1 /*
2  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
3  *
4  * SPDX-License-Identifier: MPL-2.0
5  *
6  * This Source Code Form is subject to the terms of the Mozilla Public
7  * License, v. 2.0. If a copy of the MPL was not distributed with this
8  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
9  *
10  * See the COPYRIGHT file distributed with this work for additional
11  * information regarding copyright ownership.
12  */
13 
14 /*! \file */
15 
16 #include <stdio.h>
17 #include <stdlib.h>
18 
19 #include <isc/assertions.h>
20 #include <isc/backtrace.h>
21 #include <isc/print.h>
22 #include <isc/result.h>
23 
24 /*
25  * The maximum number of stack frames to dump on assertion failure.
26  */
27 #ifndef BACKTRACE_MAXFRAME
28 #define BACKTRACE_MAXFRAME 128
29 #endif /* ifndef BACKTRACE_MAXFRAME */
30 
31 /*%
32  * Forward.
33  */
34 static void
35 default_callback(const char *, int, isc_assertiontype_t, const char *);
36 
37 static isc_assertioncallback_t isc_assertion_failed_cb = default_callback;
38 
39 /*%
40  * Public.
41  */
42 
43 /*% assertion failed handler */
44 /* coverity[+kill] */
45 void
isc_assertion_failed(const char * file,int line,isc_assertiontype_t type,const char * cond)46 isc_assertion_failed(const char *file, int line, isc_assertiontype_t type,
47 		     const char *cond) {
48 	isc_assertion_failed_cb(file, line, type, cond);
49 	abort();
50 	/* NOTREACHED */
51 }
52 
53 /*% Set callback. */
54 void
isc_assertion_setcallback(isc_assertioncallback_t cb)55 isc_assertion_setcallback(isc_assertioncallback_t cb) {
56 	if (cb == NULL) {
57 		isc_assertion_failed_cb = default_callback;
58 	} else {
59 		isc_assertion_failed_cb = cb;
60 	}
61 }
62 
63 /*% Type to Text */
64 const char *
isc_assertion_typetotext(isc_assertiontype_t type)65 isc_assertion_typetotext(isc_assertiontype_t type) {
66 	const char *result;
67 
68 	/*
69 	 * These strings have purposefully not been internationalized
70 	 * because they are considered to essentially be keywords of
71 	 * the ISC development environment.
72 	 */
73 	switch (type) {
74 	case isc_assertiontype_require:
75 		result = "REQUIRE";
76 		break;
77 	case isc_assertiontype_ensure:
78 		result = "ENSURE";
79 		break;
80 	case isc_assertiontype_insist:
81 		result = "INSIST";
82 		break;
83 	case isc_assertiontype_invariant:
84 		result = "INVARIANT";
85 		break;
86 	default:
87 		result = "UNKNOWN";
88 	}
89 	return (result);
90 }
91 
92 /*
93  * Private.
94  */
95 
96 static void
default_callback(const char * file,int line,isc_assertiontype_t type,const char * cond)97 default_callback(const char *file, int line, isc_assertiontype_t type,
98 		 const char *cond) {
99 	void *tracebuf[BACKTRACE_MAXFRAME];
100 	int i, nframes;
101 	const char *logsuffix = ".";
102 	const char *fname;
103 	isc_result_t result;
104 
105 	result = isc_backtrace_gettrace(tracebuf, BACKTRACE_MAXFRAME, &nframes);
106 	if (result == ISC_R_SUCCESS && nframes > 0) {
107 		logsuffix = ", back trace";
108 	}
109 
110 	fprintf(stderr, "%s:%d: %s(%s) failed%s\n", file, line,
111 		isc_assertion_typetotext(type), cond, logsuffix);
112 
113 	if (result == ISC_R_SUCCESS) {
114 		for (i = 0; i < nframes; i++) {
115 			unsigned long offset;
116 
117 			fname = NULL;
118 			result = isc_backtrace_getsymbol(tracebuf[i], &fname,
119 							 &offset);
120 			if (result == ISC_R_SUCCESS) {
121 				fprintf(stderr, "#%d %p in %s()+0x%lx\n", i,
122 					tracebuf[i], fname, offset);
123 			} else {
124 				fprintf(stderr, "#%d %p in ??\n", i,
125 					tracebuf[i]);
126 			}
127 		}
128 	}
129 	fflush(stderr);
130 }
131