-/* $Id: ex.c 5173 2008-01-07 22:10:52Z mquinson $ */
-
/* backtrace_linux - backtrace displaying on linux platform */
/* This file is included by ex.c on need (have execinfo.h, popen & addrline)*/
-/* Copyright (c) 2007 The SimGrid team */
-/* All rights reserved. */
+/* Copyright (c) 2008, 2009, 2010. The SimGrid Team.
+ * All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-extern char **environ; /* the environment, as specified by the opengroup */
+/* This file is to be included in ex.c, so the following headers are not mandatory, but it's to make sure that eclipse see them too */
+#include "xbt/ex.h"
+#include "xbt/str.h"
+#include "xbt/module.h" /* xbt_binary_name */
+#include "xbt_modinter.h" /* backtrace initialization headers */
+/* end of "useless" inclusions */
+
+extern char **environ; /* the environment, as specified by the opengroup */
+
+/* Module creation/destruction: nothing to do on linux */
+void xbt_backtrace_preinit(void)
+{
+}
+
+void xbt_backtrace_postexit(void)
+{
+}
+
+#include <unwind.h>
+struct trace_arg {
+ void **array;
+ int cnt, size;
+};
+
+static _Unwind_Reason_Code
+backtrace_helper (struct _Unwind_Context *ctx, void *a)
+{
+ struct trace_arg *arg = a;
+
+ /* We are first called with address in the __backtrace function.
+ Skip it. */
+ if (arg->cnt != -1)
+ {
+ arg->array[arg->cnt] = (void *) _Unwind_GetIP(ctx);
+
+ /* Check whether we make any progress. */
+ if (arg->cnt > 0 && arg->array[arg->cnt - 1] == arg->array[arg->cnt])
+ return _URC_END_OF_STACK;
+ }
+ if (++arg->cnt == arg->size)
+ return _URC_END_OF_STACK;
+ return _URC_NO_REASON;
+}
+
+/** @brief reimplementation of glibc backtrace based directly on gcc library, without implicit malloc
+ *
+ * See http://webloria.loria.fr/~quinson/blog/2012/0208/system_programming_fun_in_SimGrid/
+ * for the motivation behind this function
+ * */
+
+int xbt_backtrace_no_malloc(void **array, int size) {
+
+ int i = 0;
+ for(i=0; i < size; i++)
+ array[i] = NULL;
-void xbt_ex_setup_backtrace(xbt_ex_t *e) {
+ struct trace_arg arg = { .array = array, .size = size, .cnt = -1 };
+
+ if (size >= 1)
+ _Unwind_Backtrace(backtrace_helper, &arg);
+
+ /* _Unwind_Backtrace on IA-64 seems to put NULL address above
+ _start. Fix it up here. */
+ if (arg.cnt > 1 && arg.array[arg.cnt - 1] == NULL)
+ --arg.cnt;
+ return arg.cnt != -1 ? arg.cnt : 0;
+}
+
+void xbt_backtrace_current(xbt_ex_t * e)
+{
+ e->used = backtrace((void **) e->bt, XBT_BACKTRACE_SIZE);
+ if (e->used == 0) {
+ fprintf(stderr, "The backtrace() function failed, which probably means that the memory is exhausted. Here is a crude dump of the exception that I was trying to build:");
+ fprintf(stderr, "%s:%s(%d) [%s:%d] %s", e->host,e->procname,e->pid, e->file,e->line,e->msg);
+ fprintf(stderr, "Bailing out now since there is nothing I can do without a decent amount of memory. Please go fix the memleaks\n");
+ exit(1);
+ }
+}
+
+
