Merge branch 'jc/reftable-core-fsync'

The write codepath for the reftable data learned to honor
core.fsync configuration.

* jc/reftable-core-fsync:
  reftable/stack: fsync "tables.list" during compaction
  reftable: honor core.fsync

9 files changed, 54 insertions, 19 deletions

diff --git a/reftable/merged_test.c b/reftable/merged_test.c
index 46908f738f..bf090b474e 100644
--- a/reftable/merged_test.c
+++ b/reftable/merged_test.c
@@ -42,7 +42,7 @@ static void write_test_table(struct strbuf *buf,
 		}
 	}
 
-	w = reftable_new_writer(&strbuf_add_void, buf, &opts);
+	w = reftable_new_writer(&strbuf_add_void, &noop_flush, buf, &opts);
 	reftable_writer_set_limits(w, min, max);
 
 	for (i = 0; i < n; i++) {
@@ -70,7 +70,7 @@ static void write_test_log_table(struct strbuf *buf,
 		.exact_log_message = 1,
 	};
 	struct reftable_writer *w = NULL;
-	w = reftable_new_writer(&strbuf_add_void, buf, &opts);
+	w = reftable_new_writer(&strbuf_add_void, &noop_flush, buf, &opts);
 	reftable_writer_set_limits(w, update_index, update_index);
 
 	for (i = 0; i < n; i++) {
@@ -412,7 +412,7 @@ static void test_default_write_opts(void)
 	struct reftable_write_options opts = { 0 };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 
 	struct reftable_ref_record rec = {
 		.refname = "master",
diff --git a/reftable/readwrite_test.c b/reftable/readwrite_test.c
index b8a3224016..6b99daeaf2 100644
--- a/reftable/readwrite_test.c
+++ b/reftable/readwrite_test.c
@@ -51,7 +51,7 @@ static void write_table(char ***names, struct strbuf *buf, int N,
 		.hash_id = hash_id,
 	};
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, buf, &opts);
 	struct reftable_ref_record ref = { NULL };
 	int i = 0, n;
 	struct reftable_log_record log = { NULL };
@@ -130,7 +130,7 @@ static void test_log_buffer_size(void)
 					   .message = "commit: 9\n",
 				   } } };
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 
 	/* This tests buffer extension for log compression. Must use a random
 	   hash, to ensure that the compressed part is larger than the original.
@@ -171,7 +171,7 @@ static void test_log_overflow(void)
 					   .message = msg,
 				   } } };
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 
 	uint8_t hash1[GIT_SHA1_RAWSZ]  = {1}, hash2[GIT_SHA1_RAWSZ] = { 2 };
 
@@ -202,7 +202,7 @@ static void test_log_write_read(void)
 	struct reftable_block_source source = { NULL };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	const struct reftable_stats *stats = NULL;
 	reftable_writer_set_limits(w, 0, N);
 	for (i = 0; i < N; i++) {
@@ -294,7 +294,7 @@ static void test_log_zlib_corruption(void)
 	struct reftable_block_source source = { 0 };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	const struct reftable_stats *stats = NULL;
 	uint8_t hash1[GIT_SHA1_RAWSZ] = { 1 };
 	uint8_t hash2[GIT_SHA1_RAWSZ] = { 2 };
@@ -535,7 +535,7 @@ static void test_table_refs_for(int indexed)
 
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 
 	struct reftable_iterator it = { NULL };
 	int j;
@@ -628,7 +628,7 @@ static void test_write_empty_table(void)
 	struct reftable_write_options opts = { 0 };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	struct reftable_block_source source = { NULL };
 	struct reftable_reader *rd = NULL;
 	struct reftable_ref_record rec = { NULL };
@@ -666,7 +666,7 @@ static void test_write_object_id_min_length(void)
 	};
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	struct reftable_ref_record ref = {
 		.update_index = 1,
 		.value_type = REFTABLE_REF_VAL1,
@@ -701,7 +701,7 @@ static void test_write_object_id_length(void)
 	};
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	struct reftable_ref_record ref = {
 		.update_index = 1,
 		.value_type = REFTABLE_REF_VAL1,
@@ -735,7 +735,7 @@ static void test_write_empty_key(void)
 	struct reftable_write_options opts = { 0 };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	struct reftable_ref_record ref = {
 		.refname = "",
 		.update_index = 1,
@@ -758,7 +758,7 @@ static void test_write_key_order(void)
 	struct reftable_write_options opts = { 0 };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	struct reftable_ref_record refs[2] = {
 		{
 			.refname = "b",
@@ -801,7 +801,7 @@ static void test_write_multiple_indices(void)
 	struct reftable_reader *reader;
 	int err, i;
 
