1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libraries/extos/extos.c	Sun Oct 25 12:00:00 2009 +0100
     1.3 @@ -0,0 +1,351 @@
     1.4 +#include <lua.h>
     1.5 +#include <lauxlib.h>
     1.6 +#include <dirent.h>
     1.7 +#include <time.h>
     1.8 +#include <unistd.h>
     1.9 +#include <sys/types.h>
    1.10 +#include <sys/wait.h>
    1.11 +#include <signal.h>
    1.12 +#include <errno.h>
    1.13 +#include <stdio.h>
    1.14 +#include <string.h>
    1.15 +#include <fcntl.h>
    1.16 +#include <poll.h>
    1.17 +#include <stdlib.h>
    1.18 +
    1.19 +#define EXTOS_MAX_ERRLEN 80
    1.20 +#define EXTOS_EXEC_MAX_ARGS 64
    1.21 +
    1.22 +static lua_Number extos_monotonic_start_time;
    1.23 +
    1.24 +static int extos_pfilter(lua_State *L) {
    1.25 +  int i, result, exit_status, status_pipe_len;
    1.26 +  const char *in_buf;
    1.27 +  size_t in_len;
    1.28 +  size_t in_pos = 0;
    1.29 +  const char *filename;
    1.30 +  const char *args[EXTOS_EXEC_MAX_ARGS+2];
    1.31 +  int pipe_status[2];
    1.32 +  int pipe_in[2];
    1.33 +  int pipe_out[2];
    1.34 +  int pipe_err[2];
    1.35 +  pid_t child;
    1.36 +  char status_buf[1];
    1.37 +  char *out_buf = NULL;
    1.38 +  size_t out_len = 1024;
    1.39 +  size_t out_pos = 0;
    1.40 +  char *err_buf = NULL;
    1.41 +  size_t err_len = 1024;
    1.42 +  size_t err_pos = 0;
    1.43 +  void *old_sigpipe_action;
    1.44 +  struct pollfd fds[3];
    1.45 +  int in_closed = 0;
    1.46 +  int out_closed = 0;
    1.47 +  int err_closed = 0;
    1.48 +  void *newptr;
    1.49 +  char errmsg[EXTOS_MAX_ERRLEN+1];
    1.50 +  in_buf = luaL_optlstring(L, 1, "", &in_len);
    1.51 +  filename = luaL_checkstring(L, 2);
    1.52 +  args[0] = filename;
    1.53 +  for (i = 0; i < EXTOS_EXEC_MAX_ARGS; i++) {
    1.54 +    if (lua_isnoneornil(L, 3+i)) break;
    1.55 +    else args[i+1] = luaL_checkstring(L, 3+i);
    1.56 +  }
    1.57 +  if (!lua_isnoneornil(L, 3+i)) {
    1.58 +    return luaL_error(L, "Too many arguments for pfilter call.");
    1.59 +  }
    1.60 +  args[i+1] = 0;
    1.61 +  // status pipe for internal communication
    1.62 +  if (pipe(pipe_status) < 0) {
    1.63 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.64 +    goto extos_pfilter_error_A0;
    1.65 +  }
    1.66 +  // stdin
    1.67 +  if (pipe(pipe_in) < 0) {
    1.68 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.69 +    goto extos_pfilter_error_A1;
    1.70 +  }
    1.71 +  if (in_len) {
    1.72 +    do result = fcntl(pipe_in[1], F_SETFL, O_NONBLOCK); while (result < 0 && errno == EINTR);
    1.73 +  } else {
    1.74 +    do result = close(pipe_in[1]); while (result < 0 && errno == EINTR);
    1.75 +    in_closed = 1;
    1.76 +  }
    1.77 +  if (result < 0) {
    1.78 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.79 +    goto extos_pfilter_error_A2;
    1.80 +  }
    1.81 +  // stdout
    1.82 +  if (pipe(pipe_out) < 0) {
    1.83 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.84 +    goto extos_pfilter_error_A2;
    1.85 +  }
    1.86 +  do result = fcntl(pipe_out[0], F_SETFL, O_NONBLOCK); while (result < 0 && errno == EINTR);
