在C语言中使用libb64进行Base64编解码

libb64下载地址http://sourceforge.net/projects/libb64

以下为Demo

libb64_demo.c

#include <stdio.h>
#include <string.h>
#include <libb64/cencode.h>
#include <libb64/cdecode.h>
void base64EncodeString(const char *textToEncode, char *buffer);
void base64DecodeString(const char *codeToDecode, char *buffer);
void base64EncodeFile(FILE *fileToEncode, FILE *encodedFile);
void base64DecodeFile(FILE *encodedFile, FILE *decodedFile);
int main()
{
    const char *text = "Matt Damon";
    char buffer[];
    base64EncodeString(text, buffer);
    printf("%s", buffer);
    const char *code = "R29vZCBXaWxsIEh1bnRpbmc=";
    base64DecodeString(code, buffer);
    printf("%s\n", buffer);
    const char *inputFilename = "易语言5.2修正版.rar";
    FILE *inputFile = fopen(inputFilename, "rb");
    if (inputFile)
    {
        const char *encodedFilename = "易语言5.2修正版.rar.txt";
        FILE *encodedFile = fopen(encodedFilename, "wb");
        if (encodedFile)
        {
            base64EncodeFile(inputFile, encodedFile);
            fclose(encodedFile);
        }
        else
            printf("Cannot open file: %s\n", encodedFile);
        fclose(inputFile);
    }
    else
        printf("Cannot open file: %s\n", inputFilename);
    const char *encodedFilename = "360DrvMgrInstaller_net.exe.txt";
    FILE *encodedFile = fopen(encodedFilename, "rb");
    if (encodedFile)
    {
        const char *decodedFilename = "360DrvMgrInstaller_net";
        FILE *decodedFile = fopen(decodedFilename, "wb");
        if (decodedFile)
        {
            base64DecodeFile(encodedFile, decodedFile);
            fclose(decodedFile);
        }
        else
            printf("Cannot open file: %s\n", decodedFile);
        fclose(encodedFile);
    }
    else
        printf("Cannot open file: %s\n", encodedFilename);
    system("pause");
    return ;
}
void base64EncodeString(const char *textToEncode, char *buffer)
{
    base64_encodestate state;
    base64_init_encodestate(&state);
    int numberOfBytesEncoded = base64_encode_block(textToEncode, strlen(textToEncode), buffer, &state);
    numberOfBytesEncoded += base64_encode_blockend(buffer + numberOfBytesEncoded, &state);
    buffer[numberOfBytesEncoded] = '\0';
}
void base64DecodeString(const char *codeToDecode, char *buffer)
{
    base64_decodestate state;
    base64_init_decodestate(&state);
    int numberOfCharactersDecoded = base64_decode_block(codeToDecode, strlen(codeToDecode), buffer, &state);
    buffer[numberOfCharactersDecoded] = '\0';
}
void base64EncodeFile(FILE *fileToEncode, FILE *encodedFile)
{
    char readBuffer[];
    char encodedBuffer[];
    int numberOfBytesEncoded;
    base64_encodestate state;
    base64_init_encodestate(&state);
    while (!feof(fileToEncode))
    {
        size_t numberOfObjects = fread(readBuffer, sizeof(char), , fileToEncode);
        numberOfBytesEncoded = base64_encode_block(readBuffer, numberOfObjects, encodedBuffer, &state);
        fwrite(encodedBuffer, sizeof(char), numberOfBytesEncoded, encodedFile);
    }
    numberOfBytesEncoded = base64_encode_blockend(encodedBuffer, &state);
    fwrite(encodedBuffer, sizeof(char), numberOfBytesEncoded, encodedFile);
}
void base64DecodeFile(FILE *encodedFile, FILE *decodedFile)
{
    char inputBuffer[];
    char decodedBuffer[];
    int numberOfBytesDecoded;
    base64_decodestate state;
    base64_init_decodestate(&state);
    while (!feof(encodedFile))
    {
        size_t numberOfCharacters = fread(inputBuffer, sizeof(char), , encodedFile);
        numberOfBytesDecoded = base64_decode_block(inputBuffer, numberOfCharacters, decodedBuffer, &state);
        fwrite(decodedBuffer, sizeof(char), numberOfBytesDecoded, decodedFile);
    }
}