[lttng-tools.git] / src / bin / lttng / uprobe.cpp

/*
 * Copyright (C) 2020 EfficiOS, Inc.
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#include "uprobe.hpp"

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#include "common/compat/getenv.hpp"
#include "common/string-utils/string-utils.hpp"
#include "common/utils.hpp"
#include "common/path.hpp"
#include "lttng/constant.h"

#include "command.hpp"

/*
 * Walk the directories in the PATH environment variable to find the target
 * binary passed as parameter.
 *
 * On success, the full path of the binary is copied in binary_full_path out
 * parameter. This buffer is allocated by the caller and must be at least
 * LTTNG_PATH_MAX bytes long.
 * On failure, returns -1;
 */
static
int walk_command_search_path(const char *binary, char *binary_full_path)
{
	char *tentative_binary_path = NULL;
	char *command_search_path = NULL;
	char *curr_search_dir_end = NULL;
	char *curr_search_dir = NULL;
	struct stat stat_output;
	int ret = 0;

	command_search_path = lttng_secure_getenv("PATH");
	if (!command_search_path) {
		ret = -1;
		goto end;
	}

	/*
	 * Duplicate the $PATH string as the char pointer returned by getenv() should
	 * not be modified.
	 */
	command_search_path = strdup(command_search_path);
	if (!command_search_path) {
		ret = -1;
		goto end;
	}

	/*
	 * This char array is used to concatenate path to binary to look for
	 * the binary.
	 */
	tentative_binary_path = calloc<char>(LTTNG_PATH_MAX);
	if (!tentative_binary_path) {
		ret = -1;
		goto alloc_error;
	}

	curr_search_dir = command_search_path;
	do {
		/*
		 * Split on ':'. The return value of this call points to the
		 * matching character.
		 */
		curr_search_dir_end = strchr(curr_search_dir, ':');
		if (curr_search_dir_end != NULL) {
			/*
			 * Add a NULL byte to the end of the first token so it
			 * can be used as a string.
			 */
			curr_search_dir_end[0] = '\0';
		}

		/* Empty the tentative path */
		memset(tentative_binary_path, 0, LTTNG_PATH_MAX * sizeof(char));

		/*
		 * Build the tentative path to the binary using the current
		 * search directory and the name of the binary.
		 */
		ret = snprintf(tentative_binary_path, LTTNG_PATH_MAX, "%s/%s",
				curr_search_dir, binary);
		if (ret < 0) {
			goto free_binary_path;
		}
		if (ret < LTTNG_PATH_MAX) {
			 /*
			  * Use STAT(2) to see if the file exists.
			 */
			ret = stat(tentative_binary_path, &stat_output);
			if (ret == 0) {
				/*
				 * Verify that it is a regular file or a
				 * symlink and not a special file (e.g.
				 * device).
				 */
				if (S_ISREG(stat_output.st_mode)
						|| S_ISLNK(stat_output.st_mode)) {
					/*
					 * Found a match, set the out parameter
					 * and return success.
					 */
					ret = lttng_strncpy(binary_full_path,
							tentative_binary_path,
							LTTNG_PATH_MAX);
					if (ret == -1) {
						ERR("Source path does not fit "
							"in destination buffer.");
					}
					goto free_binary_path;
				}
			}
		}
		/* Go to the next entry in the $PATH variable. */
		curr_search_dir = curr_search_dir_end + 1;
	} while (curr_search_dir_end != NULL);

free_binary_path:
	free(tentative_binary_path);
alloc_error:
	free(command_search_path);
end:
	return ret;
}

/*
 * Check if the symbol field passed by the user is in fact an address or an
 * offset from a symbol. Those two instrumentation types are not supported yet.
 * It's expected to be a common mistake because of the existing --probe option
 * that does support these formats.
 *
 * Here are examples of these unsupported formats for the --userspace-probe
 * option:
 * elf:/path/to/binary:0x400430
 * elf:/path/to/binary:4194364
 * elf:/path/to/binary:my_symbol+0x323
 * elf:/path/to/binary:my_symbol+43
 */
static
int warn_userspace_probe_syntax(const char *symbol)
{
	int ret;

