src/mod_magnet.c

   1 #include "first.h"
   2
   3 #include "base.h"
   4 #include "log.h"
   5 #include "buffer.h"
   6 #include "http_chunk.h"
   7
   8 #include "plugin.h"
   9
  10 #include "mod_magnet_cache.h"
  11 #include "response.h"
  12 #include "stat_cache.h"
  13 #include "status_counter.h"
  14 #include "etag.h"
  15
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <setjmp.h>
  19
  20 #include <lua.h>
  21 #include <lauxlib.h>
  22
  23 #define LUA_RIDX_LIGHTTPD_SERVER     "lighty.srv"
  24 #define LUA_RIDX_LIGHTTPD_CONNECTION "lighty.con"
  25
  26 #define MAGNET_CONFIG_RAW_URL       "magnet.attract-raw-url-to"
  27 #define MAGNET_CONFIG_PHYSICAL_PATH "magnet.attract-physical-path-to"
  28 #define MAGNET_RESTART_REQUEST      99
  29
  30 /* plugin config for all request/connections */
  31
  32 static jmp_buf exceptionjmp;
  33
  34 typedef struct {
  35         array *url_raw;
  36         array *physical_path;
  37 } plugin_config;
  38
  39 typedef struct {
  40         PLUGIN_DATA;
  41
  42         script_cache *cache;
  43
  44         buffer *encode_buf;
  45
  46         plugin_config **config_storage;
  47
  48         plugin_config conf;
  49 } plugin_data;
  50
  51 /* init the plugin data */
  52 INIT_FUNC(mod_magnet_init) {
  53         plugin_data *p;
  54
  55         p = calloc(1, sizeof(*p));
  56
  57         p->cache = script_cache_init();
  58         p->encode_buf = buffer_init();
  59
  60         return p;
  61 }
  62
  63 /* detroy the plugin data */
  64 FREE_FUNC(mod_magnet_free) {
  65         plugin_data *p = p_d;
  66
  67         UNUSED(srv);
  68
  69         if (!p) return HANDLER_GO_ON;
  70
  71         if (p->config_storage) {
  72                 size_t i;
  73
  74                 for (i = 0; i < srv->config_context->used; i++) {
  75                         plugin_config *s = p->config_storage[i];
  76
  77                         if (NULL == s) continue;
  78
  79                         array_free(s->url_raw);
  80                         array_free(s->physical_path);
  81
  82                         free(s);
  83                 }
  84                 free(p->config_storage);
  85         }
  86
  87         script_cache_free(p->cache);
  88         buffer_free(p->encode_buf);
  89
  90         free(p);
  91
  92         return HANDLER_GO_ON;
  93 }
  94
  95 /* handle plugin config and check values */
  96
  97 SETDEFAULTS_FUNC(mod_magnet_set_defaults) {
  98         plugin_data *p = p_d;
  99         size_t i = 0;
 100
 101         config_values_t cv[] = {
 102                 { MAGNET_CONFIG_RAW_URL,       NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION },       /* 0 */
 103                 { MAGNET_CONFIG_PHYSICAL_PATH, NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION },       /* 1 */
 104                 { NULL,                           NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET }
 105         };
 106
 107         if (!p) return HANDLER_ERROR;
 108
 109         p->config_storage = calloc(1, srv->config_context->used * sizeof(plugin_config *));
 110
 111         for (i = 0; i < srv->config_context->used; i++) {
 112                 data_config const* config = (data_config const*)srv->config_context->data[i];
 113                 plugin_config *s;
 114
 115                 s = calloc(1, sizeof(plugin_config));
 116                 s->url_raw  = array_init();
 117                 s->physical_path = array_init();
 118
 119                 cv[0].destination = s->url_raw;
 120                 cv[1].destination = s->physical_path;
 121
 122                 p->config_storage[i] = s;
 123
 124                 if (0 != config_insert_values_global(srv, config->value, cv, i == 0 ? T_CONFIG_SCOPE_SERVER : T_CONFIG_SCOPE_CONNECTION)) {
 125                         return HANDLER_ERROR;
 126                 }
 127
 128                 if (!array_is_vlist(s->url_raw)) {
 129                         log_error_write(srv, __FILE__, __LINE__, "s",
 130                                         "unexpected value for magnet.attract-raw-url-to; expected list of \"scriptpath\"");
 131                         return HANDLER_ERROR;
 132                 }
 133
 134                 if (!array_is_vlist(s->physical_path)) {
 135                         log_error_write(srv, __FILE__, __LINE__, "s",
 136                                         "unexpected value for magnet.attract-physical-path-to; expected list \"scriptpath\"");
 137                         return HANDLER_ERROR;
 138                 }
 139         }
 140
 141         return HANDLER_GO_ON;
 142 }
 143
 144 #define PATCH(x) \
 145         p->conf.x = s->x;
 146 static int mod_magnet_patch_connection(server *srv, connection *con, plugin_data *p) {
 147         size_t i, j;
 148         plugin_config *s = p->config_storage[0];
 149
 150         PATCH(url_raw);
 151         PATCH(physical_path);
 152
 153         /* skip the first, the global context */
 154         for (i = 1; i < srv->config_context->used; i++) {
 155                 data_config *dc = (data_config *)srv->config_context->data[i];
 156                 s = p->config_storage[i];
 157
 158                 /* condition didn't match */
 159                 if (!config_check_cond(srv, con, dc)) continue;
 160
 161                 /* merge config */
 162                 for (j = 0; j < dc->value->used; j++) {
 163                         data_unset *du = dc->value->data[j];
 164
 165                         if (buffer_is_equal_string(du->key, CONST_STR_LEN(MAGNET_CONFIG_RAW_URL))) {
 166                                 PATCH(url_raw);
 167                         } else if (buffer_is_equal_string(du->key, CONST_STR_LEN(MAGNET_CONFIG_PHYSICAL_PATH))) {
 168                                 PATCH(physical_path);
 169                         }
 170                 }
 171         }
 172
 173         return 0;
 174 }
 175 #undef PATCH
 176
 177 #if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM < 502
 178 /* lua5.1 backward compat definition */
 179 static void lua_pushglobaltable(lua_State *L) { /* (-0, +1, -) */
 180         lua_pushvalue(L, LUA_GLOBALSINDEX);
 181 }
 182 #endif
 183
 184 static void magnet_setfenv_mainfn(lua_State *L, int funcIndex) { /* (-1, 0, -) */
 185 #if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM >= 502
 186         /* set "_ENV" upvalue, which should be the first upvalue of a "main" lua
 187          * function if it uses any global names
 188          */
 189
 190         const char* first_upvalue_name = lua_getupvalue(L, funcIndex, 1);
 191         if (NULL == first_upvalue_name) return; /* doesn't have any upvalues */
 192         lua_pop(L, 1); /* only need the name of the upvalue, not the value */
 193
 194         if (0 != strcmp(first_upvalue_name, "_ENV")) return;
 195
 196         if (NULL == lua_setupvalue(L, funcIndex, 1)) {
 197                 /* pop value if lua_setupvalue didn't set the (not existing) upvalue */
 198                 lua_pop(L, 1);
 199         }
 200 #else
 201         lua_setfenv(L, funcIndex);
 202 #endif
 203 }
 204
 205 #if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM < 502
 206 /* lua 5.2 already supports __pairs */
 207
 208 /* See http://lua-users.org/wiki/GeneralizedPairsAndIpairs for implementation details.
