f204a7d88a03261403f2f93b5525ac2cc4646446
1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) 2000-2002 Michael R. Elkins <me@mutt.org>
5 * Copyright (C) 2002-2004 Oswald Buddenhagen <ossi@users.sf.net>
6 * Copyright (C) 2004 Theodore Y. Ts'o <tytso@mit.edu>
7 * Copyright (C) 2006 Mike McCormack
8 * Copyright (C) 2006 Christian Couder
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24
25#include "cache.h"
26#include "quote.h"
27
28/*
29 * "Normalize" a key argument by converting NULL to our trace_default,
30 * and otherwise passing through the value. All caller-facing functions
31 * should normalize their inputs in this way, though most get it
32 * for free by calling get_trace_fd() (directly or indirectly).
33 */
34static void normalize_trace_key(struct trace_key **key)
35{
36 static struct trace_key trace_default = { "GIT_TRACE" };
37 if (!*key)
38 *key = &trace_default;
39}
40
41/* Get a trace file descriptor from "key" env variable. */
42static int get_trace_fd(struct trace_key *key)
43{
44 const char *trace;
45
46 normalize_trace_key(&key);
47
48 /* don't open twice */
49 if (key->initialized)
50 return key->fd;
51
52 trace = getenv(key->key);
53
54 if (!trace || !strcmp(trace, "") ||
55 !strcmp(trace, "0") || !strcasecmp(trace, "false"))
56 key->fd = 0;
57 else if (!strcmp(trace, "1") || !strcasecmp(trace, "true"))
58 key->fd = STDERR_FILENO;
59 else if (strlen(trace) == 1 && isdigit(*trace))
60 key->fd = atoi(trace);
61 else if (is_absolute_path(trace)) {
62 int fd = open(trace, O_WRONLY | O_APPEND | O_CREAT, 0666);
63 if (fd == -1) {
64 fprintf(stderr,
65 "Could not open '%s' for tracing: %s\n"
66 "Defaulting to tracing on stderr...\n",
67 trace, strerror(errno));
68 key->fd = STDERR_FILENO;
69 } else {
70 key->fd = fd;
71 key->need_close = 1;
72 }
73 } else {
74 fprintf(stderr, "What does '%s' for %s mean?\n"
75 "If you want to trace into a file, then please set "
76 "%s to an absolute pathname (starting with /).\n"
77 "Defaulting to tracing on stderr...\n",
78 trace, key->key, key->key);
79 key->fd = STDERR_FILENO;
80 }
81
82 key->initialized = 1;
83 return key->fd;
84}
85
86void trace_disable(struct trace_key *key)
87{
88 normalize_trace_key(&key);
89
90 if (key->need_close)
91 close(key->fd);
92 key->fd = 0;
93 key->initialized = 1;
94 key->need_close = 0;
95}
96
97static const char err_msg[] = "Could not trace into fd given by "
98 "GIT_TRACE environment variable";
99
100static int prepare_trace_line(const char *file, int line,
101 struct trace_key *key, struct strbuf *buf)
102{
103 static struct trace_key trace_bare = TRACE_KEY_INIT(BARE);
104 struct timeval tv;
105 struct tm tm;
106 time_t secs;
107
108 if (!trace_want(key))
109 return 0;
110
111 set_try_to_free_routine(NULL); /* is never reset */
112
113 /* unit tests may want to disable additional trace output */
114 if (trace_want(&trace_bare))
115 return 1;
116
117 /* print current timestamp */
118 gettimeofday(&tv, NULL);
119 secs = tv.tv_sec;
120 localtime_r(&secs, &tm);
121 strbuf_addf(buf, "%02d:%02d:%02d.%06ld ", tm.tm_hour, tm.tm_min,
122 tm.tm_sec, (long) tv.tv_usec);
123
124#ifdef HAVE_VARIADIC_MACROS
125 /* print file:line */
126 strbuf_addf(buf, "%s:%d ", file, line);
127 /* align trace output (column 40 catches most files names in git) */
128 while (buf->len < 40)
129 strbuf_addch(buf, ' ');
130#endif
131
132 return 1;
133}
134
135void trace_verbatim(struct trace_key *key, const void *buf, unsigned len)
136{
137 if (!trace_want(key))
138 return;
