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-rw-r--r--plugins/JSON/Source/JSON_Base64.cpp111
1 files changed, 111 insertions, 0 deletions
diff --git a/plugins/JSON/Source/JSON_Base64.cpp b/plugins/JSON/Source/JSON_Base64.cpp
new file mode 100644
index 0000000000..fcde330b1a
--- /dev/null
+++ b/plugins/JSON/Source/JSON_Base64.cpp
@@ -0,0 +1,111 @@
+#include "JSON_Base64.h"
+#include "JSONDefs.h"
+
+#ifdef JSON_BINARY //if this is not needed, don't waste space compiling it
+
+static const json_char * chars64 = JSON_TEXT("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/");
+#ifdef JSON_UNICODE
+ static std::string BASE64_EMPTY_STRING;
+#else
+ #define BASE64_EMPTY_STRING EMPTY_STRING
+#endif
+
+json_string JSONBase64::json_encode64(const unsigned char * binary, size_t bytes){
+ size_t misaligned = bytes % 3;
+ size_t aligned = (bytes - misaligned) / 3; //divide by three once and inc is faster than add 3 each time
+ json_string result;
+ result.reserve((size_t)(((float)bytes) * 1.37f) + 4);
+
+ //do all of the ones that are 3 byte aligned
+ for (size_t i = 0; i < aligned; ++i){
+ result += chars64[(binary[0] & 0xFC) >> 2];
+ result += chars64[((binary[0] & 0x03) << 4) + ((binary[1] & 0xF0) >> 4)];
+ result += chars64[((binary[1] & 0x0F) << 2) + ((binary[2] & 0xC0) >> 6)];
+ result += chars64[binary[2] & 0x3F];
+ binary += 3;
+ }
+
+ if (misaligned){
+ //copy the rest into a temporary buffer
+ unsigned char temp[3];
+ for (unsigned int i = 0; i < misaligned; ++i){
+ temp[i] = *binary++;
+ }
+ for (unsigned int i = (unsigned int)misaligned; i < 3; ++i){
+ temp[i] = '\0';
+ }
+
+ //now do the final three bytes
+ result += chars64[(temp[0] & 0xFC) >> 2];
+ result += chars64[((temp[0] & 0x03) << 4) + ((temp[1] & 0xF0) >> 4)];
+ if (misaligned == 2){
+ result += chars64[((temp[1] & 0x0F) << 2) + ((temp[2] & 0xC0) >> 6)];
+ result += JSON_TEXT('=');
+ } else {
+ result += JSON_TEXT("==");
+ }
+ }
+ JSON_ASSERT((size_t)(((float)bytes) * 1.37f) + 4 >= result.length(), JSON_TEXT("Didn't reserve enough space for a one-time go"));
+ return result;
+}
+
+inline json_char toBinary(json_char c){
+ if (c == JSON_TEXT('+')){
+ return JSON_TEXT('>');
+ } else if (c == JSON_TEXT('/')){
+ return JSON_TEXT('?');
+ } else if (c < JSON_TEXT(':')){
+ return c + JSON_TEXT('\x04');
+ } else if (c < JSON_TEXT('[')){
+ return c - JSON_TEXT('\x41');
+ }
+ return c - 71;
+}
+
+/*
+ Must be a std::string because it's binary, and chars must be 1 byte
+ */
+std::string JSONBase64::json_decode64(const json_string & encoded){
+ const size_t length = encoded.length();
+ #if defined JSON_DEBUG || defined JSON_SAFE
+ size_t pos = encoded.find_first_not_of(chars64);
+ if (pos != json_string::npos){
+ JSON_ASSERT_SAFE(encoded[pos] == JSON_TEXT('='), JSON_TEXT("Not Base64"), return BASE64_EMPTY_STRING;);
+ if (pos != length - 1){
+ JSON_ASSERT_SAFE(pos == length - 2, JSON_TEXT("Not Base64"), return BASE64_EMPTY_STRING;);
+ JSON_ASSERT_SAFE(encoded[pos + 1] == JSON_TEXT('='), JSON_TEXT("Not Base64"), return BASE64_EMPTY_STRING;);
+ }
+ }
+ #endif
+ const json_char * runner = encoded.c_str();
+ size_t aligned = length / 4; //don't do the last ones as they might be = padding
+ std::string result;
+ if (aligned){
+ --aligned;
+ result.reserve((size_t)((float)length / 1.37) + 1);
+
+ //first do the ones that can not have any padding
+ for (unsigned int i = 0; i < aligned; ++i){
+ const json_char second = toBinary(runner[1]);
+ const json_char third = toBinary(runner[2]);
+ result += (toBinary(runner[0]) << 2) + ((second & 0x30) >> 4);
+ result += ((second & 0xf) << 4) + ((third & 0x3c) >> 2);
+ result += ((third & 0x3) << 6) + toBinary(runner[3]);
+ runner += 4;
+ }
+
+ //now do the ones that might have padding, the first two characters can not be padding, so do them quickly
+ const char second = toBinary(runner[1]);
+ result += (toBinary(runner[0]) << 2) + ((second & 0x30) >> 4);
+ if (runner[2] != '='){ //not two = pads
+ const char third = toBinary(runner[2]);
+ result += ((second & 0xf) << 4) + ((third & 0x3c) >> 2);
+ if (runner[3] != '='){ //no padding
+ result += ((third & 0x3) << 6) + toBinary(runner[3]);
+ }
+ }
+ }
+ return result;
+}
+
+#endif