AOSP: misc: add callbacks to populate_fs

This patch let the caller of populate_fs registers a set of callbacks that
will be called everytime an inode is created.

Test: mm

Change-Id: I28ae100c4cc81223192860c29366cbac3077fe21
From AOSP commit: 6686ee96494413b48aa3dd70b5db533cbb7e4852

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/misc/create_inode.c b/misc/create_inode.c
index 8ce3faf..8f7445d 100644 (file)
--- a/misc/create_inode.c
+++ b/misc/create_inode.c
@@ -683,10 +683,31 @@ out:
        return retval;
 }
 
+struct file_info {
+       char *path;
+       size_t path_len;
+       size_t path_max_len;
+};
+
+static errcode_t path_append(struct file_info *target, const char *file)
+{
+       if (strlen(file) + target->path_len + 1 > target->path_max_len) {
+               target->path_max_len *= 2;
+               target->path = realloc(target->path, target->path_max_len);
+               if (!target->path)
+                       return EXT2_ET_NO_MEMORY;
+       }
+       target->path_len += sprintf(target->path + target->path_len, "/%s",
+                                   file);
+       return 0;
+}
+
 /* Copy files from source_dir to fs */
 static errcode_t __populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
                               const char *source_dir, ext2_ino_t root,
-                              struct hdlinks_s *hdlinks)
+                              struct hdlinks_s *hdlinks,
+                              struct file_info *target,
+                              struct fs_ops_callbacks *fs_callbacks)
 {
        const char      *name;
        DIR             *dh;
@@ -698,6 +719,7 @@ static errcode_t __populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
        errcode_t       retval = 0;
        int             read_cnt;
        int             hdlink;
+       size_t          cur_dir_path_len;
 
        if (chdir(source_dir) < 0) {
                retval = errno;
@@ -745,6 +767,19 @@ static errcode_t __populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
                                save_inode = 1;
                }
 
+               cur_dir_path_len = target->path_len;
+               retval = path_append(target, name);
+               if (retval)
+                       return retval;
+
+               if (fs_callbacks && fs_callbacks->create_new_inode) {
+                       retval = fs_callbacks->create_new_inode(fs,
+                               target->path, name, parent_ino, root,
+                               st.st_mode & S_IFMT);
+                       if (retval)
+                               goto out;
+               }
+
                switch(st.st_mode & S_IFMT) {
                case S_IFCHR:
                case S_IFBLK:
@@ -822,7 +857,8 @@ find_lnf:
                                        goto out;
                        }
                        /* Populate the dir recursively*/
-                       retval = __populate_fs(fs, ino, name, root, hdlinks);
+                       retval = __populate_fs(fs, ino, name, root, hdlinks,
+                                              target, fs_callbacks);
                        if (retval)
                                goto out;
                        if (chdir("..")) {
@@ -858,6 +894,14 @@ find_lnf:
                        goto out;
                }
 
+               if (fs_callbacks && fs_callbacks->end_create_new_inode) {
+                       retval = fs_callbacks->end_create_new_inode(fs,
+                               target->path, name, parent_ino, root,
+                               st.st_mode & S_IFMT);
+                       if (retval)
+                               goto out;
+               }
+
                /* Save the hardlink ino */
                if (save_inode) {
                        /*
@@ -883,6 +927,8 @@ find_lnf:
                        hdlinks->hdl[hdlinks->count].dst_ino = ino;
                        hdlinks->count++;
                }
+               target->path_len = cur_dir_path_len;
+               target->path[target->path_len] = 0;
        }
 
 out:
@@ -890,9 +936,11 @@ out:
        return retval;
 }
 
-errcode_t populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
-                     const char *source_dir, ext2_ino_t root)
+errcode_t populate_fs2(ext2_filsys fs, ext2_ino_t parent_ino,
+                      const char *source_dir, ext2_ino_t root,
+                      struct fs_ops_callbacks *fs_callbacks)
 {
+       struct file_info file_info;
        struct hdlinks_s hdlinks;
        errcode_t retval;
 
@@ -910,8 +958,20 @@ errcode_t populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
                return retval;
        }
 
-       retval = __populate_fs(fs, parent_ino, source_dir, root, &hdlinks);
+       file_info.path_len = 0;
+       file_info.path_max_len = 255;
+       file_info.path = calloc(file_info.path_max_len, 1);
 
+       retval = __populate_fs(fs, parent_ino, source_dir, root, &hdlinks,
+                              &file_info, fs_callbacks);
+
+       free(file_info.path);
        free(hdlinks.hdl);
        return retval;
 }
+
+errcode_t populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
+                     const char *source_dir, ext2_ino_t root)
+{
+       return populate_fs2(fs, parent_ino, source_dir, root, NULL);
+}

diff --git a/misc/create_inode.h b/misc/create_inode.h
index cf49df2..17309c6 100644 (file)
--- a/misc/create_inode.h
+++ b/misc/create_inode.h
@@ -24,9 +24,21 @@ struct hdlinks_s
 
 #define HDLINK_CNT     (4)
 
+struct fs_ops_callbacks {
+       errcode_t (* create_new_inode)(ext2_filsys fs, const char *target_path,
+               const char *name, ext2_ino_t parent_ino, ext2_ino_t root,
+               mode_t mode);
+       errcode_t (* end_create_new_inode)(ext2_filsys fs,
+               const char *target_path, const char *name,
+               ext2_ino_t parent_ino, ext2_ino_t root, mode_t mode);
+};
+
 /* For populating the filesystem */
 extern errcode_t populate_fs(ext2_filsys fs, ext2_ino_t parent_ino,
                             const char *source_dir, ext2_ino_t root);
+extern errcode_t populate_fs2(ext2_filsys fs, ext2_ino_t parent_ino,
+                             const char *source_dir, ext2_ino_t root,
+                             struct fs_ops_callbacks *fs_callbacks);
 extern errcode_t do_mknod_internal(ext2_filsys fs, ext2_ino_t cwd,
                                   const char *name, struct stat *st);
 extern errcode_t do_symlink_internal(ext2_filsys fs, ext2_ino_t cwd,