perf tools: Add trace event information parser

Add util/trace-event-parse.c which provides the handlers to
parse the ftrace events info from the stream and handles the
ftrace perf samples event printing.

This file is a rename of the parse-events.c file from the
trace-cmd tools, written by Steven Rostedt and Josh Triplett,
originated from the git tree:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git

This is a perf tools integration.

[ fweisbec@gmail.com: various changes for perf tools
                      integration. ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: "Luis Claudio R. Goncalves" <lclaudio@uudg.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Jon Masters <jonathan@jonmasters.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Anton Blanchard <anton@samba.org>
LKML-Reference: <1250518688-7207-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2905 insertions, 0 deletions

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
new file mode 100644
index 00000000000..ead6a9ad359
--- /dev/null
+++ b/tools/perf/util/trace-event-parse.c
@@ -0,0 +1,2905 @@
+/*
+ * Copyright (C) 2009, Steven Rostedt <srostedt@redhat.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License (not later!)
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  The parts for function graph printing was taken and modified from the
+ *  Linux Kernel that were written by Frederic Weisbecker.
+ */
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+
+#undef _GNU_SOURCE
+#include "util.h"
+#include "trace-event.h"
+
+int header_page_ts_offset;
+int header_page_ts_size;
+int header_page_size_offset;
+int header_page_size_size;
+int header_page_data_offset;
+int header_page_data_size;
+
+static char *input_buf;
+static unsigned long long input_buf_ptr;
+static unsigned long long input_buf_siz;
+
+static int cpus;
+static int long_size;
+
+static void init_input_buf(char *buf, unsigned long long size)
+{
+	input_buf = buf;
+	input_buf_siz = size;
+	input_buf_ptr = 0;
+}
+
+struct cmdline {
+	char *comm;
+	int pid;
+};
+
+static struct cmdline *cmdlines;
+static int cmdline_count;
+
+static int cmdline_cmp(const void *a, const void *b)
+{
+	const struct cmdline *ca = a;
+	const struct cmdline *cb = b;
+
+	if (ca->pid < cb->pid)
+		return -1;
+	if (ca->pid > cb->pid)
+		return 1;
+
+	return 0;
+}
+
+void parse_cmdlines(char *file, int size __unused)
+{
+	struct cmdline_list {
+		struct cmdline_list	*next;
+		char			*comm;
+		int			pid;
+	} *list = NULL, *item;
+	char *line;
+	char *next = NULL;
+	int i;
+
+	line = strtok_r(file, "\n", &next);
+	while (line) {
+		item = malloc_or_die(sizeof(*item));
+		sscanf(line, "%d %as", &item->pid,
+		       (float *)&item->comm); /* workaround gcc warning */
+		item->next = list;
+		list = item;
+		line = strtok_r(NULL, "\n", &next);
+		cmdline_count++;
+	}
+
+	cmdlines = malloc_or_die(sizeof(*cmdlines) * cmdline_count);
+
+	i = 0;
+	while (list) {
+		cmdlines[i].pid = list->pid;
+		cmdlines[i].comm = list->comm;
+		i++;
+		item = list;
+		list = list->next;
+		free(item);
+	}
+
+	qsort(cmdlines, cmdline_count, sizeof(*cmdlines), cmdline_cmp);
+}
+
+static struct func_map {
+	unsigned long long		addr;
+	char				*func;
+	char				*mod;
+} *func_list;
+static unsigned int func_count;
+
+static int func_cmp(const void *a, const void *b)
+{
+	const struct func_map *fa = a;
+	const struct func_map *fb = b;
+
+	if (fa->addr < fb->addr)
+		return -1;
+	if (fa->addr > fb->addr)
+		return 1;
+
+	return 0;
+}
+
+void parse_proc_kallsyms(char *file, unsigned int size __unused)
+{
+	struct func_list {
+		struct func_list	*next;
+		unsigned long long	addr;
+		char			*func;
+		char			*mod;
+	} *list = NULL, *item;
+	char *line;
+	char *next = NULL;
+	char *addr_str;
+	char ch;
+	int ret;
+	int i;
+
+	line = strtok_r(file, "\n", &next);
+	while (line) {
+		item = malloc_or_die(sizeof(*item));
+		item->mod = NULL;
+		ret = sscanf(line, "%as %c %as\t[%as",
+			     (float *)&addr_str, /* workaround gcc warning */
+			     &ch,
+			     (float *)&item->func,
+			     (float *)&item->mod);
+		item->addr = strtoull(addr_str, NULL, 16);
+		free(addr_str);
+
+		/* truncate the extra ']' */
+		if (item->mod)
+			item->mod[strlen(item->mod) - 1] = 0;
+
+
+		item->next = list;
+		list = item;
+		line = strtok_r(NULL, "\n", &next);
+		func_count++;
+	}
+
+	func_list = malloc_or_die(sizeof(*func_list) * func_count + 1);
+
+	i = 0;
+	while (list) {
+		func_list[i].func = list->func;
+		func_list[i].addr = list->addr;
+		func_list[i].mod = list->mod;
+		i++;
+		item = list;
+		list = list->next;
+		free(item);
+	}
+
+	qsort(func_list, func_count, sizeof(*func_list), func_cmp);
+
+	/*
+	 * Add a special record at the end.
