chiark / gitweb /
util: fix build
[elogind.git] / src / util.c
index 2047ebd7bd841bd8b045c86258327dab81f4fcf4..e5b5e53f7e1c8a5c19cc1e75539b5c2cf96eab3d 100644 (file)
@@ -53,6 +53,9 @@
 #include <sys/capability.h>
 #include <sys/time.h>
 #include <linux/rtc.h>
+#include <glob.h>
+#include <grp.h>
+#include <sys/mman.h>
 
 #include "macro.h"
 #include "util.h"
 #include "exit-status.h"
 #include "hashmap.h"
 
+int saved_argc = 0;
+char **saved_argv = NULL;
+
 size_t page_size(void) {
         static __thread size_t pgsz = 0;
         long r;
 
-        if (pgsz)
+        if (_likely_(pgsz > 0))
                 return pgsz;
 
         assert_se((r = sysconf(_SC_PAGESIZE)) > 0);
@@ -108,6 +114,28 @@ dual_timestamp* dual_timestamp_get(dual_timestamp *ts) {
         return ts;
 }
 
+dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u) {
+        int64_t delta;
+        assert(ts);
+
+        ts->realtime = u;
+
+        if (u == 0)
+                ts->monotonic = 0;
+        else {
+                delta = (int64_t) now(CLOCK_REALTIME) - (int64_t) u;
+
+                ts->monotonic = now(CLOCK_MONOTONIC);
+
+                if ((int64_t) ts->monotonic > delta)
+                        ts->monotonic -= delta;
+                else
+                        ts->monotonic = 0;
+        }
+
+        return ts;
+}
+
 usec_t timespec_load(const struct timespec *ts) {
         assert(ts);
 
@@ -291,6 +319,26 @@ int parse_pid(const char *s, pid_t* ret_pid) {
         return 0;
 }
 
+int parse_uid(const char *s, uid_t* ret_uid) {
+        unsigned long ul = 0;
+        uid_t uid;
+        int r;
+
+        assert(s);
+        assert(ret_uid);
+
+        if ((r = safe_atolu(s, &ul)) < 0)
+                return r;
+
+        uid = (uid_t) ul;
+
+        if ((unsigned long) uid != ul)
+                return -ERANGE;
+
+        *ret_uid = uid;
+        return 0;
+}
+
 int safe_atou(const char *s, unsigned *ret_u) {
         char *x = NULL;
         unsigned long l;
@@ -465,7 +513,7 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
         assert_se(snprintf(fn, sizeof(fn)-1, "/proc/%lu/stat", (unsigned long) pid) < (int) (sizeof(fn)-1));
         char_array_0(fn);
 
-        if (!(f = fopen(fn, "r")))
+        if (!(f = fopen(fn, "re")))
                 return -errno;
 
         if (!(fgets(line, sizeof(line), f))) {
@@ -510,7 +558,7 @@ int get_starttime_of_pid(pid_t pid, unsigned long long *st) {
         assert_se(snprintf(fn, sizeof(fn)-1, "/proc/%lu/stat", (unsigned long) pid) < (int) (sizeof(fn)-1));
         char_array_0(fn);
 
-        if (!(f = fopen(fn, "r")))
+        if (!(f = fopen(fn, "re")))
                 return -errno;
 
         if (!(fgets(line, sizeof(line), f))) {
@@ -735,13 +783,7 @@ int read_full_file(const char *fn, char **contents, size_t *size) {
                 }
         }
 
-        if (buf)
-                buf[l] = 0;
-        else if (!(buf = calloc(1, 1))) {
-                r = -errno;
-                goto finish;
-        }
-
+        buf[l] = 0;
         *contents = buf;
         buf = NULL;
 
@@ -762,7 +804,7 @@ int parse_env_file(
                 const char *separator, ...) {
 
         int r = 0;
-        char *contents, *p;
+        char *contents = NULL, *p;
 
         assert(fname);
         assert(separator);
@@ -952,46 +994,51 @@ char *truncate_nl(char *s) {
         return s;
 }
 
-int get_process_name(pid_t pid, char **name) {
-        char *p;
+int get_process_comm(pid_t pid, char **name) {
         int r;
 
-        assert(pid >= 1);
         assert(name);
 
-        if (asprintf(&p, "/proc/%lu/comm", (unsigned long) pid) < 0)
-                return -ENOMEM;
-
-        r = read_one_line_file(p, name);
-        free(p);
+        if (pid == 0)
+                r = read_one_line_file("/proc/self/comm", name);
+        else {
+                char *p;
+                if (asprintf(&p, "/proc/%lu/comm", (unsigned long) pid) < 0)
+                        return -ENOMEM;
 
-        if (r < 0)
-                return r;
+                r = read_one_line_file(p, name);
+                free(p);
+        }
 
-        return 0;
+        return r;
 }
 
-int get_process_cmdline(pid_t pid, size_t max_length, char **line) {
-        char *p, *r, *k;
+int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line) {
+        char *r, *k;
         int c;
         bool space = false;
         size_t left;
         FILE *f;
 
-        assert(pid >= 1);
         assert(max_length > 0);
         assert(line);
 
-        if (asprintf(&p, "/proc/%lu/cmdline", (unsigned long) pid) < 0)
-                return -ENOMEM;
+        if (pid == 0)
+                f = fopen("/proc/self/cmdline", "re");
+        else {
+                char *p;
+                if (asprintf(&p, "/proc/%lu/cmdline", (unsigned long) pid) < 0)
+                        return -ENOMEM;
 
-        f = fopen(p, "r");
-        free(p);
+                f = fopen(p, "re");
+                free(p);
+        }
 
         if (!f)
                 return -errno;
 
-        if (!(r = new(char, max_length))) {
+        r = new(char, max_length);
+        if (!r) {
                 fclose(f);
                 return -ENOMEM;
         }
@@ -1035,13 +1082,17 @@ int get_process_cmdline(pid_t pid, size_t max_length, char **line) {
 
                 free(r);
 
-                if ((h = get_process_name(pid, &t)) < 0)
+                if (!comm_fallback)
+                        return -ENOENT;
+
+                h = get_process_comm(pid, &t);
+                if (h < 0)
                         return h;
 
-                h = asprintf(&r, "[%s]", t);
+                r = join("[", t, "]", NULL);
                 free(t);
 
-                if (h < 0)
+                if (!r)
                         return -ENOMEM;
         }
 
