source: libcfa/src/interpose.cfa@ 57dff2f

ADT ast-experimental enum forall-pointer-decay jacob/cs343-translation pthread-emulation qualifiedEnum
Last change on this file since 57dff2f was 96f002c1, checked in by Thierry Delisle <tdelisle@…>, 4 years ago

Added new device folder and cpu file to libcfa
  • Property mode set to 100644
File size: 11.5 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 : Fri Mar 13 17:35:37 2020
13// Update Count : 178
14//
15
16#include <stdarg.h> // va_start, va_end
17#include <stdio.h>
18#include <string.h> // strlen
19#include <unistd.h> // _exit, getpid
20#define __USE_GNU
21#include <signal.h>
22#undef __USE_GNU
23extern "C" {
24#include <dlfcn.h> // dlopen, dlsym
25#include <execinfo.h> // backtrace, messages
26}
27
28#include "bits/debug.hfa"
29#include "bits/defs.hfa"
30#include "bits/signal.hfa" // sigHandler_?
31#include "startup.hfa" // STARTUP_PRIORITY_CORE
32#include <assert.h>
33
34//=============================================================================================
35// Interposing helpers
36//=============================================================================================
37
38void preload_libgcc(void) {
39 dlopen( "libgcc_s.so.1", RTLD_NOW );
40 if ( const char * error = dlerror() ) abort( "interpose_symbol : internal error pre-loading libgcc, %s\n", error );
41}
42
43typedef void (* generic_fptr_t)(void);
44generic_fptr_t interpose_symbol( const char symbol[], const char version[] ) {
45 const char * error;
46
47 static void * library;
48 if ( ! library ) {
49 #if defined( RTLD_NEXT )
50 library = RTLD_NEXT;
51 #else
52 // missing RTLD_NEXT => must hard-code library name, assuming libstdc++
53 library = dlopen( "libc.so.6", RTLD_LAZY );
54 error = dlerror();
55 if ( error ) {
56 abort( "interpose_symbol : failed to open libc, %s\n", error );
57 }
58 #endif
59 } // if
60
61 union { generic_fptr_t fptr; void * ptr; } originalFunc;
62
63 #if defined( _GNU_SOURCE )
64 if ( version ) {
65 originalFunc.ptr = dlvsym( library, symbol, version );
66 } else {
67 originalFunc.ptr = dlsym( library, symbol );
68 }
69 #else
70 originalFunc.ptr = dlsym( library, symbol );
71 #endif // _GNU_SOURCE
72
73 error = dlerror();
74 if ( error ) abort( "interpose_symbol : internal error, %s\n", error );
75
76 return originalFunc.fptr;
77}
78
79#define INTERPOSE_LIBC( x, ver ) __cabi_libc.x = (typeof(__cabi_libc.x))interpose_symbol( #x, ver )
80
81//=============================================================================================
82// Interposition Startup logic
83//=============================================================================================
84
85void sigHandler_segv( __CFA_SIGPARMS__ );
86void sigHandler_ill ( __CFA_SIGPARMS__ );
87void sigHandler_fpe ( __CFA_SIGPARMS__ );
88void sigHandler_abrt( __CFA_SIGPARMS__ );
89void sigHandler_term( __CFA_SIGPARMS__ );
90
91struct {
92 void (* exit)( int ) __attribute__(( __noreturn__ ));
93 void (* abort)( void ) __attribute__(( __noreturn__ ));
94} __cabi_libc;
95
96extern "C" {
97 void __cfaabi_interpose_startup( void ) {
98 const char *version = 0p;
99
100 preload_libgcc();
101
102#pragma GCC diagnostic push
103#pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
104 INTERPOSE_LIBC( abort, version );
105 INTERPOSE_LIBC( exit , version );
106#pragma GCC diagnostic pop
107
108 // As a precaution (and necessity), errors that result in termination are delivered on a separate stack because
109 // task stacks might be very small (4K) and the signal delivery corrupts memory to the point that a clean
110 // shutdown is impossible. Also, when a stack overflow encounters the non-accessible sentinel page (debug only)
111 // and generates a segment fault, the signal cannot be delivered on the sentinel page. Finally, calls to abort
112 // print a stack trace that uses substantial stack space.
