reset size to 0 when opening file in 'w' mode

Author: frs69wq

include/fsmod/FileMetadata.hpp

@@ -35,6 +35,7 @@ namespace simgrid::fsmod {
         [[nodiscard]] sg_size_t get_current_size() const { return current_size_; }
         void set_current_size(sg_size_t num_bytes) { current_size_ = num_bytes; }
         [[nodiscard]] sg_size_t get_future_size() const { return future_size_; }
+        void set_future_size(sg_size_t num_bytes) { future_size_ = num_bytes; }
 
         [[nodiscard]] double get_modification_date() const { return modification_date_; }
         void set_modification_date(double date) { modification_date_ = date; }

src/FileSystem.cpp

@@ -164,7 +164,10 @@ namespace simgrid::fsmod {
             metadata = partition->get_file_metadata(dir, file_name);
         } else {
             if (access_mode == "w") {
-                //TODO update metadata to reset size to 0
+                // Opening a file in "w" mode resets its size to 0. Update metadata and partition free space accordingly
+                partition->increase_free_space(metadata->get_current_size());
+                metadata->set_current_size(0);
+                metadata->set_future_size(0);
             }
         }
 

test/jbod_storage_test.cpp

@@ -148,12 +148,14 @@ TEST_F(JBODStorageTest, SingleWrite)  {
         this->setup_platform();
         sg4::Actor::create("TestActor", fs_client_, [this]() {
             std::shared_ptr<sgfs::File> file;
-            XBT_INFO("Create a 10kB file at /dev/a/foo.txt");
+            XBT_INFO("Create a 1MB file at /dev/a/foo.txt");
             ASSERT_NO_THROW(fs_->create_file("/dev/a/foo.txt", "1MB"));
             XBT_INFO("Check remaining space");
             ASSERT_DOUBLE_EQ(fs_->partition_by_name("/dev/a")->get_free_space(), 99 * 1000 *1000);
             XBT_INFO("Open File '/dev/a/foo.txt'");
             ASSERT_NO_THROW(file = fs_->open("/dev/a/foo.txt", "w"));
+            XBT_INFO("Opening file in 'w' mode reset size to 0. Check remaining space");
+            ASSERT_DOUBLE_EQ(fs_->partition_by_name("/dev/a")->get_free_space(), 100 * 1000 *1000);
             XBT_INFO("Write 0B at /dev/a/foo.txt, which should return 0");
             ASSERT_DOUBLE_EQ(file->write(0), 0);
             XBT_INFO("Write 200MB at /dev/a/foo.txt, which should not work");

test/one_disk_storage_test.cpp

@@ -102,17 +102,19 @@ TEST_F(OneDiskStorageTest, SingleWrite)  {
         this->setup_platform();
         sg4::Actor::create("TestActor", host_, [this]() {
             std::shared_ptr<sgfs::File> file;
-            XBT_INFO("Create a 10kB file at /dev/a/foo.txt");
+            XBT_INFO("Create a 1MB file at /dev/a/foo.txt");
             ASSERT_NO_THROW(fs_->create_file("/dev/a/foo.txt", "1MB"));
             XBT_INFO("Check remaining space");
             ASSERT_DOUBLE_EQ(fs_->partition_by_name("/dev/a")->get_free_space(), 99 * 1000 *1000);
             XBT_INFO("Open File '/dev/a/foo.txt'");
             ASSERT_NO_THROW(file = fs_->open("/dev/a/foo.txt", "w"));
+            XBT_INFO("Opening file in 'w' mode reset size to 0. Check remaining space");
+            ASSERT_DOUBLE_EQ(fs_->partition_by_name("/dev/a")->get_free_space(), 100 * 1000 *1000);
             XBT_INFO("Write 0B at /dev/a/foo.txt, which should return 0");
             ASSERT_DOUBLE_EQ(file->write(0), 0);
             XBT_INFO("Write 200MB at /dev/a/foo.txt, which should not work");
             ASSERT_THROW(file->write("200MB"), sgfs::FileSystemException);
-            XBT_INFO("Write 10kB at /dev/a/foo.txt");
+            XBT_INFO("Write 2MB at /dev/a/foo.txt");
             ASSERT_DOUBLE_EQ(file->write("2MB"), 2000000);
             XBT_INFO("Check remaining space");
             ASSERT_DOUBLE_EQ(fs_->partition_by_name("/dev/a")->get_free_space(), 98 * 1000 * 1000);

test/seek_test.cpp

@@ -48,7 +48,11 @@ TEST_F(SeekTest, SeekandTell)  {
             XBT_INFO("Create a 100kB file at /dev/a/foo.txt");
             ASSERT_NO_THROW(this->fs_->create_file("/dev/a/foo.txt", "100kB"));
             XBT_INFO("Open File '/dev/a/foo.txt'");
-            ASSERT_NO_THROW(file = fs_->open("/dev/a/foo.txt", "w"));
+            ASSERT_NO_THROW(file = fs_->open("/dev/a/foo.txt", "a"));
+            XBT_INFO("Check current position, should be 100k ('append' mode)");
+            ASSERT_DOUBLE_EQ(file->tell(), 100*1000);
+            XBT_INFO("Seek back to beginning of file");
+            ASSERT_NO_THROW(file->seek(SEEK_SET));
             XBT_INFO("Check current position, should be 0");
             ASSERT_DOUBLE_EQ(file->tell(), 0);
             XBT_INFO("Seek 1kB forward");