path: use proper size for win32 api calls

src/path.c

@@ -21,6 +21,8 @@
 #include <stdio.h>
 #include <ctype.h>
 
+extern bool git_win32_longpaths_support;
+
 static int dos_drive_prefix_length(const char *path)
 {
 	int i;
@@ -1253,14 +1255,16 @@ int git_path_diriter_init(
 static int diriter_update_paths(git_path_diriter *diriter)
 {
 	size_t filename_len, path_len;
-
+	size_t max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
 	filename_len = wcslen(diriter->current.cFileName);
 
 	if (GIT_ADD_SIZET_OVERFLOW(&path_len, diriter->parent_len, filename_len) ||
 		GIT_ADD_SIZET_OVERFLOW(&path_len, path_len, 2))
 		return -1;
 
-	if (path_len > GIT_WIN_PATH_UTF16) {
+	if (path_len > max_path_utf16_length) {
 		git_error_set(GIT_ERROR_FILESYSTEM,
 			"invalid path '%.*ls\\%ls' (path too long)",
 			diriter->parent_len, diriter->path, diriter->current.cFileName);

src/win32/path_w32.c

@@ -88,9 +88,6 @@ int git_win32_path_canonicalize(git_win32_path path)
 {
 	wchar_t *base, *from, *to, *next;
 	size_t len;
-	size_t max_path_length = git_win32_longpaths_support
-		? GIT_WIN_PATH_UTF16
-		: GIT_WIN_SHORT_PATH_UTF16;
 
 	base = to = path__skip_prefix(path);
 
@@ -147,22 +144,20 @@ int git_win32_path_canonicalize(git_win32_path path)
 	while (to > base && to[-1] == L'\\') to--;
 
 	*to = L'\0';
-	len = to - path;
-	if (len >= 8 && wcsncmp(L"\\\\?\\UNC\\", path, 8) != 0) {
-		/* Not a UNC path, max length shorter by 2 */
-		max_path_length -= 2;
-	}
-	if (len >= max_path_length) {
+	if ((to - path) > INT_MAX) {
 		SetLastError(ERROR_FILENAME_EXCED_RANGE);
 		return -1;
 	}
 
-	return (int)len;
+	return (int)(to - path);
 }
 
 int git_win32_path__cwd(wchar_t *out, size_t len)
 {
 	int cwd_len;
+	int max_path_length = git_win32_longpaths_support
+		? WIN_GIT_PATH_MAX
+		: WIN_GIT_SHORT_PATH_MAX;
 
 	if (len > INT_MAX) {
 		errno = ENAMETOOLONG;
@@ -179,7 +174,7 @@ int git_win32_path__cwd(wchar_t *out, size_t len)
 		 * '\'s, but we we add a 'UNC' specifier to the path, plus
 		 * a trailing directory separator, plus a NUL.
 		 */
-		if (cwd_len > WIN_GIT_PATH_MAX - 4) {
+		if (cwd_len > max_path_length - 4) {
 			errno = ENAMETOOLONG;
 			return -1;
 		}
@@ -196,7 +191,7 @@ int git_win32_path__cwd(wchar_t *out, size_t len)
 	 * working directory.  (One character for the directory separator,
 	 * one for the null.
 	 */
-	else if (cwd_len > WIN_GIT_PATH_MAX - 2) {
+	else if (cwd_len > max_path_length - 2) {
 		errno = ENAMETOOLONG;
 		return -1;
 	}
@@ -207,20 +202,23 @@ int git_win32_path__cwd(wchar_t *out, size_t len)
 int git_win32_path_from_utf8(git_win32_path out, const char *src)
 {
 	wchar_t *dest = out;
+	size_t max_path_length = git_win32_longpaths_support
+		? WIN_GIT_PATH_MAX
+		: WIN_GIT_SHORT_PATH_MAX;
 
 	/* All win32 paths are in NT-prefixed format, beginning with "\\?\". */
 	memcpy(dest, PATH__NT_NAMESPACE, sizeof(wchar_t) * PATH__NT_NAMESPACE_LEN);
 	dest += PATH__NT_NAMESPACE_LEN;
 
