Merge branch 'jc/lockfile'

* jc/lockfile:
  ref-log: style fixes.
  refs.c: convert it to use lockfile interface.
  Make index file locking code reusable to others.

14 files changed, 127 insertions, 120 deletions

diff --git a/Makefile b/Makefile
index f802043aa9..265a716704 100644
--- a/Makefile
+++ b/Makefile
@@ -210,7 +210,7 @@ DIFF_OBJS = \
 
 LIB_OBJS = \
 	blob.o commit.o connect.o csum-file.o cache-tree.o base85.o \
-	date.o diff-delta.o entry.o exec_cmd.o ident.o index.o \
+	date.o diff-delta.o entry.o exec_cmd.o ident.o lockfile.o \
 	object.o pack-check.o patch-delta.o path.o pkt-line.o \
 	quote.o read-cache.o refs.o run-command.o dir.o \
 	server-info.o setup.o sha1_file.o sha1_name.o strbuf.o \
diff --git a/builtin-add.c b/builtin-add.c
index 02fe38b0c4..bfbbb1bf52 100644
--- a/builtin-add.c
+++ b/builtin-add.c
@@ -122,7 +122,7 @@ static int add_file_to_index(const char *path, int verbose)
 	return 0;
 }
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 int cmd_add(int argc, const char **argv, char **envp)
 {
@@ -134,9 +134,9 @@ int cmd_add(int argc, const char **argv, char **envp)
 
 	git_config(git_default_config);
 
-	newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	newfd = hold_lock_file_for_update(&lock_file, get_index_file());
 	if (newfd < 0)
-		die("unable to create new cachefile");
+		die("unable to create new index file");
 
 	if (read_cache() < 0)
 		die("index file corrupt");
@@ -181,7 +181,7 @@ int cmd_add(int argc, const char **argv, char **envp)
 
 	if (active_cache_changed) {
 		if (write_cache(newfd, active_cache, active_nr) ||
-		    commit_index_file(&cache_file))
+		    commit_lock_file(&lock_file))
 			die("Unable to write new index file");
 	}
 
diff --git a/builtin-apply.c b/builtin-apply.c
index 6a4fb9663d..e113c74dd8 100644
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -2072,7 +2072,7 @@ static void write_out_results(struct patch *list, int skipped_patch)
 	}
 }
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 static struct excludes {
 	struct excludes *next;
@@ -2133,8 +2133,12 @@ static int apply_patch(int fd, const char *filename)
 		apply = 0;
 
 	write_index = check_index && apply;
-	if (write_index && newfd < 0)
-		newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	if (write_index && newfd < 0) {
+		newfd = hold_lock_file_for_update(&lock_file,
+						  get_index_file());
+		if (newfd < 0)
+			die("unable to create new index file");
+	}
 	if (check_index) {
 		if (read_cache() < 0)
 			die("unable to read index file");
@@ -2312,8 +2316,8 @@ int cmd_apply(int argc, const char **argv, char **envp)
 
 	if (write_index) {
 		if (write_cache(newfd, active_cache, active_nr) ||
-		    commit_index_file(&cache_file))
-			die("Unable to write new cachefile");
+		    commit_lock_file(&lock_file))
+			die("Unable to write new index file");
 	}
 
 	return 0;
diff --git a/builtin-read-tree.c b/builtin-read-tree.c
index 8d1a22d373..bb50fbd274 100644
--- a/builtin-read-tree.c
+++ b/builtin-read-tree.c
@@ -853,7 +853,7 @@ static void prime_cache_tree(void)
 
 static const char read_tree_usage[] = "git-read-tree (<sha> | -m [--aggressive] [-u | -i] <sha1> [<sha2> [<sha3>]])";
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 int cmd_read_tree(int argc, const char **argv, char **envp)
 {
@@ -864,9 +864,9 @@ int cmd_read_tree(int argc, const char **argv, char **envp)
 	setup_git_directory();
 	git_config(git_default_config);
 
-	newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	newfd = hold_lock_file_for_update(&lock_file, get_index_file());
 	if (newfd < 0)
-		die("unable to create new cachefile");
+		die("unable to create new index file");
 
 	git_config(git_default_config);
 
