Ticket #156 (closed defect: fixed)
libyaml fails to identify simple keys in very long files on 32-bit platforms
|Reported by:||ppelletier@…||Owned by:||xi|
I have file which contains thousands of relatively short YAML documents, so the file is large (nearly a gigabyte) but the individual documents are not.
I can provide this file if necessary, but I'm not attaching it because it's so large (982M uncompressed, and still 45M when bzip2'ed).
I was getting this error:
Parser error: while parsing a block mapping at line 9259457, column 5 did not find expected key at line 9260367, column 5
This error occurs in both libyaml-0.1.2 and libyaml-0.1.3, but only on 32-bit machines (I tried Ubuntu 8.04 for x86-32, and Intel Mac OS X 10.5 with the compiler in 32-bit mode). If I parse the same file with libyaml on a 64-bit machine (e. g. Ubuntu 8.04 for x86-64), it parses successfully with no error.
I eventually tracked this problem down to an overflow in pointer arithmetic in yaml_parser_save_simple_key(), in yaml-0.1.3/src/scanner.c on line 1125. I changed this:
simple_key.token_number = parser->tokens_parsed + parser->tokens.tail - parser->tokens.head;
simple_key.token_number = parser->tokens_parsed + (parser->tokens.tail - parser->tokens.head);
which caused my file to be parsed successfully, even on 32-bit platforms. So, I would recommend adding this fix to libyaml-0.1.4. Thanks!