capsule-shim.h

// Copyright © 2017 Collabora Ltd

// This file is part of libcapsule.

// libcapsule is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 2.1 of the
// License, or (at your option) any later version.

// libcapsule is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.

// You should have received a copy of the GNU Lesser General Public
// License along with libcapsule.  If not, see <http://www.gnu.org/licenses/>.

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <execinfo.h>

#include <capsule/capsule.h>

#define UNVERSIONED_STUB(name) \
    void name (void) __attribute__((noreturn,visibility("default"))); \
    void name (void)                                   \
    {                                                  \
        fprintf(stderr, "! SHIM " #name " called\n" ); \
        backtrace_shim_call();                         \
        abort();                                       \
    }

#define VERSIONED_STUB(name,version) \
    UNVERSIONED_STUB(name);

static void
backtrace_shim_call (void)
{
    void *trace[16] = { NULL };
    int traced = 0;
    char **symbols = NULL;

    traced  = backtrace( trace, sizeof(trace)/sizeof(void *) );
    symbols = backtrace_symbols( trace, traced );

    for( int x = 1; x < traced; x++ )
        fprintf( stderr, "  -> %s\n", symbols[x] );

    free( symbols );
}

// We don't support versioned symbols properly yet, they need som
// asm magic that looks like this and I'm not clear on the details:
// __asm__(".symver _" #name "," #name #version)