chiark / gitweb /
util: replace RUN_WITH_LOCALE with extended locale functions
[elogind.git] / src / shared / util.c
index bc97c67f768900abdd06462d2eb0dc91cb37cd9e..8f6d5e660c657356a429d115c17823f3412b2945 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 <sys/file.h>
+#include <linux/fs.h>
 #undef basename
 
 #ifdef HAVE_SYS_AUXV_H
@@ -85,6 +88,7 @@
 #include "gunicode.h"
 #include "virt.h"
 #include "def.h"
+#include "sparse-endian.h"
 
 int saved_argc = 0;
 char **saved_argv = NULL;
@@ -174,6 +178,69 @@ char* first_word(const char *s, const char *word) {
         return (char*) p;
 }
 
+static size_t cescape_char(char c, char *buf) {
+        char * buf_old = buf;
+
+        switch (c) {
+
+                case '\a':
+                        *(buf++) = '\\';
+                        *(buf++) = 'a';
+                        break;
+                case '\b':
+                        *(buf++) = '\\';
+                        *(buf++) = 'b';
+                        break;
+                case '\f':
+                        *(buf++) = '\\';
+                        *(buf++) = 'f';
+                        break;
+                case '\n':
+                        *(buf++) = '\\';
+                        *(buf++) = 'n';
+                        break;
+                case '\r':
+                        *(buf++) = '\\';
+                        *(buf++) = 'r';
+                        break;
+                case '\t':
+                        *(buf++) = '\\';
+                        *(buf++) = 't';
+                        break;
+                case '\v':
+                        *(buf++) = '\\';
+                        *(buf++) = 'v';
+                        break;
+                case '\\':
+                        *(buf++) = '\\';
+                        *(buf++) = '\\';
+                        break;
+                case '"':
+                        *(buf++) = '\\';
+                        *(buf++) = '"';
+                        break;
+                case '\'':
+                        *(buf++) = '\\';
+                        *(buf++) = '\'';
+                        break;
+
+                default:
+                        /* For special chars we prefer octal over
+                         * hexadecimal encoding, simply because glib's
+                         * g_strescape() does the same */
+                        if ((c < ' ') || (c >= 127)) {
+                                *(buf++) = '\\';
+                                *(buf++) = octchar((unsigned char) c >> 6);
+                                *(buf++) = octchar((unsigned char) c >> 3);
+                                *(buf++) = octchar((unsigned char) c);
+                        } else
+                                *(buf++) = c;
+                        break;
+        }
+
+        return buf - buf_old;
+}
+
 int close_nointr(int fd) {
         assert(fd >= 0);
 
@@ -291,7 +358,7 @@ int parse_uid(const char *s, uid_t* ret_uid) {
         if ((unsigned long) uid != ul)
                 return -ERANGE;
 
-        /* Some libc APIs use (uid_t) -1 as special placeholder */
+        /* Some libc APIs use UID_INVALID as special placeholder */
         if (uid == (uid_t) 0xFFFFFFFF)
                 return -ENXIO;
 
@@ -363,6 +430,46 @@ int safe_atou8(const char *s, uint8_t *ret) {
         return 0;
 }
 
+int safe_atou16(const char *s, uint16_t *ret) {
+        char *x = NULL;
+        unsigned long l;
+
+        assert(s);
+        assert(ret);
+
+        errno = 0;
+        l = strtoul(s, &x, 0);
+
+        if (!x || x == s || *x || errno)
+                return errno > 0 ? -errno : -EINVAL;
+
+        if ((unsigned long) (uint16_t) l != l)
+                return -ERANGE;
+
+        *ret = (uint16_t) l;
+        return 0;
+}
+
+int safe_atoi16(const char *s, int16_t *ret) {
+        char *x = NULL;
+        long l;
+
+        assert(s);
+        assert(ret);
+
+        errno = 0;
+        l = strtol(s, &x, 0);
+
+        if (!x || x == s || *x || errno)
+                return errno > 0 ? -errno : -EINVAL;
+
+        if ((long) (int16_t) l != l)
+                return -ERANGE;
+
+        *ret = (int16_t) l;
+        return 0;
+}
+
 int safe_atollu(const char *s, long long unsigned *ret_llu) {
         char *x = NULL;
         unsigned long long l;
@@ -400,25 +507,31 @@ int safe_atolli(const char *s, long long int *ret_lli) {
 int safe_atod(const char *s, double *ret_d) {
         char *x = NULL;
         double d = 0;
+        locale_t loc;
 
         assert(s);
         assert(ret_d);
 
-        RUN_WITH_LOCALE(LC_NUMERIC_MASK, "C") {
-                errno = 0;
-                d = strtod(s, &x);
-        }
+        loc = newlocale(LC_NUMERIC_MASK, "C", (locale_t) 0);
+        if (loc == (locale_t) 0)
+                return -errno;
 
-        if (!x || x == s || *x || errno)
+        errno = 0;
+        d = strtod_l(s, &x, loc);
+
+        if (!x || x == s || *x || errno) {
+                freelocale(loc);
                 return errno ? -errno : -EINVAL;
+        }
 
+        freelocale(loc);
         *ret_d = (double) d;
         return 0;
 }
 
 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)
@@ -428,6 +541,7 @@ 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;
 }
@@ -455,7 +569,7 @@ const char* split(const char **state, size_t *l, const char *separator, bool quo
                 *l = strcspn_escaped(current + 1, quotechars);
                 if (current[*l + 1] == '\0' ||
                     (current[*l + 2] && !strchr(separator, current[*l + 2]))) {
-                        /* right quote missing or garbage at the end*/
+                        /* right quote missing or garbage at the end */
                         *state = current;
                         return NULL;
                 }
@@ -463,6 +577,11 @@ 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);
@@ -515,56 +634,6 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
         return 0;
 }
 
-int get_starttime_of_pid(pid_t pid, unsigned long long *st) {
-        int r;
-        _cleanup_free_ char *line = NULL;
-        const char *p;
-
-        assert(pid >= 0);
-        assert(st);
-
-        p = procfs_file_alloca(pid, "stat");
-        r = read_one_line_file(p, &line);
-        if (r < 0)
-                return r;
-
-        /* Let's skip the pid and comm fields. The latter is enclosed
-         * in () but does not escape any () in its value, so let's
-         * skip over it manually */
-
-        p = strrchr(line, ')');
-        if (!p)
-                return -EIO;
-
-        p++;
-
-        if (sscanf(p, " "
-                   "%*c "  /* state */
-                   "%*d "  /* ppid */
-                   "%*d "  /* pgrp */
-                   "%*d "  /* session */
-                   "%*d "  /* tty_nr */
-                   "%*d "  /* tpgid */
-                   "%*u "  /* flags */
-                   "%*u "  /* minflt */
-                   "%*u "  /* cminflt */
-                   "%*u "  /* majflt */
-                   "%*u "  /* cmajflt */
-                   "%*u "  /* utime */
-                   "%*u "  /* stime */
-                   "%*d "  /* cutime */
-                   "%*d "  /* cstime */
-                   "%*d "  /* priority */
-                   "%*d "  /* nice */
-                   "%*d "  /* num_threads */
-                   "%*d "  /* itrealvalue */
-                   "%llu "  /* starttime */,
-                   st) != 1)
-                return -EIO;
-
-        return 0;
-}
-
 int fchmod_umask(int fd, mode_t m) {
         mode_t u;
         int r;
@@ -695,7 +764,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
         }
 
