1#include <corkscrew/backtrace.h> 2#include <corkscrew/symbol_table.h> 3#include <stdio.h> 4#include <stdlib.h> 5 6int do_backtrace(float /* just to test demangling */) { 7 const size_t MAX_DEPTH = 32; 8 backtrace_frame_t* frames = (backtrace_frame_t*) malloc(sizeof(backtrace_frame_t) * MAX_DEPTH); 9 ssize_t frame_count = unwind_backtrace(frames, 0, MAX_DEPTH); 10 fprintf(stderr, "frame_count=%d\n", (int) frame_count); 11 if (frame_count <= 0) { 12 return frame_count; 13 } 14 15 backtrace_symbol_t* backtrace_symbols = (backtrace_symbol_t*) malloc(sizeof(backtrace_symbol_t) * frame_count); 16 get_backtrace_symbols(frames, frame_count, backtrace_symbols); 17 18 for (size_t i = 0; i < (size_t) frame_count; ++i) { 19 char line[MAX_BACKTRACE_LINE_LENGTH]; 20 format_backtrace_line(i, &frames[i], &backtrace_symbols[i], 21 line, MAX_BACKTRACE_LINE_LENGTH); 22 if (backtrace_symbols[i].symbol_name != NULL) { 23 // get_backtrace_symbols found the symbol's name with dladdr(3). 24 fprintf(stderr, " %s\n", line); 25 } else { 26 // We don't have a symbol. Maybe this is a static symbol, and 27 // we can look it up? 28 symbol_table_t* symbols = NULL; 29 if (backtrace_symbols[i].map_name != NULL) { 30 symbols = load_symbol_table(backtrace_symbols[i].map_name); 31 } 32 const symbol_t* symbol = NULL; 33 if (symbols != NULL) { 34 symbol = find_symbol(symbols, frames[i].absolute_pc); 35 } 36 if (symbol != NULL) { 37 int offset = frames[i].absolute_pc - symbol->start; 38 fprintf(stderr, " %s (%s%+d)\n", line, symbol->name, offset); 39 } else { 40 fprintf(stderr, " %s (\?\?\?)\n", line); 41 } 42 free_symbol_table(symbols); 43 } 44 } 45 46 free_backtrace_symbols(backtrace_symbols, frame_count); 47 free(backtrace_symbols); 48 free(frames); 49 return frame_count; 50} 51 52struct C { 53 int g(int i); 54}; 55 56__attribute__ ((noinline)) int C::g(int i) { 57 if (i == 0) { 58 return do_backtrace(0.1); 59 } 60 return g(i - 1); 61} 62 63extern "C" __attribute__ ((noinline)) int f() { 64 C c; 65 return c.g(5); 66} 67 68int main() { 69 flush_my_map_info_list(); 70 f(); 71 72 flush_my_map_info_list(); 73 f(); 74 75 return 0; 76} 77