	/* Check if the symbol field is an hex address. */
	ret = sscanf(symbol, "0x%*x");
	if (ret > 0) {
		/* If there is a match, print a warning and return an error. */
		ERR("Userspace probe on address not supported yet.");
		ret = CMD_UNSUPPORTED;
		goto error;
	}

	/* Check if the symbol field is an decimal address. */
	ret = sscanf(symbol, "%*u");
	if (ret > 0) {
		/* If there is a match, print a warning and return an error. */
		ERR("Userspace probe on address not supported yet.");
		ret = CMD_UNSUPPORTED;
		goto error;
	}

	/* Check if the symbol field is symbol+hex_offset. */
	ret = sscanf(symbol, "%*[^+]+0x%*x");
	if (ret > 0) {
		/* If there is a match, print a warning and return an error. */
		ERR("Userspace probe on symbol+offset not supported yet.");
		ret = CMD_UNSUPPORTED;
		goto error;
	}

	/* Check if the symbol field is symbol+decimal_offset. */
	ret = sscanf(symbol, "%*[^+]+%*u");
	if (ret > 0) {
		/* If there is a match, print a warning and return an error. */
		ERR("Userspace probe on symbol+offset not supported yet.");
		ret = CMD_UNSUPPORTED;
		goto error;
	}

	ret = 0;

error:
	return ret;
}

/*
 * Parse userspace probe options
 * Set the userspace probe fields in the lttng_event struct and set the
 * target_path to the path to the binary.
 */
int parse_userspace_probe_opts(const char *opt,
		struct lttng_userspace_probe_location **probe_location)
{
	int ret = CMD_SUCCESS;
	size_t num_token = 0;
	char *target_path = NULL;
	char *unescaped_target_path = NULL;
	char *real_target_path = NULL;
	char *symbol_name = NULL, *probe_name = NULL, *provider_name = NULL;
	struct lttng_userspace_probe_location *probe_location_local = NULL;
	struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
	struct lttng_dynamic_pointer_array tokens;

	LTTNG_ASSERT(opt);

	/*
	 * userspace probe fields are separated by ':'.
	 */
	ret = strutils_split(opt, ':', true, &tokens);
	if (ret == 0) {
		num_token = lttng_dynamic_pointer_array_get_count(&tokens);
	}

	/*
	 * Early sanity check that the number of parameter is between 2 and 4
	 * inclusively.
	 * elf:PATH:SYMBOL
	 * std:PATH:PROVIDER_NAME:PROBE_NAME
	 * PATH:SYMBOL (same behavior as ELF)
	 */
	if (ret < 0 || num_token < 2 || num_token > 4) {
		ret = CMD_ERROR;
		goto end;
	}

	/*
	 * Looking up the first parameter will tell the technique to use to
	 * interpret the userspace probe/function description.
	 */
	switch (num_token) {
	case 2:
		/* When the probe type is omitted we assume ELF for now. */
	case 3:
		if (num_token == 3 && strcmp((const char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 0), "elf") == 0) {
			target_path = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 1);
			symbol_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 2);
		} else if (num_token == 2) {
			target_path = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 0);
			symbol_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 1);
		} else {
			ret = CMD_ERROR;
			goto end;
		}
		lookup_method =
			lttng_userspace_probe_location_lookup_method_function_elf_create();
		if (!lookup_method) {
			WARN("Failed to create ELF lookup method");
			ret = CMD_ERROR;
			goto end;
		}
		break;
	case 4:
		if (strcmp((const char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 0), "sdt") == 0) {
			target_path = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 1);
			provider_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 2);
			probe_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 3);
		} else {
			ret = CMD_ERROR;
			goto end;
		}
		lookup_method =
			lttng_userspace_probe_location_lookup_method_tracepoint_sdt_create();
		if (!lookup_method) {
			WARN("Failed to create SDT lookup method");
			ret = CMD_ERROR;
			goto end;
		}
		break;
	default:
		ret = CMD_ERROR;
		goto end;
	}

	/* strutils_unescape_string allocates a new char *. */
	unescaped_target_path = strutils_unescape_string(target_path, 0);
	if (!unescaped_target_path) {
		ret = CMD_ERROR;
		goto end;
	}

