libs/nixio/src/process.c

   1 /*
   2  * nixio - Linux I/O library for lua
   3  *
   4  *   Copyright (C) 2009 Steven Barth <steven@midlink.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #include "nixio.h"
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <errno.h>
  23 #include <string.h>
  24 #include <sys/stat.h>
  25 #include <sys/types.h>
  26 #include <signal.h>
  27
  28 #define NIXIO_EXECVE    0x01
  29 #define NIXIO_EXECV             0x02
  30 #define NIXIO_EXECVP    0x03
  31
  32 int nixio__exec(lua_State *L, int m) {
  33         const char *path = luaL_checkstring(L, 1);
  34         const char *arg;
  35         int argn, i;
  36
  37         if (m == NIXIO_EXECVE) {
  38                 luaL_checktype(L, 2, LUA_TTABLE);
  39                 argn = lua_objlen(L, 2) + 1;
  40         } else {
  41                 argn = lua_gettop(L);
  42         }
  43
  44         char **args = lua_newuserdata(L, sizeof(char*) * (argn + 1));
  45         args[argn] = NULL;
  46         args[0] = (char *)path;
  47
  48         if (m == NIXIO_EXECVE) {
  49                 for (i = 1; i < argn; i++) {
  50                         lua_rawgeti(L, 2, i);
  51                         arg = lua_tostring(L, -1);
  52                         luaL_argcheck(L, arg, 2, "invalid argument");
  53                         args[i] = (char *)arg;
  54                 }
  55
  56                 if (lua_isnoneornil(L, 3)) {
  57                         execv(path, args);
  58                 } else {
  59                         luaL_checktype(L, 3, LUA_TTABLE);
  60                         argn = 0;
  61                         lua_pushnil(L);
  62                         while (lua_next(L, 3)) {
  63                                 if (!lua_checkstack(L, 1)) {
  64                                         lua_settop(L, 0);
  65                                         return luaL_error(L, "stack overflow");
  66                                 }
  67
  68                                 if (!lua_type(L, -2) != LUA_TSTRING || !lua_isstring(L, -1)) {
  69                                         return luaL_argerror(L, 3, "invalid environment");
  70                                 }
  71
  72                                 lua_pushfstring(L, "%s=%s",
  73                                                 lua_tostring(L, -2), lua_tostring(L, -1));
  74
  75                                 lua_insert(L, 4);
  76                                 lua_pop(L, 1);
  77                                 argn++;
  78                         }
  79
  80                         char **env = lua_newuserdata(L, sizeof(char*) * (argn + 1));
  81                         env[argn] = NULL;
  82
  83                         for (i = 1; i < argn; i++) {
  84                                 env[i-1] = (char *)lua_tostring(L, -i);
  85                         }
  86
  87                         execve(path, args, env);
  88                 }
  89         } else {
  90                 for (i = 2; i <= argn; i++) {
  91                         arg = luaL_checkstring(L, i);
  92                         args[i-1] = (char *)arg;
  93                 }
  94
  95                 if (m == NIXIO_EXECV) {
  96                         execv(path, args);
  97                 } else {
  98                         execvp(path, args);
  99                 }
 100         }
 101
 102         return nixio__perror(L);
 103 }
 104
 105 #ifndef __WINNT__
 106 #include <sys/utsname.h>
 107 #include <sys/times.h>
 108 #include <sys/wait.h>
 109 #include <pwd.h>
 110 #include <grp.h>
 111
 112 static int nixio_fork(lua_State *L) {
 113         pid_t pid = fork();
 114         if (pid == -1) {
 115                 return nixio__perror(L);
 116         } else {
 117                 lua_pushinteger(L, pid);
 118                 return 1;
 119         }
 120 }
 121
 122 static int nixio_kill(lua_State *L) {
 123         return nixio__pstatus(L, !kill(luaL_checkint(L, 1), luaL_checkint(L, 2)));
 124 }
 125
 126 static int nixio_getppid(lua_State *L) {
 127         lua_pushinteger(L, getppid());
 128         return 1;
 129 }
 130
 131 static int nixio_getuid(lua_State *L) {
 132         lua_pushinteger(L, getuid());
 133         return 1;
 134 }
 135
 136 static int nixio_getgid(lua_State *L) {
 137         lua_pushinteger(L, getgid());
 138         return 1;
 139 }
 140
 141 static int nixio_setgid(lua_State *L) {
 142         return nixio__pstatus(L, !setgid(nixio__check_group(L, 1)));
 143 }
 144
 145 static int nixio_setuid(lua_State *L) {
 146         return nixio__pstatus(L, !setuid(nixio__check_user(L, 1)));
 147 }
 148
 149 static int nixio_nice(lua_State *L) {
 150         int nval = luaL_checkint(L, 1);
 151
 152         errno = 0;
 153         nval = nice(nval);
 154
 155         if (nval == -1 && errno) {
 156                 return nixio__perror(L);
 157         } else {
