Migrate UnixGlob to Path#statIfFound() instead of #statNullable(). The latter swallows all filesystem failures, and does not disambiguate missing files from filesystem problems.

The syscall cache now tracks IOExceptions if they are present, just as it does with readdir().

RELNOTES: None
PiperOrigin-RevId: 153185433

1 files changed, 18 insertions, 10 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PerBuildSyscallCache.java b/src/main/java/com/google/devtools/build/lib/skyframe/PerBuildSyscallCache.java
index 646d6093dd..d9eb4506a6 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PerBuildSyscallCache.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PerBuildSyscallCache.java
@@ -30,13 +30,14 @@ import java.util.Collection;
  */
 public class PerBuildSyscallCache implements UnixGlob.FilesystemCalls {
 
-  private final LoadingCache<Pair<Path, Symlinks>, FileStatus> statCache;
+  private final LoadingCache<Pair<Path, Symlinks>, Pair<FileStatus, IOException>> statCache;
   private final LoadingCache<Pair<Path, Symlinks>, Pair<Collection<Dirent>, IOException>>
       readdirCache;
 
   private static final FileStatus NO_STATUS = new FakeFileStatus();
 
-  private PerBuildSyscallCache(LoadingCache<Pair<Path, Symlinks>, FileStatus> statCache,
+  private PerBuildSyscallCache(
+      LoadingCache<Pair<Path, Symlinks>, Pair<FileStatus, IOException>> statCache,
       LoadingCache<Pair<Path, Symlinks>, Pair<Collection<Dirent>, IOException>> readdirCache) {
     this.statCache = statCache;
     this.readdirCache = readdirCache;
@@ -104,9 +105,12 @@ public class PerBuildSyscallCache implements UnixGlob.FilesystemCalls {
   }
 
   @Override
-  public FileStatus statNullable(Path path, Symlinks symlinks) {
-    FileStatus status = statCache.getUnchecked(Pair.of(path, symlinks));
-    return (status == NO_STATUS) ? null : status;
+  public FileStatus statIfFound(Path path, Symlinks symlinks) throws IOException {
+    Pair<FileStatus, IOException> status = statCache.getUnchecked(Pair.of(path, symlinks));
+    if (status.getFirst() != null) {
+      return (status.getFirst() == NO_STATUS) ? null : status.getFirst();
+    }
+    throw status.getSecond();
   }
 
   public void clear() {
@@ -162,12 +166,16 @@ public class PerBuildSyscallCache implements UnixGlob.FilesystemCalls {
    * Input: (path, following_symlinks)
    * Output: FileStatus
    */
-  private static CacheLoader<Pair<Path, Symlinks>, FileStatus> newStatLoader() {
-    return new CacheLoader<Pair<Path, Symlinks>, FileStatus>() {
+  private static CacheLoader<Pair<Path, Symlinks>, Pair<FileStatus, IOException>> newStatLoader() {
+    return new CacheLoader<Pair<Path, Symlinks>, Pair<FileStatus, IOException>>() {
         @Override
-        public FileStatus load(Pair<Path, Symlinks> p) {
-          FileStatus f = p.first.statNullable(p.second);
-          return (f == null) ? NO_STATUS : f;
+        public Pair<FileStatus, IOException> load(Pair<Path, Symlinks> p) {
+          try {
+            FileStatus f = p.first.statIfFound(p.second);
+            return Pair.of((f == null) ? NO_STATUS : f, null);
+          } catch (IOException e) {
+            return Pair.of(null, e);
+          }
         }
       };
   }