	/*
	 * If there is not forward slash in the path. Walk the $PATH else
	 * expand.
	 */
	if (strchr(unescaped_target_path, '/') == NULL) {
		/* Walk the $PATH variable to find the targeted binary. */
		real_target_path = calloc<char>(LTTNG_PATH_MAX);
		if (!real_target_path) {
			PERROR("Error allocating path buffer");
			ret = CMD_ERROR;
			goto end;
		}
		ret = walk_command_search_path(unescaped_target_path, real_target_path);
		if (ret) {
			ERR("Binary not found.");
			ret = CMD_ERROR;
			goto end;
		}
	} else {
		/*
		 * Expand references to `/./` and `/../`. This function does not check
		 * if the file exists. This call returns an allocated buffer on
		 * success.
		 */
		real_target_path = utils_expand_path_keep_symlink(unescaped_target_path);
		if (!real_target_path) {
			ERR("Error expanding the path to binary.");
			ret = CMD_ERROR;
			goto end;
		}

		/*
		 * Check if the file exists using access(2), If it does not,
		 * return an error.
		 */
		ret = access(real_target_path, F_OK);
		if (ret) {
			ERR("Cannot find binary at path: %s.", real_target_path);
			ret = CMD_ERROR;
			goto end;
		}
	}

	switch (lttng_userspace_probe_location_lookup_method_get_type(lookup_method)) {
	case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
		/*
		 * Check for common mistakes in userspace probe description syntax.
		 */
		ret = warn_userspace_probe_syntax(symbol_name);
		if (ret) {
			goto end;
		}

		probe_location_local = lttng_userspace_probe_location_function_create(
				real_target_path, symbol_name, lookup_method);
		if (!probe_location_local) {
			WARN("Failed to create function probe location");
			ret = CMD_ERROR;
			goto end;
		}

		/* Ownership transferred to probe_location. */
		lookup_method = NULL;
		break;
	case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
		probe_location_local = lttng_userspace_probe_location_tracepoint_create(
				real_target_path, provider_name, probe_name, lookup_method);
		if (!probe_location_local) {
			WARN("Failed to create function probe location");
			ret = CMD_ERROR;
			goto end;
		}

		/* Ownership transferred to probe_location. */
		lookup_method = NULL;
		break;
	default:
		ret = CMD_ERROR;
		goto end;
	}

	/*
	 * Everything went fine, transfer ownership of probe location to
	 * caller.
	 */
	*probe_location = probe_location_local;
	probe_location_local = NULL;

end:
	lttng_userspace_probe_location_destroy(probe_location_local);
	lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
	lttng_dynamic_pointer_array_reset(&tokens);
	/*
	 * Freeing both char * here makes the error handling simplier. free()
	 * performs not action if the pointer is NULL.
	 */
	free(real_target_path);
	free(unescaped_target_path);

