. */
+        reset_all_signal_handlers();
+        reset_signal_mask();
 
-        executor_pid = fork();
-        if (executor_pid < 0) {
-                log_error_errno(errno, "Failed to fork: %m");
-                return;
+        assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
 
-        } else if (executor_pid == 0) {
-                _cleanup_hashmap_free_free_ Hashmap *pids = NULL;
-                _cleanup_closedir_ DIR *_d = NULL;
-                struct dirent *de;
-
-                /* We fork this all off from a child process so that
-                 * we can somewhat cleanly make use of SIGALRM to set
-                 * a time limit */
+        pids = hashmap_new(NULL);
+        if (!pids)
+                return log_oom();
 
-                reset_all_signal_handlers();
-                reset_signal_mask();
+        seen = set_new(&string_hash_ops);
+        if (!seen)
+                return log_oom();
 
-                assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
+        STRV_FOREACH(directory, directories) {
+                _cleanup_closedir_ DIR *d;
+                struct dirent *de;
 
+                d = opendir(*directory);
                 if (!d) {
-                        d = _d = opendir(directory);
-                        if (!d) {
-                                if (errno == ENOENT)
-                                        _exit(EXIT_SUCCESS);
+                        if (errno == ENOENT)
+                                continue;
 
-                                log_error_errno(errno, "Failed to enumerate directory %s: %m", directory);
-                                _exit(EXIT_FAILURE);
-                        }
-                }
-
-                pids = hashmap_new(NULL);
-                if (!pids) {
-                        log_oom();
-                        _exit(EXIT_FAILURE);
+                        return log_error_errno(errno, "Failed to open directory %s: %m", *directory);
                 }
 
                 FOREACH_DIRENT(de, d, break) {
                         _cleanup_free_ char *path = NULL;
                         pid_t pid;
+                        int r;
 
                         if (!dirent_is_file(de))
                                 continue;
 
-                        path = strjoin(directory, "/", de->d_name, NULL);
-                        if (!path) {
-                                log_oom();
-                                _exit(EXIT_FAILURE);
+                        if (set_contains(seen, de->d_name)) {
+                                log_debug("%1$s/%2$s skipped (%2$s was already seen).", *directory, de->d_name);
+                                continue;
                         }
 
+                        r = set_put_strdup(seen, de->d_name);
+                        if (r < 0)
+                                return log_oom();
+
+                        path = strjoin(*directory, "/", de->d_name, NULL);
+                        if (!path)
+                                return log_oom();
+
+                        if (null_or_empty_path(path)) {
+                                log_debug("%s is empty (a mask).", path);
+                                continue;
+                        } else
+                                log_debug("%s will be executed.", path);
+
                         pid = fork();
                         if (pid < 0) {
                                 log_error_errno(errno, "Failed to fork: %m");
@@ -4090,45 +4119,68 @@ void execute_directory(const char *directory, DIR *d, usec_t timeout, char *argv
                                         argv[0] = path;
 
                                 execv(path, argv);
-                                log_error_errno(errno, "Failed to execute %s: %m", path);
-                                _exit(EXIT_FAILURE);
+                                return log_error_errno(errno, "Failed to execute %s: %m", path);
                         }
 
                         log_debug("Spawned %s as " PID_FMT ".", path, pid);
 
                         r = hashmap_put(pids, UINT_TO_PTR(pid), path);
-                        if (r < 0) {
-                                log_oom();
-                                _exit(EXIT_FAILURE);
-                        }
-
+                        if (r < 0)
+                                return log_oom();
                         path = NULL;
                 }
+        }
 
-                /* Abort execution of this process after the
-                 * timout. We simply rely on SIGALRM as default action
-                 * terminating the process, and turn on alarm(). */
+        /* Abort execution of this process after the timout. We simply
+         * rely on SIGALRM as default action terminating the process,
+         * and turn on alarm(). */
 
-                if (timeout != USEC_INFINITY)
-                        alarm((timeout + USEC_PER_SEC - 1) / USEC_PER_SEC);
+        if (timeout != USEC_INFINITY)
+                alarm((timeout + USEC_PER_SEC - 1) / USEC_PER_SEC);
 
