cryptopp的filesh修改版C语言函数代码

以下是Cryptopp的files.h修改版的C语言函数代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "cryptopp/cryptlib.h"
#include "cryptopp/files.h"

int WriteFile(const char* filename, const byte* data, size_t length) {
    FILE* file = fopen(filename, "wb");
    if (file == NULL) {
        return -1;  // failed to open file
    }

    size_t written = fwrite(data, 1, length, file);
    fclose(file);

    if (written != length) {
        return -2;  // failed to write data
    }

    return 0;  // success
}

int ReadFile(const char* filename, byte** data, size_t* length) {
    FILE* file = fopen(filename, "rb");
    if (file == NULL) {
        return -1;  // failed to open file
    }

    fseek(file, 0, SEEK_END);
    long fileLength = ftell(file);
    fseek(file, 0, SEEK_SET);

    *data = (byte*)malloc(fileLength);
    if (*data == NULL) {
        fclose(file);
        return -2;  // failed to allocate memory
    }

    size_t bytesRead = fread(*data, 1, fileLength, file);
    fclose(file);

    if (bytesRead != fileLength) {
        free(*data);
        return -3;  // failed to read data
    }

    *length = fileLength;
    return 0;  // success
}

以上代码包含了两个函数：WriteFile用于将数据写入文件，ReadFile用于从文件中读取数据。这些函数使用C标准库中的文件操作函数实现了Cryptopp的files.h中的相应功能