gistfile1.txt

#include <execinfo.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>

static volatile int party = 1;

static void full_write(int fd, const char *buf, size_t len)
{
        while (len > 0) {
                ssize_t ret = write(fd, buf, len);

                if ((ret == -1) && (errno != EINTR))
                        break;

                buf += (size_t) ret;
                len -= (size_t) ret;
        }
}

void print_backtrace(void* p2)
{
        party = 0;
        static const char start[] = "BACKTRACE ------------\n";
        static const char end[] = "----------------------\n";

        void *bt[1024];
        int bt_size;
        char **bt_syms;
        int i;

        bt_size = backtrace(bt, 1024);
        bt_syms = backtrace_symbols(bt, bt_size);
        full_write(STDERR_FILENO, start, strlen(start));
        for (i = 1; i < bt_size; i++) {
                size_t len = strlen(bt_syms[i]);
                full_write(STDERR_FILENO, bt_syms[i], len);
                full_write(STDERR_FILENO, "\n", 1);
        }
        full_write(STDERR_FILENO, end, strlen(end));
    free(bt_syms);
    party = 1;
}

static void mtrace_init(void)
{
    real_malloc = dlsym(RTLD_NEXT, "malloc");
    if (NULL == real_malloc) {
        fprintf(stderr, "Error in `dlsym`: %s\n", dlerror());
    }
}

void *malloc(size_t size)
{
    if(real_malloc==NULL) {
        mtrace_init();
    }

    void *p = NULL;
    fprintf(stderr, "malloc(%d) = ", size);
    if(party){
        print_backtrace(real_malloc);
    }
    p = real_malloc(size);
    fprintf(stderr, "%p\n", p);
    return p;
}