Adding uuencode function

diff --git a/isp_utils.c b/isp_utils.c
index 4f9783f..af702d9 100644 (file)
--- a/isp_utils.c
+++ b/isp_utils.c
@@ -186,22 +186,57 @@ int isp_serial_read(char* buf, unsigned int buf_size, unsigned int min_read)
 /* This might have been taken from a lib, but I hate lib dependencies, and installing
  *  a full window manager (or MTA or MUA for instance) for two functions is not an 
  *  option */
+#define UUENCODE_ADDED_VAL 32
+#define LINE_DATA_LENGTH_MAX 45
+#define LINE_LENGTH_NULL 96
+
 int isp_uu_encode(char* dest, char* src, unsigned int orig_size)
 {
-       int new_size = 0;
+       unsigned int new_size = 0;
+       unsigned int pos = 0;
 
-       while (orig_size--) {
-               if (*src) {
-                       *dest++ = *src++;
-                       new_size++;
-               } else {
+       while (pos < orig_size) {
+               unsigned int line_length = orig_size - pos;
+               unsigned int i = 0;
+               
+               /* Start with line length */
+               if (line_length > LINE_DATA_LENGTH_MAX) {
+                       line_length = LINE_DATA_LENGTH_MAX;
                }
+               dest[new_size] = line_length + UUENCODE_ADDED_VAL;
+               new_size++;
+               
+               /* Encode line */
+               while (i < line_length) {
+                       uint32_t int_triplet = 0;
+                       int j = 0;
+                       
+                       /* Get original triplet (three bytes) */
+                       for (j=0; j<3; j++) {
+                               int_triplet |= ((src[pos + i + j] & 0xFF) << (8 * (2 - j)));
+                               /* if not enougth data, leave it as nul */
+                               if ((i + j) > line_length) {
+                                       break;
+                               }
+                       }
+                       for (j=0; j<4; j++) {
+                               /* Store triplet in four bytes */
+                               dest[new_size + j] = ((int_triplet >> (6 * (3 - j))) & 0x3F);
+                               /* Add offset */
+                               dest[new_size + j] += UUENCODE_ADDED_VAL;
+                       }
+                       i += 3;
+                       new_size += 4;
+               }
+               pos += line_length;
+
+               /* Add \r\n */
+               dest[new_size++] = '\r';
+               dest[new_size++] = '\n';
        }
        return new_size;
 }
 
-#define UUENCODE_ADDED_VAL 32
-#define LINE_LENGTH_NULL 96
 int isp_uu_decode(char* dest, char* src, unsigned int orig_size)
 {
        unsigned int new_size = 0;