From a54177be4b97628e4f90c3690d60a67d6ca3daf9 Mon Sep 17 00:00:00 2001
From: Andy Heninger <andy.heninger@gmail.com>
Date: Tue, 6 May 2014 21:52:26 +0000
Subject: [PATCH] ICU-10865 Thread safety fixes to u_get_stdout().

X-SVN-Rev: 35693
---
 icu4c/source/io/io.vcxproj                 |  2 +-
 icu4c/source/io/io.vcxproj.filters         |  2 +-
 icu4c/source/io/{uprintf.c => uprintf.cpp} | 26 ++++++++++++++--------
 3 files changed, 19 insertions(+), 11 deletions(-)
 rename icu4c/source/io/{uprintf.c => uprintf.cpp} (90%)

diff --git a/icu4c/source/io/io.vcxproj b/icu4c/source/io/io.vcxproj
index bf7c6485e4e..57f392594f0 100644
--- a/icu4c/source/io/io.vcxproj
+++ b/icu4c/source/io/io.vcxproj
@@ -252,7 +252,7 @@
     </ClCompile>
     <ClCompile Include="ufile.c" />
     <ClCompile Include="ufmt_cmn.c" />
-    <ClCompile Include="uprintf.c" />
+    <ClCompile Include="uprintf.cpp" />
     <ClCompile Include="uprntf_p.c" />
     <ClCompile Include="uscanf.c" />
     <ClCompile Include="uscanf_p.c" />
diff --git a/icu4c/source/io/io.vcxproj.filters b/icu4c/source/io/io.vcxproj.filters
index ee1b9a5ea84..34d62c58b7f 100644
--- a/icu4c/source/io/io.vcxproj.filters
+++ b/icu4c/source/io/io.vcxproj.filters
@@ -33,7 +33,7 @@
     <ClCompile Include="ufmt_cmn.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="uprintf.c">
+    <ClCompile Include="uprintf.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
     <ClCompile Include="uprntf_p.c">
diff --git a/icu4c/source/io/uprintf.c b/icu4c/source/io/uprintf.cpp
similarity index 90%
rename from icu4c/source/io/uprintf.c
rename to icu4c/source/io/uprintf.cpp
index 4f9ec18148d..02788adb474 100644
--- a/icu4c/source/io/uprintf.c
+++ b/icu4c/source/io/uprintf.cpp
@@ -1,12 +1,12 @@
 /*
 ******************************************************************************
 *
-*   Copyright (C) 1998-2012, International Business Machines
+*   Copyright (C) 1998-2014, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 ******************************************************************************
 *
-* File uprintf.c
+* File uprintf.cpp
 *
 * Modification History:
 *
@@ -28,14 +28,18 @@
 #include "unicode/udat.h"
 #include "unicode/putil.h"
 
+#include "cmemory.h"
+#include "locbund.h"
+#include "mutex.h"
+#include "uassert.h"
 #include "uprintf.h"
 #include "ufile.h"
 #include "ucln_io.h"
-#include "locbund.h"
 
-#include "cmemory.h"
+U_NAMESPACE_USE
 
 static UFILE *gStdOut = NULL;
+static UInitOnce gStdOutInitOnce = U_INITONCE_INITIALIZER;
 
 static UBool U_CALLCONV uprintf_cleanup(void)
 {
@@ -43,16 +47,20 @@ static UBool U_CALLCONV uprintf_cleanup(void)
         u_fclose(gStdOut);
         gStdOut = NULL;
     }
+    gStdOutInitOnce.reset();
     return TRUE;
 }
 
+static void U_CALLCONV u_stdout_init() {
+    U_ASSERT(gStdOut ==  NULL);
+    gStdOut = u_finit(stdout, NULL, NULL);
+    ucln_io_registerCleanup(UCLN_IO_PRINTF, &uprintf_cleanup);
+}
+
 U_CAPI UFILE * U_EXPORT2
 u_get_stdout()
 {
-    if (gStdOut == NULL) {
-        gStdOut = u_finit(stdout, NULL, NULL);
-        ucln_io_registerCleanup(UCLN_IO_PRINTF, &uprintf_cleanup);
-    }
+    umtx_initOnce(gStdOutInitOnce, &u_stdout_init);
     return gStdOut;
 }
 
@@ -161,7 +169,7 @@ u_vfprintf(    UFILE        *f,
     int32_t count;
     UChar *pattern;
     UChar buffer[UFMT_DEFAULT_BUFFER_SIZE];
-    int32_t size = (int32_t)strlen(patternSpecification) + 1;
+    size_t size = strlen(patternSpecification) + 1;
 
     /* convert from the default codepage to Unicode */
     if (size >= MAX_UCHAR_BUFFER_SIZE(buffer)) {