@@ -981,7 +981,7 @@ int cmd_read_tree(int argc, const char **argv, char **envp)
 	}
 
 	if (write_cache(newfd, active_cache, active_nr) ||
-	    commit_index_file(&cache_file))
+	    commit_lock_file(&lock_file))
 		die("unable to write new index file");
 	return 0;
 }
diff --git a/builtin-rm.c b/builtin-rm.c
index e7793a20f5..ef2f8b5d09 100644
--- a/builtin-rm.c
+++ b/builtin-rm.c
@@ -41,7 +41,7 @@ static int remove_file(const char *name)
 	return ret;
 }
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 int cmd_rm(int argc, const char **argv, char **envp)
 {
@@ -53,7 +53,7 @@ int cmd_rm(int argc, const char **argv, char **envp)
 
 	git_config(git_default_config);
 
-	newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	newfd = hold_lock_file_for_update(&lock_file, get_index_file());
 	if (newfd < 0)
 		die("unable to create new index file");
 
@@ -144,7 +144,7 @@ int cmd_rm(int argc, const char **argv, char **envp)
 
 	if (active_cache_changed) {
 		if (write_cache(newfd, active_cache, active_nr) ||
-		    commit_index_file(&cache_file))
+		    commit_lock_file(&lock_file))
 			die("Unable to write new index file");
 	}
 
diff --git a/cache.h b/cache.h
index d530af97cc..d5d7fe4f8c 100644
--- a/cache.h
+++ b/cache.h
@@ -167,13 +167,13 @@ extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 #define REFRESH_IGNORE_MISSING	0x0008	/* ignore non-existent */
 extern int refresh_cache(unsigned int flags);
 
-struct cache_file {
-	struct cache_file *next;
-	char lockfile[PATH_MAX];
+struct lock_file {
+	struct lock_file *next;
+	char filename[PATH_MAX];
 };
-extern int hold_index_file_for_update(struct cache_file *, const char *path);
-extern int commit_index_file(struct cache_file *);
-extern void rollback_index_file(struct cache_file *);
+extern int hold_lock_file_for_update(struct lock_file *, const char *path);
+extern int commit_lock_file(struct lock_file *);
+extern void rollback_lock_file(struct lock_file *);
 
 /* Environment bits from configuration mechanism */
 extern int trust_executable_bit;
diff --git a/checkout-index.c b/checkout-index.c
index 9876af6fd6..ea40bc29be 100644
--- a/checkout-index.c
+++ b/checkout-index.c
@@ -168,7 +168,7 @@ static int checkout_all(void)
 static const char checkout_cache_usage[] =
 "git-checkout-index [-u] [-q] [-a] [-f] [-n] [--stage=[123]|all] [--prefix=<string>] [--temp] [--] <file>...";
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 int main(int argc, char **argv)
 {
@@ -211,9 +211,8 @@ int main(int argc, char **argv)
 		if (!strcmp(arg, "-u") || !strcmp(arg, "--index")) {
 			state.refresh_cache = 1;
 			if (newfd < 0)
-				newfd = hold_index_file_for_update
-					(&cache_file,
-					 get_index_file());
+				newfd = hold_lock_file_for_update
+					(&lock_file, get_index_file());
 			if (newfd < 0)
 				die("cannot open index.lock file.");
 			continue;
@@ -262,7 +261,7 @@ int main(int argc, char **argv)
 		 */
 		if (state.refresh_cache) {
 			close(newfd); newfd = -1;
-			rollback_index_file(&cache_file);
+			rollback_lock_file(&lock_file);
 		}
 		state.refresh_cache = 0;
 	}
@@ -312,7 +311,7 @@ int main(int argc, char **argv)
 
