[PATCHv2 5/5] refs.c: enable large transactions

[Stefan Beller <sbeller@google.com>]

By closing the file descriptors after creating the lock file we are not
limiting the size of the transaction by the number of available file
descriptors.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 refs.c                | 17 +++++++++++++----
 t/t1400-update-ref.sh |  4 ++--
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/refs.c b/refs.c
index 2013d37..9d01102 100644
--- a/refs.c
+++ b/refs.c
@@ -3055,11 +3055,18 @@ int is_branch(const char *refname)
 static int write_sha1_to_lock_file(struct ref_lock *lock,
 				   const unsigned char *sha1)
 {
-	if (fdopen_lock_file(lock->lk, "w") < 0
-	    || fprintf(lock->lk->fp, "%s\n", sha1_to_hex(sha1)) != 41)
+	if (lock->lk->fd == -1) {
+		if (reopen_lock_file(lock->lk) < 0
+		    || fdopen_lock_file(lock->lk, "w") < 0
+		    || fprintf(lock->lk->fp, "%s\n", sha1_to_hex(sha1)) != 41
+		    || close_lock_file(lock->lk) < 0)
+		    return -1;
+	} else {
+		if (fdopen_lock_file(lock->lk, "w") < 0
+		    || fprintf(lock->lk->fp, "%s\n", sha1_to_hex(sha1)) != 41)
 		return -1;
-	else
-		return 0;
+	}
+	return 0;
 }
 
 /*
@@ -3761,6 +3768,8 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 				    update->refname);
 			goto cleanup;
 		}
+		/* Do not keep all lock files open at the same time. */
+		close_lock_file(update->lock->lk);
 	}
 
 	/* Perform updates first so live commits remain referenced */
diff --git a/t/t1400-update-ref.sh b/t/t1400-update-ref.sh
index 47d2fe9..c593a1d 100755
--- a/t/t1400-update-ref.sh
+++ b/t/t1400-update-ref.sh
@@ -979,7 +979,7 @@ run_with_limited_open_files () {
 
 test_lazy_prereq ULIMIT_FILE_DESCRIPTORS 'run_with_limited_open_files true'
 
-test_expect_failure ULIMIT_FILE_DESCRIPTORS 'large transaction creating branches does not burst open file limit' '
+test_expect_success ULIMIT_FILE_DESCRIPTORS 'large transaction creating branches does not burst open file limit' '
 (
 	for i in $(test_seq 33)
 	do
@@ -990,7 +990,7 @@ test_expect_failure ULIMIT_FILE_DESCRIPTORS 'large transaction creating branches
 )
 '
 
-test_expect_failure ULIMIT_FILE_DESCRIPTORS 'large transaction deleting branches does not burst open file limit' '
+test_expect_success ULIMIT_FILE_DESCRIPTORS 'large transaction deleting branches does not burst open file limit' '
 (
 	for i in $(test_seq 33)
 	do
-- 
2.2.1.62.g3f15098