1 files changed, 478 insertions, 0 deletions
diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
new file mode 100644
index 000000000..8a01af783
--- /dev/null
+++ b/tools/perf/util/trace-event-read.c
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2009, Steven Rostedt <srostedt@redhat.com>
+ */
+#include <dirent.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "trace-event.h"
+#include "debug.h"
+
+static int input_fd;
+
+static ssize_t trace_data_size;
+static bool repipe;
+
+static int __do_read(int fd, void *buf, int size)
+{
+	int rsize = size;
+
+	while (size) {
+		int ret = read(fd, buf, size);
+
+		if (ret <= 0)
+			return -1;
+
+		if (repipe) {
+			int retw = write(STDOUT_FILENO, buf, ret);
+
+			if (retw <= 0 || retw != ret) {
+				pr_debug("repiping input file");
+				return -1;
+			}
+		}
+
+		size -= ret;
+		buf += ret;
+	}
+
+	return rsize;
+}
+
+static int do_read(void *data, int size)
+{
+	int r;
+
+	r = __do_read(input_fd, data, size);
+	if (r <= 0) {
+		pr_debug("reading input file (size expected=%d received=%d)",
+			 size, r);
+		return -1;
+	}
+
+	trace_data_size += r;
+
+	return r;
+}
+
+/* If it fails, the next read will report it */
+static void skip(int size)
+{
+	char buf[BUFSIZ];
+	int r;
+
+	while (size) {
+		r = size > BUFSIZ ? BUFSIZ : size;
+		do_read(buf, r);
+		size -= r;
+	}
+}
+
+static unsigned int read4(struct tep_handle *pevent)
+{
+	unsigned int data;
+
+	if (do_read(&data, 4) < 0)
+		return 0;
+	return tep_read_number(pevent, &data, 4);
+}
+
+static unsigned long long read8(struct tep_handle *pevent)
+{
+	unsigned long long data;
+
+	if (do_read(&data, 8) < 0)
+		return 0;
+	return tep_read_number(pevent, &data, 8);
+}
+
+static char *read_string(void)
+{
+	char buf[BUFSIZ];
+	char *str = NULL;
+	int size = 0;
+	off_t r;
+	char c;
+
+	for (;;) {
+		r = read(input_fd, &c, 1);
+		if (r < 0) {
+			pr_debug("reading input file");
+			goto out;
+		}
+
+		if (!r) {
+			pr_debug("no data");
+			goto out;
+		}
+
+		if (repipe) {
+			int retw = write(STDOUT_FILENO, &c, 1);
+
+			if (retw <= 0 || retw != r) {
+				pr_debug("repiping input file string");
+				goto out;
+			}
+		}
+
+		buf[size++] = c;
+
+		if (!c)
+			break;
+	}
+
+	trace_data_size += size;
+
+	str = malloc(size);
+	if (str)
+		memcpy(str, buf, size);
+out:
+	return str;
+}
+
+static int read_proc_kallsyms(struct tep_handle *pevent)
+{
+	unsigned int size;
+
+	size = read4(pevent);
+	if (!size)
+		return 0;
+	/*
+	 * Just skip it, now that we configure libtraceevent to use the
+	 * tools/perf/ symbol resolver.
+	 *
+	 * We need to skip it so that we can continue parsing old perf.data
+	 * files, that contains this /proc/kallsyms payload.
+	 *
+	 * Newer perf.data files will have just the 4-bytes zeros "kallsyms
+	 * payload", so that older tools can continue reading it and interpret
+	 * it as "no kallsyms payload is present".
+	 */
+	lseek(input_fd, size, SEEK_CUR);
+	trace_data_size += size;
+	return 0;
+}
+
+static int read_ftrace_printk(struct tep_handle *pevent)
+{
+	unsigned int size;
+	char *buf;
+
+	/* it can have 0 size */
+	size = read4(pevent);
+	if (!size)
+		return 0;
+
+	buf = malloc(size + 1);
+	if (buf == NULL)
+		return -1;
+
+	if (do_read(buf, size) < 0) {
+		free(buf);
+		return -1;
+	}
+
+	buf[size] = '\0';
+
+	parse_ftrace_printk(pevent, buf, size);
+
+	free(buf);
+	return 0;
+}
+
+static int read_header_files(struct tep_handle *pevent)
+{
+	unsigned long long size;
+	char *header_page;
+	char buf[BUFSIZ];
+	int ret = 0;
+
+	if (do_read(buf, 12) < 0)
+		return -1;
+
+	if (memcmp(buf, "header_page", 12) != 0) {
+		pr_debug("did not read header page");
+		return -1;
+	}
+
+	size = read8(pevent);
+
+	header_page = malloc(size);
+	if (header_page == NULL)
+		return -1;
+
+	if (do_read(header_page, size) < 0) {
+		pr_debug("did not read header page");
+		free(header_page);
+		return -1;
+	}
+
+	if (!tep_parse_header_page(pevent, header_page, size,
+				   tep_get_long_size(pevent))) {
+		/*
+		 * The commit field in the page is of type long,
+		 * use that instead, since it represents the kernel.
