update to pcre 7.9

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@13706 d0543943-73ff-0310-b7d9-9358b9ac24b2

libs/pcre/pcre_valid_utf8.c

@@ -6,7 +6,7 @@
 and semantics are as close as possible to those of the Perl 5 language.
 
                        Written by Philip Hazel
-           Copyright (c) 1997-2006 University of Cambridge
+           Copyright (c) 1997-2009 University of Cambridge
 
 -----------------------------------------------------------------------------
 Redistribution and use in source and binary forms, with or without
@@ -42,6 +42,10 @@ POSSIBILITY OF SUCH DAMAGE.
 strings. */
 
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include "pcre_internal.h"
 
 
@@ -55,6 +59,13 @@ that subsequent code can assume it is dealing with a valid string. The check
 can be turned off for maximum performance, but the consequences of supplying
 an invalid string are then undefined.
 
+Originally, this function checked according to RFC 2279, allowing for values in
+the range 0 to 0x7fffffff, up to 6 bytes long, but ensuring that they were in
+the canonical format. Once somebody had pointed out RFC 3629 to me (it
+obsoletes 2279), additional restrictions were applied. The values are now
+limited to be between 0 and 0x0010ffff, no more than 4 bytes long, and the
+subrange 0xd000 to 0xdfff is excluded.
+
 Arguments:
   string       points to the string
   length       length of string, or -1 if the string is zero-terminated
@@ -64,9 +75,10 @@ Returns:       < 0    if the string is a valid UTF-8 string
 */
 
 int
-_pcre_valid_utf8(const uschar *string, int length)
+_pcre_valid_utf8(USPTR string, int length)
 {
-register const uschar *p;
+#ifdef SUPPORT_UTF8
+register USPTR p;
 
 if (length < 0)
   {
@@ -79,32 +91,49 @@ for (p = string; length-- > 0; p++)
   register int ab;
   register int c = *p;
   if (c < 128) continue;
-  if ((c & 0xc0) != 0xc0) return p - string;
-  ab = _pcre_utf8_table4[c & 0x3f];  /* Number of additional bytes */
-  if (length < ab) return p - string;
+  if (c < 0xc0) return p - string;
+  ab = _pcre_utf8_table4[c & 0x3f];     /* Number of additional bytes */
+  if (length < ab || ab > 3) return p - string;
   length -= ab;
 
   /* Check top bits in the second byte */
   if ((*(++p) & 0xc0) != 0x80) return p - string;
 
-  /* Check for overlong sequences for each different length */
+  /* Check for overlong sequences for each different length, and for the
+  excluded range 0xd000 to 0xdfff.  */
+
   switch (ab)
     {
-    /* Check for xx00 000x */
+    /* Check for xx00 000x (overlong sequence) */
+
     case 1:
     if ((c & 0x3e) == 0) return p - string;
     continue;   /* We know there aren't any more bytes to check */
 
-    /* Check for 1110 0000, xx0x xxxx */
+    /* Check for 1110 0000, xx0x xxxx (overlong sequence) or
+                 1110 1101, 1010 xxxx (0xd000 - 0xdfff) */
+
     case 2:
-    if (c == 0xe0 && (*p & 0x20) == 0) return p - string;
+    if ((c == 0xe0 && (*p & 0x20) == 0) ||
+        (c == 0xed && *p >= 0xa0))
+      return p - string;
     break;
 
-    /* Check for 1111 0000, xx00 xxxx */
+    /* Check for 1111 0000, xx00 xxxx (overlong sequence) or
+       greater than 0x0010ffff (f4 8f bf bf) */
+
     case 3:
-    if (c == 0xf0 && (*p & 0x30) == 0) return p - string;
+    if ((c == 0xf0 && (*p & 0x30) == 0) ||
+        (c > 0xf4 ) ||
+        (c == 0xf4 && *p > 0x8f))
+      return p - string;
     break;
 
+#if 0
+    /* These cases can no longer occur, as we restrict to a maximum of four
+    bytes nowadays. Leave the code here in case we ever want to add an option
+    for longer sequences. */
+
     /* Check for 1111 1000, xx00 0xxx */
     case 4:
     if (c == 0xf8 && (*p & 0x38) == 0) return p - string;
@@ -115,6 +144,8 @@ for (p = string; length-- > 0; p++)
     if (c == 0xfe || c == 0xff ||
        (c == 0xfc && (*p & 0x3c) == 0)) return p - string;
     break;
+#endif
+
     }
 
   /* Check for valid bytes after the 2nd, if any; all must start 10 */
@@ -123,6 +154,10 @@ for (p = string; length-- > 0; p++)
     if ((*(++p) & 0xc0) != 0x80) return p - string;
     }
   }
+#else
+(void)(string);  /* Keep picky compilers happy */
+(void)(length);
+#endif
 
 return -1;
 }