 	/* See if this is an absolute path (beginning with a drive letter) */
 	if (git_path_is_absolute(src)) {
-		if (git__utf8_to_16(dest, WIN_GIT_PATH_MAX, src) < 0)
+		if (git__utf8_to_16(dest, max_path_length, src) < 0)
 			goto on_error;
 	}
 	/* File-prefixed NT-style paths beginning with \\?\ */
 	else if (path__is_nt_namespace(src)) {
 		/* Skip the NT prefix, the destination already contains it */
-		if (git__utf8_to_16(dest, WIN_GIT_PATH_MAX, src + PATH__NT_NAMESPACE_LEN) < 0)
+		if (git__utf8_to_16(dest, max_path_length, src + PATH__NT_NAMESPACE_LEN) < 0)
 			goto on_error;
 	}
 	/* UNC paths */
@@ -229,12 +227,12 @@ int git_win32_path_from_utf8(git_win32_path out, const char *src)
 		dest += 4;
 
 		/* Skip the leading "\\" */
-		if (git__utf8_to_16(dest, WIN_GIT_PATH_MAX - 2, src + 2) < 0)
+		if (git__utf8_to_16(dest, max_path_length - 2, src + 2) < 0)
 			goto on_error;
 	}
 	/* Absolute paths omitting the drive letter */
 	else if (path__startswith_slash(src)) {
-		if (path__cwd(dest, WIN_GIT_MAX_PATH) < 0)
+		if (path__cwd(dest, (int)max_path_length) < 0)
 			goto on_error;
 
 		if (!git_path_is_absolute(dest)) {
@@ -243,19 +241,19 @@ int git_win32_path_from_utf8(git_win32_path out, const char *src)
 		}
 
 		/* Skip the drive letter specification ("C:") */
-		if (git__utf8_to_16(dest + 2, WIN_GIT_PATH_MAX - 2, src) < 0)
+		if (git__utf8_to_16(dest + 2, max_path_length - 2, src) < 0)
 			goto on_error;
 	}
 	/* Relative paths */
 	else {
 		int cwd_len;
 
-		if ((cwd_len = git_win32_path__cwd(dest, WIN_GIT_PATH_MAX)) < 0)
+		if ((cwd_len = git_win32_path__cwd(dest, max_path_length)) < 0)
 			goto on_error;
 
 		dest[cwd_len++] = L'\\';
 
-		if (git__utf8_to_16(dest + cwd_len, WIN_GIT_PATH_MAX - cwd_len, src) < 0)
+		if (git__utf8_to_16(dest + cwd_len, max_path_length - cwd_len, src) < 0)
 			goto on_error;
 	}
 
@@ -273,6 +271,9 @@ int git_win32_path_relative_from_utf8(git_win32_path out, const char *src)
 {
 	wchar_t *dest = out, *p;
 	int len;
+	size_t max_path_length = git_win32_longpaths_support
+		? WIN_GIT_PATH_MAX
+		: WIN_GIT_SHORT_PATH_MAX;
 
 	/* Handle absolute paths */
 	if (git_path_is_absolute(src) ||
@@ -282,7 +283,7 @@ int git_win32_path_relative_from_utf8(git_win32_path out, const char *src)
 		return git_win32_path_from_utf8(out, src);
 	}
 
-	if ((len = git__utf8_to_16(dest, WIN_GIT_MAX_PATH, src)) < 0)
+	if ((len = git__utf8_to_16(dest, max_path_length, src)) < 0)
 		return -1;
 
 	for (p = dest; p < (dest + len); p++) {
@@ -325,16 +326,19 @@ char *git_win32_path_8dot3_name(const char *path)
 	wchar_t *start;
 	char *shortname;
 	int len, namelen = 1;
+	int max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
 
 	if (git_win32_path_from_utf8(longpath, path) < 0)
 		return NULL;
 
-	len = GetShortPathNameW(longpath, shortpath, GIT_WIN_PATH_UTF16);
+	len = GetShortPathNameW(longpath, shortpath, max_path_utf16_length);
 
 	while (len && shortpath[len-1] == L'\\')
 		shortpath[--len] = L'\0';
 
-	if (len == 0 || len >= GIT_WIN_PATH_UTF16)
+	if (len == 0 || len >= max_path_utf16_length)
 		return NULL;
 
 	for (start = shortpath + (len - 1);
@@ -370,6 +374,9 @@ int git_win32_path_readlink_w(git_win32_path dest, const git_win32_path path)
 	DWORD ioctl_ret;
 	wchar_t *target;
 	size_t target_len;
+	size_t max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
 
 	int error = -1;
 