 209  * Override the default pairs() function to allow us to use a __pairs metakey
 210  */
 211 static int magnet_pairs(lua_State *L) {
 212         luaL_checkany(L, 1); /* "self" */
 213
 214         if (luaL_getmetafield(L, 1, "__pairs")) {
 215                 /* call __pairs(self) */
 216                 lua_pushvalue(L, 1);
 217                 lua_call(L, 1, 3);
 218         } else {
 219                 /* call <original-pairs-method>(self) */
 220                 lua_pushvalue(L, lua_upvalueindex(1));
 221                 lua_pushvalue(L, 1);
 222                 lua_call(L, 1, 3);
 223         }
 224         return 3;
 225 }
 226 #endif
 227
 228 /* Define a function that will iterate over an array* (in upval 1) using current position (upval 2) */
 229 static int magnet_array_next(lua_State *L) {
 230         data_unset *du;
 231         data_string *ds;
 232         data_integer *di;
 233
 234         size_t pos = lua_tointeger(L, lua_upvalueindex(1));
 235         array *a = lua_touserdata(L, lua_upvalueindex(2));
 236
 237         lua_settop(L, 0);
 238
 239         if (pos >= a->used) return 0;
 240         if (NULL != (du = a->data[pos])) {
 241                 lua_pushlstring(L, CONST_BUF_LEN(du->key));
 242                 switch (du->type) {
 243                         case TYPE_STRING:
 244                                 ds = (data_string *)du;
 245                                 if (!buffer_is_empty(ds->value)) {
 246                                         lua_pushlstring(L, CONST_BUF_LEN(ds->value));
 247                                 } else {
 248                                         lua_pushnil(L);
 249                                 }
 250                                 break;
 251                         case TYPE_INTEGER:
 252                                 di = (data_integer *)du;
 253                                 lua_pushinteger(L, di->value);
 254                                 break;
 255                         default:
 256                                 lua_pushnil(L);
 257                                 break;
 258                 }
 259
 260                 /* Update our positional upval to reflect our new current position */
 261                 pos++;
 262                 lua_pushinteger(L, pos);
 263                 lua_replace(L, lua_upvalueindex(1));
 264
 265                 /* Returning 2 items on the stack (key, value) */
 266                 return 2;
 267         }
 268         return 0;
 269 }
 270
 271 /* Create the closure necessary to iterate over the array *a with the above function */
 272 static int magnet_array_pairs(lua_State *L, array *a) {
 273         lua_pushinteger(L, 0); /* Push our current pos (the start) into upval 1 */
 274         lua_pushlightuserdata(L, a); /* Push our array *a into upval 2 */
 275         lua_pushcclosure(L, magnet_array_next, 2); /* Push our new closure with 2 upvals */
 276         return 1;
 277 }
 278
 279 static server* magnet_get_server(lua_State *L) {
 280         server *srv;
 281
 282         lua_getfield(L, LUA_REGISTRYINDEX, LUA_RIDX_LIGHTTPD_SERVER);
 283         srv = lua_touserdata(L, -1);
 284         lua_pop(L, 1);
 285
 286         return srv;
 287 }
 288
 289 static connection* magnet_get_connection(lua_State *L) {
 290         connection *con;
 291
 292         lua_getfield(L, LUA_REGISTRYINDEX, LUA_RIDX_LIGHTTPD_CONNECTION);
 293         con = lua_touserdata(L, -1);
 294         lua_pop(L, 1);
 295
 296         return con;
 297 }
 298
 299 typedef struct {
 300         const char *ptr;
 301         size_t len;
 302 } const_buffer;
 303
 304 static const_buffer magnet_checkconstbuffer(lua_State *L, int index) {
 305         const_buffer cb;
 306         cb.ptr = luaL_checklstring(L, index, &cb.len);
 307         return cb;
 308 }
 309
 310 static buffer* magnet_checkbuffer(lua_State *L, int index) {
 311         const_buffer cb = magnet_checkconstbuffer(L, index);
 312         buffer *b = buffer_init();
 313         buffer_copy_string_len(b, cb.ptr, cb.len);
 314         return b;
 315 }
 316
 317 static int magnet_print(lua_State *L) {
 318         buffer *b = magnet_checkbuffer(L, 1);
 319
 320         log_error_write(magnet_get_server(L), __FILE__, __LINE__, "sB",
 321                 "(lua-print)",
 322                 b);
 323
 324         buffer_free(b);
 325
 326         return 0;
 327 }
 328
 329 static int magnet_stat(lua_State *L) {
 330         buffer *sb = magnet_checkbuffer(L, 1);
 331         server *srv = magnet_get_server(L);
 332         connection *con = magnet_get_connection(L);
 333         stat_cache_entry *sce = NULL;
 334         handler_t res;
 335
 336         res = stat_cache_get_entry(srv, con, sb, &sce);
 337         buffer_free(sb);
 338
 339         if (HANDLER_GO_ON != res) {
 340                 lua_pushnil(L);
 341                 return 1;
 342         }
 343
 344         lua_newtable(L); // return value
 345
 346         lua_pushboolean(L, S_ISREG(sce->st.st_mode));
 347         lua_setfield(L, -2, "is_file");
 348
 349         lua_pushboolean(L, S_ISDIR(sce->st.st_mode));
 350         lua_setfield(L, -2, "is_dir");
 351