+void xbt_ex_setup_backtrace(xbt_ex_t * e) //FIXME: This code could be greatly improved/simplifyied with http://cairo.sourcearchive.com/documentation/1.9.4/backtrace-symbols_8c-source.html
+{
int i;
+
/* to get the backtrace from the libc */
- char **backtrace = backtrace_symbols (e->bt, e->used);
-
+ char **backtrace_syms;
+
/* To build the commandline of addr2line */
char *cmd, *curr;
-
+
/* to extract the addresses from the backtrace */
- char **addrs=xbt_new(char*,e->used);
- char buff[256],*p;
-
+ char **addrs;
+ char buff[256];
+
/* To read the output of addr2line */
FILE *pipe;
- char line_func[1024],line_pos[1024];
+ char line_func[1024], line_pos[1024];
/* size (in char) of pointers on this arch */
- int addr_len=0;
+ int addr_len = 0;
/* To search for the right executable path when not trivial */
struct stat stat_buf;
char *binary_name = NULL;
-
- /* Some arches only have stubs of backtrace, no implementation (hppa comes to mind) */
- if (!e->used)
- return;
-
+
+ xbt_assert(e, "Backtrace not setup yet, cannot set it up for display");
+
+ e->bt_strings = NULL;
+
+ if (!xbt_binary_name) /* no binary name, nothing to do */
+ return;
+
+ if (e->used <= 1)
+ return;
+
+ /* ignore first one, which is xbt_backtrace_current() */
+ e->used--;
+ memmove(e->bt, e->bt + 1, (sizeof *e->bt) * e->used);
+
+ backtrace_syms = backtrace_symbols(e->bt, e->used);
+
/* build the commandline */
- if (stat(xbt_binary_name,&stat_buf)) {
+ if (stat(xbt_binary_name, &stat_buf)) {
/* Damn. binary not in current dir. We'll have to dig the PATH to find it */
- int i;
- for (i=0; environ[i]; i++) {
- if (!strncmp("PATH=",environ[i], 5)) {
- xbt_dynar_t path=xbt_str_split(environ[i] + 5, ":");
- unsigned int cpt;
- char *data;
- xbt_dynar_foreach(path, cpt, data) {
- if (binary_name)
- free(binary_name);
- binary_name = bprintf("%s/%s",data,xbt_binary_name);
- if (!stat(binary_name,&stat_buf)) {
- /* Found. */
- DEBUG1("Looked in the PATH for the binary. Found %s",binary_name);
- xbt_dynar_free(&path);
- break;
- }
- }
- if (stat(binary_name,&stat_buf)) {
- /* not found */
- e->used = 1;
- e->bt_strings = xbt_new(char*,1);
- e->bt_strings[0] = bprintf("(binary '%s' not found the path)",xbt_binary_name);
- return;
- }
- xbt_dynar_free(&path);
- break;
- }
+ for (i = 0; environ[i]; i++) {
+ if (!strncmp("PATH=", environ[i], 5)) {
+ xbt_dynar_t path = xbt_str_split(environ[i] + 5, ":");
+ unsigned int cpt;
+ char *data;
+
+ xbt_dynar_foreach(path, cpt, data) {
+ free(binary_name);
+ binary_name = bprintf("%s/%s", data, xbt_binary_name);
+ if (!stat(binary_name, &stat_buf)) {
+ /* Found. */
+ XBT_DEBUG("Looked in the PATH for the binary. Found %s",
+ binary_name);
+ break;
+ }
+ }
+ xbt_dynar_free(&path);
+ if (stat(binary_name, &stat_buf)) {
+ /* not found */
+ e->used = 1;
+ e->bt_strings = xbt_new(char *, 1);
+
+ e->bt_strings[0] =
+ bprintf("(binary '%s' not found in the PATH)", xbt_binary_name);
+ free(backtrace_syms);
+ return;
+ }
+ break;
+ }
}
} else {
binary_name = xbt_strdup(xbt_binary_name);
- }
