Merge branch 'rj/cygwin-clarify-use-of-cheating-lstat'

Cygwin port added a "not quite correct but a lot faster and good
enough for many lstat() calls that are only used to see if the
working tree entity matches the index entry" lstat() emulation some
time ago, and it started biting us in places.  This removes it and
uses the standard lstat() that comes with Cygwin.

Recent topic that uses lstat on packed-refs file is broken when
this cheating lstat is used, and this is a simplest fix that is
also the cleanest direction to go in the long run.

* rj/cygwin-clarify-use-of-cheating-lstat:
  cygwin: Remove the Win32 l/stat() implementation

9 files changed, 2 insertions, 200 deletions

diff --git a/Documentation/config.txt b/Documentation/config.txt
index e0b923f428..ec57a15ac5 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -213,17 +213,6 @@ The default is true, except linkgit:git-clone[1] or linkgit:git-init[1]
 will probe and set core.fileMode false if appropriate when the
 repository is created.
 
-core.ignoreCygwinFSTricks::
-	This option is only used by Cygwin implementation of Git. If false,
-	the Cygwin stat() and lstat() functions are used. This may be useful
-	if your repository consists of a few separate directories joined in
-	one hierarchy using Cygwin mount. If true, Git uses native Win32 API
-	whenever it is possible and falls back to Cygwin functions only to
-	handle symbol links. The native mode is more than twice faster than
-	normal Cygwin l/stat() functions. True by default, unless core.filemode
-	is true, in which case ignoreCygwinFSTricks is ignored as Cygwin's
-	POSIX emulation is required to support core.filemode.
-
 core.ignorecase::
 	If true, this option enables various workarounds to enable
 	Git to work better on filesystems that are not case sensitive,
diff --git a/Makefile b/Makefile
index ef442ebad0..3588ca1b6a 100644
--- a/Makefile
+++ b/Makefile
@@ -654,7 +654,6 @@ LIB_H += color.h
 LIB_H += column.h
 LIB_H += commit.h
 LIB_H += compat/bswap.h
-LIB_H += compat/cygwin.h
 LIB_H += compat/mingw.h
 LIB_H += compat/obstack.h
 LIB_H += compat/poll/poll.h
diff --git a/compat/cygwin.c b/compat/cygwin.c
deleted file mode 100644
index 91ce5d4c7a..0000000000
--- a/compat/cygwin.c
+++ /dev/null
@@ -1,157 +0,0 @@
-#define CYGWIN_C
-#define WIN32_LEAN_AND_MEAN
-#include <sys/stat.h>
-#include <sys/errno.h>
-#include "win32.h"
-#include "../git-compat-util.h"
-#include "../cache.h" /* to read configuration */
-
-/*
- * Return POSIX permission bits, regardless of core.ignorecygwinfstricks
- */
-int cygwin_get_st_mode_bits(const char *path, int *mode)
-{
-	struct stat st;
-	if (lstat(path, &st) < 0)
-		return -1;
-	*mode = st.st_mode;
-	return 0;
-}
-
-static inline void filetime_to_timespec(const FILETIME *ft, struct timespec *ts)
-{
-	long long winTime = ((long long)ft->dwHighDateTime << 32) +
-			ft->dwLowDateTime;
-	winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
-	/* convert 100-nsecond interval to seconds and nanoseconds */
-	ts->tv_sec = (time_t)(winTime/10000000);
-	ts->tv_nsec = (long)(winTime - ts->tv_sec*10000000LL) * 100;
-}
-
-#define size_to_blocks(s) (((s)+511)/512)
-
-/* do_stat is a common implementation for cygwin_lstat and cygwin_stat.
- *
- * To simplify its logic, in the case of cygwin symlinks, this implementation
- * falls back to the cygwin version of stat/lstat, which is provided as the
- * last argument.
- */
-static int do_stat(const char *file_name, struct stat *buf, stat_fn_t cygstat)
-{
-	WIN32_FILE_ATTRIBUTE_DATA fdata;
-
-	if (file_name[0] == '/')
-		return cygstat (file_name, buf);
-
-	if (!(errno = get_file_attr(file_name, &fdata))) {
-		/*
-		 * If the system attribute is set and it is not a directory then
-		 * it could be a symbol link created in the nowinsymlinks mode.
-		 * Normally, Cygwin works in the winsymlinks mode, so this situation
-		 * is very unlikely. For the sake of simplicity of our code, let's
-		 * Cygwin to handle it.
-		 */
-		if ((fdata.dwFileAttributes & FILE_ATTRIBUTE_SYSTEM) &&
-		    !(fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
-			return cygstat(file_name, buf);
-
-		/* fill out the stat structure */
-		buf->st_dev = buf->st_rdev = 0; /* not used by Git */
-		buf->st_ino = 0;
-		buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
-		buf->st_nlink = 1;
-		buf->st_uid = buf->st_gid = 0;
-#ifdef __CYGWIN_USE_BIG_TYPES__
-		buf->st_size = ((_off64_t)fdata.nFileSizeHigh << 32) +
-			fdata.nFileSizeLow;
-#else
-		buf->st_size = (off_t)fdata.nFileSizeLow;
-#endif
-		buf->st_blocks = size_to_blocks(buf->st_size);