 352         lua_pushboolean(L, S_ISCHR(sce->st.st_mode));
 353         lua_setfield(L, -2, "is_char");
 354
 355         lua_pushboolean(L, S_ISBLK(sce->st.st_mode));
 356         lua_setfield(L, -2, "is_block");
 357
 358         lua_pushboolean(L, S_ISSOCK(sce->st.st_mode));
 359         lua_setfield(L, -2, "is_socket");
 360
 361         lua_pushboolean(L, S_ISLNK(sce->st.st_mode));
 362         lua_setfield(L, -2, "is_link");
 363
 364         lua_pushboolean(L, S_ISFIFO(sce->st.st_mode));
 365         lua_setfield(L, -2, "is_fifo");
 366
 367         lua_pushinteger(L, sce->st.st_mtime);
 368         lua_setfield(L, -2, "st_mtime");
 369
 370         lua_pushinteger(L, sce->st.st_ctime);
 371         lua_setfield(L, -2, "st_ctime");
 372
 373         lua_pushinteger(L, sce->st.st_atime);
 374         lua_setfield(L, -2, "st_atime");
 375
 376         lua_pushinteger(L, sce->st.st_uid);
 377         lua_setfield(L, -2, "st_uid");
 378
 379         lua_pushinteger(L, sce->st.st_gid);
 380         lua_setfield(L, -2, "st_gid");
 381
 382         lua_pushinteger(L, sce->st.st_size);
 383         lua_setfield(L, -2, "st_size");
 384
 385         lua_pushinteger(L, sce->st.st_ino);
 386         lua_setfield(L, -2, "st_ino");
 387
 388         if (!buffer_string_is_empty(sce->etag)) {
 389                 /* we have to mutate the etag */
 390                 buffer *b = buffer_init();
 391                 etag_mutate(b, sce->etag);
 392
 393                 lua_pushlstring(L, CONST_BUF_LEN(b));
 394                 buffer_free(b);
 395         } else {
 396                 lua_pushnil(L);
 397         }
 398         lua_setfield(L, -2, "etag");
 399
 400         if (!buffer_string_is_empty(sce->content_type)) {
 401                 lua_pushlstring(L, CONST_BUF_LEN(sce->content_type));
 402         } else {
 403                 lua_pushnil(L);
 404         }
 405         lua_setfield(L, -2, "content-type");
 406
 407         return 1;
 408 }
 409
 410
 411 static int magnet_atpanic(lua_State *L) {
 412         buffer *b = magnet_checkbuffer(L, 1);
 413
 414         log_error_write(magnet_get_server(L), __FILE__, __LINE__, "sB",
 415                 "(lua-atpanic)",
 416                 b);
 417
 418         buffer_free(b);
 419
 420         longjmp(exceptionjmp, 1);
 421 }
 422
 423 static int magnet_reqhdr_get(lua_State *L) {
 424         connection *con = magnet_get_connection(L);
 425         data_string *ds;
 426
 427         /* __index: param 1 is the (empty) table the value was not found in */
 428         size_t klen;
 429         const char *key = luaL_checklstring(L, 2, &klen);
 430
 431         if (NULL != (ds = (data_string *)array_get_element_klen(con->request.headers, key, klen))) {
 432                 if (!buffer_is_empty(ds->value)) {
 433                         lua_pushlstring(L, CONST_BUF_LEN(ds->value));
 434                 } else {
 435                         lua_pushnil(L);
 436                 }
 437         } else {
 438                 lua_pushnil(L);
 439         }
 440         return 1;
 441 }
 442
 443 static int magnet_reqhdr_pairs(lua_State *L) {
 444         connection *con = magnet_get_connection(L);
 445
 446         return magnet_array_pairs(L, con->request.headers);
 447 }
 448
 449 static int magnet_status_get(lua_State *L) {
 450         data_integer *di;
 451         server *srv = magnet_get_server(L);
 452
 453         /* __index: param 1 is the (empty) table the value was not found in */
 454         const_buffer key = magnet_checkconstbuffer(L, 2);
 455
 456         di = status_counter_get_counter(srv, key.ptr, key.len);
 457
 458         lua_pushinteger(L, (lua_Integer)di->value);
 459
 460         return 1;
 461 }
 462
 463 static int magnet_status_set(lua_State *L) {
 464         server *srv = magnet_get_server(L);
 465
 466         /* __newindex: param 1 is the (empty) table the value is supposed to be set in */
 467         const_buffer key = magnet_checkconstbuffer(L, 2);
 468         int counter = (int) luaL_checkinteger(L, 3);
 469
 470         status_counter_set(srv, key.ptr, key.len, counter);
 471
 472         return 0;
 473 }
 474
 475 static int magnet_status_pairs(lua_State *L) {
 476         server *srv = magnet_get_server(L);
 477
 478         return magnet_array_pairs(L, srv->status);
 479 }
 480
 481 typedef struct {
 482         const char *name;
 483         enum {
 484                 MAGNET_ENV_UNSET,
 485
 486                 MAGNET_ENV_PHYICAL_PATH,
 487                 MAGNET_ENV_PHYICAL_REL_PATH,
 488                 MAGNET_ENV_PHYICAL_DOC_ROOT,
 489                 MAGNET_ENV_PHYICAL_BASEDIR,
 490
 491                 MAGNET_ENV_URI_PATH,
 492                 MAGNET_ENV_URI_PATH_RAW,
 493                 MAGNET_ENV_URI_SCHEME,
 494                 MAGNET_ENV_URI_AUTHORITY,
 495                 MAGNET_ENV_URI_QUERY,
 496
 497                 MAGNET_ENV_REQUEST_METHOD,
 498                 MAGNET_ENV_REQUEST_URI,
 499                 MAGNET_ENV_REQUEST_ORIG_URI,
 500                 MAGNET_ENV_REQUEST_PATH_INFO,
 501                 MAGNET_ENV_REQUEST_REMOTE_IP,
 502                 MAGNET_ENV_REQUEST_PROTOCOL