         /* Kernel threads have no argv[] */
-        if (r == NULL || r[0] == 0) {
+        if (isempty(r)) {
                 _cleanup_free_ char *t = NULL;
                 int h;
 
@@ -757,19 +826,30 @@ int get_process_capeff(pid_t pid, char **capeff) {
         return get_status_field(p, "\nCapEff:", capeff);
 }
 
+static int get_process_link_contents(const char *proc_file, char **name) {
+        int r;
+
+        assert(proc_file);
+        assert(name);
+
+        r = readlink_malloc(proc_file, name);
+        if (r < 0)
+                return r == -ENOENT ? -ESRCH : r;
+
+        return 0;
+}
+
 int get_process_exe(pid_t pid, char **name) {
         const char *p;
         char *d;
         int r;
 
         assert(pid >= 0);
-        assert(name);
 
         p = procfs_file_alloca(pid, "exe");
-
-        r = readlink_malloc(p, name);
+        r = get_process_link_contents(p, name);
         if (r < 0)
-                return r == -ENOENT ? -ESRCH : r;
+                return r;
 
         d = endswith(*name, " (deleted)");
         if (d)
@@ -821,6 +901,59 @@ int get_process_gid(pid_t pid, gid_t *gid) {
         return get_process_id(pid, "Gid:", gid);
 }
 
+int get_process_cwd(pid_t pid, char **cwd) {
+        const char *p;
+
+        assert(pid >= 0);
+
+        p = procfs_file_alloca(pid, "cwd");
+
+        return get_process_link_contents(p, cwd);
+}
+
+int get_process_root(pid_t pid, char **root) {
+        const char *p;
+
+        assert(pid >= 0);
+
+        p = procfs_file_alloca(pid, "root");
+
+        return get_process_link_contents(p, root);
+}
+
+int get_process_environ(pid_t pid, char **env) {
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_free_ char *outcome = NULL;
+        int c;
+        const char *p;
+        size_t allocated = 0, sz = 0;
+
+        assert(pid >= 0);
+        assert(env);
+
+        p = procfs_file_alloca(pid, "environ");
+
+        f = fopen(p, "re");
+        if (!f)
+                return -errno;
+
+        while ((c = fgetc(f)) != EOF) {
+                if (!GREEDY_REALLOC(outcome, allocated, sz + 5))
+                        return -ENOMEM;
+
+                if (c == '\0')
+                        outcome[sz++] = '\n';
+                else
+                        sz += cescape_char(c, outcome + sz);
+        }
+
+        outcome[sz] = '\0';
+        *env = outcome;
+        outcome = NULL;
+
+        return 0;
+}
+
 char *strnappend(const char *s, const char *suffix, size_t b) {
         size_t a;
         char *r;
@@ -893,6 +1026,28 @@ int readlink_malloc(const char *p, char **ret) {
         return readlinkat_malloc(AT_FDCWD, p, ret);
 }
 
+int readlink_value(const char *p, char **ret) {
+        _cleanup_free_ char *link = NULL;
+        char *value;
+        int r;
+
+        r = readlink_malloc(p, &link);
+        if (r < 0)
+                return r;
+
+        value = basename(link);
+        if (!value)
+                return -ENOENT;
+
+        value = strdup(value);
+        if (!value)
+                return -ENOMEM;
+
+        *ret = value;
+
+        return 0;
+}
+
 int readlink_and_make_absolute(const char *p, char **r) {
         _cleanup_free_ char *target = NULL;
         char *k;
@@ -1006,7 +1161,7 @@ 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);
@@ -1019,17 +1174,17 @@ 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) {
@@ -1178,63 +1333,7 @@ char *cescape(const char *s) {
                 return NULL;
 
         for (f = s, t = r; *f; f++)
-
-                switch (*f) {
-
-                case '\a':
-                        *(t++) = '\\';
-                        *(t++) = 'a';
-                        break;
-                case '\b':
-                        *(t++) = '\\';
-                        *(t++) = 'b';
-                        break;
-                case '\f':
-                        *(t++) = '\\';
-                        *(t++) = 'f';
-                        break;
-                case '\n':
-                        *(t++) = '\\';
-                        *(t++) = 'n';
-                        break;
-                case '\r':
-                        *(t++) = '\\';
-                        *(t++) = 'r';
-                        break;
-                case '\t':
-                        *(t++) = '\\';
-                        *(t++) = 't';
-                        break;
-                case '\v':
-                        *(t++) = '\\';
-                        *(t++) = 'v';
-                        break;
-                case '\\':
-                        *(t++) = '\\';
-                        *(t++) = '\\';
-                        break;
-                case '"':
-                        *(t++) = '\\';
-                        *(t++) = '"';
-                        break;
-                case '\'':
-                        *(t++) = '\\';
-                        *(t++) = '\'';
-                        break;
-
-                default:
-                        /* For special chars we prefer octal over
-                         * hexadecimal encoding, simply because glib's
-                         * g_strescape() does the same */
-                        if ((*f < ' ') || (*f >= 127)) {
-                                *(t++) = '\\';
-                                *(t++) = octchar((unsigned char) *f >> 6);
-                                *(t++) = octchar((unsigned char) *f >> 3);
-                                *(t++) = octchar((unsigned char) *f);
-                        } else
-                                *(t++) = *f;
-                        break;
-                }
+                t += cescape_char(*f, t);
 
         *t = 0;
 
@@ -1260,12 +1359,19 @@ 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) {
@@ -1308,10 +1414,12 @@ 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 */
@@ -1334,11 +1442,13 @@ 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 */
@@ -1352,11 +1462,6 @@ 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++) = '\\';
@@ -1365,7 +1470,6 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre
                 }
         }
 
-finish:
         *t = 0;
         return r;
 }
@@ -1421,7 +1525,7 @@ 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
@@ -1438,13 +1542,13 @@ _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) {
@@ -1538,7 +1642,7 @@ 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)
@@ -2017,9 +2121,9 @@ int acquire_terminal(
                 assert(notify >= 0);
 
                 for (;;) {
-                        uint8_t inotify_buffer[sizeof(struct inotify_event) + FILENAME_MAX];
-                        ssize_t l;
+                        union inotify_event_buffer buffer;
                         struct inotify_event *e;
+                        ssize_t l;
 