+	 */
+	func_list[func_count].func = NULL;
+	func_list[func_count].addr = 0;
+	func_list[func_count].mod = NULL;
+}
+
+/*
+ * We are searching for a record in between, not an exact
+ * match.
+ */
+static int func_bcmp(const void *a, const void *b)
+{
+	const struct func_map *fa = a;
+	const struct func_map *fb = b;
+
+	if ((fa->addr == fb->addr) ||
+
+	    (fa->addr > fb->addr &&
+	     fa->addr < (fb+1)->addr))
+		return 0;
+
+	if (fa->addr < fb->addr)
+		return -1;
+
+	return 1;
+}
+
+static struct func_map *find_func(unsigned long long addr)
+{
+	struct func_map *func;
+	struct func_map key;
+
+	key.addr = addr;
+
+	func = bsearch(&key, func_list, func_count, sizeof(*func_list),
+		       func_bcmp);
+
+	return func;
+}
+
+void print_funcs(void)
+{
+	int i;
+
+	for (i = 0; i < (int)func_count; i++) {
+		printf("%016llx %s",
+		       func_list[i].addr,
+		       func_list[i].func);
+		if (func_list[i].mod)
+			printf(" [%s]\n", func_list[i].mod);
+		else
+			printf("\n");
+	}
+}
+
+static struct printk_map {
+	unsigned long long		addr;
+	char				*printk;
+} *printk_list;
+static unsigned int printk_count;
+
+static int printk_cmp(const void *a, const void *b)
+{
+	const struct func_map *fa = a;
+	const struct func_map *fb = b;
+
+	if (fa->addr < fb->addr)
+		return -1;
+	if (fa->addr > fb->addr)
+		return 1;
+
+	return 0;
+}
+
+static struct printk_map *find_printk(unsigned long long addr)
+{
+	struct printk_map *printk;
+	struct printk_map key;
+
+	key.addr = addr;
+
+	printk = bsearch(&key, printk_list, printk_count, sizeof(*printk_list),
+			 printk_cmp);
+
+	return printk;
+}
+
+void parse_ftrace_printk(char *file, unsigned int size __unused)
+{
+	struct printk_list {
+		struct printk_list	*next;
+		unsigned long long	addr;
+		char			*printk;
+	} *list = NULL, *item;
+	char *line;
+	char *next = NULL;
+	char *addr_str;
+	int ret;
+	int i;
+
+	line = strtok_r(file, "\n", &next);
+	while (line) {
+		item = malloc_or_die(sizeof(*item));
+		ret = sscanf(line, "%as : %as",
+			     (float *)&addr_str, /* workaround gcc warning */
+			     (float *)&item->printk);
+		item->addr = strtoull(addr_str, NULL, 16);
+		free(addr_str);
+
+		item->next = list;
+		list = item;
+		line = strtok_r(NULL, "\n", &next);
+		printk_count++;
+	}
+
+	printk_list = malloc_or_die(sizeof(*printk_list) * printk_count + 1);
+
+	i = 0;
+	while (list) {
+		printk_list[i].printk = list->printk;
+		printk_list[i].addr = list->addr;
+		i++;
+		item = list;
+		list = list->next;
+		free(item);
+	}
+
+	qsort(printk_list, printk_count, sizeof(*printk_list), printk_cmp);
+}
+
+void print_printk(void)
+{
+	int i;
+
+	for (i = 0; i < (int)printk_count; i++) {
+		printf("%016llx %s\n",
+		       printk_list[i].addr,
+		       printk_list[i].printk);
+	}
+}
+
+static struct event *alloc_event(void)
+{
+	struct event *event;
+
+	event = malloc_or_die(sizeof(*event));
+	memset(event, 0, sizeof(*event));
+
+	return event;
+}
+
+enum event_type {
+	EVENT_ERROR,
+	EVENT_NONE,
+	EVENT_SPACE,
+	EVENT_NEWLINE,
+	EVENT_OP,
+	EVENT_DELIM,
+	EVENT_ITEM,
+	EVENT_DQUOTE,
+	EVENT_SQUOTE,
+};
+
+static struct event *event_list;
+
+static void add_event(struct event *event)
+{
