[babeltrace.git] / plugins / component-factory.c

/*
 * component-factory.c
 *
 * Babeltrace Plugin Component Factory
 *
 * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <babeltrace/plugin/component-factory.h>
#include <babeltrace/plugin/component-factory-internal.h>
#include <babeltrace/babeltrace-internal.h>
#include <babeltrace/compiler.h>
#include <babeltrace/ref.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <gmodule.h>

#define NATIVE_PLUGIN_SUFFIX ".so"
#define NATIVE_PLUGIN_SUFFIX_LEN sizeof(NATIVE_PLUGIN_SUFFIX)
#define LIBTOOL_PLUGIN_SUFFIX ".la"
#define LIBTOOL_PLUGIN_SUFFIX_LEN sizeof(LIBTOOL_PLUGIN_SUFFIX)
#define PLUGIN_SUFFIX_LEN max_t(size_t, sizeof(NATIVE_PLUGIN_SUFFIX), \
		sizeof(LIBTOOL_PLUGIN_SUFFIX))

/* Allocate dirent as recommended by READDIR(3), NOTES on readdir_r */
static
struct dirent *alloc_dirent(const char *path)
{
	size_t len;
	long name_max;
	struct dirent *entry;

	name_max = pathconf(path, _PC_NAME_MAX);
	if (name_max == -1) {
		name_max = PATH_MAX;
	}
	len = offsetof(struct dirent, d_name) + name_max + 1;
	entry = zmalloc(len);
	return entry;
}

static
enum bt_component_factory_status
bt_component_factory_load_file(struct bt_component_factory *factory,
		const char *path)
{
	enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK;
	enum bt_component_status component_status;
	size_t path_len;
	GModule *module;
	struct bt_plugin *plugin;

	if (!factory || !path) {
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
		goto end;
	}

	path_len = strlen(path);
	if (path_len <= PLUGIN_SUFFIX_LEN) {
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
		goto end;
	}

	path_len++;
	/*
	 * Check if the file ends with a known plugin file type suffix (i.e. .so
	 * or .la on Linux).
	 */
	if (strncmp(NATIVE_PLUGIN_SUFFIX,
			path + path_len - NATIVE_PLUGIN_SUFFIX_LEN,
			NATIVE_PLUGIN_SUFFIX_LEN) &&
			strncmp(LIBTOOL_PLUGIN_SUFFIX,
			path + path_len - LIBTOOL_PLUGIN_SUFFIX_LEN,
			LIBTOOL_PLUGIN_SUFFIX_LEN)) {
		/* Name indicates that this is not a plugin file. */
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
		goto end;
	}

	module = g_module_open(path, 0);
	if (!module) {
		printf_error("Module open error: %s", g_module_error());
		ret = BT_COMPONENT_FACTORY_STATUS_ERROR;
		goto end;
	}

	/* Load plugin and make sure it defines the required entry points */
	plugin = bt_plugin_create(module);
	if (!plugin) {
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL_PLUGIN;
		if (!g_module_close(module)) {
			printf_error("Module close error: %s",
				g_module_error());
		}
		goto end;
	}

	component_status = bt_plugin_register_component_classes(plugin,
			factory);
	if (component_status != BT_COMPONENT_STATUS_OK) {
		switch (component_status) {
		case BT_COMPONENT_STATUS_NOMEM:
			ret = BT_COMPONENT_FACTORY_STATUS_NOMEM;
			break;
		default:
			ret = BT_COMPONENT_FACTORY_STATUS_ERROR;
			break;
		}

