From b45ea595e6f6b03a749abc2c8e508504429a4cf3 Mon Sep 17 00:00:00 2001 From: Patrick Steinhardt Date: Thu, 2 Apr 2026 09:31:15 +0200 Subject: reftable/stack: provide fsync(3p) via system header Users of the reftable library are expected to provide their own function callback in cases they want to sync(3p) data to disk via the reftable write options. But if no such function was provided we end up calling fsync(3p) directly, which may not even be available on some systems. While dropping the explicit call to fsync(3p) would work, it would lead to an unsafe default behaviour where a project may have forgotten to set up the callback function, and that could lead to potential data loss. So this is not a great solution. Instead, drop the callback function and make it mandatory for the project to define fsync(3p). In the case of Git, we can then easily inject our custom implementation via the "reftable-system.h" header so that we continue to use `fsync_component()`. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano --- reftable/stack.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) (limited to 'reftable/stack.c') diff --git a/reftable/stack.c b/reftable/stack.c index 1c9f21dfe1..fa87b46c37 100644 --- a/reftable/stack.c +++ b/reftable/stack.c @@ -29,13 +29,6 @@ static int stack_filename(struct reftable_buf *dest, struct reftable_stack *st, return 0; } -static int stack_fsync(const struct reftable_write_options *opts, int fd) -{ - if (opts->fsync) - return opts->fsync(fd); - return fsync(fd); -} - static ssize_t reftable_write_data(int fd, const void *data, size_t size) { size_t total_written = 0; @@ -69,7 +62,7 @@ static ssize_t fd_writer_write(void *arg, const void *data, size_t sz) static int fd_writer_flush(void *arg) { struct fd_writer *writer = arg; - return stack_fsync(writer->opts, writer->fd); + return fsync(writer->fd); } static int fd_read_lines(int fd, char ***namesp) @@ -812,7 +805,7 @@ int reftable_addition_commit(struct reftable_addition *add) goto done; } - err = stack_fsync(&add->stack->opts, add->tables_list_lock.fd); + err = fsync(add->tables_list_lock.fd); if (err < 0) { err = REFTABLE_IO_ERROR; goto done; @@ -1480,7 +1473,7 @@ static int stack_compact_range(struct reftable_stack *st, goto done; } - err = stack_fsync(&st->opts, tables_list_lock.fd); + err = fsync(tables_list_lock.fd); if (err < 0) { err = REFTABLE_IO_ERROR; unlink(new_table_path.buf); -- cgit v1.3