@@ -1049,6 +1100,25 @@ int get_process_cmdline(pid_t pid, size_t max_length, char **line) {
         return 0;
 }
 
+int get_process_exe(pid_t pid, char **name) {
+        int r;
+
+        assert(name);
+
+        if (pid == 0)
+                r = readlink_malloc("/proc/self/exe", name);
+        else {
+                char *p;
+                if (asprintf(&p, "/proc/%lu/exe", (unsigned long) pid) < 0)
+                        return -ENOMEM;
+
+                r = readlink_malloc(p, name);
+                free(p);
+        }
+
+        return r;
+}
+
 char *strnappend(const char *s, const char *suffix, size_t b) {
         size_t a;
         char *r;
@@ -1131,6 +1201,29 @@ int readlink_and_make_absolute(const char *p, char **r) {
         return 0;
 }
 
+int readlink_and_canonicalize(const char *p, char **r) {
+        char *t, *s;
+        int j;
+
+        assert(p);
+        assert(r);
+
+        j = readlink_and_make_absolute(p, &t);
+        if (j < 0)
+                return j;
+
+        s = canonicalize_file_name(t);
+        if (s) {
+                free(t);
+                *r = s;
+        } else
+                *r = t;
+
+        path_kill_slashes(*r);
+
+        return 0;
+}
+
 int parent_of_path(const char *path, char **_r) {
         const char *e, *a = NULL, *b = NULL, *p;
         char *r;
@@ -1196,8 +1289,6 @@ bool is_path(const char *p) {
 }
 
 char *path_make_absolute(const char *p, const char *prefix) {
-        char *r;
-
         assert(p);
 
         /* Makes every item in the list an absolute path by prepending
@@ -1206,10 +1297,7 @@ char *path_make_absolute(const char *p, const char *prefix) {
         if (path_is_absolute(p) || !prefix)
                 return strdup(p);
 
-        if (asprintf(&r, "%s/%s", prefix, p) < 0)
-                return NULL;
-
-        return r;
+        return join(prefix, "/", p, NULL);
 }
 
 char *path_make_absolute_cwd(const char *p) {
@@ -1341,21 +1429,18 @@ int reset_all_signal_handlers(void) {
 }
 
 char *strstrip(char *s) {
-        char *e, *l = NULL;
+        char *e;
 
         /* Drops trailing whitespace. Modifies the string in
          * place. Returns pointer to first non-space character */
 
         s += strspn(s, WHITESPACE);
 
-        for (e = s; *e; e++)
-                if (!strchr(WHITESPACE, *e))
-                        l = e;
+        for (e = strchr(s, 0); e > s; e --)
+                if (!strchr(WHITESPACE, e[-1]))
+                        break;
 
-        if (l)
-                *(l+1) = 0;
-        else
-                *s = 0;
+        *e = 0;
 
         return s;
 }
@@ -1377,6 +1462,19 @@ char *delete_chars(char *s, const char *bad) {
         return s;
 }
 
+bool in_charset(const char *s, const char* charset) {
+        const char *i;
+
+        assert(s);
+        assert(charset);
+
+        for (i = s; *i; i++)
+                if (!strchr(charset, *i))
+                        return false;
+
+        return true;
+}
+
 char *file_in_same_dir(const char *path, const char *filename) {
         char *e, *r;
         size_t k;
@@ -2238,8 +2336,10 @@ int chvt(int vt) {
                         0
                 };
 
-                if (ioctl(fd, TIOCLINUX, tiocl) < 0)
-                        return -errno;
+                if (ioctl(fd, TIOCLINUX, tiocl) < 0) {
+                        r = -errno;
+                        goto fail;
+                }
 
                 vt = tiocl[0] <= 0 ? 1 : tiocl[0];
         }
@@ -2247,7 +2347,8 @@ int chvt(int vt) {
         if (ioctl(fd, VT_ACTIVATE, vt) < 0)
                 r = -errno;
 
-        close_nointr_nofail(r);
+fail:
+        close_nointr_nofail(fd);
         return r;
 }
 
@@ -2631,7 +2732,7 @@ int release_terminal(void) {
         int r = 0, fd;
         struct sigaction sa_old, sa_new;
 
-        if ((fd = open("/dev/tty", O_RDWR|O_NOCTTY|O_NDELAY)) < 0)
+        if ((fd = open("/dev/tty", O_RDWR|O_NOCTTY|O_NDELAY|O_CLOEXEC)) < 0)
                 return -errno;
 
         /* Temporarily ignore SIGHUP, so that we don't get SIGHUP'ed
@@ -2820,19 +2921,25 @@ ssize_t loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) {
         return n;
 }
 
-int path_is_mount_point(const char *t) {
+int path_is_mount_point(const char *t, bool allow_symlink) {
         struct stat a, b;
         char *parent;
         int r;
 
-        if (lstat(t, &a) < 0) {
+        if (allow_symlink)
+                r = stat(t, &a);
+        else
+                r = lstat(t, &a);
+
+        if (r < 0) {
                 if (errno == ENOENT)
                         return 0;
 
                 return -errno;
         }
 
-        if ((r = parent_of_path(t, &parent)) < 0)
+        r = parent_of_path(t, &parent);
+        if (r < 0)
                 return r;
 
         r = lstat(parent, &b);
@@ -2907,6 +3014,62 @@ int parse_usec(const char *t, usec_t *usec) {
         return 0;
 }
 
+int parse_bytes(const char *t, off_t *bytes) {
+        static const struct {
+                const char *suffix;
+                off_t factor;
+        } table[] = {
+                { "B", 1 },
+                { "K", 1024ULL },
+                { "M", 1024ULL*1024ULL },
+                { "G", 1024ULL*1024ULL*1024ULL },
+                { "T", 1024ULL*1024ULL*1024ULL*1024ULL },
+                { "", 1 },
+        };
+
+        const char *p;
+        off_t r = 0;
+
+        assert(t);
+        assert(bytes);
+
+        p = t;
+        do {
+                long long l;
+                char *e;
+                unsigned i;
+
+                errno = 0;
+                l = strtoll(p, &e, 10);
+
+                if (errno != 0)
+                        return -errno;
+
+                if (l < 0)
+                        return -ERANGE;
+
+                if (e == p)
+                        return -EINVAL;
+
+                e += strspn(e, WHITESPACE);
+
+                for (i = 0; i < ELEMENTSOF(table); i++)
+                        if (startswith(e, table[i].suffix)) {
+                                r += (off_t) l * table[i].factor;
+                                p = e + strlen(table[i].suffix);
+                                break;
+                        }
+
+                if (i >= ELEMENTSOF(table))
+                        return -EINVAL;
+
+        } while (*p != 0);
+
+        *bytes = r;
+
+        return 0;
+}
+
 int make_stdio(int fd) {
         int r, s, t;
 