    1.87 +  if (result < 0) {
    1.88 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.89 +    goto extos_pfilter_error_A3;
    1.90 +  }
    1.91 +  // stderr
    1.92 +  if (pipe(pipe_err) < 0) {
    1.93 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.94 +    goto extos_pfilter_error_A3;
    1.95 +  }
    1.96 +  do result = fcntl(pipe_err[0], F_SETFL, O_NONBLOCK); while (result < 0 && errno == EINTR);
    1.97 +  if (result < 0) {
    1.98 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
    1.99 +    goto extos_pfilter_error_A4;
   1.100 +  }
   1.101 +  // fork
   1.102 +  child = fork();
   1.103 +  if (child < 0) {
   1.104 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
   1.105 +    goto extos_pfilter_error_A4;
   1.106 +  }
   1.107 +  // skip error handling
   1.108 +  goto extos_pfilter_success_A;
   1.109 +  // error handling
   1.110 +  extos_pfilter_error_A4:
   1.111 +  do result = close(pipe_err[0]); while (result < 0 && errno == EINTR);
   1.112 +  do result = close(pipe_err[1]); while (result < 0 && errno == EINTR);  
   1.113 +  extos_pfilter_error_A3:
   1.114 +  do result = close(pipe_out[0]); while (result < 0 && errno == EINTR);
   1.115 +  do result = close(pipe_out[1]); while (result < 0 && errno == EINTR);  
   1.116 +  extos_pfilter_error_A2:
   1.117 +  do result = close(pipe_in[0]); while (result < 0 && errno == EINTR);
   1.118 +  do result = close(pipe_in[1]); while (result < 0 && errno == EINTR);
   1.119 +  extos_pfilter_error_A1:
   1.120 +  do result = close(pipe_status[0]); while (result < 0 && errno == EINTR);
   1.121 +  do result = close(pipe_status[1]); while (result < 0 && errno == EINTR);  
   1.122 +  extos_pfilter_error_A0:
   1.123 +  return luaL_error(L, "Unexpected error in pfilter: %s", errmsg);
   1.124 +  // end of error handling
   1.125 +  extos_pfilter_success_A:
   1.126 +  if (child) {  // parent
   1.127 +    old_sigpipe_action = signal(SIGPIPE, SIG_IGN);
   1.128 +    do result = close(pipe_status[1]); while (result < 0 && errno == EINTR);
   1.129 +    if (result < 0) goto extos_pfilter_error_B;
   1.130 +    do result = close(pipe_in[0]); while (result < 0 && errno == EINTR);
   1.131 +    if (result < 0) goto extos_pfilter_error_B;
   1.132 +    do result = close(pipe_out[1]); while (result < 0 && errno == EINTR);
   1.133 +    if (result < 0) goto extos_pfilter_error_B;
   1.134 +    do result = close(pipe_err[1]); while (result < 0 && errno == EINTR);
   1.135 +    if (result < 0) goto extos_pfilter_error_B;
   1.136 +    out_buf = malloc(out_len * sizeof(char));
   1.137 +    if (!out_buf) goto extos_pfilter_error_B;
   1.138 +    err_buf = malloc(err_len * sizeof(char));
   1.139 +    if (!err_buf) goto extos_pfilter_error_B;
   1.140 +    while (!in_closed || !out_closed || !err_closed) {
   1.141 +      i = 0;
   1.142 +      if (!in_closed) {
   1.143 +        fds[i].fd = pipe_in[1];
   1.144 +        fds[i].events = POLLOUT;
   1.145 +        i++;
   1.146 +      }
   1.147 +      if (!out_closed) {
   1.148 +        fds[i].fd = pipe_out[0];
