conn->want conversion: Fix fuse_apply_conn_info_opts()

fuse_apply_conn_info_opts() was applying to 'want_ext',
which would cause conflicts with 'want' if the application
applied its own flags to 'conn->want'.

Solution is:
    - to move fuse_{set,unset,get}_feature_flag and
      convert_to_conn_want_ext() to fuse_lowlevel.c and
      to define them as part of the public API, although
      convert_to_conn_want_ext() should not be used - it is
      currently needed to be a public function due as it needs
      to be defined for the tests.

Related to https://github.com/libfuse/libfuse/issues/1171 and
https://github.com/libfuse/libfuse/pull/1172.

Closes: https://github.com/libfuse/libfuse/issues/1171
Signed-off-by: Bernd Schubert <bschubert@ddn.com>

1 files changed, 57 insertions, 40 deletions

diff --git a/test/test_want_conversion.c b/test/test_want_conversion.c
index bee23cc..db731ed 100644
--- a/test/test_want_conversion.c
+++ b/test/test_want_conversion.c
@@ -1,16 +1,22 @@
-#include "util.h"
 #define FUSE_USE_VERSION FUSE_MAKE_VERSION(3, 17)
 
+#include "util.h"
 #include "fuse_i.h"
+#include "fuse_lowlevel.h"
 #include <stdio.h>
 #include <assert.h>
 #include <inttypes.h>
 #include <stdbool.h>
+#include <err.h>
 
 static void print_conn_info(const char *prefix, struct fuse_conn_info *conn)
 {
-	printf("%s: want=0x%" PRIx32 " want_ext=0x%" PRIx64 "\n", prefix,
-	       conn->want, conn->want_ext);
+	struct fuse_session *se = container_of(conn, struct fuse_session, conn);
+
+	printf("%s: want=0x%" PRIx32 " want_ext=0x%" PRIx64
+		" want_default=0x%" PRIx32 " want_ext_default=0x%" PRIx64 "\n",
+		prefix, conn->want, conn->want_ext, se->conn_want,
+		se->conn_want_ext);
 }
 
 static void application_init_old_style(struct fuse_conn_info *conn)
@@ -18,33 +24,31 @@ static void application_init_old_style(struct fuse_conn_info *conn)
 	/* Simulate application init the old style */
 	conn->want |= FUSE_CAP_ASYNC_READ;
 	conn->want &= ~FUSE_CAP_SPLICE_READ;
+
+	/*
+	 * Also use new style API, as that might happen through
+	 * fuse_apply_conn_info_opts()
+	 */
+	fuse_set_feature_flag(conn, FUSE_CAP_IOCTL_DIR);
 }
 
 static void application_init_new_style(struct fuse_conn_info *conn)
 {
 	/* Simulate application init the new style */
 	fuse_set_feature_flag(conn, FUSE_CAP_ASYNC_READ);
+	fuse_set_feature_flag(conn, FUSE_CAP_IOCTL_DIR);
 	fuse_unset_feature_flag(conn, FUSE_CAP_SPLICE_READ);
 }
 
 static void test_fuse_fs_init(struct fuse_conn_info *conn, bool new_style)
 {
-	uint64_t want_ext_default = conn->want_ext;
-	uint32_t want_default = fuse_lower_32_bits(conn->want_ext);
-	int rc;
-
 	/* High-level init */
 	fuse_set_feature_flag(conn, FUSE_CAP_EXPORT_SUPPORT);
 
-	conn->want = want_default;
-
 	if (new_style)
 		application_init_new_style(conn);
 	else
 		application_init_old_style(conn);
-
-	rc = convert_to_conn_want_ext(conn, want_ext_default, want_default);
-	assert(rc == 0);
 }
 
 static void test_do_init(struct fuse_conn_info *conn, bool new_style)
@@ -53,49 +57,71 @@ static void test_do_init(struct fuse_conn_info *conn, bool new_style)
 	conn->capable_ext = FUSE_CAP_SPLICE_READ | FUSE_CAP_SPLICE_WRITE |
 			    FUSE_CAP_SPLICE_MOVE | FUSE_CAP_POSIX_LOCKS |
 			    FUSE_CAP_FLOCK_LOCKS | FUSE_CAP_EXPORT_SUPPORT |
-			    FUSE_CAP_ASYNC_READ;
+			    FUSE_CAP_ASYNC_READ | FUSE_CAP_IOCTL_DIR;
 	conn->capable = fuse_lower_32_bits(conn->capable_ext);
-	conn->want_ext = conn->capable_ext;
+
+	fuse_set_feature_flag(conn, FUSE_CAP_SPLICE_READ |
+				    FUSE_CAP_SPLICE_WRITE |
+				    FUSE_CAP_SPLICE_MOVE);
 
 	print_conn_info("Initial state", conn);
 
-	uint64_t want_ext_default = conn->want_ext;
-	uint32_t want_default = fuse_lower_32_bits(conn->want_ext);
 	int rc;
 
