libusbgx: common: Add alloc_inst() and free_inst() callbacks

Those callback can be used by specific function type to allocate
and then free more memory than in raw usbg_function structure.

Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>

include/usbg/usbg_internal.h

@@ -46,6 +46,14 @@ struct usbg_function_type
 	/* Name of this function type */
 	char *name;
 
+	/* Called to allocate instance of function */
+	int (*alloc_inst)(struct usbg_function_type *, usbg_function_type,
+			  const char *, const char *, usbg_gadget *,
+			  struct usbg_function **);
+
+	/* Called to free memory used by function */
+	void (*free_inst)(struct usbg_function_type *, struct usbg_function *);
+
 	/*
 	 * Called when user would like to remove this function.
 	 * If this callback is provided it will be always called
@@ -252,6 +260,55 @@ int usbg_check_dir(const char *path);
 #define usbg_config_is_string(node) \
 	(config_setting_type(node) == CONFIG_TYPE_STRING)
 
+int usbg_init_function(struct usbg_function *f,
+		       struct usbg_function_type *ops,
+		       usbg_function_type type,
+		       const char *type_name,
+		       const char *instance,
+		       const char *path,
+		       struct usbg_gadget *parent);
+
+int usbg_cleanup_function(struct usbg_function *f);
+
+#define GENERIC_ALLOC_INST(prefix, _type, _member)			\
+	static int prefix##_alloc_inst(struct usbg_function_type *type, \
+				       usbg_function_type type_code,	\
+				       const char *instance, const char *path, \
+				       struct usbg_gadget *parent,	\
+				       struct usbg_function **f)	\
+	{								\
+		_type *ff;						\
+		int ret;						\
+									\
+		ff = malloc(sizeof(*ff));				\
+		if (!ff)						\
+			return USBG_ERROR_NO_MEM;			\
+									\
+		ret = usbg_init_function(&ff->_member, type, type_code,	\
+					 type->name, instance, path, parent); \
+		if (ret != USBG_SUCCESS)				\
+			goto free_func;					\
+									\
+		*f = &ff->_member;					\
+									\
+		return ret;						\
+									\
+	free_func:							\
+		free(ff);						\
+	out:								\
+		return ret;						\
+	}
+
+#define GENERIC_FREE_INST(prefix, _type, _member)			\
+	static void prefix##_free_inst(struct usbg_function_type *type,	\
+				       struct usbg_function *f)		\
+	{								\
+		_type *ff = container_of(f, _type, _member);		\
+									\
+		usbg_cleanup_function(&ff->_member);			\
+		free(ff);						\
+	}
+
 typedef int (*usbg_attr_get_func)(const char *, const char *, const char *, void *);
 typedef int (*usbg_attr_set_func)(const char *, const char *, const char *, void *);
 

src/function/ether.c

@@ -18,6 +18,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_ether {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(ether, struct usbg_f_ether, func);
+
+GENERIC_FREE_INST(ether, struct usbg_f_ether, func);
+
 static int ether_set_attrs(struct usbg_function *f,
 			   const usbg_function_attrs *f_attrs)
 {
@@ -216,6 +224,8 @@ out:
 #endif /* HAS_LIBCONFIG */
 
 #define ETHER_FUNCTION_OPTS			\
+	.alloc_inst = ether_alloc_inst,		\
+	.free_inst = ether_free_inst,		\
 	.set_attrs = ether_set_attrs,		\
 	.get_attrs = ether_get_attrs,		\
 	.cleanup_attrs = ether_cleanup_attrs,	\

src/function/ffs.c

@@ -17,6 +17,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_fs {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(ffs, struct usbg_f_fs, func);
+
+GENERIC_FREE_INST(ffs, struct usbg_f_fs, func);
+
 static int ffs_set_attrs(struct usbg_function *f,
 			 const usbg_function_attrs *f_attrs)
 {
@@ -72,6 +80,8 @@ static int ffs_libconfig_export(struct usbg_function *f,
 
 struct usbg_function_type usbg_f_type_ffs = {
 	.name = "ffs",
+	.alloc_inst = ffs_alloc_inst,
+	.free_inst = ffs_free_inst,
 	.set_attrs = ffs_set_attrs,
 	.get_attrs = ffs_get_attrs,
 	.cleanup_attrs = ffs_cleanup_attrs,

src/function/loopback.c

@@ -17,6 +17,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_loopback {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(loopback, struct usbg_f_loopback, func);
+
+GENERIC_FREE_INST(loopback, struct usbg_f_loopback, func);
+
 static int loopback_set_attrs(struct usbg_function *f,
 			    const usbg_function_attrs *f_attrs)
 {
@@ -141,6 +149,8 @@ out:
 
 struct usbg_function_type usbg_f_type_loopback = {
 	.name = "loopback",
+	.alloc_inst = loopback_alloc_inst,
+	.free_inst = loopback_free_inst,
 	.set_attrs = loopback_set_attrs,
 	.get_attrs = loopback_get_attrs,
 #ifdef HAS_LIBCONFIG

src/function/midi.c

@@ -18,6 +18,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_midi {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(midi, struct usbg_f_midi, func);
+
+GENERIC_FREE_INST(midi, struct usbg_f_midi, func);
+
 static int midi_set_attrs(struct usbg_function *f,
 			  const usbg_function_attrs *f_attrs)
 {
@@ -216,6 +224,8 @@ out:
 
 struct usbg_function_type usbg_f_type_midi = {
 	.name = "midi",
+	.alloc_inst = midi_alloc_inst,
+	.free_inst = midi_free_inst,
 	.set_attrs = midi_set_attrs,
 	.get_attrs = midi_get_attrs,
 	.cleanup_attrs = midi_cleanup_attrs,