	return ret;
}
Commit	Line	Data
0c4e727b JR	1	/*
	2	* Copyright (C) 2020 EfficiOS, Inc.
	3	*
	4	* SPDX-License-Identifier: GPL-2.0-only
	5	*
	6	*/
	7
c9e313bc	8	#include "uprobe.hpp"
0c4e727b JR	9
	10	#include <sys/types.h>
	11	#include <sys/stat.h>
	12	#include <unistd.h>
	13
c9e313bc SM	14	#include "common/compat/getenv.hpp"
	15	#include "common/string-utils/string-utils.hpp"
	16	#include "common/utils.hpp"
	17	#include "common/path.hpp"
0c4e727b JR	18	#include "lttng/constant.h"
0c4e727b JR	19
c9e313bc	20	#include "command.hpp"
0c4e727b JR	21
	22	/*
	23	* Walk the directories in the PATH environment variable to find the target
	24	* binary passed as parameter.
	25	*
	26	* On success, the full path of the binary is copied in binary_full_path out
	27	* parameter. This buffer is allocated by the caller and must be at least
	28	* LTTNG_PATH_MAX bytes long.
	29	* On failure, returns -1;
	30	*/
	31	static
	32	int walk_command_search_path(const char binary, char binary_full_path)
	33	{
	34	char *tentative_binary_path = NULL;
	35	char *command_search_path = NULL;
	36	char *curr_search_dir_end = NULL;
	37	char *curr_search_dir = NULL;
	38	struct stat stat_output;
	39	int ret = 0;
	40
	41	command_search_path = lttng_secure_getenv("PATH");
	42	if (!command_search_path) {
	43	ret = -1;
	44	goto end;
	45	}
	46
	47	/*
	48	* Duplicate the $PATH string as the char pointer returned by getenv() should
	49	* not be modified.
	50	*/
	51	command_search_path = strdup(command_search_path);
	52	if (!command_search_path) {
	53	ret = -1;
	54	goto end;
	55	}
	56
	57	/*
	58	* This char array is used to concatenate path to binary to look for
	59	* the binary.
	60	*/
64803277	61	tentative_binary_path = calloc<char>(LTTNG_PATH_MAX);
0c4e727b JR	62	if (!tentative_binary_path) {
	63	ret = -1;
	64	goto alloc_error;
	65	}
	66
	67	curr_search_dir = command_search_path;
	68	do {
	69	/*
	70	* Split on ':'. The return value of this call points to the
	71	* matching character.
	72	*/
	73	curr_search_dir_end = strchr(curr_search_dir, ':');
	74	if (curr_search_dir_end != NULL) {
	75	/*
	76	* Add a NULL byte to the end of the first token so it
	77	* can be used as a string.
	78	*/
	79	curr_search_dir_end[0] = '\0';
	80	}
	81
	82	/* Empty the tentative path */
	83	memset(tentative_binary_path, 0, LTTNG_PATH_MAX * sizeof(char));
	84
	85	/*
	86	* Build the tentative path to the binary using the current
	87	* search directory and the name of the binary.
	88	*/
	89	ret = snprintf(tentative_binary_path, LTTNG_PATH_MAX, "%s/%s",
	90	curr_search_dir, binary);
	91	if (ret < 0) {
	92	goto free_binary_path;
	93	}
	94	if (ret < LTTNG_PATH_MAX) {
	95	/*
	96	* Use STAT(2) to see if the file exists.
	97	*/
	98	ret = stat(tentative_binary_path, &stat_output);
	99	if (ret == 0) {
	100	/*
	101	* Verify that it is a regular file or a
	102	* symlink and not a special file (e.g.
	103	* device).
	104	*/
	105	if (S_ISREG(stat_output.st_mode)
	106	\|\| S_ISLNK(stat_output.st_mode)) {
	107	/*
	108	* Found a match, set the out parameter
	109	* and return success.
	110	*/
	111	ret = lttng_strncpy(binary_full_path,
	112	tentative_binary_path,
	113	LTTNG_PATH_MAX);
	114	if (ret == -1) {
	115	ERR("Source path does not fit "
	116	"in destination buffer.");
	117	}
	118	goto free_binary_path;
	119	}
	120	}
	121	}
	122	/* Go to the next entry in the $PATH variable. */
	123	curr_search_dir = curr_search_dir_end + 1;
	124	} while (curr_search_dir_end != NULL);
	125
126	free_binary_path:
127	free(tentative_binary_path);
128	alloc_error:
129	free(command_search_path);
130	end:
131	return ret;
132	}
133
134	/*
135	* Check if the symbol field passed by the user is in fact an address or an
136	* offset from a symbol. Those two instrumentation types are not supported yet.
137	* It's expected to be a common mistake because of the existing --probe option
138	* that does support these formats.
139	*
140	* Here are examples of these unsupported formats for the --userspace-probe
