Merge 'build-in git-mktree'

* commit '633e3556ccbc': (5835 commits)
  build-in git-mktree
  allow -t abbreviation for --track in git branch
  gitweb: Remove function prototypes (cleanup)
  Documentation: cloning to empty directory is allowed
  Clarify kind of conflict in merge-one-file helper
  git config: clarify --add and --get-color
  archive-tar.c: squelch a type mismatch warning
  Start 1.6.4 development
  Start 1.6.3.1 maintenance series.
  GIT 1.6.3
  t4029: use sh instead of bash
  t4200: convert sed expression which operates on non-text file to perl
  t4200: remove two unnecessary lines
  t/annotate-tests.sh: avoid passing a non-newline terminated file to sed
  t4118: avoid sed invocation on file without terminating newline
  t4118: add missing '&&'
  t8005: use egrep when extended regular expressions are required
  git-clean doc: the command only affects paths under $(cwd)
  improve error message in config.c
  t4018-diff-funcname: add cpp xfuncname pattern to syntax test
  ...

1 files changed, 88 insertions, 23 deletions

diff --git a/lockfile.c b/lockfile.c
index 9a1f64d8d7..828d19f452 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -2,6 +2,7 @@
  * Copyright (c) 2005, Junio C Hamano
  */
 #include "cache.h"
+#include "sigchain.h"
 
 static struct lock_file *lock_file_list;
 static const char *alternate_index_output;
@@ -12,8 +13,11 @@ static void remove_lock_file(void)
 
 	while (lock_file_list) {
 		if (lock_file_list->owner == me &&
-		    lock_file_list->filename[0])
+		    lock_file_list->filename[0]) {
+			if (lock_file_list->fd >= 0)
+				close(lock_file_list->fd);
 			unlink(lock_file_list->filename);
+		}
 		lock_file_list = lock_file_list->next;
 	}
 }
@@ -21,7 +25,7 @@ static void remove_lock_file(void)
 static void remove_lock_file_on_signal(int signo)
 {
 	remove_lock_file();
-	signal(SIGINT, SIG_DFL);
+	sigchain_pop(signo);
 	raise(signo);
 }
 
@@ -92,7 +96,7 @@ static char *resolve_symlink(char *p, size_t s)
 			return p;
 		}
 
-		if (link[0] == '/') {
+		if (is_absolute_path(link)) {
 			/* absolute path simply replaces p */
 			if (link_len < s)
 				strcpy(p, link);
@@ -105,7 +109,7 @@ static char *resolve_symlink(char *p, size_t s)
 			 * link is a relative path, so I must replace the
 			 * last element of p with it.
 			 */
-			char *r = (char*)last_path_elm(p);
+			char *r = (char *)last_path_elm(p);
 			if (r - p + link_len < s)
 				strcpy(r, link);
 			else {
@@ -118,22 +122,22 @@ static char *resolve_symlink(char *p, size_t s)
 }
 
 
-static int lock_file(struct lock_file *lk, const char *path)
+static int lock_file(struct lock_file *lk, const char *path, int flags)
 {
-	int fd;
-
-	if (strlen(path) >= sizeof(lk->filename)) return -1;
+	if (strlen(path) >= sizeof(lk->filename))
+		return -1;
 	strcpy(lk->filename, path);
 	/*
 	 * subtract 5 from size to make sure there's room for adding
 	 * ".lock" for the lock file name
 	 */
-	resolve_symlink(lk->filename, sizeof(lk->filename)-5);
+	if (!(flags & LOCK_NODEREF))
+		resolve_symlink(lk->filename, sizeof(lk->filename)-5);
 	strcat(lk->filename, ".lock");
-	fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
-	if (0 <= fd) {
+	lk->fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
+	if (0 <= lk->fd) {
 		if (!lock_file_list) {
-			signal(SIGINT, remove_lock_file_on_signal);
+			sigchain_push_common(remove_lock_file_on_signal);
 			atexit(remove_lock_file);
 		}
 		lk->owner = getpid();
@@ -148,32 +152,87 @@ static int lock_file(struct lock_file *lk, const char *path)
 	}
 	else
 		lk->filename[0] = 0;
+	return lk->fd;
+}
+
+
+NORETURN void unable_to_lock_index_die(const char *path, int err)
+{
+	if (err == EEXIST) {
+		die("Unable to create '%s.lock': %s.\n\n"
+		    "If no other git process is currently running, this probably means a\n"
+		    "git process crashed in this repository earlier. Make sure no other git\n"
+		    "process is running and remove the file manually to continue.",
+		    path, strerror(err));
+	} else {
+		die("Unable to create '%s.lock': %s", path, strerror(err));
+	}
+}
+
+int hold_lock_file_for_update(struct lock_file *lk, const char *path, int flags)
+{
+	int fd = lock_file(lk, path, flags);
+	if (fd < 0 && (flags & LOCK_DIE_ON_ERROR))
+		unable_to_lock_index_die(path, errno);
 	return fd;
 }
 
