source/arith/errors.c

   1 /*
   2   $Id: errors.c,v 1.6 2006/03/15 19:59:37 verdoolaege Exp $
   3
   4   Exception management.
   5   See "arithmetic_errors.h".
   6
   7   $Log: errors.c,v $
   8   Revision 1.6  2006/03/15 19:59:37  verdoolaege
   9   arith: add some missing consts
  10
  11   Revision 1.5  2004/08/31 18:01:56  verdoolaege
  12   remove warning
  13
  14   Revision 1.4  2004/02/11 10:19:54  verdoolaege
  15   add const qualifier
  16
  17   Revision 1.3  2004/02/08 21:53:27  kienhuis
  18   Update from Fabien Coelho, via Bart Kienhuis
  19
  20   I've updated here in the C3/Linear library the arithmetic_error
  21   package that I developped (with others) to handle exceptions in C.
  22   It adds a simple callback feature which is needed for pips here.
  23   If you do not use it, it should not harm;-)
  24
  25   Revision 1.27  2003/09/04 09:40:37  coelho
  26   init added.
  27   verbosity mask added.
  28
  29   Revision 1.26  2003/09/03 14:05:20  coelho
  30   push/pop callbacks called.
  31
  32   Revision 1.20  2003/08/18 09:55:09  coelho
  33   get_exception_name added...
  34
  35   Revision 1.19  2003/06/13 13:59:07  coelho
  36   const out.
  37
  38   Revision 1.18  2003/06/13 13:54:47  coelho
  39   hop.
  40
  41   Revision 1.17  2002/04/02 08:44:54  coelho
  42   timeout_error ajoute.
  43
  44   Revision 1.16  2000/10/27 13:26:03  ancourt
  45   exception_thrown -> linear_number_of_exception_thrown
  46
  47   Revision 1.15  2000/07/27 15:21:55  coelho
  48   message++
  49
  50   Revision 1.14  2000/07/27 14:59:59  coelho
  51   trace added.
  52
  53   Revision 1.13  2000/07/26 08:41:23  coelho
  54   the_last_just_thrown_exception management added.
  55
  56   Revision 1.12  1998/10/26 18:48:34  coelho
  57   message++.
  58
  59   Revision 1.11  1998/10/26 14:38:06  coelho
  60   constants back in.
  61
  62   Revision 1.10  1998/10/26 14:35:47  coelho
  63   constants in .h.
  64
  65   Revision 1.9  1998/10/24 15:36:22  coelho
  66   better exception error messages...
  67
  68   Revision 1.8  1998/10/24 15:19:17  coelho
  69   more verbose throw...
  70
  71   Revision 1.7  1998/10/24 14:31:13  coelho
  72   new stack implementation.
  73   checks for matching catch/uncatch.
  74   debug mode.
  75
  76   Revision 1.6  1998/10/24 09:31:06  coelho
  77   RCS headers.
  78   'const' tried.
  79
  80 */
  81
  82 #include <stdio.h>
  83 #include <stdlib.h>
  84 #include <string.h>
  85
  86 #include "arithmetique.h"
  87
  88 /* global constants to designate exceptions.
  89    to be put in the type field bellow.
  90    cproto 4.6 does not line 'const'...
  91 */
  92 unsigned int overflow_error = 1;
  93 unsigned int simplex_arithmetic_error = 2;
  94 unsigned int user_exception_error = 4;
  95 unsigned int parser_exception_error = 8;
  96 unsigned int timeout_error = 16;
  97
  98 /* catch all */
  99 unsigned int any_exception_error = ~0;
 100
 101
 102 /*
 103  * On a few systems, type boolean and/or its values FALSE, TRUE may appear
 104  * in standard header files.  Or you may have conflicts with application-
 105  * specific header files that you want to include together with these files.