-	conn->want = want_default;
-	conn->capable = fuse_lower_32_bits(conn->capable_ext);
-
 	test_fuse_fs_init(conn, new_style);
+	print_conn_info("After init", conn);
 
-	rc = convert_to_conn_want_ext(conn, want_ext_default, want_default);
+	rc = fuse_convert_to_conn_want_ext(conn);
 	assert(rc == 0);
 
 	/* Verify all expected flags are set */
 	assert(!(conn->want_ext & FUSE_CAP_SPLICE_READ));
 	assert(conn->want_ext & FUSE_CAP_SPLICE_WRITE);
 	assert(conn->want_ext & FUSE_CAP_SPLICE_MOVE);
-	assert(conn->want_ext & FUSE_CAP_POSIX_LOCKS);
-	assert(conn->want_ext & FUSE_CAP_FLOCK_LOCKS);
 	assert(conn->want_ext & FUSE_CAP_EXPORT_SUPPORT);
 	assert(conn->want_ext & FUSE_CAP_ASYNC_READ);
+	assert(conn->want_ext & FUSE_CAP_IOCTL_DIR);
+
 	/* Verify no other flags are set */
 	assert(conn->want_ext ==
 	       (FUSE_CAP_SPLICE_WRITE | FUSE_CAP_SPLICE_MOVE |
-		FUSE_CAP_POSIX_LOCKS | FUSE_CAP_FLOCK_LOCKS |
-		FUSE_CAP_EXPORT_SUPPORT | FUSE_CAP_ASYNC_READ));
+		FUSE_CAP_EXPORT_SUPPORT | FUSE_CAP_ASYNC_READ |
+		FUSE_CAP_IOCTL_DIR));
 
 	print_conn_info("After init", conn);
 }
 
 static void test_want_conversion_basic(void)
 {
-	struct fuse_conn_info conn = { 0 };
+	const struct fuse_lowlevel_ops ops = { 0 };
+	struct fuse_args args = FUSE_ARGS_INIT(0, NULL);
+	struct fuse_session *se;
+	struct fuse_conn_info *conn;
+
+	/* Add the program name to arg[0] */
+	if (fuse_opt_add_arg(&args, "test_signals")) {
+		fprintf(stderr, "Failed to add argument\n");
+		errx(1, "Failed to add argument");
+	}
+
+
+	se = fuse_session_new(&args, &ops, sizeof(ops), NULL);
+	assert(se);
+	conn = &se->conn;
+	printf("\nTesting basic want conversion, old style:\n");
+	test_do_init(conn, false);
+	fuse_session_destroy(se);
+
+	se = fuse_session_new(&args, &ops, sizeof(ops), NULL);
+	assert(se);
+	conn = &se->conn;
+	printf("\nTesting basic want conversion, new style:\n");
+	test_do_init(conn, true);
+	print_conn_info("After init", conn);
+	fuse_session_destroy(se);
+
+	fuse_opt_free_args(&args);
 
-	printf("\nTesting basic want conversion:\n");
-	test_do_init(&conn, false);
-	test_do_init(&conn, true);
-	print_conn_info("After init", &conn);
 }
 
 static void test_want_conversion_conflict(void)
@@ -115,16 +141,11 @@ static void test_want_conversion_conflict(void)
 	conn.want = fuse_lower_32_bits(conn.want_ext);
 	print_conn_info("Test conflict initial", &conn);
 
-	/* Initialize default values like in basic test */
-	uint64_t want_ext_default_ll = conn.want_ext;
-	uint32_t want_default_ll = fuse_lower_32_bits(want_ext_default_ll);
-
 	/* Simulate application init modifying capabilities */
 	conn.want_ext |= FUSE_CAP_ATOMIC_O_TRUNC; /* Add new capability */
 	conn.want &= ~FUSE_CAP_SPLICE_READ; /* Remove a capability */
 
-	rc = convert_to_conn_want_ext(&conn, want_ext_default_ll,
-				      want_default_ll);
+	rc = fuse_convert_to_conn_want_ext(&conn);
 	assert(rc == -EINVAL);
 	print_conn_info("Test conflict after", &conn);
 
@@ -143,11 +164,7 @@ static void test_want_conversion_high_bits(void)
 	conn.want = fuse_lower_32_bits(conn.want_ext);
 	print_conn_info("Test high bits initial", &conn);
 
-	uint64_t want_ext_default_ll = conn.want_ext;
-	uint32_t want_default_ll = fuse_lower_32_bits(want_ext_default_ll);
-
-	rc = convert_to_conn_want_ext(&conn, want_ext_default_ll,
-				      want_default_ll);
+	rc = fuse_convert_to_conn_want_ext(&conn);
 	assert(rc == 0);
 	assert(conn.want_ext == ((1ULL << 33) | FUSE_CAP_ASYNC_READ));
 	print_conn_info("Test high bits after", &conn);