Function ifwi_parse

util/cbfstool/ifwitool.c:860–917

Parse input image file to identify different sub-partitions. */

/* Parse input image file to identify different sub-partitions. */
static int ifwi_parse(void)
{
	DEBUG("Parsing IFWI image...\n");
	const char *image_name = param.image_name;

	/* Read input file. */
	struct buffer *buff = &ifwi_image.input_buff;
	if (buffer_from_file(buff, image_name)) {
		ERROR("Failed to read input file %s.\n", image_name);
		return -1;
	}

	INFO("Buffer %p size 0x%zx\n", buff->data, buff->size);

	/* Look for BPDT signature at 4K intervals. */
	size_t offset = 0, lbp = LBP1;
	void *data = buffer_get(buff);

	while (offset < buffer_size(buff)) {
		if (read_at_le32(data, offset) == BPDT_SIGNATURE) {
			if (lbp == param.logical_boot_partition)
				break;
			offset += bpdt_size((uint8_t *)data + offset);
			lbp++;
		} else
			offset += 4 * KiB;
	}

	if (offset >= buffer_size(buff)) {
		ERROR("Image does not contain BPDT for LBP=%zd!!\n",
		      param.logical_boot_partition);
		return -1;
	}

	ifwi_image.input_ifwi_start_offset = offset;
	INFO("BPDT starts at offset 0x%zx.\n", offset);

	data = (uint8_t *)data + offset;
	size_t ifwi_size = buffer_size(buff) - offset;

	/* Read BPDT and sub-partitions. */
	uintptr_t end_offset;
	end_offset = ifwi_image.input_ifwi_start_offset +
		alloc_bpdt_buffer(data, ifwi_size, 0, &ifwi_image.bpdt, "BPDT");

	/* Parse S-BPDT, if any. */
	parse_sbpdt(data, ifwi_size);

	/*
	 * Store end offset of IFWI. Required for copying any trailing non-IFWI
	 * part of the image.
	 * ASSUMPTION: IFWI image always ends on a 4K boundary.
	 */
	ifwi_image.input_ifwi_end_offset = ALIGN_UP(end_offset, 4 * KiB);
	DEBUG("Parsing done.\n");

	return 0;
}