@@ -2922,6 +3085,10 @@ int make_stdio(int fd) {
         if (r < 0 || s < 0 || t < 0)
                 return -errno;
 
+        fd_cloexec(STDIN_FILENO, false);
+        fd_cloexec(STDOUT_FILENO, false);
+        fd_cloexec(STDERR_FILENO, false);
+
         return 0;
 }
 
@@ -3004,6 +3171,20 @@ void rename_process(const char name[8]) {
 
         if (program_invocation_name)
                 strncpy(program_invocation_name, name, strlen(program_invocation_name));
+
+        if (saved_argc > 0) {
+                int i;
+
+                if (saved_argv[0])
+                        strncpy(saved_argv[0], name, strlen(saved_argv[0]));
+
+                for (i = 1; i < saved_argc; i++) {
+                        if (!saved_argv[i])
+                                break;
+
+                        memset(saved_argv[i], 0, strlen(saved_argv[i]));
+                }
+        }
 }
 
 void sigset_add_many(sigset_t *ss, ...) {
@@ -3092,23 +3273,28 @@ int getttyname_harder(int fd, char **r) {
 
         if (streq(s, "tty")) {
                 free(s);
-                return get_ctty(r, NULL);
+                return get_ctty(0, NULL, r);
         }
 
         *r = s;
         return 0;
 }
 
-int get_ctty_devnr(dev_t *d) {
+int get_ctty_devnr(pid_t pid, dev_t *d) {
         int k;
-        char line[LINE_MAX], *p;
+        char line[LINE_MAX], *p, *fn;
         unsigned long ttynr;
         FILE *f;
 
-        if (!(f = fopen("/proc/self/stat", "r")))
+        if (asprintf(&fn, "/proc/%lu/stat", (unsigned long) (pid <= 0 ? getpid() : pid)) < 0)
+                return -ENOMEM;
+
+        f = fopen(fn, "re");
+        free(fn);
+        if (!f)
                 return -errno;
 
-        if (!(fgets(line, sizeof(line), f))) {
+        if (!fgets(line, sizeof(line), f)) {
                 k = -errno;
                 fclose(f);
                 return k;
@@ -3116,7 +3302,8 @@ int get_ctty_devnr(dev_t *d) {
 
         fclose(f);
 
-        if (!(p = strrchr(line, ')')))
+        p = strrchr(line, ')');
+        if (!p)
                 return -EIO;
 
         p++;
@@ -3134,14 +3321,15 @@ int get_ctty_devnr(dev_t *d) {
         return 0;
 }
 
-int get_ctty(char **r, dev_t *_devnr) {
+int get_ctty(pid_t pid, dev_t *_devnr, char **r) {
         int k;
         char fn[PATH_MAX], *s, *b, *p;
         dev_t devnr;
 
         assert(r);
 
-        if ((k = get_ctty_devnr(&devnr)) < 0)
+        k = get_ctty_devnr(pid, &devnr);
+        if (k < 0)
                 return k;
 
         snprintf(fn, sizeof(fn), "/dev/char/%u:%u", major(devnr), minor(devnr));
@@ -3198,7 +3386,7 @@ int get_ctty(char **r, dev_t *_devnr) {
         return 0;
 }
 
-static int rm_rf_children(int fd, bool only_dirs) {
+static int rm_rf_children(int fd, bool only_dirs, bool honour_sticky) {
         DIR *d;
         int ret = 0;
 
@@ -3215,7 +3403,7 @@ static int rm_rf_children(int fd, bool only_dirs) {
 
         for (;;) {
                 struct dirent buf, *de;
-                bool is_dir;
+                bool is_dir, keep_around = false;
                 int r;
 
                 if ((r = readdir_r(d, &buf, &de)) != 0) {
@@ -3239,9 +3427,26 @@ static int rm_rf_children(int fd, bool only_dirs) {
                                 continue;
                         }
 
+                        if (honour_sticky)
+                                keep_around = st.st_uid == 0 && (st.st_mode & S_ISVTX);
+
                         is_dir = S_ISDIR(st.st_mode);
-                } else
+
+                } else {
+                        if (honour_sticky) {
+                                struct stat st;
+
+                                if (fstatat(fd, de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
+                                        if (ret == 0 && errno != ENOENT)
+                                                ret = -errno;
+                                        continue;
+                                }
+
+                                keep_around = st.st_uid == 0 && (st.st_mode & S_ISVTX);
+                        }
+
                         is_dir = de->d_type == DT_DIR;
+                }
 
                 if (is_dir) {
                         int subdir_fd;
@@ -3252,16 +3457,18 @@ static int rm_rf_children(int fd, bool only_dirs) {
                                 continue;
                         }
 
-                        if ((r = rm_rf_children(subdir_fd, only_dirs)) < 0) {
+                        if ((r = rm_rf_children(subdir_fd, only_dirs, honour_sticky)) < 0) {
                                 if (ret == 0)
                                         ret = r;
                         }
 
-                        if (unlinkat(fd, de->d_name, AT_REMOVEDIR) < 0) {
-                                if (ret == 0 && errno != ENOENT)
-                                        ret = -errno;
-                        }
-                } else  if (!only_dirs) {
+                        if (!keep_around)
+                                if (unlinkat(fd, de->d_name, AT_REMOVEDIR) < 0) {
+                                        if (ret == 0 && errno != ENOENT)
+                                                ret = -errno;
+                                }
+
+                } else if (!only_dirs && !keep_around) {
 
                         if (unlinkat(fd, de->d_name, 0) < 0) {
                                 if (ret == 0 && errno != ENOENT)
@@ -3275,7 +3482,7 @@ static int rm_rf_children(int fd, bool only_dirs) {
         return ret;
 }
 
-int rm_rf(const char *path, bool only_dirs, bool delete_root) {
+int rm_rf(const char *path, bool only_dirs, bool delete_root, bool honour_sticky) {
         int fd;
         int r;
 
