Merge remote-tracking branch 'kblees/kb/fscache-v4-tentative-1.8.5' into thicket-1.8.5.2

Author: nalla

Documentation/config.txt

@@ -706,6 +706,12 @@ relatively high IO latencies.  When enabled, Git will do the
 index comparison to the filesystem data in parallel, allowing
 overlapping IO's.  Defaults to true.
 
+core.fscache::
+	Enable additional caching of file system data for some operations.
++
+Git for Windows uses this to bulk-read and cache lstat data of entire
+directories (instead of doing lstat file by file).
+
 core.createObject::
 	You can set this to 'link', in which case a hardlink followed by
 	a delete of the source are used to make sure that object creation

builtin/commit.c

@@ -1360,6 +1360,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 		       PATHSPEC_PREFER_FULL,
 		       prefix, argv);
 
+	enable_fscache(1);
 	read_cache_preload(&s.pathspec);
 	refresh_index(&the_index, REFRESH_QUIET|REFRESH_UNMERGED, &s.pathspec, NULL, NULL);
 

cache.h

@@ -627,6 +627,8 @@ enum hide_dotfiles_type {
 };
 extern enum hide_dotfiles_type hide_dotfiles;
 
+extern int core_fscache;
+
 enum branch_track {
 	BRANCH_TRACK_UNSPECIFIED = -1,
 	BRANCH_TRACK_NEVER = 0,

compat/mingw.c

@@ -476,22 +476,6 @@ int mingw_chmod(const char *filename, int mode)
 	return _wchmod(wfilename, mode);
 }
 
-/*
- * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
- * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
- */
-static inline long long filetime_to_hnsec(const FILETIME *ft)
-{
-	long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
-	/* Windows to Unix Epoch conversion */
-	return winTime - 116444736000000000LL;
-}
-
-static inline time_t filetime_to_time_t(const FILETIME *ft)
-{
-	return (time_t)(filetime_to_hnsec(ft) / 10000000);
-}
-
 /* We keep the do_lstat code in a separate function to avoid recursion.
  * When a path ends with a slash, the stat will fail with ENOENT. In
  * this case, we strip the trailing slashes and stat again.
@@ -592,6 +576,8 @@ static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 	return do_lstat(follow, alt_name, buf);
 }
 
+int (*lstat)(const char *file_name, struct stat *buf) = mingw_lstat;
+
 int mingw_lstat(const char *file_name, struct stat *buf)
 {
 	return do_stat_internal(0, file_name, buf);

compat/mingw.h

@@ -297,6 +297,22 @@ static inline int getrlimit(int resource, struct rlimit *rlp)
 	return 0;
 }
 
+/*
+ * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
+ * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
+ */
+static inline long long filetime_to_hnsec(const FILETIME *ft)
+{
+	long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
+	/* Windows to Unix Epoch conversion */
+	return winTime - 116444736000000000LL;
+}
+
+static inline time_t filetime_to_time_t(const FILETIME *ft)
+{
+	return (time_t)(filetime_to_hnsec(ft) / 10000000);
+}
+
 /*
  * Use mingw specific stat()/lstat()/fstat() implementations on Windows.
  */
@@ -320,7 +336,7 @@ int mingw_fstat(int fd, struct stat *buf);
 #ifdef lstat
 #undef lstat
 #endif
-#define lstat mingw_lstat
+extern int (*lstat)(const char *file_name, struct stat *buf);
 
 #ifndef _stati64
 # define _stati64(x,y) mingw_stat(x,y)

compat/win32/dirent.c

@@ -1,15 +1,19 @@
 #include "../../git-compat-util.h"
 
-struct DIR {
+typedef struct dirent_DIR {
+	struct DIR base_dir;  /* extend base struct DIR */
 	struct dirent dd_dir; /* includes d_type */
 	HANDLE dd_handle;     /* FindFirstFile handle */
 	int dd_stat;          /* 0-based index */
-};
+	char dd_name[MAX_PATH * 3]; /* file name (* 3 for UTF-8 conversion) */
+} dirent_DIR;
+
+DIR *(*opendir)(const char *dirname) = dirent_opendir;
 
 static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
 {
-	/* convert UTF-16 name to UTF-8 */
-	xwcstoutf(ent->d_name, fdata->cFileName, sizeof(ent->d_name));
+	/* convert UTF-16 name to UTF-8 (d_name points to dirent_DIR.dd_name) */
+	xwcstoutf(ent->d_name, fdata->cFileName, MAX_PATH * 3);
 