 	if (0 <= newfd &&
 	    (write_cache(newfd, active_cache, active_nr) ||
-	     commit_index_file(&cache_file)))
-		die("Unable to write new cachefile");
+	     commit_lock_file(&lock_file)))
+		die("Unable to write new index file");
 	return 0;
 }
diff --git a/fetch.c b/fetch.c
index e040ef97b6..cf6c99490c 100644
--- a/fetch.c
+++ b/fetch.c
@@ -150,7 +150,8 @@ static int process(struct object *obj)
 	if (has_sha1_file(obj->sha1)) {
 		/* We already have it, so we should scan it now. */
 		obj->flags |= TO_SCAN;
-	} else {
+	}
+	else {
 		if (obj->flags & COMPLETE)
 			return 0;
 		prefetch(obj->sha1);
@@ -255,7 +256,8 @@ int pull(char *target)
 		if (write_ref_log_details) {
 			msg = xmalloc(strlen(write_ref_log_details) + 12);
 			sprintf(msg, "fetch from %s", write_ref_log_details);
-		} else
+		}
+		else
 			msg = NULL;
 		ret = write_ref_sha1(lock, sha1, msg ? msg : "fetch (unknown)");
 		if (msg)
diff --git a/index.c b/index.c
deleted file mode 100644
index f92b960ae4..0000000000
--- a/index.c
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright (c) 2005, Junio C Hamano
- */
-#include <signal.h>
-#include "cache.h"
-
-static struct cache_file *cache_file_list;
-
-static void remove_lock_file(void)
-{
-	while (cache_file_list) {
-		if (cache_file_list->lockfile[0])
-			unlink(cache_file_list->lockfile);
-		cache_file_list = cache_file_list->next;
-	}
-}
-
-static void remove_lock_file_on_signal(int signo)
-{
-	remove_lock_file();
-	signal(SIGINT, SIG_DFL);
-	raise(signo);
-}
-
-int hold_index_file_for_update(struct cache_file *cf, const char *path)
-{
-	int fd;
-	sprintf(cf->lockfile, "%s.lock", path);
-	fd = open(cf->lockfile, O_RDWR | O_CREAT | O_EXCL, 0666);
-	if (fd >=0 && !cf->next) {
-		cf->next = cache_file_list;
-		cache_file_list = cf;
-		signal(SIGINT, remove_lock_file_on_signal);
-		atexit(remove_lock_file);
-	}
-	return fd;
-}
-
-int commit_index_file(struct cache_file *cf)
-{
-	char indexfile[PATH_MAX];
-	int i;
-	strcpy(indexfile, cf->lockfile);
-	i = strlen(indexfile) - 5; /* .lock */
-	indexfile[i] = 0;
-	i = rename(cf->lockfile, indexfile);
-	cf->lockfile[0] = 0;
-	return i;
-}
-
-void rollback_index_file(struct cache_file *cf)
-{
-	if (cf->lockfile[0])
-		unlink(cf->lockfile);
-	cf->lockfile[0] = 0;
-}
-
diff --git a/lockfile.c b/lockfile.c
new file mode 100644
index 0000000000..9bc60837aa
--- /dev/null
+++ b/lockfile.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2005, Junio C Hamano
+ */
+#include <signal.h>
+#include "cache.h"
+
+static struct lock_file *lock_file_list;
+
+static void remove_lock_file(void)
+{
+	while (lock_file_list) {
+		if (lock_file_list->filename[0])
+			unlink(lock_file_list->filename);
+		lock_file_list = lock_file_list->next;
+	}
+}
+
+static void remove_lock_file_on_signal(int signo)
+{
+	remove_lock_file();
+	signal(SIGINT, SIG_DFL);
+	raise(signo);
+}
+
+int hold_lock_file_for_update(struct lock_file *lk, const char *path)
+{
+	int fd;
+	sprintf(lk->filename, "%s.lock", path);
+	fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
+	if (fd >=0 && !lk->next) {
+		lk->next = lock_file_list;
+		lock_file_list = lk;
+		signal(SIGINT, remove_lock_file_on_signal);
+		atexit(remove_lock_file);
+	}
+	return fd;
+}
+
+int commit_lock_file(struct lock_file *lk)
+{
+	char result_file[PATH_MAX];
+	int i;
+	strcpy(result_file, lk->filename);
+	i = strlen(result_file) - 5; /* .lock */
+	result_file[i] = 0;
+	i = rename(lk->filename, result_file);
+	lk->filename[0] = 0;
+	return i;
+}
+
+void rollback_lock_file(struct lock_file *lk)
+{
+	if (lk->filename[0])
+		unlink(lk->filename);
+	lk->filename[0] = 0;
+}
+
diff --git a/refs.c b/refs.c
index eeb1196ec4..f91b7716dc 100644
--- a/refs.c
+++ b/refs.c
@@ -259,7 +259,7 @@ int check_ref_format(const char *ref)
 	}
 }
 
