3 /* ex - Exception Handling (modified to fit into SimGrid from OSSP version) */
5 /* Copyright (c) 2005-2006 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 */
20 #include "xbt/ex_interface.h"
22 #include "gras/Virtu/virtu_interface.h" /* gras_os_myname */
24 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_ex,xbt,"Exception mecanism");
27 /* default __ex_ctx callback function */
28 ex_ctx_t *__xbt_ex_ctx_default(void) {
29 static ex_ctx_t ctx = XBT_CTX_INITIALIZER;
35 /** \brief show the backtrace of the current point (lovely while debuging) */
36 void xbt_backtrace_display(void) {
37 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
41 e.used = backtrace((void**)e.bt,XBT_BACKTRACE_SIZE);
43 xbt_ex_setup_backtrace(&e);
44 for (i=1; i<e.used; i++) /* no need to display "xbt_display_backtrace" */
45 fprintf(stderr,"%s\n",e.bt_strings[i]);
51 ERROR0("No backtrace on this arch");
55 extern char **environ; /* the environment, as specified by the opengroup */
57 void xbt_ex_setup_backtrace(xbt_ex_t *e) {
58 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
60 /* to get the backtrace from the libc */
61 char **backtrace = backtrace_symbols (e->bt, e->used);
63 /* To build the commandline of addr2line */
66 /* to extract the addresses from the backtrace */
67 char **addrs=xbt_new(char*,e->used);
70 /* To read the output of addr2line */
72 char line_func[1024],line_pos[1024];
74 /* size (in char) of pointers on this arch */
77 /* To search for the right executable path when not trivial */
79 char *binary_name = NULL;
81 /* Some arches only have stubs of backtrace, no implementation (hppa comes to mind) */
85 /* build the commandline */
86 if (stat(xbt_binary_name,&stat_buf)) {
87 /* Damn. binary not in current dir. We'll have to dig the PATH to find it */
89 for (i=0; environ[i]; i++) {
90 if (!strncmp("PATH=",environ[i], 5)) {
91 xbt_dynar_t path=xbt_str_split(environ[i] + 5, ":");
94 xbt_dynar_foreach(path, cpt, data) {
97 binary_name = bprintf("%s/%s",data,xbt_binary_name);
98 if (!stat(binary_name,&stat_buf)) {
100 DEBUG1("Looked in the PATH for the binary. Found %s",binary_name);
101 xbt_dynar_free(&path);
105 if (stat(binary_name,&stat_buf)) {
108 e->bt_strings = xbt_new(char*,1);
109 e->bt_strings[0] = bprintf("(binary '%s' not found the path)",xbt_binary_name);
112 xbt_dynar_free(&path);
117 binary_name = xbt_strdup(xbt_binary_name);
119 cmd = curr = xbt_new(char,strlen(ADDR2LINE)+25+strlen(binary_name)+32*e->used);
121 curr += sprintf(curr,"%s -f -e %s ",ADDR2LINE,binary_name);
124 for (i=0; i<e->used;i++) {
125 /* retrieve this address */
126 DEBUG2("Retrieving address number %d from '%s'", i, backtrace[i]);
127 snprintf(buff,256,"%s",strchr(backtrace[i],'[')+1);
130 if (strcmp(buff,"(nil)"))
131 addrs[i]=bprintf("%s", buff);
133 addrs[i]=bprintf("0x0");
134 DEBUG3("Set up a new address: %d, '%s'(%p)", i, addrs[i], addrs[i]);
136 /* Add it to the command line args */
137 curr+=sprintf(curr,"%s ",addrs[i]);
139 addr_len = strlen(addrs[0]);
141 /* parse the output and build a new backtrace */
142 e->bt_strings = xbt_new(char*,e->used);
144 VERB1("Fire a first command: '%s'", cmd);
145 pipe = popen(cmd, "r");
147 CRITICAL0("Cannot fork addr2line to display the backtrace");
151 for (i=0; i<e->used; i++) {
152 DEBUG2("Looking for symbol %d, addr = '%s'", i, addrs[i]);
153 fgets(line_func,1024,pipe);
154 line_func[strlen(line_func)-1]='\0';
155 fgets(line_pos,1024,pipe);
156 line_pos[strlen(line_pos)-1]='\0';
158 if (strcmp("??",line_func)) {
159 DEBUG2("Found static symbol %s() at %s", line_func, line_pos);
160 e->bt_strings[i] = bprintf("** In %s() at %s", line_func,line_pos);
162 /* Damn. The symbol is in a dynamic library. Let's get wild */
167 long int addr,offset=0;
174 /* let's look for the offset of this library in our addressing space */
175 maps_name=bprintf("/proc/%d/maps",(int)getpid());
176 maps=fopen(maps_name,"r");
178 sscanf(addrs[i],"%lx",&addr);
179 sprintf(maps_buff,"%#lx",addr);
181 if (strcmp(addrs[i],maps_buff)) {
182 CRITICAL2("Cannot parse backtrace address '%s' (addr=%#lx)",
185 DEBUG2("addr=%s (as string) =%#lx (as number)",addrs[i],addr);
188 long int first, last;
189 if (fgets(maps_buff,512,maps) == NULL)
192 maps_buff[strlen(maps_buff) -1]='\0';
193 DEBUG1("map line: %s", maps_buff);
195 sscanf(maps_buff,"%lx",&first);
196 p=strchr(maps_buff,'-')+1;
197 sscanf(p,"%lx",&last);
198 if (first < addr && addr < last) {
203 DEBUG3("%#lx in [%#lx-%#lx]", addr, first,last);
204 DEBUG0("Symbol found, map lines not further displayed (even if looking for next ones)");
211 VERB0("Problem while reading the maps file. Following backtrace will be mangled.");
212 DEBUG1("No dynamic. Static symbol: %s", backtrace[i]);
213 e->bt_strings[i] = bprintf("** In ?? (%s)", backtrace[i]);
217 /* Ok, Found the offset of the maps line containing the searched symbol.