+	event->next = event_list;
+	event_list = event;
+}
+
+static int event_item_type(enum event_type type)
+{
+	switch (type) {
+	case EVENT_ITEM ... EVENT_SQUOTE:
+		return 1;
+	case EVENT_ERROR ... EVENT_DELIM:
+	default:
+		return 0;
+	}
+}
+
+static void free_arg(struct print_arg *arg)
+{
+	if (!arg)
+		return;
+
+	switch (arg->type) {
+	case PRINT_ATOM:
+		if (arg->atom.atom)
+			free(arg->atom.atom);
+		break;
+	case PRINT_NULL:
+	case PRINT_FIELD ... PRINT_OP:
+	default:
+		/* todo */
+		break;
+	}
+
+	free(arg);
+}
+
+static enum event_type get_type(int ch)
+{
+	if (ch == '\n')
+		return EVENT_NEWLINE;
+	if (isspace(ch))
+		return EVENT_SPACE;
+	if (isalnum(ch) || ch == '_')
+		return EVENT_ITEM;
+	if (ch == '\'')
+		return EVENT_SQUOTE;
+	if (ch == '"')
+		return EVENT_DQUOTE;
+	if (!isprint(ch))
+		return EVENT_NONE;
+	if (ch == '(' || ch == ')' || ch == ',')
+		return EVENT_DELIM;
+
+	return EVENT_OP;
+}
+
+static int __read_char(void)
+{
+	if (input_buf_ptr >= input_buf_siz)
+		return -1;
+
+	return input_buf[input_buf_ptr++];
+}
+
+static int __peek_char(void)
+{
+	if (input_buf_ptr >= input_buf_siz)
+		return -1;
+
+	return input_buf[input_buf_ptr];
+}
+
+static enum event_type __read_token(char **tok)
+{
+	char buf[BUFSIZ];
+	int ch, last_ch, quote_ch, next_ch;
+	int i = 0;
+	int tok_size = 0;
+	enum event_type type;
+
+	*tok = NULL;
+
+
+	ch = __read_char();
+	if (ch < 0)
+		return EVENT_NONE;
+
+	type = get_type(ch);
+	if (type == EVENT_NONE)
+		return type;
+
+	buf[i++] = ch;
+
+	switch (type) {
+	case EVENT_NEWLINE:
+	case EVENT_DELIM:
+		*tok = malloc_or_die(2);
+		(*tok)[0] = ch;
+		(*tok)[1] = 0;
+		return type;
+
+	case EVENT_OP:
+		switch (ch) {
+		case '-':
+			next_ch = __peek_char();
+			if (next_ch == '>') {
+				buf[i++] = __read_char();
+				break;
+			}
+			/* fall through */
+		case '+':
+		case '|':
+		case '&':
+		case '>':
+		case '<':
+			last_ch = ch;
+			ch = __peek_char();
+			if (ch != last_ch)
+				goto test_equal;
+			buf[i++] = __read_char();
+			switch (last_ch) {
+			case '>':
+			case '<':
+				goto test_equal;
+			default:
+				break;
+			}
+			break;
+		case '!':
+		case '=':
+			goto test_equal;
+		default: /* what should we do instead? */
+			break;
+		}
+		buf[i] = 0;
+		*tok = strdup(buf);
+		return type;
+
+ test_equal:
+		ch = __peek_char();
+		if (ch == '=')
+			buf[i++] = __read_char();
+		break;
+
+	case EVENT_DQUOTE:
+	case EVENT_SQUOTE:
+		/* don't keep quotes */
+		i--;
+		quote_ch = ch;
+		last_ch = 0;
+		do {
+			if (i == (BUFSIZ - 1)) {
+				buf[i] = 0;
+				if (*tok) {
+					*tok = realloc(*tok, tok_size + BUFSIZ);
+					if (!*tok)
+						return EVENT_NONE;
+					strcat(*tok, buf);
+				} else
+					*tok = strdup(buf);
+
+				if (!*tok)
+					return EVENT_NONE;
+				tok_size += BUFSIZ;
+				i = 0;
+			}
+			last_ch = ch;
+			ch = __read_char();
+			buf[i++] = ch;
+		} while (ch != quote_ch && last_ch != '\\');
+		/* remove the last quote */
+		i--;
+		goto out;
+
+	case EVENT_ERROR ... EVENT_SPACE:
+	case EVENT_ITEM:
+	default:
+		break;
+	}
+
+	while (get_type(__peek_char()) == type) {
+		if (i == (BUFSIZ - 1)) {
+			buf[i] = 0;
+			if (*tok) {
+				*tok = realloc(*tok, tok_size + BUFSIZ);
