src/shared: refactor shared code

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>

1 files changed, 157 insertions, 0 deletions

diff --git a/src/shared/mkdir.c b/src/shared/mkdir.c
new file mode 100644
index 0000000000..770ee994c4
--- /dev/null
+++ b/src/shared/mkdir.c
@@ -0,0 +1,157 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <limits.h>
+
+#include "label.h"
+#include "util.h"
+#include "mkdir.h"
+
+static int is_dir(const char* path) {
+        struct stat st;
+
+        if (stat(path, &st) < 0)
+                return -errno;
+
+        return S_ISDIR(st.st_mode);
+}
+
+
+char* path_startswith(const char *path, const char *prefix) {
+        assert(path);
+        assert(prefix);
+
+        if ((path[0] == '/') != (prefix[0] == '/'))
+                return NULL;
+
+        for (;;) {
+                size_t a, b;
+
+                path += strspn(path, "/");
+                prefix += strspn(prefix, "/");
+
+                if (*prefix == 0)
+                        return (char*) path;
+
+                if (*path == 0)
+                        return NULL;
+
+                a = strcspn(path, "/");
+                b = strcspn(prefix, "/");
+
+                if (a != b)
+                        return NULL;
+
+                if (memcmp(path, prefix, a) != 0)
+                        return NULL;
+
+                path += a;
+                prefix += b;
+        }
+}
+
+static int mkdir_parents_internal(const char *prefix, const char *path, mode_t mode, bool apply) {
+        const char *p, *e;
+        int r;
+
+        assert(path);
+
+        if (prefix && !path_startswith(path, prefix))
+                return -ENOTDIR;
+
+        /* return immediately if directory exists */
+        e = strrchr(path, '/');
+        if (!e)
+                return -EINVAL;
+
+        if (e == path)
+                return 0;
+
+	char buf[PATH_MAX + 1];
+	p = buf;
+	assert(e-path < sizeof(buf));
+	memcpy(buf, path, e-path);
+	buf[e-path] = 0;
+
+        r = is_dir(p);
+        if (r > 0)
+                return 0;
+        if (r == 0)
+                return -ENOTDIR;
+
+        /* create every parent directory in the path, except the last component */
+        p = path + strspn(path, "/");
+        for (;;) {
+                char t[strlen(path) + 1];
+
+                e = p + strcspn(p, "/");
+                p = e + strspn(e, "/");
+
+                /* Is this the last component? If so, then we're
+                 * done */
+                if (*p == 0)
+                        return 0;
+
+                memcpy(t, path, e - path);
+                t[e-path] = 0;
+
+                if (prefix && path_startswith(prefix, t))
+                        continue;
+
+                r = label_mkdir(t, mode, apply);
+                if (r < 0 && errno != EEXIST)
+                        return -errno;
+        }
+}
+
+int mkdir_parents(const char *path, mode_t mode) {
+        return mkdir_parents_internal(NULL, path, mode, false);
+}
+
+int mkdir_parents_label(const char *path, mode_t mode) {
+        return mkdir_parents_internal(NULL, path, mode, true);
+}
+
+static int mkdir_p_internal(const char *prefix, const char *path, mode_t mode, bool apply) {
+        int r;
+
+        /* Like mkdir -p */
+
+        r = mkdir_parents_internal(prefix, path, mode, apply);
+        if (r < 0)
+                return r;
+
+        r = label_mkdir(path, mode, apply);
+        if (r < 0 && (errno != EEXIST || is_dir(path) <= 0))
+                return -errno;
+
+        return 0;
+}
+
+int mkdir_p(const char *path, mode_t mode) {
+        return mkdir_p_internal(NULL, path, mode, false);
+}