218 We now need to substract this from the address we got from backtrace.
222 addrs[i] = bprintf("0x%0*lx",addr_len-2,addr-offset);
223 DEBUG2("offset=%#lx new addr=%s",offset,addrs[i]);
225 /* Got it. We have our new address. Let's get the library path and we
227 p = xbt_strdup(backtrace[i]);
229 /* library path not displayed in the map file either... */
231 sprintf(line_func,"??");
238 /* Here we go, fire an addr2line up */
239 subcmd = bprintf("%s -f -e %s %s",ADDR2LINE,p, addrs[i]);
241 VERB1("Fire a new command: '%s'",subcmd);
242 subpipe = popen(subcmd,"r");
244 CRITICAL0("Cannot fork addr2line to display the backtrace");
247 fgets(line_func,1024,subpipe);
248 line_func[strlen(line_func)-1]='\0';
249 fgets(line_pos,1024,subpipe);
250 line_pos[strlen(line_pos)-1]='\0';
255 /* check whether the trick worked */
256 if (strcmp("??",line_func)) {
257 DEBUG2("Found dynamic symbol %s() at %s", line_func, line_pos);
258 e->bt_strings[i] = bprintf("** In %s() at %s", line_func,line_pos);
260 /* damn, nothing to do here. Let's print the raw address */
261 DEBUG1("Dynamic symbol not found. Raw address = %s", backtrace[i]);
262 e->bt_strings[i] = bprintf("** In ?? at %s", backtrace[i]);
268 /* Mask the bottom of the stack */
269 if (!strncmp("main",line_func,strlen("main"))) {
271 for (j=i+1; j<e->used; j++)
276 if (!strncmp("__context_wrapper",line_func,strlen("__context_wrapper"))) {
278 for (j=i+1; j<e->used; j++)
292 /** @brief shows an exception content and the associated stack if available */
293 void xbt_ex_display(xbt_ex_t *e) {
297 bprintf(" on host %s(%d)",e->host,e->pid);
300 "** SimGrid: UNCAUGHT EXCEPTION received on %s(%d): category: %s; value: %d\n"
302 "** Thrown by %s()%s\n",
303 gras_os_myname(),(*xbt_getpid)(),
304 xbt_ex_catname(e->category), e->value, e->msg,
305 e->procname,thrower?thrower:" in this process");
306 CRITICAL1("%s",e->msg);
311 if (!e->remote && !e->bt_strings)
312 xbt_ex_setup_backtrace(e);
314 #if defined(HAVE_EXECINFO_H) && defined(HAVE_POPEN) && defined(ADDR2LINE)
315 /* We have everything to build neat backtraces */
319 fprintf(stderr,"\n");
320 for (i=0; i<e->used; i++)
321 fprintf(stderr,"%s\n",e->bt_strings[i]);
325 fprintf(stderr," at %s:%d:%s (no backtrace available on that arch)\n",
326 e->file,e->line,e->func);
332 /* default __ex_terminate callback function */
333 void __xbt_ex_terminate_default(xbt_ex_t *e) {
339 /* the externally visible API */
340 XBT_PUBLIC_DATA(ex_ctx_cb_t) __xbt_ex_ctx = &__xbt_ex_ctx_default;
341 XBT_PUBLIC_DATA(ex_term_cb_t) __xbt_ex_terminate = &__xbt_ex_terminate_default;
344 void xbt_ex_free(xbt_ex_t e) {
347 if (e.msg) free(e.msg);
356 for (i=0; i<e.used; i++)
357 free((char*)e.bt_strings[i]);
358 free((char **)e.bt_strings);
360 /* memset(e,0,sizeof(xbt_ex_t)); */
363 /** \brief returns a short name for the given exception category */
364 const char * xbt_ex_catname(xbt_errcat_t cat) {
366 case unknown_error: return "unknown_err";
367 case arg_error: return "invalid_arg";
368 case mismatch_error: return "mismatch";
369 case not_found_error: return "not found";
370 case system_error: return "system_err";
371 case network_error: return "network_err";
372 case timeout_error: return "timeout";
373 case thread_error: return "thread_err";
374 default: return "INVALID_ERR";
