-Path
-Path::GetTemporaryDirectory(std::string *ErrMsg) {
-#if defined(HAVE_MKDTEMP)
- // The best way is with mkdtemp but that's not available on many systems,
- // Linux and FreeBSD have it. Others probably won't.
- char pathname[] = "/tmp/llvm_XXXXXX";
- if (0 == mkdtemp(pathname)) {
- MakeErrMsg(ErrMsg,
- std::string(pathname) + ": can't create temporary directory");
- return Path();
- }
- return Path(pathname);
-#elif defined(HAVE_MKSTEMP)
- // If no mkdtemp is available, mkstemp can be used to create a temporary file
- // which is then removed and created as a directory. We prefer this over
- // mktemp because of mktemp's inherent security and threading risks. We still
- // have a slight race condition from the time the temporary file is created to
- // the time it is re-created as a directoy.
- char pathname[] = "/tmp/llvm_XXXXXX";
- int fd = 0;
- if (-1 == (fd = mkstemp(pathname))) {
- MakeErrMsg(ErrMsg,
- std::string(pathname) + ": can't create temporary directory");
- return Path();
- }
- ::close(fd);
- ::unlink(pathname); // start race condition, ignore errors
- if (-1 == ::mkdir(pathname, S_IRWXU)) { // end race condition
- MakeErrMsg(ErrMsg,
- std::string(pathname) + ": can't create temporary directory");
- return Path();
- }
- return Path(pathname);
-#elif defined(HAVE_MKTEMP)
- // If a system doesn't have mkdtemp(3) or mkstemp(3) but it does have
- // mktemp(3) then we'll assume that system (e.g. AIX) has a reasonable
- // implementation of mktemp(3) and doesn't follow BSD 4.3's lead of replacing
- // the XXXXXX with the pid of the process and a letter. That leads to only
- // twenty six temporary files that can be generated.
- char pathname[] = "/tmp/llvm_XXXXXX";
- char *TmpName = ::mktemp(pathname);
- if (TmpName == 0) {
- MakeErrMsg(ErrMsg,
- std::string(TmpName) + ": can't create unique directory name");
- return Path();
- }
- if (-1 == ::mkdir(TmpName, S_IRWXU)) {
- MakeErrMsg(ErrMsg,
- std::string(TmpName) + ": can't create temporary directory");
- return Path();
- }
- return Path(TmpName);
-#else
- // This is the worst case implementation. tempnam(3) leaks memory unless its
- // on an SVID2 (or later) system. On BSD 4.3 it leaks. tmpnam(3) has thread
- // issues. The mktemp(3) function doesn't have enough variability in the
- // temporary name generated. So, we provide our own implementation that
- // increments an integer from a random number seeded by the current time. This
- // should be sufficiently unique that we don't have many collisions between
- // processes. Generally LLVM processes don't run very long and don't use very
- // many temporary files so this shouldn't be a big issue for LLVM.
- static time_t num = ::time(0);
- char pathname[MAXPATHLEN];
- do {
- num++;
- sprintf(pathname, "/tmp/llvm_%010u", unsigned(num));
- } while ( 0 == access(pathname, F_OK ) );
- if (-1 == ::mkdir(pathname, S_IRWXU)) {
- MakeErrMsg(ErrMsg,
- std::string(pathname) + ": can't create temporary directory");
- return Path();
- }
- return Path(pathname);
-#endif