src/lua/lua.c

   1 /*
   2 ** $Id: lua.c,v 1.21 1999/07/02 18:22:38 roberto Exp $
   3 ** Lua stand-alone interpreter
   4 ** See Copyright Notice in lua.h
   5 */
   6
   7
   8 #include <signal.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12
  13 #include "lua.h"
  14 #include "luadebug.h"
  15 #include "lualib.h"
  16
  17
  18 #ifdef _POSIX_SOURCE
  19 #include <unistd.h>
  20 #else
  21 #define isatty(x)       (x==0)  /* assume stdin is a tty */
  22 #endif
  23
  24
  25 typedef void (*handler)(int);  /* type for signal actions */
  26
  27 static void laction (int i);
  28
  29
  30 static lua_LHFunction old_linehook = NULL;
  31 static lua_CHFunction old_callhook = NULL;
  32
  33
  34 static handler lreset (void) {
  35   return signal(SIGINT, laction);
  36 }
  37
  38
  39 static void lstop (void) {
  40   lua_setlinehook(old_linehook);
  41   lua_setcallhook(old_callhook);
  42   lreset();
  43   lua_error("interrupted!");
  44 }
  45
  46
  47 static void laction (int i) {
  48   signal(SIGINT, SIG_DFL); /* if another SIGINT happens before lstop,
  49                               terminate process (default action) */
  50   old_linehook = lua_setlinehook((lua_LHFunction)lstop);
  51   old_callhook = lua_setcallhook((lua_CHFunction)lstop);
  52 }
  53
  54
  55 static int ldo (int (*f)(char *), char *name) {
  56   int res;
  57   handler h = lreset();
  58   res = f(name);  /* dostring | dofile */
  59   signal(SIGINT, h);  /* restore old action */
  60   return res;
  61 }
  62
  63
  64 static void print_message (void) {
  65   fprintf(stderr,
  66 "Lua: command line options:\n"
  67 "  -v       print version information\n"
  68 "  -d       turn debug on\n"
  69 "  -e stat  dostring `stat'\n"
  70 "  -q       interactive mode without prompt\n"
  71 "  -i       interactive mode with prompt\n"
  72 "  -        executes stdin as a file\n"
  73 "  a=b      sets global `a' with string `b'\n"
  74 "  name     dofile `name'\n\n");
  75 }
  76
  77
  78 static void assign (char *arg) {
  79   if (strlen(arg) >= 500)
  80     fprintf(stderr, "lua: shell argument too long");
  81   else {
  82     char buffer[500];
  83     char *eq = strchr(arg, '=');
  84     lua_pushstring(eq+1);
  85     strncpy(buffer, arg, eq-arg);
  86     buffer[eq-arg] = 0;
  87     lua_setglobal(buffer);
  88   }
  89 }
  90
  91
  92 static void manual_input (int prompt) {
  93   int cont = 1;
  94   while (cont) {
  95     char buffer[BUFSIZ];
  96     int i = 0;
  97     lua_beginblock();
  98     if (prompt)
  99       printf("%s", lua_getstring(lua_getglobal("_PROMPT")));
 100     for(;;) {
 101       int c = getchar();
 102       if (c == EOF) {
 103         cont = 0;
 104         break;
 105       }
 106       else if (c == '\n') {
 107         if (i>0 && buffer[i-1] == '\\')
 108           buffer[i-1] = '\n';
 109         else break;
 110       }
 111       else if (i >= BUFSIZ-1) {
 112         fprintf(stderr, "lua: argument line too long\n");
 113         break;
 114       }
 115       else buffer[i++] = (char)c;
 116     }
 117     buffer[i] = '\0';
 118     ldo(lua_dostring, buffer);
 119     lua_endblock();
 120   }
 121   printf("\n");
 122 }
 123
 124
 125 int main (int argc, char *argv[])
 126 {
 127   int i;
 128   lua_open();
 129   lua_pushstring("> "); lua_setglobal("_PROMPT");
 130   lua_userinit();
 131   if (argc < 2) {  /* no arguments? */
 132     if (isatty(0)) {
 133       printf("%s  %s\n", LUA_VERSION, LUA_COPYRIGHT);
 134       manual_input(1);
 135     }
 136     else
 137       ldo(lua_dofile, NULL);  /* executes stdin as a file */
 138   }
 139   else for (i=1; i<argc; i++) {
 140     if (argv[i][0] == '-') {  /* option? */
 141       switch (argv[i][1]) {
 142         case 0:
 143           ldo(lua_dofile, NULL);  /* executes stdin as a file */
 144           break;
 145         case 'i':
 146           manual_input(1);
 147           break;
 148         case 'q':
 149           manual_input(0);
 150           break;
 151         case 'd':
 152           lua_setdebug(1);
 153           break;
 154         case 'v':
 155           printf("%s  %s\n(written by %s)\n\n",
 156                  LUA_VERSION, LUA_COPYRIGHT, LUA_AUTHORS);
 157           break;
 158         case 'e':
 159           i++;
 160           if (ldo(lua_dostring, argv[i]) != 0) {
 161             fprintf(stderr, "lua: error running argument `%s'\n", argv[i]);
 162             return 1;
 163           }
 164           break;
 165         default:
 166           print_message();
 167           exit(1);
 168       }
 169     }
 170     else if (strchr(argv[i], '='))
 171       assign(argv[i]);
 172     else {
 173       int result = ldo(lua_dofile, argv[i]);
 174       if (result) {
 175         if (result == 2) {
 176           fprintf(stderr, "lua: cannot execute file ");
 177           perror(argv[i]);
 178         }
 179         exit(1);
 180       }
 181     }
 182   }
 183 #ifdef DEBUG
 184   lua_close();
 185 #endif
 186   return 0;
 187 }
 188