   1.149 +        fds[i].events = POLLIN;
   1.150 +        i++;
   1.151 +      }
   1.152 +      if (!err_closed) {
   1.153 +        fds[i].fd = pipe_err[0];
   1.154 +        fds[i].events = POLLIN;
   1.155 +        i++;
   1.156 +      }
   1.157 +      do result = poll(fds, i, -1); while (result < 0 && errno == EINTR);
   1.158 +      if (result < 0) goto extos_pfilter_error_B;
   1.159 +      if (!in_closed) {
   1.160 +        do result = write(pipe_in[1], in_buf+in_pos, in_len-in_pos); while (result < 0 && errno == EINTR);
   1.161 +        if (result < 0) {
   1.162 +          if (errno == EPIPE) {
   1.163 +            do result = close(pipe_in[1]); while (result < 0 && errno == EINTR);
   1.164 +            in_closed = 1;
   1.165 +          } else if (errno != EAGAIN) {
   1.166 +            goto extos_pfilter_error_B;
   1.167 +          }
   1.168 +        } else {
   1.169 +          in_pos += result;
   1.170 +          if (in_pos == in_len) {
   1.171 +            do result = close(pipe_in[1]); while (result < 0 && errno == EINTR);
   1.172 +            in_closed = 1;
   1.173 +          }
   1.174 +        }
   1.175 +      }
   1.176 +      if (!out_closed) {
   1.177 +        do result = read(pipe_out[0], out_buf+out_pos, out_len-out_pos); while (result < 0 && errno == EINTR);
   1.178 +        if (result < 0) {
   1.179 +          if (errno != EAGAIN) goto extos_pfilter_error_B;
   1.180 +        } else if (result == 0) {
   1.181 +          do result = close(pipe_out[0]); while (result < 0 && errno == EINTR);
   1.182 +          out_closed = 1;
   1.183 +        } else {
   1.184 +          out_pos += result;
   1.185 +          if (out_pos == out_len) {
   1.186 +            out_len *= 2;
   1.187 +            newptr = realloc(out_buf, out_len * sizeof(char));
   1.188 +            if (!newptr) goto extos_pfilter_error_B;
   1.189 +            out_buf = newptr;
   1.190 +          }
   1.191 +        }
   1.192 +      }
   1.193 +      if (!err_closed) {
   1.194 +        do result = read(pipe_err[0], err_buf+err_pos, err_len-err_pos); while (result < 0 && errno == EINTR);
   1.195 +        if (result < 0) {
   1.196 +          if (errno != EAGAIN) goto extos_pfilter_error_B;
   1.197 +        } else if (result == 0) {
   1.198 +          do result = close(pipe_err[0]); while (result < 0 && errno == EINTR);
   1.199 +          err_closed = 1;
   1.200 +        } else {
   1.201 +          err_pos += result;
   1.202 +          if (err_pos == err_len) {
   1.203 +            err_len *= 2;
   1.204 +            newptr = realloc(err_buf, err_len * sizeof(char));
   1.205 +            if (!newptr) goto extos_pfilter_error_B;
   1.206 +            err_buf = newptr;
   1.207 +          }
   1.208 +        }
   1.209 +      }
   1.210 +    }
   1.211 +    lua_pushlstring(L, out_buf, out_pos);
   1.212 +    free(out_buf);
   1.213 +    out_buf = NULL;
   1.214 +    lua_pushlstring(L, err_buf, err_pos);
   1.215 +    free(err_buf);
   1.216 +    err_buf = NULL;
   1.217 +    do result = waitpid(child, &exit_status, 0); while (result < 0 && errno == EINTR);