                         if (timeout != USEC_INFINITY) {
                                 usec_t n;
@@ -2040,9 +2144,8 @@ int acquire_terminal(
                                 }
                         }
 
-                        l = read(notify, inotify_buffer, sizeof(inotify_buffer));
+                        l = read(notify, &buffer, sizeof(buffer));
                         if (l < 0) {
-
                                 if (errno == EINTR || errno == EAGAIN)
                                         continue;
 
@@ -2050,21 +2153,11 @@ int acquire_terminal(
                                 goto fail;
                         }
 
-                        e = (struct inotify_event*) inotify_buffer;
-
-                        while (l > 0) {
-                                size_t step;
-
+                        FOREACH_INOTIFY_EVENT(e, buffer, l) {
                                 if (e->wd != wd || !(e->mask & IN_CLOSE)) {
                                         r = -EIO;
                                         goto fail;
                                 }
-
-                                step = sizeof(struct inotify_event) + e->len;
-                                assert(step <= (size_t) l);
-
-                                e = (struct inotify_event*) ((uint8_t*) e + step);
-                                l -= step;
                         }
 
                         break;
@@ -2081,7 +2174,7 @@ int acquire_terminal(
 
         r = reset_terminal_fd(fd, true);
         if (r < 0)
-                log_warning("Failed to reset terminal: %s", strerror(-r));
+                log_warning_errno(r, "Failed to reset terminal: %m");
 
         return fd;
 
@@ -2196,21 +2289,25 @@ ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) {
                 ssize_t k;
 
                 k = read(fd, p, nbytes);
-                if (k < 0 && errno == EINTR)
-                        continue;
+                if (k < 0) {
+                        if (errno == EINTR)
+                                continue;
 
-                if (k < 0 && errno == EAGAIN && do_poll) {
+                        if (errno == EAGAIN && do_poll) {
 
-                        /* We knowingly ignore any return value here,
-                         * and expect that any error/EOF is reported
-                         * via read() */
+                                /* We knowingly ignore any return value here,
+                                 * and expect that any error/EOF is reported
+                                 * via read() */
 
-                        fd_wait_for_event(fd, POLLIN, USEC_INFINITY);
-                        continue;
+                                fd_wait_for_event(fd, POLLIN, USEC_INFINITY);
+                                continue;
+                        }
+
+                        return n > 0 ? n : -errno;
                 }
 
-                if (k <= 0)
-                        return n > 0 ? n : (k < 0 ? -errno : 0);
+                if (k == 0)
+                        return n;
 
                 p += k;
                 nbytes -= k;
@@ -2220,39 +2317,42 @@ ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) {
         return n;
 }
 
-ssize_t loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) {
+int loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) {
         const uint8_t *p = buf;
-        ssize_t n = 0;
 
         assert(fd >= 0);
         assert(buf);
 
+        errno = 0;
+
         while (nbytes > 0) {
                 ssize_t k;
 
                 k = write(fd, p, nbytes);
-                if (k < 0 && errno == EINTR)
-                        continue;
+                if (k < 0) {
+                        if (errno == EINTR)
+                                continue;
 
-                if (k < 0 && errno == EAGAIN && do_poll) {
+                        if (errno == EAGAIN && do_poll) {
+                                /* We knowingly ignore any return value here,
+                                 * and expect that any error/EOF is reported
+                                 * via write() */
 
-                        /* We knowingly ignore any return value here,
-                         * and expect that any error/EOF is reported
-                         * via write() */
+                                fd_wait_for_event(fd, POLLOUT, USEC_INFINITY);
+                                continue;
+                        }
 
-                        fd_wait_for_event(fd, POLLOUT, USEC_INFINITY);
-                        continue;
+                        return -errno;
                 }
 
-                if (k <= 0)
-                        return n > 0 ? n : (k < 0 ? -errno : 0);
+                if (k == 0) /* Can't really happen */
+                        return -EIO;
 
                 p += k;
                 nbytes -= k;
-                n += k;
         }
 
-        return n;
+        return 0;
 }
 
 int parse_size(const char *t, off_t base, off_t *size) {
@@ -2389,9 +2489,9 @@ int make_stdio(int fd) {
 
         assert(fd >= 0);
 
-        r = dup3(fd, STDIN_FILENO, 0);
-        s = dup3(fd, STDOUT_FILENO, 0);
-        t = dup3(fd, STDERR_FILENO, 0);
+        r = dup2(fd, STDIN_FILENO);
+        s = dup2(fd, STDOUT_FILENO);
+        t = dup2(fd, STDERR_FILENO);
 
         if (fd >= 3)
                 safe_close(fd);
@@ -2399,7 +2499,11 @@ int make_stdio(int fd) {
         if (r < 0 || s < 0 || t < 0)
                 return -errno;
 
-        /* We rely here that the new fd has O_CLOEXEC not set */
+        /* Explicitly unset O_CLOEXEC, since if fd was < 3, then
+         * dup2() was a NOP and the bit hence possibly set. */
+        fd_cloexec(STDIN_FILENO, false);
+        fd_cloexec(STDOUT_FILENO, false);
+        fd_cloexec(STDERR_FILENO, false);
 
         return 0;
 }
@@ -2442,7 +2546,7 @@ 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;
         }
 }
@@ -2466,14 +2570,53 @@ char* dirname_malloc(const char *path) {
 }
 
 int dev_urandom(void *p, size_t n) {
-        _cleanup_close_ int fd;
+        static int have_syscall = -1;
+        int r, fd;
         ssize_t k;
 
+        /* Gathers some randomness from the kernel. This call will
+         * never block, and will always return some data from the
+         * kernel, regardless if the random pool is fully initialized
+         * or not. It thus makes no guarantee for the quality of the
+         * returned entropy, but is good enough for or usual usecases
+         * of seeding the hash functions for hashtable */
+
+        /* Use the getrandom() syscall unless we know we don't have
+         * it, or when the requested size is too large for it. */
+        if (have_syscall != 0 || (size_t) (int) n != n) {
+                r = getrandom(p, n, GRND_NONBLOCK);
+                if (r == (int) n) {
+                        have_syscall = true;
+                        return 0;
+                }
+
+                if (r < 0) {
+                        if (errno == ENOSYS)
+                                /* we lack the syscall, continue with
+                                 * reading from /dev/urandom */
+                                have_syscall = false;
+                        else if (errno == EAGAIN)
+                                /* not enough entropy for now. Let's
+                                 * remember to use the syscall the
+                                 * next time, again, but also read
+                                 * from /dev/urandom for now, which
+                                 * doesn't care about the current
+                                 * amount of entropy.  */
+                                have_syscall = true;
+                        else
+                                return -errno;
+                } else
+                        /* too short read? */
+                        return -EIO;
+        }
+
         fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY);
         if (fd < 0)
                 return errno == ENOENT ? -ENOSYS : -errno;
 
         k = loop_read(fd, p, n, true);
+        safe_close(fd);
+
         if (k < 0)
                 return (int) k;
         if ((size_t) k != n)
@@ -2482,8 +2625,36 @@ int dev_urandom(void *p, size_t n) {
         return 0;
 }
 
