slang/slerr.c

   1 /* error handling common to all routines. */
   2 /* Copyright (c) 1992, 1999, 2001, 2002 John E. Davis
   3  * This file is part of the S-Lang library.
   4  *
   5  * You may distribute under the terms of either the GNU General Public
   6  * License or the Perl Artistic License.
   7  */
   8
   9 #include "slinclud.h"
  10
  11 #include "slang.h"
  12 #include "_slang.h"
  13
  14 void (*SLang_VMessage_Hook) (char *, va_list);
  15 void (*SLang_Error_Hook)(char *);
  16 void (*SLang_Exit_Error_Hook)(char *, va_list);
  17 volatile int SLang_Error = 0;
  18 char *SLang_Error_Message;
  19 volatile int SLKeyBoard_Quit = 0;
  20
  21 static char *get_error_string (void)
  22 {
  23    char *str;
  24
  25    if (!SLang_Error) SLang_Error = SL_UNKNOWN_ERROR;
  26    if (SLang_Error_Message != NULL) str = SLang_Error_Message;
  27    else switch(SLang_Error)
  28      {
  29       case SL_NOT_IMPLEMENTED: str = "Not Implemented"; break;
  30       case SL_APPLICATION_ERROR: str = "Application Error"; break;
  31       case SL_VARIABLE_UNINITIALIZED: str = "Variable Uninitialized"; break;
  32       case SL_MALLOC_ERROR : str = "Malloc Error"; break;
  33       case SL_INTERNAL_ERROR: str = "Internal Error"; break;
  34       case SL_STACK_OVERFLOW: str = "Stack Overflow"; break;
  35       case SL_STACK_UNDERFLOW: str = "Stack Underflow"; break;
  36       case SL_INTRINSIC_ERROR: str = "Intrinsic Error"; break;
  37       case SL_USER_BREAK: str = "User Break"; break;
  38       case SL_UNDEFINED_NAME: str = "Undefined Name"; break;
  39       case SL_SYNTAX_ERROR: str = "Syntax Error"; break;
  40       case SL_DUPLICATE_DEFINITION: str = "Duplicate Definition"; break;
  41       case SL_TYPE_MISMATCH: str = "Type Mismatch"; break;
  42       case SL_READONLY_ERROR: str = "Variable is read-only"; break;
  43       case SL_DIVIDE_ERROR: str = "Divide by zero"; break;
  44       case SL_OBJ_NOPEN: str = "Object not opened"; break;
  45       case SL_OBJ_UNKNOWN: str = "Object unknown"; break;
  46       case SL_INVALID_PARM: str = "Invalid Parameter"; break;
  47       case SL_TYPE_UNDEFINED_OP_ERROR:
  48         str = "Operation not defined for datatype"; break;
  49       case SL_USER_ERROR:
  50         str = "User Error"; break;
  51       case SL_USAGE_ERROR:
  52         str = "Illegal usage of function";
  53         break;
  54       case SL_FLOATING_EXCEPTION:
  55         str = "Floating Point Exception";
  56         break;
  57       case SL_UNKNOWN_ERROR:
  58       default: str = "Unknown Error Code";
  59      }
  60
  61    SLang_Error_Message = NULL;
  62    return str;
  63 }
  64
  65 void SLang_doerror (char *error)
  66 {
  67    char *str = NULL;
  68    char *err;
  69    char *malloced_err_buf;
  70    char err_buf [1024];
  71
  72    malloced_err_buf = NULL;
  73
  74    if (((SLang_Error == SL_USER_ERROR)
  75         || (SLang_Error == SL_USAGE_ERROR))
  76        && (error != NULL) && (*error != 0))
  77      err = error;
  78    else
  79      {
  80         char *sle = "S-Lang Error: ";
  81         unsigned int len;
  82         char *fmt;
  83
  84         str = get_error_string ();
  85
  86         fmt = "%s%s%s";
  87         if ((error == NULL) || (*error == 0))
  88           error = "";
  89         else if (SLang_Error == SL_UNKNOWN_ERROR)
  90           /* Do not display an unknown error message if error is non-NULL */
  91           str = "";
  92         else
  93           fmt = "%s%s: %s";
  94
  95         len = strlen (sle) + strlen (str) + strlen(error) + 1;
  96
  97         err = err_buf;
  98         if (len >= sizeof (err_buf))
  99           {
 100              if (NULL == (malloced_err_buf = SLmalloc (len)))
 101                err = NULL;
 102              else
 103                err = malloced_err_buf;
 104           }
 105
 106         if (err != NULL) sprintf (err, fmt, sle, str, error);
 107         else err = "Out of memory";
 108      }
 109
 110    if (SLang_Error_Hook == NULL)
 111      {
 112         fputs (err, stderr);
 113         fputs("\r\n", stderr);
 114         fflush (stderr);
 115      }
 116    else
 117      (*SLang_Error_Hook)(err);
 118
 119    SLfree (malloced_err_buf);
 120 }
 121
 122 void SLang_verror (int err_code, char *fmt, ...)
 123 {
 124    va_list ap;
 125    char err [1024];
 126
 127    if (err_code == 0) err_code = SL_INTRINSIC_ERROR;
 128    if (SLang_Error == 0) SLang_Error = err_code;
 129
 130    if (fmt != NULL)
 131      {
 132         va_start(ap, fmt);
 133         (void) _SLvsnprintf (err, sizeof (err), fmt, ap);
 134         fmt = err;
 135         va_end(ap);
 136      }
 137
 138    SLang_doerror (fmt);
 139 }
 140
 141 void SLang_exit_error (char *fmt, ...)
 142 {
 143    va_list ap;
 144
 145    va_start (ap, fmt);
 146    if (SLang_Exit_Error_Hook != NULL)
 147      {
 148         (*SLang_Exit_Error_Hook) (fmt, ap);
 149         exit (1);
 150      }
 151
 152    if (fmt != NULL)
 153      {
 154         vfprintf (stderr, fmt, ap);
 155         fputs ("\r\n", stderr);
 156         fflush (stderr);
 157      }
 158    va_end (ap);
 159
 160    exit (1);
 161 }
 162
 163 void SLang_vmessage (char *fmt, ...)
 164 {
 165    va_list ap;
 166
 167    if (fmt == NULL)
 168      return;
 169
 170    va_start (ap, fmt);
 171
 172    if (SLang_VMessage_Hook != NULL)
 173      (*SLang_VMessage_Hook) (fmt, ap);
 174    else
 175      {
 176         vfprintf (stdout, fmt, ap);
 177         fputs ("\r\n", stdout);
 178      }
 179
 180    va_end (ap);
 181 }