#include <execinfo.h>
#include <stdio.h>
#include <stdlib.h>
#include "ucore/backtrace.h"

#define MAX_BACKTRACE_SYMBOLS 96

void uc_backtrace_fd(int fd)
{
    void *buffer[MAX_BACKTRACE_SYMBOLS];
    void **syms;
    int ptrs;

    ptrs = backtrace(buffer, MAX_BACKTRACE_SYMBOLS);
    if (ptrs > 0) { //dont print out this function
        ptrs--;
        syms = &buffer[1];
    } else {
        syms = &buffer[0];
    }

    backtrace_symbols_fd(syms, ptrs, fd);
}

void uc_backtrace_buf(char *buf, size_t len)
{
    void *buffer[MAX_BACKTRACE_SYMBOLS];
    int ptrs;
    char **lines;
    size_t remaining = len;
    int i;
    
    ptrs = backtrace(buffer, MAX_BACKTRACE_SYMBOLS);

    buf[0] = 0;

    lines = backtrace_symbols(buffer, ptrs);
    for (i = 1; i < ptrs; i++) {

        int rc = snprintf(buf, remaining, "%s\n", lines[i]);
        
        if (rc <= 0 || (size_t)rc >= remaining) {
            break;
        }

        remaining -= rc;
        buf += rc;
    }

    free(lines);
}