[PATCH 5/7] android_bootimg: Implement read

[Shea Levy]

---
 grub-core/fs/android_bootimg.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/grub-core/fs/android_bootimg.c b/grub-core/fs/android_bootimg.c
index 793e0aa..13d77fd 100644
--- a/grub-core/fs/android_bootimg.c
+++ b/grub-core/fs/android_bootimg.c
@@ -67,11 +67,11 @@ typedef enum
 bootimg_file_t;
 
 static bootimg_file_t
-grub_android_bootimg_handle_path (const char * path)
+grub_android_bootimg_handle_path (const char *path)
 {
   if (!path || path[0] != '/')
     return BAD_NAME;
-  const char * path_iter;
+  const char *path_iter;
   for (path_iter = path + 1; *path_iter; ++path_iter) {
     if (*path_iter == '/')
       continue;
@@ -97,7 +97,7 @@ grub_android_bootimg_handle_path (const char * path)
 }
 
 static grub_err_t
-grub_android_bootimg_hdr (grub_disk_t disk, struct boot_img_hdr * hd)
+grub_android_bootimg_hdr (grub_disk_t disk, struct boot_img_hdr *hd)
 {
   if (grub_disk_read (disk, 0, 0, sizeof *hd, hd))
     goto fail;
@@ -116,7 +116,7 @@ fail:
 }
 
 static grub_err_t
-grub_android_bootimg_dir (grub_device_t device, const char * path,
+grub_android_bootimg_dir (grub_device_t device, const char *path,
                grub_fs_dir_hook_t hook, void *hook_data)
 {
   struct boot_img_hdr hd;
@@ -175,7 +175,7 @@ grub_android_bootimg_open (grub_file_t file, const char 
*name)
   if (grub_android_bootimg_hdr (file->device->disk, &hd))
     return grub_errno;
 
-  grub_off_t * begin_offset;
+  grub_off_t *begin_offset;
 
   bootimg_file_t fn = grub_android_bootimg_handle_path (name);
   switch (fn)
@@ -209,8 +209,19 @@ grub_android_bootimg_open (grub_file_t file, const char 
*name)
 static grub_ssize_t
 grub_android_bootimg_read (grub_file_t file, char *buf, grub_size_t len)
 {
-  grub_errno = GRUB_ERR_NOT_IMPLEMENTED_YET;
-  return -1;
+  grub_size_t len_left = file->size - file->offset;
+  len = len > len_left ? len_left : len;
+  grub_off_t *begin_offset = file->data;
+  grub_off_t actual_offset = *begin_offset + file->offset;
+  file->device->disk->read_hook = file->read_hook;
+  file->device->disk->read_hook_data = file->read_hook_data;
+  grub_errno = grub_disk_read (file->device->disk, 0, actual_offset, len, buf);
+  file->device->disk->read_hook = 0;
+
+  if (grub_errno)
+    return -1;
+  else
+    return len;
 }
 
 static grub_err_t
-- 
2.7.0