-	writer = reftable_new_writer(&strbuf_add_void, &writer_buf, &opts);
+	writer = reftable_new_writer(&strbuf_add_void, &noop_flush, &writer_buf, &opts);
 	reftable_writer_set_limits(writer, 1, 1);
 	for (i = 0; i < 100; i++) {
 		struct reftable_ref_record ref = {
diff --git a/reftable/refname_test.c b/reftable/refname_test.c
index 699e1aea41..b9cc62554e 100644
--- a/reftable/refname_test.c
+++ b/reftable/refname_test.c
@@ -30,7 +30,7 @@ static void test_conflict(void)
 	struct reftable_write_options opts = { 0 };
 	struct strbuf buf = STRBUF_INIT;
 	struct reftable_writer *w =
-		reftable_new_writer(&strbuf_add_void, &buf, &opts);
+		reftable_new_writer(&strbuf_add_void, &noop_flush, &buf, &opts);
 	struct reftable_ref_record rec = {
 		.refname = "a/b",
 		.value_type = REFTABLE_REF_SYMREF,
diff --git a/reftable/reftable-writer.h b/reftable/reftable-writer.h
index db8de197f6..7c7cae5f99 100644
--- a/reftable/reftable-writer.h
+++ b/reftable/reftable-writer.h
@@ -88,6 +88,7 @@ struct reftable_stats {
 /* reftable_new_writer creates a new writer */
 struct reftable_writer *
 reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t),
+		    int (*flush_func)(void *),
 		    void *writer_arg, struct reftable_write_options *opts);
 
 /* Set the range of update indices for the records we will add. When writing a
diff --git a/reftable/stack.c b/reftable/stack.c
index bf3869ce70..bed25240e3 100644
--- a/reftable/stack.c
+++ b/reftable/stack.c
@@ -8,6 +8,7 @@ https://developers.google.com/open-source/licenses/bsd
 
 #include "stack.h"
 
+#include "../write-or-die.h"
 #include "system.h"
 #include "merged.h"
 #include "reader.h"
@@ -16,7 +17,6 @@ https://developers.google.com/open-source/licenses/bsd
 #include "reftable-record.h"
 #include "reftable-merged.h"
 #include "writer.h"
-
 #include "tempfile.h"
 
 static int stack_try_add(struct reftable_stack *st,
@@ -47,6 +47,13 @@ static ssize_t reftable_fd_write(void *arg, const void *data, size_t sz)
 	return write_in_full(*fdp, data, sz);
 }
 
+static int reftable_fd_flush(void *arg)
+{
+	int *fdp = (int *)arg;
+
+	return fsync_component(FSYNC_COMPONENT_REFERENCE, *fdp);
+}
+
 int reftable_new_stack(struct reftable_stack **dest, const char *dir,
 		       struct reftable_write_options config)
 {
@@ -653,6 +660,9 @@ int reftable_addition_commit(struct reftable_addition *add)
 		goto done;
 	}
 
