source: MondoRescue/branches/stable/mindi-busybox/libbb/read_package_field.c@ 821

/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) many different people.
 * If you wrote this, please acknowledge your work.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#include <stdlib.h>
#include <string.h>
#include "libbb.h"

/*
 * Gets the next package field from package_buffer, seperated into the field name
 * and field value, it returns the int offset to the first character of the next field
 */
int read_package_field(const char *package_buffer, char **field_name, char **field_value)
{
    int offset_name_start = 0;
    int offset_name_end = 0;
    int offset_value_start = 0;
    int offset_value_end = 0;
    int offset = 0;
    int next_offset;
    int name_length;
    int value_length;
    int exit_flag = FALSE;

    if (package_buffer == NULL) {
        *field_name = NULL;
        *field_value = NULL;
        return(-1);
    }
    while (1) {
        next_offset = offset + 1;
        switch (package_buffer[offset]) {
            case('\0'):
                exit_flag = TRUE;
                break;
            case(':'):
                if (offset_name_end == 0) {
                    offset_name_end = offset;
                    offset_value_start = next_offset;
                }
                /* TODO: Name might still have trailing spaces if ':' isnt
                 * immediately after name */
                break;
            case('\n'):
                /* TODO: The char next_offset may be out of bounds */
                if (package_buffer[next_offset] != ' ') {
                    exit_flag = TRUE;
                    break;
                }
            case('\t'):
            case(' '):
                /* increment the value start point if its a just filler */
                if (offset_name_start == offset) {
                    offset_name_start++;
                }
                if (offset_value_start == offset) {
                    offset_value_start++;
                }
                break;
        }
        if (exit_flag) {
            /* Check that the names are valid */
            offset_value_end = offset;
            name_length = offset_name_end - offset_name_start;
            value_length = offset_value_end - offset_value_start;
            if (name_length == 0) {
                break;
            }
            if ((name_length > 0) && (value_length > 0)) {
                break;
            }

            /* If not valid, start fresh with next field */
            exit_flag = FALSE;
            offset_name_start = offset + 1;
            offset_name_end = 0;
            offset_value_start = offset + 1;
            offset_value_end = offset + 1;
            offset++;
        }
        offset++;
    }
    if (name_length == 0) {
        *field_name = NULL;
    } else {
        *field_name = bb_xstrndup(&package_buffer[offset_name_start], name_length);
    }
    if (value_length > 0) {
        *field_value = bb_xstrndup(&package_buffer[offset_value_start], value_length);
    } else {
        *field_value = NULL;
    }
    return(next_offset);
}