113
114 #define MINSTKSZ SIGSTKSZ * 8
115 static char stack[MINSTKSZ] __attribute__(( aligned (16) ));
116 static stack_t ss;
117
118 ss.ss_sp = stack;
119 ss.ss_size = MINSTKSZ;
120 ss.ss_flags = 0;
121 if ( sigaltstack( &ss, 0p ) == -1 ) {
122 abort( "__cfaabi_interpose_startup : internal error, sigaltstack error(%d) %s.", errno, strerror( errno ) );
123 } // if
124
125 // Failure handler
126 // internal errors
127 __cfaabi_sigaction( SIGSEGV, sigHandler_segv, SA_SIGINFO | SA_ONSTACK ); // Invalid memory reference (default: Core)
128 __cfaabi_sigaction( SIGBUS , sigHandler_segv, SA_SIGINFO | SA_ONSTACK ); // Bus error, bad memory access (default: Core)
129 __cfaabi_sigaction( SIGILL , sigHandler_ill , SA_SIGINFO | SA_ONSTACK ); // Illegal Instruction (default: Core)
130 __cfaabi_sigaction( SIGFPE , sigHandler_fpe , SA_SIGINFO | SA_ONSTACK ); // Floating-point exception (default: Core)
131
132 // handlers to outside errors
133 // reset in-case they insist and send it over and over
134 __cfaabi_sigaction( SIGTERM, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Termination signal (default: Term)
135 __cfaabi_sigaction( SIGINT , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Interrupt from keyboard (default: Term)
136 __cfaabi_sigaction( SIGHUP , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Hangup detected on controlling terminal or death of controlling process (default: Term)
137 __cfaabi_sigaction( SIGQUIT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Quit from keyboard (default: Core)
138 __cfaabi_sigaction( SIGABRT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Abort signal from abort(3) (default: Core)
139 }
140}
141
142//=============================================================================================
143// Terminating Signals logic
144//=============================================================================================
145
146// Forward declare abort after the __typeof__ call to avoid ambiguities
147void exit( int status, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ ));
148void abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ ));
149void abort( bool signalAbort, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ ));
150void __abort( bool signalAbort, const char fmt[], va_list args ) __attribute__(( __nothrow__, __leaf__, __noreturn__ ));
151
152extern "C" {
153 void abort( void ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) {
154 abort( false, "%s", "" );
155 }
156
157 void __cabi_abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ )) {
158 va_list argp;
159 va_start( argp, fmt );
160 __abort( false, fmt, argp );
161 va_end( argp );
162 }
163
164 void exit( int status ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) {
165 __cabi_libc.exit( status );
166 }
167}
168
169// See concurrency/kernel.cfa and concurrency/preemption.cfa for strong definition used in multi-processor mode.
170void __kernel_abort_lock( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
171void __kernel_abort_msg( char buffer[], int size ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
172int __kernel_abort_lastframe( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 4; }
173
174enum { abort_text_size = 1024 };
175static char abort_text[ abort_text_size ];
176
177static void __cfaabi_backtrace( int start ) {
178 enum { Frames = 50, }; // maximum number of stack frames
179 int last = __kernel_abort_lastframe(); // skip last N stack frames
180
181 void * array[Frames];
182 size_t size = backtrace( array, Frames );
183 char ** messages = backtrace_symbols( array, size ); // does not demangle names
184
185 *index( messages[0], '(' ) = '\0'; // find executable name
186 __cfaabi_bits_print_nolock( STDERR_FILENO, "Stack back trace for: %s\n", messages[0]);
187
188 for ( unsigned int i = start; i < size - last && messages != 0p; i += 1 ) {
189 char * name = 0p, * offset_begin = 0p, * offset_end = 0p;
190
191 for ( char * p = messages[i]; *p; p += 1 ) { // find parantheses and +offset
192 //__cfaabi_bits_print_nolock( "X %s\n", p);
193 if ( *p == '(' ) {
194 name = p;
195 } else if ( *p == '+' ) {
196 offset_begin = p;
197 } else if ( *p == ')' ) {
198 offset_end = p;
199 break;
200 }
201 }
202
203 // if line contains symbol, print it
204 int frameNo = i - start;
205 if ( name && offset_begin && offset_end && name < offset_begin ) {
206 *name++ = '\0'; // delimit strings
207 *offset_begin++ = '\0';
208 *offset_end++ = '\0';
209
210 __cfaabi_bits_print_nolock( STDERR_FILENO, "(%i) %s : %s + %s %s\n", frameNo, messages[i], name, offset_begin, offset_end);
211 } else { // otherwise, print the whole line
212 __cfaabi_bits_print_nolock( STDERR_FILENO, "(%i) %s\n", frameNo, messages[i] );
213 }
214 }
215 free( messages );
216}
217
218void exit( int status, const char fmt[], ... ) {
219 va_list args;
220 va_start( args, fmt );
221 vfprintf( stderr, fmt, args );
222 va_end( args );
223 __cabi_libc.exit( status );
224}
225
226static volatile bool __abort_first = 0;
227
228// Cannot forward va_list.