-void random_bytes(void *p, size_t n) {
+void initialize_srand(void) {
         static bool srand_called = false;
+        unsigned x;
+#ifdef HAVE_SYS_AUXV_H
+        void *auxv;
+#endif
+
+        if (srand_called)
+                return;
+
+        x = 0;
+
+#ifdef HAVE_SYS_AUXV_H
+        /* The kernel provides us with a bit of entropy in auxv, so
+         * let's try to make use of that to seed the pseudo-random
+         * generator. It's better than nothing... */
+
+        auxv = (void*) getauxval(AT_RANDOM);
+        if (auxv)
+                x ^= *(unsigned*) auxv;
+#endif
+
+        x ^= (unsigned) now(CLOCK_REALTIME);
+        x ^= (unsigned) gettid();
+
+        srand(x);
+        srand_called = true;
+}
+
+void random_bytes(void *p, size_t n) {
         uint8_t *q;
         int r;
 
@@ -2494,28 +2665,7 @@ void random_bytes(void *p, size_t n) {
         /* If some idiot made /dev/urandom unavailable to us, he'll
          * get a PRNG instead. */
 
-        if (!srand_called) {
-                unsigned x = 0;
-
-#ifdef HAVE_SYS_AUXV_H
-                /* The kernel provides us with a bit of entropy in
-                 * auxv, so let's try to make use of that to seed the
-                 * pseudo-random generator. It's better than
-                 * nothing... */
-
-                void *auxv;
-
-                auxv = (void*) getauxval(AT_RANDOM);
-                if (auxv)
-                        x ^= *(unsigned*) auxv;
-#endif
-
-                x ^= (unsigned) now(CLOCK_REALTIME);
-                x ^= (unsigned) gettid();
-
-                srand(x);
-                srand_called = true;
-        }
+        initialize_srand();
 
         for (q = p; q < (uint8_t*) p + n; q ++)
                 *q = rand();
@@ -2650,23 +2800,36 @@ 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;
 }
 
@@ -2737,7 +2900,7 @@ int get_ctty(pid_t pid, dev_t *_devnr, char **r) {
         if (k < 0)
                 return k;
 
-        snprintf(fn, sizeof(fn), "/dev/char/%u:%u", major(devnr), minor(devnr));
+        sprintf(fn, "/dev/char/%u:%u", major(devnr), minor(devnr));
 
         k = readlink_malloc(fn, &s);
         if (k < 0) {
@@ -2873,6 +3036,15 @@ _pure_ static int is_temporary_fs(struct statfs *s) {
                F_TYPE_EQUAL(s->f_type, RAMFS_MAGIC);
 }
 
+int is_fd_on_temporary_fs(int fd) {
+        struct statfs s;
+
+        if (fstatfs(fd, &s) < 0)
+                return -errno;
+
+        return is_temporary_fs(&s);
+}
+
 int rm_rf_children(int fd, bool only_dirs, bool honour_sticky, struct stat *root_dev) {
         struct statfs s;
 
@@ -2895,6 +3067,19 @@ int rm_rf_children(int fd, bool only_dirs, bool honour_sticky, struct stat *root
         return rm_rf_children_dangerous(fd, only_dirs, honour_sticky, root_dev);
 }
 
+static int file_is_priv_sticky(const char *p) {
+        struct stat st;
+
+        assert(p);
+
+        if (lstat(p, &st) < 0)
+                return -errno;
+
+        return
+                (st.st_uid == 0 || st.st_uid == getuid()) &&
+                (st.st_mode & S_ISVTX);
+}
+
 static int rm_rf_internal(const char *path, bool only_dirs, bool delete_root, bool honour_sticky, bool dangerous) {
         int fd, r;
         struct statfs s;
@@ -2912,7 +3097,7 @@ 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) {
@@ -2975,11 +3160,11 @@ int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid) {
          * first change the access mode and only then hand out
          * ownership to avoid a window where access is too open. */
 
-        if (mode != (mode_t) -1)
+        if (mode != MODE_INVALID)
                 if (chmod(path, mode) < 0)
                         return -errno;
 
-        if (uid != (uid_t) -1 || gid != (gid_t) -1)
+        if (uid != UID_INVALID || gid != GID_INVALID)
                 if (chown(path, uid, gid) < 0)
                         return -errno;
 
@@ -2993,11 +3178,11 @@ int fchmod_and_fchown(int fd, mode_t mode, uid_t uid, gid_t gid) {
          * first change the access mode and only then hand out
          * ownership to avoid a window where access is too open. */
 
-        if (mode != (mode_t) -1)
+        if (mode != MODE_INVALID)
                 if (fchmod(fd, mode) < 0)
                         return -errno;
 
-        if (uid != (uid_t) -1 || gid != (gid_t) -1)
+        if (uid != UID_INVALID || gid != GID_INVALID)
                 if (fchown(fd, uid, gid) < 0)
                         return -errno;
 
@@ -3133,7 +3318,8 @@ char *replace_env(const char *format, char **env) {
 
                 case CURLY:
                         if (*e == '{') {
-                                if (!(k = strnappend(r, word, e-word-1)))
+                                k = strnappend(r, word, e-word-1);
+                                if (!k)
                                         goto fail;
 
                                 free(r);
@@ -3143,7 +3329,8 @@ char *replace_env(const char *format, char **env) {
                                 state = VARIABLE;
 
                         } else if (*e == '$') {
-                                if (!(k = strnappend(r, word, e-word)))
+                                k = strnappend(r, word, e-word);
+                                if (!k)
                                         goto fail;
 
                                 free(r);
@@ -3175,7 +3362,8 @@ char *replace_env(const char *format, char **env) {
                 }
         }
 
-        if (!(k = strnappend(r, word, e-word)))
+        k = strnappend(r, word, e-word);
+        if (!k)
                 goto fail;
 
         free(r);
@@ -3208,7 +3396,7 @@ char **replace_env_argv(char **argv, char **env) {
                         if (e) {
                                 int r;
 
