代碼不穩订,大俠幫看看

代碼不穩定,大俠幫看看

C/C++ code

/*
参数：
    szSrc       源字符串
    szPattern   要查找的字符串
    szDelimiter 分隔符表
    ppFound     存放查找到的位置
    nMaxFound   ppFound的大小
返回值：
    找到的符合条件的位置数
用法：
    char *ppFound[100];
    char *szDelimiter = " \t\r\n,.;+-'\"[]{}()*&^%$#@!";  // 自定义分隔符表
    int nFound = ExactlyMatch(szSrc, szPattern, szDelimiter, ppFound, 100);
*/
int ExactlyMatch(const char *szSrc, const char *szPattern, const char *szDelimiter,const char *ppFound[], int nMaxFound) {
    const char *pchStart = NULL;
    const char *pch = szSrc;
    int nFound = 0;

    while ( true ) {
        bool bIsDelimiter = strchr(szDelimiter, *pch) || (*pch == '\0');
        if (  bIsDelimiter ) {
            if ( pchStart != NULL ) {
                int len = pch - pchStart;
                if ( strncmp(pchStart, szPattern, len) == 0 ) {
                    ppFound[nFound++] = pchStart;
                    if ( nFound == nMaxFound )
                        return -1;
                }
            }
            pchStart = NULL;
        } else {
            if ( pchStart == NULL )
                pchStart = pch;
        }
        if ( *pch++ == '\0' )
            break;
    }
    return nFound;
}

用这个代码查询字符串,偶尔会出现查漏的情况,查*.frm的时候,有时还会出错,错误代码:
Project Project1.exe raised exception class EAccessViolation with message

'Access violation at address 00403B01 in module 'Project1.exe'. Read of

address 00A10008'. Process stopped. Use Step or Run to continue.

Access violation at address 00403 B01 in module 'Project1. Exe'. Read of

address 00 A10008.

大侠帮看看代码要如何改进,功能是精确查找.

------解决方案--------------------
查了一下，这个函数有多查的问题，但没测出漏查，新改进的函数如下：

C/C++ code


//---------------------------------------
/* 参数：
    szSrc 源字符串
    szPattern 要查找的字符串
    szDelimiter 分隔符表
    ppFound 存放查找到的位置
    nMaxFound ppFound的大小
返回值： 找到的符合条件的位置数
         -1表示数量超出ppFound的大小
用法：
    char *ppFound[100];
    char *szDelimiter = " \t\r\n,.;+-'\"[]{}()*&^%$#@!"; // 自定义分隔符表
    int nFound = ExactlyMatch(szSrc, szPattern, szDelimiter, ppFound, 100);
*/
int ExactlyMatch(const char *szSrc, const char *szPattern, const char *szDelimiter, const char *ppFound[], int nMaxFound) {
    const char *pchStart = NULL;
    const char *pch = szSrc;
    int nFound = 0;
    int nPatternLen = strlen(szPattern);

    while ( true ) {
        bool bIsDelimiter = strchr(szDelimiter, *pch) || (*pch == '\0');
        if ( bIsDelimiter ) {
            if ( pchStart != NULL ) {
                int len = pch - pchStart;
                if ( len == nPatternLen && strncmp(pchStart, szPattern, len) == 0 ) {
                    ppFound[nFound++] = pchStart;
                    if ( nFound == nMaxFound )
                        return -1;
                }
            }
            pchStart = NULL;
        } else {
            if ( pchStart == NULL )
                pchStart = pch;
        }

        if ( *pch++ == '\0' )
            break;
    }

    return nFound;
}

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