@@ -3293,13 +3500,18 @@ int rm_rf(const char *path, bool only_dirs, bool delete_root) {
                 return 0;
         }
 
-        r = rm_rf_children(fd, only_dirs);
+        r = rm_rf_children(fd, only_dirs, honour_sticky);
+
+        if (delete_root) {
+
+                if (honour_sticky && file_is_sticky(path) > 0)
+                        return r;
 
-        if (delete_root)
-                if (rmdir(path) < 0) {
+                if (rmdir(path) < 0 && errno != ENOENT) {
                         if (r == 0)
                                 r = -errno;
                 }
+        }
 
         return r;
 }
@@ -3320,6 +3532,22 @@ int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid) {
         return 0;
 }
 
+int fchmod_and_fchown(int fd, mode_t mode, uid_t uid, gid_t gid) {
+        assert(fd >= 0);
+
+        /* Under the assumption that we are running privileged we
+         * first change the access mode and only then hand out
+         * ownership to avoid a window where access is too open. */
+
+        if (fchmod(fd, mode) < 0)
+                return -errno;
+
+        if (fchown(fd, uid, gid) < 0)
+                return -errno;
+
+        return 0;
+}
+
 cpu_set_t* cpu_set_malloc(unsigned *ncpus) {
         cpu_set_t *r;
         unsigned n = 1024;
@@ -3681,7 +3909,7 @@ int columns(void) {
         static __thread int parsed_columns = 0;
         const char *e;
 
-        if (parsed_columns > 0)
+        if (_likely_(parsed_columns > 0))
                 return parsed_columns;
 
         if ((e = getenv("COLUMNS")))
@@ -3815,8 +4043,12 @@ char *normalize_env_assignment(const char *s) {
 }
 
 int wait_for_terminate(pid_t pid, siginfo_t *status) {
+        siginfo_t dummy;
+
         assert(pid >= 1);
-        assert(status);
+
+        if (!status)
+                status = &dummy;
 
         for (;;) {
                 zero(*status);
@@ -3889,6 +4121,17 @@ bool null_or_empty(struct stat *st) {
         return false;
 }
 
+int null_or_empty_path(const char *fn) {
+        struct stat st;
+
+        assert(fn);
+
+        if (stat(fn, &st) < 0)
+                return -errno;
+
+        return null_or_empty(&st);
+}
+
 DIR *xopendirat(int fd, const char *name, int flags) {
         int nfd;
         DIR *d;
@@ -4018,8 +4261,31 @@ bool tty_is_vc(const char *tty) {
         if (startswith(tty, "/dev/"))
                 tty += 5;
 
-        return startswith(tty, "tty") &&
-                tty[3] >= '0' && tty[3] <= '9';
+        return vtnr_from_tty(tty) >= 0;
+}
+
+int vtnr_from_tty(const char *tty) {
+        int i, r;
+
+        assert(tty);
+
+        if (startswith(tty, "/dev/"))
+                tty += 5;
+
+        if (!startswith(tty, "tty") )
+                return -EINVAL;
+
+        if (tty[3] < '0' || tty[3] > '9')
+                return -EINVAL;
+
+        r = safe_atoi(tty+3, &i);
+        if (r < 0)
+                return r;
+
+        if (i < 0 || i > 63)
+                return -EINVAL;
+
+        return i;
 }
 
 const char *default_term_for_tty(const char *tty) {
@@ -4049,253 +4315,44 @@ const char *default_term_for_tty(const char *tty) {
         return term;
 }
 
-/* Returns a short identifier for the various VM implementations */
-int detect_vm(const char **id) {
-
-#if defined(__i386__) || defined(__x86_64__)
+bool dirent_is_file(const struct dirent *de) {
+        assert(de);
 
-        /* Both CPUID and DMI are x86 specific interfaces... */
+        if (ignore_file(de->d_name))
+                return false;
 
-        static const char *const dmi_vendors[] = {
-                "/sys/class/dmi/id/sys_vendor",
-                "/sys/class/dmi/id/board_vendor",
-                "/sys/class/dmi/id/bios_vendor"
-        };
+        if (de->d_type != DT_REG &&
+            de->d_type != DT_LNK &&
+            de->d_type != DT_UNKNOWN)
+                return false;
 
-        static const char dmi_vendor_table[] =
-                "QEMU\0"                  "qemu\0"
-                /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
-                "VMware\0"                "vmware\0"
-                "VMW\0"                   "vmware\0"
-                "Microsoft Corporation\0" "microsoft\0"
-                "innotek GmbH\0"          "oracle\0"
-                "Xen\0"                   "xen\0"
-                "Bochs\0"                 "bochs\0";
-
-        static const char cpuid_vendor_table[] =
-                "XenVMMXenVMM\0"          "xen\0"
-                "KVMKVMKVM\0"             "kvm\0"
-                /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
-                "VMwareVMware\0"          "vmware\0"
-                /* http://msdn.microsoft.com/en-us/library/ff542428.aspx */
-                "Microsoft Hv\0"          "microsoft\0";
-
-        uint32_t eax, ecx;
-        union {
-                uint32_t sig32[3];
-                char text[13];
-        } sig;
-        unsigned i;
-        const char *j, *k;
-        bool hypervisor;
-
-        /* http://lwn.net/Articles/301888/ */
-        zero(sig);
-
-#if defined (__i386__)
-#define REG_a "eax"
-#define REG_b "ebx"
-#elif defined (__amd64__)
-#define REG_a "rax"
-#define REG_b "rbx"
-#endif
+        return true;
+}
 
-        /* First detect whether there is a hypervisor */
-        eax = 1;
-        __asm__ __volatile__ (
-                /* ebx/rbx is being used for PIC! */
-                "  push %%"REG_b"         \n\t"
-                "  cpuid                  \n\t"
-                "  pop %%"REG_b"          \n\t"
+bool dirent_is_file_with_suffix(const struct dirent *de, const char *suffix) {
+        assert(de);
 
-                : "=a" (eax), "=c" (ecx)
-                : "0" (eax)
-        );
+        if (!dirent_is_file(de))
+                return false;
 
-        hypervisor = !!(ecx & 0x80000000U);
+        return endswith(de->d_name, suffix);
+}
 
-        if (hypervisor) {
+void execute_directory(const char *directory, DIR *d, char *argv[]) {
+        DIR *_d = NULL;
+        struct dirent *de;
+        Hashmap *pids = NULL;
 