src/function/ms.c

@@ -21,6 +21,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_ms {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(ms, struct usbg_f_ms, func);
+
+GENERIC_FREE_INST(ms, struct usbg_f_ms, func);
+
 static inline int lun_select(const struct dirent *dent)
 {
 	int ret;
@@ -652,6 +660,8 @@ out:
 
 struct usbg_function_type usbg_f_type_ms = {
 	.name = "mass_storage",
+	.alloc_inst = ms_alloc_inst,
+	.free_inst = ms_free_inst,
 	.set_attrs = ms_set_attrs,
 	.get_attrs = ms_get_attrs,
 	.cleanup_attrs = ms_cleanup_attrs,

src/function/phonet.c

@@ -18,6 +18,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_phonet {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(phonet, struct usbg_f_phonet, func);
+
+GENERIC_FREE_INST(phonet, struct usbg_f_phonet, func);
+
 static int phonet_set_attrs(struct usbg_function *f,
 			    const usbg_function_attrs *f_attrs)
 {
@@ -71,6 +79,8 @@ static int phonet_libconfig_export(struct usbg_function *f,
 
 struct usbg_function_type usbg_f_type_phonet = {
 	.name = "phonet",
+	.alloc_inst = phonet_alloc_inst,
+	.free_inst = phonet_free_inst,
 	.set_attrs = phonet_set_attrs,
 	.get_attrs = phonet_get_attrs,
 	.cleanup_attrs = phonet_cleanup_attrs,

src/function/serial.c

@@ -17,6 +17,14 @@
 #include <libconfig.h>
 #endif
 
+struct usbg_f_serial {
+	struct usbg_function func;
+};
+
+GENERIC_ALLOC_INST(serial, struct usbg_f_serial, func);
+
+GENERIC_FREE_INST(serial, struct usbg_f_serial, func);
+
 static int serial_set_attrs(struct usbg_function *f,
 			    const usbg_function_attrs *f_attrs)
 {
@@ -92,8 +100,10 @@ static int serial_libconfig_import(struct usbg_function *f,
 
 /* We don' import port_num as it is read only */
 #define SERIAL_FUNCTION_OPTS			\
-	.set_attrs = serial_set_attrs,		\
-	.get_attrs = serial_get_attrs,		\
+	.alloc_inst = serial_alloc_inst,	\
+	.free_inst = serial_free_inst,	        \
+	.set_attrs = serial_set_attrs,	        \
+	.get_attrs = serial_get_attrs,	        \
 	SERIAL_LIBCONFIG_DEP_OPS,	        \
 	.import = serial_libconfig_import
 

src/usbg.c

@@ -284,10 +284,8 @@ static inline void usbg_free_binding(usbg_binding *b)
 
 static inline void usbg_free_function(usbg_function *f)
 {
-	free(f->path);
-	free(f->name);
-	free(f->label);
-	free(f);
+	if (f->ops->free_inst)
+		f->ops->free_inst(f->ops, f);
 }
 
 static void usbg_free_config(usbg_config *c)
@@ -426,46 +424,16 @@ out:
 	return c;
 }
 
-static usbg_function *usbg_allocate_function(const char *path,
-		usbg_function_type type, const char *instance, usbg_gadget *parent)
+static usbg_function *
+usbg_allocate_function(const char *path, usbg_function_type type,
+		       const char *instance, usbg_gadget *parent)
 {
 	usbg_function *f;
-	const char *type_name;
 	int ret;
 
-	f = malloc(sizeof(*f));
-	if (!f)
-		goto out;
-
-	f->label = NULL;
-	type_name = usbg_get_function_type_str(type);
-	if (!type_name) {
-		free(f);
-		f = NULL;
-		goto out;
-	}
-
-	ret = asprintf(&(f->name), "%s.%s", type_name, instance);
-	if (ret < 0) {
-		free(f);
-		f = NULL;
-		goto out;
-	}
-	f->instance = f->name + strlen(type_name) + 1;
-	f->path = strdup(path);
-	f->parent = parent;
-	f->type = type;
-	f->ops = function_types[type];
-
-	if (!(f->path)) {
-		free(f->name);
-		free(f->path);
-		free(f);
-		f = NULL;
-	}
-
-out:
-	return f;
+	ret = function_types[type]->alloc_inst(function_types[type], type,
+					       instance, path, parent, &f);
+	return ret == 0 ? f : NULL;
 }
 
 static usbg_binding *usbg_allocate_binding(const char *path, const char *name,

src/usbg_common.c

@@ -265,7 +265,30 @@ int usbg_check_dir(const char *path)
 	return ret;
 }
 
+int usbg_init_function(struct usbg_function *f,
+		       struct usbg_function_type *ops,
+		       usbg_function_type type,
+		       const char *type_name,
+		       const char *instance,
+		       const char *path,
+		       struct usbg_gadget *parent)
+{
+	int ret;
 
+	ret = asprintf(&(f->name), "%s.%s", type_name, instance);
+	if (ret < 0)
+		return USBG_ERROR_NO_MEM;
+
+	f->instance = f->name + strlen(type_name) + 1;
+	f->path = strdup(path);
+	f->parent = parent;
+	f->type = type;
+	f->ops = ops;
+	f->label = NULL;
+	memset(&f->fnode, 0, sizeof(f->fnode));
+
+	return 0;
+}
 
 int usbg_get_ether_addr(const char *path, const char *name,
 			      const char *attr, void *val)
@@ -423,3 +446,9 @@ int usbg_set_config_node_ether_addr(config_setting_t *root,
 	return usbg_set_config_node_string(root, node_name, &ptr);
 }
 
+int usbg_cleanup_function(struct usbg_function *f)
+{
+	free(f->path);
+	free(f->name);
+	free(f->label);
+}