- cmd = curr = xbt_new(char,strlen(ADDR2LINE)+25+strlen(binary_name)+32*e->used);
-
- curr += sprintf(curr,"%s -f -e %s ",ADDR2LINE,binary_name);
+ }
+ cmd = curr =
+ xbt_new(char,
+ strlen(ADDR2LINE) + 25 + strlen(binary_name) + 32 * e->used);
+
+ curr += sprintf(curr, "%s -f -e %s ", ADDR2LINE, binary_name);
free(binary_name);
-
- for (i=0; i<e->used;i++) {
+
+ addrs = xbt_new(char *, e->used);
+ for (i = 0; i < e->used; i++) {
+ char *p;
/* retrieve this address */
- DEBUG2("Retrieving address number %d from '%s'", i, backtrace[i]);
- snprintf(buff,256,"%s",strchr(backtrace[i],'[')+1);
- p=strchr(buff,']');
- *p='\0';
- if (strcmp(buff,"(nil)"))
- addrs[i]=bprintf("%s", buff);
+ XBT_DEBUG("Retrieving address number %d from '%s'", i, backtrace_syms[i]);
+ snprintf(buff, 256, "%s", strchr(backtrace_syms[i], '[') + 1);
+ p = strchr(buff, ']');
+ *p = '\0';
+ if (strcmp(buff, "(nil)"))
+ addrs[i] = xbt_strdup(buff);
else
- addrs[i]=bprintf("0x0");
- DEBUG3("Set up a new address: %d, '%s'(%p)", i, addrs[i], addrs[i]);
-
+ addrs[i] = xbt_strdup("0x0");
+ XBT_DEBUG("Set up a new address: %d, '%s'(%p)", i, addrs[i], addrs[i]);
+
/* Add it to the command line args */
- curr+=sprintf(curr,"%s ",addrs[i]);
- }
+ curr += sprintf(curr, "%s ", addrs[i]);
+ }
addr_len = strlen(addrs[0]);
/* parse the output and build a new backtrace */
- e->bt_strings = xbt_new(char*,e->used);
-
- VERB1("Fire a first command: '%s'", cmd);
+ e->bt_strings = xbt_new(char *, e->used);
+
+ XBT_VERB("Fire a first command: '%s'", cmd);
pipe = popen(cmd, "r");
if (!pipe) {
- CRITICAL0("Cannot fork addr2line to display the backtrace");
- abort();
+ xbt_die("Cannot fork addr2line to display the backtrace");
}
- for (i=0; i<e->used; i++) {
- DEBUG2("Looking for symbol %d, addr = '%s'", i, addrs[i]);
- fgets(line_func,1024,pipe);
- line_func[strlen(line_func)-1]='\0';
- fgets(line_pos,1024,pipe);
- line_pos[strlen(line_pos)-1]='\0';
+ for (i = 0; i < e->used; i++) {
+ char *fgets_res;
+ XBT_DEBUG("Looking for symbol %d, addr = '%s'", i, addrs[i]);
+ fgets_res = fgets(line_func, 1024, pipe);
+ if (fgets_res == NULL)
+ THROWF(system_error, 0,
+ "Cannot run fgets to look for symbol %d, addr %s", i,
+ addrs[i]);
+ line_func[strlen(line_func) - 1] = '\0';
+ fgets_res = fgets(line_pos, 1024, pipe);
+ if (fgets_res == NULL)
+ THROWF(system_error, 0,
+ "Cannot run fgets to look for symbol %d, addr %s", i,
+ addrs[i]);
+ line_pos[strlen(line_pos) - 1] = '\0';
- if (strcmp("??",line_func)) {
- DEBUG2("Found static symbol %s() at %s", line_func, line_pos);
- e->bt_strings[i] = bprintf("** In %s() at %s", line_func,line_pos);
+ if (strcmp("??", line_func)) {
+ XBT_DEBUG("Found static symbol %s() at %s", line_func, line_pos);
+ e->bt_strings[i] =
+ bprintf("** In %s() at %s", line_func, line_pos);
} else {
/* Damn. The symbol is in a dynamic library. Let's get wild */
char *maps_name;
FILE *maps;
char maps_buff[512];
- long int addr,offset=0;
- char *p,*p2;
+ long int addr, offset = 0;
+ char *p, *p2;
