Added fake_diskfree option to deceive free disk space for test

src/fdcache.cpp

@@ -82,6 +82,7 @@ bool            FdManager::is_lock_init(false);
 std::string     FdManager::cache_dir;
 bool            FdManager::check_cache_dir_exist(false);
 off_t           FdManager::free_disk_space = 0;
+off_t           FdManager::fake_used_disk_space = 0;
 std::string     FdManager::check_cache_output;
 bool            FdManager::checked_lseek(false);
 bool            FdManager::have_lseek_hole(false);
@@ -254,6 +255,20 @@ off_t FdManager::SetEnsureFreeDiskSpace(off_t size)
     return old;
 }
 
+bool FdManager::InitFakeUsedDiskSize(off_t fake_freesize)
+{
+    FdManager::fake_used_disk_space = 0;    // At first, clear this value because this value is used in GetFreeDiskSpace.
+
+    off_t actual_freesize = FdManager::GetFreeDiskSpace(NULL);
+
+    if(fake_freesize < actual_freesize){
+        FdManager::fake_used_disk_space = actual_freesize - fake_freesize;
+    }else{
+        FdManager::fake_used_disk_space = 0;
+    }
+    return true;
+}
+
 off_t FdManager::GetFreeDiskSpace(const char* path)
 {
     struct statvfs vfsbuf;
@@ -276,7 +291,10 @@ off_t FdManager::GetFreeDiskSpace(const char* path)
         S3FS_PRN_ERR("could not get vfs stat by errno(%d)", errno);
         return 0;
     }
-    return (vfsbuf.f_bavail * vfsbuf.f_frsize);
+
+    off_t actual_freesize = vfsbuf.f_bavail * vfsbuf.f_frsize;
+
+    return (FdManager::fake_used_disk_space < actual_freesize ? (actual_freesize - FdManager::fake_used_disk_space) : 0);
 }
 
 bool FdManager::IsSafeDiskSpace(const char* path, off_t size)

src/fdcache.h

@@ -36,7 +36,8 @@ class FdManager
       static bool            is_lock_init;
       static std::string     cache_dir;
       static bool            check_cache_dir_exist;
-      static off_t           free_disk_space; // limit free disk space
+      static off_t           free_disk_space;       // limit free disk space
+      static off_t           fake_used_disk_space;  // difference between fake free disk space and actual at startup(for test/debug)
       static std::string     check_cache_output;
       static bool            checked_lseek;
       static bool            have_lseek_hole;
@@ -72,6 +73,7 @@ class FdManager
       static bool HasOpenEntityFd(const char* path);
       static off_t GetEnsureFreeDiskSpace();
       static off_t SetEnsureFreeDiskSpace(off_t size);
+      static bool InitFakeUsedDiskSize(off_t fake_freesize);
       static bool IsSafeDiskSpace(const char* path, off_t size);
       static void FreeReservedDiskSpace(off_t size);
       static bool ReserveDiskSpace(off_t size);

src/s3fs.cpp

@@ -98,6 +98,7 @@ static bool support_compat_dir    = true;// default supports compatibility direc
 static int max_keys_list_object   = 1000;// default is 1000
 static off_t max_dirty_data       = 5LL * 1024LL * 1024LL * 1024LL;
 static bool use_wtf8              = false;
+static off_t fake_diskfree_size   = -1; // default is not set(-1)
 
 static const std::string allbucket_fields_type;              // special key for mapping(This name is absolutely not used as a bucket name)
 static const std::string keyval_fields_type    = "\t";       // special key for mapping(This name is absolutely not used as a bucket name)
@@ -4620,6 +4621,13 @@ static int my_fuse_opt_proc(void* data, const char* arg, int key, struct fuse_ar
             FdManager::SetEnsureFreeDiskSpace(dfsize);
             return 0;
         }
+        if(is_prefix(arg, "fake_diskfree=")){
+            S3FS_PRN_WARN("The fake_diskfree option was specified. Use this option for testing or debugging.");
+
+            // [NOTE] This value is used for initializing to FdManager after parsing all options.
+            fake_diskfree_size = cvt_strtoofft(strchr(arg, '=') + sizeof(char), /*base=*/ 10) * 1024 * 1024;
+            return 0;
+        }
         if(is_prefix(arg, "multipart_threshold=")){
             multipart_threshold = static_cast<int64_t>(cvt_strtoofft(strchr(arg, '=') + sizeof(char), /*base=*/ 10)) * 1024 * 1024;
             if(multipart_threshold <= MIN_MULTIPART_SIZE){
@@ -5128,6 +5136,11 @@ int main(int argc, char* argv[])
         exit(EXIT_FAILURE);
     }
 
+    // set fake free disk space
+    if(-1 != fake_diskfree_size){
+        FdManager::InitFakeUsedDiskSize(fake_diskfree_size);
+    }
+
     // check IBM IAM requirements
     if(is_ibm_iam_auth){
         // check that default ACL is either public-read or private

test/small-integration-test.sh

@@ -38,25 +38,14 @@ mkdir "${CACHE_DIR}"
 
 #reserve 200MB for data cache
 source test-utils.sh
-CACHE_DISK_AVAIL_SIZE=`get_disk_avail_size $CACHE_DIR`
-if [ `uname` = "Darwin" ]; then
-    # [FIXME]
-    # Only on MacOS, there are cases where process or system
-    # other than the s3fs cache uses disk space.
-    # We can imagine that this is caused by Timemachine, but
-    # there is no workaround, so s3fs cache size is set +1gb
-    # for error bypass.
-    #
-    ENSURE_DISKFREE_SIZE=$((CACHE_DISK_AVAIL_SIZE - 1200))
-else
-    ENSURE_DISKFREE_SIZE=$((CACHE_DISK_AVAIL_SIZE - 200))
-fi
+FAKE_FREE_DISK_SIZE=200
+ENSURE_DISKFREE_SIZE=10
 
 export CACHE_DIR
 export ENSURE_DISKFREE_SIZE 
 if [ -n "${ALL_TESTS}" ]; then
     FLAGS=(
-        "use_cache=${CACHE_DIR} -o ensure_diskfree=${ENSURE_DISKFREE_SIZE}"
+        "use_cache=${CACHE_DIR} -o ensure_diskfree=${ENSURE_DISKFREE_SIZE} -o fake_diskfree=${FAKE_FREE_DISK_SIZE}"
         enable_content_md5
         enable_noobj_cache
         max_stat_cache_size=100