378 #ifndef HAVE_EXECINFO_H
379 /* dummy implementation. We won't use the result, but ex.h needs it to be defined */
380 int backtrace (void **__array, int __size) {
390 XBT_TEST_SUITE("xbt_ex","Exception Handling");
392 XBT_TEST_UNIT("controlflow",test_controlflow, "basic nested control flow") {
396 xbt_test_add0("basic nested control flow");
400 xbt_test_fail1("M1: n=%d (!= 1)", n);
404 xbt_test_fail1("M2: n=%d (!= 2)", n);
406 THROW0(unknown_error,0,"something");
409 xbt_test_fail1("M3: n=%d (!= 3)", n);
416 xbt_test_fail1("M2: n=%d (!= 5)", n);
418 THROW0(unknown_error,0,"something");
421 xbt_test_fail1("M3: n=%d (!= 6)", n);
426 xbt_test_fail1("MX: n=%d (shouldn't reach this point)", n);
430 xbt_test_fail1("M4: n=%d (!= 7)", n);
435 xbt_test_fail1("M5: n=%d (!= 8)", n);
438 XBT_TEST_UNIT("value",test_value,"exception value passing") {
442 THROW0(unknown_error, 2, "toto");
444 xbt_test_add0("exception value passing");
445 if (ex.category != unknown_error)
446 xbt_test_fail1("category=%d (!= 1)", ex.category);
448 xbt_test_fail1("value=%d (!= 2)", ex.value);
449 if (strcmp(ex.msg,"toto"))
450 xbt_test_fail1("message=%s (!= toto)", ex.msg);
455 XBT_TEST_UNIT("variables",test_variables,"variable value preservation") {
460 r1 = r2 = v1 = v2 = 1234;
464 THROW0(unknown_error, 0, "toto");
466 xbt_test_add0("variable preservation");
468 xbt_test_fail1("r1=%d (!= 1234)", r1);
470 xbt_test_fail1("v1=%d (!= 1234)", v1);
471 /* r2 is allowed to be destroyed because not volatile */
473 xbt_test_fail1("v2=%d (!= 5678)", v2);
478 XBT_TEST_UNIT("cleanup",test_cleanup,"cleanup handling") {
483 xbt_test_add0("cleanup handling");
489 THROW0(1, 2, "blah");
492 xbt_test_fail1("v1 = %d (!= 5678)", v1);
496 xbt_test_fail1("v1 = %d (!= 5678)", v1);
497 if (!(ex.category == 1 && ex.value == 2 && !strcmp(ex.msg,"blah")))
498 xbt_test_fail0("unexpected exception contents");
502 xbt_test_fail0("xbt_ex_free not executed");
507 * The following is the example included in the documentation. It's a good
508 * idea to check its syntax even if we don't try to run it.
509 * And actually, it allows to put comments in the code despite doxygen.
511 static char *mallocex(int size) {
514 #define SMALLAMOUNT 10
515 #define TOOBIG 100000000
517 #if 0 /* this contains syntax errors, actually */
518 static void bad_example(void) {
519 struct {char*first;} *globalcontext;
524 char *cp1, *cp2, *cp3;
526 cp1 = mallocex(SMALLAMOUNT);
527 globalcontext->first = cp1;
528 cp2 = mallocex(TOOBIG);
529 cp3 = mallocex(SMALLAMOUNT);
533 if (cp3 != NULL) free(cp3);
534 if (cp2 != NULL) free(cp2);
535 if (cp1 != NULL) free(cp1);
537 printf("cp3=%s", cp3);
540 /* end_of_bad_example */
543 typedef struct {char *first;} global_context_t;
545 static void good_example(void) {
546 global_context_t *global_context=malloc(sizeof(global_context_t));
551 char * volatile /*03*/ cp1 = NULL /*02*/;
552 char * volatile /*03*/ cp2 = NULL /*02*/;
553 char * volatile /*03*/ cp3 = NULL /*02*/;
555 cp1 = mallocex(SMALLAMOUNT);
556 global_context->first = cp1;
557 cp1 = NULL /*05 give away*/;
558 cp2 = mallocex(TOOBIG);
559 cp3 = mallocex(SMALLAMOUNT);
563 printf("cp3=%s", cp3 == NULL /*02*/ ? "" : cp3);
568 /*05 cp1 was given away */
570 /*05 global context untouched */
574 /* end_of_good_example */
576 #endif /* SIMGRID_TEST */