From: Hilko Bengen <bengen@debian.org>
Date: Tue, 25 Nov 2025 23:26:55 +0100
Subject: Add upstream patches for fuse3 support

---
 m4/libfuse.m4          | 150 ++++++++++++++++++++++++++++++++++---------------
 qcowtools/mount_fuse.c |  38 ++++++++++++-
 qcowtools/mount_fuse.h |  39 +++++++++++--
 qcowtools/qcowmount.c  |  66 +++++++++++++++++++---
 4 files changed, 231 insertions(+), 62 deletions(-)

diff --git a/m4/libfuse.m4 b/m4/libfuse.m4
index a6fc990..eec18d6 100644
--- a/m4/libfuse.m4
+++ b/m4/libfuse.m4
@@ -1,58 +1,86 @@
 dnl Checks for libfuse required headers and functions
 dnl
-dnl Version: 20220118
+dnl Version: 20240413
 
 dnl Function to detect if libfuse is available
 dnl ac_libfuse_dummy is used to prevent AC_CHECK_LIB adding unnecessary -l<library> arguments
 AC_DEFUN([AX_LIBFUSE_CHECK_LIB],
-  [dnl Check if parameters were provided
-  AS_IF(
-    [test "x$ac_cv_with_libfuse" != x && test "x$ac_cv_with_libfuse" != xno && test "x$ac_cv_with_libfuse" != xauto-detect],
-    [AS_IF(
-      [test -d "$ac_cv_with_libfuse"],
-      [CFLAGS="$CFLAGS -I${ac_cv_with_libfuse}/include"
-      LDFLAGS="$LDFLAGS -L${ac_cv_with_libfuse}/lib"],
-      [AC_MSG_WARN([no such directory: $ac_cv_with_libfuse])
-      ])
-    ])
-
-  AS_IF(
-    [test "x$ac_cv_with_libfuse" = xno],
+  [AS_IF(
+    [test "x$ac_cv_enable_shared_libs" = xno || test "x$ac_cv_with_libfuse" = xno],
     [ac_cv_libfuse=no],
-    [dnl Check for a pkg-config file
+    [dnl Check if the directory provided as parameter exists
+    dnl For both --with-libfuse which returns "yes" and --with-libfuse= which returns ""
+    dnl treat them as auto-detection.
     AS_IF(
-      [test "x$cross_compiling" != "xyes" && test "x$PKGCONFIG" != "x"],
-      [PKG_CHECK_MODULES(
-        [fuse],
-        [fuse >= 2.6],
-        [ac_cv_libfuse=libfuse],
-        [ac_cv_libfuse=no])
+      [test "x$ac_cv_with_libfuse" != x && test "x$ac_cv_with_libfuse" != xauto-detect && test "x$ac_cv_with_libfuse" != xyes],
+      [AS_IF(
+        [test -d "$ac_cv_with_libfuse"],
+        [CFLAGS="$CFLAGS -I${ac_cv_with_libfuse}/include"
+        LDFLAGS="$LDFLAGS -L${ac_cv_with_libfuse}/lib"],
+        [AC_MSG_FAILURE(
+          [no such directory: $ac_cv_with_libfuse],
+          [1])
+        ])],
+      [dnl Check for a pkg-config file
+      AS_IF(
+        [test "x$cross_compiling" != "xyes" && test "x$PKGCONFIG" != "x"],
+        [PKG_CHECK_MODULES(
+          [fuse3],
+          [fuse3 >= 3.0],
+          [ac_cv_libfuse=libfuse3],
+          [ac_cv_libfuse=no])
+
+        AS_IF(
+          [test "x$ac_cv_libfuse" = xno],
+          [PKG_CHECK_MODULES(
+            [fuse],
+            [fuse >= 2.6],
+            [ac_cv_libfuse=libfuse],
+            [ac_cv_libfuse=no])
+          ])
+
+        AS_IF(
+          [test "x$ac_cv_libfuse" = xlibfuse3],
+          [ac_cv_libfuse_CPPFLAGS="$pkg_cv_fuse3_CFLAGS -D_FILE_OFFSET_BITS=64"
+          ac_cv_libfuse_LIBADD="$pkg_cv_fuse3_LIBS"])
+
+        AS_IF(
+          [test "x$ac_cv_libfuse" = xlibfuse],
+          [ac_cv_libfuse_CPPFLAGS="$pkg_cv_fuse_CFLAGS -D_FILE_OFFSET_BITS=64"
+          ac_cv_libfuse_LIBADD="$pkg_cv_fuse_LIBS"])
+        ])
       ])
 
