1 files changed, 166 insertions, 0 deletions
diff --git a/src/basic/mkdir.c b/src/basic/mkdir.c
new file mode 100644
index 0000000..4bb65d5
--- /dev/null
+++ b/src/basic/mkdir.c
@@ -0,0 +1,166 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <errno.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "alloc-util.h"
+#include "fs-util.h"
+#include "macro.h"
+#include "mkdir.h"
+#include "path-util.h"
+#include "stat-util.h"
+#include "stdio-util.h"
+#include "user-util.h"
+
+int mkdir_safe_internal(const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags, mkdir_func_t _mkdir) {
+        struct stat st;
+        int r;
+
+        assert(_mkdir != mkdir);
+
+        if (_mkdir(path, mode) >= 0) {
+                r = chmod_and_chown(path, mode, uid, gid);
+                if (r < 0)
+                        return r;
+        }
+
+        if (lstat(path, &st) < 0)
+                return -errno;
+
+        if ((flags & MKDIR_FOLLOW_SYMLINK) && S_ISLNK(st.st_mode)) {
+                _cleanup_free_ char *p = NULL;
+
+                r = chase_symlinks(path, NULL, CHASE_NONEXISTENT, &p);
+                if (r < 0)
+                        return r;
+                if (r == 0)
+                        return mkdir_safe_internal(p, mode, uid, gid,
+                                                   flags & ~MKDIR_FOLLOW_SYMLINK,
+                                                   _mkdir);
+
+                if (lstat(p, &st) < 0)
+                        return -errno;
+        }
+
+        if (!S_ISDIR(st.st_mode)) {
+                log_full(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG,
+                         "Path \"%s\" already exists and is not a directory, refusing.", path);
+                return -ENOTDIR;
+        }
+        if ((st.st_mode & 0007) > (mode & 0007) ||
+            (st.st_mode & 0070) > (mode & 0070) ||
+            (st.st_mode & 0700) > (mode & 0700)) {
+                log_full(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG,
+                         "Directory \"%s\" already exists, but has mode %04o that is too permissive (%04o was requested), refusing.",
+                         path, st.st_mode & 0777, mode);
+                return -EEXIST;
+        }
+        if ((uid != UID_INVALID && st.st_uid != uid) ||
+            (gid != GID_INVALID && st.st_gid != gid)) {
+                char u[DECIMAL_STR_MAX(uid_t)] = "-", g[DECIMAL_STR_MAX(gid_t)] = "-";
+
+                if (uid != UID_INVALID)
+                        xsprintf(u, UID_FMT, uid);
+                if (gid != UID_INVALID)
+                        xsprintf(g, GID_FMT, gid);
+                log_full(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG,
+                         "Directory \"%s\" already exists, but is owned by "UID_FMT":"GID_FMT" (%s:%s was requested), refusing.",
+                         path, st.st_uid, st.st_gid, u, g);
+                return -EEXIST;
+        }
+
+        return 0;
+}
+
+int mkdir_errno_wrapper(const char *pathname, mode_t mode) {
+        if (mkdir(pathname, mode) < 0)
+                return -errno;
+        return 0;
+}
+
+int mkdirat_errno_wrapper(int dirfd, const char *pathname, mode_t mode) {
+        if (mkdirat(dirfd, pathname, mode) < 0)
+                return -errno;
+        return 0;
+}
+
+int mkdir_safe(const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags) {
+        return mkdir_safe_internal(path, mode, uid, gid, flags, mkdir_errno_wrapper);
+}
+
+int mkdir_parents_internal(const char *prefix, const char *path, mode_t mode, mkdir_func_t _mkdir) {
+        const char *p, *e;
+        int r;
+
+        assert(path);
+        assert(_mkdir != mkdir);
+
+        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;
+
+        p = strndupa(path, e - path);
+        r = is_dir(p, true);
+        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 = _mkdir(t, mode);
+                if (r < 0 && r != -EEXIST)
+                        return r;
+        }
+}
+
+int mkdir_parents(const char *path, mode_t mode) {
+        return mkdir_parents_internal(NULL, path, mode, mkdir_errno_wrapper);
+}
+
+int mkdir_p_internal(const char *prefix, const char *path, mode_t mode, mkdir_func_t _mkdir) {
+        int r;
+
+        /* Like mkdir -p */
+
+        assert(_mkdir != mkdir);
+
+        r = mkdir_parents_internal(prefix, path, mode, _mkdir);
+        if (r < 0)
+                return r;
+
+        r = _mkdir(path, mode);
+        if (r < 0 && (r != -EEXIST || is_dir(path, true) <= 0))
+                return r;
+
+        return 0;
+}
+
+int mkdir_p(const char *path, mode_t mode) {
+        return mkdir_p_internal(NULL, path, mode, mkdir_errno_wrapper);
+}