-                /* There is a hypervisor, see what it is */
-                eax = 0x40000000U;
-                __asm__ __volatile__ (
-                        /* ebx/rbx is being used for PIC! */
-                        "  push %%"REG_b"         \n\t"
-                        "  cpuid                  \n\t"
-                        "  mov %%ebx, %1          \n\t"
-                        "  pop %%"REG_b"          \n\t"
+        assert(directory);
 
-                        : "=a" (eax), "=r" (sig.sig32[0]), "=c" (sig.sig32[1]), "=d" (sig.sig32[2])
-                        : "0" (eax)
-                );
+        /* Executes all binaries in a directory in parallel and waits
+         * until all they all finished. */
 
-                NULSTR_FOREACH_PAIR(j, k, cpuid_vendor_table)
-                        if (streq(sig.text, j)) {
+        if (!d) {
+                if (!(_d = opendir(directory))) {
 
-                                if (id)
-                                        *id = k;
-
-                                return 1;
-                        }
-        }
-
-        for (i = 0; i < ELEMENTSOF(dmi_vendors); i++) {
-                char *s;
-                int r;
-                const char *found = NULL;
-
-                if ((r = read_one_line_file(dmi_vendors[i], &s)) < 0) {
-                        if (r != -ENOENT)
-                                return r;
-
-                        continue;
-                }
-
-                NULSTR_FOREACH_PAIR(j, k, dmi_vendor_table)
-                        if (startswith(s, j))
-                                found = k;
-                free(s);
-
-                if (found) {
-                        if (id)
-                                *id = found;
-
-                        return 1;
-                }
-        }
-
-        if (hypervisor) {
-                if (id)
-                        *id = "other";
-
-                return 1;
-        }
-
-#endif
-        return 0;
-}
-
-int detect_container(const char **id) {
-        FILE *f;
-
-        /* Unfortunately many of these operations require root access
-         * in one way or another */
-
-        if (geteuid() != 0)
-                return -EPERM;
-
-        if (running_in_chroot() > 0) {
-
-                if (id)
-                        *id = "chroot";
-
-                return 1;
-        }
-
-        /* /proc/vz exists in container and outside of the container,
-         * /proc/bc only outside of the container. */
-        if (access("/proc/vz", F_OK) >= 0 &&
-            access("/proc/bc", F_OK) < 0) {
-
-                if (id)
-                        *id = "openvz";
-
-                return 1;
-        }
-
-        if ((f = fopen("/proc/self/cgroup", "r"))) {
-
-                for (;;) {
-                        char line[LINE_MAX], *p;
-
-                        if (!fgets(line, sizeof(line), f))
-                                break;
-
-                        if (!(p = strchr(strstrip(line), ':')))
-                                continue;
-
-                        if (strncmp(p, ":ns:", 4))
-                                continue;
-
-                        if (!streq(p, ":ns:/")) {
-                                fclose(f);
-
-                                if (id)
-                                        *id = "pidns";
-
-                                return 1;
-                        }
-                }
-
-                fclose(f);
-        }
-
-        return 0;
-}
-
-/* Returns a short identifier for the various VM/container implementations */
-int detect_virtualization(const char **id) {
-        static __thread const char *cached_id = NULL;
-        const char *_id;
-        int r;
-
-        if (cached_id) {
-
-                if (cached_id == (const char*) -1)
-                        return 0;
-
-                if (id)
-                        *id = cached_id;
-
-                return 1;
-        }
-
-        if ((r = detect_container(&_id)) != 0)
-                goto finish;
-
-        r = detect_vm(&_id);
-
-finish:
-        if (r > 0) {
-                cached_id = _id;
-
-                if (id)
-                        *id = _id;
-        } else if (r == 0)
-                cached_id = (const char*) -1;
-
-        return r;
-}
-
-bool dirent_is_file(struct dirent *de) {
-        assert(de);
-
-        if (ignore_file(de->d_name))
-                return false;
-
-        if (de->d_type != DT_REG &&
-            de->d_type != DT_LNK &&
-            de->d_type != DT_UNKNOWN)
-                return false;
-
-        return true;
-}
-
-void execute_directory(const char *directory, DIR *d, char *argv[]) {
-        DIR *_d = NULL;
-        struct dirent *de;
-        Hashmap *pids = NULL;
-
-        assert(directory);
-
-        /* Executes all binaries in a directory in parallel and waits
-         * until all they all finished. */
-
-        if (!d) {
-                if (!(_d = opendir(directory))) {
-
-                        if (errno == ENOENT)
-                                return;
+                        if (errno == ENOENT)
+                                return;
 
                         log_error("Failed to enumerate directory %s: %m", directory);
                         return;
@@ -4453,6 +4510,98 @@ void parse_syslog_priority(char **p, int *priority) {
         *p += k;
 }
 
+void skip_syslog_pid(char **buf) {
+        char *p;
+
+        assert(buf);
+        assert(*buf);
+
+        p = *buf;
+
+        if (*p != '[')
+                return;
+
+        p++;
+        p += strspn(p, "0123456789");
+
+        if (*p != ']')
+                return;
+
+        p++;
+
+        *buf = p;
+}
+
+void skip_syslog_date(char **buf) {
+        enum {
+                LETTER,
+                SPACE,
+                NUMBER,
+                SPACE_OR_NUMBER,
+                COLON
+        } sequence[] = {
+                LETTER, LETTER, LETTER,
+                SPACE,
+                SPACE_OR_NUMBER, NUMBER,
+                SPACE,
+                SPACE_OR_NUMBER, NUMBER,
+                COLON,
+                SPACE_OR_NUMBER, NUMBER,
+                COLON,
+                SPACE_OR_NUMBER, NUMBER,
+                SPACE
+        };
+
+        char *p;
+        unsigned i;
+
+        assert(buf);
+        assert(*buf);
+
+        p = *buf;
+
+        for (i = 0; i < ELEMENTSOF(sequence); i++, p++) {
+
+                if (!*p)
+                        return;
+
+                switch (sequence[i]) {
+
+                case SPACE:
+                        if (*p != ' ')
+                                return;
+                        break;
+
+                case SPACE_OR_NUMBER:
+                        if (*p == ' ')
+                                break;
+
+                        /* fall through */
+
+                case NUMBER:
+                        if (*p < '0' || *p > '9')
+                                return;
+
+                        break;
+
+                case LETTER:
+                        if (!(*p >= 'A' && *p <= 'Z') &&
+                            !(*p >= 'a' && *p <= 'z'))
+                                return;
+
+                        break;
+
+                case COLON:
+                        if (*p != ':')
+                                return;
+                        break;
+
+                }
+        }
+
+        *buf = p;
+}
+
 int have_effective_cap(int value) {
         cap_t cap;
         cap_flag_value_t fv;
@@ -4622,7 +4771,11 @@ int vt_disallocate(const char *name) {
                 if (fd < 0)
                         return fd;
 
