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
goto end;
}
+ switch (ev->type) {
+ case LTTNG_EVENT_USERSPACE_PROBE:
+ break;
+ default:
+ assert(0);
+ }
+
/*
* userspace probe fields are separated by ':'.
*/
/* strutils_unescape_string allocates a new char *. */
unescaped_target_path = strutils_unescape_string(target_path, 0);
if (!unescaped_target_path) {
- ret = -LTTNG_ERR_INVALID;
- goto end_string;
+ ret = CMD_ERROR;
+ goto end_destroy_lookup_method;
}
/*
* If there is not forward slash in the path. Walk the $PATH else
* expand.
*/
- if (strchr(target_path, '/') == NULL) {
+ if (strchr(unescaped_target_path, '/') == NULL) {
/* Walk the $PATH variable to find the targeted binary. */
real_target_path = zmalloc(LTTNG_PATH_MAX * sizeof(char));
if (!real_target_path) {
PERROR("Error allocating path buffer");
ret = CMD_ERROR;
- goto end_unescaped_string;
+ goto end_destroy_lookup_method;
}
- ret = walk_command_search_path(target_path, real_target_path);
+ ret = walk_command_search_path(unescaped_target_path, real_target_path);
if (ret) {
ERR("Binary not found.");
ret = CMD_ERROR;
- goto end_free_path;
+ goto end_destroy_lookup_method;
}
} else {
/*
* Expand references to `/./` and `/../`. This function does not check
- * if the file exists.
+ * if the file exists. This call returns an allocated buffer on
+ * success.
*/
- real_target_path = utils_expand_path_keep_symlink(target_path);
+ 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_free_path;
+ goto end_destroy_lookup_method;
}
/*
*/
ret = access(real_target_path, F_OK);
if (ret) {
+ ERR("Cannot find binary at path: %s.", real_target_path);
ret = CMD_ERROR;
- goto end_free_path;
+ goto end_destroy_lookup_method;
}
}
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_destroy_lookup_method;
+ }
+
probe_location = lttng_userspace_probe_location_function_create(
real_target_path, symbol_name, lookup_method);
if (!probe_location) {
break;
default:
ret = CMD_ERROR;
- goto end_string;
+ goto end_destroy_lookup_method;
}
- switch (ev->type) {
- case LTTNG_EVENT_USERSPACE_PROBE:
- break;
- default:
- assert(0);
- }
-
- goto end;
+ /* Successful parsing, now clean up everything and return. */
+ goto end_string;
end_destroy_location:
lttng_userspace_probe_location_destroy(probe_location);
end_destroy_lookup_method:
lttng_userspace_probe_location_lookup_method_destroy(lookup_method);
-end_free_path:
+end_string:
+ strutils_free_null_terminated_array_of_strings(tokens);
/*
- * Free path that was allocated by the call to realpath() or when walking
- * the PATH.
+ * Freeing both char * here makes the error handling simplier. free()
+ * performs not action if the pointer is NULL.
*/
free(real_target_path);
-end_unescaped_string:
free(unescaped_target_path);
-end_string:
- strutils_free_null_terminated_array_of_strings(tokens);
end:
return ret;
}
}
}
+ /*
+ * Adding a filter to a probe, function or userspace-probe would be
+ * denied by the kernel tracer as it's not supported at the moment. We
+ * do an early check here to warn the user.
+ */
+ if (opt_filter && opt_kernel) {
+ switch (opt_event_type) {
+ case LTTNG_EVENT_ALL:
+ case LTTNG_EVENT_TRACEPOINT:
+ case LTTNG_EVENT_SYSCALL:
+ break;
+ case LTTNG_EVENT_PROBE:
+ case LTTNG_EVENT_USERSPACE_PROBE:
+ case LTTNG_EVENT_FUNCTION:
+ ERR("Filter expressions are not supported for %s events",
+ get_event_type_str(opt_event_type));
+ ret = CMD_ERROR;
+ goto error;
+ default:
+ ret = CMD_UNDEFINED;
+ goto error;
+ }
+ }
+
channel_name = opt_channel_name;
handle = lttng_create_handle(session_name, &dom);
case LTTNG_EVENT_USERSPACE_PROBE:
ret = parse_userspace_probe_opts(ev, opt_userspace_probe);
if (ret) {
- ERR("Unable to parse userspace probe options");
- ret = CMD_ERROR;
+ switch (ret) {
+ case CMD_UNSUPPORTED:
+ /*
+ * Error message describing
+ * what is not supported was
+ * printed in the function.
+ */
+ break;
+ case CMD_ERROR:
+ default:
+ ERR("Unable to parse userspace probe options");
+ break;
+ }
goto error;
}
break;
projects / lttng-tools.git / blobdiff