clients/lib/iolib.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <time.h>
   4 #include <stdlib.h>
   5 #include <errno.h>
   6
   7 #include "lua.h"
   8 #include "auxlib.h"
   9 #include "luadebug.h"
  10 #include "lualib.h"
  11
  12
  13 int lua_tagio;
  14
  15
  16 #ifdef POPEN
  17 FILE *popen();
  18 int pclose();
  19 #else
  20 #define popen(x,y) NULL  /* that is, popen always fails */
  21 #define pclose(x)  (-1)
  22 #endif
  23
  24
  25 static void pushresult (int i)
  26 {
  27   if (i)
  28     lua_pushuserdata(NULL);
  29   else {
  30     lua_pushnil();
  31 #ifndef NOSTRERROR
  32     lua_pushstring(strerror(errno));
  33 #else
  34     lua_pushstring("O.S. unable to define the error");
  35 #endif
  36   }
  37 }
  38
  39
  40
  41 static FILE *getfile (char *name)
  42 {
  43   lua_Object f = lua_getglobal(name);
  44   if (!lua_isuserdata(f) || lua_tag(f) != lua_tagio)
  45     luaL_verror("global variable %s is not a file handle", name);
  46   return lua_getuserdata(f);
  47 }
  48
  49
  50 static void closefile (char *name)
  51 {
  52   FILE *f = getfile(name);
  53   if (f == stdin || f == stdout) return;
  54   if (pclose(f) == -1)
  55     fclose(f);
  56 }
  57
  58
  59 static void setfile (FILE *f, char *name)
  60 {
  61   lua_pushusertag(f, lua_tagio);
  62   lua_setglobal(name);
  63 }
  64
  65
  66 static void setreturn (FILE *f, char *name)
  67 {
  68   setfile(f, name);
  69   lua_pushusertag(f, lua_tagio);
  70 }
  71
  72
  73 static void io_readfrom (void)
  74 {
  75   FILE *current;
  76   lua_Object f = lua_getparam(1);
  77   if (f == LUA_NOOBJECT) {
  78     closefile("_INPUT");
  79     current = stdin;
  80   }
  81   else if (lua_tag(f) == lua_tagio)
  82     current = lua_getuserdata(f);
  83   else {
  84     char *s = luaL_check_string(1);
  85     current = (*s == '|') ? popen(s+1, "r") : fopen(s, "r");
  86     if (current == NULL) {
  87       pushresult(0);
  88       return;
  89     }
  90   }
  91   setreturn(current, "_INPUT");
  92 }
  93
  94
  95 static void io_writeto (void)
  96 {
  97   FILE *current;
  98   lua_Object f = lua_getparam(1);
  99   if (f == LUA_NOOBJECT) {
 100     closefile("_OUTPUT");
 101     current = stdout;
 102   }
 103   else if (lua_tag(f) == lua_tagio)
 104     current = lua_getuserdata(f);
 105   else {
 106     char *s = luaL_check_string(1);
 107     current = (*s == '|') ? popen(s+1,"w") : fopen(s,"w");
 108     if (current == NULL) {
 109       pushresult(0);
 110       return;
 111     }
 112   }
 113   setreturn(current, "_OUTPUT");
 114 }
 115
 116
 117 static void io_appendto (void)
 118 {
 119   char *s = luaL_check_string(1);
 120   FILE *fp = fopen (s, "a");
 121   if (fp != NULL)
 122     setreturn(fp, "_OUTPUT");
 123   else
 124     pushresult(0);
 125 }
 126
 127
 128 #define NEED_OTHER (EOF-1)  /* just some flag different from EOF */
 129
 130 static void io_read (void)
 131 {
 132   FILE *f = getfile("_INPUT");
 133   char *buff;
 134   char *p = luaL_opt_string(1, "[^\n]*{\n}");
 135   int inskip = 0;  /* to control {skips} */
 136   int c = NEED_OTHER;
 137   luaI_emptybuff();
 138   while (*p) {
 139     if (*p == '{') {
 140       inskip++;
 141       p++;
 142     }
 143     else if (*p == '}') {
 144       if (inskip == 0)
 145         lua_error("unbalanced braces in read pattern");
 146       inskip--;
 147       p++;
 148     }
 149     else {
 150       char *ep = luaL_item_end(p);  /* get what is next */
 151       int m;  /* match result */
 152       if (c == NEED_OTHER) c = getc(f);
 153       m = (c == EOF) ? 0 : luaL_singlematch((char)c, p);
 154       if (m) {
 155         if (inskip == 0) luaI_addchar(c);
 156         c = NEED_OTHER;
 157       }
 158       switch (*ep) {
 159         case '*':  /* repetition */
 160           if (!m) p = ep+1;  /* else stay in (repeat) the same item */
 161           break;
 162         case '?':  /* optional */
 163           p = ep+1;  /* continues reading the pattern */
 164           break;
 165         default:
 166           if (m) p = ep;  /* continues reading the pattern */
 167           else
 168             goto break_while;   /* pattern fails */
