From 72bdd4ca07c9353c76ae12a73532f3b2747a8c42 Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Mon, 19 Apr 2010 15:54:44 +0000
Subject: [PATCH] Revert 91528 and use a std::vector instead, fixing an abuse
 of std::string.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101781 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/System/Unix/Path.inc | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/lib/System/Unix/Path.inc b/lib/System/Unix/Path.inc
index 52253b30a57..a0bfe295223 100644
--- a/lib/System/Unix/Path.inc
+++ b/lib/System/Unix/Path.inc
@@ -16,6 +16,7 @@
 //===          is guaranteed to work on *all* UNIX variants.
 //===----------------------------------------------------------------------===//
 
+#include "llvm/ADT/SmallVector.h"
 #include "Unix.h"
 #if HAVE_SYS_STAT_H
 #include <sys/stat.h>
@@ -858,15 +859,20 @@ Path::makeUnique(bool reuse_current, std::string* ErrMsg) {
 
   // Append an XXXXXX pattern to the end of the file for use with mkstemp,
   // mktemp or our own implementation.
-  std::string Buf(path);
+  // This uses std::vector instead of SmallVector to avoid a dependence on
+  // libSupport. And performance isn't critical here.
+  std::vector<char> Buf;
+  Buf.resize(path.size()+8);
+  char *FNBuffer = Buf.data();
+    path.copy(FNBuffer,path.size());
   if (isDirectory())
-    Buf += "/XXXXXX";
+    strcpy(FNBuffer+path.size(), "/XXXXXX");
   else
-    Buf += "-XXXXXX";
+    strcpy(FNBuffer+path.size(), "-XXXXXX");
 
 #if defined(HAVE_MKSTEMP)
   int TempFD;
-  if ((TempFD = mkstemp((char*)Buf.c_str())) == -1)
+  if ((TempFD = mkstemp(FNBuffer)) == -1)
     return MakeErrMsg(ErrMsg, path + ": can't make unique filename");
 
   // We don't need to hold the temp file descriptor... we will trust that no one
@@ -874,21 +880,21 @@ Path::makeUnique(bool reuse_current, std::string* ErrMsg) {
   close(TempFD);
 
   // Save the name
-  path = Buf;
+  path = FNBuffer;
 #elif defined(HAVE_MKTEMP)
   // If we don't have mkstemp, use the old and obsolete mktemp function.
-  if (mktemp(Buf.c_str()) == 0)
+  if (mktemp(FNBuffer) == 0)
     return MakeErrMsg(ErrMsg, path + ": can't make unique filename");
 
   // Save the name
-  path = Buf;
+  path = FNBuffer;
 #else
   // Okay, looks like we have to do it all by our lonesome.
   static unsigned FCounter = 0;
   unsigned offset = path.size() + 1;
-  while (FCounter < 999999 && exists()) {
-    sprintf(Buf.data()+offset, "%06u", ++FCounter);
-    path = Buf;
+  while ( FCounter < 999999 && exists()) {
+    sprintf(FNBuffer+offset,"%06u",++FCounter);
+    path = FNBuffer;
   }
   if (FCounter > 999999)
     return MakeErrMsg(ErrMsg,