+    backup_CPPFLAGS="$CPPFLAGS"
+
+    dnl Check for libfuse and libfuse3
     AS_IF(
-      [test "x$ac_cv_libfuse" = xlibfuse],
-      [ac_cv_libfuse_CPPFLAGS="$pkg_cv_fuse_CFLAGS"
-      ac_cv_libfuse_LIBADD="$pkg_cv_fuse_LIBS"],
+      [test "x$ac_cv_libfuse" != xlibfuse && test "x$ac_cv_libfuse" != xlibfuse3],
       [dnl Check for headers
-      AC_CHECK_HEADERS(
-        [fuse.h],
-        [ac_cv_header_fuse_h=yes],
-        [ac_cv_header_fuse_h=no])
 
-      dnl libfuse sometimes requires -D_FILE_OFFSET_BITS=64 to be set
-      dnl macFuse requires -DFUSE_USE_VERSION=26 to be set
+      CPPFLAGS="$backup_CPPFLAGS -DFUSE_USE_VERSION=30"
+      AC_CHECK_HEADERS([fuse.h])
+
       AS_IF(
-        [test "x$ac_cv_header_fuse_h" = xno],
-        [AS_UNSET([ac_cv_header_fuse_h])
-        CPPFLAGS="$CPPFLAGS -D_FILE_OFFSET_BITS=64 -DFUSE_USE_VERSION=26"
+        [test "x$ac_cv_header_fuse_h" = xyes],
+        [ac_cv_libfuse=libfuse3],
+        [CPPFLAGS="$backup_CPPFLAGS -DFUSE_USE_VERSION=26"
         AC_CHECK_HEADERS([fuse.h])
-      ])
+
+        AS_IF(
+          [test "x$ac_cv_header_fuse_h" = xyes],
+          [ac_cv_libfuse=libfuse])
+        ])
 
       AS_IF(
         [test "x$ac_cv_header_fuse_h" = xno],
         [ac_cv_libfuse=no],
         [dnl Check for the individual functions
-        ac_cv_libfuse=libfuse
+        AC_CHECK_LIB(
+          fuse,
+          fuse_invalidate,
+          [ac_cv_libfuse=libfuse],
+          [ac_cv_libfuse=libfuse3])
 
         AC_CHECK_LIB(
           fuse,
@@ -75,24 +103,22 @@ AC_DEFUN([AX_LIBFUSE_CHECK_LIB],
           [ac_cv_libfuse_dummy=yes],
           [ac_cv_libfuse=no])
 
-        ac_cv_libfuse_LIBADD="-lfuse";
+        dnl libfuse and libfuse3 require -D_FILE_OFFSET_BITS=64 to be set
+        ac_cv_libfuse_CPPFLAGS="-D_FILE_OFFSET_BITS=64"
+
+        AS_IF(
+          [test "x$ac_cv_libfuse" = xlibfuse3],
+          [ac_cv_libfuse_LIBADD="-lfuse3"],
+          [ac_cv_libfuse_LIBADD="-lfuse"])
         ])
       ])
 
     dnl Check for libosxfuse
     AS_IF(
       [test "x$ac_cv_with_libfuse" != xno && test "x$ac_cv_header_fuse_h" = xno],
-      [CPPFLAGS="$CPPFLAGS -DFUSE_USE_VERSION=26"
+      [CPPFLAGS="$backup_CPPFLAGS -DFUSE_USE_VERSION=26"
       AC_CHECK_HEADERS([osxfuse/fuse.h])
 
-      dnl libosxfuse sometimes requires -D_FILE_OFFSET_BITS=64 to be set
-      AS_IF(
-        [test "x$ac_cv_header_osxfuse_fuse_h" = xno],
-        [AS_UNSET([ac_cv_header_osxfuse_fuse_h])
-        CPPFLAGS="$CPPFLAGS -D_FILE_OFFSET_BITS=64"
-        AC_CHECK_HEADERS([osxfuse/fuse.h])
-      ])
-
       AS_IF(
         [test "x$ac_cv_header_osxfuse_fuse_h" = xno],
         [ac_cv_libfuse=no],
@@ -120,9 +146,21 @@ AC_DEFUN([AX_LIBFUSE_CHECK_LIB],
           [ac_cv_libfuse_dummy=yes],
           [ac_cv_libfuse=no])
 