@@ -416,7 +423,7 @@ int git_win32_path_readlink_w(git_win32_path dest, const git_win32_path path)
 
 		/* Need one additional character in the target buffer
 		 * for the terminating NULL. */
-		if (GIT_WIN_PATH_UTF16 > target_len) {
+		if (max_path_utf16_length > target_len) {
 			wcscpy(dest, target);
 			error = (int)target_len;
 		}

src/win32/posix_w32.c

@@ -46,6 +46,7 @@
 unsigned long git_win32__createfile_sharemode =
  FILE_SHARE_READ | FILE_SHARE_WRITE;
 int git_win32__retries = 10;
+extern bool git_win32_longpaths_support;
 
 GIT_INLINE(void) set_errno(void)
 {
@@ -637,7 +638,10 @@ int p_futimes(int fd, const struct p_timeval times[2])
 int p_getcwd(char *buffer_out, size_t size)
 {
 	git_win32_path buf;
-	wchar_t *cwd = _wgetcwd(buf, GIT_WIN_PATH_UTF16);
+	int max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
+	wchar_t *cwd = _wgetcwd(buf, max_path_utf16_length);
 
 	if (!cwd)
 		return -1;
@@ -663,6 +667,9 @@ static int getfinalpath_w(
 {
 	HANDLE hFile;
 	DWORD dwChars;
+	DWORD max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
 
 	/* Use FILE_FLAG_BACKUP_SEMANTICS so we can open a directory. Do not
 	* specify FILE_FLAG_OPEN_REPARSE_POINT; we want to open a handle to the
@@ -674,10 +681,10 @@ static int getfinalpath_w(
 		return -1;
 
 	/* Call GetFinalPathNameByHandle */
-	dwChars = GetFinalPathNameByHandleW(hFile, dest, GIT_WIN_PATH_UTF16, FILE_NAME_NORMALIZED);
+	dwChars = GetFinalPathNameByHandleW(hFile, dest, max_path_utf16_length, FILE_NAME_NORMALIZED);
 	CloseHandle(hFile);
 
-	if (!dwChars || dwChars >= GIT_WIN_PATH_UTF16)
+	if (!dwChars || dwChars >= max_path_utf16_length)
 		return -1;
 
 	/* The path may be delivered to us with a namespace prefix; remove */
@@ -780,14 +787,17 @@ int p_rmdir(const char* path)
 char *p_realpath(const char *orig_path, char *buffer)
 {
 	git_win32_path orig_path_w, buffer_w;
+	DWORD max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
 
 	if (git_win32_path_from_utf8(orig_path_w, orig_path) < 0)
 		return NULL;
 
 	/* Note that if the path provided is a relative path, then the current directory
 	 * is used to resolve the path -- which is a concurrency issue because the current
 	 * directory is a process-wide variable. */
-	if (!GetFullPathNameW(orig_path_w, GIT_WIN_PATH_UTF16, buffer_w, NULL)) {
+	if (!GetFullPathNameW(orig_path_w, max_path_utf16_length, buffer_w, NULL)) {
 		if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
 			errno = ENAMETOOLONG;
 		else

src/win32/w32_util.c

@@ -7,6 +7,8 @@
 
 #include "w32_util.h"
 
+extern bool git_win32_longpaths_support;
+
 /**
  * Creates a FindFirstFile(Ex) filter string from a UTF-8 path.
  * The filter string enumerates all items in the directory.
@@ -19,6 +21,9 @@ bool git_win32__findfirstfile_filter(git_win32_path dest, const char *src)
 {
 	static const wchar_t suffix[] = L"\\*";
 	int len = git_win32_path_from_utf8(dest, src);
+	size_t max_path_utf16_length = git_win32_longpaths_support
+		? GIT_WIN_PATH_UTF16
+		: GIT_WIN_SHORT_PATH_UTF16;
 
 	/* Ensure the path was converted */
 	if (len < 0)
@@ -35,7 +40,7 @@ bool git_win32__findfirstfile_filter(git_win32_path dest, const char *src)
 	}
 
 	/* Ensure we have enough room to add the suffix */
-	if ((size_t)len >= GIT_WIN_PATH_UTF16 - CONST_STRLEN(suffix))
+	if ((size_t)len >= max_path_utf16_length - CONST_STRLEN(suffix))
 		return false;
 
 	wcscat(dest, suffix);