0875b58f |
1 | /* -*-c-*- |
2 | * |
ff0f0220 |
3 | * $Id: exc.c,v 1.5 1999/05/19 20:27:11 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 $ |
ff0f0220 |
33 | * Revision 1.5 1999/05/19 20:27:11 mdw |
34 | * Change naming to match newer mLib conventions. |
35 | * |
de907046 |
36 | * Revision 1.4 1999/05/17 20:35:30 mdw |
37 | * Output uncaught exception types in hex, because they're easier to |
38 | * translate that way. |
39 | * |
0bd98442 |
40 | * Revision 1.3 1999/05/06 19:51:35 mdw |
41 | * Reformatted the LGPL notice a little bit. |
42 | * |
c846879c |
43 | * Revision 1.2 1999/05/05 18:50:31 mdw |
44 | * Change licensing conditions to LGPL. |
45 | * |
46 | * Revision 1.1.1.1 1998/06/17 23:44:42 mdw |
47 | * Initial version of mLib |
0875b58f |
48 | * |
49 | */ |
50 | |
51 | #include <stdarg.h> |
52 | #include <stdlib.h> |
53 | #include <stdio.h> |
54 | |
55 | #include "exc.h" |
56 | |
57 | /*----- Global variables --------------------------------------------------*/ |
58 | |
59 | __exc_hnd *__exc_list = 0; |
60 | |
61 | /*----- Functions ---------------------------------------------------------*/ |
62 | |
ff0f0220 |
63 | /* --- @duff@ --- * |
0875b58f |
64 | * |
65 | * Arguments: @exc_extype type@ = type of duff exception |
66 | * @exc_exval val@ = extra data supplied |
67 | * |
68 | * Returns: Doesn't |
69 | * |
70 | * Use: Default handler when everything goes wrong. |
71 | */ |
72 | |
ff0f0220 |
73 | static void duff(exc_extype type, exc_exval val) |
0875b58f |
74 | { |
de907046 |
75 | fprintf(stderr, "fatal error: uncaught exception (type = %lx)\n", type); |
0875b58f |
76 | abort(); |
77 | } |
78 | |
ff0f0220 |
79 | /* --- @duffproc@ --- * |
0875b58f |
80 | * |
81 | * Current handler when there are no more exceptions left. |
82 | */ |
83 | |
ff0f0220 |
84 | static exc__uncaught duffproc = duff; |
0875b58f |
85 | |
86 | /* --- @exc_uncaught@ --- * |
87 | * |
88 | * Arguments: @void (*proc)(exc_extype type, exc_exval val) = new handler |
89 | * |
90 | * Returns: Pointer to the old handler value. |
91 | * |
92 | * Use: Sets the handler for uncaught exceptions. |
93 | */ |
94 | |
95 | exc__uncaught exc_uncaught(exc__uncaught proc) |
96 | { |
ff0f0220 |
97 | exc__uncaught p = duffproc; |
0875b58f |
98 | if (proc) |
ff0f0220 |
99 | duffproc = proc; |
0875b58f |
100 | return (p); |
101 | } |
102 | |
103 | /* --- @__exc_throw@ --- * |
104 | * |
105 | * Arguments: @exc_extype type@ = type of exception to throw |
106 | * |
107 | * Returns: Doesn't |
108 | * |
109 | * Use: NOT FOR USER CONSUMPTION. Reads an appropriate exception |
110 | * value and throws an exception. |
111 | */ |
112 | |
113 | void __exc_throw(exc_extype type, ...) |
114 | { |
115 | va_list ap; |
116 | exc_exval v; |
117 | |
118 | va_start(ap, type); |
119 | switch (type & 0xC0) { |
120 | case EXC_NOVAL: |
121 | v.i = 0; |
122 | break; |
123 | case EXC_INTVAL: |
124 | v.i = va_arg(ap, int); |
125 | break; |
126 | case EXC_PTRVAL: |
127 | v.p = va_arg(ap, void *); |
128 | break; |
129 | case EXC_STRVAL: |
130 | v.s = va_arg(ap, char *); |
131 | break; |
132 | } |
133 | va_end(ap); |
134 | __exc_rethrow(type, v); |
135 | } |
136 | |
137 | /* --- @__exc_rethrow@ --- * |
138 | * |
139 | * Arguments: @exc_extype type@ = type of exception to throw |
140 | * @exc_exval val@ = value of exception to throw |
141 | * |
142 | * Returns: Doesn't |
143 | * |
144 | * Use: NOT FOR USER CONSUMPTION. Does the donkey-work of raising |
145 | * an exception. |
146 | */ |
147 | |
148 | void __exc_rethrow(exc_extype type, exc_exval val) |
149 | { |
150 | __exc_hnd *p = __exc_list; |
151 | if (!p) |
ff0f0220 |
152 | duffproc(type, val); |
0875b58f |
153 | p->type = type; |
154 | p->val = val; |
155 | __exc_list = p->next; |
156 | longjmp(p->buf, type); |
157 | } |
158 | |
159 | /*----- That's all, folks -------------------------------------------------*/ |