-static void read_base64(FILE *src_stream, FILE *dst_stream)
-{
- int term_count = 0;
-
- while (1) {
- unsigned char translated[4];
- int count = 0;
-
- /* Process one group of 4 chars */
- while (count < 4) {
- char *table_ptr;
- int ch;
-
- /* Get next _valid_ character.
- * bb_uuenc_tbl_base64[] contains this string:
- * 0 1 2 3 4 5 6
- * 012345678901234567890123456789012345678901234567890123456789012345
- * "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n"
- */
- do {
- ch = fgetc(src_stream);
- if (ch == EOF) {
- if (ENABLE_BASE64
- && (!ENABLE_UUDECODE || applet_name[0] == 'b')
- && count == 0
- ) {
- return;
- }
- bb_error_msg_and_die("short file");
- }
- table_ptr = strchr(bb_uuenc_tbl_base64, ch);
- } while (!table_ptr);
-
- /* Convert encoded character to decimal */
- ch = table_ptr - bb_uuenc_tbl_base64;
-
- if (ch == 65 /* '\n' */) {
- /* Terminating "====" line? */
- if (term_count == 4)
- return; /* yes */
- term_count = 0;
- continue;
- }
- /* ch is 64 is char was '=', otherwise 0..63 */
- translated[count] = ch & 63; /* 64 -> 0 */
- if (ch == 64) {
- term_count++;
- break;
- }
- count++;
- }
-
- /* Merge 6 bit chars to 8 bit.
- * count can be < 4 when we decode the tail:
- * "eQ==" -> "y", not "y NUL NUL"
- */
- if (count > 1)
- fputc(translated[0] << 2 | translated[1] >> 4, dst_stream);
- if (count > 2)
- fputc(translated[1] << 4 | translated[2] >> 2, dst_stream);
- if (count > 3)
- fputc(translated[2] << 6 | translated[3], dst_stream);
- } /* while (1) */
-}
-