capability: use /proc/sys/kernel/cap_last_cap

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index e95f6ed24781a6313b6ee136cb446590a8ecf379..dfaf7f7f45b07416bcd365b869c7b05b4618d752 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -59,6 +59,7 @@
 #include <langinfo.h>
 #include <locale.h>
 #include <sys/personality.h>
+#include <sys/xattr.h>
 #include <libgen.h>
 #undef basename
 
@@ -84,6 +85,7 @@
 #include "gunicode.h"
 #include "virt.h"
 #include "def.h"
+#include "sparse-endian.h"
 
 int saved_argc = 0;
 char **saved_argv = NULL;
@@ -1150,7 +1152,7 @@ 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);
@@ -1163,17 +1165,17 @@ 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) {
@@ -5182,6 +5184,9 @@ 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) {
@@ -7558,3 +7563,93 @@ int openpt_in_namespace(pid_t pid, int flags) {
 
         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);
+
+        le = htole64((uint64_t) usec);
+        if (fsetxattr(fd, "user.crtime_usec", &le, sizeof(le), 0) < 0)
+                return -errno;
+
+        return 0;
+}