 503         } type;
 504 } magnet_env_t;
 505
 506 static const magnet_env_t magnet_env[] = {
 507         { "physical.path", MAGNET_ENV_PHYICAL_PATH },
 508         { "physical.rel-path", MAGNET_ENV_PHYICAL_REL_PATH },
 509         { "physical.doc-root", MAGNET_ENV_PHYICAL_DOC_ROOT },
 510         { "physical.basedir", MAGNET_ENV_PHYICAL_BASEDIR },
 511
 512         { "uri.path", MAGNET_ENV_URI_PATH },
 513         { "uri.path-raw", MAGNET_ENV_URI_PATH_RAW },
 514         { "uri.scheme", MAGNET_ENV_URI_SCHEME },
 515         { "uri.authority", MAGNET_ENV_URI_AUTHORITY },
 516         { "uri.query", MAGNET_ENV_URI_QUERY },
 517
 518         { "request.method", MAGNET_ENV_REQUEST_METHOD },
 519         { "request.uri", MAGNET_ENV_REQUEST_URI },
 520         { "request.orig-uri", MAGNET_ENV_REQUEST_ORIG_URI },
 521         { "request.path-info", MAGNET_ENV_REQUEST_PATH_INFO },
 522         { "request.remote-ip", MAGNET_ENV_REQUEST_REMOTE_IP },
 523         { "request.protocol", MAGNET_ENV_REQUEST_PROTOCOL },
 524
 525         { NULL, MAGNET_ENV_UNSET }
 526 };
 527
 528 static buffer *magnet_env_get_buffer_by_id(server *srv, connection *con, int id) {
 529         buffer *dest = NULL;
 530
 531         UNUSED(srv);
 532
 533         /**
 534          * map all internal variables to lua
 535          *
 536          */
 537
 538         switch (id) {
 539         case MAGNET_ENV_PHYICAL_PATH: dest = con->physical.path; break;
 540         case MAGNET_ENV_PHYICAL_REL_PATH: dest = con->physical.rel_path; break;
 541         case MAGNET_ENV_PHYICAL_DOC_ROOT: dest = con->physical.doc_root; break;
 542         case MAGNET_ENV_PHYICAL_BASEDIR: dest = con->physical.basedir; break;
 543
 544         case MAGNET_ENV_URI_PATH: dest = con->uri.path; break;
 545         case MAGNET_ENV_URI_PATH_RAW: dest = con->uri.path_raw; break;
 546         case MAGNET_ENV_URI_SCHEME: dest = con->uri.scheme; break;
 547         case MAGNET_ENV_URI_AUTHORITY: dest = con->uri.authority; break;
 548         case MAGNET_ENV_URI_QUERY: dest = con->uri.query; break;
 549
 550         case MAGNET_ENV_REQUEST_METHOD:
 551                 buffer_copy_string(srv->tmp_buf, get_http_method_name(con->request.http_method));
 552                 dest = srv->tmp_buf;
 553                 break;
 554         case MAGNET_ENV_REQUEST_URI:      dest = con->request.uri; break;
 555         case MAGNET_ENV_REQUEST_ORIG_URI: dest = con->request.orig_uri; break;
 556         case MAGNET_ENV_REQUEST_PATH_INFO: dest = con->request.pathinfo; break;
 557         case MAGNET_ENV_REQUEST_REMOTE_IP: dest = con->dst_addr_buf; break;
 558         case MAGNET_ENV_REQUEST_PROTOCOL:
 559                 buffer_copy_string(srv->tmp_buf, get_http_version_name(con->request.http_version));
 560                 dest = srv->tmp_buf;
 561                 break;
 562
 563         case MAGNET_ENV_UNSET: break;
 564         }
 565
 566         return dest;
 567 }
 568
 569 static buffer *magnet_env_get_buffer(server *srv, connection *con, const char *key) {
 570         size_t i;
 571
 572         for (i = 0; magnet_env[i].name; i++) {
 573                 if (0 == strcmp(key, magnet_env[i].name)) break;
 574         }
 575
 576         return magnet_env_get_buffer_by_id(srv, con, magnet_env[i].type);
 577 }
 578
 579 static int magnet_env_get(lua_State *L) {
 580         server *srv = magnet_get_server(L);
 581         connection *con = magnet_get_connection(L);
 582
 583         /* __index: param 1 is the (empty) table the value was not found in */
 584         const char *key = luaL_checkstring(L, 2);
 585         buffer *dest = NULL;
 586
 587         dest = magnet_env_get_buffer(srv, con, key);
 588
 589         if (!buffer_is_empty(dest)) {
 590                 lua_pushlstring(L, CONST_BUF_LEN(dest));
 591         } else {
 592                 lua_pushnil(L);
 593         }
 594
 595         return 1;
 596 }
 597
 598 static int magnet_env_set(lua_State *L) {
 599         server *srv = magnet_get_server(L);
 600         connection *con = magnet_get_connection(L);
 601
 602         /* __newindex: param 1 is the (empty) table the value is supposed to be set in */
 603         const char *key = luaL_checkstring(L, 2);
 604         buffer *dest = NULL;
 605
 606         luaL_checkany(L, 3); /* nil or a string */
 607
 608         if (NULL != (dest = magnet_env_get_buffer(srv, con, key))) {
 609                 if (lua_isnil(L, 3)) {
 610                         buffer_reset(dest);
 611                 } else {
 612                         const_buffer val = magnet_checkconstbuffer(L, 3);
 613                         buffer_copy_string_len(dest, val.ptr, val.len);
 614                 }
 615         } else {
 616                 /* couldn't save */
 617
 618                 return luaL_error(L, "couldn't store '%s' in lighty.env[]", key);
 619         }
 620
 621         return 0;
 622 }
 623
 624 static int magnet_env_next(lua_State *L) {
 625         server *srv = magnet_get_server(L);
 626         connection *con = magnet_get_connection(L);
 627         const int pos = lua_tointeger(L, lua_upvalueindex(1));
 628
 629         buffer *dest;
 630
