conversions.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2017, Digium, Inc.
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
/*! \file
 *
 * \brief Conversion utility functions
 */
 
/*** MODULEINFO
    <support_level>core</support_level>
 ***/
 
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <inttypes.h>
#include <stdio.h>
 
#include "asterisk/conversions.h"
 
static int str_is_negative(const char **str)
{
    /*
     * Ignore any preceding white space. It's okay to move the pointer here
     * since the converting function would do the same, i.e. skip white space.
     */
    while (isspace(**str)) ++*str;
    return **str == '-';
}
 
int ast_str_to_int(const char *str, int *res)
{
    intmax_t val;
 
    if (ast_str_to_imax(str, &val) || val < INT_MIN || val > INT_MAX) {
        return -1;
    }
 
    *res = val;
    return 0;
}
 
int ast_str_to_uint(const char *str, unsigned int *res)
{
    uintmax_t val;
 
    if (ast_str_to_umax(str, &val) || val > UINT_MAX) {
        return -1;
    }
 
    *res = val;
    return 0;
}
 
int ast_str_to_long(const char *str, long *res)
{
    intmax_t val;
 
    if (ast_str_to_imax(str, &val) || val < LONG_MIN || val > LONG_MAX) {
        return -1;
    }
 
    *res = val;
    return 0;
}
 
int ast_str_to_ulong(const char *str, unsigned long *res)
{
    uintmax_t val;
 
    if (ast_str_to_umax(str, &val) || val > ULONG_MAX) {
        return -1;
    }
 
    *res = val;
    return 0;
}
 
int ast_str_to_imax(const char *str, intmax_t *res)
{
    char *end;
    intmax_t val;
 
    if (!str) {
        return -1;
    }
 
    errno = 0;
    val = strtoimax(str, &end, 10);
 
    /*
     * If str equals end then no digits were found. If end is not pointing to
     * a null character then the string contained some numbers that could be
     * converted, but some characters that could not, which we'll consider
     * invalid.
     */
    if (str == end || *end != '\0' || (errno == ERANGE &&
            (val == INTMAX_MIN || val == INTMAX_MAX))) {
        return -1;
    }
 
    *res = val;
    return 0;
}
 
int ast_str_to_umax(const char *str, uintmax_t *res)
{
    char *end;
    uintmax_t val;
 
    if (!str || str_is_negative(&str)) {
        return -1;
    }
 
    errno = 0;
    val = strtoumax(str, &end, 10);
 
    /*
     * If str equals end then no digits were found. If end is not pointing to
     * a null character then the string contained some numbers that could be
     * converted, but some characters that could not, which we'll consider
     * invalid.
     */
    if ((str == end || *end != '\0' || (errno == ERANGE && val == UINTMAX_MAX))) {
        return -1;
    }
 
    *res = val;
    return 0;
}