+	fsync_component_or_die(FSYNC_COMPONENT_REFERENCE, lock_file_fd,
+			       get_tempfile_path(add->lock_file));
+
 	err = rename_tempfile(&add->lock_file, add->stack->list_file);
 	if (err < 0) {
 		err = REFTABLE_IO_ERROR;
@@ -747,7 +757,7 @@ int reftable_addition_add(struct reftable_addition *add,
 			goto done;
 		}
 	}
-	wr = reftable_new_writer(reftable_fd_write, &tab_fd,
+	wr = reftable_new_writer(reftable_fd_write, reftable_fd_flush, &tab_fd,
 				 &add->stack->config);
 	err = write_table(wr, arg);
 	if (err < 0)
@@ -839,7 +849,7 @@ static int stack_compact_locked(struct reftable_stack *st, int first, int last,
 	strbuf_addstr(temp_tab, ".temp.XXXXXX");
 
 	tab_fd = mkstemp(temp_tab->buf);
-	wr = reftable_new_writer(reftable_fd_write, &tab_fd, &st->config);
+	wr = reftable_new_writer(reftable_fd_write, reftable_fd_flush, &tab_fd, &st->config);
 
 	err = stack_write_compact(st, wr, first, last, config);
 	if (err < 0)
@@ -1116,6 +1126,14 @@ static int stack_compact_range(struct reftable_stack *st, int first, int last,
 		unlink(new_table_path.buf);
 		goto done;
 	}
+
+	err = fsync_component(FSYNC_COMPONENT_REFERENCE, lock_file_fd);
+	if (err < 0) {
+		err = REFTABLE_IO_ERROR;
+		unlink(new_table_path.buf);
+		goto done;
+	}
+
 	err = close(lock_file_fd);
 	lock_file_fd = -1;
 	if (err < 0) {
diff --git a/reftable/test_framework.c b/reftable/test_framework.c
index 04044fc1a0..4066924eee 100644
--- a/reftable/test_framework.c
+++ b/reftable/test_framework.c
@@ -20,3 +20,8 @@ ssize_t strbuf_add_void(void *b, const void *data, size_t sz)
 	strbuf_add(b, data, sz);
 	return sz;
 }
+
+int noop_flush(void *arg)
+{
+	return 0;
+}
diff --git a/reftable/test_framework.h b/reftable/test_framework.h
index ee44f735ae..687390f9c2 100644
--- a/reftable/test_framework.h
+++ b/reftable/test_framework.h
@@ -56,4 +56,6 @@ void set_test_hash(uint8_t *p, int i);
  */
 ssize_t strbuf_add_void(void *b, const void *data, size_t sz);
 
+int noop_flush(void *);
+
 #endif
diff --git a/reftable/writer.c b/reftable/writer.c
index ee4590e20f..92935baa70 100644
--- a/reftable/writer.c
+++ b/reftable/writer.c
@@ -121,6 +121,7 @@ static struct strbuf reftable_empty_strbuf = STRBUF_INIT;
 
 struct reftable_writer *
 reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t),
+		    int (*flush_func)(void *),
 		    void *writer_arg, struct reftable_write_options *opts)
 {
 	struct reftable_writer *wp =
@@ -136,6 +137,7 @@ reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t),
 	wp->write = writer_func;
 	wp->write_arg = writer_arg;
 	wp->opts = *opts;
+	wp->flush = flush_func;
 	writer_reinit_block_writer(wp, BLOCK_TYPE_REF);
 
 	return wp;
@@ -603,6 +605,12 @@ int reftable_writer_close(struct reftable_writer *w)
 	put_be32(p, crc32(0, footer, p - footer));
 	p += 4;
 
+	err = w->flush(w->write_arg);
+	if (err < 0) {
+		err = REFTABLE_IO_ERROR;
+		goto done;
+	}
+
 	err = padded_write(w, footer, footer_size(writer_version(w)), 0);
 	if (err < 0)
 		goto done;
diff --git a/reftable/writer.h b/reftable/writer.h
index 09b88673d9..8d0df9cc52 100644
--- a/reftable/writer.h
+++ b/reftable/writer.h
@@ -16,6 +16,7 @@ https://developers.google.com/open-source/licenses/bsd
 
 struct reftable_writer {
 	ssize_t (*write)(void *, const void *, size_t);
+	int (*flush)(void *);
 	void *write_arg;
 	int pending_padding;
 	struct strbuf last_key;