-static struct ref_lock* verify_lock(struct ref_lock *lock,
+static struct ref_lock *verify_lock(struct ref_lock *lock,
 	const unsigned char *old_sha1, int mustexist)
 {
 	char buf[40];
@@ -285,7 +285,7 @@ static struct ref_lock* verify_lock(struct ref_lock *lock,
 	return lock;
 }
 
-static struct ref_lock* lock_ref_sha1_basic(const char *path,
+static struct ref_lock *lock_ref_sha1_basic(const char *path,
 	int plen,
 	const unsigned char *old_sha1, int mustexist)
 {
@@ -301,19 +301,18 @@ static struct ref_lock* lock_ref_sha1_basic(const char *path,
 		unlock_ref(lock);
 		return NULL;
 	}
+	lock->lk = xcalloc(1, sizeof(struct lock_file));
 
 	lock->ref_file = strdup(path);
-	lock->lock_file = strdup(mkpath("%s.lock", lock->ref_file));
 	lock->log_file = strdup(git_path("logs/%s", lock->ref_file + plen));
 	lock->force_write = lstat(lock->ref_file, &st) && errno == ENOENT;
 
-	if (safe_create_leading_directories(lock->lock_file))
-		die("unable to create directory for %s", lock->lock_file);
-	lock->lock_fd = open(lock->lock_file,
-		O_WRONLY | O_CREAT | O_EXCL, 0666);
+	if (safe_create_leading_directories(lock->ref_file))
+		die("unable to create directory for %s", lock->ref_file);
+	lock->lock_fd = hold_lock_file_for_update(lock->lk, lock->ref_file);
 	if (lock->lock_fd < 0) {
 		error("Couldn't open lock file %s: %s",
-			lock->lock_file, strerror(errno));
+		      lock->lk->filename, strerror(errno));
 		unlock_ref(lock);
 		return NULL;
 	}
@@ -321,7 +320,7 @@ static struct ref_lock* lock_ref_sha1_basic(const char *path,
 	return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
 }
 
-struct ref_lock* lock_ref_sha1(const char *ref,
+struct ref_lock *lock_ref_sha1(const char *ref,
 	const unsigned char *old_sha1, int mustexist)
 {
 	if (check_ref_format(ref))
@@ -330,23 +329,23 @@ struct ref_lock* lock_ref_sha1(const char *ref,
 		5 + strlen(ref), old_sha1, mustexist);
 }
 
-struct ref_lock* lock_any_ref_for_update(const char *ref,
+struct ref_lock *lock_any_ref_for_update(const char *ref,
 	const unsigned char *old_sha1, int mustexist)
 {
 	return lock_ref_sha1_basic(git_path("%s", ref),
 		strlen(ref), old_sha1, mustexist);
 }
 
-void unlock_ref (struct ref_lock *lock)
+void unlock_ref(struct ref_lock *lock)
 {
 	if (lock->lock_fd >= 0) {
 		close(lock->lock_fd);
-		unlink(lock->lock_file);
+		/* Do not free lock->lk -- atexit() still looks at them */
+		if (lock->lk)
+			rollback_lock_file(lock->lk);
 	}
 	if (lock->ref_file)
 		free(lock->ref_file);
-	if (lock->lock_file)
-		free(lock->lock_file);
 	if (lock->log_file)
 		free(lock->log_file);
 	free(lock);
@@ -385,7 +384,8 @@ static int log_ref_write(struct ref_lock *lock,
 			sha1_to_hex(sha1),
 			comitter,
 			msg);
-	} else {
+	}
+	else {
 		maxlen = strlen(comitter) + 2*40 + 4;
 		logrec = xmalloc(maxlen);
 		len = snprintf(logrec, maxlen, "%s %s %s\n",
@@ -415,7 +415,7 @@ int write_ref_sha1(struct ref_lock *lock,
 	if (write(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
 	    write(lock->lock_fd, &term, 1) != 1
 		|| close(lock->lock_fd) < 0) {
-		error("Couldn't write %s", lock->lock_file);
+		error("Couldn't write %s", lock->lk->filename);
 		unlock_ref(lock);
 		return -1;
 	}
@@ -423,7 +423,7 @@ int write_ref_sha1(struct ref_lock *lock,
 		unlock_ref(lock);
 		return -1;
 	}
-	if (rename(lock->lock_file, lock->ref_file) < 0) {
+	if (commit_lock_file(lock->lk)) {
 		error("Couldn't set %s", lock->ref_file);
 		unlock_ref(lock);
 		return -1;
@@ -478,10 +478,12 @@ int read_ref_at(const char *ref, unsigned long at_time, unsigned char *sha1)
 						"warning: Log %s has gap after %s.\n",
 						logfile, show_rfc2822_date(date, tz));
 				}
-			} else if (date == at_time) {
+			}
+			else if (date == at_time) {
 				if (get_sha1_hex(rec + 41, sha1))
 					die("Log %s is corrupt.", logfile);
-			} else {
+			}
+			else {
 				if (get_sha1_hex(rec + 41, logged_sha1))
 					die("Log %s is corrupt.", logfile);
 				if (memcmp(logged_sha1, sha1, 20)) {
diff --git a/refs.h b/refs.h
index 6c946eabcf..553155c04a 100644
--- a/refs.h
+++ b/refs.h
@@ -3,8 +3,8 @@
 