+        dnl libosxfuse requires -D_FILE_OFFSET_BITS=64 to be set
+        ac_cv_libfuse_CPPFLAGS="-D_FILE_OFFSET_BITS=64"
+
         ac_cv_libfuse_LIBADD="-losxfuse";
         ])
       ])
+
+    AS_IF(
+      [test "x$ac_cv_libfuse" != xyes && test "x$ac_cv_with_libfuse" != x && test "x$ac_cv_with_libfuse" != xauto-detect && test "x$ac_cv_with_libfuse" != xyes],
+      [AC_MSG_FAILURE(
+        [unable to find supported libfuse in directory: $ac_cv_with_libfuse],
+        [1])
+      ])
+
+    CPPFLAGS="$backup_CPPFLAGS"
     ])
 
   AS_IF(
@@ -132,6 +170,13 @@ AC_DEFUN([AX_LIBFUSE_CHECK_LIB],
       [1],
       [Define to 1 if you have the 'fuse' library (-lfuse).])
     ])
+  AS_IF(
+    [test "x$ac_cv_libfuse" = xlibfuse3],
+    [AC_DEFINE(
+      [HAVE_LIBFUSE3],
+      [1],
+      [Define to 1 if you have the 'fuse3' library (-lfuse3).])
+    ])
   AS_IF(
     [test "x$ac_cv_libfuse" = xlibosxfuse],
     [AC_DEFINE(
@@ -182,6 +227,12 @@ AC_DEFUN([AX_LIBFUSE_CHECK_ENABLE],
       [ax_libfuse_pc_libs_private],
       [-lfuse])
     ])
+  AS_IF(
+    [test "x$ac_cv_libfuse" = xlibfuse3],
+    [AC_SUBST(
+      [ax_libfuse_pc_libs_private],
+      [-lfuse3])
+    ])
   AS_IF(
     [test "x$ac_cv_libfuse" = xlibosxfuse],
     [AC_SUBST(
@@ -198,5 +249,14 @@ AC_DEFUN([AX_LIBFUSE_CHECK_ENABLE],
       [ax_libfuse_spec_build_requires],
       [fuse-devel])
     ])
+  AS_IF(
+    [test "x$ac_cv_libfuse" = xlibfuse3],
+    [AC_SUBST(
+      [ax_libfuse_spec_requires],
+      [fuse3-libs])
+    AC_SUBST(
+      [ax_libfuse_spec_build_requires],
+      [fuse3-devel])
+    ])
   ])
 
diff --git a/qcowtools/mount_fuse.c b/qcowtools/mount_fuse.c
index c035b3d..4116340 100644
--- a/qcowtools/mount_fuse.c
+++ b/qcowtools/mount_fuse.c
@@ -44,7 +44,7 @@
 
 extern mount_handle_t *qcowmount_mount_handle;
 
-#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE )
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE )
 
 #if ( SIZEOF_OFF_T != 8 ) && ( SIZEOF_OFF_T != 4 )
 #error Size of off_t not supported
@@ -255,11 +255,20 @@ int mount_fuse_filldir(
 
 		return( -1 );
 	}
+#if defined( HAVE_LIBFUSE3 )
+	if( filler(
+	     buffer,
+	     name,
+	     stat_info,
+	     0,
+	     0 ) == 1 )
+#else
 	if( filler(
 	     buffer,
 	     name,
 	     stat_info,
 	     0 ) == 1 )
+#endif
 	{
 		libcerror_error_set(
 		 error,
@@ -655,12 +664,22 @@ on_error:
 /* Reads a directory
  * Returns 0 if successful or a negative errno value otherwise
  */
+#if defined( HAVE_LIBFUSE3 )
+int mount_fuse_readdir(
+     const char *path,
+     void *buffer,
+     fuse_fill_dir_t filler,
+     off_t offset QCOWTOOLS_ATTRIBUTE_UNUSED,
+     struct fuse_file_info *file_info QCOWTOOLS_ATTRIBUTE_UNUSED,
+     enum fuse_readdir_flags flags QCOWTOOLS_ATTRIBUTE_UNUSED )
+#else
 int mount_fuse_readdir(
      const char *path,
      void *buffer,
      fuse_fill_dir_t filler,
      off_t offset QCOWTOOLS_ATTRIBUTE_UNUSED,
      struct fuse_file_info *file_info QCOWTOOLS_ATTRIBUTE_UNUSED )
+#endif
 {
 	struct stat *stat_info                = NULL;
 	libcerror_error_t *error              = NULL;
@@ -675,6 +694,10 @@ int mount_fuse_readdir(
 
 	QCOWTOOLS_UNREFERENCED_PARAMETER( offset )
 
