epan/except.h

   1 /*
   2  * Portable Exception Handling for ANSI C.
   3  * Copyright (C) 1999 Kaz Kylheku <kaz@ashi.footprints.net>
   4  *
   5  * Free Software License:
   6  *
   7  * All rights are reserved by the author, with the following exceptions:
   8  * Permission is granted to freely reproduce and distribute this software,
   9  * possibly in exchange for a fee, provided that this copyright notice appears
  10  * intact. Permission is also granted to adapt this software to produce
  11  * derivative works, as long as the modified versions carry this copyright
  12  * notice and additional notices stating that the work has been modified.
  13  * This source code may be translated into executable form and incorporated
  14  * into proprietary software; there is no requirement for such software to
  15  * contain a copyright notice related to this source.
  16  *
  17  * $Id$
  18  * $Name:  $
  19  */
  20
  21 /**
  22  * @file
  23  * Portable Exception Handling for ANSI C.<BR>
  24  * Modified to support throwing an exception with a null message pointer,
  25  * and to have the message not be const (as we generate messages with
  26  * "g_strdup_sprintf()", which means they need to be freed; using
  27  * a null message means that we don't have to use a special string
  28  * for exceptions with no message, and don't have to worry about
  29  * not freeing that).
  30  */
  31
  32 #ifndef XCEPT_H
  33 #define XCEPT_H
  34
  35 #include <glib.h>
  36 #include <setjmp.h>
  37 #include <stdlib.h>
  38 #include <assert.h>
  39 #include "ws_symbol_export.h"
  40
  41 #define XCEPT_GROUP_ANY 0
  42 #define XCEPT_CODE_ANY  0
  43 #define XCEPT_BAD_ALLOC 1
  44
  45 #ifdef __cplusplus
  46 extern "C" {
  47 #endif
  48
  49 enum { except_no_call, except_call };
  50
  51 typedef struct {
  52     unsigned long except_group;
  53     unsigned long except_code;
  54 } except_id_t;
  55
  56 typedef struct {
  57     except_id_t volatile except_id;
  58     const char *volatile except_message;
  59     void *volatile except_dyndata;
  60 } except_t;
  61
  62 struct except_cleanup {
  63     void (*except_func)(void *);
  64     void *except_context;
  65 };
  66
  67 struct except_catch {
  68     const except_id_t *except_id;
  69     size_t except_size;
  70     except_t except_obj;
  71     jmp_buf except_jmp;
  72 };
  73
  74 enum except_stacktype {
  75     XCEPT_CLEANUP, XCEPT_CATCHER
  76 };
  77
  78 struct except_stacknode {
  79     struct except_stacknode *except_down;
  80     enum except_stacktype except_type;
  81     union {
  82         struct except_catch *except_catcher;
  83         struct except_cleanup *except_cleanup;
  84     } except_info;
  85 };
  86
  87 /* private functions made external so they can be used in macros */
  88 extern void except_setup_clean(struct except_stacknode *,
  89         struct except_cleanup *, void (*)(void *), void *);
  90 WS_DLL_PUBLIC void except_setup_try(struct except_stacknode *,
  91         struct except_catch *, const except_id_t [], size_t);
  92 WS_DLL_PUBLIC struct except_stacknode *except_pop(void);
  93
  94 /* public interface functions */
  95 WS_DLL_PUBLIC int except_init(void);
  96 WS_DLL_PUBLIC void except_deinit(void);
  97 WS_DLL_PUBLIC WS_MSVC_NORETURN void except_rethrow(except_t *) G_GNUC_NORETURN;
  98 WS_DLL_PUBLIC WS_MSVC_NORETURN void except_throw(long, long, const char *) G_GNUC_NORETURN;
  99 WS_DLL_PUBLIC WS_MSVC_NORETURN void except_throwd(long, long, const char *, void *) G_GNUC_NORETURN;
 100 WS_DLL_PUBLIC WS_MSVC_NORETURN void except_throwf(long, long, const char *, ...) G_GNUC_NORETURN;
 101 WS_DLL_PUBLIC void (*except_unhandled_catcher(void (*)(except_t *)))(except_t *);
 102 extern unsigned long except_code(except_t *);
 103 extern unsigned long except_group(except_t *);
 104 extern const char *except_message(except_t *);
 105 extern void *except_data(except_t *);
 106 WS_DLL_PUBLIC void *except_take_data(except_t *);
 107 WS_DLL_PUBLIC void except_set_allocator(void *(*)(size_t), void (*)(void *));
 108 WS_DLL_PUBLIC void *except_alloc(size_t);
 109 WS_DLL_PUBLIC void except_free(void *);
 110
 111 #define except_code(E) ((E)->except_id.except_code)
 112 #define except_group(E) ((E)->except_id.except_group)
 113 #define except_message(E) ((E)->except_message)
 114 #define except_data(E) ((E)->except_dyndata)
 115
 116 #ifdef __cplusplus
 117 }
 118 #endif
 119
 120 /*
 121  * void except_cleanup_push(void (*)(void *), void *);
 122  * void except_cleanup_pop(int);
 123  * void except_checked_cleanup_pop(void (*)(void *), int);
 124  * void except_try_push(const except_id_t [], size_t, except_t **);
 125  * void except_try_pop(void);
 126  */
 127
 128 #define except_cleanup_push(F, C)                               \
 129     {                                                           \
 130         struct except_stacknode except_sn;                      \
 131         struct except_cleanup except_cl;                        \
 132         except_setup_clean(&except_sn, &except_cl, F, C)
 133
 134 #define except_cleanup_pop(E)                                   \
 135         except_pop();                                           \
 136         if (E)                                                  \
 137             except_cl.except_func(except_cl.except_context);    \
 138     }
 139
 140 #define except_checked_cleanup_pop(F, E)                        \
 141         except_pop();                                           \
 142         assert (except_cl.except_func == (F));                  \
 143         if (E)                                                  \
 144             except_cl.except_func(except_cl.except_context);    \
 145     }
 146
 147
 148 /* --- Variants to allow nesting of except_cleanup_push w/o "shadowing" variables */
 149 #define except_cleanup_push_pfx(pfx, F, C)                              \
 150     {                                                                   \
 151         struct except_stacknode pfx##_except_sn;                        \
 152         struct except_cleanup pfx##_except_cl;                          \
 153         except_setup_clean(&pfx##_except_sn, &pfx##_except_cl, F, C)
 154
 155 #define except_cleanup_pop_pfx(pfx, E)                                  \
 156         except_pop();                                                   \
 157         if (E)                                                          \
 158             pfx##_except_cl.except_func(pfx##_except_cl.except_context);\
 159     }
 160
 161 #define except_checked_cleanup_pop_pfx(pfx, F, E)                       \
 162         except_pop();                                                   \
 163         assert (pfx##_except_cl.except_func == (F));                    \
 164         if (E)                                                          \
 165             pfx##_except_cl.except_func(pfx##_except_cl.except_context);\
 166     }
 167 /* ---------- */
 168
 169
 170 #define except_try_push(ID, NUM, PPE)                           \
 171      {                                                          \
 172         struct except_stacknode except_sn;                      \
 173         struct except_catch except_ch;                          \
 174         except_setup_try(&except_sn, &except_ch, ID, NUM);      \
 175         if (setjmp(except_ch.except_jmp))                       \
 176             *(PPE) = &except_ch.except_obj;                     \
 177         else                                                    \
 178             *(PPE) = 0
 179
 180 #define except_try_pop()                                        \
 181         except_free(except_ch.except_obj.except_dyndata);       \
 182         except_pop();                                           \
 183     }
 184
 185 #endif /* XCEPT_H */