229void __abort( bool signalAbort, const char fmt[], va_list args ) {
230 // Multiple threads can come here from multiple paths
231 // To make sure this is safe any concurrent/subsequent call to abort is redirected to libc-abort
232 bool first = ! __atomic_test_and_set( &__abort_first, __ATOMIC_SEQ_CST);
233
234 // Prevent preemption from kicking-in and messing with the abort
235 __kernel_abort_lock();
236
237 // first to abort ?
238 if ( !first ) {
239 // We aren't the first to abort just let C handle it
240 signal( SIGABRT, SIG_DFL ); // restore default in case we came here through the function.
241 __cabi_libc.abort();
242 }
243
244 int len = snprintf( abort_text, abort_text_size, "Cforall Runtime error (UNIX pid:%ld) ", (long int)getpid() ); // use UNIX pid (versus getPid)
245 __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
246
247 // print the cause of the error
248 assert( fmt );
249 len = vsnprintf( abort_text, abort_text_size, fmt, args );
250 __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
251
252 // add optional newline if missing at the end of the format text
253 if ( fmt[strlen( fmt ) - 1] != '\n' ) {
254 __cfaabi_bits_write( STDERR_FILENO, "\n", 1 );
255 } // if
256
257 // Give the kernel the chance to add some data in here
258 __kernel_abort_msg( abort_text, abort_text_size );
259
260 // print stack trace in handler
261 __cfaabi_backtrace( signalAbort ? 4 : 2 );
262
263 // Finally call abort
264 __cabi_libc.abort();
265
266}
267
268void abort( const char fmt[], ... ) {
269 va_list args;
270 va_start( args, fmt );
271 __abort( false, fmt, args );
272 // CONTROL NEVER REACHES HERE!
273 va_end( args );
274}
275
276void abort( bool signalAbort, const char fmt[], ... ) {
277 va_list args;
278 va_start( args, fmt );
279 __abort( signalAbort, fmt, args );
280 // CONTROL NEVER REACHES HERE!
281 va_end( args );
282}
283
284void sigHandler_segv( __CFA_SIGPARMS__ ) {
285 if ( sfp->si_addr == 0p ) {
286 abort( true, "Null pointer (0p) dereference.\n" );
287 } else {
288 abort( true, "%s at memory location %p.\n"
289 "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",
290 (sig == SIGSEGV ? "Segment fault" : "Bus error"), sfp->si_addr );
291 }
292}
293
294void sigHandler_ill( __CFA_SIGPARMS__ ) {
295 abort( true, "Executing illegal instruction at location %p.\n"
296 "Possible cause is stack corruption.\n",
297 sfp->si_addr );
298}
299
300void sigHandler_fpe( __CFA_SIGPARMS__ ) {
301 const char * msg;
302
303 choose( sfp->si_code ) {
304 case FPE_INTDIV, FPE_FLTDIV: msg = "divide by zero";
305 case FPE_FLTOVF: msg = "overflow";
306 case FPE_FLTUND: msg = "underflow";
307 case FPE_FLTRES: msg = "inexact result";
308 case FPE_FLTINV: msg = "invalid operation";
309 default: msg = "unknown";
310 } // choose
311 abort( true, "Computation error %s at location %p.\n", msg, sfp->si_addr );
312}
313
314void sigHandler_term( __CFA_SIGPARMS__ ) {
315 abort( true, "Application interrupted by signal: %s.\n", strsignal( sig ) );
316}
317
318// Local Variables: //
319// mode: c //
320// tab-width: 4 //
321// End: //
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