 631         /* ignore previous key: use upvalue for current pos */
 632         lua_settop(L, 0);
 633
 634         if (NULL == magnet_env[pos].name) return 0; /* end of list */
 635         /* Update our positional upval to reflect our new current position */
 636         lua_pushinteger(L, pos + 1);
 637         lua_replace(L, lua_upvalueindex(1));
 638
 639         /* key to return */
 640         lua_pushstring(L, magnet_env[pos].name);
 641
 642         /* get value */
 643         dest = magnet_env_get_buffer_by_id(srv, con, magnet_env[pos].type);
 644         if (!buffer_is_empty(dest)) {
 645                 lua_pushlstring(L, CONST_BUF_LEN(dest));
 646         } else {
 647                 lua_pushnil(L);
 648         }
 649
 650         /* return 2 items on the stack (key, value) */
 651         return 2;
 652 }
 653
 654 static int magnet_env_pairs(lua_State *L) {
 655         lua_pushinteger(L, 0); /* Push our current pos (the start) into upval 1 */
 656         lua_pushcclosure(L, magnet_env_next, 1); /* Push our new closure with 1 upvals */
 657         return 1;
 658 }
 659
 660 static int magnet_cgi_get(lua_State *L) {
 661         connection *con = magnet_get_connection(L);
 662         data_string *ds;
 663
 664         /* __index: param 1 is the (empty) table the value was not found in */
 665         size_t klen;
 666         const char *key = luaL_checklstring(L, 2, &klen);
 667
 668         ds = (data_string *)array_get_element_klen(con->environment, key, klen);
 669         if (NULL != ds && !buffer_is_empty(ds->value))
 670                 lua_pushlstring(L, CONST_BUF_LEN(ds->value));
 671         else
 672                 lua_pushnil(L);
 673
 674         return 1;
 675 }
 676
 677 static int magnet_cgi_set(lua_State *L) {
 678         connection *con = magnet_get_connection(L);
 679
 680         /* __newindex: param 1 is the (empty) table the value is supposed to be set in */
 681         const_buffer key = magnet_checkconstbuffer(L, 2);
 682         const_buffer val = magnet_checkconstbuffer(L, 3);
 683
 684         array_set_key_value(con->environment, key.ptr, key.len, val.ptr, val.len);
 685
 686         return 0;
 687 }
 688
 689 static int magnet_cgi_pairs(lua_State *L) {
 690         connection *con = magnet_get_connection(L);
 691
 692         return magnet_array_pairs(L, con->environment);
 693 }
 694
 695
 696 static int magnet_copy_response_header(server *srv, connection *con, lua_State *L, int lighty_table_ndx) {
 697         force_assert(lua_istable(L, lighty_table_ndx));
 698
 699         lua_getfield(L, lighty_table_ndx, "header"); /* lighty.header */
 700         if (lua_istable(L, -1)) {
 701                 /* header is found, and is a table */
 702
 703                 lua_pushnil(L);
 704                 while (lua_next(L, -2) != 0) {
 705                         if (lua_isstring(L, -1) && lua_isstring(L, -2)) {
 706                                 const_buffer key = magnet_checkconstbuffer(L, -2);
 707                                 const_buffer val = magnet_checkconstbuffer(L, -1);
 708
 709                                 response_header_overwrite(srv, con, key.ptr, key.len, val.ptr, val.len);
 710                         }
 711
 712                         lua_pop(L, 1);
 713                 }
 714         }
 715         lua_pop(L, 1); /* pop lighty.header */
 716
 717         return 0;
 718 }
 719
 720 /**
 721  * walk through the content array
 722  *
 723  * content = { "<pre>", { file = "/content" } , "</pre>" }
 724  *
 725  * header["Content-Type"] = "text/html"
 726  *
 727  * return 200
 728  */
 729 static int magnet_attach_content(server *srv, connection *con, lua_State *L, int lighty_table_ndx) {
 730         force_assert(lua_istable(L, lighty_table_ndx));
 731
 732         lua_getfield(L, lighty_table_ndx, "content"); /* lighty.content */
 733         if (lua_istable(L, -1)) {
 734                 int i;
 735                 /* content is found, and is a table */
 736
 737                 for (i = 1; ; i++) {
 738                         lua_rawgeti(L, -1, i);
 739
 740                         /* -1 is the value and should be the value ... aka a table */
 741                         if (lua_isstring(L, -1)) {
 742                                 const_buffer data = magnet_checkconstbuffer(L, -1);
 743
 744                                 chunkqueue_append_mem(con->write_queue, data.ptr, data.len);
 745                         } else if (lua_istable(L, -1)) {
 746                                 lua_getfield(L, -1, "filename");
 747                                 lua_getfield(L, -2, "length"); /* (0-based) end of range (not actually "length") */
 748                                 lua_getfield(L, -3, "offset"); /* (0-based) start of range */
 749
 750                                 if (lua_isstring(L, -3)) { /* filename has to be a string */
 751                                         buffer *fn = magnet_checkbuffer(L, -3);
 752                                         off_t off = (off_t) luaL_optinteger(L, -1, 0);
 753                                         off_t len = (off_t) luaL_optinteger(L, -2, -1); /*(-1 to http_chunk_append_file_range() uses file size minus offset)*/