+				if (!*tok)
+					return EVENT_NONE;
+				strcat(*tok, buf);
+			} else
+				*tok = strdup(buf);
+
+			if (!*tok)
+				return EVENT_NONE;
+			tok_size += BUFSIZ;
+			i = 0;
+		}
+		ch = __read_char();
+		buf[i++] = ch;
+	}
+
+ out:
+	buf[i] = 0;
+	if (*tok) {
+		*tok = realloc(*tok, tok_size + i);
+		if (!*tok)
+			return EVENT_NONE;
+		strcat(*tok, buf);
+	} else
+		*tok = strdup(buf);
+	if (!*tok)
+		return EVENT_NONE;
+
+	return type;
+}
+
+static void free_token(char *tok)
+{
+	if (tok)
+		free(tok);
+}
+
+static enum event_type read_token(char **tok)
+{
+	enum event_type type;
+
+	for (;;) {
+		type = __read_token(tok);
+		if (type != EVENT_SPACE)
+			return type;
+
+		free_token(*tok);
+	}
+
+	/* not reached */
+	return EVENT_NONE;
+}
+
+/* no newline */
+static enum event_type read_token_item(char **tok)
+{
+	enum event_type type;
+
+	for (;;) {
+		type = __read_token(tok);
+		if (type != EVENT_SPACE && type != EVENT_NEWLINE)
+			return type;
+
+		free_token(*tok);
+	}
+
+	/* not reached */
+	return EVENT_NONE;
+}
+
+static int test_type(enum event_type type, enum event_type expect)
+{
+	if (type != expect) {
+		die("Error: expected type %d but read %d",
+		    expect, type);
+		return -1;
+	}
+	return 0;
+}
+
+static int test_type_token(enum event_type type, char *token,
+		    enum event_type expect, char *expect_tok)
+{
+	if (type != expect) {
+		die("Error: expected type %d but read %d",
+		    expect, type);
+		return -1;
+	}
+
+	if (strcmp(token, expect_tok) != 0) {
+		die("Error: expected '%s' but read '%s'",
+		    expect_tok, token);
+		return -1;
+	}
+	return 0;
+}
+
+static int __read_expect_type(enum event_type expect, char **tok, int newline_ok)
+{
+	enum event_type type;
+
+	if (newline_ok)
+		type = read_token(tok);
+	else
+		type = read_token_item(tok);
+	return test_type(type, expect);
+}
+
+static int read_expect_type(enum event_type expect, char **tok)
+{
+	return __read_expect_type(expect, tok, 1);
+}
+
+static int __read_expected(enum event_type expect, char *str, int newline_ok)
+{
+	enum event_type type;
+	char *token;
+	int ret;
+
+	if (newline_ok)
+		type = read_token(&token);
+	else
+		type = read_token_item(&token);
+
+	ret = test_type_token(type, token, expect, str);
+
+	free_token(token);
+
+	return 0;
+}
+
+static int read_expected(enum event_type expect, char *str)
+{
+	return __read_expected(expect, str, 1);
+}
+
+static int read_expected_item(enum event_type expect, char *str)
+{
+	return __read_expected(expect, str, 0);
+}
+
+static char *event_read_name(void)
+{
+	char *token;
+
+	if (read_expected(EVENT_ITEM, (char *)"name") < 0)
+		return NULL;
+
+	if (read_expected(EVENT_OP, (char *)":") < 0)
+		return NULL;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+
+	return token;
+
+ fail:
+	free_token(token);
+	return NULL;
+}
+
+static int event_read_id(void)
+{
+	char *token;
+	int id;
+
+	if (read_expected_item(EVENT_ITEM, (char *)"ID") < 0)
+		return -1;
+
+	if (read_expected(EVENT_OP, (char *)":") < 0)
+		return -1;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+
+	id = strtoul(token, NULL, 0);
+	free_token(token);
+	return id;
+
+ fail:
+	free_token(token);
