src/core/utils/parse_cmdline.cpp

/*
 *  Copyright (c) 2018, The OpenThread Authors.
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. Neither the name of the copyright holder nor the
 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *  AND ANY EXPRESS 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 COPYRIGHT HOLDER OR 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
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 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @file
 *   This file implements the command line parser.
 */

#include <string.h>

#include "parse_cmdline.hpp"

#include "common/code_utils.hpp"

namespace ot {
namespace Utils {

static bool IsSeparator(char aChar)
{
    return (aChar == ' ') || (aChar == '\t') || (aChar == '\r') || (aChar == '\n');
}

static bool IsEscapable(char aChar)
{
    return IsSeparator(aChar) || (aChar == '\\');
}

otError CmdLineParser::ParseCmd(char *aString, uint8_t &aArgsLength, char *aArgs[], uint8_t aArgsLengthMax)
{
    otError error = OT_ERROR_NONE;
    char *  cmd;

    aArgsLength = 0;

    for (cmd = aString; *cmd; cmd++)
    {
        if ((*cmd == '\\') && IsEscapable(*(cmd + 1)))
        {
            // include the null terminator: strlen(cmd) = strlen(cmd + 1) + 1
            memmove(cmd, cmd + 1, strlen(cmd));
        }
        else if (IsSeparator(*cmd))
        {
            *cmd = '\0';
        }

        if ((*cmd != '\0') && ((aArgsLength == 0) || (*(cmd - 1) == '\0')))
        {
            VerifyOrExit(aArgsLength < aArgsLengthMax, error = OT_ERROR_INVALID_ARGS);
            aArgs[aArgsLength++] = cmd;
        }
    }

exit:
    return error;
}

} // namespace Utils
} // namespace ot