Additional bug fixing for not creating zero-byte object

src/cache.cpp

@@ -100,7 +100,9 @@ inline bool IsExpireStatCacheTime(const struct timespec& ts, const time_t& expir
 {
     struct timespec nowts;
     SetStatCacheTime(nowts);
-    return ((ts.tv_sec + expire) < nowts.tv_sec);
+    nowts.tv_sec -= expire;
+
+    return (0 < CompareStatCacheTime(nowts, ts));
 }
 
 //
@@ -258,7 +260,7 @@ bool StatCache::GetStat(const std::string& key, struct stat* pst, headers_t* met
 
     if(iter != stat_cache.end() && (*iter).second){
         stat_cache_entry* ent = (*iter).second;
-        if(!IsExpireTime || !IsExpireStatCacheTime(ent->cache_date, ExpireTime)){
+        if(0 < ent->notruncate || !IsExpireTime || !IsExpireStatCacheTime(ent->cache_date, ExpireTime)){
             if(ent->noobjcache){
                 if(!IsCacheNoObject){
                     // need to delete this cache.
@@ -343,7 +345,8 @@ bool StatCache::IsNoObjectCache(const std::string& key, bool overcheck)
     }
 
     if(iter != stat_cache.end() && (*iter).second) {
-        if(!IsExpireTime || !IsExpireStatCacheTime((*iter).second->cache_date, ExpireTime)){
+        stat_cache_entry* ent = (*iter).second;
+        if(0 < ent->notruncate || !IsExpireTime || !IsExpireStatCacheTime((*iter).second->cache_date, ExpireTime)){
             if((*iter).second->noobjcache){
                 // noobjcache = true means no object.
                 SetStatCacheTime((*iter).second->cache_date);
@@ -434,6 +437,47 @@ bool StatCache::AddStat(const std::string& key, headers_t& meta, bool forcedir,
     return true;
 }
 
+// [NOTE]
+// Updates only meta data if cached data exists.
+// And when these are updated, it also updates the cache time.
+//
+bool StatCache::UpdateMetaStats(const std::string& key, headers_t& meta)
+{
+    if(CacheSize < 1){
+        return true;
+    }
+    S3FS_PRN_INFO3("update stat cache entry[path=%s]", key.c_str());
+
+    AutoLock lock(&StatCache::stat_cache_lock);
+    stat_cache_t::iterator iter = stat_cache.find(key);
+    if(stat_cache.end() == iter || !(iter->second)){
+        return true;
+    }
+    stat_cache_entry* ent = iter->second;
+
+    // update only meta keys
+    for(headers_t::iterator metaiter = meta.begin(); metaiter != meta.end(); ++metaiter){
+        std::string tag   = lower(metaiter->first);
+        std::string value = metaiter->second;
+        if(tag == "content-type"){
+            ent->meta[metaiter->first] = value;
+        }else if(tag == "content-length"){
+            ent->meta[metaiter->first] = value;
+        }else if(tag == "etag"){
+            ent->meta[metaiter->first] = value;
+        }else if(tag == "last-modified"){
+            ent->meta[metaiter->first] = value;
+        }else if(is_prefix(tag.c_str(), "x-amz")){
+            ent->meta[tag] = value;      // key is lower case for "x-amz"
+        }
+    }
+
+    // Update time.
+    SetStatCacheTime(ent->cache_date);
+
+    return true;
+}
+
 bool StatCache::AddNoObjectCache(const std::string& key)
 {
     if(!IsCacheNoObject){

src/cache.h

@@ -158,6 +158,9 @@ class StatCache
         // Add stat cache
         bool AddStat(const std::string& key, headers_t& meta, bool forcedir = false, bool no_truncate = false);
 
+        // Update meta stats
+        bool UpdateMetaStats(const std::string& key, headers_t& meta);
+
         // Change no truncate flag
         void ChangeNoTruncateFlag(const std::string& key, bool no_truncate);
 

src/s3fs.cpp

@@ -385,7 +385,6 @@ static int get_object_attribute(const char* path, struct stat* pstbuf, headers_t
         strpath += "/";
     }
     if(StatCache::getStatCacheData()->GetStat(strpath, pstat, pheader, overcheck, pisforce)){
-        StatCache::getStatCacheData()->ChangeNoTruncateFlag(strpath, add_no_truncate_cache);
         return 0;
     }
     if(StatCache::getStatCacheData()->IsNoObjectCache(strpath)){
@@ -980,7 +979,16 @@ static int s3fs_create(const char* _path, mode_t mode, struct fuse_file_info* fi
     meta["x-amz-meta-atime"] = str(now);
     meta["x-amz-meta-mtime"] = str(now);
     meta["x-amz-meta-ctime"] = str(now);
-    if(!StatCache::getStatCacheData()->AddStat(path, meta)){
+
+    // [NOTE] set no_truncate flag
+    // At this point, the file has not been created(uploaded) and
+    // the data is only present in the Stats cache.
+    // The Stats cache should not be deleted automatically by
+    // timeout. If this stats is deleted, s3fs will try to get it
+    // from the server with a Head request and will get an
+    // unexpected error because the result object does not exist.
+    //
+    if(!StatCache::getStatCacheData()->AddStat(path, meta, false, true)){
         return -EIO;
     }
 
