1#include <sys/types.h>
2#include <unistd.h>
3#include <stdio.h>
4#include <stdlib.h>
5
6#include "util.h"
7#include "header.h"
8
9
10
11
12struct perf_header_attr *perf_header_attr__new(struct perf_event_attr *attr)
13{
14 struct perf_header_attr *self = malloc(sizeof(*self));
15
16 if (!self)
17 die("nomem");
18
19 self->attr = *attr;
20 self->ids = 0;
21 self->size = 1;
22 self->id = malloc(sizeof(u64));
23
24 if (!self->id)
25 die("nomem");
26
27 return self;
28}
29
30void perf_header_attr__add_id(struct perf_header_attr *self, u64 id)
31{
32 int pos = self->ids;
33
34 self->ids++;
35 if (self->ids > self->size) {
36 self->size *= 2;
37 self->id = realloc(self->id, self->size * sizeof(u64));
38 if (!self->id)
39 die("nomem");
40 }
41 self->id[pos] = id;
42}
43
44
45
46
47struct perf_header *perf_header__new(void)
48{
49 struct perf_header *self = malloc(sizeof(*self));
50
51 if (!self)
52 die("nomem");
53
54 self->frozen = 0;
55
56 self->attrs = 0;
57 self->size = 1;
58 self->attr = malloc(sizeof(void *));
59
60 if (!self->attr)
61 die("nomem");
62
63 self->data_offset = 0;
64 self->data_size = 0;
65
66 return self;
67}
68
69void perf_header__add_attr(struct perf_header *self,
70 struct perf_header_attr *attr)
71{
72 int pos = self->attrs;
73
74 if (self->frozen)
75 die("frozen");
76
77 self->attrs++;
78 if (self->attrs > self->size) {
79 self->size *= 2;
80 self->attr = realloc(self->attr, self->size * sizeof(void *));
81 if (!self->attr)
82 die("nomem");
83 }
84 self->attr[pos] = attr;
85}
86
87#define MAX_EVENT_NAME 64
88
89struct perf_trace_event_type {
90 u64 event_id;
91 char name[MAX_EVENT_NAME];
92};
93
94static int event_count;
95static struct perf_trace_event_type *events;
96
97void perf_header__push_event(u64 id, const char *name)
98{
99 if (strlen(name) > MAX_EVENT_NAME)
100 printf("Event %s will be truncated\n", name);
101
102 if (!events) {
103 events = malloc(sizeof(struct perf_trace_event_type));
104 if (!events)
105 die("nomem");
106 } else {
107 events = realloc(events, (event_count + 1) * sizeof(struct perf_trace_event_type));
108 if (!events)
109 die("nomem");
110 }
111 memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
112 events[event_count].event_id = id;
113 strncpy(events[event_count].name, name, MAX_EVENT_NAME - 1);
114 event_count++;
115}
116
117char *perf_header__find_event(u64 id)
118{
119 int i;
120 for (i = 0 ; i < event_count; i++) {
121 if (events[i].event_id == id)
122 return events[i].name;
123 }
124 return NULL;
125}
126
127static const char *__perf_magic = "PERFFILE";
128
129#define PERF_MAGIC (*(u64 *)__perf_magic)
130
131struct perf_file_section {
132 u64 offset;
133 u64 size;
134};
135
136struct perf_file_attr {
137 struct perf_event_attr attr;
138 struct perf_file_section ids;
139};
140
141struct perf_file_header {
142 u64 magic;
143 u64 size;
144 u64 attr_size;
145 struct perf_file_section attrs;
146 struct perf_file_section data;
147 struct perf_file_section event_types;
148};
149
150static void do_write(int fd, void *buf, size_t size)
151{
152 while (size) {
153 int ret = write(fd, buf, size);
154
155 if (ret < 0)
156 die("failed to write");
157
158 size -= ret;
159 buf += ret;
160 }
161}
162
163void perf_header__write(struct perf_header *self, int fd)
164{
165 struct perf_file_header f_header;
166 struct perf_file_attr f_attr;
167 struct perf_header_attr *attr;
168 int i;
169
170 lseek(fd, sizeof(f_header), SEEK_SET);
171
172
173 for (i = 0; i < self->attrs; i++) {
174 attr = self->attr[i];
175
176 attr->id_offset = lseek(fd, 0, SEEK_CUR);
177 do_write(fd, attr->id, attr->ids * sizeof(u64));
178 }
179
180
181 self->attr_offset = lseek(fd, 0, SEEK_CUR);
182
183 for (i = 0; i < self->attrs; i++) {
184 attr = self->attr[i];