139 write_or_whine_pipe(get_trace_fd(key), buf, len, err_msg);
140}
141
142static void print_trace_line(struct trace_key *key, struct strbuf *buf)
143{
144 strbuf_complete_line(buf);
145
146 write_or_whine_pipe(get_trace_fd(key), buf->buf, buf->len, err_msg);
147 strbuf_release(buf);
148}
149
150static void trace_vprintf_fl(const char *file, int line, struct trace_key *key,
151 const char *format, va_list ap)
152{
153 struct strbuf buf = STRBUF_INIT;
154
155 if (!prepare_trace_line(file, line, key, &buf))
156 return;
157
158 strbuf_vaddf(&buf, format, ap);
159 print_trace_line(key, &buf);
160}
161
162static void trace_argv_vprintf_fl(const char *file, int line,
163 const char **argv, const char *format,
164 va_list ap)
165{
166 struct strbuf buf = STRBUF_INIT;
167
168 if (!prepare_trace_line(file, line, NULL, &buf))
169 return;
170
171 strbuf_vaddf(&buf, format, ap);
172
173 sq_quote_argv(&buf, argv, 0);
174 print_trace_line(NULL, &buf);
175}
176
177void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
178 const struct strbuf *data)
179{
180 struct strbuf buf = STRBUF_INIT;
181
182 if (!prepare_trace_line(file, line, key, &buf))
183 return;
184
185 strbuf_addbuf(&buf, data);
186 print_trace_line(key, &buf);
187}
188
189static struct trace_key trace_perf_key = TRACE_KEY_INIT(PERFORMANCE);
190
191static void trace_performance_vprintf_fl(const char *file, int line,
192 uint64_t nanos, const char *format,
193 va_list ap)
194{
195 struct strbuf buf = STRBUF_INIT;
196
197 if (!prepare_trace_line(file, line, &trace_perf_key, &buf))
198 return;
199
200 strbuf_addf(&buf, "performance: %.9f s", (double) nanos / 1000000000);
201
202 if (format && *format) {
203 strbuf_addstr(&buf, ": ");
204 strbuf_vaddf(&buf, format, ap);
205 }
206
207 print_trace_line(&trace_perf_key, &buf);
208}
209
210#ifndef HAVE_VARIADIC_MACROS
211
212void trace_printf(const char *format, ...)
213{
214 va_list ap;
215 va_start(ap, format);
216 trace_vprintf_fl(NULL, 0, NULL, format, ap);
217 va_end(ap);
218}
219
220void trace_printf_key(struct trace_key *key, const char *format, ...)
221{
222 va_list ap;
223 va_start(ap, format);
224 trace_vprintf_fl(NULL, 0, key, format, ap);
225 va_end(ap);
226}
227
228void trace_argv_printf(const char **argv, const char *format, ...)
229{
230 va_list ap;
231 va_start(ap, format);
232 trace_argv_vprintf_fl(NULL, 0, argv, format, ap);
233 va_end(ap);
234}
235
236void trace_strbuf(struct trace_key *key, const struct strbuf *data)
237{
238 trace_strbuf_fl(NULL, 0, key, data);
239}
240
241void trace_performance(uint64_t nanos, const char *format, ...)
242{
243 va_list ap;
244 va_start(ap, format);
245 trace_performance_vprintf_fl(NULL, 0, nanos, format, ap);
246 va_end(ap);
247}
248
249void trace_performance_since(uint64_t start, const char *format, ...)
250{
251 va_list ap;
252 va_start(ap, format);
253 trace_performance_vprintf_fl(NULL, 0, getnanotime() - start,
254 format, ap);
255 va_end(ap);
256}
257
258#else
259
260void trace_printf_key_fl(const char *file, int line, struct trace_key *key,
261 const char *format, ...)
262{
263 va_list ap;
264 va_start(ap, format);
265 trace_vprintf_fl(file, line, key, format, ap);
266 va_end(ap);
267}
268
269void trace_argv_printf_fl(const char *file, int line, const char **argv,
270 const char *format, ...)
271{
272 va_list ap;
273 va_start(ap, format);
274 trace_argv_vprintf_fl(file, line, argv, format, ap);
275 va_end(ap);
276}
277
278void trace_performance_fl(const char *file, int line, uint64_t nanos,
279 const char *format, ...)
