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 = 0;
  82         char *fmt = "%s%s%s";
  83
  84         str = get_error_string ();
  85
  86         if ((error == NULL) || (*error == 0))
  87           error = "";
  88         else if (SLang_Error == SL_UNKNOWN_ERROR)
  89           /* Do not display an unknown error message if error is non-NULL */
  90           str = "";
  91         else {
  92           fmt = "%s%s: %s";
  93           len = 2;      /* ": " */
  94         }
  95
  96         len += strlen (sle) + strlen (str) + strlen(error) + 1 /* trailing 0 */;
  97
  98         err = err_buf;
  99         if (len > sizeof (err_buf))
 100           {
 101              if (NULL == (malloced_err_buf = SLmalloc (len)))
 102                err = NULL;
 103              else
 104                err = malloced_err_buf;
 105           }
 106
 107         if (err != NULL) sprintf (err, fmt, sle, str, error);
 108         else err = "Out of memory";
 109      }
 110
 111    if (SLang_Error_Hook == NULL)
 112      {
 113         fputs (err, stderr);
 114         fputs("\r\n", stderr);
 115         fflush (stderr);
 116      }
 117    else
 118      (*SLang_Error_Hook)(err);
 119
 120    SLfree (malloced_err_buf);
 121 }
 122
 123 void SLang_verror (int err_code, char *fmt, ...)
 124 {
 125    va_list ap;
 126    char err [1024];
 127
 128    if (err_code == 0) err_code = SL_INTRINSIC_ERROR;
 129    if (SLang_Error == 0) SLang_Error = err_code;
 130
 131    if (fmt != NULL)
 132      {
 133         va_start(ap, fmt);
 134         (void) _SLvsnprintf (err, sizeof (err), fmt, ap);
 135         fmt = err;
 136         va_end(ap);
 137      }
 138
 139    SLang_doerror (fmt);
 140 }
 141
 142 void SLang_exit_error (char *fmt, ...)
 143 {
 144    va_list ap;
 145
 146    va_start (ap, fmt);
 147    if (SLang_Exit_Error_Hook != NULL)
 148      {
 149         (*SLang_Exit_Error_Hook) (fmt, ap);
 150         exit (1);
 151      }
 152
 153    if (fmt != NULL)
 154      {
 155         vfprintf (stderr, fmt, ap);
 156         fputs ("\r\n", stderr);
 157         fflush (stderr);
 158      }
 159    va_end (ap);
 160
 161    exit (1);
 162 }
 163
 164 void SLang_vmessage (char *fmt, ...)
 165 {
 166    va_list ap;
 167
 168    if (fmt == NULL)
 169      return;
 170
 171    va_start (ap, fmt);
 172
 173    if (SLang_VMessage_Hook != NULL)
 174      (*SLang_VMessage_Hook) (fmt, ap);
 175    else
 176      {
 177         vfprintf (stdout, fmt, ap);
 178         fputs ("\r\n", stdout);
 179      }
 180
 181    va_end (ap);
 182 }