 169       }
 170     }
 171   } break_while:
 172   if (c >= 0)  /* not EOF nor NEED_OTHER? */
 173      ungetc(c, f);
 174   buff = luaI_addchar(0);
 175   if (*buff != 0 || *p == 0)  /* read something or did not fail? */
 176     lua_pushstring(buff);
 177 }
 178
 179
 180 static void io_write (void)
 181 {
 182   FILE *f = getfile("_OUTPUT");
 183   int arg = 1;
 184   int status = 1;
 185   char *s;
 186   while ((s = luaL_opt_string(arg++, NULL)) != NULL)
 187     status = status && (fputs(s, f) != EOF);
 188   pushresult(status);
 189 }
 190
 191
 192 static void io_execute (void)
 193 {
 194   lua_pushnumber(system(luaL_check_string(1)));
 195 }
 196
 197
 198 static void io_remove  (void)
 199 {
 200   pushresult(remove(luaL_check_string(1)) == 0);
 201 }
 202
 203
 204 static void io_rename (void)
 205 {
 206   pushresult(rename(luaL_check_string(1),
 207                     luaL_check_string(2)) == 0);
 208 }
 209
 210
 211 static void io_tmpname (void)
 212 {
 213   lua_pushstring(tmpnam(NULL));
 214 }
 215
 216
 217
 218 static void io_getenv (void)
 219 {
 220   lua_pushstring(getenv(luaL_check_string(1))); /* if NULL push nil */
 221 }
 222
 223
 224 static void io_date (void)
 225 {
 226   time_t t;
 227   struct tm *tm;
 228   char *s = luaL_opt_string(1, "%c");
 229   char b[BUFSIZ];
 230   time(&t); tm = localtime(&t);
 231   if (strftime(b,sizeof(b),s,tm))
 232     lua_pushstring(b);
 233   else
 234     lua_error("invalid `date' format");
 235 }
 236
 237
 238 static void io_exit (void)
 239 {
 240   lua_Object o = lua_getparam(1);
 241   exit(lua_isnumber(o) ? (int)lua_getnumber(o) : 1);
 242 }
 243
 244
 245 static void io_debug (void)
 246 {
 247   while (1) {
 248     char buffer[250];
 249     fprintf(stderr, "lua_debug> ");
 250     if (fgets(buffer, sizeof(buffer), stdin) == 0) return;
 251     if (strcmp(buffer, "cont\n") == 0) return;
 252     lua_dostring(buffer);
 253   }
 254 }
 255
 256
 257 static void lua_printstack (FILE *f)
 258 {
 259   int level = 1;  /* skip level 0 (it's this function) */
 260   lua_Object func;
 261   while ((func = lua_stackedfunction(level++)) != LUA_NOOBJECT) {
 262     char *name;
 263     int currentline;
 264     char *filename;
 265     int linedefined;
 266     lua_funcinfo(func, &filename, &linedefined);
 267     fprintf(f, (level==2) ? "Active Stack:\n\t" : "\t");
 268     switch (*lua_getobjname(func, &name)) {
 269       case 'g':
 270         fprintf(f, "function %s", name);
 271         break;
 272       case 't':
 273         fprintf(f, "`%s' tag method", name);
 274         break;
 275       default: {
 276         if (linedefined == 0)
 277           fprintf(f, "main of %s", filename);
 278         else if (linedefined < 0)
 279           fprintf(f, "%s", filename);
 280         else
 281           fprintf(f, "function (%s:%d)", filename, linedefined);
 282         filename = NULL;
 283       }
 284     }
 285     if ((currentline = lua_currentline(func)) > 0)
 286       fprintf(f, " at line %d", currentline);
 287     if (filename)
 288       fprintf(f, " [in file %s]", filename);
 289     fprintf(f, "\n");
 290   }
 291 }
 292
 293
 294 static void errorfb (void)
 295 {
 296   fprintf(stderr, "lua: %s\n", lua_getstring(lua_getparam(1)));
 297   lua_printstack(stderr);
 298 }
 299
 300
 301
 302 static struct luaL_reg iolib[] = {
 303 {"readfrom", io_readfrom},
 304 {"writeto",  io_writeto},
 305 {"appendto", io_appendto},
 306 {"read",     io_read},
 307 {"write",    io_write},
 308 {"execute",  io_execute},
 309 {"remove",   io_remove},
 310 {"rename",   io_rename},
 311 {"tmpname",   io_tmpname},
 312 {"getenv",   io_getenv},
 313 {"date",     io_date},
 314 {"exit",     io_exit},
 315 {"debug",    io_debug},
 316 {"print_stack", errorfb}
 317 };
 318
 319 void iolib_open (void)
 320 {
 321   lua_tagio = lua_newtag();
 322   setfile(stdin, "_INPUT");
 323   setfile(stdout, "_OUTPUT");
 324   setfile(stdin, "_STDIN");
 325   setfile(stdout, "_STDOUT");
 326   setfile(stderr, "_STDERR");
 327   luaL_openlib(iolib, (sizeof(iolib)/sizeof(iolib[0])));
 328   lua_pushcfunction(errorfb);
 329   lua_seterrormethod();
 330 }