parselib.c

介绍ROCK OS操作系统.一般用于汽车电子,类似OCVX.里面是个DEMO文档,内附说明.

/******************************************************************************
    Copyright (c) 2006 by RockOS.
    All rights reserved.

    This software is supported by the Rock Software Workroom only.

    Any bugs please contact the author with e-mail or QQ:
     E-mail : [e-mail]
         QQ : 59681888
*******************************************************************************
File name   : parselib.c
Description : parse command line library for RockOS' shell.
            : 
            : 
Auther      : sunxinqiu
History     :
  2006-3-15   first release.
******************************************************************************/

#include "os.h"

/******************************************************************************
Function    : STATUS parseCmdLine()
Params      : cmdLine - command line get from shell prompt.
            : cmdName - the command name parsed from cmdLine.
            : argc    - total argument count for this command.
            : argv    - the arguments list for this command.
            : 
Return      : OS_SUCCESS for parsing successfully, or OS_FAIL.
Description : parse the command line before executing the proper shell command
            : function.
******************************************************************************/
STATUS parseCmdLine (char * cmdLine,
                        char * cmdName,
                        int  * argc,
                        char * argv[])
{
    BOOL parsingKey;
    BOOL parsingString;

    int n;

    char ch;
    int  length;

    * argc = 0;
    cmdName[0] = 0;
    argv[0] = NULL;

    /* skip the leading spaces & TABs. */
    length = 0;
    ch = cmdLine[0];
    if (ch == '\0')
    {
        /* null command line. */
        return OS_SUCCESS;
    }
    else
    {
        while ((ch == ' ')||(ch == '\t'))
        {
            length++;
            ch = cmdLine[length];
            if (ch == '\0')
            {
                return OS_SUCCESS;
            }
        }
    }

    /* start parse command, argv[0] first. */
    n = 0;
    argv[0] = &cmdLine[length];
    parsingKey = OS_TRUE;
    parsingString = OS_FALSE;
    while (ch != '\0')
    {
        switch (ch)
        {
        case ' ':   /* 0x20, space */
        case '\t':  /* 0x09, TAB   */
        case ',':   /* 0x2c, comma (,) */
            if (parsingKey != OS_TRUE)
            {
                /* skip this separator char*/
                ;
            }
            else if (parsingString == OS_TRUE)
            {
                ;
            }
            else
            {
                parsingKey = OS_FALSE;
                cmdLine[length] = '\0';
                n++;
            }
            break;

        case '\"':  /* 0x22, double quotation (") */
            if ((parsingKey == OS_TRUE)&&(parsingString == OS_FALSE))
            {
                /* error: double quotation occurs in a key word or argument. */
                OS_printf("parseCmdLine(): doule quotation can't be used as a seperator!!!\n");
                return OS_FAIL;
            }
            else if ((parsingKey == OS_FALSE)&&(parsingString == OS_FALSE))
            {
                /* a string argument begins here. */
                parsingKey = OS_TRUE;
                parsingString = OS_TRUE;
                argv[n] = &cmdLine[length];
            }
            else if ((parsingKey == OS_TRUE)&&(parsingString == OS_TRUE))
            {
                /* a string argument ends here. */
                parsingKey = OS_FALSE;
                parsingString = OS_FALSE;
                cmdLine[length] = '\0';
            }
            else
            {
                /* error: double quotation occurs leading a command line.*/
                OS_printf("");
                return OS_FAIL;
            }
            break;

        default:
            if (parsingString != OS_TRUE)
            {
                if (parsingKey != OS_TRUE)
                {
                    argv[n] = &cmdLine[length];
                    parsingKey = OS_TRUE;
                }
            }
            break;
        }

        length++;
        ch = cmdLine[length];
    }
    
    * argc = n + 1;
    strcpy (&cmdName[0], argv[0]);
    return OS_SUCCESS;
}