-int hold_lock_file_for_update(struct lock_file *lk, const char *path, int die_on_error)
+int hold_lock_file_for_append(struct lock_file *lk, const char *path, int flags)
 {
-	int fd = lock_file(lk, path);
-	if (fd < 0 && die_on_error)
-		die("unable to create '%s.lock': %s", path, strerror(errno));
+	int fd, orig_fd;
+
+	fd = lock_file(lk, path, flags);
+	if (fd < 0) {
+		if (flags & LOCK_DIE_ON_ERROR)
+			unable_to_lock_index_die(path, errno);
+		return fd;
+	}
+
+	orig_fd = open(path, O_RDONLY);
+	if (orig_fd < 0) {
+		if (errno != ENOENT) {
+			if (flags & LOCK_DIE_ON_ERROR)
+				die("cannot open '%s' for copying", path);
+			close(fd);
+			return error("cannot open '%s' for copying", path);
+		}
+	} else if (copy_fd(orig_fd, fd)) {
+		if (flags & LOCK_DIE_ON_ERROR)
+			exit(128);
+		close(fd);
+		return -1;
+	}
 	return fd;
 }
 
+int close_lock_file(struct lock_file *lk)
+{
+	int fd = lk->fd;
+	lk->fd = -1;
+	return close(fd);
+}
+
 int commit_lock_file(struct lock_file *lk)
 {
 	char result_file[PATH_MAX];
-	int i;
+	size_t i;
+	if (lk->fd >= 0 && close_lock_file(lk))
+		return -1;
 	strcpy(result_file, lk->filename);
 	i = strlen(result_file) - 5; /* .lock */
 	result_file[i] = 0;
-	i = rename(lk->filename, result_file);
+	if (rename(lk->filename, result_file))
+		return -1;
 	lk->filename[0] = 0;
-	return i;
+	return 0;
 }
 
 int hold_locked_index(struct lock_file *lk, int die_on_error)
 {
-	return hold_lock_file_for_update(lk, get_index_file(), die_on_error);
+	return hold_lock_file_for_update(lk, get_index_file(),
+					 die_on_error
+					 ? LOCK_DIE_ON_ERROR
+					 : 0);
 }
 
 void set_alternate_index_output(const char *name)
@@ -184,9 +243,12 @@ void set_alternate_index_output(const char *name)
 int commit_locked_index(struct lock_file *lk)
 {
 	if (alternate_index_output) {
-		int result = rename(lk->filename, alternate_index_output);
+		if (lk->fd >= 0 && close_lock_file(lk))
+			return -1;
+		if (rename(lk->filename, alternate_index_output))
+			return -1;
 		lk->filename[0] = 0;
-		return result;
+		return 0;
 	}
 	else
 		return commit_lock_file(lk);
@@ -194,7 +256,10 @@ int commit_locked_index(struct lock_file *lk)
 
 void rollback_lock_file(struct lock_file *lk)
 {
-	if (lk->filename[0])
+	if (lk->filename[0]) {
+		if (lk->fd >= 0)
+			close(lk->fd);
 		unlink(lk->filename);
+	}
 	lk->filename[0] = 0;
 }