+	return -1;
+}
+
+static int event_read_fields(struct event *event, struct format_field **fields)
+{
+	struct format_field *field = NULL;
+	enum event_type type;
+	char *token;
+	char *last_token;
+	int count = 0;
+
+	do {
+		type = read_token(&token);
+		if (type == EVENT_NEWLINE) {
+			free_token(token);
+			return count;
+		}
+
+		count++;
+
+		if (test_type_token(type, token, EVENT_ITEM, (char *)"field"))
+			goto fail;
+		free_token(token);
+
+		type = read_token(&token);
+		/*
+		 * The ftrace fields may still use the "special" name.
+		 * Just ignore it.
+		 */
+		if (event->flags & EVENT_FL_ISFTRACE &&
+		    type == EVENT_ITEM && strcmp(token, "special") == 0) {
+			free_token(token);
+			type = read_token(&token);
+		}
+
+		if (test_type_token(type, token, EVENT_OP, (char *)":") < 0)
+			return -1;
+
+		if (read_expect_type(EVENT_ITEM, &token) < 0)
+			goto fail;
+
+		last_token = token;
+
+		field = malloc_or_die(sizeof(*field));
+		memset(field, 0, sizeof(*field));
+
+		/* read the rest of the type */
+		for (;;) {
+			type = read_token(&token);
+			if (type == EVENT_ITEM ||
+			    (type == EVENT_OP && strcmp(token, "*") == 0) ||
+			    /*
+			     * Some of the ftrace fields are broken and have
+			     * an illegal "." in them.
+			     */
+			    (event->flags & EVENT_FL_ISFTRACE &&
+			     type == EVENT_OP && strcmp(token, ".") == 0)) {
+
+				if (strcmp(token, "*") == 0)
+					field->flags |= FIELD_IS_POINTER;
+
+				if (field->type) {
+					field->type = realloc(field->type,
+							      strlen(field->type) +
+							      strlen(last_token) + 2);
+					strcat(field->type, " ");
+					strcat(field->type, last_token);
+				} else
+					field->type = last_token;
+				last_token = token;
+				continue;
+			}
+
+			break;
+		}
+
+		if (!field->type) {
+			die("no type found");
+			goto fail;
+		}
+		field->name = last_token;
+
+		if (test_type(type, EVENT_OP))
+			goto fail;
+
+		if (strcmp(token, "[") == 0) {
+			enum event_type last_type = type;
+			char *brackets = token;
+			int len;
+
+			field->flags |= FIELD_IS_ARRAY;
+
+			type = read_token(&token);
+		        while (strcmp(token, "]") != 0) {
+				if (last_type == EVENT_ITEM &&
+				    type == EVENT_ITEM)
+					len = 2;
+				else
+					len = 1;
+				last_type = type;
+
+				brackets = realloc(brackets,
+						   strlen(brackets) +
+						   strlen(token) + len);
+				if (len == 2)
+					strcat(brackets, " ");
+				strcat(brackets, token);
+				free_token(token);
+				type = read_token(&token);
+				if (type == EVENT_NONE) {
+					die("failed to find token");
+					goto fail;
+				}
+			}
+
+			free_token(token);
+
+			brackets = realloc(brackets, strlen(brackets) + 2);
+			strcat(brackets, "]");
+
+			/* add brackets to type */
+
+			type = read_token(&token);
+			/*
+			 * If the next token is not an OP, then it is of
+			 * the format: type [] item;
+			 */
+			if (type == EVENT_ITEM) {
+				field->type = realloc(field->type,
+						      strlen(field->type) +
+						      strlen(field->name) +
+						      strlen(brackets) + 2);
+				strcat(field->type, " ");
+				strcat(field->type, field->name);
+				free_token(field->name);
