从base64 C++解码并保存图像文件

#include <openssl/bio.h>
#include <openssl/evp.h>
#include <openssl/buffer.h>
#include <fstream>

void base64DecodeAndSaveImage(const std::string& base64Data, const std::string& filename) {
    // 创建BIO对象
    BIO* bio = BIO_new(BIO_f_base64());
    BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);

    // 创建内存BIO对象
    BIO* memBio = BIO_new_mem_buf(base64Data.c_str(), base64Data.length());

    // 将内存BIO连接到base64解码BIO
    BIO_push(bio, memBio);

    // 创建输出文件流
    std::ofstream outputFile(filename, std::ios::binary);

    // 缓冲区大小
    const int bufferSize = 4096;
    char buffer[bufferSize];

    // 从base64解码BIO中读取数据并写入文件
    int bytesRead;
    while ((bytesRead = BIO_read(bio, buffer, bufferSize)) > 0) {
        outputFile.write(buffer, bytesRead);
    }

    // 释放资源
    BIO_free_all(bio);
    outputFile.close();
}

std::string base64Data = "Base64编码的图像数据";
std::string filename = "image.jpg";
base64DecodeAndSaveImage(base64Data, filename);