- int i;
- /* to get the backtrace from the libc */
- char **backtrace = backtrace_symbols (e->bt, e->used);
-
- /* To build the commandline of addr2line */
- char *cmd = xbt_new(char,strlen(ADDR2LINE)+strlen(xbt_binary_name)+20*e->used);
- char *curr=cmd;
-
- /* to extract the addresses from the backtrace */
- char **addrs=xbt_new(char*,e->used);
- char buff[256],*p;
-
- /* To read the output of addr2line */
- FILE *pipe;
- char line_func[1024],line_pos[1024];
-
- /* size (in char) of pointers on this arch */
- int addr_len=0;
-
- /* build the commandline */
- curr += sprintf(curr,"%s -f -e %s ",ADDR2LINE,xbt_binary_name);
- for (i=0; i<e->used;i++) {
- /* retrieve this address */
- snprintf(buff,256,"%s",strchr(backtrace[i],'[')+1);
- p=strchr(buff,']');
- *p='\0';
- addrs[i]=bprintf("%s",buff);
-
- /* Add it to the command line args */
- 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);
-
- pipe = popen(cmd, "r");
- if (!pipe) {
- CRITICAL0("Cannot fork addr2line to display the backtrace");
- abort();
- }
- for (i=0; i<e->used; 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';
-
- if (strcmp("??",line_func)) {
- e->bt_strings[i] = bprintf("** In %s() at %s (static symbol)", 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;
-
- char *subcmd;
- FILE *subpipe;
- 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);
- }
- DEBUG2("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;
- }
- DEBUG4("%#lx %s [%#lx-%#lx]",
- addr, found? "in":"out of",first,last);
- }
- fclose(maps);
- free(maps_name);