		BT_PUT(plugin);
		goto end;
	}
	g_ptr_array_add(factory->plugins, plugin);
end:
	return ret;
}

static
enum bt_component_factory_status
bt_component_factory_load_dir_recursive(struct bt_component_factory *factory,
		const char *path)
{
	DIR *directory = NULL;
	struct dirent *entry = NULL, *result = NULL;
	char *file_path = NULL;
	size_t path_len = strlen(path);
	enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK;

	if (path_len >= PATH_MAX) {
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
		goto end;
	}

	entry = alloc_dirent(path);
	if (!entry) {
		ret = BT_COMPONENT_FACTORY_STATUS_NOMEM;
		goto end;
	}

	file_path = zmalloc(PATH_MAX);
	if (!file_path) {
		ret = BT_COMPONENT_FACTORY_STATUS_NOMEM;
		goto end;
	}

	strncpy(file_path, path, path_len);
	/* Append a trailing '/' to the path */
	if (file_path[path_len - 1] != '/') {
		file_path[path_len++] = '/';
	}

	directory = opendir(file_path);
	if (!directory) {
		perror("Failed to open plug-in directory");
		ret = BT_COMPONENT_FACTORY_STATUS_ERROR;
		goto end;
	}

	/* Recursively walk directory */
	while (!readdir_r(directory, entry, &result) && result) {
		struct stat st;
		int stat_ret;
		size_t file_name_len;

		if (result->d_name[0] == '.') {
			/* Skip hidden files, . and .. */
			continue;
		}

		file_name_len = strlen(result->d_name);

		if (path_len + file_name_len >= PATH_MAX) {
			continue;
		}

		strncpy(file_path + path_len, result->d_name, file_name_len);
		file_path[path_len + file_name_len] = '\0';

		stat_ret = stat(file_path, &st);
		if (stat_ret < 0) {
			/* Continue to next file / directory. */
			printf_perror("Failed to stat() plugin file");
			continue;
		}

		if (S_ISDIR(st.st_mode)) {
			ret = bt_component_factory_load_dir_recursive(factory,
					file_path);
			if (ret != BT_COMPONENT_FACTORY_STATUS_OK) {
				goto end;
			}
		} else if (S_ISREG(st.st_mode)) {
		        bt_component_factory_load_file(factory, file_path);
		}
	}
end:
	if (directory) {
		if (closedir(directory)) {
			/*
			 * We don't want to override the error since there is
			 * nothing could do.
			 */
		        perror("Failed to close plug-in directory");
		}
	}
	free(entry);
	free(file_path);
	return ret;
}

static
void bt_component_factory_destroy(struct bt_object *obj)
{
	struct bt_component_factory *factory = NULL;

	assert(obj);
	factory = container_of(obj, struct bt_component_factory, base);

	if (factory->plugins) {
		g_ptr_array_free(factory->plugins, TRUE);
	}
	if (factory->components) {
		g_ptr_array_free(factory->components, TRUE);
	}
	g_free(factory);
}

struct bt_component_factory *bt_component_factory_create(void)
{
	struct bt_component_factory *factory;

	factory = g_new0(struct bt_component_factory, 1);
	if (!factory) {
		goto end;
	}

	bt_object_init(factory, bt_component_factory_destroy);
	factory->plugins = g_ptr_array_new_with_free_func(
		(GDestroyNotify) bt_put);
	if (!factory->plugins) {
		goto error;
	}
	factory->components = g_ptr_array_new_with_free_func(
		(GDestroyNotify) bt_put);
	if (!factory->components) {
		goto error;
	}
end:
	return factory;
error:
        BT_PUT(factory);
	return factory;
}

enum bt_component_factory_status bt_component_factory_load(
		struct bt_component_factory *factory, const char *path)
{
	enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK;

	if (!factory || !path) {
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
		goto end;
	}

	if (!g_file_test(path, G_FILE_TEST_EXISTS)) {
		ret = BT_COMPONENT_FACTORY_STATUS_NOENT;
		goto end;
	}

