+static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_picture_cstring_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__byte **data, FLAC__uint32 *length, FLAC__uint32 length_len)
+{
+ FLAC__byte buffer[sizeof(FLAC__uint32)];
+
+ FLAC__ASSERT(0 != data);
+ FLAC__ASSERT(length_len%8 == 0);
+
+ length_len /= 8; /* convert to bytes */
+
+ FLAC__ASSERT(sizeof(buffer) >= length_len);
+
+ if(read_cb(buffer, 1, length_len, handle) != length_len)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ *length = unpack_uint32_(buffer, length_len);
+
+ if(0 != *data)
+ free(*data);
+
+ if(0 == (*data = (FLAC__byte*)safe_malloc_add_2op_(*length, /*+*/1)))
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
+
+ if(*length > 0) {
+ if(read_cb(*data, 1, *length, handle) != *length)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ }
+
+ (*data)[*length] = '\0';
+
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
+}
+
+FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_picture_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_Picture *block)
+{
+ FLAC__Metadata_SimpleIteratorStatus status;
+ FLAC__byte buffer[4]; /* asserted below that this is big enough */
+ FLAC__uint32 len;
+
+ FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_PICTURE_TYPE_LEN/8);
+ FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN/8);
+ FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN/8);
+ FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN/8);
+ FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_PICTURE_COLORS_LEN/8);
+
+ FLAC__ASSERT(FLAC__STREAM_METADATA_PICTURE_TYPE_LEN % 8 == 0);
+ len = FLAC__STREAM_METADATA_PICTURE_TYPE_LEN / 8;
+ if(read_cb(buffer, 1, len, handle) != len)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ block->type = (FLAC__StreamMetadata_Picture_Type)unpack_uint32_(buffer, len);
+
+ if((status = read_metadata_block_data_picture_cstring_cb_(handle, read_cb, (FLAC__byte**)(&(block->mime_type)), &len, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN)) != FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK)
+ return status;
+
+ if((status = read_metadata_block_data_picture_cstring_cb_(handle, read_cb, &(block->description), &len, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN)) != FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK)
+ return status;
+
+ FLAC__ASSERT(FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN % 8 == 0);
+ len = FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN / 8;
+ if(read_cb(buffer, 1, len, handle) != len)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ block->width = unpack_uint32_(buffer, len);
+
+ FLAC__ASSERT(FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN % 8 == 0);
+ len = FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN / 8;
+ if(read_cb(buffer, 1, len, handle) != len)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ block->height = unpack_uint32_(buffer, len);
+
+ FLAC__ASSERT(FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN % 8 == 0);
+ len = FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN / 8;
+ if(read_cb(buffer, 1, len, handle) != len)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ block->depth = unpack_uint32_(buffer, len);
+
+ FLAC__ASSERT(FLAC__STREAM_METADATA_PICTURE_COLORS_LEN % 8 == 0);
+ len = FLAC__STREAM_METADATA_PICTURE_COLORS_LEN / 8;
+ if(read_cb(buffer, 1, len, handle) != len)
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
+ block->colors = unpack_uint32_(buffer, len);
+
+ /* for convenience we use read_metadata_block_data_picture_cstring_cb_() even though it adds an extra terminating NUL we don't use */
+ if((status = read_metadata_block_data_picture_cstring_cb_(handle, read_cb, &(block->data), &(block->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN)) != FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK)
+ return status;
+
+ return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
+}
+