3 /* ex - Exception Handling (modified to fit into SimGrid from OSSP version) */
5 /* Copyright (c) 2005, 2006, 2007 Martin Quinson */
6 /* Copyright (c) 2002-2004 Ralf S. Engelschall <rse@engelschall.com> */
7 /* Copyright (c) 2002-2004 The OSSP Project <http://www.ossp.org/> */
8 /* Copyright (c) 2002-2004 Cable & Wireless <http://www.cw.com/> */
9 /* All rights reserved. */
11 /* This program is free software; you can redistribute it and/or modify it
12 * under the terms of the license (GNU LGPL) which comes with this package. */
17 #include "portable.h" /* execinfo when available */
19 #include "xbt/module.h" /* xbt_binary_name */
21 #include "gras/Virtu/virtu_interface.h" /* gras_os_myname */
22 #include "xbt/ex_interface.h"
24 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_ex,xbt,"Exception mecanism");
26 /* default __ex_ctx callback function */
27 ex_ctx_t *__xbt_ex_ctx_default(void) {
28 static ex_ctx_t ctx = XBT_CTX_INITIALIZER;
33 /* Change raw libc symbols to file names and line numbers */
34 void xbt_ex_setup_backtrace(xbt_ex_t *e);
36 void xbt_backtrace_current(xbt_ex_t *e) {
37 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
38 e->used = backtrace((void**)e->bt,XBT_BACKTRACE_SIZE);
40 xbt_ex_setup_backtrace(e);
44 void xbt_backtrace_display(xbt_ex_t *e) {
45 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
49 fprintf(stderr,"(backtrace not set)\n");
51 fprintf(stderr,"Backtrace:\n");
52 for (i=1; i<e->used; i++) /* no need to display "xbt_display_backtrace" */
53 fprintf(stderr,"---> %s\n",e->bt_strings[i] +4);
56 /* don't fool xbt_ex_free with uninitialized msg field */
61 ERROR0("No backtrace on this arch");
65 /** \brief show the backtrace of the current point (lovely while debuging) */
66 void xbt_backtrace_display_current(void) {
68 xbt_backtrace_current(&e);
69 xbt_backtrace_display(&e);
72 extern char **environ; /* the environment, as specified by the opengroup */
74 void xbt_ex_setup_backtrace(xbt_ex_t *e) {
75 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
77 /* to get the backtrace from the libc */
78 char **backtrace = backtrace_symbols (e->bt, e->used);
80 /* To build the commandline of addr2line */
83 /* to extract the addresses from the backtrace */
84 char **addrs=xbt_new(char*,e->used);
87 /* To read the output of addr2line */
89 char line_func[1024],line_pos[1024];
91 /* size (in char) of pointers on this arch */
94 /* To search for the right executable path when not trivial */
96 char *binary_name = NULL;
98 /* Some arches only have stubs of backtrace, no implementation (hppa comes to mind) */
102 /* build the commandline */
103 if (stat(xbt_binary_name,&stat_buf)) {
104 /* Damn. binary not in current dir. We'll have to dig the PATH to find it */
106 for (i=0; environ[i]; i++) {
107 if (!strncmp("PATH=",environ[i], 5)) {
108 xbt_dynar_t path=xbt_str_split(environ[i] + 5, ":");
111 xbt_dynar_foreach(path, cpt, data) {
