-/* $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. */
#include "xbt/str.h"
#include "xbt/module.h" /* xbt_binary_name */
#include "xbt_modinter.h" /* backtrace initialization headers */
+#include <libunwind.h>
/* 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_init(void)
+void xbt_backtrace_preinit(void)
{
}
-void xbt_backtrace_exit(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;
+
+ 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(%d) [%s:%d] %s",
+ 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)
+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 extract the addresses from the backtrace */
char **addrs;
- char buff[256], *p;
+ char buff[256];
/* To read the output of addr2line */
FILE *pipe;
struct stat stat_buf;
char *binary_name = NULL;
- xbt_assert0(e
- && e->used,
- "Backtrace not setup yet, cannot set it up for display");
-
- backtrace_syms = backtrace_symbols(e->bt, e->used);
- /* ignore first one, which is this xbt_backtrace_current() */
- e->used--;
- memmove(backtrace_syms, backtrace_syms + 1, sizeof(char *) * e->used);
- addrs = xbt_new(char *, e->used);
+ xbt_assert(e, "Backtrace not setup yet, cannot set it up for display");
e->bt_strings = NULL;
- /* Some arches only have stubs of backtrace, no implementation (hppa comes to mind) */
- if (!e->used)
+ if (xbt_binary_name == NULL) /* 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)) {
/* 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, ":");
char *data;
xbt_dynar_foreach(path, cpt, data) {
- if (binary_name)
- free(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",
+ XBT_DEBUG("Looked in the PATH for the binary. Found %s",
binary_name);
- xbt_dynar_free(&path);
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 the path)", xbt_binary_name);
+ bprintf("(binary '%s' not found in the PATH)", xbt_binary_name);
+ free(backtrace_syms);
return;
}
- xbt_dynar_free(&path);
break;
}
}
binary_name = xbt_strdup(xbt_binary_name);
}
cmd = curr =
- xbt_new(char,
- strlen(ADDR2LINE) + 25 + strlen(binary_name) + 32 * e->used);
+ 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);
+ 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_syms[i]);
+ 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] = bprintf("%s", buff);
+ 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]);
/* parse the output and build a new backtrace */
e->bt_strings = xbt_new(char *, e->used);
- VERB1("Fire a first command: '%s'", cmd);
+ 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++) {
- char *fgets_res;
- DEBUG2("Looking for symbol %d, addr = '%s'", i, addrs[i]);
- fgets_res = fgets(line_func, 1024, pipe);
- if (fgets_res == NULL)
- THROW2(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)
- THROW2(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);
+ XBT_DEBUG("Looking for symbol %d, addr = '%s'", i, addrs[i]);
+ if (fgets(line_func, 1024, pipe)) {
+ line_func[strlen(line_func) - 1] = '\0';
+ } else {
+ XBT_VERB("Cannot run fgets to look for symbol %d, addr %s", i, addrs[i]);
+ strcpy(line_func, "???");
+ }
+ if (fgets(line_pos, 1024, pipe)) {
+ line_pos[strlen(line_pos) - 1] = '\0';
+ } else {
+ XBT_VERB("Cannot run fgets to look for symbol %d, addr %s", i, addrs[i]);
+ strcpy(line_pos, backtrace_syms[i]);
+ }
+
+ if (strcmp("??", line_func) != 0) {
+ 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;
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)",
+ 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;
break;
if (i == 0) {
maps_buff[strlen(maps_buff) - 1] = '\0';
- DEBUG1("map line: %s", maps_buff);
+ XBT_DEBUG("map line: %s", maps_buff);
}
sscanf(maps_buff, "%lx", &first);
p = strchr(maps_buff, '-') + 1;
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)");
+ 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_syms[i]);
+ 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;
}
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]);
+ 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 */
/* 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);
+ XBT_VERB("Fire a new command: '%s'", subcmd);
subpipe = popen(subcmd, "r");
if (!subpipe) {
- CRITICAL0("Cannot fork addr2line to display the backtrace");
- abort();
+ xbt_die("Cannot fork addr2line to display the backtrace");
+ }
+ if (fgets(line_func, 1024, subpipe)) {
+ line_func[strlen(line_func) - 1] = '\0';
+ } else {
+ XBT_VERB("Cannot read result of subcommand %s", subcmd);
+ strcpy(line_func, "???");
+ }
+ if (fgets(line_pos, 1024, subpipe)) {
+ line_pos[strlen(line_pos) - 1] = '\0';
+ } else {
+ XBT_VERB("Cannot read result of subcommand %s", subcmd);
+ strcpy(line_pos, backtrace_syms[i]);
}
- fgets_res = fgets(line_func, 1024, subpipe);
- if (fgets_res == NULL)
- THROW1(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)
- THROW1(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);
+ 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",
+ XBT_DEBUG("Dynamic symbol not found. Raw address = %s",
backtrace_syms[i]);
e->bt_strings[i] = bprintf("** In ?? at %s", backtrace_syms[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"))) {
+ 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;
+ e->used = i + 1;
if (!strncmp
("xbt_thread_context_wrapper", line_func,
strlen("xbt_thread_context_wrapper"))) {
- e->used++;
- e->bt_strings[i] = bprintf("** (in a separate thread)");
+ free(e->bt_strings[i]);
+ e->bt_strings[i] = xbt_strdup("** (in a separate thread)");
}
}
free(backtrace_syms);
free(cmd);
}
+
+int xbt_libunwind_backtrace(void* bt[XBT_BACKTRACE_SIZE], int size){
+
+ int i = 0;
+ for(i=0; i < size; i++)
+ bt[i] = NULL;
+
+ i=0;
+
+ unw_cursor_t c;
+ unw_context_t uc;
+
+ unw_getcontext (&uc);
+ unw_init_local (&c, &uc);
+
+ unw_word_t ip;
+
+ unw_step(&c);
+
+ while(unw_step(&c) >= 0 && i < size){
+
+ unw_get_reg(&c, UNW_REG_IP, &ip);
+ bt[i] = (void*)(long)ip;
+ i++;
+
+ }
+
+ return i;
+
+}