char *subcmd;
FILE *subpipe;
- int found=0;
+ int found = 0;
/* let's look for the offset of this library in our addressing space */
- maps_name=bprintf("/proc/%d/maps",(int)getpid());
- maps=fopen(maps_name,"r");
-
- sscanf(addrs[i],"%lx",&addr);
- sprintf(maps_buff,"%#lx",addr);
-
- if (strcmp(addrs[i],maps_buff)) {
- CRITICAL2("Cannot parse backtrace address '%s' (addr=%#lx)",
- addrs[i], addr);
+ maps_name = bprintf("/proc/%d/maps", (int) getpid());
+ maps = fopen(maps_name, "r");
+
+ addr = strtol(addrs[i], &p, 16);
+ if (*p != '\0') {
+ XBT_CRITICAL("Cannot parse backtrace address '%s' (addr=%#lx)",
+ addrs[i], addr);
}
- DEBUG2("addr=%s (as string) =%#lx (as number)",addrs[i],addr);
+ XBT_DEBUG("addr=%s (as string) =%#lx (as number)", addrs[i], addr);
while (!found) {
- long int first, last;
- if (fgets(maps_buff,512,maps) == NULL)
- break;
- if (i==0) {
- maps_buff[strlen(maps_buff) -1]='\0';
- DEBUG1("map line: %s", maps_buff);
- }
- sscanf(maps_buff,"%lx",&first);
- p=strchr(maps_buff,'-')+1;
- sscanf(p,"%lx",&last);
- if (first < addr && addr < last) {
- offset = first;
- found=1;
- }
- if (found) {
- DEBUG3("%#lx in [%#lx-%#lx]", addr, first,last);
- DEBUG0("Symbol found, map lines not further displayed (even if looking for next ones)");
- }
+ long int first, last;
+
+ if (fgets(maps_buff, 512, maps) == NULL)
+ break;
+ if (i == 0) {
+ maps_buff[strlen(maps_buff) - 1] = '\0';
+ XBT_DEBUG("map line: %s", maps_buff);
+ }
+ sscanf(maps_buff, "%lx", &first);
+ p = strchr(maps_buff, '-') + 1;
+ sscanf(p, "%lx", &last);
+ if (first < addr && addr < last) {
+ offset = first;
+ found = 1;
+ }
+ if (found) {
+ XBT_DEBUG("%#lx in [%#lx-%#lx]", addr, first, last);
+ XBT_DEBUG
+ ("Symbol found, map lines not further displayed (even if looking for next ones)");
+ }
}
fclose(maps);
free(maps_name);
+ free(addrs[i]);
if (!found) {
- VERB0("Problem while reading the maps file. Following backtrace will be mangled.");
- DEBUG1("No dynamic. Static symbol: %s", backtrace[i]);
- e->bt_strings[i] = bprintf("** In ?? (%s)", backtrace[i]);
- continue;
+ XBT_VERB
+ ("Problem while reading the maps file. Following backtrace will be mangled.");
+ XBT_DEBUG("No dynamic. Static symbol: %s", backtrace_syms[i]);
+ e->bt_strings[i] = bprintf("** In ?? (%s)", backtrace_syms[i]);
+ continue;
}
- /* Ok, Found the offset of the maps line containing the searched symbol.
- We now need to substract this from the address we got from backtrace.
- */
-
- free(addrs[i]);
- addrs[i] = bprintf("0x%0*lx",addr_len-2,addr-offset);
- DEBUG2("offset=%#lx new addr=%s",offset,addrs[i]);
-
- /* Got it. We have our new address. Let's get the library path and we
- are set */
- p = xbt_strdup(backtrace[i]);
- if (p[0]=='[') {
- /* library path not displayed in the map file either... */
- free(p);
- sprintf(line_func,"??");
+ /* Ok, Found the offset of the maps line containing the searched symbol.
+ We now need to substract this from the address we got from backtrace.