 158                 lua_pushinteger(L, nval);
 159                 return 1;
 160         }
 161 }
 162
 163 static int nixio_setsid(lua_State *L) {
 164         pid_t pid = setsid();
 165
 166         if (pid == -1) {
 167                 return nixio__perror(L);
 168         } else {
 169                 lua_pushinteger(L, pid);
 170                 return 1;
 171         }
 172 }
 173
 174 static int nixio_wait(lua_State *L) {
 175         pid_t pidin = luaL_optinteger(L, 1, -1), pidout;
 176         int options = 0, status;
 177
 178         const int j = lua_gettop(L);
 179         for (int i=2; i<=j; i++) {
 180                 const char *flag = luaL_checkstring(L, i);
 181                 if (!strcmp(flag, "nohang")) {
 182                         options |= WNOHANG;
 183                 } else if (!strcmp(flag, "untraced")) {
 184                         options |= WUNTRACED;
 185                 } else if (!strcmp(flag, "continued")) {
 186                         options |= WCONTINUED;
 187                 } else {
 188                         return luaL_argerror(L, i,
 189                                         "supported values: nohang, untraced, continued");
 190                 }
 191         }
 192
 193         do {
 194                 pidout = waitpid(pidin, &status, options);
 195         } while (pidout == -1 && errno == EINTR);
 196
 197         if (pidout == 0) {
 198                 lua_pushboolean(L, 0);
 199                 return 1;
 200         } else if (pidout == -1) {
 201                 return nixio__perror(L);
 202         } else {
 203                 lua_pushinteger(L, pidout);
 204         }
 205
 206         if (WIFEXITED(status)) {
 207                 lua_pushliteral(L, "exited");
 208                 lua_pushinteger(L, WEXITSTATUS(status));
 209     } else if (WIFSIGNALED(status)) {
 210         lua_pushliteral(L, "signaled");
 211         lua_pushinteger(L, WTERMSIG(status));
 212     } else if (WIFSTOPPED(status)) {
 213         lua_pushliteral(L, "stopped");
 214         lua_pushinteger(L, WSTOPSIG(status));
 215     } else {
 216         return 1;
 217     }
 218
 219     return 3;
 220 }
 221
 222 static int nixio_times(lua_State *L) {
 223         struct tms buf;
 224         if (times(&buf) == -1) {
 225                 return nixio__perror(L);
 226         } else {
 227                 lua_createtable(L, 0, 4);
 228                 lua_pushnumber(L, buf.tms_cstime);
 229                 lua_setfield(L, -2, "cstime");
 230
 231                 lua_pushnumber(L, buf.tms_cutime);
 232                 lua_setfield(L, -2, "cutime");
 233
 234                 lua_pushnumber(L, buf.tms_stime);
 235                 lua_setfield(L, -2, "stime");
 236
 237                 lua_pushnumber(L, buf.tms_utime);
 238                 lua_setfield(L, -2, "utime");
 239
 240                 return 1;
 241         }
 242 }
 243
 244 static int nixio_uname(lua_State *L) {
 245         struct utsname buf;
 246         if (uname(&buf)) {
 247                 return nixio__perror(L);
 248         }
 249
 250         lua_createtable(L, 0, 5);
 251
 252         lua_pushstring(L, buf.machine);
 253         lua_setfield(L, -2, "machine");
 254
 255         lua_pushstring(L, buf.version);
 256         lua_setfield(L, -2, "version");
 257
 258         lua_pushstring(L, buf.release);
 259         lua_setfield(L, -2, "release");
 260
 261         lua_pushstring(L, buf.nodename);
 262         lua_setfield(L, -2, "nodename");
 263
 264         lua_pushstring(L, buf.sysname);
 265         lua_setfield(L, -2, "sysname");
 266
 267         return 1;
 268 }
 269
 270 #endif /* !__WINNT__ */
 271
 272 static int nixio_chdir(lua_State *L) {
 273         return nixio__pstatus(L, !chdir(luaL_checkstring(L, 1)));
 274 }
 275
 276 static int nixio_signal(lua_State *L) {
 277         int sig = luaL_checkinteger(L, 1);
 278         const char *val = luaL_checkstring(L, 2);
 279
 280         if (!strcmp(val, "ign") || !strcmp(val, "ignore")) {
 281                 return nixio__pstatus(L, signal(sig, SIG_IGN) != SIG_ERR);
 282         } else if (!strcmp(val, "dfl") || !strcmp(val, "default")) {
 283                 return nixio__pstatus(L, signal(sig, SIG_DFL) != SIG_ERR);
 284         } else {
 285                 return luaL_argerror(L, 2, "supported values: ign, dfl");
 286         }
 287 }
 288
 289 static int nixio_getpid(lua_State *L) {
 290         lua_pushinteger(L, getpid());
 291         return 1;
 292 }
 293
 294 static int nixio_getenv(lua_State *L) {
 295         const char *key = luaL_optstring(L, 1, NULL);
 296         if (key) {
 297                 const char *val = getenv(key);
 298                 if (val) {
 299                         lua_pushstring(L, val);
 300                 } else {
 301                         lua_pushnil(L);
 302                 }
 303         } else {
 304                 lua_newtable(L);
