1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <stdio.h>
18 #include <stdlib.h>
19 
20 #ifdef HAVE_ANDROID_OS
21 #include <android/log.h>
22 #else
23 #include <stdarg.h>
24 #include <iostream>
25 #endif
26 
27 #include "sigchain.h"
28 
29 #define ATTRIBUTE_UNUSED __attribute__((__unused__))
30 
31 // We cannot annotate the declarations, as they are not no-return in the non-dummy version.
32 #pragma GCC diagnostic push
33 #pragma GCC diagnostic ignored "-Wunknown-pragmas"
34 #pragma GCC diagnostic ignored "-Wmissing-noreturn"
35 
log(const char * format,...)36 static void log(const char* format, ...) {
37   char buf[256];
38   va_list ap;
39   va_start(ap, format);
40   vsnprintf(buf, sizeof(buf), format, ap);
41 #ifdef HAVE_ANDROID_OS
42   __android_log_write(ANDROID_LOG_ERROR, "libsigchain", buf);
43 #else
44   std::cout << buf << "\n";
45 #endif
46   va_end(ap);
47 }
48 
49 namespace art {
50 
51 
ClaimSignalChain(int signal ATTRIBUTE_UNUSED,struct sigaction * oldaction ATTRIBUTE_UNUSED)52 extern "C" void ClaimSignalChain(int signal ATTRIBUTE_UNUSED,
53                                  struct sigaction* oldaction ATTRIBUTE_UNUSED) {
54   log("ClaimSignalChain is not exported by the main executable.");
55   abort();
56 }
57 
UnclaimSignalChain(int signal ATTRIBUTE_UNUSED)58 extern "C" void UnclaimSignalChain(int signal ATTRIBUTE_UNUSED) {
59   log("UnclaimSignalChain is not exported by the main executable.");
60   abort();
61 }
62 
InvokeUserSignalHandler(int sig ATTRIBUTE_UNUSED,siginfo_t * info ATTRIBUTE_UNUSED,void * context ATTRIBUTE_UNUSED)63 extern "C" void InvokeUserSignalHandler(int sig ATTRIBUTE_UNUSED,
64                                         siginfo_t* info ATTRIBUTE_UNUSED,
65                                         void* context ATTRIBUTE_UNUSED) {
66   log("InvokeUserSignalHandler is not exported by the main executable.");
67   abort();
68 }
69 
InitializeSignalChain()70 extern "C" void InitializeSignalChain() {
71   log("InitializeSignalChain is not exported by the main executable.");
72   abort();
73 }
74 
EnsureFrontOfChain(int signal ATTRIBUTE_UNUSED,struct sigaction * expected_action ATTRIBUTE_UNUSED)75 extern "C" void EnsureFrontOfChain(int signal ATTRIBUTE_UNUSED,
76                                    struct sigaction* expected_action ATTRIBUTE_UNUSED) {
77   log("EnsureFrontOfChain is not exported by the main executable.");
78   abort();
79 }
80 
SetSpecialSignalHandlerFn(int signal ATTRIBUTE_UNUSED,SpecialSignalHandlerFn fn ATTRIBUTE_UNUSED)81 extern "C" void SetSpecialSignalHandlerFn(int signal ATTRIBUTE_UNUSED,
82                                           SpecialSignalHandlerFn fn ATTRIBUTE_UNUSED) {
83   log("SetSpecialSignalHandlerFn is not exported by the main executable.");
84   abort();
85 }
86 
87 #pragma GCC diagnostic pop
88 
89 }  // namespace art
90