source: src/libcfa/interpose.c@ 589a70b

ADT aaron-thesis arm-eh ast-experimental cleanup-dtors deferred_resn demangler enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr no_list persistent-indexer pthread-emulation qualifiedEnum
Last change on this file since 589a70b was de94a60, checked in by Thierry Delisle <tdelisle@…>, 7 years ago

some more work on kernel doubly linked lists and fixed segfault in abort message
  • Property mode set to 100644
File size: 8.5 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// interpose.c --
8//
9// Author : Thierry Delisle
10// Created On : Wed Mar 29 16:10:31 2017
11// Last Modified By : Peter A. Buhr
12// Last Modified On : Sat May 5 11:37:35 2018
13// Update Count : 111
14//
15
16#include <stdarg.h> // va_start, va_end
17#include <string.h> // strlen
18#include <unistd.h> // _exit, getpid
19#define __USE_GNU
20#include <signal.h>
21#undef __USE_GNU
22extern "C" {
23#include <dlfcn.h> // dlopen, dlsym
24#include <execinfo.h> // backtrace, messages
25}
26
27#include "bits/debug.h"
28#include "bits/defs.h"
29#include "bits/signal.h" // sigHandler_?
30#include "startup.h" // STARTUP_PRIORITY_CORE
31
32//=============================================================================================
33// Interposing helpers
34//=============================================================================================
35
36typedef void (* generic_fptr_t)(void);
37generic_fptr_t interpose_symbol( const char * symbol, const char * version ) {
38 const char * error;
39
40 static void * library;
41 if ( ! library ) {
42 #if defined( RTLD_NEXT )
43 library = RTLD_NEXT;
44 #else
45 // missing RTLD_NEXT => must hard-code library name, assuming libstdc++
46 library = dlopen( "libc.so.6", RTLD_LAZY );
47 error = dlerror();
48 if ( error ) {
49 abort( "interpose_symbol : failed to open libc, %s\n", error );
50 }
51 #endif
52 } // if
53
54 union { generic_fptr_t fptr; void * ptr; } originalFunc;
55
56 #if defined( _GNU_SOURCE )
57 if ( version ) {
58 originalFunc.ptr = dlvsym( library, symbol, version );
59 } else {
60 originalFunc.ptr = dlsym( library, symbol );
61 }
62 #else
63 originalFunc.ptr = dlsym( library, symbol );
64 #endif // _GNU_SOURCE
65
66 error = dlerror();
67 if ( error ) abort( "interpose_symbol : internal error, %s\n", error );
68
69 return originalFunc.fptr;
70}
71
72#define INTERPOSE_LIBC( x, ver ) __cabi_libc.x = (typeof(__cabi_libc.x))interpose_symbol( #x, ver )
73
74//=============================================================================================
75// Interposition Startup logic
76//=============================================================================================
77
78void sigHandler_segv ( __CFA_SIGPARMS__ );
79void sigHandler_ill ( __CFA_SIGPARMS__ );
80void sigHandler_fpe ( __CFA_SIGPARMS__ );
81void sigHandler_abort( __CFA_SIGPARMS__ );
82void sigHandler_term ( __CFA_SIGPARMS__ );
83
84struct {
85 void (* exit)( int ) __attribute__(( __noreturn__ ));
86 void (* abort)( void ) __attribute__(( __noreturn__ ));
87} __cabi_libc;
88
89extern "C" {
90 void __cfaabi_interpose_startup(void) __attribute__(( constructor( STARTUP_PRIORITY_CORE ) ));
91 void __cfaabi_interpose_startup( void ) {
92 const char *version = NULL;
93
94#pragma GCC diagnostic push
95#pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
96 INTERPOSE_LIBC( abort, version );
97 INTERPOSE_LIBC( exit , version );
98#pragma GCC diagnostic pop
99
100 // Failure handler
101 __cfaabi_sigaction( SIGSEGV, sigHandler_segv , SA_SIGINFO );
102 __cfaabi_sigaction( SIGBUS , sigHandler_segv , SA_SIGINFO );
103 __cfaabi_sigaction( SIGILL , sigHandler_ill , SA_SIGINFO );
104 __cfaabi_sigaction( SIGFPE , sigHandler_fpe , SA_SIGINFO );
105 __cfaabi_sigaction( SIGABRT, sigHandler_abort, SA_SIGINFO | SA_RESETHAND);
106 __cfaabi_sigaction( SIGTERM, sigHandler_term , SA_SIGINFO );
107 __cfaabi_sigaction( SIGINT , sigHandler_term , SA_SIGINFO );
108 }
109}
110
111//=============================================================================================
112// Terminating Signals logic
113//=============================================================================================
114
115// Forward declare abort after the __typeof__ call to avoid ambiguities
116void exit( int status, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ ));
117void abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ ));
118
119extern "C" {
120 void abort( void ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) {
121 abort( NULL );
122 }
123
124 void __cabi_abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ )) {