114 binary_name = bprintf("%s/%s",data,xbt_binary_name);
115 if (!stat(binary_name,&stat_buf)) {
117 DEBUG1("Looked in the PATH for the binary. Found %s",binary_name);
118 xbt_dynar_free(&path);
122 if (stat(binary_name,&stat_buf)) {
125 e->bt_strings = xbt_new(char*,1);
126 e->bt_strings[0] = bprintf("(binary '%s' not found the path)",xbt_binary_name);
129 xbt_dynar_free(&path);
134 binary_name = xbt_strdup(xbt_binary_name);
136 cmd = curr = xbt_new(char,strlen(ADDR2LINE)+25+strlen(binary_name)+32*e->used);
138 curr += sprintf(curr,"%s -f -e %s ",ADDR2LINE,binary_name);
141 for (i=0; i<e->used;i++) {
142 /* retrieve this address */
143 DEBUG2("Retrieving address number %d from '%s'", i, backtrace[i]);
144 snprintf(buff,256,"%s",strchr(backtrace[i],'[')+1);
147 if (strcmp(buff,"(nil)"))
148 addrs[i]=bprintf("%s", buff);
150 addrs[i]=bprintf("0x0");
151 DEBUG3("Set up a new address: %d, '%s'(%p)", i, addrs[i], addrs[i]);
153 /* Add it to the command line args */
154 curr+=sprintf(curr,"%s ",addrs[i]);
156 addr_len = strlen(addrs[0]);
158 /* parse the output and build a new backtrace */
159 e->bt_strings = xbt_new(char*,e->used);
161 VERB1("Fire a first command: '%s'", cmd);
162 pipe = popen(cmd, "r");
164 CRITICAL0("Cannot fork addr2line to display the backtrace");
168 for (i=0; i<e->used; i++) {
169 DEBUG2("Looking for symbol %d, addr = '%s'", i, addrs[i]);
170 fgets(line_func,1024,pipe);
171 line_func[strlen(line_func)-1]='\0';
172 fgets(line_pos,1024,pipe);
173 line_pos[strlen(line_pos)-1]='\0';
175 if (strcmp("??",line_func)) {
176 DEBUG2("Found static symbol %s() at %s", line_func, line_pos);
177 e->bt_strings[i] = bprintf("** In %s() at %s", line_func,line_pos);
179 /* Damn. The symbol is in a dynamic library. Let's get wild */
184 long int addr,offset=0;
191 /* let's look for the offset of this library in our addressing space */
192 maps_name=bprintf("/proc/%d/maps",(int)getpid());
193 maps=fopen(maps_name,"r");
195 sscanf(addrs[i],"%lx",&addr);
196 sprintf(maps_buff,"%#lx",addr);
198 if (strcmp(addrs[i],maps_buff)) {
199 CRITICAL2("Cannot parse backtrace address '%s' (addr=%#lx)",
202 DEBUG2("addr=%s (as string) =%#lx (as number)",addrs[i],addr);
205 long int first, last;
206 if (fgets(maps_buff,512,maps) == NULL)
209 maps_buff[strlen(maps_buff) -1]='\0';
210 DEBUG1("map line: %s", maps_buff);
212 sscanf(maps_buff,"%lx",&first);
213 p=strchr(maps_buff,'-')+1;
214 sscanf(p,"%lx",&last);
215 if (first < addr && addr < last) {
220 DEBUG3("%#lx in [%#lx-%#lx]", addr, first,last);
221 DEBUG0("Symbol found, map lines not further displayed (even if looking for next ones)");
228 VERB0("Problem while reading the maps file. Following backtrace will be mangled.");
229 DEBUG1("No dynamic. Static symbol: %s", backtrace[i]);
230 e->bt_strings[i] = bprintf("** In ?? (%s)", backtrace[i]);
234 /* Ok, Found the offset of the maps line containing the searched symbol.
