Before, only the syntax level (parse_*) was able to set the error
string. This patch fixes the situation so that lexical (lex_*) and
stream (stream_*) levels can report detailed error messages.
Also, instead of 0, EOF is now returned by stream on error.
It's no longer needed to load the whole input into a string and then
parse from the string. Instead, the input is read as needed from
a string or file.
Before, json_loads checked for '[' or '{' at the beginning. Now
there's a dedicated function for that: parse_json(). Also rename
parse() to parse_value().
Inside strings, All UTF-8 characters except for \, " and Unicode
control codes are dumped as-is. The control codes that have a special
one-character escape use that escape, and other control codes are
dumped using the \uXXXX escape.
Nothing was appended to strbuffer, so the buffer was left empty. An
empty strbuffer is not an empty string but NULL, so the result was a
segfault.
This patch fixes the problem by initializing strbuffer to an empty
string.
String buffer (strbuffer) is an object that resizes automatically when
data is added to it. It was implemented by generalizing the technique
used in json_dumps().
Petri Lehtinen