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Replaced Exiv2::base64encode() because last effort failed unit test on msvc.

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clanmills
2021-03-06 20:23:19 +00:00
parent 80e20304cb
commit 1eeeecea50
1 changed files with 36 additions and 47 deletions
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src/futils.cpp
+36 -47
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@@ -140,53 +140,42 @@ namespace Exiv2 {
}
int base64encode(const void* data_buf, size_t dataLength, char* result, size_t resultSize) {
// https://vorbrodt.blog/2019/03/23/base64-encoding/
const char kEncodeLookup[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
const char kPadCharacter = '=';
std::string encoded;
encoded.reserve(((dataLength / 3) + (dataLength % 3 > 0)) * 4);
uint32_t temp ;
unsigned char* b = (unsigned char*) data_buf;
size_t i = 0 ;
while ( i < dataLength / 3 )
{
temp = b[i+0] << 16;
temp += b[i+1] << 8;
temp += b[i+2];
encoded.append(1, kEncodeLookup[(temp & 0x00FC0000) >> 18]);
encoded.append(1, kEncodeLookup[(temp & 0x0003F000) >> 12]);
encoded.append(1, kEncodeLookup[(temp & 0x00000FC0) >> 6 ]);
encoded.append(1, kEncodeLookup[(temp & 0x0000003F) ]);
i++ ;
}
switch(dataLength % 3)
{
case 1:
temp = b[i+0] << 16;
encoded.append(1, kEncodeLookup[(temp & 0x00FC0000) >> 18]);
encoded.append(1, kEncodeLookup[(temp & 0x0003F000) >> 12]);
encoded.append(2, kPadCharacter);
break;
case 2:
temp = b[i+0] << 16;
temp += b[i+1] << 8;
encoded.append(1, kEncodeLookup[(temp & 0x00FC0000) >> 18]);
encoded.append(1, kEncodeLookup[(temp & 0x0003F000) >> 12]);
encoded.append(1, kEncodeLookup[(temp & 0x00000FC0) >> 6 ]);
encoded.append(1, kPadCharacter);
break;
}
size_t length = encoded.size();
int rc = length < resultSize ? 1 : 0;
if (rc) {
::memcpy(result,encoded.c_str(),length);
result[length]=0;
}
return rc;
char encoding_table[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '+', '/'};
size_t mod_table[] = {0, 2, 1};
// https://stackoverflow.com/questions/342409/how-do-i-base64-encode-decode-in-c
size_t output_length = 4 * ((dataLength + 2) / 3);
int rc = result && data_buf && output_length < resultSize ? 1 : 0;
if ( rc ) {
const unsigned char* data = (const unsigned char*) data_buf ;
::memset(result,0,resultSize);
for (size_t i = 0, j = 0 ; i < dataLength;) {
uint32_t octet_a = i < dataLength ? data[i++] : 0;
uint32_t octet_b = i < dataLength ? data[i++] : 0;
uint32_t octet_c = i < dataLength ? data[i++] : 0;
uint32_t triple = (octet_a << 0x10) + (octet_b << 0x08) + octet_c;
result[j++] = encoding_table[(triple >> 3 * 6) & 0x3F];
result[j++] = encoding_table[(triple >> 2 * 6) & 0x3F];
result[j++] = encoding_table[(triple >> 1 * 6) & 0x3F];
result[j++] = encoding_table[(triple >> 0 * 6) & 0x3F];
}
for (size_t i = 0; i < mod_table[dataLength % 3]; i++)
result[output_length - 1 - i] = '=';
result[output_length]=0;
}
return rc;
} // base64encode
long base64decode(const char *in, char *out, size_t out_size) {