 754                                         if (off < 0) {
 755                                                 buffer_free(fn);
 756                                                 return luaL_error(L, "offset for '%s' is negative", lua_tostring(L, -3));
 757                                         }
 758
 759                                         if (len >= off) {
 760                                                 len -= off;
 761                                         } else if (-1 != len) {
 762                                                 buffer_free(fn);
 763                                                 return luaL_error(L, "offset > length for '%s'", lua_tostring(L, -3));
 764                                         }
 765
 766                                         if (0 != len && 0 != http_chunk_append_file_range(srv, con, fn, off, len)) {
 767                                                 buffer_free(fn);
 768                                                 return luaL_error(L, "error opening file content '%s' at offset %lld", lua_tostring(L, -3), (long long)off);
 769                                         }
 770
 771                                         buffer_free(fn);
 772                                 } else {
 773                                         return luaL_error(L, "content[%d] is a table and requires the field \"filename\"", i);
 774                                 }
 775
 776                                 lua_pop(L, 3);
 777                         } else if (lua_isnil(L, -1)) {
 778                                 /* end of list */
 779
 780                                 lua_pop(L, 1);
 781
 782                                 break;
 783                         } else {
 784                                 return luaL_error(L, "content[%d] is neither a string nor a table: ", i);
 785                         }
 786
 787                         lua_pop(L, 1); /* pop the content[...] entry value */
 788                 }
 789         } else {
 790                 return luaL_error(L, "lighty.content has to be a table");
 791         }
 792         lua_pop(L, 1); /* pop lighty.content */
 793
 794         return 0;
 795 }
 796
 797 static int traceback(lua_State *L) {
 798         if (!lua_isstring(L, 1))  /* 'message' not a string? */
 799                 return 1;  /* keep it intact */
 800         lua_getglobal(L, "debug");
 801         if (!lua_istable(L, -1)) {
 802                 lua_pop(L, 1);
 803                 return 1;
 804         }
 805         lua_getfield(L, -1, "traceback");
 806         if (!lua_isfunction(L, -1)) {
 807                 lua_pop(L, 2);
 808                 return 1;
 809         }
 810         lua_pushvalue(L, 1);  /* pass error message */
 811         lua_pushinteger(L, 2);  /* skip this function and traceback */
 812         lua_call(L, 2, 1);  /* call debug.traceback */
 813         return 1;
 814 }
 815
 816 /* push traceback function before calling lua_pcall after narg arguments
 817  * have been pushed (inserts it before the arguments). returns index for
 818  * traceback function ("msgh" in lua_pcall)
 819  */
 820 static int push_traceback(lua_State *L, int narg) {
 821         int base = lua_gettop(L) - narg;  /* function index */
 822         lua_pushcfunction(L, traceback);
 823         lua_insert(L, base);
 824         return base;
 825 }
 826
 827 static handler_t magnet_attract(server *srv, connection *con, plugin_data *p, buffer *name) {
 828         lua_State *L;
 829         int lua_return_value;
 830         const int func_ndx = 1;
 831         const int lighty_table_ndx = 2;
 832
 833         /* get the script-context */
 834         L = script_cache_get_script(srv, con, p->cache, name);
 835
 836         if (lua_isstring(L, -1)) {
 837                 log_error_write(srv, __FILE__, __LINE__,
 838                                 "sbss",
 839                                 "loading script",
 840                                 name,
 841                                 "failed:",
 842                                 lua_tostring(L, -1));
 843
 844                 lua_pop(L, 1);
 845
 846                 force_assert(lua_gettop(L) == 0); /* only the error should have been on the stack */
 847
 848                 con->http_status = 500;
 849                 con->mode = DIRECT;
 850
 851                 return HANDLER_FINISHED;
 852         }
 853
 854         force_assert(lua_gettop(L) == 1);
 855         force_assert(lua_isfunction(L, func_ndx));
 856
 857         lua_pushlightuserdata(L, srv);
 858         lua_setfield(L, LUA_REGISTRYINDEX, LUA_RIDX_LIGHTTPD_SERVER);
 859
 860         lua_pushlightuserdata(L, con);
 861         lua_setfield(L, LUA_REGISTRYINDEX, LUA_RIDX_LIGHTTPD_CONNECTION);
 862
 863         lua_atpanic(L, magnet_atpanic);
 864
 865         /**
 866          * we want to create empty environment for our script
 867          *
 868          * setmetatable({}, {__index = _G})
 869          *
 870          * if a function symbol is not defined in our env, __index will lookup
 871          * in the global env.