 305                 extern char **environ;
 306                 for (char **c = environ; *c; c++) {
 307                         const char *delim = strchr(*c, '=');
 308                         if (!delim) {
 309                                 return luaL_error(L, "invalid environment");
 310                         }
 311                         lua_pushlstring(L, *c, delim-*c);
 312                         lua_pushstring(L, delim + 1);
 313                         lua_rawset(L, -3);
 314                 }
 315         }
 316         return 1;
 317 }
 318
 319 static int nixio_setenv(lua_State *L) {
 320         const char *key = luaL_checkstring(L, 1);
 321         const char *val = luaL_optstring(L, 2, NULL);
 322         return nixio__pstatus(L, (val) ? !setenv(key, val, 1) : !unsetenv(key));
 323 }
 324
 325 static int nixio_exec(lua_State *L) {
 326         return nixio__exec(L, NIXIO_EXECV);
 327 }
 328
 329 static int nixio_execp(lua_State *L) {
 330         return nixio__exec(L, NIXIO_EXECVP);
 331 }
 332
 333 static int nixio_exece(lua_State *L) {
 334         return nixio__exec(L, NIXIO_EXECVE);
 335 }
 336
 337 static int nixio_getcwd(lua_State *L) {
 338         char path[PATH_MAX];
 339
 340         if (getcwd(path, sizeof(path))) {
 341                 lua_pushstring(L, path);
 342                 return 1;
 343         } else {
 344                 return nixio__perror(L);
 345         }
 346 }
 347
 348 static int nixio_umask(lua_State *L) {
 349         char mask[9];
 350         lua_pushinteger(L,
 351                         nixio__mode_write(umask(nixio__check_mode(L, 1, -1)), mask));
 352         lua_pushlstring(L, mask, 9);
 353         return 2;
 354 }
 355
 356 #ifdef __linux__
 357
 358 #include <sys/sysinfo.h>
 359
 360 static int nixio_sysinfo(lua_State *L) {
 361         struct sysinfo info;
 362         if (sysinfo(&info)) {
 363                 return nixio__perror(L);
 364         }
 365
 366         lua_createtable(L, 0, 12);
 367
 368         lua_pushnumber(L, info.bufferram);
 369         lua_setfield(L, -2, "bufferram");
 370
 371         lua_pushnumber(L, info.freehigh);
 372         lua_setfield(L, -2, "freehigh");
 373
 374         lua_pushnumber(L, info.freeram);
 375         lua_setfield(L, -2, "freeram");
 376
 377         lua_pushnumber(L, info.freeswap);
 378         lua_setfield(L, -2, "freeswap");
 379
 380         lua_createtable(L, 0, 3);
 381         for (int i=0; i<3; i++) {
 382                 lua_pushnumber(L, info.loads[i] / 65536.);
 383                 lua_rawseti(L, -2, i+1);
 384         }
 385         lua_setfield(L, -2, "loads");
 386
 387         lua_pushnumber(L, info.mem_unit);
 388         lua_setfield(L, -2, "mem_unit");
 389
 390         lua_pushnumber(L, info.procs);
 391         lua_setfield(L, -2, "procs");
 392
 393         lua_pushnumber(L, info.sharedram);
 394         lua_setfield(L, -2, "sharedram");
 395
 396         lua_pushnumber(L, info.totalhigh);
 397         lua_setfield(L, -2, "totalhigh");
 398
 399         lua_pushnumber(L, info.totalram);
 400         lua_setfield(L, -2, "totalram");
 401
 402         lua_pushnumber(L, info.totalswap);
 403         lua_setfield(L, -2, "totalswap");
 404
 405         lua_pushnumber(L, info.uptime);
 406         lua_setfield(L, -2, "uptime");
 407
 408         return 1;
 409 }
 410
 411 #endif
 412
 413
 414 /* module table */
 415 static const luaL_reg R[] = {
 416 #ifdef __linux__
 417         {"sysinfo",             nixio_sysinfo},
 418 #endif
 419 #ifndef __WINNT__
 420         {"fork",                nixio_fork},
 421         {"kill",                nixio_kill},
 422         {"nice",                nixio_nice},
 423         {"getppid",             nixio_getppid},
 424         {"getuid",              nixio_getuid},
 425         {"getgid",              nixio_getgid},
 426         {"setuid",              nixio_setuid},
 427         {"setgid",              nixio_setgid},
 428         {"setsid",              nixio_setsid},
 429         {"wait",                nixio_wait},
 430         {"waitpid",             nixio_wait},
 431         {"times",               nixio_times},
 432         {"uname",               nixio_uname},
 433 #endif
 434         {"chdir",               nixio_chdir},
 435         {"signal",              nixio_signal},
 436         {"getpid",              nixio_getpid},
 437         {"getenv",              nixio_getenv},
 438         {"setenv",              nixio_setenv},
 439         {"putenv",              nixio_setenv},
 440         {"exec",                nixio_exec},
 441         {"execp",               nixio_execp},
 442         {"exece",               nixio_exece},
 443         {"getcwd",              nixio_getcwd},
 444         {"umask",               nixio_umask},
 445         {NULL,                  NULL}
 446 };
 447
 448 void nixio_open_process(lua_State *L) {
 449         luaL_register(L, NULL, R);
 450 }