 struct ref_lock {
 	char *ref_file;
-	char *lock_file;
 	char *log_file;
+	struct lock_file *lk;
 	unsigned char old_sha1[20];
 	int lock_fd;
 	int force_write;
@@ -24,13 +24,13 @@ extern int for_each_remote_ref(int (*fn)(const char *path, const unsigned char *
 extern int get_ref_sha1(const char *ref, unsigned char *sha1);
 
 /** Locks a "refs/" ref returning the lock on success and NULL on failure. **/
-extern struct ref_lock* lock_ref_sha1(const char *ref, const unsigned char *old_sha1, int mustexist);
+extern struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1, int mustexist);
 
 /** Locks any ref (for 'HEAD' type refs). */
-extern struct ref_lock* lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int mustexist);
+extern struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int mustexist);
 
 /** Release any lock taken but not written. **/
-extern void unlock_ref (struct ref_lock *lock);
+extern void unlock_ref(struct ref_lock *lock);
 
 /** Writes sha1 into the ref specified by the lock. **/
 extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg);
diff --git a/update-index.c b/update-index.c
index 956b6b34f9..fbccc4a67b 100644
--- a/update-index.c
+++ b/update-index.c
@@ -186,7 +186,7 @@ static void chmod_path(int flip, const char *path)
 	die("git-update-index: cannot chmod %cx '%s'", flip, path);
 }
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 static void update_one(const char *path, const char *prefix, int prefix_length)
 {
@@ -489,9 +489,9 @@ int main(int argc, const char **argv)
 
 	git_config(git_default_config);
 
-	newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	newfd = hold_lock_file_for_update(&lock_file, get_index_file());
 	if (newfd < 0)
-		die("unable to create new cachefile");
+		die("unable to create new index file");
 
 	entries = read_cache();
 	if (entries < 0)
@@ -645,8 +645,8 @@ int main(int argc, const char **argv)
  finish:
 	if (active_cache_changed) {
 		if (write_cache(newfd, active_cache, active_nr) ||
-		    commit_index_file(&cache_file))
-			die("Unable to write new cachefile");
+		    commit_lock_file(&lock_file))
+			die("Unable to write new index file");
 	}
 
 	return has_errors ? 1 : 0;
diff --git a/write-tree.c b/write-tree.c
index 7a4f691d8a..d6a605893d 100644
--- a/write-tree.c
+++ b/write-tree.c
@@ -11,7 +11,7 @@ static int missing_ok = 0;
 
 static const char write_tree_usage[] = "git-write-tree [--missing-ok]";
 
-static struct cache_file cache_file;
+static struct lock_file lock_file;
 
 int main(int argc, char **argv)
 {
@@ -19,7 +19,7 @@ int main(int argc, char **argv)
 
 	setup_git_directory();
 
-	newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	newfd = hold_lock_file_for_update(&lock_file, get_index_file());
 	entries = read_cache();
 	if (argc == 2) {
 		if (!strcmp(argv[1], "--missing-ok"))
@@ -45,7 +45,7 @@ int main(int argc, char **argv)
 			die("git-write-tree: error building trees");
 		if (0 <= newfd) {
 			if (!write_cache(newfd, active_cache, active_nr))
-				commit_index_file(&cache_file);
+				commit_lock_file(&lock_file);
 		}
 		/* Not being able to write is fine -- we are only interested
 		 * in updating the cache-tree part, and if the next caller