+#if defined( HAVE_LIBFUSE3 )
+	QCOWTOOLS_UNREFERENCED_PARAMETER( flags )
+#endif
+
 #if defined( HAVE_DEBUG_OUTPUT )
 	if( libcnotify_verbose != 0 )
 	{
@@ -1044,9 +1067,16 @@ on_error:
 /* Retrieves the file stat info
  * Returns 0 if successful or a negative errno value otherwise
  */
+#if defined( HAVE_LIBFUSE3 )
+int mount_fuse_getattr(
+     const char *path,
+     struct stat *stat_info,
+     struct fuse_file_info *file_info QCOWTOOLS_ATTRIBUTE_UNUSED )
+#else
 int mount_fuse_getattr(
      const char *path,
      struct stat *stat_info )
+#endif
 {
 	libcerror_error_t *error       = NULL;
 	mount_file_entry_t *file_entry = NULL;
@@ -1058,6 +1088,10 @@ int mount_fuse_getattr(
 	uint16_t file_mode             = 0;
 	int result                     = 0;
 
+#if defined( HAVE_LIBFUSE3 )
+	QCOWTOOLS_UNREFERENCED_PARAMETER( file_info )
+#endif
+
 #if defined( HAVE_DEBUG_OUTPUT )
 	if( libcnotify_verbose != 0 )
 	{
@@ -1314,5 +1348,5 @@ on_error:
 	return;
 }
 
-#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE ) */
+#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE ) */
 
diff --git a/qcowtools/mount_fuse.h b/qcowtools/mount_fuse.h
index 03f202a..8382e51 100644
--- a/qcowtools/mount_fuse.h
+++ b/qcowtools/mount_fuse.h
@@ -25,17 +25,27 @@
 #include <common.h>
 #include <types.h>
 
-#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE )
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE )
+
+#if !defined( FUSE_USE_VERSION ) && !defined( CYGFUSE )
+
+/* Ensure FUSE_USE_VERSION is defined before including fuse.h
+ */
+#if defined( HAVE_LIBFUSE3 )
+#define FUSE_USE_VERSION	30
+#else
 #define FUSE_USE_VERSION	26
+#endif
 
-#if defined( HAVE_LIBFUSE )
-#include <fuse.h>
+#endif /* !defined( FUSE_USE_VERSION ) && !defined( CYGFUSE ) */
 
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 )
+#include <fuse.h>
 #elif defined( HAVE_LIBOSXFUSE )
 #include <osxfuse/fuse.h>
 #endif
 
-#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE ) */
+#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE ) */
 
 #include "mount_file_entry.h"
 #include "mount_handle.h"
@@ -46,7 +56,7 @@
 extern "C" {
 #endif
 
-#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE )
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE )
 
 int mount_fuse_set_stat_info(
      struct stat *stat_info,
@@ -84,25 +94,42 @@ int mount_fuse_opendir(
      const char *path,
      struct fuse_file_info *file_info );
 
+#if defined( HAVE_LIBFUSE3 )
+int mount_fuse_readdir(
+     const char *path,
+     void *buffer,
+     fuse_fill_dir_t filler,
+     off_t offset,
+     struct fuse_file_info *file_info,
+     enum fuse_readdir_flags flags );
+#else
 int mount_fuse_readdir(
      const char *path,
      void *buffer,
      fuse_fill_dir_t filler,
      off_t offset,
      struct fuse_file_info *file_info );
+#endif
 
 int mount_fuse_releasedir(
      const char *path,
      struct fuse_file_info *file_info );
 
+#if defined( HAVE_LIBFUSE3 )
+int mount_fuse_getattr(
+     const char *path,
+     struct stat *stat_info,
+     struct fuse_file_info *file_info );
+#else
 int mount_fuse_getattr(
      const char *path,
      struct stat *stat_info );
+#endif
 
 void mount_fuse_destroy(
       void *private_data );
 
-#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE ) */
+#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE ) */
 
 #if defined( __cplusplus )
 }
diff --git a/qcowtools/qcowmount.c b/qcowtools/qcowmount.c
index d98d8e1..8252d6e 100644
--- a/qcowtools/qcowmount.c
+++ b/qcowtools/qcowmount.c
@@ -1,5 +1,5 @@
 /*
- * Mounts a QEMU Copy-On-Write (QCOW) image file
+ * Mounts a QEMU Copy-On-Write (QCOW) image file.
  *
  * Copyright (C) 2010-2024, Joachim Metz <joachim.metz@gmail.com>
  *
@@ -146,11 +146,19 @@ int main( int argc, char * const argv[] )
 	int result                                  = 0;
 	int verbose                                 = 0;
 
-#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE )
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE )
 	struct fuse_operations qcowmount_fuse_operations;
 