-                                r = strv_split_quoted(&m, e);
+                                r = strv_split_quoted(&m, e, true);
                                 if (r < 0) {
                                         ret[k] = NULL;
                                         strv_free(ret);
@@ -3282,7 +3470,7 @@ unsigned columns(void) {
                 c = 80;
 
         cached_columns = c;
-        return c;
+        return cached_columns;
 }
 
 int fd_lines(int fd) {
@@ -3299,7 +3487,7 @@ int fd_lines(int fd) {
 
 unsigned lines(void) {
         const char *e;
-        unsigned l;
+        int l;
 
         if (_likely_(cached_lines > 0))
                 return cached_lines;
@@ -3307,7 +3495,7 @@ 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);
@@ -3485,7 +3673,7 @@ int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gi
                         return -errno;
         }
 
-        if (uid != (uid_t) -1 || gid != (gid_t) -1) {
+        if (uid != UID_INVALID || gid != GID_INVALID) {
                 r = fchown(fd, uid, gid);
                 if (r < 0)
                         return -errno;
@@ -3506,7 +3694,7 @@ int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gi
 }
 
 int touch(const char *path) {
-        return touch_file(path, false, USEC_INFINITY, (uid_t) -1, (gid_t) -1, 0);
+        return touch_file(path, false, USEC_INFINITY, UID_INVALID, GID_INVALID, 0);
 }
 
 char *unquote(const char *s, const char* quotes) {
@@ -3516,7 +3704,7 @@ char *unquote(const char *s, const char* quotes) {
         /* This is rather stupid, simply removes the heading and
          * trailing quotes if there is one. Doesn't care about
          * escaping or anything. We should make this smarter one
-         * day...*/
+         * day... */
 
         l = strlen(s);
         if (l < 2)
@@ -3529,41 +3717,33 @@ char *unquote(const char *s, const char* quotes) {
 }
 
 char *normalize_env_assignment(const char *s) {
-        _cleanup_free_ char *name = NULL, *value = NULL, *p = NULL;
-        char *eq, *r;
+        _cleanup_free_ char *value = NULL;
+        const char *eq;
+        char *p, *name;
 
         eq = strchr(s, '=');
         if (!eq) {
-                char *t;
+                char *r, *t;
 
                 r = strdup(s);
                 if (!r)
                         return NULL;
 
                 t = strstrip(r);
-                if (t == r)
-                        return r;
+                if (t != r)
+                        memmove(r, t, strlen(t) + 1);
 
-                memmove(r, t, strlen(t) + 1);
                 return r;
         }
 
-        name = strndup(s, eq - s);
-        if (!name)
-                return NULL;
-
-        p = strdup(eq + 1);
-        if (!p)
-                return NULL;
+        name = strndupa(s, eq - s);
+        p = strdupa(eq + 1);
 
         value = unquote(strstrip(p), QUOTES);
         if (!value)
                 return NULL;
 
-        if (asprintf(&r, "%s=%s", strstrip(name), value) < 0)
-                r = NULL;
-
-        return r;
+        return strjoin(strstrip(name), "=", value, NULL);
 }
 
 int wait_for_terminate(pid_t pid, siginfo_t *status) {
@@ -3599,8 +3779,11 @@ int wait_for_terminate(pid_t pid, siginfo_t *status) {
  *
  * That is, success is indicated by a return value of zero, and an
  * error is indicated by a non-zero value.
+ *
+ * A warning is emitted if the process terminates abnormally,
+ * and also if it returns non-zero unless check_exit_code is true.
  */
-int wait_for_terminate_and_warn(const char *name, pid_t pid) {
+int wait_for_terminate_and_warn(const char *name, pid_t pid, bool check_exit_code) {
         int r;
         siginfo_t status;
 
@@ -3608,20 +3791,17 @@ int wait_for_terminate_and_warn(const char *name, pid_t pid) {
         assert(pid > 1);
 
         r = wait_for_terminate(pid, &status);
-        if (r < 0) {
-                log_warning("Failed to wait for %s: %s", name, strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_warning_errno(r, "Failed to wait for %s: %m", name);
 
         if (status.si_code == CLD_EXITED) {
-                if (status.si_status != 0) {
-                        log_warning("%s failed with error code %i.", name, status.si_status);
-                        return status.si_status;
-                }
-
-                log_debug("%s succeeded.", name);
-                return 0;
+                if (status.si_status != 0)
+                        log_full(check_exit_code ? LOG_WARNING : LOG_DEBUG,
+                                 "%s failed with error code %i.", name, status.si_status);
+                else
+                        log_debug("%s succeeded.", name);
 
+                return status.si_status;
         } else if (status.si_code == CLD_KILLED ||
                    status.si_code == CLD_DUMPED) {
 
@@ -3838,13 +4018,13 @@ 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 &&
@@ -3863,73 +4043,75 @@ 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;
-
-        assert(directory);
+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;
 
-        /* Executes all binaries in a directory in parallel and waits
-         * for them to finish. Optionally a timeout is applied. */
+        /* We fork this all off from a child process so that we can
+         * somewhat cleanly make use of SIGALRM to set a time limit */
 
-        executor_pid = fork();
-        if (executor_pid < 0) {
-                log_error("Failed to fork: %m");
-                return;
+        reset_all_signal_handlers();
+        reset_signal_mask();
 
-        } else if (executor_pid == 0) {
-                _cleanup_hashmap_free_free_ Hashmap *pids = NULL;
-                _cleanup_closedir_ DIR *_d = NULL;
-                struct dirent *de;
+        assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
 
-                /* 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);
-
-                                log_error("Failed to enumerate directory %s: %m", directory);
-                                _exit(EXIT_FAILURE);
-                        }
-                }
+                        if (errno == ENOENT)
+                                continue;
 
-                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("Failed to fork: %m");
+                                log_error_errno(errno, "Failed to fork: %m");
                                 continue;
                         } else if (pid == 0) {
                                 char *_argv[2];
@@ -3944,45 +4126,68 @@ void execute_directory(const char *directory, DIR *d, usec_t timeout, char *argv
                                         argv[0] = path;
 
                                 execv(path, argv);
-                                log_error("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);
-                }
+                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);
+        wait_for_terminate_and_warn(name, executor_pid, true);
 }
 
 int kill_and_sigcont(pid_t pid, int sig) {
@@ -4146,15 +4351,15 @@ int fd_wait_for_event(int fd, int event, usec_t t) {
 int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
         FILE *f;
         char *t;
-        int fd;
+        int r, fd;
 
         assert(path);
         assert(_f);
         assert(_temp_path);
 
-        t = tempfn_xxxxxx(path);
-        if (!t)
-                return -ENOMEM;
+        r = tempfn_xxxxxx(path, &t);
+        if (r < 0)
+                return r;
 
         fd = mkostemp_safe(t, O_WRONLY|O_CLOEXEC);
         if (fd < 0) {
@@ -4265,13 +4470,14 @@ int vt_disallocate(const char *name) {
 
 int symlink_atomic(const char *from, const char *to) {
         _cleanup_free_ char *t = NULL;
+        int r;
 
         assert(from);
         assert(to);
 
