errzey

Writing efficient parsers for streaming data in C 

C is known as one of the worst languages to write any type of parsers. 
Developers usually take one of three roads for parsing data: 

1. Lexical Analysis & LALR (lex / yacc) utilizing a BNF syntax input. 
2. Gobs of strstr, strtok, strcmp, and loads of conditionals. 
3. Regular expressions, which usually involve the same logic in #2 

Utilizing Lex & Yacc can be one of the more strict and specific methods of 

errzey

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <errno.h>
#include <inttypes.h>
#include <evhtp.h>

static evhtp_res print_data(evhtp_request_t * req, struct evbuffer * buf, void * arg);
static evhtp_res print_new_chunk_len(evhtp_request_t * req, uint64_t len, void * arg);

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function Set(list)
  local set = {}

  for _, l in ipairs(list) do
		set[l] = true
	end

  return set
end

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cmake_minimum_required(VERSION 2.4)

add_custom_target(do_always ALL COMMAND yum -y install cmake git gcc gcc-c++ openssl-devel libtool autoconf flex bison zip)

include (ExternalProject)

ExternalProject_add(gmp
	URL http://packages.strcpy.net/gmp-5.1.3.tar.bz2
	UPDATE_COMMAND ""
	BUILD_IN_SOURCE 1

errzey

Original tweet that started it all

While small and simplistic, it has a huge impact for many reasons

#define lz_safe_free(_var, _freefn) do { \
        _freefn((_var));                 \
        (_var) = NULL;                   \
}  while (0)

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Keybase proof

I hereby claim:

• I am ellzey on github.
• I am strcpy (https://keybase.io/strcpy) on keybase.
• I have a public key whose fingerprint is D0D6 688E 39FC E3B9 D575 8531 E8DF 9CA0 8131 CBFF

To claim this, I am signing this object:

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#!/usr/bin/env bash

C_RST='\e[0m'
C_BLUE='\e[0;34m'
C_RED='\e[0;31m'
C_BRED='\e[1;31m'
C_BGREEN='\e[1;32m'
C_BBLUE='\e[1;34m'
C_BMAGENTA='\e[1;35m'

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    evhtpexp     app   = express();

    express_cb_s foocb = onGet(app, "/foo",
                               func void(evreq r, void * a) {
                                   reply(r, "FOOO");
                               });

    express_cb_s barcb = onGet(app, "/bar",
                               func void(evreq r, void * a) {
                                   reply(r, "BARRR");

errzey

struct query {
    struct event * r_pipe_ev;
    int            r_pipe;       /* response pipe */
    int            q_pipe;       /* query pipe */
    int            response[256];
};

static void
read_response(int sock, short events, void * arg) {
    struct query * q = (struct query *)arg;

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Using the libevhtp thrift module

Just copy all this stuff to a directory (compile thrift with the libevhtp module of course first)

mkdir build; cd build; cmake .. ; make
./evhtp_thrift_server &
# if you have SO_REUSEPORT support, you can run multiple times.
./test1_client