185
186 f_attr = (struct perf_file_attr){
187 .attr = attr->attr,
188 .ids = {
189 .offset = attr->id_offset,
190 .size = attr->ids * sizeof(u64),
191 }
192 };
193 do_write(fd, &f_attr, sizeof(f_attr));
194 }
195
196 self->event_offset = lseek(fd, 0, SEEK_CUR);
197 self->event_size = event_count * sizeof(struct perf_trace_event_type);
198 if (events)
199 do_write(fd, events, self->event_size);
200
201
202 self->data_offset = lseek(fd, 0, SEEK_CUR);
203
204 f_header = (struct perf_file_header){
205 .magic = PERF_MAGIC,
206 .size = sizeof(f_header),
207 .attr_size = sizeof(f_attr),
208 .attrs = {
209 .offset = self->attr_offset,
210 .size = self->attrs * sizeof(f_attr),
211 },
212 .data = {
213 .offset = self->data_offset,
214 .size = self->data_size,
215 },
216 .event_types = {
217 .offset = self->event_offset,
218 .size = self->event_size,
219 },
220 };
221
222 lseek(fd, 0, SEEK_SET);
223 do_write(fd, &f_header, sizeof(f_header));
224 lseek(fd, self->data_offset + self->data_size, SEEK_SET);
225
226 self->frozen = 1;
227}
228
229static void do_read(int fd, void *buf, size_t size)
230{
231 while (size) {
232 int ret = read(fd, buf, size);
233
234 if (ret < 0)
235 die("failed to read");
236 if (ret == 0)
237 die("failed to read: missing data");
238
239 size -= ret;
240 buf += ret;
241 }
242}
243
244struct perf_header *perf_header__read(int fd)
245{
246 struct perf_header *self = perf_header__new();
247 struct perf_file_header f_header;
248 struct perf_file_attr f_attr;
249 u64 f_id;
250
251 int nr_attrs, nr_ids, i, j;
252
253 lseek(fd, 0, SEEK_SET);
254 do_read(fd, &f_header, sizeof(f_header));
255
256 if (f_header.magic != PERF_MAGIC ||
257 f_header.size != sizeof(f_header) ||
258 f_header.attr_size != sizeof(f_attr))
259 die("incompatible file format");
260
261 nr_attrs = f_header.attrs.size / sizeof(f_attr);
262 lseek(fd, f_header.attrs.offset, SEEK_SET);
263
264 for (i = 0; i < nr_attrs; i++) {
265 struct perf_header_attr *attr;
266 off_t tmp;
267
268 do_read(fd, &f_attr, sizeof(f_attr));
269 tmp = lseek(fd, 0, SEEK_CUR);
270
271 attr = perf_header_attr__new(&f_attr.attr);
272
273 nr_ids = f_attr.ids.size / sizeof(u64);
274 lseek(fd, f_attr.ids.offset, SEEK_SET);
275
276 for (j = 0; j < nr_ids; j++) {
277 do_read(fd, &f_id, sizeof(f_id));
278
279 perf_header_attr__add_id(attr, f_id);
280 }
281 perf_header__add_attr(self, attr);
282 lseek(fd, tmp, SEEK_SET);
283 }
284
285 if (f_header.event_types.size) {
286 lseek(fd, f_header.event_types.offset, SEEK_SET);
287 events = malloc(f_header.event_types.size);
288 if (!events)
289 die("nomem");
290 do_read(fd, events, f_header.event_types.size);
291 event_count = f_header.event_types.size / sizeof(struct perf_trace_event_type);
292 }
293 self->event_offset = f_header.event_types.offset;
294 self->event_size = f_header.event_types.size;
295
296 self->data_offset = f_header.data.offset;
297 self->data_size = f_header.data.size;
298
299 lseek(fd, self->data_offset, SEEK_SET);
300
301 self->frozen = 1;
302
303 return self;
304}
305
306u64 perf_header__sample_type(struct perf_header *header)
307{
308 u64 type = 0;
309 int i;
310
311 for (i = 0; i < header->attrs; i++) {
312 struct perf_header_attr *attr = header->attr[i];
313
314 if (!type)
315 type = attr->attr.sample_type;
316 else if (type != attr->attr.sample_type)
317 die("non matching sample_type");
318 }
319
320 return type;
321}
322
323struct perf_event_attr *
324perf_header__find_attr(u64 id, struct perf_header *header)
325{
326 int i;
327
328 for (i = 0; i < header->attrs; i++) {
329 struct perf_header_attr *attr = header->attr[i];
330 int j;
331
332 for (j = 0; j < attr->ids; j++) {
333 if (attr->id[j] == id)
334 return &attr->attr;
335 }
336 }
337
338 return NULL;
339}
340