 106  * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
 107  */
 108
 109 #ifndef HAVE_BOOLEAN
 110 typedef int boolean;
 111 #endif
 112 #ifndef FALSE                   /* in case these macros already exist */
 113 #define FALSE   0               /* values of boolean */
 114 #endif
 115 #ifndef TRUE
 116 #define TRUE    1
 117 #endif
 118
 119 const char *get_exception_name(unsigned int exception)
 120 {
 121   if (exception==overflow_error)
 122     return "overflow_error exception";
 123   if (exception==simplex_arithmetic_error)
 124     return "simplex_arithmetic_error exception";
 125   if (exception==user_exception_error)
 126     return "user_exception_error exception";
 127   if (exception==parser_exception_error)
 128     return "parser_exception_error exception";
 129   if (exception==timeout_error)
 130     return "timeout_error exception";
 131   if (exception==any_exception_error)
 132     return "all exceptions mask";
 133
 134   return "unknown or mixed exception";
 135 }
 136
 137 /* keep track of last thrown exception for RETHROW()
 138  */
 139 unsigned int the_last_just_thrown_exception = 0;
 140
 141 /* whether to run in debug mode (that is to trace catch/uncatch/throw)
 142  */
 143 static int linear_exception_debug_mode = FALSE;
 144 static unsigned int linear_exception_verbose = 1 | 2 | 16 ;
 145
 146 /* A structure for the exception stack.
 147  */
 148 typedef struct
 149 {
 150   /* exception type.
 151    */
 152   int what;
 153
 154   /* where to jump to.
 155    */
 156   jmp_buf where;
 157
 158   /* location of the CATCH to be matched against the UNCATCH.
 159    */
 160   const char * function;
 161   const char * file;
 162   int    line;
 163 }
 164   linear_exception_holder;
 165
 166 /* exception stack.
 167    maximum extension.
 168    current index (next available bucket)
 169  */
 170 #define MAX_STACKED_CONTEXTS 64
 171 static linear_exception_holder exception_stack[MAX_STACKED_CONTEXTS];
 172 static int exception_index = 0;
 173
 174 /* callbacks...
 175  */
 176 static exception_callback_t push_callback = NULL;
 177 static exception_callback_t pop_callback = NULL;
 178
 179 void set_exception_callbacks(exception_callback_t push,
 180                              exception_callback_t pop)
 181 {
 182   if (push_callback!=NULL || pop_callback!=NULL)
 183   {
 184     fprintf(stderr, "exception callbacks already defined! (%p, %p)\n",
 185             push_callback, pop_callback);
 186     abort();
 187   }
 188
 189   push_callback = push;
 190   pop_callback = pop;
 191 }
 192
 193 /* total number of exceptions thrown, for statistics.
 194  */
 195 int linear_number_of_exception_thrown = 0;
 196
 197 /* dump stack
 198  */
 199 void dump_exception_stack_to_file(FILE * f)
 200 {
 201   int i;
 202   fprintf(f, "[dump_exception_stack_to_file] size=%d\n", exception_index);
 203   for (i=0; i<exception_index; i++)
 204   {
 205     fprintf(f,
 206             "%d: [%s:%d in %s (%d)]\n",
 207             i,
 208             exception_stack[i].file,
 209             exception_stack[i].line,
 210             exception_stack[i].function,
 211             exception_stack[i].what);
 212   }
 213   fprintf(f, "\n");
 214 }
 215
 216 void dump_exception_stack()
 217 {
 218   dump_exception_stack_to_file(stderr);
 219 }
 220
 221 #define exception_debug_message(type)                             \
 222     fprintf(stderr, "%s[%s:%d %s (%d)/%d]\n",                     \
 223             type, file, line, function, what, exception_index)
 224
 225 #define exception_debug_trace(type) \
 226     if (linear_exception_debug_mode) { exception_debug_message(type); }
 227
 228
 229 /* push a what exception on stack.