-                loop_write(fd, "\033[H\033[2J", 7, false); /* clear screen */
+                loop_write(fd,
+                           "\033[r"    /* clear scrolling region */
+                           "\033[H"    /* move home */
+                           "\033[2J",  /* clear screen */
+                           10, false);
                 close_nointr_nofail(fd);
 
                 return 0;
@@ -4658,31 +4811,19 @@ int vt_disallocate(const char *name) {
         if (fd < 0)
                 return fd;
 
-        /* Requires Linux 2.6.40 */
-        loop_write(fd, "\033[H\033[3J", 7, false); /* clear screen including scrollback */
+        loop_write(fd,
+                   "\033[r"   /* clear scrolling region */
+                   "\033[H"   /* move home */
+                   "\033[3J", /* clear screen including scrollback, requires Linux 2.6.40 */
+                   10, false);
         close_nointr_nofail(fd);
 
         return 0;
 }
 
-
-static int file_is_conf(const struct dirent *d, const char *suffix) {
-        assert(d);
-
-        if (ignore_file(d->d_name))
-                return 0;
-
-        if (d->d_type != DT_REG &&
-            d->d_type != DT_LNK &&
-            d->d_type != DT_UNKNOWN)
-                return 0;
-
-        return endswith(d->d_name, suffix);
-}
-
 static int files_add(Hashmap *h, const char *path, const char *suffix) {
         DIR *dir;
-        struct dirent *de;
+        struct dirent buffer, *de;
         int r = 0;
 
         dir = opendir(path);
@@ -4692,11 +4833,20 @@ static int files_add(Hashmap *h, const char *path, const char *suffix) {
                 return -errno;
         }
 
-        for (de = readdir(dir); de; de = readdir(dir)) {
+        for (;;) {
+                int k;
                 char *p, *f;
-                const char *base;
 
-                if (!file_is_conf(de, suffix))
+                k = readdir_r(dir, &buffer, &de);
+                if (k != 0) {
+                        r = -k;
+                        goto finish;
+                }
+
+                if (!de)
+                        break;
+
+                if (!dirent_is_file_with_suffix(de, suffix))
                         continue;
 
                 if (asprintf(&p, "%s/%s", path, de->d_name) < 0) {
@@ -4713,8 +4863,7 @@ static int files_add(Hashmap *h, const char *path, const char *suffix) {
                 free(p);
 
                 log_debug("found: %s\n", f);
-                base = f + strlen(path) + 1;
-                if (hashmap_put(h, base, f) <= 0)
+                if (hashmap_put(h, file_name_from_path(f), f) <= 0)
                         free(f);
         }
 
@@ -4820,7 +4969,7 @@ int hwclock_is_localtime(void) {
         return local;
 }
 
-int hwclock_apply_localtime_delta(void) {
+int hwclock_apply_localtime_delta(int *min) {
         const struct timeval *tv_null = NULL;
         struct timespec ts;
         struct tm *tm;
@@ -4841,8 +4990,9 @@ int hwclock_apply_localtime_delta(void) {
          */
         if (settimeofday(tv_null, &tz) < 0)
                 return -errno;
-
-        return minuteswest;
+        if (min)
+                *min = minuteswest;
+        return 0;
 }
 
 int hwclock_reset_localtime_delta(void) {
@@ -5046,6 +5196,493 @@ int symlink_or_copy_atomic(const char *from, const char *to) {
         return r;
 }
 
