linux_unwind.c

#include <elfutils/libdwfl.h>
#define UNW_LOCAL_ONLY
#include <libunwind.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>

int
main(int argc, const char **argv) {
    hoke_main();
}

bool
hoke_term_colour_enabled(int fd) {
    return isatty(fd) == 0;
}

void
hoke_report_stacktrace(int skip) {
    char *debuginfo_path = NULL;
    const Dwfl_Callbacks callbacks = {
        .find_debuginfo = dwfl_standard_find_debuginfo,
        .find_elf = dwfl_linux_proc_find_elf,
        .debuginfo_path = &debuginfo_path,
    };
    Dwfl *dwfl;
    void *frames[48];
    int n, n_ptrs;

    dwfl = dwfl_begin(&callbacks);

    if (dwfl_linux_proc_report(dwfl, getpid()))
        goto done;

    dwfl_report_end(dwfl, NULL, NULL);

    n_ptrs = backtrace(frames, 48);
    if (n_ptrs < 1)
        goto done;

    fprintf(stderr, "\n");
    for (n = skip + 1; n < n_ptrs; n++) {
        GElf_Addr addr = (uintptr_t) frames[n];
        GElf_Sym sym;
        GElf_Word shndx;
        Dwfl_Module *module = dwfl_addrmodule(dwfl, addr);
        Dwfl_Line *line;
        const char *name, *modname;

        if (!module) {
            fprintf(stderr, "#%-2u ?? [%#" PRIx64 "]\n", n, addr);
            continue;
        }

        name = dwfl_module_addrsym(module, addr, &sym, &shndx);
        if (!name) {
            modname = dwfl_module_info(module, NULL, NULL, NULL,
                    NULL, NULL, NULL, NULL);
            fprintf(stderr, "#%-2u ?? (%s) [%p]\n",
                    n, modname, addr);
            continue;
        }

        line = dwfl_getsrc(dwfl, addr - sym.st_value);
        if (line) {
            int lineno;
            const char *src = dwfl_lineinfo(line, &addr, &lineno,
                    NULL, NULL, NULL);

            if (src) {
                fprintf(stderr, "#%-2u %s+%p (%s:%d) [%p]\n",
                        n, name, addr - sym.st_value,
                        src, lineno, addr);
                continue;
            }
        }

        modname = dwfl_module_info(module, NULL, NULL, NULL,
                NULL, NULL, NULL, NULL);

        fprintf(stderr, "#%-2u %s+%p (%s) [%p]\n",
                n, name, addr - sym.st_value,
                modname, addr);

        if(strcmp(name, "main") == 0) {
            break;
        }
    }
    fprintf(stderr, "\n");

done:
    dwfl_end(dwfl);

}