+		 */
+		tep_set_long_size(pevent, tep_get_header_page_size(pevent));
+	}
+	free(header_page);
+
+	if (do_read(buf, 13) < 0)
+		return -1;
+
+	if (memcmp(buf, "header_event", 13) != 0) {
+		pr_debug("did not read header event");
+		return -1;
+	}
+
+	size = read8(pevent);
+	skip(size);
+
+	return ret;
+}
+
+static int read_ftrace_file(struct tep_handle *pevent, unsigned long long size)
+{
+	int ret;
+	char *buf;
+
+	buf = malloc(size);
+	if (buf == NULL) {
+		pr_debug("memory allocation failure\n");
+		return -1;
+	}
+
+	ret = do_read(buf, size);
+	if (ret < 0) {
+		pr_debug("error reading ftrace file.\n");
+		goto out;
+	}
+
+	ret = parse_ftrace_file(pevent, buf, size);
+	if (ret < 0)
+		pr_debug("error parsing ftrace file.\n");
+out:
+	free(buf);
+	return ret;
+}
+
+static int read_event_file(struct tep_handle *pevent, char *sys,
+			   unsigned long long size)
+{
+	int ret;
+	char *buf;
+
+	buf = malloc(size);
+	if (buf == NULL) {
+		pr_debug("memory allocation failure\n");
+		return -1;
+	}
+
+	ret = do_read(buf, size);
+	if (ret < 0)
+		goto out;
+
+	ret = parse_event_file(pevent, buf, size, sys);
+	if (ret < 0)
+		pr_debug("error parsing event file.\n");
+out:
+	free(buf);
+	return ret;
+}
+
+static int read_ftrace_files(struct tep_handle *pevent)
+{
+	unsigned long long size;
+	int count;
+	int i;
+	int ret;
+
+	count = read4(pevent);
+
+	for (i = 0; i < count; i++) {
+		size = read8(pevent);
+		ret = read_ftrace_file(pevent, size);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static int read_event_files(struct tep_handle *pevent)
+{
+	unsigned long long size;
+	char *sys;
+	int systems;
+	int count;
+	int i,x;
+	int ret;
+
+	systems = read4(pevent);
+
+	for (i = 0; i < systems; i++) {
+		sys = read_string();
+		if (sys == NULL)
+			return -1;
+
+		count = read4(pevent);
+
+		for (x=0; x < count; x++) {
+			size = read8(pevent);
+			ret = read_event_file(pevent, sys, size);
+			if (ret) {
+				free(sys);
+				return ret;
+			}
+		}
+		free(sys);
+	}
+	return 0;
+}
+
+static int read_saved_cmdline(struct tep_handle *pevent)
+{
+	unsigned long long size;
+	char *buf;
+	int ret;
+
+	/* it can have 0 size */
+	size = read8(pevent);
+	if (!size)
+		return 0;
+
+	buf = malloc(size + 1);
+	if (buf == NULL) {
+		pr_debug("memory allocation failure\n");
+		return -1;
+	}
+
+	ret = do_read(buf, size);
+	if (ret < 0) {
+		pr_debug("error reading saved cmdlines\n");
+		goto out;
+	}
+	buf[ret] = '\0';
+
+	parse_saved_cmdline(pevent, buf, size);
+	ret = 0;
+out:
+	free(buf);
+	return ret;
+}
+
+ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
+{
+	char buf[BUFSIZ];
+	char test[] = { 23, 8, 68 };
+	char *version;
+	int show_version = 0;
+	int show_funcs = 0;
+	int show_printk = 0;
+	ssize_t size = -1;
+	int file_bigendian;
+	int host_bigendian;
+	int file_long_size;
+	int file_page_size;
+	struct tep_handle *pevent = NULL;
+	int err;
+
+	repipe = __repipe;
+	input_fd = fd;
+
+	if (do_read(buf, 3) < 0)
+		return -1;
+	if (memcmp(buf, test, 3) != 0) {
+		pr_debug("no trace data in the file");
+		return -1;
+	}
+
+	if (do_read(buf, 7) < 0)
+		return -1;
+	if (memcmp(buf, "tracing", 7) != 0) {
+		pr_debug("not a trace file (missing 'tracing' tag)");
+		return -1;
+	}
+
+	version = read_string();
+	if (version == NULL)
+		return -1;
+	if (show_version)
+		printf("version = %s\n", version);
+
+	if (do_read(buf, 1) < 0) {
+		free(version);
+		return -1;
+	}
+	file_bigendian = buf[0];
+	host_bigendian = bigendian();
+
+	if (trace_event__init(tevent)) {
+		pr_debug("trace_event__init failed");
+		goto out;
+	}
+
+	pevent = tevent->pevent;
+
+	tep_set_flag(pevent, TEP_NSEC_OUTPUT);
+	tep_set_file_bigendian(pevent, file_bigendian);
+	tep_set_local_bigendian(pevent, host_bigendian);
+
+	if (do_read(buf, 1) < 0)
+		goto out;
+	file_long_size = buf[0];
+
+	file_page_size = read4(pevent);
+	if (!file_page_size)
+		goto out;
+
+	tep_set_long_size(pevent, file_long_size);
+	tep_set_page_size(pevent, file_page_size);
+
+	err = read_header_files(pevent);
+	if (err)
+		goto out;
+	err = read_ftrace_files(pevent);
+	if (err)
+		goto out;
+	err = read_event_files(pevent);
+	if (err)
+		goto out;
+	err = read_proc_kallsyms(pevent);
+	if (err)
+		goto out;
+	err = read_ftrace_printk(pevent);
+	if (err)
+		goto out;
+	if (atof(version) >= 0.6) {
+		err = read_saved_cmdline(pevent);
+		if (err)
+			goto out;
+	}
+
+	size = trace_data_size;
+	repipe = false;
+
+	if (show_funcs) {
+		tep_print_funcs(pevent);
+	} else if (show_printk) {
+		tep_print_printk(pevent);
+	}
+
+	pevent = NULL;
+
+out:
+	if (pevent)
+		trace_event__cleanup(tevent);
+	free(version);
+	return size;
+}