-        t = tempfn_random(to);
-        if (!t)
-                return -ENOMEM;
+        r = tempfn_random(to, &t);
+        if (r < 0)
+                return r;
 
         if (symlink(from, t) < 0)
                 return -errno;
@@ -4286,12 +4492,13 @@ int symlink_atomic(const char *from, const char *to) {
 
 int mknod_atomic(const char *path, mode_t mode, dev_t dev) {
         _cleanup_free_ char *t = NULL;
+        int r;
 
         assert(path);
 
-        t = tempfn_random(path);
-        if (!t)
-                return -ENOMEM;
+        r = tempfn_random(path, &t);
+        if (r < 0)
+                return r;
 
         if (mknod(t, mode, dev) < 0)
                 return -errno;
@@ -4306,12 +4513,13 @@ int mknod_atomic(const char *path, mode_t mode, dev_t dev) {
 
 int mkfifo_atomic(const char *path, mode_t mode) {
         _cleanup_free_ char *t = NULL;
+        int r;
 
         assert(path);
 
-        t = tempfn_random(path);
-        if (!t)
-                return -ENOMEM;
+        r = tempfn_random(path, &t);
+        if (r < 0)
+                return r;
 
         if (mkfifo(t, mode) < 0)
                 return -errno;
@@ -4780,19 +4988,6 @@ int block_get_whole_disk(dev_t d, dev_t *ret) {
         return -ENOENT;
 }
 
-int file_is_priv_sticky(const char *p) {
-        struct stat st;
-
-        assert(p);
-
-        if (lstat(p, &st) < 0)
-                return -errno;
-
-        return
-                (st.st_uid == 0 || st.st_uid == getuid()) &&
-                (st.st_mode & S_ISVTX);
-}
-
 static const char *const ioprio_class_table[] = {
         [IOPRIO_CLASS_NONE] = "none",
         [IOPRIO_CLASS_RT] = "realtime",
@@ -5011,6 +5206,9 @@ 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) {
@@ -5149,7 +5347,7 @@ int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *pa
                  * keep an unused copy of stdin around. */
                 fd = open("/dev/tty", O_WRONLY);
                 if (fd < 0) {
-                        log_error("Failed to open /dev/tty: %m");
+                        log_error_errno(errno, "Failed to open /dev/tty: %m");
                         _exit(EXIT_FAILURE);
                 }
 
@@ -5332,16 +5530,12 @@ int make_console_stdio(void) {
         /* Make /dev/console the controlling terminal and stdin/stdout/stderr */
 
         fd = acquire_terminal("/dev/console", false, true, true, USEC_INFINITY);
-        if (fd < 0) {
-                log_error("Failed to acquire terminal: %s", strerror(-fd));
-                return fd;
-        }
+        if (fd < 0)
+                return log_error_errno(fd, "Failed to acquire terminal: %m");
 
         r = make_stdio(fd);
-        if (r < 0) {
-                log_error("Failed to duplicate terminal fd: %s", strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to duplicate terminal fd: %m");
 
         return 0;
 }
@@ -5440,7 +5634,7 @@ int get_shell(char **_s) {
         return 0;
 }
 
-bool filename_is_safe(const char *p) {
+bool filename_is_valid(const char *p) {
 
         if (isempty(p))
                 return false;
@@ -5771,7 +5965,7 @@ 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);
@@ -6096,85 +6290,48 @@ int split_pair(const char *s, const char *sep, char **l, char **r) {
 }
 
 int shall_restore_state(void) {
-        _cleanup_free_ char *line = NULL;
-        const char *word, *state;
-        size_t l;
+        _cleanup_free_ char *value = NULL;
         int r;
 
-        r = proc_cmdline(&line);
+        r = get_proc_cmdline_key("systemd.restore_state=", &value);
         if (r < 0)
                 return r;
-        if (r == 0) /* Container ... */
-                return 1;
-
-        r = 1;
-
-        FOREACH_WORD_QUOTED(word, l, line, state) {
-                const char *e;
-                char n[l+1];
-                int k;
-
-                memcpy(n, word, l);
-                n[l] = 0;
-
-                e = startswith(n, "systemd.restore_state=");
-                if (!e)
-                        continue;
-
-                k = parse_boolean(e);
-                if (k >= 0)
-                        r = k;
-        }
+        if (r == 0)
+                return true;
 
-        return r;
+        return parse_boolean(value) != 0;
 }
 
 int proc_cmdline(char **ret) {
-        int r;
-
-        if (detect_container(NULL) > 0) {
-                char *buf = NULL, *p;
-                size_t sz = 0;
-
-                r = read_full_file("/proc/1/cmdline", &buf, &sz);
-                if (r < 0)
-                        return r;
-
-                for (p = buf; p + 1 < buf + sz; p++)
-                        if (*p == 0)
-                                *p = ' ';
-
-                *p = 0;
-                *ret = buf;
-                return 1;
-        }
-
-        r = read_one_line_file("/proc/cmdline", ret);
-        if (r < 0)
-                return r;
+        assert(ret);
 
-        return 1;
+        if (detect_container(NULL) > 0)
+                return get_process_cmdline(1, 0, false, ret);
+        else
+                return read_one_line_file("/proc/cmdline", ret);
 }
 
 int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) {
         _cleanup_free_ char *line = NULL;
-        const char *w, *state;
-        size_t l;
+        const char *p;
         int r;
 
         assert(parse_item);
 
         r = proc_cmdline(&line);
         if (r < 0)
-                log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
-        if (r <= 0)
-                return 0;
+                return r;
 
-        FOREACH_WORD_QUOTED(w, l, line, state) {
-                char word[l+1], *value;
+        p = line;
+        for (;;) {
+                _cleanup_free_ char *word = NULL;
+                char *value = NULL;
 
-                memcpy(word, w, l);
-                word[l] = 0;
+                r = unquote_first_word(&p, &word, true);
+                if (r < 0)
+                        return r;
+                if (r == 0)
+                        break;
 
                 /* Filter out arguments that are intended only for the
                  * initrd */
@@ -6193,34 +6350,87 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) {
         return 0;
 }
 
-int container_get_leader(const char *machine, pid_t *pid) {
-        _cleanup_free_ char *s = NULL, *class = NULL;
+int get_proc_cmdline_key(const char *key, char **value) {
+        _cleanup_free_ char *line = NULL, *ret = NULL;
+        bool found = false;
         const char *p;
-        pid_t leader;
         int r;
 
-        assert(machine);
-        assert(pid);
+        assert(key);
 
-        p = strappenda("/run/systemd/machines/", machine);
-        r = parse_env_file(p, NEWLINE, "LEADER", &s, "CLASS", &class, NULL);
-        if (r == -ENOENT)
-                return -EHOSTDOWN;
+        r = proc_cmdline(&line);
         if (r < 0)
                 return r;
-        if (!s)
-                return -EIO;
 