+int audit_session_from_pid(pid_t pid, uint32_t *id) {
+        char *s;
+        uint32_t u;
+        int r;
+
+        assert(id);
+
+        if (have_effective_cap(CAP_AUDIT_CONTROL) <= 0)
+                return -ENOENT;
+
+        if (pid == 0)
+                r = read_one_line_file("/proc/self/sessionid", &s);
+        else {
+                char *p;
+
+                if (asprintf(&p, "/proc/%lu/sessionid", (unsigned long) pid) < 0)
+                        return -ENOMEM;
+
+                r = read_one_line_file(p, &s);
+                free(p);
+        }
+
+        if (r < 0)
+                return r;
+
+        r = safe_atou32(s, &u);
+        free(s);
+
+        if (r < 0)
+                return r;
+
+        if (u == (uint32_t) -1 || u <= 0)
+                return -ENOENT;
+
+        *id = u;
+        return 0;
+}
+
+int audit_loginuid_from_pid(pid_t pid, uid_t *uid) {
+        char *s;
+        uid_t u;
+        int r;
+
+        assert(uid);
+
+        /* Only use audit login uid if we are executed with sufficient
+         * capabilities so that pam_loginuid could do its job. If we
+         * are lacking the CAP_AUDIT_CONTROL capabality we most likely
+         * are being run in a container and /proc/self/loginuid is
+         * useless since it probably contains a uid of the host
+         * system. */
+
+        if (have_effective_cap(CAP_AUDIT_CONTROL) <= 0)
+                return -ENOENT;
+
+        if (pid == 0)
+                r = read_one_line_file("/proc/self/loginuid", &s);
+        else {
+                char *p;
+
+                if (asprintf(&p, "/proc/%lu/loginuid", (unsigned long) pid) < 0)
+                        return -ENOMEM;
+
+                r = read_one_line_file(p, &s);
+                free(p);
+        }
+
+        if (r < 0)
+                return r;
+
+        r = parse_uid(s, &u);
+        free(s);
+
+        if (r < 0)
+                return r;
+
+        if (u == (uid_t) -1)
+                return -ENOENT;
+
+        *uid = (uid_t) u;
+        return 0;
+}
+
+bool display_is_local(const char *display) {
+        assert(display);
+
+        return
+                display[0] == ':' &&
+                display[1] >= '0' &&
+                display[1] <= '9';
+}
+
+int socket_from_display(const char *display, char **path) {
+        size_t k;
+        char *f, *c;
+
+        assert(display);
+        assert(path);
+
+        if (!display_is_local(display))
+                return -EINVAL;
+
+        k = strspn(display+1, "0123456789");
+
+        f = new(char, sizeof("/tmp/.X11-unix/X") + k);
+        if (!f)
+                return -ENOMEM;
+
+        c = stpcpy(f, "/tmp/.X11-unix/X");
+        memcpy(c, display+1, k);
+        c[k] = 0;
+
+        *path = f;
+
+        return 0;
+}
+
+int get_user_creds(const char **username, uid_t *uid, gid_t *gid, const char **home) {
+        struct passwd *p;
+        uid_t u;
+
+        assert(username);
+        assert(*username);
+
+        /* We enforce some special rules for uid=0: in order to avoid
+         * NSS lookups for root we hardcode its data. */
+
+        if (streq(*username, "root") || streq(*username, "0")) {
+                *username = "root";
+
+                if (uid)
+                        *uid = 0;
+
+                if (gid)
+                        *gid = 0;
+
+                if (home)
+                        *home = "/root";
+                return 0;
+        }
+
+        if (parse_uid(*username, &u) >= 0) {
+                errno = 0;
+                p = getpwuid(u);
+
+                /* If there are multiple users with the same id, make
+                 * sure to leave $USER to the configured value instead
+                 * of the first occurrence in the database. However if
+                 * the uid was configured by a numeric uid, then let's
+                 * pick the real username from /etc/passwd. */
+                if (p)
+                        *username = p->pw_name;
+        } else {
+                errno = 0;
+                p = getpwnam(*username);
+        }
+
+        if (!p)
+                return errno != 0 ? -errno : -ESRCH;
+
+        if (uid)
+                *uid = p->pw_uid;
+
+        if (gid)
+                *gid = p->pw_gid;
+
+        if (home)
+                *home = p->pw_dir;
+
+        return 0;
+}
+
+int get_group_creds(const char **groupname, gid_t *gid) {
+        struct group *g;
+        gid_t id;
+
+        assert(groupname);
+
+        /* We enforce some special rules for gid=0: in order to avoid
+         * NSS lookups for root we hardcode its data. */
+
+        if (streq(*groupname, "root") || streq(*groupname, "0")) {
+                *groupname = "root";
+
+                if (gid)
+                        *gid = 0;
+
+                return 0;
+        }
+
+        if (parse_gid(*groupname, &id) >= 0) {
+                errno = 0;
+                g = getgrgid(id);
+
+                if (g)
+                        *groupname = g->gr_name;
+        } else {
+                errno = 0;
+                g = getgrnam(*groupname);
+        }
+
+        if (!g)
+                return errno != 0 ? -errno : -ESRCH;
+
+        if (gid)
+                *gid = g->gr_gid;
+
+        return 0;
+}
+
+int glob_exists(const char *path) {
+        glob_t g;
+        int r, k;
+
+        assert(path);
+
+        zero(g);
+        errno = 0;
+        k = glob(path, GLOB_NOSORT|GLOB_BRACE, NULL, &g);
+
+        if (k == GLOB_NOMATCH)
+                r = 0;
+        else if (k == GLOB_NOSPACE)
+                r = -ENOMEM;
+        else if (k == 0)
+                r = !strv_isempty(g.gl_pathv);
+        else
+                r = errno ? -errno : -EIO;
+
+        globfree(&g);
+
+        return r;
+}
+
+int dirent_ensure_type(DIR *d, struct dirent *de) {
+        struct stat st;
+
+        assert(d);
+        assert(de);
+
+        if (de->d_type != DT_UNKNOWN)
+                return 0;
+
+        if (fstatat(dirfd(d), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0)
+                return -errno;
+
+        de->d_type =
+                S_ISREG(st.st_mode)  ? DT_REG  :
+                S_ISDIR(st.st_mode)  ? DT_DIR  :
+                S_ISLNK(st.st_mode)  ? DT_LNK  :
+                S_ISFIFO(st.st_mode) ? DT_FIFO :
+                S_ISSOCK(st.st_mode) ? DT_SOCK :
+                S_ISCHR(st.st_mode)  ? DT_CHR  :
+                S_ISBLK(st.st_mode)  ? DT_BLK  :
+                                       DT_UNKNOWN;
+
+        return 0;
+}
+
+int in_search_path(const char *path, char **search) {
+        char **i, *parent;
+        int r;
+
+        r = parent_of_path(path, &parent);
+        if (r < 0)
+                return r;
+
+        r = 0;
+
+        STRV_FOREACH(i, search) {
+                if (path_equal(parent, *i)) {
+                        r = 1;
+                        break;
+                }
+        }
+
+        free(parent);
+
+        return r;
+}
+
+int get_files_in_directory(const char *path, char ***list) {
+        DIR *d;
+        int r = 0;
+        unsigned n = 0;
+        char **l = NULL;
+
+        assert(path);
+
+        /* Returns all files in a directory in *list, and the number
+         * of files as return value. If list is NULL returns only the
+         * number */
+
+        d = opendir(path);
+        if (!d)
+                return -errno;
+
+        for (;;) {
+                struct dirent buffer, *de;
+                int k;
+
+                k = readdir_r(d, &buffer, &de);
+                if (k != 0) {
+                        r = -k;
+                        goto finish;
+                }
+
+                if (!de)
+                        break;
+
+                dirent_ensure_type(d, de);
+
+                if (!dirent_is_file(de))
+                        continue;
+
+                if (list) {
+                        if ((unsigned) r >= n) {
+                                char **t;
+
+                                n = MAX(16, 2*r);
+                                t = realloc(l, sizeof(char*) * n);
+                                if (!t) {
+                                        r = -ENOMEM;
+                                        goto finish;
+                                }
+
+                                l = t;
+                        }
+
+                        assert((unsigned) r < n);
+
+                        l[r] = strdup(de->d_name);
+                        if (!l[r]) {
+                                r = -ENOMEM;
+                                goto finish;
+                        }
+
+                        l[++r] = NULL;
+                } else
+                        r++;
+        }
+
+finish:
+        if (d)
+                closedir(d);
+
+        if (r >= 0) {
+                if (list)
+                        *list = l;
+        } else
+                strv_free(l);
+
+        return r;
+}
+
+char *join(const char *x, ...) {
+        va_list ap;
+        size_t l;
+        char *r, *p;
+
+        va_start(ap, x);
+
+        if (x) {
+                l = strlen(x);
+
+                for (;;) {
+                        const char *t;
+
+                        t = va_arg(ap, const char *);
+                        if (!t)
+                                break;
+
+                        l += strlen(t);
+                }
+        } else
+                l = 0;
+
+        va_end(ap);
+
+        r = new(char, l+1);
+        if (!r)
+                return NULL;
+
+        if (x) {
+                p = stpcpy(r, x);
+
+                va_start(ap, x);
+
+                for (;;) {
+                        const char *t;
+
+                        t = va_arg(ap, const char *);
+                        if (!t)
+                                break;
+
+                        p = stpcpy(p, t);
+                }
+
+                va_end(ap);
+        } else
+                r[0] = 0;
+
+        return r;
+}
+
+bool is_main_thread(void) {
+        static __thread int cached = 0;
+
+        if (_unlikely_(cached == 0))
+                cached = getpid() == gettid() ? 1 : -1;
+
+        return cached > 0;
+}
+
+int block_get_whole_disk(dev_t d, dev_t *ret) {
+        char *p, *s;
+        int r;
+        unsigned n, m;
+
+        assert(ret);
+
+        /* If it has a queue this is good enough for us */
+        if (asprintf(&p, "/sys/dev/block/%u:%u/queue", major(d), minor(d)) < 0)
+                return -ENOMEM;
+
+        r = access(p, F_OK);
+        free(p);
+
+        if (r >= 0) {
+                *ret = d;
+                return 0;
+        }
+
+        /* If it is a partition find the originating device */
+        if (asprintf(&p, "/sys/dev/block/%u:%u/partition", major(d), minor(d)) < 0)
+                return -ENOMEM;
+
+        r = access(p, F_OK);
+        free(p);
+
+        if (r < 0)
+                return -ENOENT;
+
+        /* Get parent dev_t */
+        if (asprintf(&p, "/sys/dev/block/%u:%u/../dev", major(d), minor(d)) < 0)
+                return -ENOMEM;
+
+        r = read_one_line_file(p, &s);
+        free(p);
+
+        if (r < 0)
+                return r;
+
+        r = sscanf(s, "%u:%u", &m, &n);
+        free(s);
+
+        if (r != 2)
+                return -EINVAL;
+
+        /* Only return this if it is really good enough for us. */
+        if (asprintf(&p, "/sys/dev/block/%u:%u/queue", m, n) < 0)
+                return -ENOMEM;
+
+        r = access(p, F_OK);
+        free(p);
+
+        if (r >= 0) {
+                *ret = makedev(m, n);
+                return 0;
+        }
+
+        return -ENOENT;
+}
+
+int file_is_sticky(const char *p) {
+        struct stat st;
+
+        assert(p);
+
+        if (lstat(p, &st) < 0)
+                return -errno;
+
+        return
+                st.st_uid == 0 &&
+                (st.st_mode & S_ISVTX);
+}
+
 static const char *const ioprio_class_table[] = {
         [IOPRIO_CLASS_NONE] = "none",
         [IOPRIO_CLASS_RT] = "realtime",
@@ -5144,7 +5781,7 @@ static const char* const ip_tos_table[] = {
 