@@ -1066,9 +1074,9 @@ static int s3fs_unlink(const char* _path)
     }
     S3fsCurl s3fscurl;
     result = s3fscurl.DeleteRequest(path);
-    FdManager::DeleteCacheFile(path);
     StatCache::getStatCacheData()->DelStat(path);
     StatCache::getStatCacheData()->DelSymlink(path);
+    FdManager::DeleteCacheFile(path);
     S3FS_MALLOCTRIM(0);
 
     return result;
@@ -1671,6 +1679,9 @@ static int s3fs_chmod(const char* _path, mode_t mode)
                 // then the meta is pending and accumulated to be put after the upload is complete.
                 S3FS_PRN_INFO("meta pending until upload is complete");
                 need_put_header = false;
+
+                // If there is data in the Stats cache, update the Stats cache.
+                StatCache::getStatCacheData()->UpdateMetaStats(strpath, updatemeta);
             }
         }
         if(need_put_header){
@@ -1845,6 +1856,9 @@ static int s3fs_chown(const char* _path, uid_t uid, gid_t gid)
                 // then the meta is pending and accumulated to be put after the upload is complete.
                 S3FS_PRN_INFO("meta pending until upload is complete");
                 need_put_header = false;
+
+                // If there is data in the Stats cache, update the Stats cache.
+                StatCache::getStatCacheData()->UpdateMetaStats(strpath, updatemeta);
             }
         }
         if(need_put_header){
@@ -2026,6 +2040,9 @@ static int s3fs_utimens(const char* _path, const struct timespec ts[2])
                 need_put_header = false;
                 ent->SetHoldingMtime(ts[1]);     // ts[1] is mtime
 
+                // If there is data in the Stats cache, update the Stats cache.
+                StatCache::getStatCacheData()->UpdateMetaStats(strpath, updatemeta);
+
             }else{
                 S3FS_PRN_INFO("meta is not pending, but need to keep current mtime.");
 
@@ -2223,16 +2240,21 @@ static int s3fs_open(const char* _path, struct fuse_file_info* fi)
         return -EACCES;
     }
 
-    // clear stat for reading fresh stat.
+    // [NOTE]
-    // (if object stat is changed, we refresh it. then s3fs gets always
+    // Delete the Stats cache only if the file is not open.
-    // stat when s3fs open the object).
+    // If the file is open, the stats cache will not be deleted as
+    // there are cases where the object does not exist on the server
+    // and only the Stats cache exists.
+    //
     if(StatCache::getStatCacheData()->HasStat(path)){
-        // flush any dirty data so that subsequent stat gets correct size
+        AutoFdEntity autoent_local;
+        if(NULL == autoent_local.ExistOpen(path, -1, true)){
             if((result = s3fs_flush(_path, fi)) != 0){
                 S3FS_PRN_ERR("could not flush(%s): result=%d", path, result);
             }
             StatCache::getStatCacheData()->DelStat(path);
         }
+    }
 
     int mask = (O_RDONLY != (fi->flags & O_ACCMODE) ? W_OK : R_OK);
     if(0 != (result = check_parent_object_access(path, X_OK))){
@@ -2390,6 +2412,7 @@ static int s3fs_flush(const char* _path, struct fuse_file_info* fi)
         ent->UpdateMtime(true);         // clear the flag not to update mtime.
         ent->UpdateCtime();
         result = ent->Flush(false);
+        StatCache::getStatCacheData()->DelStat(path);
     }
     S3FS_MALLOCTRIM(0);
 
@@ -3048,6 +3071,9 @@ static int s3fs_setxattr(const char* path, const char* name, const char* value,
             // then the meta is pending and accumulated to be put after the upload is complete.
             S3FS_PRN_INFO("meta pending until upload is complete");
             need_put_header = false;
+
+            // If there is data in the Stats cache, update the Stats cache.
+            StatCache::getStatCacheData()->UpdateMetaStats(strpath, updatemeta);
         }
     }
     if(need_put_header){
@@ -3318,6 +3344,9 @@ static int s3fs_removexattr(const char* path, const char* name)
             // then the meta is pending and accumulated to be put after the upload is complete.
             S3FS_PRN_INFO("meta pending until upload is complete");
             need_put_header = false;
+
+            // If there is data in the Stats cache, update the Stats cache.
+            StatCache::getStatCacheData()->UpdateMetaStats(strpath, updatemeta);
         }
     }
     if(need_put_header){