From fbb5f5ba1f1427d78677007e019009abecc36120 Mon Sep 17 00:00:00 2001
From: Markus Scherer <markus.icu@gmail.com>
Date: Thu, 12 Sep 2013 00:02:41 +0000
Subject: [PATCH] ICU-10371 fix assertion in
 u_strFromUTF8()/u_strFromUTF8WithSub() code

X-SVN-Rev: 34279
---
 icu4c/source/common/ustrtrns.cpp      |  6 ++++--
 icu4c/source/test/cintltst/custrtrn.c | 13 +++++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/icu4c/source/common/ustrtrns.cpp b/icu4c/source/common/ustrtrns.cpp
index 57cabd58e2a..fbb7b46f309 100644
--- a/icu4c/source/common/ustrtrns.cpp
+++ b/icu4c/source/common/ustrtrns.cpp
@@ -1,7 +1,7 @@
 /*
 ******************************************************************************
 *
-*   Copyright (C) 2001-2012, International Business Machines
+*   Copyright (C) 2001-2013, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 ******************************************************************************
@@ -34,6 +34,8 @@
 #include "ustr_imp.h"
 #include "uassert.h"
 
+#define LENGTHOF(array) (int32_t)(sizeof(array)/sizeof((array)[0]))
+
 U_CAPI UChar* U_EXPORT2 
 u_strFromUTF32WithSub(UChar *dest,
                int32_t destCapacity,
@@ -381,7 +383,7 @@ utf8_nextCharSafeBodyPointer(const uint8_t **ps, const uint8_t *limit, UChar32 c
 
     /* correct sequence - all trail bytes have (b7..b6)==(10)? */
     /* illegal is also set if count>=4 */
-    U_ASSERT(count<sizeof(utf8_minLegal)/sizeof(utf8_minLegal[0]));
+    U_ASSERT(illegal || count<LENGTHOF(utf8_minLegal));
     if(illegal || c<utf8_minLegal[count] || U_IS_SURROGATE(c)) {
         /* error handling */
         /* don't go beyond this sequence */
diff --git a/icu4c/source/test/cintltst/custrtrn.c b/icu4c/source/test/cintltst/custrtrn.c
index 3b347f359fe..847a1f2fe37 100644
--- a/icu4c/source/test/cintltst/custrtrn.c
+++ b/icu4c/source/test/cintltst/custrtrn.c
@@ -846,6 +846,19 @@ static void Test_UChar_UTF8_API(void){
             log_err("error: u_strToUTF8WithSub(no subchar) failed\n");
         }
     }
+    {
+        /*
+         * Test with an illegal lead byte that would be followed by more than 3 trail bytes.
+         * See ticket #10371.
+         */
+        static const char src[1]={ 0xf8 };
+        UChar out16[10];
+        err=U_ZERO_ERROR;
+        u_strFromUTF8(out16, LENGTHOF(out16), NULL, src, 1, &err);
+        if(err!=U_INVALID_CHAR_FOUND) {
+            log_err("error: u_strFromUTF8(5-byte lead byte) failed\n");
+        }
+    }
 }
 
 /* compare if two strings are equal, but match 0xfffd in the second string with anything in the first */