+				strcat(field->type, brackets);
+				field->name = token;
+				type = read_token(&token);
+			} else {
+				field->type = realloc(field->type,
+						      strlen(field->type) +
+						      strlen(brackets) + 1);
+				strcat(field->type, brackets);
+			}
+			free(brackets);
+		}
+
+		if (test_type_token(type, token,  EVENT_OP, (char *)";"))
+			goto fail;
+		free_token(token);
+
+		if (read_expected(EVENT_ITEM, (char *)"offset") < 0)
+			goto fail_expect;
+
+		if (read_expected(EVENT_OP, (char *)":") < 0)
+			goto fail_expect;
+
+		if (read_expect_type(EVENT_ITEM, &token))
+			goto fail;
+		field->offset = strtoul(token, NULL, 0);
+		free_token(token);
+
+		if (read_expected(EVENT_OP, (char *)";") < 0)
+			goto fail_expect;
+
+		if (read_expected(EVENT_ITEM, (char *)"size") < 0)
+			goto fail_expect;
+
+		if (read_expected(EVENT_OP, (char *)":") < 0)
+			goto fail_expect;
+
+		if (read_expect_type(EVENT_ITEM, &token))
+			goto fail;
+		field->size = strtoul(token, NULL, 0);
+		free_token(token);
+
+		if (read_expected(EVENT_OP, (char *)";") < 0)
+			goto fail_expect;
+
+		if (read_expect_type(EVENT_NEWLINE, &token) < 0)
+			goto fail;
+		free_token(token);
+
+		*fields = field;
+		fields = &field->next;
+
+	} while (1);
+
+	return 0;
+
+fail:
+	free_token(token);
+fail_expect:
+	if (field)
+		free(field);
+	return -1;
+}
+
+static int event_read_format(struct event *event)
+{
+	char *token;
+	int ret;
+
+	if (read_expected_item(EVENT_ITEM, (char *)"format") < 0)
+		return -1;
+
+	if (read_expected(EVENT_OP, (char *)":") < 0)
+		return -1;
+
+	if (read_expect_type(EVENT_NEWLINE, &token))
+		goto fail;
+	free_token(token);
+
+	ret = event_read_fields(event, &event->format.common_fields);
+	if (ret < 0)
+		return ret;
+	event->format.nr_common = ret;
+
+	ret = event_read_fields(event, &event->format.fields);
+	if (ret < 0)
+		return ret;
+	event->format.nr_fields = ret;
+
+	return 0;
+
+ fail:
+	free_token(token);
+	return -1;
+}
+
+enum event_type
+process_arg_token(struct event *event, struct print_arg *arg,
+		  char **tok, enum event_type type);
+
+static enum event_type
+process_arg(struct event *event, struct print_arg *arg, char **tok)
+{
+	enum event_type type;
+	char *token;
+
+	type = read_token(&token);
+	*tok = token;
+
+	return process_arg_token(event, arg, tok, type);
+}
+
+static enum event_type
+process_cond(struct event *event, struct print_arg *top, char **tok)
+{
+	struct print_arg *arg, *left, *right;
+	enum event_type type;
+	char *token = NULL;
+
+	arg = malloc_or_die(sizeof(*arg));
+	memset(arg, 0, sizeof(*arg));
+
+	left = malloc_or_die(sizeof(*left));
+
+	right = malloc_or_die(sizeof(*right));
+
+	arg->type = PRINT_OP;
+	arg->op.left = left;
+	arg->op.right = right;
+
+	*tok = NULL;
+	type = process_arg(event, left, &token);
+	if (test_type_token(type, token, EVENT_OP, (char *)":"))
+		goto out_free;
+
+	arg->op.op = token;
+
+	type = process_arg(event, right, &token);
+
+	top->op.right = arg;
+
+	*tok = token;
+	return type;
+
+out_free:
+	free_token(*tok);
+	free(right);
+	free(left);
+	free_arg(arg);
+	return EVENT_ERROR;
+}
+
+static int get_op_prio(char *op)
+{
+	if (!op[1]) {
+		switch (op[0]) {
+		case '*':
+		case '/':