 	/* Set file type, based on WIN32_FIND_DATA */
 	if (fdata->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
@@ -18,41 +22,7 @@ static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
 		ent->d_type = DT_REG;
 }
 
-DIR *opendir(const char *name)
-{
-	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
-	WIN32_FIND_DATAW fdata;
-	HANDLE h;
-	int len;
-	DIR *dir;
-
-	/* convert name to UTF-16 and check length < MAX_PATH */
-	if ((len = xutftowcs_path(pattern, name)) < 0)
-		return NULL;
-
-	/* append optional '/' and wildcard '*' */
-	if (len && !is_dir_sep(pattern[len - 1]))
-		pattern[len++] = '/';
-	pattern[len++] = '*';
-	pattern[len] = 0;
-
-	/* open find handle */
-	h = FindFirstFileW(pattern, &fdata);
-	if (h == INVALID_HANDLE_VALUE) {
-		DWORD err = GetLastError();
-		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
-		return NULL;
-	}
-
-	/* initialize DIR structure and copy first dir entry */
-	dir = xmalloc(sizeof(DIR));
-	dir->dd_handle = h;
-	dir->dd_stat = 0;
-	finddata2dirent(&dir->dd_dir, &fdata);
-	return dir;
-}
-
-struct dirent *readdir(DIR *dir)
+static struct dirent *dirent_readdir(dirent_DIR *dir)
 {
 	if (!dir) {
 		errno = EBADF; /* No set_errno for mingw */
@@ -79,7 +49,7 @@ struct dirent *readdir(DIR *dir)
 	return &dir->dd_dir;
 }
 
-int closedir(DIR *dir)
+static int dirent_closedir(dirent_DIR *dir)
 {
 	if (!dir) {
 		errno = EBADF;
@@ -90,3 +60,40 @@ int closedir(DIR *dir)
 	free(dir);
 	return 0;
 }
+
+DIR *dirent_opendir(const char *name)
+{
+	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
+	WIN32_FIND_DATAW fdata;
+	HANDLE h;
+	int len;
+	dirent_DIR *dir;
+
+	/* convert name to UTF-16 and check length < MAX_PATH */
+	if ((len = xutftowcs_path(pattern, name)) < 0)
+		return NULL;
+
+	/* append optional '/' and wildcard '*' */
+	if (len && !is_dir_sep(pattern[len - 1]))
+		pattern[len++] = '/';
+	pattern[len++] = '*';
+	pattern[len] = 0;
+
+	/* open find handle */
+	h = FindFirstFileW(pattern, &fdata);
+	if (h == INVALID_HANDLE_VALUE) {
+		DWORD err = GetLastError();
+		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
+		return NULL;
+	}
+
+	/* initialize DIR structure and copy first dir entry */
+	dir = xmalloc(sizeof(dirent_DIR));
+	dir->base_dir.preaddir = (struct dirent *(*)(DIR *dir)) dirent_readdir;
+	dir->base_dir.pclosedir = (int (*)(DIR *dir)) dirent_closedir;
+	dir->dd_dir.d_name = dir->dd_name;
+	dir->dd_handle = h;
+	dir->dd_stat = 0;
+	finddata2dirent(&dir->dd_dir, &fdata);
+	return (DIR*) dir;
+}

compat/win32/dirent.h

@@ -1,20 +1,32 @@
 #ifndef DIRENT_H
 #define DIRENT_H
 
-typedef struct DIR DIR;
-
 #define DT_UNKNOWN 0
 #define DT_DIR     1
 #define DT_REG     2
 #define DT_LNK     3
 
 struct dirent {
-	unsigned char d_type;      /* file type to prevent lstat after readdir */
-	char d_name[MAX_PATH * 3]; /* file name (* 3 for UTF-8 conversion) */
+	unsigned char d_type; /* file type to prevent lstat after readdir */
+	char *d_name;         /* file name */
 };
 
-DIR *opendir(const char *dirname);
-struct dirent *readdir(DIR *dir);
-int closedir(DIR *dir);
+/*
+ * Base DIR structure, contains pointers to readdir/closedir implementations so
+ * that opendir may choose a concrete implementation on a call-by-call basis.
+ */
+typedef struct DIR {
+	struct dirent *(*preaddir)(struct DIR *dir);
+	int (*pclosedir)(struct DIR *dir);
+} DIR;
+
+/* default dirent implementation */
+extern DIR *dirent_opendir(const char *dirname);
+
+/* current dirent implementation */
+extern DIR *(*opendir)(const char *dirname);
+
+#define readdir(dir) (dir->preaddir(dir))
+#define closedir(dir) (dir->pclosedir(dir))
 
 #endif /* DIRENT_H */