-        if (!streq_ptr(class, "container"))
-                return -EIO;
+        p = line;
+        for (;;) {
+                _cleanup_free_ char *word = NULL;
+                const char *e;
 
-        r = parse_pid(s, &leader);
-        if (r < 0)
-                return r;
-        if (leader <= 1)
-                return -EIO;
+                r = unquote_first_word(&p, &word, true);
+                if (r < 0)
+                        return r;
+                if (r == 0)
+                        break;
 
-        *pid = leader;
+                /* Filter out arguments that are intended only for the
+                 * initrd */
+                if (!in_initrd() && startswith(word, "rd."))
+                        continue;
+
+                if (value) {
+                        e = startswith(word, key);
+                        if (!e)
+                                continue;
+
+                        r = free_and_strdup(&ret, e);
+                        if (r < 0)
+                                return r;
+
+                        found = true;
+                } else {
+                        if (streq(word, key))
+                                found = true;
+                }
+        }
+
+        if (value) {
+                *value = ret;
+                ret = NULL;
+        }
+
+        return found;
+
+}
+
+int container_get_leader(const char *machine, pid_t *pid) {
+        _cleanup_free_ char *s = NULL, *class = NULL;
+        const char *p;
+        pid_t leader;
+        int r;
+
+        assert(machine);
+        assert(pid);
+
+        p = strappenda("/run/systemd/machines/", machine);
+        r = parse_env_file(p, NEWLINE, "LEADER", &s, "CLASS", &class, NULL);
+        if (r == -ENOENT)
+                return -EHOSTDOWN;
+        if (r < 0)
+                return r;
+        if (!s)
+                return -EIO;
+
+        if (!streq_ptr(class, "container"))
+                return -EIO;
+
+        r = parse_pid(s, &leader);
+        if (r < 0)
+                return r;
+        if (leader <= 1)
+                return -EIO;
+
+        *pid = leader;
         return 0;
 }
 
@@ -6363,6 +6573,10 @@ int getpeercred(int fd, struct ucred *ucred) {
          * to namespacing issues */
         if (u.pid <= 0)
                 return -ENODATA;
+        if (u.uid == UID_INVALID)
+                return -ENODATA;
+        if (u.gid == GID_INVALID)
+                return -ENODATA;
 
         *ucred = u;
         return 0;
@@ -6525,23 +6739,6 @@ 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;
@@ -6666,6 +6863,15 @@ 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;
@@ -6700,6 +6906,7 @@ 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)
@@ -6777,7 +6984,11 @@ 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);
@@ -6797,7 +7008,14 @@ 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 */
@@ -6822,42 +7040,61 @@ int fflush_and_check(FILE *f) {
         return 0;
 }
 
-char *tempfn_xxxxxx(const char *p) {
+int tempfn_xxxxxx(const char *p, char **ret) {
         const char *fn;
         char *t;
-        size_t k;
 
         assert(p);
+        assert(ret);
 
-        t = new(char, strlen(p) + 1 + 6 + 1);
-        if (!t)
-                return NULL;
+        /*
+         * Turns this:
+         *         /foo/bar/waldo
+         *
+         * Into this:
+         *         /foo/bar/.#waldoXXXXXX
+         */
 
         fn = basename(p);
-        k = fn - p;
+        if (!filename_is_valid(fn))
+                return -EINVAL;
+
+        t = new(char, strlen(p) + 2 + 6 + 1);
+        if (!t)
+                return -ENOMEM;
 
-        strcpy(stpcpy(stpcpy(mempcpy(t, p, k), "."), fn), "XXXXXX");
+        strcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), "XXXXXX");
 
-        return t;
+        *ret = path_kill_slashes(t);
+        return 0;
 }
 
-char *tempfn_random(const char *p) {
+int tempfn_random(const char *p, char **ret) {
         const char *fn;
         char *t, *x;
         uint64_t u;
-        size_t k;
         unsigned i;
 
         assert(p);
+        assert(ret);
 
-        t = new(char, strlen(p) + 1 + 16 + 1);
-        if (!t)
-                return NULL;
+        /*
+         * Turns this:
+         *         /foo/bar/waldo
+         *
+         * Into this:
+         *         /foo/bar/.#waldobaa2a261115984a9
+         */
 
         fn = basename(p);
-        k = fn - p;
+        if (!filename_is_valid(fn))
+                return -EINVAL;
 
-        x = stpcpy(stpcpy(mempcpy(t, p, k), "."), fn);
+        t = new(char, strlen(p) + 2 + 16 + 1);
+        if (!t)
+                return -ENOMEM;
+
+        x = stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn);
 
         u = random_u64();
         for (i = 0; i < 16; i++) {
@@ -6867,7 +7104,40 @@ char *tempfn_random(const char *p) {
 
         *x = 0;
 
-        return t;
+        *ret = path_kill_slashes(t);
+        return 0;
+}
+
+int tempfn_random_child(const char *p, char **ret) {
+        char *t, *x;
+        uint64_t u;
+        unsigned i;
+
+        assert(p);
+        assert(ret);
+
+        /* Turns this:
+         *         /foo/bar/waldo
+         * Into this:
+         *         /foo/bar/waldo/.#3c2b6219aa75d7d0
+         */
+
+        t = new(char, strlen(p) + 3 + 16 + 1);
+        if (!t)
+                return -ENOMEM;
+
+        x = stpcpy(stpcpy(t, p), "/.#");
+
+        u = random_u64();
+        for (i = 0; i < 16; i++) {
+                *(x++) = hexchar(u & 0xF);
+                u >>= 4;
+        }
+
+        *x = 0;
+
+        *ret = path_kill_slashes(t);
+        return 0;
 }
 
 /* make sure the hostname is not "localhost" */
@@ -6938,19 +7208,19 @@ int is_symlink(const char *path) {
 
 int is_dir(const char* path, bool follow) {
         struct stat st;
+        int r;
 
-        if (follow) {
-                if (stat(path, &st) < 0)
-                        return -errno;
-        } else {
-                if (lstat(path, &st) < 0)
-                        return -errno;
-        }
+        if (follow)
+                r = stat(path, &st);
+        else
+                r = lstat(path, &st);
+        if (r < 0)
+                return -errno;
 
         return !!S_ISDIR(st.st_mode);
 }
 
-int unquote_first_word(const char **p, char **ret) {
+int unquote_first_word(const char **p, char **ret, bool relax) {
         _cleanup_free_ char *s = NULL;
         size_t allocated = 0, sz = 0;
 
@@ -7009,8 +7279,11 @@ int unquote_first_word(const char **p, char **ret) {
                         break;
 
                 case VALUE_ESCAPE:
-                        if (c == 0)
+                        if (c == 0) {
+                                if (relax)
+                                        goto finish;
                                 return -EINVAL;
+                        }
 
