Fix DestroyDB

Summary:
When DestroyDB() finds a wal file in the DB directory, it assumes it is actually in WAL directory. This can lead to confusion, since it reports IO error when it tries to delete wal file from DB directory. For example: https://ci-builds.fb.com/job/rocksdb_clang_build/296/console

This change will fix our unit tests.

Test Plan: unit tests work

Reviewers: yhchiang, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D32907

db/db_impl.cc

@@ -3885,23 +3885,10 @@ Status DestroyDB(const std::string& dbname, const Options& options) {
   const Options& soptions(SanitizeOptions(dbname, &comparator, options));
   Env* env = soptions.env;
   std::vector<std::string> filenames;
-  std::vector<std::string> archiveFiles;
 
-  std::string archivedir = ArchivalDirectory(dbname);
   // Ignore error in case directory does not exist
   env->GetChildren(dbname, &filenames);
 
-  if (dbname != soptions.wal_dir) {
-    std::vector<std::string> logfilenames;
-    env->GetChildren(soptions.wal_dir, &logfilenames);
-    filenames.insert(filenames.end(), logfilenames.begin(), logfilenames.end());
-    archivedir = ArchivalDirectory(soptions.wal_dir);
-  }
-
-  if (filenames.empty()) {
-    return Status::OK();
-  }
-
   FileLock* lock;
   const std::string lockname = LockFileName(dbname);
   Status result = env->LockFile(lockname, &lock);
@@ -3915,8 +3902,6 @@ Status DestroyDB(const std::string& dbname, const Options& options) {
         Status del;
         if (type == kMetaDatabase) {
           del = DestroyDB(dbname + "/" + filenames[i], options);
-        } else if (type == kLogFile) {
-          del = env->DeleteFile(soptions.wal_dir + "/" + filenames[i]);
         } else {
           del = env->DeleteFile(dbname + "/" + filenames[i]);
         }
@@ -3939,6 +3924,24 @@ Status DestroyDB(const std::string& dbname, const Options& options) {
       }
     }
 
+    std::vector<std::string> walDirFiles;
+    std::string archivedir = ArchivalDirectory(dbname);
+    if (dbname != soptions.wal_dir) {
+      env->GetChildren(soptions.wal_dir, &walDirFiles);
+      archivedir = ArchivalDirectory(soptions.wal_dir);
+    }
+
+    // Delete log files in the WAL dir
+    for (const auto& file : walDirFiles) {
+      if (ParseFileName(file, &number, &type) && type == kLogFile) {
+        Status del = env->DeleteFile(soptions.wal_dir + "/" + file);
+        if (result.ok() && !del.ok()) {
+          result = del;
+        }
+      }
+    }
+
+    std::vector<std::string> archiveFiles;
     env->GetChildren(archivedir, &archiveFiles);
     // Delete archival files.
     for (size_t i = 0; i < archiveFiles.size(); ++i) {

db/db_test.cc

@@ -624,7 +624,7 @@ class DBTest {
         options.db_log_dir = test::TmpDir(env_);
         break;
       case kWalDirAndMmapReads:
-        options.wal_dir = test::TmpDir(env_) + "/wal";
+        options.wal_dir = dbname_ + "/wal";
         // mmap reads should be orthogonal to WalDir setting, so we piggyback to
         // this option config to test mmap reads as well
         options.allow_mmap_reads = true;
@@ -2595,8 +2595,9 @@ TEST(DBTest, IgnoreRecoveredLog) {
     Options options = CurrentOptions();
     options.create_if_missing = true;
     options.merge_operator = MergeOperators::CreateUInt64AddOperator();
-    options.wal_dir = dbname_ + "/logs";
+    options.wal_dir = dbname_ + "/wal";
-    DestroyAndReopen(options);
+    Destroy(options);
+    Reopen(options);
 
     // fill up the DB
     std::string one, two;