/*
**  OSSP cfg - Configuration Parsing
**  Copyright (c) 2002-2006 Ralf S. Engelschall <rse@engelschall.com>
**  Copyright (c) 2002-2006 The OSSP Project (http://www.ossp.org/)
**
**  This file is part of OSSP cfg, a configuration parsing
**  library which can be found at http://www.ossp.org/pkg/lib/cfg/.
**
**  Permission to use, copy, modify, and distribute this software for
**  any purpose with or without fee is hereby granted, provided that
**  the above copyright notice and this permission notice appear in all
**  copies.
**
**  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
**  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
**  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
**  IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
**  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
**  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
**  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
**  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
**  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
**  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
**  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
**  SUCH DAMAGE.
**
**  cfg_util.c: utility functions
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "cfg.h"
#include "cfg_util.h"
#include "cfg_global.h"

cfg_rc_t cfg_util_readfile(const char *filename, char **buf_ptr, size_t *buf_size, size_t *buf_used)
{
    FILE *fp = NULL;
    size_t n;
    char *cp;

    if (strcmp(filename, "-") == 0) {
        /* file is given on stdin */
        (*buf_size) = 32;
        if ((*buf_ptr = (char *)malloc(*buf_size)) == NULL)
            return CFG_ERR_SYS;
        cp = *buf_ptr;
        while ((n = fread(cp, 1, (*buf_size)-(cp-(*buf_ptr)), stdin)) > 0) {
            cp += n;
            if (((*buf_ptr)+(*buf_size))-cp < (*buf_size)/8) {
                (*buf_size) *= 2;
                n = cp-(*buf_ptr);
                if ((cp = (char *)realloc(*buf_ptr, *buf_size)) == NULL) {
                    free(*buf_ptr);
                    return CFG_ERR_SYS;
                }
                *buf_ptr = cp;
                cp += n;
            }
        }
        *cp = '\0';
        *buf_used = (cp - *buf_ptr);
    }
    else {
        /* file is given on filesystem */
        if ((fp = fopen(filename, "r")) == NULL)
            return CFG_ERR_SYS;
        fseek(fp, 0, SEEK_END);
        if ((n = ftell(fp)) > 0) {
            if ((*buf_ptr = (char *)malloc(n+1)) == NULL) {
                fclose(fp);
                return CFG_ERR_SYS;
            }
            fseek(fp, 0, SEEK_SET);
            if ((n = fread(*buf_ptr, 1, n, fp)) == 0) {
                free(*buf_ptr);
                fclose(fp);
                return CFG_ERR_SYS;
            }
            (*buf_ptr)[n] = '\0';
            (*buf_size)   = n+1;
            (*buf_used)   = n;
        }
        else {
            (*buf_ptr)  = strdup("");
            (*buf_size) = 1;
            (*buf_used) = 0;
        }
        fclose(fp);
    }
    return CFG_OK;
}