-		filetime_to_timespec(&fdata.ftLastAccessTime, &buf->st_atim);
-		filetime_to_timespec(&fdata.ftLastWriteTime, &buf->st_mtim);
-		filetime_to_timespec(&fdata.ftCreationTime, &buf->st_ctim);
-		return 0;
-	} else if (errno == ENOENT) {
-		/*
-		 * In the winsymlinks mode (which is the default), Cygwin
-		 * emulates symbol links using Windows shortcut files. These
-		 * files are formed by adding .lnk extension. So, if we have
-		 * not found the specified file name, it could be that it is
-		 * a symbol link. Let's Cygwin to deal with that.
-		 */
-		return cygstat(file_name, buf);
-	}
-	return -1;
-}
-
-/* We provide our own lstat/stat functions, since the provided Cygwin versions
- * of these functions are too slow. These stat functions are tailored for Git's
- * usage, and therefore they are not meant to be complete and correct emulation
- * of lstat/stat functionality.
- */
-static int cygwin_lstat(const char *path, struct stat *buf)
-{
-	return do_stat(path, buf, lstat);
-}
-
-static int cygwin_stat(const char *path, struct stat *buf)
-{
-	return do_stat(path, buf, stat);
-}
-
-
-/*
- * At start up, we are trying to determine whether Win32 API or cygwin stat
- * functions should be used. The choice is determined by core.ignorecygwinfstricks.
- * Reading this option is not always possible immediately as git_dir may
- * not be set yet. So until it is set, use cygwin lstat/stat functions.
- * However, if core.filemode is set, we must use the Cygwin posix
- * stat/lstat as the Windows stat functions do not determine posix filemode.
- *
- * Note that git_cygwin_config() does NOT call git_default_config() and this
- * is deliberate.  Many commands read from config to establish initial
- * values in variables and later tweak them from elsewhere (e.g. command line).
- * init_stat() is called lazily on demand, typically much late in the program,
- * and calling git_default_config() from here would break such variables.
- */
-static int native_stat = 1;
-static int core_filemode = 1; /* matches trust_executable_bit default */
-
-static int git_cygwin_config(const char *var, const char *value, void *cb)
-{
-	if (!strcmp(var, "core.ignorecygwinfstricks"))
-		native_stat = git_config_bool(var, value);
-	else if (!strcmp(var, "core.filemode"))
-		core_filemode = git_config_bool(var, value);
-	return 0;
-}
-
-static int init_stat(void)
-{
-	if (have_git_dir() && git_config(git_cygwin_config,NULL)) {
-		if (!core_filemode && native_stat) {
-			cygwin_stat_fn = cygwin_stat;
-			cygwin_lstat_fn = cygwin_lstat;
-		} else {
-			cygwin_stat_fn = stat;
-			cygwin_lstat_fn = lstat;
-		}
-		return 0;
-	}
-	return 1;
-}
-
-static int cygwin_stat_stub(const char *file_name, struct stat *buf)
-{
-	return (init_stat() ? stat : *cygwin_stat_fn)(file_name, buf);
-}
-
-static int cygwin_lstat_stub(const char *file_name, struct stat *buf)
-{
-	return (init_stat() ? lstat : *cygwin_lstat_fn)(file_name, buf);
-}
-
-stat_fn_t cygwin_stat_fn = cygwin_stat_stub;
-stat_fn_t cygwin_lstat_fn = cygwin_lstat_stub;
-
diff --git a/compat/cygwin.h b/compat/cygwin.h
deleted file mode 100644
index c04965a2e0..0000000000
--- a/compat/cygwin.h
+++ /dev/null
@@ -1,14 +0,0 @@
-#include <sys/types.h>
-#include <sys/stat.h>
-
-typedef int (*stat_fn_t)(const char*, struct stat*);
-extern stat_fn_t cygwin_stat_fn;
-extern stat_fn_t cygwin_lstat_fn;
-int cygwin_get_st_mode_bits(const char *path, int *mode);
-
-#define get_st_mode_bits(p,m) cygwin_get_st_mode_bits((p),(m))
-#ifndef CYGWIN_C
-/* cygwin.c needs the original lstat() */
-#define stat(path, buf) (*cygwin_stat_fn)(path, buf)
-#define lstat(path, buf) (*cygwin_lstat_fn)(path, buf)
-#endif
diff --git a/config.mak.uname b/config.mak.uname
index b45b910759..b27f51d486 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -171,7 +171,6 @@ ifeq ($(uname_O),Cygwin)
 	NO_FAST_WORKING_DIRECTORY = UnfortunatelyYes
 	NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease
 	X = .exe
-	COMPAT_OBJS += compat/cygwin.o
 	UNRELIABLE_FSTAT = UnfortunatelyYes
 	SPARSE_FLAGS = -isystem /usr/include/w32api -Wno-one-bit-signed-bitfield
 endif
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 32d1b45c7e..5da920ecd9 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -1958,7 +1958,6 @@ _git_config ()
 		core.fileMode
 		core.fsyncobjectfiles
 		core.gitProxy
-		core.ignoreCygwinFSTricks
 		core.ignoreStat
 		core.ignorecase
 		core.logAllRefUpdates
diff --git a/git-compat-util.h b/git-compat-util.h
index cc4ba4d18f..115cb1da42 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -129,8 +129,6 @@
 #include <poll.h>
 #endif
 