125 va_list argp;
126 va_start( argp, fmt );
127 abort( fmt, argp );
128 va_end( argp );
129 }
130
131 void exit( int status ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) {
132 __cabi_libc.exit( status );
133 }
134}
135
136void * kernel_abort ( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return NULL; }
137void kernel_abort_msg( void * data, char * buffer, int size ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
138int kernel_abort_lastframe( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 4; }
139
140enum { abort_text_size = 1024 };
141static char abort_text[ abort_text_size ];
142static int abort_lastframe;
143
144void exit( int status, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ )) {
145 va_list args;
146 va_start( args, fmt );
147 vfprintf( stderr, fmt, args );
148 va_end( args );
149 __cabi_libc.exit( status );
150}
151
152void abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ )) {
153 void * kernel_data = kernel_abort(); // must be done here to lock down kernel
154 int len;
155
156 abort_lastframe = kernel_abort_lastframe();
157 len = snprintf( abort_text, abort_text_size, "Cforall Runtime error (UNIX pid:%ld) ", (long int)getpid() ); // use UNIX pid (versus getPid)
158 __cfaabi_dbg_bits_write( abort_text, len );
159
160 if ( fmt ) {
161 va_list args;
162 va_start( args, fmt );
163
164 len = vsnprintf( abort_text, abort_text_size, fmt, args );
165 va_end( args );
166 __cfaabi_dbg_bits_write( abort_text, len );
167
168 if ( fmt[strlen( fmt ) - 1] != '\n' ) { // add optional newline if missing at the end of the format text
169 __cfaabi_dbg_bits_write( "\n", 1 );
170 }
171 }
172
173 kernel_abort_msg( kernel_data, abort_text, abort_text_size );
174 __cabi_libc.abort();
175}
176
177static void __cfaabi_backtrace() {
178 enum {
179 Frames = 50, // maximum number of stack frames
180 Start = 8, // skip first N stack frames
181 };
182
183 void * array[Frames];
184 size_t size = backtrace( array, Frames );
185 char ** messages = backtrace_symbols( array, size );
186
187 // find executable name
188 *index( messages[0], '(' ) = '\0';
189 __cfaabi_dbg_bits_print_nolock( "Stack back trace for: %s\n", messages[0]);
190
191 for ( int i = Start; i < size - abort_lastframe && messages != NULL; i += 1 ) {
192 char * name = NULL, * offset_begin = NULL, * offset_end = NULL;
193
194 for ( char * p = messages[i]; *p; ++p ) {
195 //__cfaabi_dbg_bits_print_nolock( "X %s\n", p);
196 // find parantheses and +offset
197 if ( *p == '(' ) {
198 name = p;
199 }
200 else if ( *p == '+' ) {
201 offset_begin = p;
202 }
203 else if ( *p == ')' ) {
204 offset_end = p;
205 break;
206 }
207 }
208
209 // if line contains symbol print it
210 int frameNo = i - Start;
211 if ( name && offset_begin && offset_end && name < offset_begin ) {
212 // delimit strings
213 *name++ = '\0';
214 *offset_begin++ = '\0';
215 *offset_end++ = '\0';
216
217 __cfaabi_dbg_bits_print_nolock( "(%i) %s : %s + %s %s\n", frameNo, messages[i], name, offset_begin, offset_end);
218 }
219 // otherwise, print the whole line
220 else {
221 __cfaabi_dbg_bits_print_nolock( "(%i) %s\n", frameNo, messages[i] );
222 }
223 }
224 free( messages );
225}
226
227void sigHandler_segv( __CFA_SIGPARMS__ ) {
228 abort( "Addressing invalid memory at location %p\n"
229 "Possible cause is reading outside the address space or writing to a protected area within the address space with an invalid pointer or subscript.\n",
230 sfp->si_addr );
231}
232
233void sigHandler_ill( __CFA_SIGPARMS__ ) {
234 abort( "Executing illegal instruction at location %p.\n"
235 "Possible cause is stack corruption.\n",
236 sfp->si_addr );
237}
238
239void sigHandler_fpe( __CFA_SIGPARMS__ ) {
240 const char * msg;
241
242 choose( sfp->si_code ) {
243 case FPE_INTDIV, FPE_FLTDIV: msg = "divide by zero";
244 case FPE_FLTOVF: msg = "overflow";
245 case FPE_FLTUND: msg = "underflow";
246 case FPE_FLTRES: msg = "inexact result";
247 case FPE_FLTINV: msg = "invalid operation";
248 default: msg = "unknown";
249 } // choose
250 abort( "Computation error %s at location %p.\n", msg, sfp->si_addr );
251}
252
253void sigHandler_abort( __CFA_SIGPARMS__ ) {
254 __cfaabi_backtrace();
255
256 // reset default signal handler
257 __cfaabi_sigdefault( SIGABRT );
258
259 raise( SIGABRT );
260}
261
262void sigHandler_term( __CFA_SIGPARMS__ ) {
263 abort( "Application stopped by %s signal.", sig == SIGINT ? "an interrupt (SIGINT)" : "a terminate (SIGTERM)" );
264}
265
266// Local Variables: //
267// mode: c //
268// tab-width: 4 //
269// End: //
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