+#if defined( HAVE_LIBFUSE3 )
+	/* Need to set this to 1 even if there no arguments, otherwise this causes
+	 * fuse: empty argv passed to fuse_session_new()
+	 */
+	char *fuse_argv[ 2 ]                        = { program, NULL };
+	struct fuse_args qcowmount_fuse_arguments   = FUSE_ARGS_INIT(1, fuse_argv);
+#else
 	struct fuse_args qcowmount_fuse_arguments   = FUSE_ARGS_INIT(0, NULL);
 	struct fuse_chan *qcowmount_fuse_channel    = NULL;
+#endif
 	struct fuse *qcowmount_fuse_handle          = NULL;
 
 #elif defined( HAVE_LIBDOKAN )
@@ -353,7 +361,7 @@ int main( int argc, char * const argv[] )
 
 		goto on_error;
 	}
-#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE )
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE )
 	if( option_extended_options != NULL )
 	{
 		/* This argument is required but ignored
@@ -409,6 +417,34 @@ int main( int argc, char * const argv[] )
 	qcowmount_fuse_operations.getattr    = &mount_fuse_getattr;
 	qcowmount_fuse_operations.destroy    = &mount_fuse_destroy;
 
+#if defined( HAVE_LIBFUSE3 )
+	qcowmount_fuse_handle = fuse_new(
+	                         &qcowmount_fuse_arguments,
+	                         &qcowmount_fuse_operations,
+	                         sizeof( struct fuse_operations ),
+	                         qcowmount_mount_handle );
+
+	if( qcowmount_fuse_handle == NULL )
+	{
+		fprintf(
+		 stderr,
+		 "Unable to create fuse handle.\n" );
+
+		goto on_error;
+	}
+	result = fuse_mount(
+	          qcowmount_fuse_handle,
+	          mount_point );
+
+	if( result != 0 )
+	{
+		fprintf(
+		 stderr,
+		 "Unable to fuse mount file system.\n" );
+
+		goto on_error;
+	}
+#else
 	qcowmount_fuse_channel = fuse_mount(
 	                          mount_point,
 	                          &qcowmount_fuse_arguments );
@@ -436,6 +472,8 @@ int main( int argc, char * const argv[] )
 
 		goto on_error;
 	}
+#endif /* defined( HAVE_LIBFUSE3 ) */
+
 	if( verbose == 0 )
 	{
 		if( fuse_daemonize(
@@ -490,10 +528,14 @@ int main( int argc, char * const argv[] )
 
 		goto on_error;
 	}
-	qcowmount_dokan_options.Version     = DOKAN_VERSION;
-	qcowmount_dokan_options.ThreadCount = 0;
-	qcowmount_dokan_options.MountPoint  = mount_point;
+	qcowmount_dokan_options.Version    = DOKAN_VERSION;
+	qcowmount_dokan_options.MountPoint = mount_point;
 
+#if DOKAN_MINIMUM_COMPATIBLE_VERSION >= 200
+	qcowmount_dokan_options.SingleThread = TRUE;
+#else
+	qcowmount_dokan_options.ThreadCount  = 0;
+#endif
 	if( verbose != 0 )
 	{
 		qcowmount_dokan_options.Options |= DOKAN_OPTION_STDERR;
@@ -563,10 +605,16 @@ int main( int argc, char * const argv[] )
 
 #endif /* ( DOKAN_VERSION >= 600 ) && ( DOKAN_VERSION < 800 ) */
 
+#if DOKAN_MINIMUM_COMPATIBLE_VERSION >= 200
+	DokanInit();
+#endif
 	result = DokanMain(
 	          &qcowmount_dokan_options,
 	          &qcowmount_dokan_operations );
 
+#if DOKAN_MINIMUM_COMPATIBLE_VERSION >= 200
+	DokanShutdown();
+#endif
 	switch( result )
 	{
 		case DOKAN_SUCCESS:
@@ -620,11 +668,11 @@ int main( int argc, char * const argv[] )
 #else
 	fprintf(
 	 stderr,
-	 "No sub system to mount QCOW format.\n" );
+	 "No sub system to mount QEMU Copy-On-Write (QCOW) image file format.\n" );
 
 	return( EXIT_FAILURE );
 
-#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE ) */
+#endif /* defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE ) */
 
 on_error:
 	if( error != NULL )
@@ -634,7 +682,7 @@ on_error:
 		libcerror_error_free(
 		 &error );
 	}
-#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBOSXFUSE )
+#if defined( HAVE_LIBFUSE ) || defined( HAVE_LIBFUSE3 ) || defined( HAVE_LIBOSXFUSE )
 	if( qcowmount_fuse_handle != NULL )
 	{
 		fuse_destroy(