tinyproxy/src/heap.c

/* tinyproxy - A fast light-weight HTTP proxy
 * Copyright (C) 2002 Robert James Kaes <rjkaes@users.sourceforge.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* Debugging versions of various heap related functions are combined
 * here.  The debugging versions include assertions and also print
 * (to standard error) the function called along with the amount
 * of memory allocated, and where the memory is pointing.  The
 * format of the log message is standardized.
 */

#include "tinyproxy.h"
#include "heap.h"
#include "text.h"

void *
debugging_calloc(size_t nmemb, size_t size, const char *file,
                 unsigned long line)
{
        void *ptr;

        assert(nmemb > 0);
        assert(size > 0);

        ptr = calloc(nmemb, size);
        fprintf(stderr, "{calloc: %p:%zu x %zu} %s:%lu\n", ptr, nmemb, size, file,
                line);
        return ptr;
}

void *
debugging_malloc(size_t size, const char *file, unsigned long line)
{
        void *ptr;

        assert(size > 0);

        ptr = malloc(size);
        fprintf(stderr, "{malloc: %p:%zu} %s:%lu\n", ptr, size, file, line);
        return ptr;
}

void *
debugging_realloc(void *ptr, size_t size, const char *file, unsigned long line)
{
        void *newptr;

        assert(size > 0);

        newptr = realloc(ptr, size);
        fprintf(stderr, "{realloc: %p -> %p:%zu} %s:%lu\n", ptr, newptr, size,
                file, line);
        return newptr;
}

void
debugging_free(void *ptr, const char *file, unsigned long line)
{
        fprintf(stderr, "{free: %p} %s:%lu\n", ptr, file, line);

        if (ptr != NULL)
                free(ptr);
        return;
}

char *
debugging_strdup(const char *s, const char *file, unsigned long line)
{
        char *ptr;
        size_t len;

        assert(s != NULL);

        len = strlen(s) + 1;
        ptr = malloc(len);
        if (!ptr)
                return NULL;
        memcpy(ptr, s, len);

        fprintf(stderr, "{strdup: %p:%zu} %s:%lu\n", ptr, len, file, line);
        return ptr;
}

/*
 * Allocate a block of memory in the "shared" memory region.
 *
 * FIXME: This uses the most basic (and slowest) means of creating a
 * shared memory location.  It requires the use of a temporary file.  We might
 * want to look into something like MM (Shared Memory Library) for a better
 * solution.
 */
void *
malloc_shared_memory(size_t size)
{
        int fd;
        void *ptr;
        char buffer[32];

        static char *shared_file = "/tmp/tinyproxy.shared.XXXXXX";

        assert(size > 0);

        strlcpy(buffer, shared_file, sizeof(buffer));

        /* Only allow u+rw bits. This may be required for some versions
         * of glibc so that mkstemp() doesn't make us vulnerable.
         */
        umask(0177);

        if ((fd = mkstemp(buffer)) == -1)
                return MAP_FAILED;
        unlink(buffer);

        if (ftruncate(fd, size) == -1)
                return MAP_FAILED;
        ptr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);

        return ptr;
}

/*
 * Allocate a block of memory from the "shared" region an initialize it to
 * zero.
 */
void *
calloc_shared_memory(size_t nmemb, size_t size)
{
        void *ptr;
        long length;

        assert(nmemb > 0);
        assert(size > 0);

        length = nmemb * size;

        ptr = malloc_shared_memory(length);
        if (ptr == MAP_FAILED)
                return ptr;

        memset(ptr, 0, length);

        return ptr;
}