Merge branch '1425-fix-graceful-surrogate-handling'

* 1425-fix-graceful-surrogate-handling:
  Handle invalid UTF-8 byte sequences gracefully by replacing them with 0xFFFD

2 files changed, 17 insertions, 13 deletions

diff --git a/THANKS.in b/THANKS.in
index d82c23d47..b87ffec85 100644
--- a/THANKS.in
+++ b/THANKS.in
@@ -92,6 +92,7 @@ suggesting improvements or submitting changes. Some of these people are:
  * Fedor Indutny <fedor@indutny.com>
  * Tim Blair
  * Tady Walsh <hello@tady.me>
+ * Sam Rijs <recv@awesam.de>
 # Authors from commit 6c976bd and onwards are auto-inserted. If you are merging
 # a commit from a non-committer, you should not add an entry to this file. When
 # `bootstrap` is run, the actual THANKS file will be generated.
diff --git a/src/couchdb/priv/couch_js/utf8.c b/src/couchdb/priv/couch_js/utf8.c
index d60642671..2d23cc204 100644
--- a/src/couchdb/priv/couch_js/utf8.c
+++ b/src/couchdb/priv/couch_js/utf8.c
@@ -66,24 +66,31 @@ enc_charbuf(const jschar* src, size_t srclen, char* dst, size_t* dstlenp)
         c = *src++;
         srclen--;
 
-        if((c >= 0xDC00) && (c <= 0xDFFF)) goto bad_surrogate;
-        
-        if(c < 0xD800 || c > 0xDBFF)
+        if(c <= 0xD7FF || c >= 0xE000)
         {
-            v = c;
+            v = (uint32) c;
         }
-        else
+        else if(c >= 0xD800 && c <= 0xDBFF)
         {
             if(srclen < 1) goto buffer_too_small;
             c2 = *src++;
             srclen--;
-            if ((c2 < 0xDC00) || (c2 > 0xDFFF))
+            if(c2 >= 0xDC00 && c2 <= 0xDFFF)
+            {
+                v = (uint32) (((c - 0xD800) << 10) + (c2 - 0xDC00) + 0x10000);
+            }
+            else
             {
-                c = c2;
-                goto bad_surrogate;
+                // Invalid second half of surrogate pair
+                v = (uint32) 0xFFFD;
             }
-            v = ((c - 0xD800) << 10) + (c2 - 0xDC00) + 0x10000;
         }
+        else
+        {
+            // Invalid first half surrogate pair
+            v = (uint32) 0xFFFD;
+        }
+
         if(v < 0x0080)
         {
             /* no encoding necessary - performance hack */
@@ -109,10 +116,6 @@ enc_charbuf(const jschar* src, size_t srclen, char* dst, size_t* dstlenp)
     *dstlenp = (origDstlen - dstlen);
     return JS_TRUE;
 
-bad_surrogate:
-    *dstlenp = (origDstlen - dstlen);
-    return JS_FALSE;
-
 buffer_too_small:
     *dstlenp = (origDstlen - dstlen);
     return JS_FALSE;