[exim-dev] Change to mime.c

Hi everyone,

maybe some people react like me whenever they take a look at mime.c, the
code is REALLY crude.

A long time ago I started to rewrite it, but never had the time to
finish, because a lot of other things happened. But currently I've some
spare time and looked over the code again and .... it still looks the
same. ;)

So here is a first patch for mime_decode_qp_char, i took it from my old
changes against 4.5X, but AFAICT the code still works the same way.

Over the next days, whenever I find some time, I will send more patches
I just need some more time for testing. ;)

Nico
--- mime.c.org    2006-08-07 13:12:23.000000000 +0200

+++ mime.c    2006-08-07 13:14:08.000000000 +0200
@@ -41,80 +41,41 @@
            0-255 - char to write
 */

-unsigned int mime_qp_hstr_i(uschar *cptr) {
-  unsigned int i, j = 0;
-  while (cptr && *cptr && isxdigit(*cptr)) {
-    i = *cptr++ - '0';
-    if (9 < i) i -= 7;
-    j <<= 4;
-    j |= (i & 0x0f);
-  }
-  return(j);
-}

-uschar *mime_decode_qp_char(uschar *qp_p,int *c) {
- uschar hex[] = {0,0,0};
- int nan = 0;
+uschar *mime_decode_qp_char(uschar *qp_p, int *c) {
uschar *initial_pos = qp_p;

/* advance one char */
qp_p++;

-  REPEAT_FIRST:
-  if ( (*qp_p == '\t') || (*qp_p == ' ') || (*qp_p == '\r') )  {
-    /* tab or whitespace may follow
-       just ignore it, but remember
-       that this is not a valid hex
-       encoding any more */
-    nan = 1;
+  /* Check for two hex digits and decode them */
+  if (isxdigit(*qp_p) && isxdigit(qp_p[1])) {
+    /* Do hex conversion */
+    if (isdigit(*qp_p)) {*c = *qp_p - '0';}
+    else {*c = toupper(*qp_p) - 'A' + 10;};
+    *c <<= 4;
+    if (isdigit(qp_p[1])) {*c |= qp_p[1] - '0';}
+    else {*c |= toupper(qp_p[1]) - 'A' + 10;};
+    return qp_p + 2; 
+  };
+
+  /* tab or whitespace may follow just ignore it */
+  while (*qp_p == '\t' || *qp_p == ' ' || *qp_p == '\r')
     qp_p++;
-    goto REPEAT_FIRST;
-  }
-  else if ( (('0' <= *qp_p) && (*qp_p <= '9')) || (('A' <= *qp_p) && (*qp_p <= 'F'))  || (('a' <= *qp_p) && (*qp_p <= 'f')) ) {
-    /* this is a valid hex char, if nan is unset */
-    if (nan) {
-      /* this is illegal */
-      *c = -2;
-      return initial_pos;
-    }
-    else {
-      hex[0] = *qp_p;
-      qp_p++;
-    };
-  }
-  else if (*qp_p == '\n') {
+
+  if (*qp_p == '\n') {
     /* hit soft line break already, continue */
     *c = -1;
     return qp_p;
-  }
-  else {
-    /* illegal char here */
-    *c = -2;
-    return initial_pos;
   };

-  if ( (('0' <= *qp_p) && (*qp_p <= '9')) || (('A' <= *qp_p) && (*qp_p <= 'F')) || (('a' <= *qp_p) && (*qp_p <= 'f')) ) {
-    if (hex[0] > 0) {
-      hex[1] = *qp_p;
-      /* do hex conversion */
-      *c = mime_qp_hstr_i(hex);
-      qp_p++;
-      return qp_p;
-    }
-    else {
-      /* huh ? */
-      *c = -2;
-      return initial_pos;
-    };
-  }
-  else {
-    /* illegal char */
-    *c = -2;
-    return initial_pos;
-  };
+  /* illegal char here */
+  *c = -2;
+  return initial_pos;
 }

+
uschar *mime_parse_line(uschar *buffer, uschar *data, uschar *encoding, int *num_decoded) {

if (encoding == NULL) {