-                while (!hashmap_isempty(pids)) {
-                        _cleanup_free_ char *path = NULL;
-                        pid_t pid;
+        while (!hashmap_isempty(pids)) {
+                _cleanup_free_ char *path = NULL;
+                pid_t pid;
 
-                        pid = PTR_TO_UINT(hashmap_first_key(pids));
-                        assert(pid > 0);
+                pid = PTR_TO_UINT(hashmap_first_key(pids));
+                assert(pid > 0);
 
-                        path = hashmap_remove(pids, UINT_TO_PTR(pid));
-                        assert(path);
+                path = hashmap_remove(pids, UINT_TO_PTR(pid));
+                assert(path);
 
-                        wait_for_terminate_and_warn(path, pid, true);
-                }
+                wait_for_terminate_and_warn(path, pid, true);
+        }
 
-                _exit(EXIT_SUCCESS);
+        return 0;
+}
+
+void execute_directories(const char* const* directories, usec_t timeout, char *argv[]) {
+        pid_t executor_pid;
+        int r;
+        char *name;
+        char **dirs = (char**) directories;
+
+        assert(!strv_isempty(dirs));
+
+        name = basename(dirs[0]);
+        assert(!isempty(name));
+
+        /* Executes all binaries in the directories in parallel and waits
+         * for them to finish. Optionally a timeout is applied. If a file
+         * with the same name exists in more than one directory, the
+         * earliest one wins. */
+
+        executor_pid = fork();
+        if (executor_pid < 0) {
+                log_error_errno(errno, "Failed to fork: %m");
+                return;
+
+        } else if (executor_pid == 0) {
+                r = do_execute(dirs, timeout, argv);
+                _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
         }
 
-        wait_for_terminate_and_warn(directory, executor_pid, true);
+        wait_for_terminate_and_warn(name, executor_pid, true);
 }
 
 int kill_and_sigcont(pid_t pid, int sig) {
@@ -4251,6 +4303,23 @@ bool machine_name_is_valid(const char *s) {
         return true;
 }
 
+bool image_name_is_valid(const char *s) {
+        if (!filename_is_valid(s))
+                return false;
+
+        if (string_has_cc(s, NULL))
+                return false;
+
+        if (!utf8_is_valid(s))
+                return false;
+
+        /* Temporary files for atomically creating new files */
+        if (startswith(s, ".#"))
+                return false;
+
+        return true;
+}
+
 int pipe_eof(int fd) {
         struct pollfd pollfd = {
                 .fd = fd,
@@ -5147,6 +5216,9 @@ char *format_bytes(char *buf, size_t l, off_t t) {
                 { "K", 1024ULL },
         };
 
+        if (t == (off_t) -1)
+                return NULL;
+
         for (i = 0; i < ELEMENTSOF(table); i++) {
 
                 if (t >= table[i].factor) {
@@ -5903,7 +5975,7 @@ int on_ac_power(void) {
                 if (!de)
                         break;
 
-                if (ignore_file(de->d_name))
+                if (hidden_file(de->d_name))
                         continue;
 
                 device = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY|O_CLOEXEC|O_NOCTTY);
@@ -6677,23 +6749,6 @@ uint64_t physical_memory(void) {
         return (uint64_t) mem * (uint64_t) page_size();
 }
 
-char* mount_test_option(const char *haystack, const char *needle) {
-
-        struct mntent me = {
-                .mnt_opts = (char*) haystack
-        };
-
-        assert(needle);
-
-        /* Like glibc's hasmntopt(), but works on a string, not a
-         * struct mntent */
-
-        if (!haystack)
-                return NULL;
-
-        return hasmntopt(&me, needle);
-}
-
 void hexdump(FILE *f, const void *p, size_t s) {
         const uint8_t *b = p;
         unsigned n = 0;
@@ -6818,6 +6873,15 @@ int umount_recursive(const char *prefix, int flags) {
         return r ? r : n;
 }
 
