Extend stat query APIs to explicitly specify if the query is for
a file or directory, allowing just a stat call if a file descriptor
is not needed.
Doing just 'stat' is faster than 'open/fstat/close'.
This has the effect of cutting down system time for validating the input files of a PCH.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169831 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Basic/FileManager.cpp b/lib/Basic/FileManager.cpp
index 5d661b2..3a7bdef 100644
--- a/lib/Basic/FileManager.cpp
+++ b/lib/Basic/FileManager.cpp
@@ -311,7 +311,7 @@
// Check to see if the directory exists.
struct stat StatBuf;
- if (getStatValue(InterndDirName, StatBuf, 0/*directory lookup*/)) {
+ if (getStatValue(InterndDirName, StatBuf, false, 0/*directory lookup*/)) {
// There's no real directory at the given path.
if (!CacheFailure)
SeenDirEntries.erase(DirName);
@@ -376,7 +376,8 @@
// Nope, there isn't. Check to see if the file exists.
int FileDescriptor = -1;
struct stat StatBuf;
- if (getStatValue(InterndFileName, StatBuf, &FileDescriptor)) {
+ if (getStatValue(InterndFileName, StatBuf, true,
+ openFile ? &FileDescriptor : 0)) {
// There's no real file at the given path.
if (!CacheFailure)
SeenFileEntries.erase(Filename);
@@ -444,14 +445,9 @@
"The directory of a virtual file should already be in the cache.");
// Check to see if the file exists. If so, drop the virtual file
- int FileDescriptor = -1;
struct stat StatBuf;
const char *InterndFileName = NamedFileEnt.getKeyData();
- if (getStatValue(InterndFileName, StatBuf, &FileDescriptor) == 0) {
- // If the stat process opened the file, close it to avoid a FD leak.
- if (FileDescriptor != -1)
- close(FileDescriptor);
-
+ if (getStatValue(InterndFileName, StatBuf, true, 0) == 0) {
StatBuf.st_size = Size;
StatBuf.st_mtime = ModificationTime;
UFE = &UniqueRealFiles.getFile(InterndFileName, StatBuf);
@@ -564,18 +560,18 @@
/// false if it's an existent real file. If FileDescriptor is NULL,
/// do directory look-up instead of file look-up.
bool FileManager::getStatValue(const char *Path, struct stat &StatBuf,
- int *FileDescriptor) {
+ bool isFile, int *FileDescriptor) {
// FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
// absolute!
if (FileSystemOpts.WorkingDir.empty())
- return FileSystemStatCache::get(Path, StatBuf, FileDescriptor,
+ return FileSystemStatCache::get(Path, StatBuf, isFile, FileDescriptor,
StatCache.get());
SmallString<128> FilePath(Path);
FixupRelativePath(FilePath);
- return FileSystemStatCache::get(FilePath.c_str(), StatBuf, FileDescriptor,
- StatCache.get());
+ return FileSystemStatCache::get(FilePath.c_str(), StatBuf,
+ isFile, FileDescriptor, StatCache.get());
}
bool FileManager::getNoncachedStatValue(StringRef Path,
diff --git a/lib/Basic/FileSystemStatCache.cpp b/lib/Basic/FileSystemStatCache.cpp
index 875d397..38c4629 100644
--- a/lib/Basic/FileSystemStatCache.cpp
+++ b/lib/Basic/FileSystemStatCache.cpp
@@ -34,21 +34,23 @@
/// path, using the cache to accelerate it if possible. This returns true if
/// the path does not exist or false if it exists.
///
-/// If FileDescriptor is non-null, then this lookup should only return success
-/// for files (not directories). If it is null this lookup should only return
+/// If isFile is true, then this lookup should only return success for files
+/// (not directories). If it is false this lookup should only return
/// success for directories (not files). On a successful file lookup, the
/// implementation can optionally fill in FileDescriptor with a valid
/// descriptor and the client guarantees that it will close it.
bool FileSystemStatCache::get(const char *Path, struct stat &StatBuf,
- int *FileDescriptor, FileSystemStatCache *Cache) {
+ bool isFile, int *FileDescriptor,
+ FileSystemStatCache *Cache) {
LookupResult R;
- bool isForDir = FileDescriptor == 0;
+ bool isForDir = !isFile;
// If we have a cache, use it to resolve the stat query.
if (Cache)
- R = Cache->getStat(Path, StatBuf, FileDescriptor);
- else if (isForDir) {
- // If this is a directory and we have no cache, just go to the file system.
+ R = Cache->getStat(Path, StatBuf, isFile, FileDescriptor);
+ else if (isForDir || !FileDescriptor) {
+ // If this is a directory or a file descriptor is not needed and we have
+ // no cache, just go to the file system.
R = ::stat(Path, &StatBuf) != 0 ? CacheMissing : CacheExists;
} else {
// Otherwise, we have to go to the filesystem. We can always just use
@@ -104,8 +106,8 @@
MemorizeStatCalls::LookupResult
MemorizeStatCalls::getStat(const char *Path, struct stat &StatBuf,
- int *FileDescriptor) {
- LookupResult Result = statChained(Path, StatBuf, FileDescriptor);
+ bool isFile, int *FileDescriptor) {
+ LookupResult Result = statChained(Path, StatBuf, isFile, FileDescriptor);
// Do not cache failed stats, it is easy to construct common inconsistent
// situations if we do, and they are not important for PCH performance (which