235 We now need to substract this from the address we got from backtrace.
239 addrs[i] = bprintf("0x%0*lx",addr_len-2,addr-offset);
240 DEBUG2("offset=%#lx new addr=%s",offset,addrs[i]);
242 /* Got it. We have our new address. Let's get the library path and we
244 p = xbt_strdup(backtrace[i]);
246 /* library path not displayed in the map file either... */
248 sprintf(line_func,"??");
255 /* Here we go, fire an addr2line up */
256 subcmd = bprintf("%s -f -e %s %s",ADDR2LINE,p, addrs[i]);
258 VERB1("Fire a new command: '%s'",subcmd);
259 subpipe = popen(subcmd,"r");
261 CRITICAL0("Cannot fork addr2line to display the backtrace");
264 fgets(line_func,1024,subpipe);
265 line_func[strlen(line_func)-1]='\0';
266 fgets(line_pos,1024,subpipe);
267 line_pos[strlen(line_pos)-1]='\0';
272 /* check whether the trick worked */
273 if (strcmp("??",line_func)) {
274 DEBUG2("Found dynamic symbol %s() at %s", line_func, line_pos);
275 e->bt_strings[i] = bprintf("** In %s() at %s", line_func,line_pos);
277 /* damn, nothing to do here. Let's print the raw address */
278 DEBUG1("Dynamic symbol not found. Raw address = %s", backtrace[i]);
279 e->bt_strings[i] = bprintf("** In ?? at %s", backtrace[i]);
285 /* Mask the bottom of the stack */
286 if (!strncmp("main",line_func,strlen("main"))) {
288 for (j=i+1; j<e->used; j++)
293 if (!strncmp("__context_wrapper",line_func,strlen("__context_wrapper"))) {
295 for (j=i+1; j<e->used; j++)
309 /** @brief shows an exception content and the associated stack if available */
310 void xbt_ex_display(xbt_ex_t *e) {
314 bprintf(" on host %s(%d)",e->host,e->pid);
317 "** SimGrid: UNCAUGHT EXCEPTION received on %s(%d): category: %s; value: %d\n"
319 "** Thrown by %s()%s\n",
320 gras_os_myname(),(*xbt_getpid)(),
321 xbt_ex_catname(e->category), e->value, e->msg,
322 e->procname,thrower?thrower:" in this process");
323 CRITICAL1("%s",e->msg);
328 if (!e->remote && !e->bt_strings)
329 xbt_ex_setup_backtrace(e);
331 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
332 /* We have everything to build neat backtraces */
336 fprintf(stderr,"\n");
337 for (i=0; i<e->used; i++)
338 fprintf(stderr,"%s\n",e->bt_strings[i]);
342 fprintf(stderr," at %s:%d:%s (no backtrace available on that arch)\n",
343 e->file,e->line,e->func);
349 /* default __ex_terminate callback function */
350 void __xbt_ex_terminate_default(xbt_ex_t *e) {
356 /* the externally visible API */
357 XBT_PUBLIC_DATA(ex_ctx_cb_t) __xbt_ex_ctx = &__xbt_ex_ctx_default;
358 XBT_PUBLIC_DATA(ex_term_cb_t) __xbt_ex_terminate = &__xbt_ex_terminate_default;
361 void xbt_ex_free(xbt_ex_t e) {
364 if (e.msg) free(e.msg);
373 for (i=0; i<e.used; i++)
374 free((char*)e.bt_strings[i]);
375 free((char **)e.bt_strings);
377 /* memset(e,0,sizeof(xbt_ex_t)); */
380 /** \brief returns a short name for the given exception category */
381 const char * xbt_ex_catname(xbt_errcat_t cat) {
383 case unknown_error: return "unknown_err";
384 case arg_error: return "invalid_arg";
385 case mismatch_error: return "mismatch";
386 case not_found_error: return "not found";
387 case system_error: return "system_err";
388 case network_error: return "network_err";
389 case timeout_error: return "timeout";
390 case thread_error: return "thread_err";
391 default: return "INVALID_ERR";
395 #ifndef HAVE_EXECINFO_H