 872          *
 873          * all variables created in the script-env will be thrown
 874          * away at the end of the script run.
 875          */
 876         lua_newtable(L); /* my empty environment aka {}              (sp += 1) */
 877
 878         /* we have to overwrite the print function */
 879         lua_pushcfunction(L, magnet_print);                       /* (sp += 1) */
 880         lua_setfield(L, -2, "print"); /* -1 is the env we want to set(sp -= 1) */
 881
 882         /**
 883          * lighty.request[] (ro) has the HTTP-request headers
 884          * lighty.env[] (rw) has various url/physical file paths and
 885          *                   request meta data; might contain nil values
 886          * lighty.req_env[] (ro) has the cgi environment
 887          * lighty.status[] (ro) has the status counters
 888          * lighty.content[] (rw) is a table of string/file
 889          * lighty.header[] (rw) is a array to set response headers
 890          */
 891
 892         lua_newtable(L); /* lighty.*                                 (sp += 1) */
 893
 894         lua_newtable(L); /*  {}                                      (sp += 1) */
 895         lua_newtable(L); /* the meta-table for the request-table     (sp += 1) */
 896         lua_pushcfunction(L, magnet_reqhdr_get);                  /* (sp += 1) */
 897         lua_setfield(L, -2, "__index");                           /* (sp -= 1) */
 898         lua_pushcfunction(L, magnet_reqhdr_pairs);                /* (sp += 1) */
 899         lua_setfield(L, -2, "__pairs");                           /* (sp -= 1) */
 900         lua_setmetatable(L, -2); /* tie the metatable to request     (sp -= 1) */
 901         lua_setfield(L, -2, "request"); /* content = {}              (sp -= 1) */
 902
 903         lua_newtable(L); /*  {}                                      (sp += 1) */
 904         lua_newtable(L); /* the meta-table for the env-table         (sp += 1) */
 905         lua_pushcfunction(L, magnet_env_get);                     /* (sp += 1) */
 906         lua_setfield(L, -2, "__index");                           /* (sp -= 1) */
 907         lua_pushcfunction(L, magnet_env_set);                     /* (sp += 1) */
 908         lua_setfield(L, -2, "__newindex");                        /* (sp -= 1) */
 909         lua_pushcfunction(L, magnet_env_pairs);                   /* (sp += 1) */
 910         lua_setfield(L, -2, "__pairs");                           /* (sp -= 1) */
 911         lua_setmetatable(L, -2); /* tie the metatable to env         (sp -= 1) */
 912         lua_setfield(L, -2, "env"); /* content = {}                  (sp -= 1) */
 913
 914         lua_newtable(L); /*  {}                                      (sp += 1) */
 915         lua_newtable(L); /* the meta-table for the req_env-table     (sp += 1) */
 916         lua_pushcfunction(L, magnet_cgi_get);                     /* (sp += 1) */
 917         lua_setfield(L, -2, "__index");                           /* (sp -= 1) */
 918         lua_pushcfunction(L, magnet_cgi_set);                     /* (sp += 1) */
 919         lua_setfield(L, -2, "__newindex");                        /* (sp -= 1) */
 920         lua_pushcfunction(L, magnet_cgi_pairs);                   /* (sp += 1) */
 921         lua_setfield(L, -2, "__pairs");                           /* (sp -= 1) */
 922         lua_setmetatable(L, -2); /* tie the metatable to req_env     (sp -= 1) */
 923         lua_setfield(L, -2, "req_env"); /* content = {}              (sp -= 1) */
 924
 925         lua_newtable(L); /*  {}                                      (sp += 1) */
 926         lua_newtable(L); /* the meta-table for the status-table      (sp += 1) */
 927         lua_pushcfunction(L, magnet_status_get);                  /* (sp += 1) */
 928         lua_setfield(L, -2, "__index");                           /* (sp -= 1) */
 929         lua_pushcfunction(L, magnet_status_set);                  /* (sp += 1) */
 930         lua_setfield(L, -2, "__newindex");                        /* (sp -= 1) */
 931         lua_pushcfunction(L, magnet_status_pairs);                /* (sp += 1) */
 932         lua_setfield(L, -2, "__pairs");                           /* (sp -= 1) */
 933         lua_setmetatable(L, -2); /* tie the metatable to statzs      (sp -= 1) */
 934         lua_setfield(L, -2, "status"); /* content = {}               (sp -= 1) */
 935
 936         /* add empty 'content' and 'header' tables */
 937         lua_newtable(L); /*  {}                                      (sp += 1) */
 938         lua_setfield(L, -2, "content"); /* content = {}              (sp -= 1) */
 939
 940         lua_newtable(L); /*  {}                                      (sp += 1) */
 941         lua_setfield(L, -2, "header"); /* header = {}                (sp -= 1) */
 942
 943         lua_pushinteger(L, MAGNET_RESTART_REQUEST);
 944         lua_setfield(L, -2, "RESTART_REQUEST");
 945
 946         lua_pushcfunction(L, magnet_stat);                        /* (sp += 1) */
 947         lua_setfield(L, -2, "stat"); /* -1 is the env we want to set (sp -= 1) */
 948
 949         /* insert lighty table at index 2 */
 950         lua_pushvalue(L, -1);
 951         lua_insert(L, lighty_table_ndx);
 952
 953         lua_setfield(L, -2, "lighty"); /* lighty.*                   (sp -= 1) */
 954
 955 #if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM < 502
 956         /* override the default pairs() function to our __pairs capable version;
 957          * not needed for lua 5.2+
 958          */
 959         lua_getglobal(L, "pairs"); /* push original pairs()          (sp += 1) */
 960         lua_pushcclosure(L, magnet_pairs, 1);
 961         lua_setfield(L, -2, "pairs");                             /* (sp -= 1) */
 962 #endif
 963
 964         lua_newtable(L); /* the meta-table for the new env           (sp += 1) */
