/***
  This file is part of libsydney.

  Copyright 2008 Lennart Poettering

  libsydney 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.

  libsydney 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 libsydney. If not, see
  <http://www.gnu.org/licenses/>.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <errno.h>

#include "macro.h"
#include "malloc.h"

static sa_allocator allocator = {
    .malloc = NULL,
    .calloc = NULL,
    .free = NULL,
    .realloc = NULL
};

void* sa_malloc(size_t size) {
    void *ptr;

    if (size <= 0)
        return NULL;

    if (allocator.malloc)
        ptr = allocator.malloc(size);
    else
        ptr = malloc(size);

    if (!ptr)
        errno = ENOMEM;

    return ptr;
}

void sa_free(void *ptr) {
    int saved_errno;

    if (!ptr)
        return;

    saved_errno = errno;

    if (allocator.free)
        allocator.free(ptr);
    else
        free(ptr);

    errno = saved_errno;
}

void* sa_malloc0(size_t size) {
    void *ptr;

    if (size <= 0)
        return NULL;

    if (allocator.calloc)
        ptr = allocator.calloc(1, size);
    else if (allocator.malloc) {
        if ((ptr = allocator.malloc(size)))
            memset(ptr, 0, size);
    } else
        ptr = calloc(1, size);

    if (!ptr)
        errno = ENOMEM;

    return ptr;
}

char *sa_strdup(const char *s) {
    char *p;
    size_t n_avail;

    if (!s)
        return NULL;

    n_avail = strlen(s);

    if (!(p = sa_new(char, n_avail + 1)))
        return NULL;

    memcpy(p, s, n_avail);
    p[n_avail] = 0;

    return p;
}

char *sa_strndup(const char *s, size_t n) {
    size_t n_avail;
    char *p;

    if (!s)
        return NULL;

    if (memchr(s, '\0', n)) {
        n_avail = strlen(s);
        if (n_avail > n)
            n_avail = n;
    } else
        n_avail = n;

    if (!(p = sa_new(char, n_avail + 1)))
        return NULL;

    memcpy(p, s, n_avail);
    p[n_avail] = 0;

    return p;
}

void* sa_memdup(const void* p, size_t size) {
    void *r;

    sa_assert(p);

    if (!(r = sa_malloc(size)))
        return NULL;

    memcpy(r, p, size);
    return r;
}

char *sa_sprintf_malloc(const char *format, ...) {
    size_t  size = 100;
    char *c = NULL;

    sa_assert(format);

    for(;;) {
        int r;
        va_list ap;

        sa_free(c);

        if (!(c = sa_new(char, size)))
            return NULL;

        va_start(ap, format);
        r = vsnprintf(c, size, format, ap);
        va_end(ap);

        c[size-1] = 0;

        if (r > -1 && (size_t) r < size)
            return c;

        if (r > -1)    /* glibc 2.1 */
            size = (size_t) r+1;
        else           /* glibc 2.0 */
            size *= 2;
    }
}

void sa_set_allocator(const sa_allocator *a) {
    memcpy(&allocator, a, sizeof(allocator));
}