Re: [PATCH 4/4] cygwin: Use native Win32 API for stat

Dmitry Potapov, Sat, Sep 27, 2008 10:43:49 +0200:

Despite all efforts to make the fast implementation as robust as possible,
it may not work well for some very rare situations. I am aware only one
situation: use Cygwin mount to bind unrelated paths inside repository
together.  Therefore, the core.cygwinnativestat configuration option is
provided, which controls whether native or Cygwin version of stat is used.

cygwin.tryWindowsState? (I think cygwin has to get its own section)

+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);

formatting: space after function name.

+
+		/* 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;
+}

I like it and will be keeping in my tree. Thanks!