	if (g_file_test(path, G_FILE_TEST_IS_DIR)) {
		ret = bt_component_factory_load_dir_recursive(factory, path);
	} else if (g_file_test(path, G_FILE_TEST_IS_REGULAR) ||
			g_file_test(path, G_FILE_TEST_IS_SYMLINK)) {
		ret = bt_component_factory_load_file(factory, path);
	} else {
		ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
		goto end;
	}
end:
	return ret;
}
Commit	Line	Data
f3e4505b JG	1	/*
	2	* component-factory.c
	3	*
	4	* Babeltrace Plugin Component Factory
	5	*
	6	* Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
	7	*
	8	* Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
	9	*
	10	* Permission is hereby granted, free of charge, to any person obtaining a copy
	11	* of this software and associated documentation files (the "Software"), to deal
	12	* in the Software without restriction, including without limitation the rights
	13	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	14	* copies of the Software, and to permit persons to whom the Software is
	15	* furnished to do so, subject to the following conditions:
	16	*
	17	* The above copyright notice and this permission notice shall be included in
	18	* all copies or substantial portions of the Software.
	19	*
	20	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	21	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	23	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	24	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	25	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	26	* SOFTWARE.
	27	*/
	28
	29	#include <babeltrace/plugin/component-factory.h>
	30	#include <babeltrace/plugin/component-factory-internal.h>
	31	#include <babeltrace/babeltrace-internal.h>
	32	#include <babeltrace/compiler.h>
b8a06801	33	#include <babeltrace/ref.h>
f3e4505b JG	34	#include <unistd.h>
	35	#include <stdlib.h>
	36	#include <sys/stat.h>
fb2dcc52	37	#include <gmodule.h>
f3e4505b JG	38
	39	#define NATIVE_PLUGIN_SUFFIX ".so"
	40	#define NATIVE_PLUGIN_SUFFIX_LEN sizeof(NATIVE_PLUGIN_SUFFIX)
	41	#define LIBTOOL_PLUGIN_SUFFIX ".la"
	42	#define LIBTOOL_PLUGIN_SUFFIX_LEN sizeof(LIBTOOL_PLUGIN_SUFFIX)
73299554 JG	43	#define PLUGIN_SUFFIX_LEN max_t(size_t, sizeof(NATIVE_PLUGIN_SUFFIX), \
73299554 JG	44	sizeof(LIBTOOL_PLUGIN_SUFFIX))
f3e4505b	45
f3e4505b JG	46	/* Allocate dirent as recommended by READDIR(3), NOTES on readdir_r */
	47	static
	48	struct dirent alloc_dirent(const char path)
	49	{
	50	size_t len;
	51	long name_max;
	52	struct dirent *entry;
	53
	54	name_max = pathconf(path, _PC_NAME_MAX);
	55	if (name_max == -1) {
	56	name_max = PATH_MAX;
	57	}
	58	len = offsetof(struct dirent, d_name) + name_max + 1;
	59	entry = zmalloc(len);
	60	return entry;
	61	}
	62
	63	static
	64	enum bt_component_factory_status
	65	bt_component_factory_load_file(struct bt_component_factory *factory,
	66	const char *path)
	67	{
	68	enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK;
fb2dcc52	69	enum bt_component_status component_status;
f3e4505b JG	70	size_t path_len;
f3e4505b JG	71	GModule *module;
fb2dcc52	72	struct bt_plugin *plugin;
f3e4505b JG	73
	74	if (!factory \|\| !path) {
	75	ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
	76	goto end;
	77	}
	78
	79	path_len = strlen(path);
	80	if (path_len <= PLUGIN_SUFFIX_LEN) {
73299554	81	ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
