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| author | Chris Lattner <sabre@nondot.org> | 2010-07-12 00:09:55 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2010-07-12 00:09:55 +0000 |
| commit | 1f01109254039f392c559ddc74349b51ec76d4a9 (patch) | |
| tree | 8604dfe21623e57f5b9b8eff13a534da2f6c3303 /lib/System/Unix | |
| parent | 7791080151a5a8bbda073551289469301d006fcb (diff) | |
| download | llvm-1f01109254039f392c559ddc74349b51ec76d4a9.tar.gz llvm-1f01109254039f392c559ddc74349b51ec76d4a9.tar.bz2 llvm-1f01109254039f392c559ddc74349b51ec76d4a9.tar.xz | |
improve Path::makeUnique when mkstemp/mktemp are not available
patch by Lasse Kärkkäinen in PR7404.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108110 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/System/Unix')
| -rw-r--r-- | lib/System/Unix/Path.inc | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/lib/System/Unix/Path.inc b/lib/System/Unix/Path.inc index 185f7fd66b..bc104a32a3 100644 --- a/lib/System/Unix/Path.inc +++ b/lib/System/Unix/Path.inc @@ -888,14 +888,19 @@ Path::makeUnique(bool reuse_current, std::string* ErrMsg) { #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(FNBuffer+offset,"%06u",++FCounter); + // Try to initialize with unique value. + if (FCounter == 0) FCounter = ((unsigned)getpid() & 0xFFFF) << 8; + char* pos = strstr(FNBuffer, "XXXXXX"); + do { + if (++FCounter > 0xFFFFFF) { + return MakeErrMsg(ErrMsg, + path + ": can't make unique filename: too many files"); + } + sprintf(pos, "%06X", FCounter); path = FNBuffer; - } - if (FCounter > 999999) - return MakeErrMsg(ErrMsg, - path + ": can't make unique filename: too many files"); + } while (exists()); + // POSSIBLE SECURITY BUG: An attacker can easily guess the name and exploit + // LLVM. #endif return false; } |