+static int get_mount_flags(const char *path, unsigned long *flags) {
+        struct statvfs buf;
+
+        if (statvfs(path, &buf) < 0)
+                return -errno;
+        *flags = buf.f_flag;
+        return 0;
+}
+
 int bind_remount_recursive(const char *prefix, bool ro) {
         _cleanup_set_free_free_ Set *done = NULL;
         _cleanup_free_ char *cleaned = NULL;
@@ -6852,6 +6916,7 @@ int bind_remount_recursive(const char *prefix, bool ro) {
                 _cleanup_set_free_free_ Set *todo = NULL;
                 bool top_autofs = false;
                 char *x;
+                unsigned long orig_flags;
 
                 todo = set_new(&string_hash_ops);
                 if (!todo)
@@ -6929,7 +6994,11 @@ int bind_remount_recursive(const char *prefix, bool ro) {
                         if (mount(cleaned, cleaned, NULL, MS_BIND|MS_REC, NULL) < 0)
                                 return -errno;
 
-                        if (mount(NULL, prefix, NULL, MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0)
+                        orig_flags = 0;
+                        (void) get_mount_flags(cleaned, &orig_flags);
+                        orig_flags &= ~MS_RDONLY;
+
+                        if (mount(NULL, prefix, NULL, orig_flags|MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0)
                                 return -errno;
 
                         x = strdup(cleaned);
@@ -6949,7 +7018,14 @@ int bind_remount_recursive(const char *prefix, bool ro) {
                         if (r < 0)
                                 return r;
 
-                        if (mount(NULL, x, NULL, MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) {
+                        /* Try to reuse the original flag set, but
+                         * don't care for errors, in case of
+                         * obstructed mounts */
+                        orig_flags = 0;
+                        (void) get_mount_flags(x, &orig_flags);
+                        orig_flags &= ~MS_RDONLY;
+
+                        if (mount(NULL, x, NULL, orig_flags|MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) {
 
                                 /* Deal with mount points that are
                                  * obstructed by a later mount */
@@ -6986,18 +7062,18 @@ int tempfn_xxxxxx(const char *p, char **ret) {
          *         /foo/bar/waldo
          *
          * Into this:
-         *         /foo/bar/.waldoXXXXXX
+         *         /foo/bar/.#waldoXXXXXX
          */
 
         fn = basename(p);
         if (!filename_is_valid(fn))
                 return -EINVAL;
 
-        t = new(char, strlen(p) + 1 + 6 + 1);
+        t = new(char, strlen(p) + 2 + 6 + 1);
         if (!t)
                 return -ENOMEM;
 
-        strcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), "."), fn), "XXXXXX");
+        strcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), "XXXXXX");
 
         *ret = path_kill_slashes(t);
         return 0;
@@ -7017,18 +7093,18 @@ int tempfn_random(const char *p, char **ret) {
          *         /foo/bar/waldo
          *
          * Into this:
-         *         /foo/bar/.waldobaa2a261115984a9
+         *         /foo/bar/.#waldobaa2a261115984a9
          */
 
         fn = basename(p);
         if (!filename_is_valid(fn))
                 return -EINVAL;
 
-        t = new(char, strlen(p) + 1 + 16 + 1);
+        t = new(char, strlen(p) + 2 + 16 + 1);
         if (!t)
                 return -ENOMEM;
 
-        x = stpcpy(stpcpy(mempcpy(t, p, fn - p), "."), fn);
+        x = stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn);
 
         u = random_u64();
         for (i = 0; i < 16; i++) {
@@ -7053,14 +7129,14 @@ int tempfn_random_child(const char *p, char **ret) {
         /* Turns this:
          *         /foo/bar/waldo
          * Into this:
-         *         /foo/bar/waldo/.3c2b6219aa75d7d0
+         *         /foo/bar/waldo/.#3c2b6219aa75d7d0
          */
 
-        t = new(char, strlen(p) + 2 + 16 + 1);
+        t = new(char, strlen(p) + 3 + 16 + 1);
         if (!t)
                 return -ENOMEM;
 
-        x = stpcpy(stpcpy(t, p), "/.");
+        x = stpcpy(stpcpy(t, p), "/.#");
 
         u = random_u64();
         for (i = 0; i < 16; i++) {
@@ -7410,3 +7486,314 @@ int sethostname_idempotent(const char *s) {
 
