Merge branch 'atetubou/fscache_checkout_flush'

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

builtin/checkout.c

@@ -367,6 +367,7 @@ static int checkout_paths(const struct checkout_opts *opts,
 	state.istate = &the_index;
 
 	enable_delayed_checkout(&state);
+	enable_fscache(1);
 	for (pos = 0; pos < active_nr; pos++) {
 		struct cache_entry *ce = active_cache[pos];
 		if (ce->ce_flags & CE_MATCHED) {
@@ -381,6 +382,7 @@ static int checkout_paths(const struct checkout_opts *opts,
 			pos = skip_same_name(ce, pos) - 1;
 		}
 	}
+	enable_fscache(0);
 	errs |= finish_delayed_checkout(&state);
 
 	if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))

compat/win32/fscache.c

@@ -259,7 +259,7 @@ static void fscache_clear(void)
 /*
  * Checks if the cache is enabled for the given path.
  */
-static inline int fscache_enabled(const char *path)
+int fscache_enabled(const char *path)
 {
 	return enabled > 0 && !is_absolute_path(path);
 }
@@ -430,6 +430,18 @@ int fscache_enable(int enable)
 	return result;
 }
 
+/*
+ * Flush cached stats result when fscache is enabled.
+ */
+void fscache_flush(void)
+{
+	if (enabled) {
+		EnterCriticalSection(&mutex);
+		fscache_clear();
+		LeaveCriticalSection(&mutex);
+	}
+}
+
 /*
  * Lstat replacement, uses the cache if enabled, otherwise redirects to
  * mingw_lstat.

compat/win32/fscache.h

@@ -4,6 +4,12 @@
 int fscache_enable(int enable);
 #define enable_fscache(x) fscache_enable(x)
 
+int fscache_enabled(const char *path);
+#define is_fscache_enabled(path) fscache_enabled(path)
+
+void fscache_flush(void);
+#define flush_fscache() fscache_flush()
+
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
 

dir.c

@@ -824,12 +824,55 @@ static int add_excludes(const char *fname, const char *base, int baselen,
 	size_t size = 0;
 	char *buf;
 
-	fd = open(fname, O_RDONLY);
-	if (fd < 0 || fstat(fd, &st) < 0) {
-		if (fd < 0)
-			warn_on_fopen_errors(fname);
-		else
-			close(fd);
+	/*
+	 * A performance optimization for status.
+	 *
+	 * During a status scan, git looks in each directory for a .gitignore
+	 * file before scanning the directory.  Since .gitignore files are not
+	 * that common, we can waste a lot of time looking for files that are
+	 * not there.  Fortunately, the fscache already knows if the directory
+	 * contains a .gitignore file, since it has already read the directory
+	 * and it already has the stat-data.
+	 *
+	 * If the fscache is enabled, use the fscache-lstat() interlude to see
+	 * if the file exists (in the fscache hash maps) before trying to open()
+	 * it.
+	 *
+	 * This causes problem when the .gitignore file is a symlink, because
+	 * we call lstat() rather than stat() on the symlnk and the resulting
+	 * stat-data is for the symlink itself rather than the target file.
+	 * We CANNOT use stat() here because the fscache DOES NOT install an
+	 * interlude for stat() and mingw_stat() always calls "open-fstat-close"
+	 * on the file and defeats the purpose of the optimization here.  Since
+	 * symlinks are even more rare than .gitignore files, we force a fstat()
+	 * after our open() to get stat-data for the target file.
+	 */
+	if (is_fscache_enabled(fname)) {
+		if (lstat(fname, &st) < 0) {
+			fd = -1;
+		} else {
+			fd = open(fname, O_RDONLY);
+			if (fd < 0)
+				warn_on_fopen_errors(fname);
+			else if (S_ISLNK(st.st_mode) && fstat(fd, &st) < 0) {
+				warn_on_fopen_errors(fname);
+				close(fd);
+				fd = -1;
+			}
+		}
+	} else {
+		fd = open(fname, O_RDONLY);
+		if (fd < 0 || fstat(fd, &st) < 0) {
+			if (fd < 0)
+				warn_on_fopen_errors(fname);
+			else {
+				close(fd);
+				fd = -1;
+			}
+		}
+	}
+
+	if (fd < 0) {
 		if (!istate)
 			return -1;
 		r = read_skip_worktree_file_from_index(istate, fname,

entry.c

@@ -367,6 +367,9 @@ static int write_entry(struct cache_entry *ce,
 	}
 
 finish:
+	/* Flush cached lstat in fscache after writing to disk. */
+	flush_fscache();
+
 	if (state->refresh_cache) {
 		assert(state->istate);
 		if (!fstat_done)

fetch-pack.c

@@ -680,6 +680,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 
 	save_commit_buffer = 0;
 
+	enable_fscache(1);
 	for (ref = *refs; ref; ref = ref->next) {
 		struct object *o;
 		unsigned int flags = OBJECT_INFO_QUICK;
@@ -709,6 +710,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 				cutoff = commit->date;
 		}
 	}
+	enable_fscache(0);
 
 	oidset_clear(&loose_oid_set);
 

git-compat-util.h

@@ -1261,6 +1261,14 @@ static inline int is_missing_file_error(int errno_)
 #define enable_fscache(x) /* noop */
 #endif
 
+#ifndef is_fscache_enabled
+#define is_fscache_enabled(path) (0)
+#endif
+
+#ifndef flush_fscache
+#define flush_fscache() /* noop */
+#endif
+
 extern int cmd_main(int, const char **);
 
 /*

t/t7201-co.sh

@@ -32,6 +32,42 @@ fill () {
 }
 
 
+test_expect_success MINGW 'fscache flush cache' '
+
+	git init fscache-test &&
+	cd fscache-test &&
+	git config core.fscache 1 &&
+	echo A > test.txt &&
+	git add test.txt &&
+	git commit -m A &&
+	echo B >> test.txt &&
+	git checkout . &&
+	test -z "$(git status -s)" &&
+	echo A > expect.txt &&
+	test_cmp expect.txt test.txt &&
+	cd .. &&
+	rm -rf fscache-test
+'
+
+test_expect_success MINGW 'fscache flush cache dir' '
+
+	git init fscache-test &&
+	cd fscache-test &&
+	git config core.fscache 1 &&
+	echo A > test.txt &&
+	git add test.txt &&
+	git commit -m A &&
+	rm test.txt &&
+	mkdir test.txt &&
+	touch test.txt/test.txt &&
+	git checkout . &&
+	test -z "$(git status -s)" &&
+	echo A > expect.txt &&
+	test_cmp expect.txt test.txt &&
+	cd .. &&
+	rm -rf fscache-test
+'
+
 test_expect_success setup '
 
 	fill x y z > same &&