From 4993071a89f88f92444cf62abdc0935efbc6c460 Mon Sep 17 00:00:00 2001
From: Philippe Proulx <eeppeliteloop@gmail.com>
Date: Sat, 18 Feb 2017 20:01:34 -0500
Subject: [PATCH] Add support for star globbing patterns in event names

This patch adds support for full star-only globbing patterns used in
the event names (enabler names).

strutils_star_glob_match() is always used to perform the match when
the enabler is LTTNG_ENABLER_STAR_GLOB. This enabler is set when it is
detected that its name contains at least one non-escaped star with
strutils_is_star_glob_pattern().

The match is performed by strutils_star_glob_match(), the same function
that the filter interpreter uses.

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 lttng-abi.c    |  9 +++++++--
 lttng-abi.h    |  2 +-
 lttng-events.c | 12 ++++++------
 lttng-events.h |  2 +-
 4 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/lttng-abi.c b/lttng-abi.c
index 40f96eb5..f2b207cb 100644
--- a/lttng-abi.c
+++ b/lttng-abi.c
@@ -51,6 +51,7 @@
 #include <wrapper/poll.h>
 #include <wrapper/file.h>
 #include <wrapper/kref.h>
+#include <lttng-string-utils.h>
 #include <lttng-abi.h>
 #include <lttng-abi-old.h>
 #include <lttng-events.h>
@@ -1068,8 +1069,12 @@ int lttng_abi_create_event(struct file *channel_file,
 			|| event_param->instrumentation == LTTNG_KERNEL_SYSCALL) {
 		struct lttng_enabler *enabler;
 
-		if (event_param->name[strlen(event_param->name) - 1] == '*') {
-			enabler = lttng_enabler_create(LTTNG_ENABLER_WILDCARD,
+		if (strutils_is_star_glob_pattern(event_param->name)) {
+			/*
+			 * If the event name is a star globbing pattern,
+			 * we create the special star globbing enabler.
+			 */
+			enabler = lttng_enabler_create(LTTNG_ENABLER_STAR_GLOB,
 				event_param, channel);
 		} else {
 			enabler = lttng_enabler_create(LTTNG_ENABLER_NAME,
diff --git a/lttng-abi.h b/lttng-abi.h
index 822b8839..dac86584 100644
--- a/lttng-abi.h
+++ b/lttng-abi.h
@@ -30,7 +30,7 @@
  * should be increased when an incompatible ABI change is done.
  */
 #define LTTNG_MODULES_ABI_MAJOR_VERSION		2
-#define LTTNG_MODULES_ABI_MINOR_VERSION		2
+#define LTTNG_MODULES_ABI_MINOR_VERSION		3
 
 #define LTTNG_KERNEL_SYM_NAME_LEN	256
 
diff --git a/lttng-events.c b/lttng-events.c
index d0070146..6bfe710f 100644
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -51,6 +51,7 @@
 #include <lttng-tracer.h>
 #include <lttng-abi-old.h>
 #include <lttng-endian.h>
+#include <lttng-string-utils.h>
 #include <wrapper/vzalloc.h>
 #include <wrapper/ringbuffer/backend.h>
 #include <wrapper/ringbuffer/frontend.h>
@@ -1142,11 +1143,10 @@ fd_error:
  * Enabler management.
  */
 static
-int lttng_match_enabler_wildcard(const char *desc_name,
-		const char *name)
+int lttng_match_enabler_star_glob(const char *desc_name,
+		const char *pattern)
 {
-	/* Compare excluding final '*' */
-	if (strncmp(desc_name, name, strlen(name) - 1))
+	if (!strutils_star_glob_match(pattern, -1ULL, desc_name, -1ULL))
 		return 0;
 	return 1;
 }
@@ -1191,8 +1191,8 @@ int lttng_desc_match_enabler(const struct lttng_event_desc *desc,
 		return -EINVAL;
 	}
 	switch (enabler->type) {
-	case LTTNG_ENABLER_WILDCARD:
-		return lttng_match_enabler_wildcard(desc_name, enabler_name);
+	case LTTNG_ENABLER_STAR_GLOB:
+		return lttng_match_enabler_star_glob(desc_name, enabler_name);
 	case LTTNG_ENABLER_NAME:
 		return lttng_match_enabler_name(desc_name, enabler_name);
 	default:
diff --git a/lttng-events.h b/lttng-events.h
index 173f369f..f55bf663 100644
--- a/lttng-events.h
+++ b/lttng-events.h
@@ -324,7 +324,7 @@ struct lttng_event {
 };
 
 enum lttng_enabler_type {
-	LTTNG_ENABLER_WILDCARD,
+	LTTNG_ENABLER_STAR_GLOB,
 	LTTNG_ENABLER_NAME,
 };
 
-- 
2.34.1