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.

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 \

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");
 	}
 

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;

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;
 }

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");
 	}
 

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;

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;
 }

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)

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;
+}
+