tools lib traceevent: Add support for __print_hex()

Since the __print_hex() function is used in print fmt now, add
corresponding parser routines. This makes the output of perf script on
the kvm_emulate_insn event not to fail any more.

 before:
      kvm_emulate_insn:     [FAILED TO PARSE] rip=3238197797 ...

 after:
      kvm_emulate_insn:     0:c102fa25:89 10 (prot32)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1340757701-10711-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 63d02be..b1abd39 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -697,6 +697,10 @@
 		free_arg(arg->symbol.field);
 		free_flag_sym(arg->symbol.symbols);
 		break;
+	case PRINT_HEX:
+		free_arg(arg->hex.field);
+		free_arg(arg->hex.size);
+		break;
 	case PRINT_TYPE:
 		free(arg->typecast.type);
 		free_arg(arg->typecast.item);
@@ -2260,6 +2264,45 @@
 }
 
 static enum event_type
+process_hex(struct event_format *event, struct print_arg *arg, char **tok)
+{
+	struct print_arg *field;
+	enum event_type type;
+	char *token;
+
+	memset(arg, 0, sizeof(*arg));
+	arg->type = PRINT_HEX;
+
+	field = alloc_arg();
+	type = process_arg(event, field, &token);
+
+	if (test_type_token(type, token, EVENT_DELIM, ","))
+		goto out_free;
+
+	arg->hex.field = field;
+
+	free_token(token);
+
+	field = alloc_arg();
+	type = process_arg(event, field, &token);
+
+	if (test_type_token(type, token, EVENT_DELIM, ")"))
+		goto out_free;
+
+	arg->hex.size = field;
+
+	free_token(token);
+	type = read_token_item(tok);
+	return type;
+
+ out_free:
+	free_arg(field);
+	free_token(token);
+	*tok = NULL;
+	return EVENT_ERROR;
+}
+
+static enum event_type
 process_dynamic_array(struct event_format *event, struct print_arg *arg, char **tok)
 {
 	struct format_field *field;
@@ -2488,6 +2531,10 @@
 		is_symbolic_field = 1;
 		return process_symbols(event, arg, tok);
 	}
+	if (strcmp(token, "__print_hex") == 0) {
+		free_token(token);
+		return process_hex(event, arg, tok);
+	}
 	if (strcmp(token, "__get_str") == 0) {
 		free_token(token);
 		return process_str(event, arg, tok);
@@ -2995,6 +3042,7 @@
 		break;
 	case PRINT_FLAGS:
 	case PRINT_SYMBOL:
+	case PRINT_HEX:
 		break;
 	case PRINT_TYPE:
 		val = eval_num_arg(data, size, event, arg->typecast.item);
@@ -3218,8 +3266,9 @@
 	unsigned long long val, fval;
 	unsigned long addr;
 	char *str;
+	unsigned char *hex;
 	int print;
-	int len;
+	int i, len;
 
 	switch (arg->type) {
 	case PRINT_NULL:
@@ -3284,6 +3333,23 @@
 			}
 		}
 		break;
+	case PRINT_HEX:
+		field = arg->hex.field->field.field;
+		if (!field) {
+			str = arg->hex.field->field.name;
+			field = pevent_find_any_field(event, str);
+			if (!field)
+				die("field %s not found", str);
+			arg->hex.field->field.field = field;
+		}
+		hex = data + field->offset;
+		len = eval_num_arg(data, size, event, arg->hex.size);
+		for (i = 0; i < len; i++) {
+			if (i)
+				trace_seq_putc(s, ' ');
+			trace_seq_printf(s, "%02x", hex[i]);
+		}
+		break;
 
 	case PRINT_TYPE:
 		break;
@@ -4294,6 +4360,13 @@
 		trace_seq_destroy(&s);
 		printf(")");
 		break;
+	case PRINT_HEX:
+		printf("__print_hex(");
+		print_args(args->hex.field);
+		printf(", ");
+		print_args(args->hex.size);
+		printf(")");
+		break;
 	case PRINT_STRING:
 	case PRINT_BSTRING:
 		printf("__get_str(%s)", args->string.string);