+ */
+
+ addrs[i] = bprintf("0x%0*lx", addr_len - 2, addr - offset);
+ XBT_DEBUG("offset=%#lx new addr=%s", offset, addrs[i]);
+
+ /* Got it. We have our new address. Let's get the library path and we
+ are set */
+ p = xbt_strdup(backtrace_syms[i]);
+ if (p[0] == '[') {
+ /* library path not displayed in the map file either... */
+ free(p);
+ sprintf(line_func, "??");
} else {
- p2 = strrchr(p,'(');
- if (p2) *p2= '\0';
- p2 = strrchr(p,' ');
- if(p2) *p2= '\0';
-
- /* Here we go, fire an addr2line up */
- subcmd = bprintf("%s -f -e %s %s",ADDR2LINE,p, addrs[i]);
- free(p);
- VERB1("Fire a new command: '%s'",subcmd);
- subpipe = popen(subcmd,"r");
- if (!subpipe) {
- CRITICAL0("Cannot fork addr2line to display the backtrace");
- abort();
- }
- fgets(line_func,1024,subpipe);
- line_func[strlen(line_func)-1]='\0';
- fgets(line_pos,1024,subpipe);
- line_pos[strlen(line_pos)-1]='\0';
- pclose(subpipe);
- free(subcmd);
+ p2 = strrchr(p, '(');
+ if (p2)
+ *p2 = '\0';
+ p2 = strrchr(p, ' ');
+ if (p2)
+ *p2 = '\0';
+
+ /* Here we go, fire an addr2line up */
+ subcmd = bprintf("%s -f -e %s %s", ADDR2LINE, p, addrs[i]);
+ free(p);
+ XBT_VERB("Fire a new command: '%s'", subcmd);
+ subpipe = popen(subcmd, "r");
+ if (!subpipe) {
+ xbt_die("Cannot fork addr2line to display the backtrace");
+ }
+ fgets_res = fgets(line_func, 1024, subpipe);
+ if (fgets_res == NULL)
+ THROWF(system_error, 0, "Cannot read result of subcommand %s",
+ subcmd);
+ line_func[strlen(line_func) - 1] = '\0';
+ fgets_res = fgets(line_pos, 1024, subpipe);
+ if (fgets_res == NULL)
+ THROWF(system_error, 0, "Cannot read result of subcommand %s",
+ subcmd);
+ line_pos[strlen(line_pos) - 1] = '\0';
+ pclose(subpipe);
+ free(subcmd);
}
/* check whether the trick worked */
- if (strcmp("??",line_func)) {
- DEBUG2("Found dynamic symbol %s() at %s", line_func, line_pos);
- e->bt_strings[i] = bprintf("** In %s() at %s", line_func,line_pos);
+ if (strcmp("??", line_func)) {
+ XBT_DEBUG("Found dynamic symbol %s() at %s", line_func, line_pos);
+ e->bt_strings[i] =
+ bprintf("** In %s() at %s", line_func, line_pos);
} else {
- /* damn, nothing to do here. Let's print the raw address */
- DEBUG1("Dynamic symbol not found. Raw address = %s", backtrace[i]);
- e->bt_strings[i] = bprintf("** In ?? at %s", backtrace[i]);
+ /* damn, nothing to do here. Let's print the raw address */
+ XBT_DEBUG("Dynamic symbol not found. Raw address = %s",
+ backtrace_syms[i]);
+ e->bt_strings[i] = bprintf("** In ?? at %s", backtrace_syms[i]);
}
-
+
}
free(addrs[i]);
-
- /* Mask the bottom of the stack */
- if (!strncmp("main",line_func,strlen("main")) ||
- !strncmp("xbt_thread_context_wrapper",line_func,strlen("xbt_thread_context_wrapper"))) {
- int j;
- for (j=i+1; j<e->used; j++)
- free(addrs[j]);
- e->used = i;
-
- if (!strncmp("xbt_thread_context_wrapper",line_func,strlen("xbt_thread_context_wrapper"))) {
- e->used++;
- e->bt_strings[i] = bprintf("** (in a separate thread)");
- }
+
+ /* Mask the bottom of the stack */
+ if (!strncmp("main", line_func, strlen("main")) ||
+ !strncmp("xbt_thread_context_wrapper", line_func,
+ strlen("xbt_thread_context_wrapper"))
+ || !strncmp("smx_ctx_sysv_wrapper", line_func,
+ strlen("smx_ctx_sysv_wrapper"))) {
+ int j;
+
+ for (j = i + 1; j < e->used; j++)
+ free(addrs[j]);
+ e->used = i + 1;
+
+ if (!strncmp
+ ("xbt_thread_context_wrapper", line_func,
+ strlen("xbt_thread_context_wrapper"))) {
+ free(e->bt_strings[i]);
+ e->bt_strings[i] = xbt_strdup("** (in a separate thread)");
+ }
}
-
-
+
+
}
pclose(pipe);
free(addrs);
- free(backtrace);
+ free(backtrace_syms);
free(cmd);
}
