inout.c

   1 /*
   2 ** inout.c
   3 ** Provide function to realise the input/output function and debugger
   4 ** facilities.
   5 **
   6 ** Waldemar Celes Filho
   7 ** TeCGraf - PUC-Rio
   8 ** 11 May 93
   9 */
  10
  11 #include <stdio.h>
  12 #include <string.h>
  13
  14 #include "opcode.h"
  15 #include "hash.h"
  16 #include "inout.h"
  17 #include "table.h"
  18
  19 /* Exported variables */
  20 int lua_linenumber;
  21 int lua_debug;
  22 int lua_debugline;
  23
  24 /* Internal variables */
  25 #ifndef MAXFUNCSTACK
  26 #define MAXFUNCSTACK 32
  27 #endif
  28 static struct { int file; int function; } funcstack[MAXFUNCSTACK];
  29 static int nfuncstack=0;
  30
  31 static FILE *fp;
  32 static char *st;
  33 static void (*usererror) (char *s);
  34
  35 /*
  36 ** Function to set user function to handle errors.
  37 */
  38 void lua_errorfunction (void (*fn) (char *s))
  39 {
  40  usererror = fn;
  41 }
  42
  43 /*
  44 ** Function to get the next character from the input file
  45 */
  46 static int fileinput (void)
  47 {
  48  int c = fgetc (fp);
  49  return (c == EOF ? 0 : c);
  50 }
  51
  52 /*
  53 ** Function to unget the next character from to input file
  54 */
  55 static void fileunput (int c)
  56 {
  57  ungetc (c, fp);
  58 }
  59
  60 /*
  61 ** Function to get the next character from the input string
  62 */
  63 static int stringinput (void)
  64 {
  65  st++;
  66  return (*(st-1));
  67 }
  68
  69 /*
  70 ** Function to unget the next character from to input string
  71 */
  72 static void stringunput (int c)
  73 {
  74  st--;
  75 }
  76
  77 /*
  78 ** Function to open a file to be input unit.
  79 ** Return 0 on success or 1 on error.
  80 */
  81 int lua_openfile (char *fn)
  82 {
  83  lua_linenumber = 1;
  84  lua_setinput (fileinput);
  85  lua_setunput (fileunput);
  86  fp = fopen (fn, "r");
  87  if (fp == NULL) return 1;
  88  if (lua_addfile (fn)) return 1;
  89  return 0;
  90 }
  91
  92 /*
  93 ** Function to close an opened file
  94 */
  95 void lua_closefile (void)
  96 {
  97  if (fp != NULL)
  98  {
  99   fclose (fp);
 100   fp = NULL;
 101  }
 102 }
 103
 104 /*
 105 ** Function to open a string to be input unit
 106 */
 107 int lua_openstring (char *s)
 108 {
 109  lua_linenumber = 1;
 110  lua_setinput (stringinput);
 111  lua_setunput (stringunput);
 112  st = s;
 113  {
 114   char sn[64];
 115   sprintf (sn, "String: %10.10s...", s);
 116   if (lua_addfile (sn)) return 1;
 117  }
 118  return 0;
 119 }
 120
 121 /*
 122 ** Call user function to handle error messages, if registred. Or report error
 123 ** using standard function (fprintf).
 124 */
 125 void lua_error (char *s)
 126 {
 127  if (usererror != NULL) usererror (s);
 128  else                       fprintf (stderr, "lua: %s\n", s);
 129 }
 130
 131 /*
 132 ** Called to execute  SETFUNCTION opcode, this function pushs a function into
 133 ** function stack. Return 0 on success or 1 on error.
 134 */
 135 int lua_pushfunction (int file, int function)
 136 {
 137  if (nfuncstack >= MAXFUNCSTACK-1)
 138  {
 139   lua_error ("function stack overflow");
 140   return 1;
 141  }
 142  funcstack[nfuncstack].file = file;
 143  funcstack[nfuncstack].function = function;
 144  nfuncstack++;
 145  return 0;
 146 }
 147
 148 /*
 149 ** Called to execute  RESET opcode, this function pops a function from
 150 ** function stack.
 151 */
 152 void lua_popfunction (void)
 153 {
 154  nfuncstack--;
 155 }
 156
 157 /*
 158 ** Report bug building a message and sending it to lua_error function.
 159 */
 160 void lua_reportbug (char *s)
 161 {
 162  char msg[1024];
 163  strcpy (msg, s);
 164  if (lua_debugline != 0)
 165  {
 166   int i;
 167   if (nfuncstack > 0)
 168   {
 169    sprintf (strchr(msg,0),
 170          "\n\tin statement begining at line %d in function \"%s\" of file \"%s\"",
 171          lua_debugline, s_name(funcstack[nfuncstack-1].function),
 172          lua_file[funcstack[nfuncstack-1].file]);
 173    sprintf (strchr(msg,0), "\n\tactive stack\n");
 174    for (i=nfuncstack-1; i>=0; i--)
 175     sprintf (strchr(msg,0), "\t-> function \"%s\" of file \"%s\"\n",
 176                             s_name(funcstack[i].function),
 177                             lua_file[funcstack[i].file]);
 178   }
 179   else
 180   {
 181    sprintf (strchr(msg,0),
 182          "\n\tin statement begining at line %d of file \"%s\"",
 183          lua_debugline, lua_filename());
 184   }
 185  }
 186  lua_error (msg);
 187 }
 188