280{
281 va_list ap;
282 va_start(ap, format);
283 trace_performance_vprintf_fl(file, line, nanos, format, ap);
284 va_end(ap);
285}
286
287#endif /* HAVE_VARIADIC_MACROS */
288
289
290static const char *quote_crnl(const char *path)
291{
292 static struct strbuf new_path = STRBUF_INIT;
293
294 if (!path)
295 return NULL;
296
297 strbuf_reset(&new_path);
298
299 while (*path) {
300 switch (*path) {
301 case '\\': strbuf_addstr(&new_path, "\\\\"); break;
302 case '\n': strbuf_addstr(&new_path, "\\n"); break;
303 case '\r': strbuf_addstr(&new_path, "\\r"); break;
304 default:
305 strbuf_addch(&new_path, *path);
306 }
307 path++;
308 }
309 return new_path.buf;
310}
311
312/* FIXME: move prefix to startup_info struct and get rid of this arg */
313void trace_repo_setup(const char *prefix)
314{
315 static struct trace_key key = TRACE_KEY_INIT(SETUP);
316 const char *git_work_tree;
317 char *cwd;
318
319 if (!trace_want(&key))
320 return;
321
322 cwd = xgetcwd();
323
324 if (!(git_work_tree = get_git_work_tree()))
325 git_work_tree = "(null)";
326
327 if (!prefix)
328 prefix = "(null)";
329
330 trace_printf_key(&key, "setup: git_dir: %s\n", quote_crnl(get_git_dir()));
331 trace_printf_key(&key, "setup: git_common_dir: %s\n", quote_crnl(get_git_common_dir()));
332 trace_printf_key(&key, "setup: worktree: %s\n", quote_crnl(git_work_tree));
333 trace_printf_key(&key, "setup: cwd: %s\n", quote_crnl(cwd));
334 trace_printf_key(&key, "setup: prefix: %s\n", quote_crnl(prefix));
335
336 free(cwd);
337}
338
339int trace_want(struct trace_key *key)
340{
341 return !!get_trace_fd(key);
342}
343
344#if defined(HAVE_CLOCK_GETTIME) && defined(HAVE_CLOCK_MONOTONIC)
345
346static inline uint64_t highres_nanos(void)
347{
348 struct timespec ts;
349 if (clock_gettime(CLOCK_MONOTONIC, &ts))
350 return 0;
351 return (uint64_t) ts.tv_sec * 1000000000 + ts.tv_nsec;
352}
353
354#elif defined (GIT_WINDOWS_NATIVE)
355
356static inline uint64_t highres_nanos(void)
357{
358 static uint64_t high_ns, scaled_low_ns;
359 static int scale;
360 LARGE_INTEGER cnt;
361
362 if (!scale) {
363 if (!QueryPerformanceFrequency(&cnt))
364 return 0;
365
366 /* high_ns = number of ns per cnt.HighPart */
367 high_ns = (1000000000LL << 32) / (uint64_t) cnt.QuadPart;
368
369 /*
370 * Number of ns per cnt.LowPart is 10^9 / frequency (or
371 * high_ns >> 32). For maximum precision, we scale this factor
372 * so that it just fits within 32 bit (i.e. won't overflow if
373 * multiplied with cnt.LowPart).
374 */
375 scaled_low_ns = high_ns;
376 scale = 32;
377 while (scaled_low_ns >= 0x100000000LL) {
378 scaled_low_ns >>= 1;
379 scale--;
380 }
381 }
382
383 /* if QPF worked on initialization, we expect QPC to work as well */
384 QueryPerformanceCounter(&cnt);
385
386 return (high_ns * cnt.HighPart) +
387 ((scaled_low_ns * cnt.LowPart) >> scale);
388}
389
390#else
391# define highres_nanos() 0
392#endif
393
394static inline uint64_t gettimeofday_nanos(void)
395{
396 struct timeval tv;
397 gettimeofday(&tv, NULL);
398 return (uint64_t) tv.tv_sec * 1000000000 + tv.tv_usec * 1000;
399}
400
401/*
402 * Returns nanoseconds since the epoch (01/01/1970), for performance tracing
403 * (i.e. favoring high precision over wall clock time accuracy).
404 */
405uint64_t getnanotime(void)
406{
407 static uint64_t offset;
408 if (offset > 1) {
409 /* initialization succeeded, return offset + high res time */
410 return offset + highres_nanos();
411 } else if (offset == 1) {
412 /* initialization failed, fall back to gettimeofday */
413 return gettimeofday_nanos();
414 } else {
415 /* initialize offset if high resolution timer works */
416 uint64_t now = gettimeofday_nanos();
417 uint64_t highres = highres_nanos();
418 if (highres)
419 offset = now - highres;
420 else
421 offset = 1;
422 return now;
423 }
424}
425
426static uint64_t command_start_time;
427static struct strbuf command_line = STRBUF_INIT;
428
429static void print_command_performance_atexit(void)
430{
431 trace_performance_since(command_start_time, "git command:%s",
432 command_line.buf);
433}
434
435void trace_command_performance(const char **argv)
436{
437 if (!trace_want(&trace_perf_key))
438 return;
439
440 if (!command_start_time)
441 atexit(print_command_performance_atexit);
442
443 strbuf_reset(&command_line);
444 sq_quote_argv(&command_line, argv, 0);
445 command_start_time = getnanotime();
446}