f3e4505b JG	82	goto end;
	83	}
	84
	85	path_len++;
	86	/*
	87	* Check if the file ends with a known plugin file type suffix (i.e. .so
	88	* or .la on Linux).
	89	*/
	90	if (strncmp(NATIVE_PLUGIN_SUFFIX,
b8a06801 JG	91	path + path_len - NATIVE_PLUGIN_SUFFIX_LEN,
	92	NATIVE_PLUGIN_SUFFIX_LEN) &&
	93	strncmp(LIBTOOL_PLUGIN_SUFFIX,
	94	path + path_len - LIBTOOL_PLUGIN_SUFFIX_LEN,
	95	LIBTOOL_PLUGIN_SUFFIX_LEN)) {
73299554 JG	96	/* Name indicates that this is not a plugin file. */
73299554 JG	97	ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
f3e4505b JG	98	goto end;
	99	}
	100
	101	module = g_module_open(path, 0);
	102	if (!module) {
	103	printf_error("Module open error: %s", g_module_error());
73299554	104	ret = BT_COMPONENT_FACTORY_STATUS_ERROR;
f3e4505b JG	105	goto end;
	106	}
	107
fb2dcc52 JG	108	/* Load plugin and make sure it defines the required entry points */
fb2dcc52 JG	109	plugin = bt_plugin_create(module);
73299554	110	if (!plugin) {
fb2dcc52	111	ret = BT_COMPONENT_FACTORY_STATUS_INVAL_PLUGIN;
73299554 JG	112	if (!g_module_close(module)) {
73299554 JG	113	printf_error("Module close error: %s",
fb2dcc52 JG	114	g_module_error());
	115	}
	116	goto end;
	117	}
	118
	119	component_status = bt_plugin_register_component_classes(plugin,
b8a06801	120	factory);
fb2dcc52 JG	121	if (component_status != BT_COMPONENT_STATUS_OK) {
	122	switch (component_status) {
	123	case BT_COMPONENT_STATUS_NOMEM:
	124	ret = BT_COMPONENT_FACTORY_STATUS_NOMEM;
	125	break;
	126	default:
	127	ret = BT_COMPONENT_FACTORY_STATUS_ERROR;
	128	break;
73299554	129	}
b8a06801 JG	130
b8a06801 JG	131	BT_PUT(plugin);
73299554 JG	132	goto end;
73299554 JG	133	}
fb2dcc52	134	g_ptr_array_add(factory->plugins, plugin);
f3e4505b JG	135	end:
	136	return ret;
	137	}
	138
	139	static
	140	enum bt_component_factory_status
	141	bt_component_factory_load_dir_recursive(struct bt_component_factory *factory,
	142	const char *path)
	143	{
	144	DIR *directory = NULL;
	145	struct dirent entry = NULL, result = NULL;
	146	char *file_path = NULL;
	147	size_t path_len = strlen(path);
	148	enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK;
	149
	150	if (path_len >= PATH_MAX) {
	151	ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
	152	goto end;
	153	}
	154
	155	entry = alloc_dirent(path);
	156	if (!entry) {
	157	ret = BT_COMPONENT_FACTORY_STATUS_NOMEM;
	158	goto end;
	159	}
	160
	161	file_path = zmalloc(PATH_MAX);
	162	if (!file_path) {
	163	ret = BT_COMPONENT_FACTORY_STATUS_NOMEM;
	164	goto end;
	165	}
	166
	167	strncpy(file_path, path, path_len);
	168	/* Append a trailing '/' to the path */
	169	if (file_path[path_len - 1] != '/') {
	170	file_path[path_len++] = '/';
	171	}
	172
33bceaf8 JG	173	directory = opendir(file_path);
	174	if (!directory) {
	175	perror("Failed to open plug-in directory");
	176	ret = BT_COMPONENT_FACTORY_STATUS_ERROR;
	177	goto end;
	178	}
	179
f3e4505b JG	180	/* Recursively walk directory */
	181	while (!readdir_r(directory, entry, &result) && result) {
	182	struct stat st;
	183	int stat_ret;
33bceaf8 JG	184	size_t file_name_len;
	185
	186	if (result->d_name[0] == '.') {
	187	/* Skip hidden files, . and .. */
	188	continue;
	189	}
	190
	191	file_name_len = strlen(result->d_name);
f3e4505b JG	192
	193	if (path_len + file_name_len >= PATH_MAX) {
