From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 30 Oct 2018 06:43:48 +0000 (+0900)
Subject: Merge branch 'js/mingw-getcwd'
X-Git-Tag: v2.20.0-rc0~102
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/cc6748720f9014b2c2cea8a603acd9ff6a62b87c?hp=d1622fdbdd83831983e8b99250792e5fca7b9159

Merge branch 'js/mingw-getcwd'

The way the Windows port figures out the current directory has been
improved.

* js/mingw-getcwd:
mingw: fix getcwd when the parent directory cannot be queried
mingw: ensure `getcwd()` reports the correct case
---

diff --git a/compat/mingw.c b/compat/mingw.c
index 44264fe3fd..6c3c4ca5a6 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -203,6 +203,31 @@ static int ask_yes_no_if_possible(const char *format, ...)
 	}
 }
 
+/* Normalizes NT paths as returned by some low-level APIs. */
+static wchar_t *normalize_ntpath(wchar_t *wbuf)
+{
+	int i;
+	/* fix absolute path prefixes */
+	if (wbuf[0] == '\\') {
+		/* strip NT namespace prefixes */
+		if (!wcsncmp(wbuf, L"\\??\\", 4) ||
+		    !wcsncmp(wbuf, L"\\\\?\\", 4))
+			wbuf += 4;
+		else if (!wcsnicmp(wbuf, L"\\DosDevices\\", 12))
+			wbuf += 12;
+		/* replace remaining '...UNC\' with '\\' */
+		if (!wcsnicmp(wbuf, L"UNC\\", 4)) {
+			wbuf += 2;
+			*wbuf = '\\';
+		}
+	}
+	/* convert backslashes to slashes */
+	for (i = 0; wbuf[i]; i++)
+		if (wbuf[i] == '\\')
+			wbuf[i] = '/';
+	return wbuf;
+}
+
 int mingw_unlink(const char *pathname)
 {
 	int ret, tries = 0;
@@ -918,8 +943,29 @@ struct tm *localtime_r(const time_t *timep, struct tm *result)
 
 char *mingw_getcwd(char *pointer, int len)
 {
-	wchar_t wpointer[MAX_PATH];
-	if (!_wgetcwd(wpointer, ARRAY_SIZE(wpointer)))
+	wchar_t cwd[MAX_PATH], wpointer[MAX_PATH];
+	DWORD ret = GetCurrentDirectoryW(ARRAY_SIZE(cwd), cwd);
+
+	if (!ret || ret >= ARRAY_SIZE(cwd)) {
+		errno = ret ? ENAMETOOLONG : err_win_to_posix(GetLastError());
+		return NULL;
+	}
+	ret = GetLongPathNameW(cwd, wpointer, ARRAY_SIZE(wpointer));
+	if (!ret && GetLastError() == ERROR_ACCESS_DENIED) {
+		HANDLE hnd = CreateFileW(cwd, 0,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+		if (hnd == INVALID_HANDLE_VALUE)
+			return NULL;
+		ret = GetFinalPathNameByHandleW(hnd, wpointer, ARRAY_SIZE(wpointer), 0);
+		CloseHandle(hnd);
+		if (!ret || ret >= ARRAY_SIZE(wpointer))
+			return NULL;
+		if (xwcstoutf(pointer, normalize_ntpath(wpointer), len) < 0)
+			return NULL;
+		return pointer;
+	}
+	if (!ret || ret >= ARRAY_SIZE(wpointer))
 		return NULL;
 	if (xwcstoutf(pointer, wpointer, len) < 0)
 		return NULL;