 DEFINE_STRING_TABLE_LOOKUP(ip_tos, int);
 
-static const char *const signal_table[] = {
+static const char *const __signal_table[] = {
         [SIGHUP] = "HUP",
         [SIGINT] = "INT",
         [SIGQUIT] = "QUIT",
@@ -5180,4 +5817,122 @@ static const char *const signal_table[] = {
         [SIGSYS] = "SYS"
 };
 
-DEFINE_STRING_TABLE_LOOKUP(signal, int);
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP(__signal, int);
+
+const char *signal_to_string(int signo) {
+        static __thread char buf[12];
+        const char *name;
+
+        name = __signal_to_string(signo);
+        if (name)
+                return name;
+
+        if (signo >= SIGRTMIN && signo <= SIGRTMAX)
+                snprintf(buf, sizeof(buf) - 1, "RTMIN+%d", signo - SIGRTMIN);
+        else
+                snprintf(buf, sizeof(buf) - 1, "%d", signo);
+        char_array_0(buf);
+        return buf;
+}
+
+int signal_from_string(const char *s) {
+        int signo;
+        int offset = 0;
+        unsigned u;
+
+        signo =__signal_from_string(s);
+        if (signo > 0)
+                return signo;
+
+        if (startswith(s, "RTMIN+")) {
+                s += 6;
+                offset = SIGRTMIN;
+        }
+        if (safe_atou(s, &u) >= 0) {
+                signo = (int) u + offset;
+                if (signo > 0 && signo < _NSIG)
+                        return signo;
+        }
+        return -1;
+}
+
+bool kexec_loaded(void) {
+       bool loaded = false;
+       char *s;
+
+       if (read_one_line_file("/sys/kernel/kexec_loaded", &s) >= 0) {
+               if (s[0] == '1')
+                       loaded = true;
+               free(s);
+       }
+       return loaded;
+}
+
+int strdup_or_null(const char *a, char **b) {
+        char *c;
+
+        assert(b);
+
+        if (!a) {
+                *b = NULL;
+                return 0;
+        }
+
+        c = strdup(a);
+        if (!c)
+                return -ENOMEM;
+
+        *b = c;
+        return 0;
+}
+
+int prot_from_flags(int flags) {
+
+        switch (flags & O_ACCMODE) {
+
+        case O_RDONLY:
+                return PROT_READ;
+
+        case O_WRONLY:
+                return PROT_WRITE;
+
+        case O_RDWR:
+                return PROT_READ|PROT_WRITE;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+unsigned long cap_last_cap(void) {
+        static __thread unsigned long saved;
+        static __thread bool valid = false;
+        unsigned long p;
+
+        if (valid)
+                return saved;
+
+        p = (unsigned long) CAP_LAST_CAP;
+
+        if (prctl(PR_CAPBSET_READ, p) < 0) {
+
+                /* Hmm, look downwards, until we find one that
+                 * works */
+                for (p--; p > 0; p --)
+                        if (prctl(PR_CAPBSET_READ, p) >= 0)
+                                break;
+
+        } else {
+
+                /* Hmm, look upwards, until we find one that doesn't
+                 * work */
+                for (;; p++)
+                        if (prctl(PR_CAPBSET_READ, p+1) < 0)
+                                break;
+        }
+
+        saved = p;
+        valid = true;
+
+        return p;
+}