cortav  Check-in [b4009ca1bd]

#pragma once

#include <lua.h>
#include <lauxlib.h>

#include <stddef.h>
#include <stdbool.h>
#include <stdint.h>

#define _luafn(name) static int LX_##name (lua_State* l)
#define _export(name) lua_pushcfunction(l, LX_##name), lua_setfield(l, -2, #name);

#define _luaret_bool(b) {lua_pushboolean(l, b); return 1;}
#define _luaAPI(mod, ...) int luaopen_bind_##mod (lua_State* l) { \
	lua_newtable(l); \
	__VA_ARGS__; \
	return 1; \
}

/* this comment serves only to unfuck a GCC bug */

#include "bind.h"

#include <curl/curl.h>

#define _str(...) #__VA_ARGS__
#define _e_tag "(native-bind " __FILE__ ":" _str(__LINE__) ") "

static size_t
buffer_string
(	char*  ptr,
	size_t size,
	size_t nmemb,
	void*  dest
) {
	luaL_Buffer* const data = dest;
	luaL_addlstring(data, ptr, size*nmemb);
	return size*nmemb;
}

_luafn(fetchURI) {
	const char* p_uri = luaL_checkstring(l,1);

	CURL* h = curl_easy_init();
	if (!h) {
		lua_pushstring(l, _e_tag "libcurl failed to init");
		lua_error(l);
	}

// 	int unwind = lua_gettop(l);
	luaL_Buffer download;
	luaL_buffinit(l, &download);

	char ebuf [CURL_ERROR_SIZE];
	curl_easy_setopt(h, CURLOPT_URL,           p_uri);
	curl_easy_setopt(h, CURLOPT_WRITEFUNCTION, buffer_string);
	curl_easy_setopt(h, CURLOPT_WRITEDATA,     &download);
	curl_easy_setopt(h, CURLOPT_FOLLOWLOCATION,true);
	curl_easy_setopt(h, CURLOPT_ERRORBUFFER,   ebuf);

	CURLcode e = curl_easy_perform(h);
	if (e == 0) {
		curl_easy_cleanup(h);
		luaL_pushresult(&download);
		return 1;
	} else {
// 		lua_settop(l,unwind);
		lua_pushnil(l);
		lua_pushstring(l, ebuf);
		return 2;
	}
}

_luaAPI(net,
  _export(fetchURI));

#include "bind.h"

#include <unistd.h>
#include <stdio.h>
#include <assert.h>

_luafn(getcwd) { /* getcwd() */
	size_t bufsz = 256;
	/* VLA resize hack */ for (;;) {
		char cwd [bufsz];
		if (getcwd(cwd, bufsz) == NULL) {
			assert(bufsz < (2 * 1024*1024)); /* sanity check */
			bufsz = bufsz * 2;
			continue;
		}
		lua_pushstring(l, cwd);
		return 1;
	}
}

_luafn(isatty) { /* isatty(stream) */
	luaL_Stream* stream = lua_touserdata(l, 1);
	if (stream == NULL) return 0;
	int fd = fileno(stream -> f);
	_luaret_bool(isatty(fd));
}

_luaAPI(posix,
	_export(getcwd);
	_export(isatty));

#include "bind.h"

_luafn(rangematch) {
	luaL_checkstring(l, 1);
	luaL_checknumber(l, 2);
	luaL_checkstring(l, 3);

	size_t strl = 0, matl = 0, start = lua_tointeger(l, 2)-1;
	const char* str = lua_tolstring(l, 1, &strl);
	const char* mat = lua_tolstring(l, 3, &matl);
	size_t to;
	if (start > strl || (to = start + matl) > strl) {
		_luaret_bool(false);
	}
	for (size_t i = start; i<to; ++i) {
		if (str[i] != mat[i - start]) _luaret_bool(false);
	}
	_luaret_bool(true);
}

_luaAPI(strutils, _export(rangematch));

{pkgs ? import <nixpkgs> {}, ...}:

let debuggable = d: d.overrideAttrs(o: rec {
	dontStrip = true;
});

in pkgs.mkShell {
	buildInputs = with pkgs; [
		lua5_4
		curl
	];
	shellHook = ''
		exec fish
	'';
	NIX_ENFORCE_PURITY = false;
}