Make hexadecimal and base64 routines behave the same.

[meshlink] / src / utils.c

diff --git a/src/utils.c b/src/utils.c
index c58f8ca8ddd9857d8c35a00c99f633dcd4624596..ab426ab7e7b3715d83beca1b1ee2bbeed991ccf1 100644 (file)
--- a/src/utils.c
+++ b/src/utils.c
@@ -46,25 +46,29 @@ static int charb64decode(char c) {
                return 63;
 }
 
-void hex2bin(char *src, char *dst, int length) {
+int hex2bin(char *src, char *dst, int length) {
        int i;
-       for(i = 0; i < length; i++)
+       for(i = 0; i < length && src[i * 2] && src[i * 2 + 1]; i++)
                dst[i] = charhex2bin(src[i * 2]) * 16 + charhex2bin(src[i * 2 + 1]);
+       return i;
 }
 
-void bin2hex(char *src, char *dst, int length) {
+int bin2hex(char *src, char *dst, int length) {
        int i;
        for(i = length - 1; i >= 0; i--) {
                dst[i * 2 + 1] = hexadecimals[(unsigned char) src[i] & 15];
                dst[i * 2] = hexadecimals[(unsigned char) src[i] >> 4];
        }
+       dst[length * 2] = 0;
+       return length * 2;
 }
 
-int b64decode(const char *src, char *dst, int length) {
+int b64decode(char *src, char *dst, int length) {
+       int i;
        uint32_t triplet = 0;
        unsigned char *udst = dst;
 
-       for(int i = 0; i < length; i++) {
+       for(i = 0; i < length / 3 * 4 && src[i]; i++) {
                triplet |= charb64decode(src[i]) << (6 * (i & 3));
                if((i & 3) == 3) {
                        udst[0] = triplet & 0xff; triplet >>= 8;
@@ -74,49 +78,57 @@ int b64decode(const char *src, char *dst, int length) {
                        udst += 3;
                }
        }
-       if((length & 3) == 3) {
+       if((i & 3) == 3) {
                udst[0] = triplet & 0xff; triplet >>= 8;
                udst[1] = triplet & 0xff;
-               return length / 4 * 3 + 2;
-       } else if((length & 3) == 2) {
+               return i / 4 * 3 + 2;
+       } else if((i & 3) == 2) {
                udst[0] = triplet & 0xff;
-               return length / 4 * 3 + 1;
+               return i / 4 * 3 + 1;
        } else {
-               return length / 4 * 3;
+               return i / 4 * 3;
        }
 }
 
-int b64encode(const char *src, char *dst, int length) {
+int b64encode(char *src, char *dst, int length) {
        uint32_t triplet;
        const unsigned char *usrc = src;
-       int origlen = length;
-
-       while(length > 0) {
-               if(length >= 3) {
-                       triplet = usrc[0] | usrc[1] << 8 | usrc[2] << 16;
-                       dst[0] = base64imals[triplet & 63]; triplet >>= 6;
-                       dst[1] = base64imals[triplet & 63]; triplet >>= 6;
-                       dst[2] = base64imals[triplet & 63]; triplet >>= 6;
-                       dst[3] = base64imals[triplet];
-                       dst += 4; usrc += 3; length -= 3;
-               } else if(length >=2) {
-                       triplet = usrc[0] | usrc[1] << 8;
-                       dst[0] = base64imals[triplet & 63]; triplet >>= 6;
-                       dst[1] = base64imals[triplet & 63]; triplet >>= 6;
-                       dst[2] = base64imals[triplet];
-                       dst[3] = 0;
-                       return origlen / 3 * 4 + 3;
-               } else {
-                       triplet = usrc[0];
-                       dst[0] = base64imals[triplet & 63]; triplet >>= 6;
-                       dst[1] = base64imals[triplet];
-                       dst[2] = 0;
-                       return origlen / 3 * 4 + 2;
-               }
+       int si = length / 3 * 3;
+       int di = length / 3 * 4;
+
+       switch(length % 3) {
+               case 2: 
+                       triplet = usrc[si] | usrc[si + 1] << 8;
+                       dst[di] = base64imals[triplet & 63]; triplet >>= 6;
+                       dst[di + 1] = base64imals[triplet & 63]; triplet >>= 6;
+                       dst[di + 2] = base64imals[triplet];
+                       dst[di + 3] = 0;
+                       length = di + 2;
+                       break;
+               case 1:
+                       triplet = usrc[si];
+                       dst[di] = base64imals[triplet & 63]; triplet >>= 6;
+                       dst[di + 1] = base64imals[triplet];
+                       dst[di + 2] = 0;
+                       length = di + 1;
+                       break;
+               default:
+                       dst[di] = 0;
+                       length = di;
+                       break;
+       }
+
+       while(si > 0) {
+               di -= 4;
+               si -= 3;
+               triplet = usrc[si] | usrc[si + 1] << 8 | usrc[si + 2] << 16;
+               dst[di] = base64imals[triplet & 63]; triplet >>= 6;
+               dst[di + 1] = base64imals[triplet & 63]; triplet >>= 6;
+               dst[di + 2] = base64imals[triplet & 63]; triplet >>= 6;
+               dst[di + 3] = base64imals[triplet];
        }
 
-       *dst = 0;
-       return origlen / 4 * 3;
+       return length;
 }
 
 #if defined(HAVE_MINGW) || defined(HAVE_CYGWIN)