X-Git-Url: https://code.citadel.org/?p=citadel.git;a=blobdiff_plain;f=libcitadel%2Flib%2Fb64%2Fcencode.c;fp=libcitadel%2Flib%2Fb64%2Fcencode.c;h=e440f378437f08b31e91953d3147d8855bdf99b6;hp=0000000000000000000000000000000000000000;hb=4032a9c4c69d6bec1cf7ed922f869d76617487ae;hpb=4eae28a9f066cdd025cefceda2de3fbbccfc8303

diff --git a/libcitadel/lib/b64/cencode.c b/libcitadel/lib/b64/cencode.c
new file mode 100644
index 000000000..e440f3784
--- /dev/null
+++ b/libcitadel/lib/b64/cencode.c
@@ -0,0 +1,99 @@
+/*
+cencoder.c - c source to a base64 encoding algorithm implementation
+
+This is part of the libb64 project, and has been placed in the public domain.
+For details, see http://sourceforge.net/projects/libb64
+*/
+
+#include "b64/cencode.h"
+
+void base64_init_encodestate(base64_encodestate* state_in)
+{
+	state_in->step = step_A;
+	state_in->result = 0;
+}
+
+char base64_encode_value(char value_in)
+{
+	static const char* encoding = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+	if (value_in > 63) return '=';
+	return encoding[(int)value_in];
+}
+
+int base64_encode_block(const char* plaintext_in, int length_in, char* code_out, base64_encodestate* state_in)
+{
+	const char* plainchar = plaintext_in;
+	const char* const plaintextend = plaintext_in + length_in;
+	char* codechar = code_out;
+	char result;
+	char fragment;
+	
+	result = state_in->result;
+	
+	switch (state_in->step)
+	{
+		while (1)
+		{
+	case step_A:
+			if (plainchar == plaintextend)
+			{
+				state_in->result = result;
+				state_in->step = step_A;
+				return codechar - code_out;
+			}
+			fragment = *plainchar++;
+			result = (fragment & 0x0fc) >> 2;
+			*codechar++ = base64_encode_value(result);
+			result = (fragment & 0x003) << 4;
+	case step_B:
+			if (plainchar == plaintextend)
+			{
+				state_in->result = result;
+				state_in->step = step_B;
+				return codechar - code_out;
+			}
+			fragment = *plainchar++;
+			result |= (fragment & 0x0f0) >> 4;
+			*codechar++ = base64_encode_value(result);
+			result = (fragment & 0x00f) << 2;
+	case step_C:
+			if (plainchar == plaintextend)
+			{
+				state_in->result = result;
+				state_in->step = step_C;
+				return codechar - code_out;
+			}
+			fragment = *plainchar++;
+			result |= (fragment & 0x0c0) >> 6;
+			*codechar++ = base64_encode_value(result);
+			result  = (fragment & 0x03f) >> 0;
+			*codechar++ = base64_encode_value(result);
+		}
+	}
+	/* control should not reach here */
+	return codechar - code_out;
+}
+
+int base64_encode_blockend(char* code_out, base64_encodestate* state_in)
+{
+	char* codechar = code_out;
+	
+	switch (state_in->step)
+	{
+	case step_B:
+		*codechar++ = base64_encode_value(state_in->result);
+		*codechar++ = '=';
+		*codechar++ = '=';
+		break;
+	case step_C:
+		*codechar++ = base64_encode_value(state_in->result);
+		*codechar++ = '=';
+		break;
+	case step_A:
+		break;
+	}
+	*codechar++ = '\n';
+	
+	return codechar - code_out;
+}
+