	194	continue;
	195	}
	196
	197	strncpy(file_path + path_len, result->d_name, file_name_len);
	198	file_path[path_len + file_name_len] = '\0';
	199
	200	stat_ret = stat(file_path, &st);
	201	if (stat_ret < 0) {
	202	/* Continue to next file / directory. */
	203	printf_perror("Failed to stat() plugin file");
	204	continue;
	205	}
	206
	207	if (S_ISDIR(st.st_mode)) {
	208	ret = bt_component_factory_load_dir_recursive(factory,
b8a06801	209	file_path);
f3e4505b JG	210	if (ret != BT_COMPONENT_FACTORY_STATUS_OK) {
	211	goto end;
	212	}
	213	} else if (S_ISREG(st.st_mode)) {
73299554	214	bt_component_factory_load_file(factory, file_path);
f3e4505b JG	215	}
	216	}
	217	end:
33bceaf8 JG	218	if (directory) {
	219	if (closedir(directory)) {
	220	/*
	221	* We don't want to override the error since there is
	222	* nothing could do.
	223	*/
	224	perror("Failed to close plug-in directory");
	225	}
	226	}
f3e4505b JG	227	free(entry);
	228	free(file_path);
	229	return ret;
	230	}
	231
b8a06801 JG	232	static
b8a06801 JG	233	void bt_component_factory_destroy(struct bt_object *obj)
f3e4505b	234	{
b8a06801 JG	235	struct bt_component_factory *factory = NULL;
	236
	237	assert(obj);
	238	factory = container_of(obj, struct bt_component_factory, base);
f3e4505b	239
fb2dcc52 JG	240	if (factory->plugins) {
	241	g_ptr_array_free(factory->plugins, TRUE);
	242	}
	243	if (factory->components) {
	244	g_ptr_array_free(factory->components, TRUE);
	245	}
f3e4505b JG	246	g_free(factory);
	247	}
	248
b8a06801	249	struct bt_component_factory *bt_component_factory_create(void)
f3e4505b JG	250	{
	251	struct bt_component_factory *factory;
	252
	253	factory = g_new0(struct bt_component_factory, 1);
	254	if (!factory) {
	255	goto end;
	256	}
	257
b8a06801	258	bt_object_init(factory, bt_component_factory_destroy);
fb2dcc52	259	factory->plugins = g_ptr_array_new_with_free_func(
b8a06801	260	(GDestroyNotify) bt_put);
73299554	261	if (!factory->plugins) {
f3e4505b JG	262	goto error;
f3e4505b JG	263	}
fb2dcc52	264	factory->components = g_ptr_array_new_with_free_func(
b8a06801	265	(GDestroyNotify) bt_put);
fb2dcc52 JG	266	if (!factory->components) {
	267	goto error;
	268	}
f3e4505b JG	269	end:
	270	return factory;
	271	error:
b8a06801 JG	272	BT_PUT(factory);
b8a06801 JG	273	return factory;
f3e4505b JG	274	}
	275
	276	enum bt_component_factory_status bt_component_factory_load(
	277	struct bt_component_factory factory, const char path)
	278	{
	279	enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK;
f3e4505b JG	280
	281	if (!factory \|\| !path) {
	282	ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
	283	goto end;
	284	}
	285
b8a06801 JG	286	if (!g_file_test(path, G_FILE_TEST_EXISTS)) {
	287	ret = BT_COMPONENT_FACTORY_STATUS_NOENT;
	288	goto end;
f3e4505b JG	289	}
f3e4505b JG	290
b8a06801	291	if (g_file_test(path, G_FILE_TEST_IS_DIR)) {
f3e4505b	292	ret = bt_component_factory_load_dir_recursive(factory, path);
b8a06801 JG	293	} else if (g_file_test(path, G_FILE_TEST_IS_REGULAR) \|\|
b8a06801 JG	294	g_file_test(path, G_FILE_TEST_IS_SYMLINK)) {
f3e4505b	295	ret = bt_component_factory_load_file(factory, path);
b8a06801 JG	296	} else {
	297	ret = BT_COMPONENT_FACTORY_STATUS_INVAL;
	298	goto end;
f3e4505b JG	299	}
f3e4505b JG	300	end:
f3e4505b JG	301	return ret;
f3e4505b JG	302	}