396 /* dummy implementation. We won't use the result, but ex.h needs it to be defined */
397 int backtrace (void **__array, int __size) {
407 XBT_TEST_SUITE("xbt_ex","Exception Handling");
409 XBT_TEST_UNIT("controlflow",test_controlflow, "basic nested control flow") {
413 xbt_test_add0("basic nested control flow");
417 xbt_test_fail1("M1: n=%d (!= 1)", n);
421 xbt_test_fail1("M2: n=%d (!= 2)", n);
423 THROW0(unknown_error,0,"something");
426 xbt_test_fail1("M3: n=%d (!= 3)", n);
433 xbt_test_fail1("M2: n=%d (!= 5)", n);
435 THROW0(unknown_error,0,"something");
438 xbt_test_fail1("M3: n=%d (!= 6)", n);
443 xbt_test_fail1("MX: n=%d (shouldn't reach this point)", n);
447 xbt_test_fail1("M4: n=%d (!= 7)", n);
452 xbt_test_fail1("M5: n=%d (!= 8)", n);
455 XBT_TEST_UNIT("value",test_value,"exception value passing") {
459 THROW0(unknown_error, 2, "toto");
461 xbt_test_add0("exception value passing");
462 if (ex.category != unknown_error)
463 xbt_test_fail1("category=%d (!= 1)", ex.category);
465 xbt_test_fail1("value=%d (!= 2)", ex.value);
466 if (strcmp(ex.msg,"toto"))
467 xbt_test_fail1("message=%s (!= toto)", ex.msg);
472 XBT_TEST_UNIT("variables",test_variables,"variable value preservation") {
477 r1 = r2 = v1 = v2 = 1234;
481 THROW0(unknown_error, 0, "toto");
483 xbt_test_add0("variable preservation");
485 xbt_test_fail1("r1=%d (!= 1234)", r1);
487 xbt_test_fail1("v1=%d (!= 1234)", v1);
488 /* r2 is allowed to be destroyed because not volatile */
490 xbt_test_fail1("v2=%d (!= 5678)", v2);
495 XBT_TEST_UNIT("cleanup",test_cleanup,"cleanup handling") {
500 xbt_test_add0("cleanup handling");
506 THROW0(1, 2, "blah");
509 xbt_test_fail1("v1 = %d (!= 5678)", v1);
513 xbt_test_fail1("v1 = %d (!= 5678)", v1);
514 if (!(ex.category == 1 && ex.value == 2 && !strcmp(ex.msg,"blah")))
515 xbt_test_fail0("unexpected exception contents");
519 xbt_test_fail0("xbt_ex_free not executed");
524 * The following is the example included in the documentation. It's a good
525 * idea to check its syntax even if we don't try to run it.
526 * And actually, it allows to put comments in the code despite doxygen.
528 static char *mallocex(int size) {
531 #define SMALLAMOUNT 10
532 #define TOOBIG 100000000
534 #if 0 /* this contains syntax errors, actually */
535 static void bad_example(void) {
536 struct {char*first;} *globalcontext;
541 char *cp1, *cp2, *cp3;
543 cp1 = mallocex(SMALLAMOUNT);
544 globalcontext->first = cp1;
545 cp2 = mallocex(TOOBIG);
546 cp3 = mallocex(SMALLAMOUNT);
550 if (cp3 != NULL) free(cp3);
551 if (cp2 != NULL) free(cp2);
552 if (cp1 != NULL) free(cp1);
554 printf("cp3=%s", cp3);
557 /* end_of_bad_example */
560 typedef struct {char *first;} global_context_t;
562 static void good_example(void) {
563 global_context_t *global_context=malloc(sizeof(global_context_t));
568 char * volatile /*03*/ cp1 = NULL /*02*/;
569 char * volatile /*03*/ cp2 = NULL /*02*/;
570 char * volatile /*03*/ cp3 = NULL /*02*/;
572 cp1 = mallocex(SMALLAMOUNT);
573 global_context->first = cp1;
574 cp1 = NULL /*05 give away*/;
575 cp2 = mallocex(TOOBIG);
576 cp3 = mallocex(SMALLAMOUNT);
580 printf("cp3=%s", cp3 == NULL /*02*/ ? "" : cp3);
585 /*05 cp1 was given away */
587 /*05 global context untouched */
591 /* end_of_good_example */
593 #endif /* SIMGRID_TEST */