 230  */
 231 jmp_buf *
 232 push_exception_on_stack(
 233     int what,
 234     const char * function,
 235     const char * file,
 236     int line)
 237 {
 238   exception_debug_trace("PUSH ");
 239
 240   if (exception_index==MAX_STACKED_CONTEXTS)
 241   {
 242     exception_debug_message("push");
 243     fprintf(stderr, "exception stack overflow\n");
 244     dump_exception_stack();
 245     abort();
 246   }
 247
 248   if (push_callback) push_callback(file, function, line);
 249
 250   the_last_just_thrown_exception = 0;
 251
 252   exception_stack[exception_index].what = what;
 253   exception_stack[exception_index].function = function;
 254   exception_stack[exception_index].file = file;
 255   exception_stack[exception_index].line = line;
 256
 257   return & exception_stack[exception_index++].where;
 258 }
 259
 260 #if !defined(same_string_p)
 261 #define same_string_p(s1, s2) (strcmp((s1),(s2))==0)
 262 #endif
 263
 264 /* pop a what exception.
 265    check for any mismatch!
 266  */
 267 void
 268 pop_exception_from_stack(
 269     int what,
 270     const char * function,
 271     const char * file,
 272     int line)
 273 {
 274   exception_debug_trace("POP  ");
 275
 276   if (exception_index==0)
 277   {
 278     exception_debug_message("pop");
 279     fprintf(stderr, "exception stack underflow\n");
 280     dump_exception_stack();
 281     abort();
 282   }
 283
 284   if (pop_callback) pop_callback(file, function, line);
 285
 286   exception_index--;
 287   the_last_just_thrown_exception = 0;
 288
 289   if ((exception_stack[exception_index].what != what) ||
 290       !same_string_p(exception_stack[exception_index].file, file) ||
 291       !same_string_p(exception_stack[exception_index].function, function))
 292   {
 293     exception_debug_message("pop");
 294     fprintf(stderr,
 295             "exception stack mismatch at depth=%d:\n"
 296             "   CATCH: %s:%d in %s (%d)\n"
 297             " UNCATCH: %s:%d in %s (%d)\n",
 298             exception_index,
 299             exception_stack[exception_index].file,
 300             exception_stack[exception_index].line,
 301             exception_stack[exception_index].function,
 302             exception_stack[exception_index].what,
 303             file, line, function, what);
 304     dump_exception_stack();
 305     abort();
 306   }
 307 }
 308
 309 /* throws an exception of a given type by searching for
 310    the specified 'what' in the current exception stack.
 311 */
 312 void throw_exception(
 313     int what,
 314     const char * function,
 315     const char * file,
 316     int line)
 317 {
 318   int i;
 319
 320   exception_debug_trace("THROW");
 321
 322   the_last_just_thrown_exception = what; /* for rethrow */
 323
 324   for (i=exception_index-1; i>=0; i--)
 325   {
 326     if (pop_callback)
 327       /* pop with push parameters! */
 328       pop_callback(exception_stack[i].file,
 329                    exception_stack[i].function,
 330                    exception_stack[i].line);
 331
 332     if (exception_stack[i].what & what)
 333     {
 334       exception_index = i;
 335       linear_number_of_exception_thrown++;
 336
 337       if (linear_exception_debug_mode)
 338         fprintf(stderr, "---->[%s:%d %s (%d)/%d]\n",
 339                 exception_stack[i].file,
 340                 exception_stack[i].line,
 341                 exception_stack[i].function,
 342                 exception_stack[i].what,
 343                 i);
 344
 345       /* trace some exceptions... */
 346       if (linear_exception_verbose & what)
 347         fprintf(stderr, "exception %d/%d: %s(%s:%d) -> %s(%s:%d)\n",
 348                 what, exception_stack[i].what,
 349                 function, file, line,
 350                 exception_stack[i].function,
 351                 exception_stack[i].file,
 352                 exception_stack[i].line);
 353
 354       longjmp(exception_stack[i].where, 0);
 355     }
 356   }
 357
 358   /* error. */
 359   exception_debug_message("throw");
 360   fprintf(stderr,
 361           "exception not found in stack:\n"
 362           "an exception was THROWN without a proper matching CATCH\n");
 363   dump_exception_stack();
 364   abort();
 365 }
 366
 367 void linear_initialize_exception_stack(
 368   unsigned int verbose_exceptions,
 369   exception_callback_t push,
 370   exception_callback_t pop)
 371 {
 372   linear_exception_verbose = verbose_exceptions;
 373   set_exception_callbacks(push, pop);
 374 }