C snippets:base 64符号化バイナリファイル(jpgピクチャのテスト)
エンコードインタフェースは次のとおりです.
テストプログラム:jpgファイルをbase 64符号化する
const char * base64char = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
char *base64_encode_file(const unsigned char * bindata, char * base64, int binlength)
{
int i, j;
unsigned char current;
for ( i = 0, j = 0 ; i < binlength ; i += 3 )
{
current = (bindata[i] >> 2) ;
current &= (unsigned char)0x3F;
base64[j++] = base64char[(int)current];
current = ( (unsigned char)(bindata[i] << 4 ) ) & ( (unsigned char)0x30 ) ;
if ( i + 1 >= binlength )
{
base64[j++] = base64char[(int)current];
base64[j++] = '=';
base64[j++] = '=';
break;
}
current |= ( (unsigned char)(bindata[i+1] >> 4) ) & ( (unsigned char) 0x0F );
base64[j++] = base64char[(int)current];
current = ( (unsigned char)(bindata[i+1] << 2) ) & ( (unsigned char)0x3C ) ;
if ( i + 2 >= binlength )
{
base64[j++] = base64char[(int)current];
base64[j++] = '=';
break;
}
current |= ( (unsigned char)(bindata[i+2] >> 6) ) & ( (unsigned char) 0x03 );
base64[j++] = base64char[(int)current];
current = ( (unsigned char)bindata[i+2] ) & ( (unsigned char)0x3F ) ;
base64[j++] = base64char[(int)current];
}
base64[j] = '\0';
return 0;
}
テストプログラム:jpgファイルをbase 64符号化する
unsigned int imageSize;
unsigned char *imageBin;
char *imageBase64;
size_t result;
unsigned int base64StrLength;
FILE *fp = NULL;
fp = fopen("test.jpg", "rb"); //
if (NULL == fp)
{
printf("file open failed
");
return -1;
}
//
fseek(fp, 0L, SEEK_END);
imageSize = ftell(fp);
fseek(fp, 0L, SEEK_SET);
//
imageBin = (unsigned char *)malloc(sizeof(unsigned char)*imageSize);
if (NULL == imageBin)
{
printf("malloc failed
");
return -1;
}
//
result = fread(imageBin, 1, imageSize, fp);
if (result != imageSize)
{
printf("file read failed
");
return -1;
}
fclose(fp);
// buffer
imageBase64 = (char *)malloc(sizeof(char)*imageSize*2);// 1/3 ,
if (NULL == imageBase64)
{
printf("malloc failed
");
return -1;
}
//base64
base64_encode_file(imageBin, imageBase64, imageSize);
// imageBase64 base64
free(imageBin);
free(imageBase64);