         return 1;
 }
+
+int ptsname_malloc(int fd, char **ret) {
+        size_t l = 100;
+
+        assert(fd >= 0);
+        assert(ret);
+
+        for (;;) {
+                char *c;
+
+                c = new(char, l);
+                if (!c)
+                        return -ENOMEM;
+
+                if (ptsname_r(fd, c, l) == 0) {
+                        *ret = c;
+                        return 0;
+                }
+                if (errno != ERANGE) {
+                        free(c);
+                        return -errno;
+                }
+
+                free(c);
+                l *= 2;
+        }
+}
+
+int openpt_in_namespace(pid_t pid, int flags) {
+        _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1;
+        _cleanup_close_pair_ int pair[2] = { -1, -1 };
+        union {
+                struct cmsghdr cmsghdr;
+                uint8_t buf[CMSG_SPACE(sizeof(int))];
+        } control = {};
+        struct msghdr mh = {
+                .msg_control = &control,
+                .msg_controllen = sizeof(control),
+        };
+        struct cmsghdr *cmsg;
+        siginfo_t si;
+        pid_t child;
+        int r;
+
+        assert(pid > 0);
+
+        r = namespace_open(pid, &pidnsfd, &mntnsfd, NULL, &rootfd);
+        if (r < 0)
+                return r;
+
+        if (socketpair(AF_UNIX, SOCK_DGRAM, 0, pair) < 0)
+                return -errno;
+
+        child = fork();
+        if (child < 0)
+                return -errno;
+
+        if (child == 0) {
+                int master;
+
+                pair[0] = safe_close(pair[0]);
+
+                r = namespace_enter(pidnsfd, mntnsfd, -1, rootfd);
+                if (r < 0)
+                        _exit(EXIT_FAILURE);
+
+                master = posix_openpt(flags);
+                if (master < 0)
+                        _exit(EXIT_FAILURE);
+
+                cmsg = CMSG_FIRSTHDR(&mh);
+                cmsg->cmsg_level = SOL_SOCKET;
+                cmsg->cmsg_type = SCM_RIGHTS;
+                cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+                memcpy(CMSG_DATA(cmsg), &master, sizeof(int));
+
+                mh.msg_controllen = cmsg->cmsg_len;
+
+                if (sendmsg(pair[1], &mh, MSG_NOSIGNAL) < 0)
+                        _exit(EXIT_FAILURE);
+
+                _exit(EXIT_SUCCESS);
+        }
+
+        pair[1] = safe_close(pair[1]);
+
+        r = wait_for_terminate(child, &si);
+        if (r < 0)
+                return r;
+        if (si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS)
+                return -EIO;
+
+        if (recvmsg(pair[0], &mh, MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) < 0)
+                return -errno;
+
+        for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg))
+                if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
+                        int *fds;
+                        unsigned n_fds;
+
+                        fds = (int*) CMSG_DATA(cmsg);
+                        n_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
+
+                        if (n_fds != 1) {
+                                close_many(fds, n_fds);
+                                return -EIO;
+                        }
+
+                        return fds[0];
+                }
+
+        return -EIO;
+}
+
+ssize_t fgetxattrat_fake(int dirfd, const char *filename, const char *attribute, void *value, size_t size, int flags) {
+        _cleanup_close_ int fd = -1;
+        ssize_t l;
+
+        /* The kernel doesn't have a fgetxattrat() command, hence let's emulate one */
+
+        fd = openat(dirfd, filename, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOATIME|(flags & AT_SYMLINK_NOFOLLOW ? O_NOFOLLOW : 0));
+        if (fd < 0)
+                return -errno;
+
+        l = fgetxattr(fd, attribute, value, size);
+        if (l < 0)
+                return -errno;
+
+        return l;
+}
+
+static int parse_crtime(le64_t le, usec_t *usec) {
+        uint64_t u;
+
+        assert(usec);
+
+        u = le64toh(le);
+        if (u == 0 || u == (uint64_t) -1)
+                return -EIO;
+
+        *usec = (usec_t) u;
+        return 0;
+}
+
+int fd_getcrtime(int fd, usec_t *usec) {
+        le64_t le;
+        ssize_t n;
+
+        assert(fd >= 0);
+        assert(usec);
+
+        /* Until Linux gets a real concept of birthtime/creation time,
