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-rw-r--r--Base64/Base64.cpp133
1 files changed, 133 insertions, 0 deletions
diff --git a/Base64/Base64.cpp b/Base64/Base64.cpp
new file mode 100644
index 0000000..62f517f
--- /dev/null
+++ b/Base64/Base64.cpp
@@ -0,0 +1,133 @@
+#include "Base64.h"
+
+const char b64_alphabet[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/";
+
+/* 'Private' declarations */
+inline void a3_to_a4(unsigned char * a4, unsigned char * a3);
+inline void a4_to_a3(unsigned char * a3, unsigned char * a4);
+inline unsigned char b64_lookup(char c);
+
+int base64_encode(char *output, char *input, int inputLen) {
+ int i = 0, j = 0;
+ int encLen = 0;
+ unsigned char a3[3];
+ unsigned char a4[4];
+
+ while(inputLen--) {
+ a3[i++] = *(input++);
+ if(i == 3) {
+ a3_to_a4(a4, a3);
+
+ for(i = 0; i < 4; i++) {
+ output[encLen++] = b64_alphabet[a4[i]];
+ }
+
+ i = 0;
+ }
+ }
+
+ if(i) {
+ for(j = i; j < 3; j++) {
+ a3[j] = '\0';
+ }
+
+ a3_to_a4(a4, a3);
+
+ for(j = 0; j < i + 1; j++) {
+ output[encLen++] = b64_alphabet[a4[j]];
+ }
+
+ while((i++ < 3)) {
+ output[encLen++] = '=';
+ }
+ }
+ output[encLen] = '\0';
+ return encLen;
+}
+
+int base64_decode(char * output, char * input, int inputLen) {
+ int i = 0, j = 0;
+ int decLen = 0;
+ unsigned char a3[3];
+ unsigned char a4[4];
+
+
+ while (inputLen--) {
+ if(*input == '=') {
+ break;
+ }
+
+ a4[i++] = *(input++);
+ if (i == 4) {
+ for (i = 0; i <4; i++) {
+ a4[i] = b64_lookup(a4[i]);
+ }
+
+ a4_to_a3(a3,a4);
+
+ for (i = 0; i < 3; i++) {
+ output[decLen++] = a3[i];
+ }
+ i = 0;
+ }
+ }
+
+ if (i) {
+ for (j = i; j < 4; j++) {
+ a4[j] = '\0';
+ }
+
+ for (j = 0; j <4; j++) {
+ a4[j] = b64_lookup(a4[j]);
+ }
+
+ a4_to_a3(a3,a4);
+
+ for (j = 0; j < i - 1; j++) {
+ output[decLen++] = a3[j];
+ }
+ }
+ output[decLen] = '\0';
+ return decLen;
+}
+
+int base64_enc_len(int plainLen) {
+ int n = plainLen;
+ return (n + 2 - ((n + 2) % 3)) / 3 * 4;
+}
+
+int base64_dec_len(char * input, int inputLen) {
+ int i = 0;
+ int numEq = 0;
+ for(i = inputLen - 1; input[i] == '='; i--) {
+ numEq++;
+ }
+
+ return ((6 * inputLen) / 8) - numEq;
+}
+
+inline void a3_to_a4(unsigned char * a4, unsigned char * a3) {
+ 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);
+}
+
+inline void a4_to_a3(unsigned char * a3, unsigned char * a4) {
+ a3[0] = (a4[0] << 2) + ((a4[1] & 0x30) >> 4);
+ a3[1] = ((a4[1] & 0xf) << 4) + ((a4[2] & 0x3c) >> 2);
+ a3[2] = ((a4[2] & 0x3) << 6) + a4[3];
+}
+
+inline unsigned char b64_lookup(char c) {
+ int i;
+ for(i = 0; i < 64; i++) {
+ if(b64_alphabet[i] == c) {
+ return i;
+ }
+ }
+
+ return -1;
+}