chiark / gitweb /
util: make sure all our name_to_handle_at() code makes use of file_handle_union
[elogind.git] / src / shared / path-util.c
index b623fc3dd5adeb9cad7034ee05425b73dd29ab7b..69fcb1660a134531830047795a3edd77d7ef6eb2 100644 (file)
@@ -45,17 +45,6 @@ bool is_path(const char *p) {
         return !!strchr(p, '/');
 }
 
-char *path_get_file_name(const char *p) {
-        char *r;
-
-        assert(p);
-
-        if ((r = strrchr(p, '/')))
-                return r + 1;
-
-        return (char*) p;
-}
-
 int path_get_parent(const char *path, char **_r) {
         const char *e, *a = NULL, *b = NULL, *p;
         char *r;
@@ -101,7 +90,8 @@ char **path_split_and_make_absolute(const char *p) {
         char **l;
         assert(p);
 
-        if (!(l = strv_split(p, ":")))
+        l = strv_split(p, ":");
+        if (!l)
                 return NULL;
 
         if (!path_strv_make_absolute_cwd(l)) {
@@ -125,7 +115,7 @@ char *path_make_absolute(const char *p, const char *prefix) {
 }
 
 char *path_make_absolute_cwd(const char *p) {
-        char *cwd, *r;
+        _cleanup_free_ char *cwd = NULL;
 
         assert(p);
 
@@ -139,10 +129,7 @@ char *path_make_absolute_cwd(const char *p) {
         if (!cwd)
                 return NULL;
 
-        r = path_make_absolute(p, cwd);
-        free(cwd);
-
-        return r;
+        return path_make_absolute(p, cwd);
 }
 
 char **path_strv_make_absolute_cwd(char **l) {
@@ -155,7 +142,8 @@ char **path_strv_make_absolute_cwd(char **l) {
         STRV_FOREACH(s, l) {
                 char *t;
 
-                if (!(t = path_make_absolute_cwd(*s)))
+                t = path_make_absolute_cwd(*s);
+                if (!t)
                         return NULL;
 
                 free(*s);
@@ -165,7 +153,7 @@ char **path_strv_make_absolute_cwd(char **l) {
         return l;
 }
 
-char **path_strv_canonicalize(char **l) {
+char **path_strv_canonicalize_absolute(char **l, const char *prefix) {
         char **s;
         unsigned k = 0;
         bool enomem = false;
@@ -180,13 +168,21 @@ char **path_strv_canonicalize(char **l) {
         STRV_FOREACH(s, l) {
                 char *t, *u;
 
-                t = path_make_absolute_cwd(*s);
-                free(*s);
-                *s = NULL;
-
-                if (!t) {
-                        enomem = true;
+                if (!path_is_absolute(*s))
                         continue;
+
+                if (prefix) {
+                        t = strappend(prefix, *s);
+                        free(*s);
+                        *s = NULL;
+
+                        if (!t) {
+                                enomem = true;
+                                continue;
+                        }
+                } else {
+                        t = *s;
+                        *s = NULL;
                 }
 
                 errno = 0;
@@ -196,7 +192,7 @@ char **path_strv_canonicalize(char **l) {
                                 u = t;
                         else {
                                 free(t);
-                                if (errno == ENOMEM || !errno)
+                                if (errno == ENOMEM || errno == 0)
                                         enomem = true;
 
                                 continue;
@@ -215,11 +211,12 @@ char **path_strv_canonicalize(char **l) {
         return l;
 }
 
-char **path_strv_canonicalize_uniq(char **l) {
+char **path_strv_canonicalize_absolute_uniq(char **l, const char *prefix) {
+
         if (strv_isempty(l))
                 return l;
 
-        if (!path_strv_canonicalize(l))
+        if (!path_strv_canonicalize_absolute(l, prefix))
                 return NULL;
 
         return strv_uniq(l);
@@ -327,11 +324,15 @@ bool path_equal(const char *a, const char *b) {
 }
 
 int path_is_mount_point(const char *t, bool allow_symlink) {
-        char *parent;
-        int r;
-        struct file_handle *h;
+
+        union file_handle_union h = {
+                .handle.handle_bytes = MAX_HANDLE_SZ
+        };
+
         int mount_id, mount_id_parent;
+        char *parent;
         struct stat a, b;
+        int r;
 
