1 files changed, 168 insertions, 0 deletions
diff --git a/lib/trace-cmd/trace-hooks.c b/lib/trace-cmd/trace-hooks.c
new file mode 100644
index 00000000..a58b5356
--- /dev/null
+++ b/lib/trace-cmd/trace-hooks.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (C) 2015 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+
+#include "trace-cmd-private.h"
+#include "trace-cmd-local.h"
+#include "event-utils.h"
+
+struct hook_list *tracecmd_create_event_hook(const char *arg)
+{
+	struct hook_list *hook;
+	char *system = NULL;
+	char *event;
+	char *match;
+	char *flags = NULL;
+	char *pid = NULL;
+	char *str;
+	char *tok;
+	int index;
+	int ch;
+	int i;
+
+	hook = malloc(sizeof(*hook));
+	if (!hook)
+		return NULL;
+	memset(hook, 0, sizeof(*hook));
+
+	str = strdup(arg);
+	if (!str) {
+		free(hook);
+		return NULL;
+	}
+
+	hook->str = str;
+	hook->hook = arg;
+
+	/*
+	 * Hooks are in the form of:
+	 *  [<start_system>:]<start_event>,<start_match>[,<start_pid>]/
+	 *  [<end_system>:]<end_event>,<end_match>[,<flags>]
+	 *
+	 * Where start_system, start_pid, end_system, and flags are all
+	 * optional.
+	 *
+	 * Flags are (case insensitive):
+	 *  P - pinned to cpu (wont migrate)
+	 *  G - global, not hooked to task - currently ignored.
+	 *  S - save stacks for this event.
+	 */
+	tok = strtok(str, ":,");
+	if (!tok)
+		goto invalid_tok;
+
+	/* See what the token was from the original arg */
+	index = strlen(tok);
+	if (arg[index] == ':') {
+		/* this is a system, the next token must be ',' */
+		system = tok;
+		tok = strtok(NULL, ",");
+		if (!tok)
+			goto invalid_tok;
+	}
+	event = tok;
+
+	tok = strtok(NULL, ",/");
+	if (!tok)
+		goto invalid_tok;
+	match = tok;
+	index = strlen(tok) + tok - str;
+	if (arg[index] == ',') {
+		tok = strtok(NULL, "/");
+		if (!tok)
+			goto invalid_tok;
+		pid = tok;
+	}
+
+	hook->start_system = system;
+	hook->start_event = event;
+	hook->start_match = match;
+	hook->pid = pid;
+
+	/* Now process the end event */
+	system = NULL;
+
+	tok = strtok(NULL, ":,");
+	if (!tok)
+		goto invalid_tok;
+
+	/* See what the token was from the original arg */
+	index = tok - str + strlen(tok);
+	if (arg[index] == ':') {
+		/* this is a system, the next token must be ',' */
+		system = tok;
+		tok = strtok(NULL, ",");
+		if (!tok)
+			goto invalid_tok;
+	}
+	event = tok;
+
+	tok = strtok(NULL, ",");
+	if (!tok)
+		goto invalid_tok;
+	match = tok;
+	index = strlen(tok) + tok - str;
+	if (arg[index] == ',') {
+		tok = strtok(NULL, "");
+		if (!tok)
+			goto invalid_tok;
+		flags = tok;
+	}
+
+	hook->end_system = system;
+	hook->end_event = event;
+	hook->end_match = match;
+	hook->migrate = 1;
+	if (flags) {
+		for (i = 0; flags[i]; i++) {
+			ch = tolower(flags[i]);
+			switch (ch) {
+			case 'p':
+				hook->migrate = 0;
+				break;
+			case 'g':
+				hook->global = 1;
+				break;
+			case 's':
+				hook->stack = 1;
+				break;
+			default:
+				tracecmd_warning("unknown flag %c", flags[i]);
+			}
+		}
+	}
+
+	printf("start %s:%s:%s (%s) end %s:%s:%s (%s)\n",
+	       hook->start_system,
+	       hook->start_event,
+	       hook->start_match,
+	       hook->pid,
+	       hook->end_system,
+	       hook->end_event,
+	       hook->end_match,
+	       flags);
+	return hook;
+
+invalid_tok:
+	tracecmd_warning("Invalid hook format '%s'", arg);
+	return NULL;
+}
+
+void tracecmd_free_hooks(struct hook_list *hooks)
+{
+	struct hook_list *hook;
+
+	while (hooks) {
+		hook = hooks;
+		hooks = hooks->next;
+
+		free(hook->str);
+		free(hook);
+	}
+}