 965         lua_pushglobaltable(L);                                   /* (sp += 1) */
 966         lua_setfield(L, -2, "__index"); /* { __index = _G }          (sp -= 1) */
 967         lua_setmetatable(L, -2); /* setmetatable({}, {__index = _G}) (sp -= 1) */
 968
 969         magnet_setfenv_mainfn(L, 1);                              /* (sp -= 1) */
 970
 971         /* pcall will destroy the func value, duplicate it */     /* (sp += 1) */
 972         lua_pushvalue(L, func_ndx);
 973         {
 974                 int errfunc = push_traceback(L, 0);
 975                 int ret = lua_pcall(L, 0, 1, errfunc);
 976                 lua_remove(L, errfunc);
 977
 978                 /* reset environment */
 979                 lua_pushglobaltable(L);                               /* (sp += 1) */
 980                 magnet_setfenv_mainfn(L, 1);                          /* (sp -= 1) */
 981
 982                 if (0 != ret) {
 983                         log_error_write(srv, __FILE__, __LINE__,
 984                                 "ss",
 985                                 "lua_pcall():",
 986                                 lua_tostring(L, -1));
 987                         lua_pop(L, 2); /* remove the error-msg and the lighty table at index 2 */
 988
 989                         force_assert(lua_gettop(L) == 1); /* only the function should be on the stack */
 990
 991                         con->http_status = 500;
 992                         con->mode = DIRECT;
 993
 994                         return HANDLER_FINISHED;
 995                 }
 996         }
 997
 998         /* we should have the function, the lighty table and the return value on the stack */
 999         force_assert(lua_gettop(L) == 3);
1000
1001         lua_return_value = (int) luaL_optinteger(L, -1, -1);
1002         lua_pop(L, 1); /* pop return value */
1003
1004         magnet_copy_response_header(srv, con, L, lighty_table_ndx);
1005
1006         {
1007                 handler_t result = HANDLER_GO_ON;
1008
1009                 if (lua_return_value > 99) {
1010                         con->http_status = lua_return_value;
1011                         con->file_finished = 1;
1012
1013                         /* try { ...*/
1014                         if (0 == setjmp(exceptionjmp)) {
1015                                 magnet_attach_content(srv, con, L, lighty_table_ndx);
1016                                 if (!chunkqueue_is_empty(con->write_queue)) {
1017                                         con->mode = p->id;
1018                                 }
1019                         } else {
1020                                 lua_settop(L, 2); /* remove all but function and lighty table */
1021                                 /* } catch () { */
1022                                 con->http_status = 500;
1023                                 con->mode = DIRECT;
1024                         }
1025
1026                         result = HANDLER_FINISHED;
1027                 } else if (MAGNET_RESTART_REQUEST == lua_return_value) {
1028                         result = HANDLER_COMEBACK;
1029                 }
1030
1031                 lua_pop(L, 1); /* pop the lighty table */
1032                 force_assert(lua_gettop(L) == 1); /* only the function should remain on the stack */
1033
1034                 return result;
1035         }
1036 }
1037
1038 static handler_t magnet_attract_array(server *srv, connection *con, plugin_data *p, array *files) {
1039         size_t i;
1040         handler_t ret = HANDLER_GO_ON;
1041
1042         /* no filename set */
1043         if (files->used == 0) return HANDLER_GO_ON;
1044
1045         srv->request_env(srv, con);
1046
1047         /**
1048          * execute all files and jump out on the first !HANDLER_GO_ON
1049          */
1050         for (i = 0; i < files->used && ret == HANDLER_GO_ON; i++) {
1051                 data_string *ds = (data_string *)files->data[i];
1052
1053                 if (buffer_string_is_empty(ds->value)) continue;
1054
1055                 ret = magnet_attract(srv, con, p, ds->value);
1056         }
1057
1058         if (con->error_handler_saved_status) {
1059                 /* retrieve (possibly modified) REDIRECT_STATUS and store as number */
1060                 unsigned long x;
1061                 data_string * const ds = (data_string *)array_get_element(con->environment, "REDIRECT_STATUS");
1062                 if (ds && (x = strtoul(ds->value->ptr, NULL, 10)) < 1000)
1063                         /*(simplified validity check x < 1000)*/
1064                         con->error_handler_saved_status =
1065                           con->error_handler_saved_status > 0 ? (int)x : -(int)x;
1066         }
1067
1068         return ret;
1069 }
1070
1071 URIHANDLER_FUNC(mod_magnet_uri_handler) {
1072         plugin_data *p = p_d;
1073
1074         mod_magnet_patch_connection(srv, con, p);
1075
1076         return magnet_attract_array(srv, con, p, p->conf.url_raw);
1077 }
1078
1079 URIHANDLER_FUNC(mod_magnet_physical) {
1080         plugin_data *p = p_d;
1081
1082         mod_magnet_patch_connection(srv, con, p);
1083
1084         return magnet_attract_array(srv, con, p, p->conf.physical_path);
1085 }
1086
1087
1088 /* this function is called at dlopen() time and inits the callbacks */
1089
1090 int mod_magnet_plugin_init(plugin *p);
1091 int mod_magnet_plugin_init(plugin *p) {
1092         p->version     = LIGHTTPD_VERSION_ID;
1093         p->name        = buffer_init_string("magnet");
1094
1095         p->init        = mod_magnet_init;
1096         p->handle_uri_clean  = mod_magnet_uri_handler;
1097         p->handle_physical   = mod_magnet_physical;
1098         p->set_defaults  = mod_magnet_set_defaults;
1099         p->cleanup     = mod_magnet_free;
1100
1101         p->data        = NULL;
1102
1103         return 0;
1104 }