initial commit.

LICENSE

@@ -18,4 +18,4 @@ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
+SOFTWARE.

README.md

@@ -1,2 +1,44 @@
-# arduino_base64
-Binary based (uint8_t) simple Base64 Codec for Arduino.
+# Arduino Base64 Codec
+Binary based simple Base64 Codec for Arduino.
+
+
+# API
+## `void BASE64::encode(const uint8_t* input, char* output, size_t length)`
+**Arguments**
+- `input`: Receives raw data as a binary array.
+- `output`: Base64 encoded string.
+- `length`: Number of bytes of input data.
+
+**Return**
+- Nothing.
+
+**Note**
+- If the input data is a `char*`, cast it to `uint8_t*`.
+
+
+## `size_t BASE64::encodeLength(size_t length)`
+**Arguments**
+- `length`: Number of bytes of input data.
+
+**Return**
+- Number of characters after Base64 encoding.
+
+
+## `void BASE64::decode(const char* input, uint8_t* output)`
+**Arguments**
+- `input`: Receives string data as a base64 encoded.
+- `output`: Raw binary data.
+
+**Return**
+- Nothing.
+
+
+## `size_t BASE64::decodeLength(const char* input)`
+**Arguments**
+- `input`: Receives string data as a base64 encoded.
+
+**Return**
+- Number of bytes after Base64 decoding.
+
+# Disclaimer
+According to MIT License.

examples/decode/decode.ino

@@ -0,0 +1,16 @@
+#include "Arduino.h"
+#include "Base64.h"
+
+void setup(){
+    Serial.begin(115200);
+    while(!Serial);
+
+    const char* encodedData = "Zm9vYmFy";
+
+    uint8_t raw[BASE64::decodeLength(encodedData)];
+    BASE64::decode(encodedData, raw);
+
+    Serial.println((char*)raw);
+}
+
+void loop(){}

examples/encode/encode.ino

@@ -0,0 +1,17 @@
+#include "Arduino.h"
+#include "Base64.h"
+
+void setup(){
+    Serial.begin(115200);
+    while(!Serial);
+
+    const char* rawData = "foobar";
+    size_t rawSize = strlen(rawData);
+
+    char encoded[BASE64::encodeLength(rawSize)];
+    BASE64::encode((const uint8_t*)rawData, encoded, rawSize);
+
+    Serial.println(encoded);
+}
+
+void loop(){}

library.properties

@@ -0,0 +1,9 @@
+name=Base64_Codec
+version=1.0.0
+author=dojyorin
+maintainer=https://github.com/dojyorin
+sentence=Base64 Codec
+paragraph=Binary based simple Base64 Codec.
+category=Other
+url=https://github.com/dojyorin/arduino_base64.git
+architectures=*

src/Base64.cpp

@@ -0,0 +1,132 @@
+#include "Base64.h"
+
+namespace{
+	const char alphaTable[64] = {
+        0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50,
+        0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66,
+        0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76,
+        0x77, 0x78, 0x79, 0x7A, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x2B, 0x2F
+	};
+
+    const uint8_t charTable[128] = {
+        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x3E, 0xFF, 0xFF, 0xFF, 0x3F,
+        0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+        0xFF, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E,
+        0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+        0xFF, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
+        0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    };
+
+	void a3to4(uint8_t* a3, uint8_t* a4){
+		a4[0] = (a3[0] & 0xFC) >> 2;
+		a4[1] = ((a3[0] & 0x03) << 4) + ((a3[1] & 0xF0) >> 4);
+		a4[2] = ((a3[1] & 0x0F) << 2) + ((a3[2] & 0xC0) >> 6);
+		a4[3] = a3[2] & 0x3F;
+	}
+
+	void a4to3(uint8_t* a4, uint8_t* a3){
+		a3[0] = (a4[0] << 2) + ((a4[1] & 0x30) >> 4);
+		a3[1] = ((a4[1] & 0x0F) << 4) + ((a4[2] & 0x3C) >> 2);
+		a3[2] = ((a4[2] & 0x03) << 6) + a4[3];
+	}
+}
+
+void BASE64::encode(const uint8_t* input, char* output, size_t length){
+	uint8_t i = 0;
+	uint8_t a3[3];
+	uint8_t a4[4];
+
+	while(length--){
+		a3[i++] = *input++;
+
+		if(i == 3){
+			a3to4(a3, a4);
+
+			for(i = 0; i < 4; i++){
+				*output++ = alphaTable[a4[i]];
+			}
+
+			i = 0;
+		}
+	}
+
+	if(i){
+		for(uint8_t j = i; j < 3; j++){
+			a3[j] = '\0';
+		}
+
+		a3to4(a3, a4);
+
+		for(uint8_t j = 0; j < i + 1; j++){
+			*output++ = alphaTable[a4[j]];
+		}
+
+		while(i++ < 3){
+			*output++ = '=';
+		}
+	}
+
+	*output = '\0';
+}
+
+size_t BASE64::encodeLength(size_t length){
+	return (length + 2 - ((length + 2) % 3)) / 3 * 4 + 1;
+}
+
+void BASE64::decode(const char* input, uint8_t* output){
+	size_t length = strlen(input);
+	uint8_t i = 0;
+	uint8_t a3[3];
+	uint8_t a4[4];
+
+	while(length--){
+		if(*input == '='){
+			break;
+		}
+
+		a4[i++] = *input++;
+
+		if(i == 4){
+			for(i = 0; i < 4; i++){
+				a4[i] = charTable[a4[i]];
+			}
+
+			a4to3(a4, a3);
+
+			for(i = 0; i < 3; i++){
+				*output++ = a3[i];
+			}
+
+			i = 0;
+		}
+	}
+
+	if(i){
+		for(uint8_t j = i; j < 4; j++){
+			a4[j] = '\0';
+		}
+
+		for(uint8_t j = 0; j < 4; j++){
+			a4[j] = charTable[a4[j]];
+		}
+
+		a4to3(a4, a3);
+
+		for(uint8_t j = 0; j < i - 1; j++){
+			*output++ = a3[j];
+		}
+	}
+}
+
+size_t BASE64::decodeLength(const char* input){
+	size_t length = strlen(input);
+	uint8_t eq = 0;
+
+	for(uint32_t i = length - 1; input[i] == '='; i--){
+		eq++;
+	}
+
+	return 6 * length / 8 - eq;
+}

src/Base64.h

@@ -0,0 +1,14 @@
+#ifndef Base64_Header
+#define Base64_Header
+
+#include "inttypes.h"
+#include "string.h"
+
+namespace BASE64{
+    void encode(const uint8_t* input, char* output, size_t length);
+    size_t encodeLength(size_t length);
+    void decode(const char* input, uint8_t* output);
+    size_t decodeLength(const char* input);
+}
+
+#endif