+		case '%':
+			return 6;
+		case '+':
+		case '-':
+			return 7;
+			/* '>>' and '<<' are 8 */
+		case '<':
+		case '>':
+			return 9;
+			/* '==' and '!=' are 10 */
+		case '&':
+			return 11;
+		case '^':
+			return 12;
+		case '|':
+			return 13;
+		case '?':
+			return 16;
+		default:
+			die("unknown op '%c'", op[0]);
+			return -1;
+		}
+	} else {
+		if (strcmp(op, "++") == 0 ||
+		    strcmp(op, "--") == 0) {
+			return 3;
+		} else if (strcmp(op, ">>") == 0 ||
+			   strcmp(op, "<<") == 0) {
+			return 8;
+		} else if (strcmp(op, ">=") == 0 ||
+			   strcmp(op, "<=") == 0) {
+			return 9;
+		} else if (strcmp(op, "==") == 0 ||
+			   strcmp(op, "!=") == 0) {
+			return 10;
+		} else if (strcmp(op, "&&") == 0) {
+			return 14;
+		} else if (strcmp(op, "||") == 0) {
+			return 15;
+		} else {
+			die("unknown op '%s'", op);
+			return -1;
+		}
+	}
+}
+
+static void set_op_prio(struct print_arg *arg)
+{
+
+	/* single ops are the greatest */
+	if (!arg->op.left || arg->op.left->type == PRINT_NULL) {
+		arg->op.prio = 0;
+		return;
+	}
+
+	arg->op.prio = get_op_prio(arg->op.op);
+}
+
+static enum event_type
+process_op(struct event *event, struct print_arg *arg, char **tok)
+{
+	struct print_arg *left, *right = NULL;
+	enum event_type type;
+	char *token;
+
+	/* the op is passed in via tok */
+	token = *tok;
+
+	if (arg->type == PRINT_OP && !arg->op.left) {
+		/* handle single op */
+		if (token[1]) {
+			die("bad op token %s", token);
+			return EVENT_ERROR;
+		}
+		switch (token[0]) {
+		case '!':
+		case '+':
+		case '-':
+			break;
+		default:
+			die("bad op token %s", token);
+			return EVENT_ERROR;
+		}
+
+		/* make an empty left */
+		left = malloc_or_die(sizeof(*left));
+		left->type = PRINT_NULL;
+		arg->op.left = left;
+
+		right = malloc_or_die(sizeof(*right));
+		arg->op.right = right;
+
+		type = process_arg(event, right, tok);
+
+	} else if (strcmp(token, "?") == 0) {
+
+		left = malloc_or_die(sizeof(*left));
+		/* copy the top arg to the left */
+		*left = *arg;
+
+		arg->type = PRINT_OP;
+		arg->op.op = token;
+		arg->op.left = left;
+		arg->op.prio = 0;
+
+		type = process_cond(event, arg, tok);
+
+	} else if (strcmp(token, ">>") == 0 ||
+		   strcmp(token, "<<") == 0 ||
+		   strcmp(token, "&") == 0 ||
+		   strcmp(token, "|") == 0 ||
+		   strcmp(token, "&&") == 0 ||
+		   strcmp(token, "||") == 0 ||
+		   strcmp(token, "-") == 0 ||
+		   strcmp(token, "+") == 0 ||
+		   strcmp(token, "*") == 0 ||
+		   strcmp(token, "^") == 0 ||
+		   strcmp(token, "/") == 0 ||
+		   strcmp(token, "==") == 0 ||
+		   strcmp(token, "!=") == 0) {
+
+		left = malloc_or_die(sizeof(*left));
+
+		/* copy the top arg to the left */
+		*left = *arg;
+
+		arg->type = PRINT_OP;
+		arg->op.op = token;
+		arg->op.left = left;
+
+		set_op_prio(arg);
+
+		right = malloc_or_die(sizeof(*right));
+
+		type = process_arg(event, right, tok);
+
+		arg->op.right = right;
+
+	} else {
+		die("unknown op '%s'", token);
+		/* the arg is now the left side */
+		return EVENT_NONE;
+	}
+
+
+	if (type == EVENT_OP) {
+		int prio;
+
+		/* higher prios need to be closer to the root */
+		prio = get_op_prio(*tok);
+
+		if (prio > arg->op.prio)
