1 /*
2 * Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers.
3 * All rights reserved.
4 *
5 * By using this file, you agree to the terms and conditions set
6 * forth in the LICENSE file which can be found at the top level of
7 * the sendmail distribution.
8 *
9 */
10
11 #include <sm/gen.h>
12 SM_RCSID("@(#)$Id: assert.c,v 1.25.2.1 2003/12/05 22:44:17 ca Exp $")
13
14 /*
15 ** Abnormal program termination and assertion checking.
16 ** For documentation, see assert.html.
17 */
18
19 #include <signal.h>
20 #include <stdlib.h>
21 #include <unistd.h>
22
23 #include <sm/assert.h>
24 #include <sm/exc.h>
25 #include <sm/io.h>
26 #include <sm/varargs.h>
27
28 /*
29 ** Debug categories that are used to guard expensive assertion checks.
30 */
31
32 SM_DEBUG_T SmExpensiveAssert = SM_DEBUG_INITIALIZER("sm_check_assert",
33 "@(#)$Debug: sm_check_assert - check assertions $");
34
35 SM_DEBUG_T SmExpensiveRequire = SM_DEBUG_INITIALIZER("sm_check_require",
36 "@(#)$Debug: sm_check_require - check function preconditions $");
37
38 SM_DEBUG_T SmExpensiveEnsure = SM_DEBUG_INITIALIZER("sm_check_ensure",
39 "@(#)$Debug: sm_check_ensure - check function postconditions $");
40
41 /*
42 ** Debug category: send self SIGSTOP on fatal error,
43 ** so that you can run a debugger on the stopped process.
44 */
45
46 SM_DEBUG_T SmAbortStop = SM_DEBUG_INITIALIZER("sm_abort_stop",
47 "@(#)$Debug: sm_abort_stop - stop process on fatal error $");
48
49 /*
50 ** SM_ABORT_DEFAULTHANDLER -- Default procedure for abnormal program
51 ** termination.
52 **
53 ** The goal is to display an error message without disturbing the
54 ** process state too much, then dump core.
55 **
56 ** Parameters:
57 ** filename -- filename (can be NULL).
58 ** lineno -- line number.
59 ** msg -- message.
60 **
61 ** Returns:
62 ** doesn't return.
63 */
64
65 static void
66 sm_abort_defaulthandler __P((
67 const char *filename,
68 int lineno,
69 const char *msg));
70
71 static void
sm_abort_defaulthandler(filename,lineno,msg)72 sm_abort_defaulthandler(filename, lineno, msg)
73 const char *filename;
74 int lineno;
75 const char *msg;
76 {
77 if (filename != NULL)
78 sm_io_fprintf(smioerr, SM_TIME_DEFAULT, "%s:%d: %s\n", filename,
79 lineno, msg);
80 else
81 sm_io_fprintf(smioerr, SM_TIME_DEFAULT, "%s\n", msg);
82 sm_io_flush(smioerr, SM_TIME_DEFAULT);
83 #ifdef SIGSTOP
84 if (sm_debug_active(&SmAbortStop, 1))
85 kill(getpid(), SIGSTOP);
86 #endif /* SIGSTOP */
87 abort();
88 }
89
90 /*
91 ** This is the action to be taken to cause abnormal program termination.
92 */
93
94 static SM_ABORT_HANDLER_T SmAbortHandler = sm_abort_defaulthandler;
95
96 /*
97 ** SM_ABORT_SETHANDLER -- Set handler for SM_ABORT()
98 **
99 ** This allows you to set a handler function for causing abnormal
100 ** program termination; it is called when a logic bug is detected.
101 **
102 ** Parameters:
103 ** f -- handler.
104 **
105 ** Returns:
106 ** none.
107 */
108
109 void
sm_abort_sethandler(f)110 sm_abort_sethandler(f)
111 SM_ABORT_HANDLER_T f;
112 {
113 if (f == NULL)
114 SmAbortHandler = sm_abort_defaulthandler;
115 else
116 SmAbortHandler = f;
117 }
118
119 /*
120 ** SM_ABORT -- Call it when you have detected a logic bug.
121 **
122 ** Parameters:
123 ** fmt -- format string.
124 ** ... -- arguments.
125 **
126 ** Returns:
127 ** doesn't.
128 */
129
130 void SM_DEAD_D
131 #if SM_VA_STD
sm_abort(char * fmt,...)132 sm_abort(char *fmt, ...)
133 #else /* SM_VA_STD */
134 sm_abort(fmt, va_alist)
135 char *fmt;
136 va_dcl
137 #endif /* SM_VA_STD */
138 {
139 char msg[128];
140 SM_VA_LOCAL_DECL
141
142 SM_VA_START(ap, fmt);
143 sm_vsnprintf(msg, sizeof msg, fmt, ap);
144 SM_VA_END(ap);
145 sm_abort_at(NULL, 0, msg);
146 }
147
148 /*
149 ** SM_ABORT_AT -- Initiate abnormal program termination.
150 **
151 ** This is the low level function that is called to initiate abnormal
152 ** program termination. It prints an error message and terminates the
153 ** program. It is called by sm_abort and by the assertion macros.
154 ** If filename != NULL then filename and lineno specify the line of source
155 ** code at which the bug was detected.
156 **
157 ** Parameters:
158 ** filename -- filename (can be NULL).
159 ** lineno -- line number.
160 ** msg -- message.
161 **
162 ** Returns:
163 ** doesn't.
164 */
165
166 void SM_DEAD_D
sm_abort_at(filename,lineno,msg)167 sm_abort_at(filename, lineno, msg)
168 const char *filename;
169 int lineno;
170 const char *msg;
171 {
172 SM_TRY
173 (*SmAbortHandler)(filename, lineno, msg);
174 SM_EXCEPT(exc, "*")
175 sm_io_fprintf(smioerr, SM_TIME_DEFAULT,
176 "exception raised by abort handler:\n");
177 sm_exc_print(exc, smioerr);
178 sm_io_flush(smioerr, SM_TIME_DEFAULT);
179 SM_END_TRY
180
181 /*
182 ** SmAbortHandler isn't supposed to return.
183 ** Since it has, let's make sure that the program is terminated.
184 */
185
186 abort();
187 }
188