         /* We are not actually interested in the file handles, but
          * name_to_handle_at() also passes us the mount ID, hence use
@@ -340,12 +341,9 @@ int path_is_mount_point(const char *t, bool allow_symlink) {
         if (path_equal(t, "/"))
                 return 1;
 
-        h = alloca(MAX_HANDLE_SZ);
-        h->handle_bytes = MAX_HANDLE_SZ;
-
-        r = name_to_handle_at(AT_FDCWD, t, h, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0);
+        r = name_to_handle_at(AT_FDCWD, t, &h.handle, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0);
         if (r < 0) {
-                if (errno == ENOSYS || errno == ENOTSUP)
+                if (IN_SET(errno, ENOSYS, EOPNOTSUPP))
                         /* This kernel or file system does not support
                          * name_to_handle_at(), hence fallback to the
                          * traditional stat() logic */
@@ -361,15 +359,14 @@ int path_is_mount_point(const char *t, bool allow_symlink) {
         if (r < 0)
                 return r;
 
-        h->handle_bytes = MAX_HANDLE_SZ;
-        r = name_to_handle_at(AT_FDCWD, parent, h, &mount_id_parent, 0);
+        h.handle.handle_bytes = MAX_HANDLE_SZ;
+        r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, 0);
         free(parent);
-
         if (r < 0) {
                 /* The parent can't do name_to_handle_at() but the
                  * directory we are interested in can? If so, it must
                  * be a mount point */
-                if (errno == ENOTSUP)
+                if (errno == EOPNOTSUPP)
                         return 1;
 
                 return -errno;
@@ -396,7 +393,6 @@ fallback:
 
         r = lstat(parent, &b);
         free(parent);
-
         if (r < 0)
                 return -errno;
 
@@ -425,3 +421,97 @@ int path_is_os_tree(const char *path) {
 
         return r < 0 ? 0 : 1;
 }
+
+int find_binary(const char *name, char **filename) {
+        assert(name);
+
+        if (strchr(name, '/')) {
+                if (access(name, X_OK) < 0)
+                        return -errno;
+
+                if (filename) {
+                        char *p;
+
+                        p = path_make_absolute_cwd(name);
+                        if (!p)
+                                return -ENOMEM;
+
+                        *filename = p;
+                }
+
+                return 0;
+        } else {
+                const char *path;
+                char *state, *w;
+                size_t l;
+
+                /**
+                 * Plain getenv, not secure_getenv, because we want
+                 * to actually allow the user to pick the binary.
+                 */
+                path = getenv("PATH");
+                if (!path)
+                        path = DEFAULT_PATH;
+
+                FOREACH_WORD_SEPARATOR(w, l, path, ":", state) {
+                        _cleanup_free_ char *p = NULL;
+
+                        if (asprintf(&p, "%.*s/%s", (int) l, w, name) < 0)
+                                return -ENOMEM;
+
+                        if (access(p, X_OK) < 0)
+                                continue;
+
+                        if (filename) {
+                                *filename = path_kill_slashes(p);
+                                p = NULL;
+                        }
+
+                        return 0;
+                }
+
+                return -ENOENT;
+        }
+}
+
+bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
+        bool changed = false;
+        const char* const* i;
+
+        assert(timestamp);
+
+        if (paths == NULL)
+                return false;
+
+        STRV_FOREACH(i, paths) {
+                struct stat stats;
+                usec_t u;
+
+                if (stat(*i, &stats) < 0)
+                        continue;
+
+                u = timespec_load(&stats.st_mtim);
+
+                /* first check */
+                if (*timestamp >= u)
+                        continue;
+
+                log_debug("timestamp of '%s' changed", *i);
+
+                /* update timestamp */
+                if (update) {
+                        *timestamp = u;
+                        changed = true;
+                } else
+                        return true;
+        }
+
+        return changed;
+}
+
+int fsck_exists(const char *fstype) {
+        const char *checker;
+
+        checker = strappenda("fsck.", fstype);
+        return find_binary(checker, NULL);
+}