141	* option:
142	* elf:/path/to/binary:0x400430
143	* elf:/path/to/binary:4194364
144	* elf:/path/to/binary:my_symbol+0x323
145	* elf:/path/to/binary:my_symbol+43
146	*/
147	static
148	int warn_userspace_probe_syntax(const char *symbol)
149	{
150	int ret;
151
152	/* Check if the symbol field is an hex address. */
153	ret = sscanf(symbol, "0x%*x");
154	if (ret > 0) {
155	/* If there is a match, print a warning and return an error. */
156	ERR("Userspace probe on address not supported yet.");
157	ret = CMD_UNSUPPORTED;
158	goto error;
159	}
160
161	/* Check if the symbol field is an decimal address. */
162	ret = sscanf(symbol, "%*u");
163	if (ret > 0) {
164	/* If there is a match, print a warning and return an error. */
165	ERR("Userspace probe on address not supported yet.");
166	ret = CMD_UNSUPPORTED;
167	goto error;
168	}
169
170	/* Check if the symbol field is symbol+hex_offset. */
171	ret = sscanf(symbol, "%[^+]+0x%x");
172	if (ret > 0) {
173	/* If there is a match, print a warning and return an error. */
174	ERR("Userspace probe on symbol+offset not supported yet.");
175	ret = CMD_UNSUPPORTED;
176	goto error;
177	}
178
179	/* Check if the symbol field is symbol+decimal_offset. */
180	ret = sscanf(symbol, "%[^+]+%u");
181	if (ret > 0) {
182	/* If there is a match, print a warning and return an error. */
183	ERR("Userspace probe on symbol+offset not supported yet.");
184	ret = CMD_UNSUPPORTED;
185	goto error;
186	}
187
188	ret = 0;
189
190	error:
191	return ret;
192	}
193
194	/*
195	* Parse userspace probe options
196	* Set the userspace probe fields in the lttng_event struct and set the
197	* target_path to the path to the binary.
198	*/
0c4e727b JR	199	int parse_userspace_probe_opts(const char *opt,
	200	struct lttng_userspace_probe_location **probe_location)
	201	{
	202	int ret = CMD_SUCCESS;
e358ddd5	203	size_t num_token = 0;
0c4e727b JR	204	char *target_path = NULL;
	205	char *unescaped_target_path = NULL;
	206	char *real_target_path = NULL;
	207	char symbol_name = NULL, probe_name = NULL, *provider_name = NULL;
	208	struct lttng_userspace_probe_location *probe_location_local = NULL;
	209	struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL;
e358ddd5	210	struct lttng_dynamic_pointer_array tokens;
0c4e727b	211
a0377dfe	212	LTTNG_ASSERT(opt);
0c4e727b JR	213
	214	/*
	215	* userspace probe fields are separated by ':'.
	216	*/
e358ddd5 JG	217	ret = strutils_split(opt, ':', true, &tokens);
	218	if (ret == 0) {
	219	num_token = lttng_dynamic_pointer_array_get_count(&tokens);
	220	}
0c4e727b JR	221
	222	/*
	223	* Early sanity check that the number of parameter is between 2 and 4
	224	* inclusively.
	225	* elf:PATH:SYMBOL
	226	* std:PATH:PROVIDER_NAME:PROBE_NAME
	227	* PATH:SYMBOL (same behavior as ELF)
	228	*/
e358ddd5	229	if (ret < 0 \|\| num_token < 2 \|\| num_token > 4) {
0c4e727b JR	230	ret = CMD_ERROR;
	231	goto end;
	232	}
	233
	234	/*
	235	* Looking up the first parameter will tell the technique to use to
	236	* interpret the userspace probe/function description.
	237	*/
	238	switch (num_token) {
	239	case 2:
	240	/* When the probe type is omitted we assume ELF for now. */
	241	case 3:
48a40005 SM	242	if (num_token == 3 && strcmp((const char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 0), "elf") == 0) {
	243	target_path = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 1);
	244	symbol_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 2);
0c4e727b	245	} else if (num_token == 2) {
48a40005 SM	246	target_path = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 0);
48a40005 SM	247	symbol_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 1);
0c4e727b JR	248	} else {
	249	ret = CMD_ERROR;
	250	goto end;
	251	}
	252	lookup_method =
	253	lttng_userspace_probe_location_lookup_method_function_elf_create();
	254	if (!lookup_method) {
	255	WARN("Failed to create ELF lookup method");
	256	ret = CMD_ERROR;
	257	goto end;
	258	}
	259	break;
	260	case 4:
