less shitty variant of mir_base64_decode

git-svn-id: http://svn.miranda-ng.org/main/trunk@5120 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

1 files changed, 15 insertions, 20 deletions

diff --git a/src/mir_core/http.cpp b/src/mir_core/http.cpp
index 03c6f9b91f..5cc95c58bf 100644
--- a/src/mir_core/http.cpp
+++ b/src/mir_core/http.cpp
@@ -97,7 +97,7 @@ MIR_CORE_DLL(char*) mir_base64_encode(const BYTE *input, unsigned inputLen)
 

 /////////////////////////////////////////////////////////////////////////////////////////

 

-static int Base64DecodeTable[] =

+static BYTE Base64DecodeTable[] =

 {

 	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,

 	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,

@@ -122,38 +122,33 @@ MIR_CORE_DLL(void*) mir_base64_decode(const char *input, unsigned *outputLen)
 	if (input == NULL)

 		return NULL;

 

-	size_t i = 0;

-	BYTE chr[3], enc[4];

-

 	size_t length = strlen(input);

 	size_t nLength = (length / 4) * 3;

+	const char *stop = input + length;

 

 	char *output = (char *)mir_alloc(nLength+1);

 	char *p = output;

 

-	while (i < length)

-	{

-		enc[0] = Base64DecodeTable[input[i++]];

-		enc[1] = Base64DecodeTable[input[i++]];

-		enc[2] = Base64DecodeTable[input[i++]];

-		enc[3] = Base64DecodeTable[input[i++]];

-

-		if (enc[0] == -1 || enc[1] == -1) break;

-

-		chr[0] = (enc[0] << 2) | (enc[1] >> 4);

-		chr[1] = ((enc[1] & 15) << 4) | (enc[2] >> 2);

-		chr[2] = ((enc[2] & 3) << 6) | enc[3];

+	while (input < stop) {

+		BYTE e0 = Base64DecodeTable[*input++];

+		BYTE e1 = Base64DecodeTable[*input++];

+		BYTE e2 = Base64DecodeTable[*input++];

+		BYTE e3 = Base64DecodeTable[*input++];

 

-		*p++ = chr[0];

+		if (e0 == (BYTE)-1 || e1 == (BYTE)-1)

+			break;

 

-		if (enc[2] != -1) *p++ = chr[1];

-		if (enc[3] != -1) *p++ = chr[2];

+		*p++ = (e0 << 2) | (e1 >> 4);

+		if (e2 != (BYTE)-1)

+			*p++ = ((e1 & 15) << 4) | (e2 >> 2);

+		if (e3 != (BYTE)-1)

+			*p++ = ((e2 & 3) << 6) | e3;

 	}

 

 	*p = 0;

 

 	if (outputLen != NULL)

-		*outputLen = (unsigned)nLength;

+		*outputLen = p - output;

 

 	return output;

 }