libsquashfs: Add sqfs_open_native_file function

Having a function to interpret the flags and open a native file handle
simplifies the istream/ostream/file code which shares that decoding
part, particularly on windows where the character set needs to be
transformed.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

2 files changed, 6 insertions, 37 deletions

diff --git a/lib/io/src/win32/istream.c b/lib/io/src/win32/istream.c
index e6cb266..7cc7144 100644
--- a/lib/io/src/win32/istream.c
+++ b/lib/io/src/win32/istream.c
@@ -154,25 +154,14 @@ fail_free:
 
 sqfs_istream_t *istream_open_file(const char *path)
 {
-	WCHAR *wpath = NULL;
+	sqfs_file_handle_t hnd;
 	sqfs_istream_t *out;
-	HANDLE hnd;
-
-	wpath = path_to_windows(path);
-	if (wpath == NULL)
-		return NULL;
 
-	hnd = CreateFileW(wpath, GENERIC_READ, FILE_SHARE_READ, NULL,
-			  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
-
-	if (hnd == INVALID_HANDLE_VALUE) {
+	if (sqfs_open_native_file(&hnd, path, SQFS_FILE_OPEN_READ_ONLY)) {
 		w32_perror(path);
-		free(wpath);
 		return NULL;
 	}
 
-	free(wpath);
-
 	out = istream_open_handle(path, hnd);
 	if (out == NULL)
 		CloseHandle(hnd);
diff --git a/lib/io/src/win32/ostream.c b/lib/io/src/win32/ostream.c
index 5b099a4..5b584e5 100644
--- a/lib/io/src/win32/ostream.c
+++ b/lib/io/src/win32/ostream.c
@@ -176,39 +176,19 @@ fail_free:
 
 sqfs_ostream_t *ostream_open_file(const char *path, int flags)
 {
-	int access_flags, creation_mode;
-	WCHAR *wpath = NULL;
+	sqfs_file_handle_t hnd;
 	sqfs_ostream_t *out;
-	HANDLE hnd;
-
-	access_flags = GENERIC_WRITE;
-
-	if (flags & SQFS_FILE_OPEN_OVERWRITE) {
-		creation_mode = CREATE_ALWAYS;
-	} else {
-		creation_mode = CREATE_NEW;
-	}
 
-	if (flags & SQFS_FILE_OPEN_NO_CHARSET_XFRM) {
-		hnd = CreateFileA(path, access_flags, 0, NULL, creation_mode,
-				  FILE_ATTRIBUTE_NORMAL, NULL);
-	} else {
-		wpath = path_to_windows(path);
-		if (wpath == NULL)
-			return NULL;
-
-		hnd = CreateFileW(wpath, access_flags, 0, NULL, creation_mode,
-				  FILE_ATTRIBUTE_NORMAL, NULL);
+	if (sqfs_open_native_file(&hnd, path, flags)) {
+		w32_perror(path);
+		return NULL;
 	}
 
 	if (hnd == INVALID_HANDLE_VALUE) {
 		w32_perror(path);
-		free(wpath);
 		return NULL;
 	}
 
-	free(wpath);
-
 	out = ostream_open_handle(path, hnd, flags);
 	if (out == NULL)
 		CloseHandle(hnd);