[RFC] Add "write-index" hook

@@ -3,6 +3,7 @@
  */
 #include <signal.h>
 #include "cache.h"
+#include "run-command.h"
 
 static struct cache_file *cache_file_list;
 

@@ -20,9 +21,15 @@ static void remove_lock_file_on_signal(i
 	remove_lock_file();
 }
 
+static char write_index_hook[] = "hooks/write-index";
+
 int hold_index_file_for_update(struct cache_file *cf, const char *path)
 {
 	int fd;
+
+	if (run_hook(write_index_hook))
+		return error("hook declined to write index\n");
+
 	sprintf(cf->lockfile, "%s.lock", path);
 	fd = open(cf->lockfile, O_RDWR | O_CREAT | O_EXCL, 0666);
 	if (fd >=0 && !cf->next) {

@@ -59,36 +59,6 @@ static int verify_old_ref(const char *na
 
 static char update_hook[] = "hooks/update";
 
-static int run_update_hook(const char *refname,
-			   char *old_hex, char *new_hex)
-{
-	int code;
-
-	if (access(update_hook, X_OK) < 0)
-		return 0;
-	code = run_command(update_hook, refname, old_hex, new_hex, NULL);
-	switch (code) {
-	case 0:
-		return 0;
-	case -ERR_RUN_COMMAND_FORK:
-		die("hook fork failed");
-	case -ERR_RUN_COMMAND_EXEC:
-		die("hook execute failed");
-	case -ERR_RUN_COMMAND_WAITPID:
-		die("waitpid failed");
-	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
-		die("waitpid is confused");
-	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
-		fprintf(stderr, "%s died of signal", update_hook);
-		return -1;
-	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
-		die("%s died strangely", update_hook);
-	default:
-		error("%s exited with error code %d", update_hook, -code);
-		return -code;
-	}
-}
-
 static int update(const char *name,
 		  unsigned char *old_sha1, unsigned char *new_sha1)
 {

@@ -133,7 +103,7 @@ static int update(const char *name,
 		unlink(lock_name);
 		return error("%s changed during push", name);
 	}
-	if (run_update_hook(name, old_hex, new_hex)) {
+	if (run_hook(update_hook, name, old_hex, new_hex)) {
 		unlink(lock_name);
 		return error("hook declined to update %s\n", name);
 	}

@@ -149,33 +119,6 @@ static int update(const char *name,
 
 static char update_post_hook[] = "hooks/post-update";
 
-static void run_update_post_hook(struct command *cmd)
-{
-	struct command *cmd_p;
-	int argc;
-	char **argv;
-
-	if (access(update_post_hook, X_OK) < 0)
-		return;
-	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
-		if (!cmd_p->updated)
-			continue;
-		argc++;
-	}
-	argv = xmalloc(sizeof(*argv) * (1 + argc));
-	argv[0] = update_post_hook;
-
-	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
-		if (!cmd_p->updated)
-			continue;
-		argv[argc] = xmalloc(strlen(cmd_p->ref_name) + 1);
-		strcpy(argv[argc], cmd_p->ref_name);
-		argc++;
-	}
-	argv[argc] = NULL;
-	run_command_v_opt(argc, argv, RUN_COMMAND_NO_STDIO);
-}
-
 /*
  * This gets called after(if) we've successfully
  * unpacked the data payload.

@@ -189,7 +132,7 @@ static void execute_commands(void)
 				       cmd->old_sha1, cmd->new_sha1);
 		cmd = cmd->next;
 	}
-	run_update_post_hook(commands);
+	run_hook(update_post_hook, commands);
 }
 
 static void read_head_info(void)

@@ -67,3 +67,52 @@ int run_command(const char *cmd, ...)
 		return error("too many args to run %s", cmd);
 	return run_command_v_opt(argc, argv, 0);
 }
+
+int run_hook(const char* hook, ...)
+{
+	int argc;
+	char *argv[MAX_RUN_COMMAND_ARGS];
+	const char *arg;
+	va_list param;
+	int code;
+
+	if (access(hook, X_OK) < 0)
+		return 0;
+
+	va_start(param, hook);
+	argv[0] = (char*) hook;
+	argc = 1;
+	while (argc < MAX_RUN_COMMAND_ARGS) {
+		arg = argv[argc++] = va_arg(param, char *);
+		if (!arg)
+			break;
+	}
+	va_end(param);
+	if (MAX_RUN_COMMAND_ARGS <= argc)
+		return error("too many args to run %s", hook);
+
+	code = run_command_v_opt(argc, argv, 0);
+
+	switch (code) {
+	case 0:
+		return 0;
+	case -ERR_RUN_COMMAND_FORK:
+		die("hook fork failed");
+	case -ERR_RUN_COMMAND_EXEC:
+		die("hook execute failed");
+	case -ERR_RUN_COMMAND_WAITPID:
+		die("waitpid failed");
+	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
+		die("waitpid is confused");
+	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
+		fprintf(stderr, "%s died of signal", hook);
+		return -1;
+	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
+		die("%s died strangely", hook);
+	default:
+		error("%s exited with error code %d", hook, -code);
+		return -code;
+	}
+}
+
+

@@ -16,5 +16,7 @@ enum {
 int run_command_v_opt(int argc, char **argv, int opt);
 int run_command_v(int argc, char **argv);
 int run_command(const char *cmd, ...);
+/* unlike run_command(), run_hook die()s on errors */
+int run_hook(const char *hook, ...);
 
 #endif