sdat2img.py

#!/usr/bin/env python
#encoding:utf8
#====================================================
#          FILE: sdat2img.py
#       AUTHORS: xpirt - luxi78 - howellzhu
#          DATE: 2014-12-24 13:18:27 CST
#====================================================
import sys, os

try:
    TRANSFER_LIST_FILE = str(sys.argv[1])
    NEW_DATA_FILE = str(sys.argv[2])
    OUTPUT_IMAGE_FILE = str(sys.argv[3])
except IndexError:  
   print ("\nsdat2img - usage is: \n\n      sdat2img <transfer_list> <system_new_file> <system_img>\n\n")
   print ("Visit xda thread for more information.\n")
   os.system("pause")
   sys.exit()

BLOCK_SIZE = 4096

def rangeset(src):
    src_set = src.split(',')
    num_set =  [int(item) for item in src_set]
    if len(num_set) != num_set[0]+1:
        print ('Error on parsing following data to rangeset:\n%s' % src)
        sys.exit(1)

    return tuple ([ (num_set[i], num_set[i+1]) for i in range(1, len(num_set), 2) ])

def parse_transfer_list_file(path):
    trans_list = open(TRANSFER_LIST_FILE, 'r')
    version = int(trans_list.readline())
    new_blocks = int(trans_list.readline())
    
    for line in trans_list:
        line = line.split(' ')
        cmd = line[0]
        if 'erase' == cmd:
            erase_block_set = rangeset(line[1])
        elif 'new' == cmd:
            new_block_set = rangeset(line[1])
        else:
            print ('Error command %s' % cmd)
            trans_list.close()
            sys.exit(1)

    trans_list.close()
    return version, new_blocks, erase_block_set, new_block_set 

def init_output_file_size(output_file_obj, erase_block_set):
    max_block_num = max(pair[1] for pair in erase_block_set)
    output_file_obj.seek(max_block_num*BLOCK_SIZE - 1)
    output_file_obj.write('\0'.encode('utf-8'))
    output_file_obj.flush()

def main(argv):
    version, new_blocks, erase_block_set, new_block_set =  parse_transfer_list_file(TRANSFER_LIST_FILE)
    output_img = open( OUTPUT_IMAGE_FILE, 'wb')
    init_output_file_size(output_img, erase_block_set)
    new_data_file = open(NEW_DATA_FILE, 'rb')

    for block in new_block_set:
        begin = block[0]
        end = block[1]
        block_count = end - begin
        print ("Reading %d blocks..." % block_count),
        data = new_data_file.read(block_count*BLOCK_SIZE)
        print ("Writing to %d..." % begin),
        output_img.seek(begin*BLOCK_SIZE)
        output_img.write(data)
        print ("Done!")

    output_img.close()
    new_data_file.close()

if __name__ == "__main__":
    main(sys.argv)