diff options
Diffstat (limited to 'package/uhttpd/src/uhttpd-lua.c')
-rw-r--r-- | package/uhttpd/src/uhttpd-lua.c | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/package/uhttpd/src/uhttpd-lua.c b/package/uhttpd/src/uhttpd-lua.c new file mode 100644 index 0000000..ab09841 --- /dev/null +++ b/package/uhttpd/src/uhttpd-lua.c @@ -0,0 +1,541 @@ +/* + * uhttpd - Tiny single-threaded httpd - Lua handler + * + * Copyright (C) 2010 Jo-Philipp Wich <xm@subsignal.org> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "uhttpd.h" +#include "uhttpd-utils.h" +#include "uhttpd-lua.h" + + +static int uh_lua_recv(lua_State *L) +{ + size_t length; + char buffer[UH_LIMIT_MSGHEAD]; + ssize_t rlen = 0; + fd_set reader; + struct timeval timeout; + + length = luaL_checknumber(L, 1); + + if( (length > 0) && (length <= sizeof(buffer)) ) + { + FD_ZERO(&reader); + FD_SET(fileno(stdin), &reader); + + /* fail after 0.1s */ + timeout.tv_sec = 0; + timeout.tv_usec = 100000; + + /* check whether fd is readable */ + if( select(fileno(stdin) + 1, &reader, NULL, NULL, &timeout) > 0 ) + { + /* receive data */ + rlen = read(fileno(stdin), buffer, length); + lua_pushnumber(L, rlen); + + if( rlen > 0 ) + { + lua_pushlstring(L, buffer, rlen); + return 2; + } + + return 1; + } + + /* no, timeout and actually no data */ + lua_pushnumber(L, -2); + return 1; + } + + /* parameter error */ + lua_pushnumber(L, -3); + return 1; +} + +static int uh_lua_send_common(lua_State *L, int chunked) +{ + size_t length; + const char *buffer; + char chunk[16]; + ssize_t slen = 0; + + buffer = luaL_checklstring(L, 1, &length); + + if( chunked ) + { + if( length > 0 ) + { + snprintf(chunk, sizeof(chunk), "%X\r\n", length); + slen = write(fileno(stdout), chunk, strlen(chunk)); + slen += write(fileno(stdout), buffer, length); + slen += write(fileno(stdout), "\r\n", 2); + } + else + { + slen = write(fileno(stdout), "0\r\n\r\n", 5); + } + } + else + { + slen = write(fileno(stdout), buffer, length); + } + + lua_pushnumber(L, slen); + return 1; +} + +static int uh_lua_send(lua_State *L) +{ + return uh_lua_send_common(L, 0); +} + +static int uh_lua_sendc(lua_State *L) +{ + return uh_lua_send_common(L, 1); +} + +static int uh_lua_urldecode(lua_State *L) +{ + size_t inlen, outlen; + const char *inbuf; + char outbuf[UH_LIMIT_MSGHEAD]; + + inbuf = luaL_checklstring(L, 1, &inlen); + outlen = uh_urldecode(outbuf, sizeof(outbuf), inbuf, inlen); + + lua_pushlstring(L, outbuf, outlen); + return 1; +} + + +lua_State * uh_lua_init(const char *handler) +{ + lua_State *L = lua_open(); + const char *err_str = NULL; + + /* Load standard libaries */ + luaL_openlibs(L); + + /* build uhttpd api table */ + lua_newtable(L); + + /* register global send and receive functions */ + lua_pushcfunction(L, uh_lua_recv); + lua_setfield(L, -2, "recv"); + + lua_pushcfunction(L, uh_lua_send); + lua_setfield(L, -2, "send"); + + lua_pushcfunction(L, uh_lua_sendc); + lua_setfield(L, -2, "sendc"); + + lua_pushcfunction(L, uh_lua_urldecode); + lua_setfield(L, -2, "urldecode"); + + /* _G.uhttpd = { ... } */ + lua_setfield(L, LUA_GLOBALSINDEX, "uhttpd"); + + + /* load Lua handler */ + switch( luaL_loadfile(L, handler) ) + { + case LUA_ERRSYNTAX: + fprintf(stderr, + "Lua handler contains syntax errors, unable to continue\n"); + exit(1); + + case LUA_ERRMEM: + fprintf(stderr, + "Lua handler ran out of memory, unable to continue\n"); + exit(1); + + case LUA_ERRFILE: + fprintf(stderr, + "Lua cannot open the handler script, unable to continue\n"); + exit(1); + + default: + /* compile Lua handler */ + switch( lua_pcall(L, 0, 0, 0) ) + { + case LUA_ERRRUN: + err_str = luaL_checkstring(L, -1); + fprintf(stderr, + "Lua handler had runtime error, unable to continue\n" + "Error: %s\n", err_str + ); + exit(1); + + case LUA_ERRMEM: + err_str = luaL_checkstring(L, -1); + fprintf(stderr, + "Lua handler ran out of memory, unable to continue\n" + "Error: %s\n", err_str + ); + exit(1); + + default: + /* test handler function */ + lua_getglobal(L, UH_LUA_CALLBACK); + + if( ! lua_isfunction(L, -1) ) + { + fprintf(stderr, + "Lua handler provides no " UH_LUA_CALLBACK "(), unable to continue\n"); + exit(1); + } + + lua_pop(L, 1); + break; + } + + break; + } + + return L; +} + +void uh_lua_request(struct client *cl, struct http_request *req, lua_State *L) +{ + int i, data_sent; + int content_length = 0; + int buflen = 0; + int fd_max = 0; + char *query_string; + const char *prefix = cl->server->conf->lua_prefix; + const char *err_str = NULL; + + int rfd[2] = { 0, 0 }; + int wfd[2] = { 0, 0 }; + + char buf[UH_LIMIT_MSGHEAD]; + + pid_t child; + + fd_set reader; + fd_set writer; + + struct sigaction sa; + struct timeval timeout; + + + /* spawn pipes for me->child, child->me */ + if( (pipe(rfd) < 0) || (pipe(wfd) < 0) ) + { + uh_http_sendhf(cl, 500, "Internal Server Error", + "Failed to create pipe: %s", strerror(errno)); + + if( rfd[0] > 0 ) close(rfd[0]); + if( rfd[1] > 0 ) close(rfd[1]); + if( wfd[0] > 0 ) close(wfd[0]); + if( wfd[1] > 0 ) close(wfd[1]); + + return; + } + + + switch( (child = fork()) ) + { + case -1: + uh_http_sendhf(cl, 500, "Internal Server Error", + "Failed to fork child: %s", strerror(errno)); + break; + + case 0: + /* restore SIGTERM */ + sa.sa_flags = 0; + sa.sa_handler = SIG_DFL; + sigemptyset(&sa.sa_mask); + sigaction(SIGTERM, &sa, NULL); + + /* close loose pipe ends */ + close(rfd[0]); + close(wfd[1]); + + /* patch stdout and stdin to pipes */ + dup2(rfd[1], 1); + dup2(wfd[0], 0); + + /* put handler callback on stack */ + lua_getglobal(L, UH_LUA_CALLBACK); + + /* build env table */ + lua_newtable(L); + + /* request method */ + switch(req->method) + { + case UH_HTTP_MSG_GET: + lua_pushstring(L, "GET"); + break; + + case UH_HTTP_MSG_HEAD: + lua_pushstring(L, "HEAD"); + break; + + case UH_HTTP_MSG_POST: + lua_pushstring(L, "POST"); + break; + } + + lua_setfield(L, -2, "REQUEST_METHOD"); + + /* request url */ + lua_pushstring(L, req->url); + lua_setfield(L, -2, "REQUEST_URI"); + + /* script name */ + lua_pushstring(L, cl->server->conf->lua_prefix); + lua_setfield(L, -2, "SCRIPT_NAME"); + + /* query string, path info */ + if( (query_string = strchr(req->url, '?')) != NULL ) + { + lua_pushstring(L, query_string + 1); + lua_setfield(L, -2, "QUERY_STRING"); + + if( (int)(query_string - req->url) > strlen(prefix) ) + { + lua_pushlstring(L, + &req->url[strlen(prefix)], + (int)(query_string - req->url) - strlen(prefix) + ); + + lua_setfield(L, -2, "PATH_INFO"); + } + } + else if( strlen(req->url) > strlen(prefix) ) + { + lua_pushstring(L, &req->url[strlen(prefix)]); + lua_setfield(L, -2, "PATH_INFO"); + } + + /* http protcol version */ + lua_pushnumber(L, floor(req->version * 10) / 10); + lua_setfield(L, -2, "HTTP_VERSION"); + + if( req->version > 1.0 ) + lua_pushstring(L, "HTTP/1.1"); + else + lua_pushstring(L, "HTTP/1.0"); + + lua_setfield(L, -2, "SERVER_PROTOCOL"); + + + /* address information */ + lua_pushstring(L, sa_straddr(&cl->peeraddr)); + lua_setfield(L, -2, "REMOTE_ADDR"); + + lua_pushinteger(L, sa_port(&cl->peeraddr)); + lua_setfield(L, -2, "REMOTE_PORT"); + + lua_pushstring(L, sa_straddr(&cl->servaddr)); + lua_setfield(L, -2, "SERVER_ADDR"); + + lua_pushinteger(L, sa_port(&cl->servaddr)); + lua_setfield(L, -2, "SERVER_PORT"); + + /* essential