libfstools: fix foreachdir() to pass dir with a trailing slash

[project/fstools.git] / libfstools / overlay.c

diff --git a/libfstools/overlay.c b/libfstools/overlay.c
index f68065e4fb7e598f0c9e49296add7966be39be2e..d7dd74b1c06aaa134f970b9a0f6862e0a11ce14a 100644 (file)
--- a/libfstools/overlay.c
+++ b/libfstools/overlay.c
@@ -67,25 +67,49 @@ handle_rmdir(const char *dir)
 void
 foreachdir(const char *dir, int (*cb)(const char*))
 {
+       static char *globdir = NULL;
+       static size_t globdirlen = 0;
        struct stat s = { 0 };
-       char globdir[256];
+       size_t dirlen = strlen(dir);
        glob_t gl;
        int j;
 
-       if (dir[strlen(dir) - 1] == '/')
-               snprintf(globdir, 256, "%s*", dir);
+       if (dirlen + sizeof("/*") > globdirlen) {
+               /* Alloc extra 256 B to avoid too many reallocs */
+               size_t len = dirlen + sizeof("/*") + 256;
+               char *tmp;
+
+               tmp = realloc(globdir, len);
+               if (!tmp)
+                       return;
+               globdir = tmp;
+               globdirlen = len;
+       }
+
+       if (dir[dirlen - 1] == '/')
+               sprintf(globdir, "%s*", dir);
        else
-               snprintf(globdir, 256, "%s/*", dir); /**/
+               sprintf(globdir, "%s/*", dir);
 
+       /* Include GLOB_MARK as callbacks expect a trailing slash */
        if (!glob(globdir, GLOB_NOESCAPE | GLOB_MARK | GLOB_ONLYDIR, NULL, &gl))
                for (j = 0; j < gl.gl_pathc; j++) {
                        char *dir = gl.gl_pathv[j];
                        int len = strlen(gl.gl_pathv[j]);
+                       int err;
 
-                       if (len > 1 && dir[len - 1] == '/')
+                       /* Quick way of skipping files */
+                       if (dir[len - 1] != '/')
+                               continue;
+
+                       /* lstat needs path without a trailing slash */
+                       if (len > 1)
                                dir[len - 1] = '\0';
+                       err = lstat(gl.gl_pathv[j], &s);
+                       if (len > 1)
+                               dir[len - 1] = '/';
 
-                       if (!lstat(gl.gl_pathv[j], &s) && !S_ISLNK(s.st_mode))
+                       if (!err && !S_ISLNK(s.st_mode))
                                foreachdir(gl.gl_pathv[j], cb);
        }
        cb(dir);
@@ -192,18 +216,33 @@ handle_whiteout(const char *dir)
        return 0;
 }
 
+static char *overlay_fs_name(int type)
+{
+       switch (type) {
+               case FS_EXT4:
+                       return "ext4";
+               case FS_F2FS:
+                       return "f2fs";
+               case FS_UBIFS:
+                       return "ubifs";
+               case FS_JFFS2:
+               default:
+                       return "jffs2";
+       }
+}
+
 int
 jffs2_switch(struct volume *v)
 {
-       char *mp;
-       int ret = -1;
+       char *mp, *fs_name;
+       int type;
 
        if (find_overlay_mount("overlayfs:/tmp/root"))
                return -1;
 
        if (find_filesystem("overlay")) {
                ULOG_ERR("overlayfs not supported by kernel\n");
-               return ret;
+               return -1;
        }
 
        volume_init(v);
@@ -213,44 +252,35 @@ jffs2_switch(struct volume *v)
                return -1;
        }
 
-       switch (volume_identify(v)) {
+       type = volume_identify(v);
+       fs_name = overlay_fs_name(type);
+
+       switch (type) {
        case FS_NONE:
                ULOG_ERR("no jffs2 marker found\n");
                /* fall through */
 
        case FS_DEADCODE:
-               ret = switch2jffs(v);
-               if (!ret) {
-                       ULOG_INFO("performing overlay whiteout\n");
-                       umount2("/tmp/root", MNT_DETACH);
-                       foreachdir("/overlay/", handle_whiteout);
-               }
-               break;
+               if (switch2jffs(v))
+                       return -1;
 
-       case FS_JFFS2:
-               ret = overlay_mount(v, "jffs2");
-               if (ret)
-                       break;
-               if (mount_move("/tmp", "", "/overlay") || fopivot("/overlay", "/rom")) {
-                       ULOG_ERR("switching to jffs2 failed\n");
-                       ret = -1;
-               }
+               ULOG_INFO("performing overlay whiteout\n");
+               umount2("/tmp/root", MNT_DETACH);
+               foreachdir("/overlay/", handle_whiteout);
                break;
 
+       case FS_EXT4:
+       case FS_F2FS:
        case FS_UBIFS:
-               ret = overlay_mount(v, "ubifs");
-               if (ret)
-                       break;
+               if (overlay_mount(v, fs_name))
+                       return -1;
                if (mount_move("/tmp", "", "/overlay") || fopivot("/overlay", "/rom")) {
-                       ULOG_ERR("switching to ubifs failed\n");
-                       ret = -1;
+                       ULOG_ERR("switching to %s failed\n", fs_name);
+                       return -1;
                }
                break;
        }
 
-       if (ret)
-               return ret;
-
        sync();
        fs_state_set("/overlay", FS_STATE_READY);
        return 0;
@@ -258,21 +288,13 @@ jffs2_switch(struct volume *v)
 
 static int overlay_mount_fs(struct volume *v)
 {
-       char *fstype;
+       char *fstype = overlay_fs_name(volume_identify(v));
 
        if (mkdir("/tmp/overlay", 0755)) {
                ULOG_ERR("failed to mkdir /tmp/overlay: %s\n", strerror(errno));
                return -1;
        }
 
-       fstype = "jffs2";
-
-       switch (volume_identify(v)) {
-       case FS_UBIFS:
-               fstype = "ubifs";
-               break;
-       }
-
        if (mount(v->blk, "/tmp/overlay", fstype, MS_NOATIME, NULL)) {
                ULOG_ERR("failed to mount -t %s %s /tmp/overlay: %s\n",
                         fstype, v->blk, strerror(errno));
@@ -324,7 +346,7 @@ int fs_state_set(const char *dir, enum fs_state state)
 
 int mount_overlay(struct volume *v)
 {
-       char *mp;
+       char *mp, *fs_name;
 
        if (!v)
                return -1;
@@ -358,9 +380,10 @@ int mount_overlay(struct volume *v)
                break;
        }
 
-       ULOG_INFO("switching to jffs2 overlay\n");
+       fs_name = overlay_fs_name(volume_identify(v));
+       ULOG_INFO("switching to %s overlay\n", fs_name);
        if (mount_move("/tmp", "", "/overlay") || fopivot("/overlay", "/rom")) {
-               ULOG_ERR("switching to jffs2 failed - fallback to ramoverlay\n");
+               ULOG_ERR("switching to %s failed - fallback to ramoverlay\n", fs_name);
                return ramoverlay();
        }