0875b58f |
1 | /* -*-c-*- |
2 | * |
de907046 |
3 | * $Id: exc.c,v 1.4 1999/05/17 20:35:30 mdw Exp $ |
0875b58f |
4 | * |
5 | * Structured exception handling in C |
6 | * |
7 | * (c) 1998 Straylight/Edgeware |
8 | */ |
9 | |
c846879c |
10 | /*----- Licensing notice --------------------------------------------------* |
0875b58f |
11 | * |
12 | * This file is part of the mLib utilities library. |
13 | * |
14 | * mLib is free software; you can redistribute it and/or modify |
c846879c |
15 | * it under the terms of the GNU Library General Public License as |
16 | * published by the Free Software Foundation; either version 2 of the |
17 | * License, or (at your option) any later version. |
18 | * |
0875b58f |
19 | * mLib is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
c846879c |
22 | * GNU Library General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU Library General Public |
0bd98442 |
25 | * License along with mLib; if not, write to the Free |
26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
27 | * MA 02111-1307, USA. |
0875b58f |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: exc.c,v $ |
de907046 |
33 | * Revision 1.4 1999/05/17 20:35:30 mdw |
34 | * Output uncaught exception types in hex, because they're easier to |
35 | * translate that way. |
36 | * |
0bd98442 |
37 | * Revision 1.3 1999/05/06 19:51:35 mdw |
38 | * Reformatted the LGPL notice a little bit. |
39 | * |
c846879c |
40 | * Revision 1.2 1999/05/05 18:50:31 mdw |
41 | * Change licensing conditions to LGPL. |
42 | * |
43 | * Revision 1.1.1.1 1998/06/17 23:44:42 mdw |
44 | * Initial version of mLib |
0875b58f |
45 | * |
46 | */ |
47 | |
48 | #include <stdarg.h> |
49 | #include <stdlib.h> |
50 | #include <stdio.h> |
51 | |
52 | #include "exc.h" |
53 | |
54 | /*----- Global variables --------------------------------------------------*/ |
55 | |
56 | __exc_hnd *__exc_list = 0; |
57 | |
58 | /*----- Functions ---------------------------------------------------------*/ |
59 | |
60 | /* --- @exc__duff@ --- * |
61 | * |
62 | * Arguments: @exc_extype type@ = type of duff exception |
63 | * @exc_exval val@ = extra data supplied |
64 | * |
65 | * Returns: Doesn't |
66 | * |
67 | * Use: Default handler when everything goes wrong. |
68 | */ |
69 | |
70 | static void exc__duff(exc_extype type, exc_exval val) |
71 | { |
de907046 |
72 | fprintf(stderr, "fatal error: uncaught exception (type = %lx)\n", type); |
0875b58f |
73 | abort(); |
74 | } |
75 | |
76 | /* --- @exc__duffproc@ --- * |
77 | * |
78 | * Current handler when there are no more exceptions left. |
79 | */ |
80 | |
81 | static exc__uncaught exc__duffproc = exc__duff; |
82 | |
83 | /* --- @exc_uncaught@ --- * |
84 | * |
85 | * Arguments: @void (*proc)(exc_extype type, exc_exval val) = new handler |
86 | * |
87 | * Returns: Pointer to the old handler value. |
88 | * |
89 | * Use: Sets the handler for uncaught exceptions. |
90 | */ |
91 | |
92 | exc__uncaught exc_uncaught(exc__uncaught proc) |
93 | { |
94 | exc__uncaught p = exc__duffproc; |
95 | if (proc) |
96 | exc__duffproc = proc; |
97 | return (p); |
98 | } |
99 | |
100 | /* --- @__exc_throw@ --- * |
101 | * |
102 | * Arguments: @exc_extype type@ = type of exception to throw |
103 | * |
104 | * Returns: Doesn't |
105 | * |
106 | * Use: NOT FOR USER CONSUMPTION. Reads an appropriate exception |
107 | * value and throws an exception. |
108 | */ |
109 | |
110 | void __exc_throw(exc_extype type, ...) |
111 | { |
112 | va_list ap; |
113 | exc_exval v; |
114 | |
115 | va_start(ap, type); |
116 | switch (type & 0xC0) { |
117 | case EXC_NOVAL: |
118 | v.i = 0; |
119 | break; |
120 | case EXC_INTVAL: |
121 | v.i = va_arg(ap, int); |
122 | break; |
123 | case EXC_PTRVAL: |
124 | v.p = va_arg(ap, void *); |
125 | break; |
126 | case EXC_STRVAL: |
127 | v.s = va_arg(ap, char *); |
128 | break; |
129 | } |
130 | va_end(ap); |
131 | __exc_rethrow(type, v); |
132 | } |
133 | |
134 | /* --- @__exc_rethrow@ --- * |
135 | * |
136 | * Arguments: @exc_extype type@ = type of exception to throw |
137 | * @exc_exval val@ = value of exception to throw |
138 | * |
139 | * Returns: Doesn't |
140 | * |
141 | * Use: NOT FOR USER CONSUMPTION. Does the donkey-work of raising |
142 | * an exception. |
143 | */ |
144 | |
145 | void __exc_rethrow(exc_extype type, exc_exval val) |
146 | { |
147 | __exc_hnd *p = __exc_list; |
148 | if (!p) |
149 | exc__duffproc(type, val); |
150 | p->type = type; |
151 | p->val = val; |
152 | __exc_list = p->next; |
153 | longjmp(p->buf, type); |
154 | } |
155 | |
156 | /*----- That's all, folks -------------------------------------------------*/ |