env vars */ + foreach_header(i, req->headers) + { + if( !strcasecmp(req->headers[i], "Content-Length") ) + { + lua_pushnumber(L, atoi(req->headers[i+1])); + lua_setfield(L, -2, "CONTENT_LENGTH"); + } + else if( !strcasecmp(req->headers[i], "Content-Type") ) + { + lua_pushstring(L, req->headers[i+1]); + lua_setfield(L, -2, "CONTENT_TYPE"); + } + } + + /* misc. headers */ + lua_newtable(L); + + foreach_header(i, req->headers) + { + if( strcasecmp(req->headers[i], "Content-Length") && + strcasecmp(req->headers[i], "Content-Type") + ) { + lua_pushstring(L, req->headers[i+1]); + lua_setfield(L, -2, req->headers[i]); + } + } + + lua_setfield(L, -2, "headers"); + + + /* call */ + switch( lua_pcall(L, 1, 0, 0) ) + { + case LUA_ERRMEM: + case LUA_ERRRUN: + err_str = luaL_checkstring(L, -1); + + if( ! err_str ) + err_str = "Unknown error"; + + printf( + "HTTP/%.1f 500 Internal Server Error\r\n" + "Connection: close\r\n" + "Content-Type: text/plain\r\n" + "Content-Length: %i\r\n\r\n" + "Lua raised a runtime error:\n %s\n", + req->version, 31 + strlen(err_str), err_str + ); + + break; + + default: + break; + } + + close(wfd[0]); + close(rfd[1]); + exit(0); + + break; + + /* parent; handle I/O relaying */ + default: + /* close unneeded pipe ends */ + close(rfd[1]); + close(wfd[0]); + + /* max watch fd */ + fd_max = max(rfd[0], wfd[1]) + 1; + + /* find content length */ + if( req->method == UH_HTTP_MSG_POST ) + { + foreach_header(i, req->headers) + { + if( ! strcasecmp(req->headers[i], "Content-Length") ) + { + content_length = atoi(req->headers[i+1]); + break; + } + } + } + + +#define ensure(x) \ + do { if( x < 0 ) goto out; } while(0) + + data_sent = 0; + + /* I/O loop, watch our pipe ends and dispatch child reads/writes from/to socket */ + while( 1 ) + { + FD_ZERO(&reader); + FD_ZERO(&writer); + + FD_SET(rfd[0], &reader); + FD_SET(wfd[1], &writer); + + timeout.tv_sec = 15; + timeout.tv_usec = 0; + + /* wait until we can read or write or both */ + if( select(fd_max, &reader, (content_length > -1) ? &writer : NULL, NULL, &timeout) > 0 ) + { + /* ready to write to Lua child */ + if( FD_ISSET(wfd[1], &writer) ) + { + /* there is unread post data waiting */ + if( content_length > 0 ) + { + /* read it from socket ... */ + if( (buflen = uh_tcp_recv(cl, buf, min(content_length, sizeof(buf)))) > 0 ) + { + /* ... and write it to child's stdin */ + if( write(wfd[1], buf, buflen) < 0 ) + perror("write()"); + + content_length -= buflen; + } + + /* unexpected eof! */ + else + { + if( write(wfd[1], "", 0) < 0 ) + perror("write()"); + + content_length = 0; + } + } + + /* there is no more post data, close pipe to child's stdin */ + else if( content_length > -1 ) + { + close(wfd[1]); + content_length = -1; + } + } + + /* ready to read from Lua child */ + if( FD_ISSET(rfd[0], &reader) ) + { + /* read data from child ... */ + if( (buflen = read(rfd[0], buf, sizeof(buf))) > 0 ) + { + /* pass through buffer to socket */ + ensure(uh_tcp_send(cl, buf, buflen)); + data_sent = 1; + } + + /* looks like eof from child */ + else + { + /* error? */ + if( ! data_sent ) + uh_http_sendhf(cl, 500, "Internal Server Error", + "The Lua child did not produce any response"); + + break; + } + } + } + + /* no activity for 15 seconds... looks dead */ + else + { + ensure(uh_http_sendhf(cl, 504, "Gateway Timeout", + "The Lua handler took too long to produce a response")); + + break; + } + } + + out: + close(rfd[0]); + close(wfd[1]); + + if( !kill(child, 0) ) + kill(child, SIGTERM); + + break; + } +} + +void uh_lua_close(lua_State *L) +{ + lua_close(L); +} + + |