-extern int get_st_mode_bits(const char *path, int *mode);
-
 #if defined(__MINGW32__)
 /* pull in Windows compatibility stuff */
 #include "compat/mingw.h"
@@ -171,7 +169,6 @@ typedef unsigned long uintptr_t;
 #undef _XOPEN_SOURCE
 #include <grp.h>
 #define _XOPEN_SOURCE 600
-#include "compat/cygwin.h"
 #else
 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 #include <grp.h>
diff --git a/help.c b/help.c
index 08c54ef1c1..f068925bb7 100644
--- a/help.c
+++ b/help.c
@@ -107,10 +107,7 @@ static int is_executable(const char *name)
 	    !S_ISREG(st.st_mode))
 		return 0;
 
-#if defined(GIT_WINDOWS_NATIVE) || defined(__CYGWIN__)
-#if defined(__CYGWIN__)
-if ((st.st_mode & S_IXUSR) == 0)
-#endif
+#if defined(GIT_WINDOWS_NATIVE)
 {	/* cannot trust the executable bit, peek into the file instead */
 	char buf[3] = { 0 };
 	int n;
diff --git a/path.c b/path.c
index 7f3324aeea..3d244d3e03 100644
--- a/path.c
+++ b/path.c
@@ -5,13 +5,7 @@
 #include "strbuf.h"
 #include "string-list.h"
 
-#ifndef get_st_mode_bits
-/*
- * The replacement lstat(2) we use on Cygwin is incomplete and
- * may return wrong permission bits. Most of the time we do not care,
- * but the callsites of this wrapper do care.
- */
-int get_st_mode_bits(const char *path, int *mode)
+static int get_st_mode_bits(const char *path, int *mode)
 {
 	struct stat st;
 	if (lstat(path, &st) < 0)
@@ -19,7 +13,6 @@ int get_st_mode_bits(const char *path, int *mode)
 	*mode = st.st_mode;
 	return 0;
 }
-#endif
 
 static char bad_path[] = "/bad-path/";