   1.218 +    child = 0;
   1.219 +    if (result < 0) goto extos_pfilter_error_B;
   1.220 +    do status_pipe_len = read(pipe_status[0], status_buf, 1); while (status_pipe_len < 0 && errno == EINTR);
   1.221 +    if (status_pipe_len < 0) goto extos_pfilter_error_B;
   1.222 +    do result = close(pipe_status[0]); while (result < 0 && errno == EINTR);
   1.223 +    signal(SIGPIPE, old_sigpipe_action);
   1.224 +    if (status_pipe_len == 0) {
   1.225 +      if (WIFEXITED(exit_status)) lua_pushinteger(L, WEXITSTATUS(exit_status));
   1.226 +      else lua_pushinteger(L, -WTERMSIG(exit_status));
   1.227 +      return 3;
   1.228 +    } else if (status_buf[0] == 0) {
   1.229 +      return luaL_error(L, "Error in pfilter while reopening standard file descriptors in child process.");
   1.230 +    } else {
   1.231 +      strerror_r(status_buf[0], errmsg, EXTOS_MAX_ERRLEN+1);
   1.232 +      lua_pushnil(L);
   1.233 +      lua_pushfstring(L, "Could not execute \"%s\": %s", filename, errmsg);
   1.234 +      return 2;
   1.235 +    }
   1.236 +    extos_pfilter_error_B:
   1.237 +    signal(SIGPIPE, old_sigpipe_action);
   1.238 +    strerror_r(errno, errmsg, EXTOS_MAX_ERRLEN+1);
   1.239 +    if (out_buf) free(out_buf);
   1.240 +    if (err_buf) free(err_buf);
   1.241 +    if (!in_closed) {
   1.242 +      do result = close(pipe_in[1]); while (result < 0 && errno == EINTR);
   1.243 +    }
   1.244 +    if (!out_closed) {
   1.245 +      do result = close(pipe_out[0]); while (result < 0 && errno == EINTR);
   1.246 +    }
   1.247 +    if (!err_closed) {
   1.248 +      do result = close(pipe_err[0]); while (result < 0 && errno == EINTR);
   1.249 +    }
   1.250 +    if (child) do result = waitpid(child, &exit_status, 0); while (result < 0 && errno == EINTR);
   1.251 +    return luaL_error(L, "Unexpected error in pfilter: %s", errmsg);
   1.252 +  } else {  // child
   1.253 +    do result = close(pipe_status[0]); while (result < 0 && errno == EINTR);
   1.254 +    do result = close(pipe_in[1]); while (result < 0 && errno == EINTR);
   1.255 +    do result = close(pipe_out[0]); while (result < 0 && errno == EINTR);
   1.256 +    do result = close(0); while (result < 0 && errno == EINTR);
   1.257 +    do result = close(1); while (result < 0 && errno == EINTR);
   1.258 +    do result = close(2); while (result < 0 && errno == EINTR);
   1.259 +    do result = dup(pipe_in[0]); while (result < 0 && errno == EINTR);
   1.260 +    if (result != 0) goto extos_pfilter_error_fd_remapping;
   1.261 +    do result = dup(pipe_out[1]); while (result < 0 && errno == EINTR);
   1.262 +    if (result != 1) goto extos_pfilter_error_fd_remapping;
   1.263 +    do result = dup(pipe_err[1]); while (result < 0 && errno == EINTR);
   1.264 +    if (result != 2) goto extos_pfilter_error_fd_remapping;
   1.265 +    execvp(filename, args);
   1.266 +    status_buf[0] = errno;
   1.267 +    do result = write(pipe_status[1], status_buf, 1); while (result < 0 && errno == EINTR);
   1.268 +    _exit(0);
   1.269 +    extos_pfilter_error_fd_remapping:
   1.270 +    status_buf[0] = 0;