+         * let's fake one with xattrs */
+
+        n = fgetxattr(fd, "user.crtime_usec", &le, sizeof(le));
+        if (n < 0)
+                return -errno;
+        if (n != sizeof(le))
+                return -EIO;
+
+        return parse_crtime(le, usec);
+}
+
+int fd_getcrtime_at(int dirfd, const char *name, usec_t *usec, int flags) {
+        le64_t le;
+        ssize_t n;
+
+        n = fgetxattrat_fake(dirfd, name, "user.crtime_usec", &le, sizeof(le), flags);
+        if (n < 0)
+                return -errno;
+        if (n != sizeof(le))
+                return -EIO;
+
+        return parse_crtime(le, usec);
+}
+
+int path_getcrtime(const char *p, usec_t *usec) {
+        le64_t le;
+        ssize_t n;
+
+        assert(p);
+        assert(usec);
+
+        n = getxattr(p, "user.crtime_usec", &le, sizeof(le));
+        if (n < 0)
+                return -errno;
+        if (n != sizeof(le))
+                return -EIO;
+
+        return parse_crtime(le, usec);
+}
+
+int fd_setcrtime(int fd, usec_t usec) {
+        le64_t le;
+
+        assert(fd >= 0);
+
+        if (usec <= 0)
+                usec = now(CLOCK_REALTIME);
+
+        le = htole64((uint64_t) usec);
+        if (fsetxattr(fd, "user.crtime_usec", &le, sizeof(le), 0) < 0)
+                return -errno;
+
+        return 0;
+}
+
+int same_fd(int a, int b) {
+        struct stat sta, stb;
+        pid_t pid;
+        int r, fa, fb;
+
+        assert(a >= 0);
+        assert(b >= 0);
+
+        /* Compares two file descriptors. Note that semantics are
+         * quite different depending on whether we have kcmp() or we
+         * don't. If we have kcmp() this will only return true for
+         * dup()ed file descriptors, but not otherwise. If we don't
+         * have kcmp() this will also return true for two fds of the same
+         * file, created by separate open() calls. Since we use this
+         * call mostly for filtering out duplicates in the fd store
+         * this difference hopefully doesn't matter too much. */
+
+        if (a == b)
+                return true;
+
+        /* Try to use kcmp() if we have it. */
+        pid = getpid();
+        r = kcmp(pid, pid, KCMP_FILE, a, b);
+        if (r == 0)
+                return true;
+        if (r > 0)
+                return false;
+        if (errno != ENOSYS)
+                return -errno;
+
+        /* We don't have kcmp(), use fstat() instead. */
+        if (fstat(a, &sta) < 0)
+                return -errno;
+
+        if (fstat(b, &stb) < 0)
+                return -errno;
+
+        if ((sta.st_mode & S_IFMT) != (stb.st_mode & S_IFMT))
+                return false;
+
+        /* We consider all device fds different, since two device fds
+         * might refer to quite different device contexts even though
+         * they share the same inode and backing dev_t. */
+
+        if (S_ISCHR(sta.st_mode) || S_ISBLK(sta.st_mode))
+                return false;
+
+        if (sta.st_dev != stb.st_dev || sta.st_ino != stb.st_ino)
+                return false;
+
+        /* The fds refer to the same inode on disk, let's also check
+         * if they have the same fd flags. This is useful to
+         * distuingish the read and write side of a pipe created with
+         * pipe(). */
+        fa = fcntl(a, F_GETFL);
+        if (fa < 0)
+                return -errno;
+
+        fb = fcntl(b, F_GETFL);
+        if (fb < 0)
+                return -errno;
+
+        return fa == fb;
+}
+
+int chattr_fd(int fd, bool b, unsigned mask) {
+        unsigned old_attr, new_attr;
+
+        assert(fd >= 0);
+
+        if (mask == 0)
+                return 0;
+
+        if (ioctl(fd, FS_IOC_GETFLAGS, &old_attr) < 0)
+                return -errno;
+
+        if (b)
+                new_attr = old_attr | mask;
+        else
+                new_attr = old_attr & ~mask;
+
+        if (new_attr == old_attr)
+                return 0;
+
+        if (ioctl(fd, FS_IOC_SETFLAGS, &new_attr) < 0)
+                return -errno;
+
+        return 0;
+}
+
+int chattr_path(const char *p, bool b, unsigned mask) {
+        _cleanup_close_ int fd = -1;
+
+        assert(p);
+
+        if (mask == 0)
+                return 0;
+
+        fd = open(p, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
+        if (fd < 0)
+                return -errno;
+
+        return chattr_fd(fd, b, mask);
+}