                         if (!GREEDY_REALLOC(s, allocated, sz+2))
                                 return -ENOMEM;
@@ -7021,9 +7294,11 @@ int unquote_first_word(const char **p, char **ret) {
                         break;
 
                 case SINGLE_QUOTE:
-                        if (c == 0)
+                        if (c == 0) {
+                                if (relax)
+                                        goto finish;
                                 return -EINVAL;
-                        else if (c == '\'')
+                        else if (c == '\'')
                                 state = VALUE;
                         else if (c == '\\')
                                 state = SINGLE_QUOTE_ESCAPE;
@@ -7037,8 +7312,11 @@ int unquote_first_word(const char **p, char **ret) {
                         break;
 
                 case SINGLE_QUOTE_ESCAPE:
-                        if (c == 0)
+                        if (c == 0) {
+                                if (relax)
+                                        goto finish;
                                 return -EINVAL;
+                        }
 
                         if (!GREEDY_REALLOC(s, allocated, sz+2))
                                 return -ENOMEM;
@@ -7064,8 +7342,11 @@ int unquote_first_word(const char **p, char **ret) {
                         break;
 
                 case DOUBLE_QUOTE_ESCAPE:
-                        if (c == 0)
+                        if (c == 0) {
+                                if (relax)
+                                        goto finish;
                                 return -EINVAL;
+                        }
 
                         if (!GREEDY_REALLOC(s, allocated, sz+2))
                                 return -ENOMEM;
@@ -7125,7 +7406,7 @@ int unquote_many_words(const char **p, ...) {
         l = newa0(char*, n);
         for (c = 0; c < n; c++) {
 
-                r = unquote_first_word(p, &l[c]);
+                r = unquote_first_word(p, &l[c], false);
                 if (r < 0) {
                         int j;
 
@@ -7175,3 +7456,478 @@ int free_and_strdup(char **p, const char *s) {
 
         return 0;
 }
+
+int sethostname_idempotent(const char *s) {
+        int r;
+        char buf[HOST_NAME_MAX + 1] = {};
+
+        assert(s);
+
+        r = gethostname(buf, sizeof(buf));
+        if (r < 0)
+                return -errno;
+
+        if (streq(buf, s))
+                return 0;
+
+        r = sethostname(s, strlen(s));
+        if (r < 0)
+                return -errno;
+
+        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_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
+        if (fd < 0)
+                return -errno;
+
+        return chattr_fd(fd, b, mask);
+}
+
+int read_attr_fd(int fd, unsigned *ret) {
+        assert(fd >= 0);
+
+        if (ioctl(fd, FS_IOC_GETFLAGS, ret) < 0)
+                return -errno;
+
+        return 0;
+}
+
+int read_attr_path(const char *p, unsigned *ret) {
+        _cleanup_close_ int fd = -1;
+
+        assert(p);
+        assert(ret);
+
+        fd = open(p, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
+        if (fd < 0)
+                return -errno;
+
+        return read_attr_fd(fd, ret);
+}
+
+int make_lock_file(const char *p, int operation, LockFile *ret) {
+        _cleanup_close_ int fd = -1;
+        _cleanup_free_ char *t = NULL;
+        int r;
+
+        /*
+         * We use UNPOSIX locks if they are available. They have nice
+         * semantics, and are mostly compatible with NFS. However,
+         * they are only available on new kernels. When we detect we
+         * are running on an older kernel, then we fall back to good
+         * old BSD locks. They also have nice semantics, but are
+         * slightly problematic on NFS, where they are upgraded to
+         * POSIX locks, even though locally they are orthogonal to
+         * POSIX locks.
+         */
+
+        t = strdup(p);
+        if (!t)
+                return -ENOMEM;
+
+        for (;;) {
+                struct flock fl = {
+                        .l_type = (operation & ~LOCK_NB) == LOCK_EX ? F_WRLCK : F_RDLCK,
+                        .l_whence = SEEK_SET,
+                };
+                struct stat st;
+
+                fd = open(p, O_CREAT|O_RDWR|O_NOFOLLOW|O_CLOEXEC|O_NOCTTY, 0600);
+                if (fd < 0)
+                        return -errno;
+
+                r = fcntl(fd, (operation & LOCK_NB) ? F_OFD_SETLK : F_OFD_SETLKW, &fl);
+                if (r < 0) {
+
+                        /* If the kernel is too old, use good old BSD locks */
+                        if (errno == EINVAL)
+                                r = flock(fd, operation);
+
+                        if (r < 0)
+                                return errno == EAGAIN ? -EBUSY : -errno;
+                }
+
+                /* If we acquired the lock, let's check if the file
+                 * still exists in the file system. If not, then the
+                 * previous exclusive owner removed it and then closed
+                 * it. In such a case our acquired lock is worthless,
+                 * hence try again. */
+
+                r = fstat(fd, &st);
+                if (r < 0)
+                        return -errno;
+                if (st.st_nlink > 0)
+                        break;
+
+                fd = safe_close(fd);
+        }
+
+        ret->path = t;
+        ret->fd = fd;
+        ret->operation = operation;
+
+        fd = -1;
+        t = NULL;
+
+        return r;
+}
+
+int make_lock_file_for(const char *p, int operation, LockFile *ret) {
+        const char *fn;
+        char *t;
+
+        assert(p);
+        assert(ret);
+
+        fn = basename(p);
+        if (!filename_is_valid(fn))
+                return -EINVAL;
+
+        t = newa(char, strlen(p) + 2 + 4 + 1);
+        stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), ".lck");
+
+        return make_lock_file(t, operation, ret);
+}
+
+void release_lock_file(LockFile *f) {
+        int r;
+
+        if (!f)
+                return;
+
+        if (f->path) {
+
+                /* If we are the exclusive owner we can safely delete
+                 * the lock file itself. If we are not the exclusive
+                 * owner, we can try becoming it. */
+
+                if (f->fd >= 0 &&
+                    (f->operation & ~LOCK_NB) == LOCK_SH) {
+                        static const struct flock fl = {
+                                .l_type = F_WRLCK,
+                                .l_whence = SEEK_SET,
+                        };
+
+                        r = fcntl(f->fd, F_OFD_SETLK, &fl);
+                        if (r < 0 && errno == EINVAL)
+                                r = flock(f->fd, LOCK_EX|LOCK_NB);
+
+                        if (r >= 0)
+                                f->operation = LOCK_EX|LOCK_NB;
+                }
+
+                if ((f->operation & ~LOCK_NB) == LOCK_EX)
+                        unlink_noerrno(f->path);
+
+                free(f->path);
+                f->path = NULL;
+        }
+
+        f->fd = safe_close(f->fd);
+        f->operation = 0;
+}