Add in the libfuse version a program was compiled with (#942)

The API stays the same, the libfuse version comes from
inlined functions, which are defined fuse_lowlevel.h
and fuse.h. As these inlined functions are defined in the header
files they get added into the application, similar as if these
were preprocessor macros.
Macro vs inlined function is then just a style issue - I personally
prefer the latter.

fuse_session_new() -> static inlinei, in the application
_fuse_session_new -> inside of libfuse

fuse_new() -> static inline, in the application
_fuse_new() -> inside of libfuse

Note: Entirely untested is the fuse 30 api - we need a test
for it. And we do not have any ABI tests at all.

Signed-off-by: Bernd Schubert <bernd.schubert@fastmail.fm>

1 files changed, 65 insertions, 10 deletions

diff --git a/lib/fuse.c b/lib/fuse.c
index f619c00..8617168 100644
--- a/lib/fuse.c
+++ b/lib/fuse.c
@@ -4890,11 +4890,19 @@ void fuse_stop_cleanup_thread(struct fuse *f)
 	}
 }
 
-
-FUSE_SYMVER("fuse_new_31", "fuse_new@@FUSE_3.1")
-struct fuse *fuse_new_31(struct fuse_args *args,
-		      const struct fuse_operations *op,
-		      size_t op_size, void *user_data)
+/*
+ * Not supposed to be called directly, but supposed to be called
+ * through the fuse_new macro
+ */
+struct fuse *_fuse_new_317(struct fuse_args *args,
+			   const struct fuse_operations *op,
+			   size_t op_size, struct libfuse_version *version,
+			   void *user_data);
+FUSE_SYMVER("_fuse_new_317", "_fuse_new@@FUSE_3.17")
+struct fuse *_fuse_new_317(struct fuse_args *args,
+			   const struct fuse_operations *op,
+			   size_t op_size, struct libfuse_version *version,
+			   void *user_data)
 {
 	struct fuse *f;
 	struct node *root;
@@ -4976,7 +4984,7 @@ struct fuse *fuse_new_31(struct fuse_args *args,
 	f->conf.readdir_ino = 1;
 #endif
 
-	f->se = fuse_session_new(args, &llop, sizeof(llop), f);
+	f->se = _fuse_session_new(args, &llop, sizeof(llop), version, f);
 	if (f->se == NULL)
 		goto out_free_fs;
 
@@ -5041,16 +5049,62 @@ out:
 }
 
 /* Emulates 3.0-style fuse_new(), which processes --help */
+struct fuse *_fuse_new_30(struct fuse_args *args, const struct fuse_operations *op,
+			 size_t op_size,
+			 struct libfuse_version *version,
+			 void *user_data);
+FUSE_SYMVER("_fuse_new_30", "_fuse_new@FUSE_3.0")
+struct fuse *_fuse_new_30(struct fuse_args *args,
+			 const struct fuse_operations *op,
+			 size_t op_size,
+			 struct libfuse_version *version,
+			 void *user_data)
+{
+	struct fuse_config conf = {0};
+
+	const struct fuse_opt opts[] = {
+		FUSE_LIB_OPT("-h", show_help, 1),
+		FUSE_LIB_OPT("--help", show_help, 1),
+		FUSE_OPT_END
+	};
+
+	if (fuse_opt_parse(args, &conf, opts,
+			   fuse_lib_opt_proc) == -1)
+		return NULL;
+
+	if (conf.show_help) {
+		fuse_lib_help(args);
+		return NULL;
+	} else
+		return _fuse_new_317(args, op, op_size, version, user_data);
+}
+
+/* ABI compat version */
+struct fuse *fuse_new_31(struct fuse_args *args, const struct fuse_operations *op,
+			 size_t op_size, void *user_data);
+FUSE_SYMVER("fuse_new_31", "fuse_new@FUSE_3.1")
+struct fuse *fuse_new_31(struct fuse_args *args,
+			 const struct fuse_operations *op,
+			 size_t op_size, void *user_data)
+{
+		/* unknown version */
+	struct libfuse_version version = { 0 };
+
+	return _fuse_new_317(args, op, op_size, &version, user_data);
+}
+
+/*
+ * ABI compat version
+ * Emulates 3.0-style fuse_new(), which processes --help
+ */
 struct fuse *fuse_new_30(struct fuse_args *args, const struct fuse_operations *op,
-			 size_t op_size, void *private_data);
+			 size_t op_size, void *user_data);
 FUSE_SYMVER("fuse_new_30", "fuse_new@FUSE_3.0")
 struct fuse *fuse_new_30(struct fuse_args *args,
 			 const struct fuse_operations *op,
 			 size_t op_size, void *user_data)
 {
-	struct fuse_config conf;
-
-	memset(&conf, 0, sizeof(conf));
+	struct fuse_config conf = {0};
 
 	const struct fuse_opt opts[] = {
 		FUSE_LIB_OPT("-h", show_help, 1),
@@ -5069,6 +5123,7 @@ struct fuse *fuse_new_30(struct fuse_args *args,
 		return fuse_new_31(args, op, op_size, user_data);
 }
 
+
 void fuse_destroy(struct fuse *f)
 {
 	size_t i;