From f904dc9003534aeccb5a94429a439a83e8f9472f Mon Sep 17 00:00:00 2001
From: Michael Ow <mow@svn.icu-project.org>
Date: Wed, 1 Oct 2008 21:17:55 +0000
Subject: [PATCH] ICU-6554 Add releasing of allocated memory when uprv_tzname
 is called.

X-SVN-Rev: 24698
---
 icu4c/source/common/putil.c    | 14 ++++++++++++++
 icu4c/source/common/putilimp.h |  8 +++++++-
 icu4c/source/i18n/timezone.cpp |  4 ++++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/icu4c/source/common/putil.c b/icu4c/source/common/putil.c
index 88c51f32ff..d31d24d555 100644
--- a/icu4c/source/common/putil.c
+++ b/icu4c/source/common/putil.c
@@ -761,6 +761,7 @@ static const char* remapShortTimeZone(const char *stdID, const char *dstID, int3
 static char* defaultTZBuffer = NULL;
 static int64_t defaultTZFileSize = 0;
 static FILE* defaultTZFilePtr = NULL;
+static UBool defaultTZstatus = FALSE;
 /*
  * This method compares the two files given to see if they are a match.
  * It is currently use to compare two TZ files.
@@ -937,6 +938,7 @@ uprv_tzname(int n)
             defaultTZFileSize = 0;
 
             if (gTimeZoneBufferPtr != NULL && isValidOlsonID(gTimeZoneBufferPtr)) {
+                defaultTZstatus = TRUE;
                 return gTimeZoneBufferPtr;
             }
 #endif
@@ -980,6 +982,18 @@ uprv_tzname(int n)
 #endif
 }
 
+U_CAPI void U_EXPORT2
+uprv_free_tzname(void)
+{
+    /* Only care if memory allocation due to searching for system timezone file. */
+    if (defaultTZstatus == TRUE) {
+        uprv_free(gTimeZoneBufferPtr);
+        gTimeZoneBufferPtr = NULL;
+        defaultTZstatus = FALSE;
+    }
+}
+
+
 /* Get and set the ICU data directory --------------------------------------- */
 
 static char *gDataDirectory = NULL;
diff --git a/icu4c/source/common/putilimp.h b/icu4c/source/common/putilimp.h
index c516821e84..a9e31d0fa0 100644
--- a/icu4c/source/common/putilimp.h
+++ b/icu4c/source/common/putilimp.h
@@ -1,7 +1,7 @@
 /*
 ******************************************************************************
 *
-*   Copyright (C) 1997-2006, International Business Machines
+*   Copyright (C) 1997-2008, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 ******************************************************************************
@@ -211,6 +211,12 @@ U_INTERNAL int32_t  U_EXPORT2 uprv_timezone(void);
  */
 U_INTERNAL const char* U_EXPORT2 uprv_tzname(int n);
 
+/**
+ * If needed, frees the allocated pointer when tzname is called.
+ * @internal
+ */
+U_INTERNAL void  U_EXPORT2 uprv_free_tzname(void);
+
 /**
  * Get UTC (GMT) time measured in milliseconds since 0:00 on 1/1/1970.
  * @return the UTC time measured in milliseconds 
diff --git a/icu4c/source/i18n/timezone.cpp b/icu4c/source/i18n/timezone.cpp
index 5a75b76ad0..aeaa7c3dc5 100644
--- a/icu4c/source/i18n/timezone.cpp
+++ b/icu4c/source/i18n/timezone.cpp
@@ -420,6 +420,10 @@ TimeZone::TimeZone(const UnicodeString &id)
 
 TimeZone::~TimeZone()
 {
+    /* When uprv_tzname() is called, memory might have been
+       allocated for the default timezone name. Release this
+       when the timezone object is deleted. */
+    uprv_free_tzname();
 }
 
 // -------------------------------------