48a40005 SM	261	if (strcmp((const char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 0), "sdt") == 0) {
	262	target_path = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 1);
	263	provider_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 2);
	264	probe_name = (char *) lttng_dynamic_pointer_array_get_pointer(&tokens, 3);
0c4e727b JR	265	} else {
	266	ret = CMD_ERROR;
	267	goto end;
	268	}
	269	lookup_method =
	270	lttng_userspace_probe_location_lookup_method_tracepoint_sdt_create();
	271	if (!lookup_method) {
	272	WARN("Failed to create SDT lookup method");
	273	ret = CMD_ERROR;
	274	goto end;
	275	}
	276	break;
	277	default:
	278	ret = CMD_ERROR;
	279	goto end;
	280	}
	281
	282	/* strutils_unescape_string allocates a new char . /
	283	unescaped_target_path = strutils_unescape_string(target_path, 0);
	284	if (!unescaped_target_path) {
	285	ret = CMD_ERROR;
	286	goto end;
	287	}
	288
	289	/*
	290	* If there is not forward slash in the path. Walk the $PATH else
	291	* expand.
	292	*/
	293	if (strchr(unescaped_target_path, '/') == NULL) {
	294	/* Walk the $PATH variable to find the targeted binary. */
64803277	295	real_target_path = calloc<char>(LTTNG_PATH_MAX);
0c4e727b JR	296	if (!real_target_path) {
	297	PERROR("Error allocating path buffer");
	298	ret = CMD_ERROR;
	299	goto end;
	300	}
	301	ret = walk_command_search_path(unescaped_target_path, real_target_path);
	302	if (ret) {
	303	ERR("Binary not found.");
	304	ret = CMD_ERROR;
	305	goto end;
	306	}
	307	} else {
	308	/*
	309	* Expand references to `/./` and `/../`. This function does not check
	310	* if the file exists. This call returns an allocated buffer on
	311	* success.
	312	*/
	313	real_target_path = utils_expand_path_keep_symlink(unescaped_target_path);
	314	if (!real_target_path) {
	315	ERR("Error expanding the path to binary.");
	316	ret = CMD_ERROR;
	317	goto end;
	318	}
	319
	320	/*
	321	* Check if the file exists using access(2), If it does not,
	322	* return an error.
	323	*/
	324	ret = access(real_target_path, F_OK);
	325	if (ret) {
	326	ERR("Cannot find binary at path: %s.", real_target_path);
	327	ret = CMD_ERROR;
	328	goto end;
	329	}
	330	}
	331
	332	switch (lttng_userspace_probe_location_lookup_method_get_type(lookup_method)) {
	333	case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
	334	/*
	335	* Check for common mistakes in userspace probe description syntax.
	336	*/
	337	ret = warn_userspace_probe_syntax(symbol_name);
	338	if (ret) {
	339	goto end;
	340	}
	341
	342	probe_location_local = lttng_userspace_probe_location_function_create(
	343	real_target_path, symbol_name, lookup_method);
	344	if (!probe_location_local) {
	345	WARN("Failed to create function probe location");
	346	ret = CMD_ERROR;
	347	goto end;
	348	}
	349
	350	/* Ownership transferred to probe_location. */
	351	lookup_method = NULL;
	352	break;
	353	case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
	354	probe_location_local = lttng_userspace_probe_location_tracepoint_create(
	355	real_target_path, provider_name, probe_name, lookup_method);
	356	if (!probe_location_local) {
	357	WARN("Failed to create function probe location");
	358	ret = CMD_ERROR;
	359	goto end;
360	}
361
362	/* Ownership transferred to probe_location. */
363	lookup_method = NULL;
364	break;
365	default:
366	ret = CMD_ERROR;
367	goto end;
368	}
369
370	/*
371	* Everything went fine, transfer ownership of probe location to
372	* caller.
373	*/
374	*probe_location = probe_location_local;
375	probe_location_local = NULL;
376
377	end:
378	lttng_userspace_probe_location_destroy(probe_location_local);
379	lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
e358ddd5	380	lttng_dynamic_pointer_array_reset(&tokens);
0c4e727b JR	381	/*
	382	* Freeing both char * here makes the error handling simplier. free()
	383	* performs not action if the pointer is NULL.
	384	*/
	385	free(real_target_path);
	386	free(unescaped_target_path);
	387
	388	return ret;
	389	}