This is a parser written in C for multipart bodies. The code was mostly
inspired by joyent/http-parser. The
parser does not make any syscalls nor allocations, it does not buffer data
except the boundary that you pass to mulpartparser_init() function.
One multipartparser struct must be initialized every time you need to parse
a body. The multipartparser_callbacks struct can be initialized only once
and can be used by many parsers at the same time. The code to initialize a
multipart parser should be similar to this:
multipartparser_callbacks callbacks;
multipartparser parser;
multipartparser_callbacks_init(&callbacks); // It only sets all callbacks to NULL.
callbacks.on_body_begin = &on_body_begin;
callbacks.on_part_begin = &on_part_begin;
callbacks.on_header_field = &on_header_field;
callbacks.on_header_value = &on_header_value;
callbacks.on_headers_complete = &on_headers_complete;
callbacks.on_data = &on_data;
callbacks.on_part_end = &on_part_end;
callbacks.on_body_end = &on_body_end;
multipartparser_init(&parser, boundary);
parser->data = my_data;When there is data to parse call the multipart parser like this:
size_t nparsed;
nparsed = multipartparser_execute(&parser, &callbacks, data, size);
if (nparsed != size) {
/* parse error */
}See joyent/http-parser's README
to understand how to use callbacks especially for on_header_field and on_header_value.