1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2009, Steven Rostedt <srostedt@redhat.com>
10 #include <sys/types.h>
18 #include "trace-event.h"
23 static ssize_t trace_data_size;
26 static int __do_read(int fd, void *buf, int size)
31 int ret = read(fd, buf, size);
37 int retw = write(STDOUT_FILENO, buf, ret);
39 if (retw <= 0 || retw != ret) {
40 pr_debug("repiping input file");
52 static int do_read(void *data, int size)
56 r = __do_read(input_fd, data, size);
58 pr_debug("reading input file (size expected=%d received=%d)",
68 /* If it fails, the next read will report it */
69 static void skip(int size)
75 r = size > BUFSIZ ? BUFSIZ : size;
81 static unsigned int read4(struct tep_handle *pevent)
85 if (do_read(&data, 4) < 0)
87 return tep_read_number(pevent, &data, 4);
90 static unsigned long long read8(struct tep_handle *pevent)
92 unsigned long long data;
94 if (do_read(&data, 8) < 0)
96 return tep_read_number(pevent, &data, 8);
99 static char *read_string(void)
108 r = read(input_fd, &c, 1);
110 pr_debug("reading input file");
120 int retw = write(STDOUT_FILENO, &c, 1);
122 if (retw <= 0 || retw != r) {
123 pr_debug("repiping input file string");
134 trace_data_size += size;
138 memcpy(str, buf, size);
143 static int read_proc_kallsyms(struct tep_handle *pevent)
147 size = read4(pevent);
151 * Just skip it, now that we configure libtraceevent to use the
152 * tools/perf/ symbol resolver.
154 * We need to skip it so that we can continue parsing old perf.data
155 * files, that contains this /proc/kallsyms payload.
157 * Newer perf.data files will have just the 4-bytes zeros "kallsyms
158 * payload", so that older tools can continue reading it and interpret
159 * it as "no kallsyms payload is present".
161 lseek(input_fd, size, SEEK_CUR);
162 trace_data_size += size;
166 static int read_ftrace_printk(struct tep_handle *pevent)
171 /* it can have 0 size */
172 size = read4(pevent);
176 buf = malloc(size + 1);
180 if (do_read(buf, size) < 0) {
187 parse_ftrace_printk(pevent, buf, size);
193 static int read_header_files(struct tep_handle *pevent)
195 unsigned long long size;
200 if (do_read(buf, 12) < 0)
203 if (memcmp(buf, "header_page", 12) != 0) {
204 pr_debug("did not read header page");
208 size = read8(pevent);
210 header_page = malloc(size);
211 if (header_page == NULL)
214 if (do_read(header_page, size) < 0) {
215 pr_debug("did not read header page");
220 if (!tep_parse_header_page(pevent, header_page, size,
221 tep_get_long_size(pevent))) {
223 * The commit field in the page is of type long,
224 * use that instead, since it represents the kernel.
226 tep_set_long_size(pevent, tep_get_header_page_size(pevent));
230 if (do_read(buf, 13) < 0)
233 if (memcmp(buf, "header_event", 13) != 0) {
234 pr_debug("did not read header event");
238 size = read8(pevent);
244 static int read_ftrace_file(struct tep_handle *pevent, unsigned long long size)
251 pr_debug("memory allocation failure\n");
255 ret = do_read(buf, size);
257 pr_debug("error reading ftrace file.\n");
261 ret = parse_ftrace_file(pevent, buf, size);
263 pr_debug("error parsing ftrace file.\n");
269 static int read_event_file(struct tep_handle *pevent, char *sys,
270 unsigned long long size)
277 pr_debug("memory allocation failure\n");
281 ret = do_read(buf, size);
285 ret = parse_event_file(pevent, buf, size, sys);
287 pr_debug("error parsing event file.\n");
293 static int read_ftrace_files(struct tep_handle *pevent)
295 unsigned long long size;
300 count = read4(pevent);
302 for (i = 0; i < count; i++) {
303 size = read8(pevent);
304 ret = read_ftrace_file(pevent, size);
311 static int read_event_files(struct tep_handle *pevent)
313 unsigned long long size;
320 systems = read4(pevent);
322 for (i = 0; i < systems; i++) {
327 count = read4(pevent);
329 for (x=0; x < count; x++) {
330 size = read8(pevent);
331 ret = read_event_file(pevent, sys, size);
342 static int read_saved_cmdline(struct tep_handle *pevent)
344 unsigned long long size;
348 /* it can have 0 size */
349 size = read8(pevent);
353 buf = malloc(size + 1);
355 pr_debug("memory allocation failure\n");
359 ret = do_read(buf, size);
361 pr_debug("error reading saved cmdlines\n");
366 parse_saved_cmdline(pevent, buf, size);
373 ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
376 char test[] = { 23, 8, 68 };
378 int show_version = 0;
386 struct tep_handle *pevent = NULL;
392 if (do_read(buf, 3) < 0)
394 if (memcmp(buf, test, 3) != 0) {
395 pr_debug("no trace data in the file");
399 if (do_read(buf, 7) < 0)
401 if (memcmp(buf, "tracing", 7) != 0) {
402 pr_debug("not a trace file (missing 'tracing' tag)");
406 version = read_string();
410 printf("version = %s\n", version);
412 if (do_read(buf, 1) < 0) {
416 file_bigendian = buf[0];
417 host_bigendian = bigendian();
419 if (trace_event__init(tevent)) {
420 pr_debug("trace_event__init failed");
424 pevent = tevent->pevent;
426 tep_set_flag(pevent, TEP_NSEC_OUTPUT);
427 tep_set_file_bigendian(pevent, file_bigendian);
428 tep_set_local_bigendian(pevent, host_bigendian);
430 if (do_read(buf, 1) < 0)
432 file_long_size = buf[0];
434 file_page_size = read4(pevent);
438 tep_set_long_size(pevent, file_long_size);
439 tep_set_page_size(pevent, file_page_size);
441 err = read_header_files(pevent);
444 err = read_ftrace_files(pevent);
447 err = read_event_files(pevent);
450 err = read_proc_kallsyms(pevent);
453 err = read_ftrace_printk(pevent);
456 if (atof(version) >= 0.6) {
457 err = read_saved_cmdline(pevent);
462 size = trace_data_size;
466 tep_print_funcs(pevent);
467 } else if (show_printk) {
468 tep_print_printk(pevent);
475 trace_event__cleanup(tevent);