   1.271 +    do result = write(pipe_status[1], status_buf, 1); while (result < 0 && errno == EINTR);
   1.272 +    _exit(0);
   1.273 +  }
   1.274 +}
   1.275 +
   1.276 +static int extos_listdir(lua_State *L) {
   1.277 +  DIR *dir;
   1.278 +  int i = 1;
   1.279 +  struct dirent entry_buffer;
   1.280 +  struct dirent *entry;
   1.281 +  dir = opendir(luaL_checkstring(L, 1));
   1.282 +  if (!dir) {
   1.283 +    lua_pushnil(L);
   1.284 +    lua_pushliteral(L, "Could not list directory.");
   1.285 +    return 2;
   1.286 +  }
   1.287 +  lua_settop(L, 0);
   1.288 +  lua_newtable(L);  // 1
   1.289 +  while (1) {
   1.290 +    readdir_r(dir, &entry_buffer, &entry);
   1.291 +    if (!entry) break;
   1.292 +    // Linux doesn't have d_namlen
   1.293 +    //lua_pushlstring(L, entry->d_name, entry->d_namlen);
   1.294 +    lua_pushstring(L, entry->d_name);
   1.295 +    lua_rawseti(L, 1, i++);
   1.296 +  }
   1.297 +  closedir(dir);
   1.298 +  return 1;
   1.299 +}
   1.300 +
   1.301 +static int extos_crypt(lua_State *L) {
   1.302 +  char *key;
   1.303 +  char *salt;
   1.304 +  char *result;
   1.305 +  key = luaL_checkstring(L, 1);
   1.306 +  salt = luaL_checkstring(L, 2);
   1.307 +  result = crypt(key, salt);  // TODO: Call not thread safe
   1.308 +  if (result) lua_pushstring(L, result);
   1.309 +  else lua_pushnil(L);
   1.310 +  return 1;
   1.311 +}
   1.312 +
   1.313 +static int extos_hires_time(lua_State *L) {
   1.314 +  struct timespec tp;
   1.315 +  if (clock_gettime(CLOCK_REALTIME, &tp)) {
   1.316 +    return luaL_error(L, "Could not access CLOCK_REALTIME.");
   1.317 +  }
   1.318 +  lua_pushnumber(L, tp.tv_sec + 0.000000001 * tp.tv_nsec);
   1.319 +  return 1;
   1.320 +}
   1.321 +
   1.322 +// returns time in seconds since loading the library
   1.323 +static int extos_monotonic_hires_time(lua_State *L) {
   1.324 +  struct timespec tp;
   1.325 +  if (clock_gettime(CLOCK_MONOTONIC, &tp)) {
   1.326 +    return luaL_error(L, "Could not access CLOCK_MONOTONIC.");
   1.327 +  }
   1.328 +  lua_pushnumber(L,
   1.329 +    tp.tv_sec + 0.000000001 * tp.tv_nsec - extos_monotonic_start_time
   1.330 +  );
   1.331 +  return 1;
   1.332 +}
   1.333 +
   1.334 +int luaopen_extos(lua_State *L) {
   1.335 +  {
   1.336 +    struct timespec tp;
   1.337 +    if (clock_gettime(CLOCK_MONOTONIC, &tp)) {
   1.338 +      return luaL_error(L, "Could not access monotonic hires time.");
   1.339 +    }
   1.340 +    extos_monotonic_start_time = tp.tv_sec + 0.000000001 * tp.tv_nsec;
   1.341 +  }
   1.342 +  lua_getglobal(L, "os");
   1.343 +  lua_pushcfunction(L, extos_pfilter);
   1.344 +  lua_setfield(L, -2, "pfilter");
   1.345 +  lua_pushcfunction(L, extos_listdir);
   1.346 +  lua_setfield(L, -2, "listdir");
   1.347 +  lua_pushcfunction(L, extos_crypt);
   1.348 +  lua_setfield(L, -2, "crypt");
   1.349 +  lua_pushcfunction(L, extos_hires_time);
   1.350 +  lua_setfield(L, -2, "hires_time");
   1.351 +  lua_pushcfunction(L, extos_monotonic_hires_time);
   1.352 +  lua_setfield(L, -2, "monotonic_hires_time");
   1.353 +  return 0;
   1.354 +}