+			return process_op(event, arg, tok);
+
+		return process_op(event, right, tok);
+	}
+
+	return type;
+}
+
+static enum event_type
+process_entry(struct event *event __unused, struct print_arg *arg,
+	      char **tok)
+{
+	enum event_type type;
+	char *field;
+	char *token;
+
+	if (read_expected(EVENT_OP, (char *)"->") < 0)
+		return EVENT_ERROR;
+
+	if (read_expect_type(EVENT_ITEM, &token) < 0)
+		goto fail;
+	field = token;
+
+	arg->type = PRINT_FIELD;
+	arg->field.name = field;
+
+	type = read_token(&token);
+	*tok = token;
+
+	return type;
+
+fail:
+	free_token(token);
+	return EVENT_ERROR;
+}
+
+static char *arg_eval (struct print_arg *arg);
+
+static long long arg_num_eval(struct print_arg *arg)
+{
+	long long left, right;
+	long long val = 0;
+
+	switch (arg->type) {
+	case PRINT_ATOM:
+		val = strtoll(arg->atom.atom, NULL, 0);
+		break;
+	case PRINT_TYPE:
+		val = arg_num_eval(arg->typecast.item);
+		break;
+	case PRINT_OP:
+		switch (arg->op.op[0]) {
+		case '|':
+			left = arg_num_eval(arg->op.left);
+			right = arg_num_eval(arg->op.right);
+			if (arg->op.op[1])
+				val = left || right;
+			else
+				val = left | right;
+			break;
+		case '&':
+			left = arg_num_eval(arg->op.left);
+			right = arg_num_eval(arg->op.right);
+			if (arg->op.op[1])
+				val = left && right;
+			else
+				val = left & right;
+			break;
+		case '<':
+			left = arg_num_eval(arg->op.left);
+			right = arg_num_eval(arg->op.right);
+			switch (arg->op.op[1]) {
+			case 0:
+				val = left < right;
+				break;
+			case '<':
+				val = left << right;
+				break;
+			case '=':
+				val = left <= right;
+				break;
+			default:
+				die("unknown op '%s'", arg->op.op);
+			}
+			break;
+		case '>':
+			left = arg_num_eval(arg->op.left);
+			right = arg_num_eval(arg->op.right);
+			switch (arg->op.op[1]) {
+			case 0:
+				val = left > right;
+				break;
+			case '>':
+				val = left >> right;
+				break;
+			case '=':
+				val = left >= right;
+				break;
+			default:
+				die("unknown op '%s'", arg->op.op);
+			}
+			break;
+		case '=':
+			left = arg_num_eval(arg->op.left);
+			right = arg_num_eval(arg->op.right);
+
+			if (arg->op.op[1] != '=')
+				die("unknown op '%s'", arg->op.op);
+
+			val = left == right;
+			break;
+		case '!':
+			left = arg_num_eval(arg->op.left);
+			right = arg_num_eval(arg->op.right);
+
+			switch (arg->op.op[1]) {
+			case '=':
+				val = left != right;
+				break;
+			default:
+				die("unknown op '%s'", arg->op.op);
+			}
+			break;
+		default:
+			die("unknown op '%s'", arg->op.op);
+		}
+		break;
+
+	case PRINT_NULL:
+	case PRINT_FIELD ... PRINT_SYMBOL:
+	case PRINT_STRING:
+	default:
+		die("invalid eval type %d", arg->type);
+
+	}
+	return val;
+}
+
+static char *arg_eval (struct print_arg *arg)
+{
+	long long val;
+	static char buf[20];
+
+	switch (arg->type) {
+	case PRINT_ATOM:
+		return arg->atom.atom;
+	case PRINT_TYPE:
+		return arg_eval(arg->typecast.item);
+	case PRINT_OP:
+		val = arg_num_eval(arg);
+		sprintf(buf, "%lld", val);
+		return buf;
+
+	case PRINT_NULL:
+	case PRINT_FIELD ... PRINT_SYMBOL:
+	case PRINT_STRING:
+	default:
+		die("invalid eval type %d", arg->type);
+		break;
+	}
+
+	return NULL;