trace.con commit test-hashmap: use xsnprintf rather than snprintf (cbadf0e)
   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, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24#include "cache.h"
  25#include "quote.h"
  26
  27/*
  28 * "Normalize" a key argument by converting NULL to our trace_default,
  29 * and otherwise passing through the value. All caller-facing functions
  30 * should normalize their inputs in this way, though most get it
  31 * for free by calling get_trace_fd() (directly or indirectly).
  32 */
  33static void normalize_trace_key(struct trace_key **key)
  34{
  35        static struct trace_key trace_default = { "GIT_TRACE" };
  36        if (!*key)
  37                *key = &trace_default;
  38}
  39
  40/* Get a trace file descriptor from "key" env variable. */
  41static int get_trace_fd(struct trace_key *key)
  42{
  43        const char *trace;
  44
  45        normalize_trace_key(&key);
  46
  47        /* don't open twice */
  48        if (key->initialized)
  49                return key->fd;
  50
  51        trace = getenv(key->key);
  52
  53        if (!trace || !strcmp(trace, "") ||
  54            !strcmp(trace, "0") || !strcasecmp(trace, "false"))
  55                key->fd = 0;
  56        else if (!strcmp(trace, "1") || !strcasecmp(trace, "true"))
  57                key->fd = STDERR_FILENO;
  58        else if (strlen(trace) == 1 && isdigit(*trace))
  59                key->fd = atoi(trace);
  60        else if (is_absolute_path(trace)) {
  61                int fd = open(trace, O_WRONLY | O_APPEND | O_CREAT, 0666);
  62                if (fd == -1) {
  63                        warning("could not open '%s' for tracing: %s",
  64                                trace, strerror(errno));
  65                        trace_disable(key);
  66                } else {
  67                        key->fd = fd;
  68                        key->need_close = 1;
  69                }
  70        } else {
  71                warning("unknown trace value for '%s': %s\n"
  72                        "         If you want to trace into a file, then please set %s\n"
  73                        "         to an absolute pathname (starting with /)",
  74                        key->key, trace, key->key);
  75                trace_disable(key);
  76        }
  77
  78        key->initialized = 1;
  79        return key->fd;
  80}
  81
  82void trace_disable(struct trace_key *key)
  83{
  84        normalize_trace_key(&key);
  85
  86        if (key->need_close)
  87                close(key->fd);
  88        key->fd = 0;
  89        key->initialized = 1;
  90        key->need_close = 0;
  91}
  92
  93static int prepare_trace_line(const char *file, int line,
  94                              struct trace_key *key, struct strbuf *buf)
  95{
  96        static struct trace_key trace_bare = TRACE_KEY_INIT(BARE);
  97        struct timeval tv;
  98        struct tm tm;
  99        time_t secs;
 100
 101        if (!trace_want(key))
 102                return 0;
 103
 104        set_try_to_free_routine(NULL);  /* is never reset */
 105
 106        /* unit tests may want to disable additional trace output */
 107        if (trace_want(&trace_bare))
 108                return 1;
 109
 110        /* print current timestamp */
 111        gettimeofday(&tv, NULL);
 112        secs = tv.tv_sec;
 113        localtime_r(&secs, &tm);
 114        strbuf_addf(buf, "%02d:%02d:%02d.%06ld ", tm.tm_hour, tm.tm_min,
 115                    tm.tm_sec, (long) tv.tv_usec);
 116
 117#ifdef HAVE_VARIADIC_MACROS
 118        /* print file:line */
 119        strbuf_addf(buf, "%s:%d ", file, line);
 120        /* align trace output (column 40 catches most files names in git) */
 121        while (buf->len < 40)
 122                strbuf_addch(buf, ' ');
 123#endif
 124
 125        return 1;
 126}
 127
 128static void trace_write(struct trace_key *key, const void *buf, unsigned len)
 129{
 130        if (write_in_full(get_trace_fd(key), buf, len) < 0) {
 131                normalize_trace_key(&key);
 132                warning("unable to write trace for %s: %s",
 133                        key->key, strerror(errno));
 134                trace_disable(key);
 135        }
 136}
 137
 138void trace_verbatim(struct trace_key *key, const void *buf, unsigned len)
 139{
 140        if (!trace_want(key))
 141                return;
 142        trace_write(key, buf, len);
 143}
 144
 145static void print_trace_line(struct trace_key *key, struct strbuf *buf)
 146{
 147        strbuf_complete_line(buf);
 148        trace_write(key, buf->buf, buf->len);
 149        strbuf_release(buf);
 150}
 151
 152static void trace_vprintf_fl(const char *file, int line, struct trace_key *key,
 153                             const char *format, va_list ap)
 154{
 155        struct strbuf buf = STRBUF_INIT;
 156
 157        if (!prepare_trace_line(file, line, key, &buf))
 158                return;
 159
 160        strbuf_vaddf(&buf, format, ap);
 161        print_trace_line(key, &buf);
 162}
 163
 164static void trace_argv_vprintf_fl(const char *file, int line,
 165                                  const char **argv, const char *format,
 166                                  va_list ap)
 167{
 168        struct strbuf buf = STRBUF_INIT;
 169
 170        if (!prepare_trace_line(file, line, NULL, &buf))
 171                return;
 172
 173        strbuf_vaddf(&buf, format, ap);
 174
 175        sq_quote_argv(&buf, argv, 0);
 176        print_trace_line(NULL, &buf);
 177}
 178
 179void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
 180                     const struct strbuf *data)
 181{
 182        struct strbuf buf = STRBUF_INIT;
 183
 184        if (!prepare_trace_line(file, line, key, &buf))
 185                return;
 186
 187        strbuf_addbuf(&buf, data);
 188        print_trace_line(key, &buf);
 189}
 190
 191static struct trace_key trace_perf_key = TRACE_KEY_INIT(PERFORMANCE);
 192
 193static void trace_performance_vprintf_fl(const char *file, int line,
 194                                         uint64_t nanos, const char *format,
 195                                         va_list ap)
 196{
 197        struct strbuf buf = STRBUF_INIT;
 198
 199        if (!prepare_trace_line(file, line, &trace_perf_key, &buf))
 200                return;
 201
 202        strbuf_addf(&buf, "performance: %.9f s", (double) nanos / 1000000000);
 203
 204        if (format && *format) {
 205                strbuf_addstr(&buf, ": ");
 206                strbuf_vaddf(&buf, format, ap);
 207        }
 208
 209        print_trace_line(&trace_perf_key, &buf);
 210}
 211
 212#ifndef HAVE_VARIADIC_MACROS
 213
 214void trace_printf(const char *format, ...)
 215{
 216        va_list ap;
 217        va_start(ap, format);
 218        trace_vprintf_fl(NULL, 0, NULL, format, ap);
 219        va_end(ap);
 220}
 221
 222void trace_printf_key(struct trace_key *key, const char *format, ...)
 223{
 224        va_list ap;
 225        va_start(ap, format);
 226        trace_vprintf_fl(NULL, 0, key, format, ap);
 227        va_end(ap);
 228}
 229
 230void trace_argv_printf(const char **argv, const char *format, ...)
 231{
 232        va_list ap;
 233        va_start(ap, format);
 234        trace_argv_vprintf_fl(NULL, 0, argv, format, ap);
 235        va_end(ap);
 236}
 237
 238void trace_strbuf(struct trace_key *key, const struct strbuf *data)
 239{
 240        trace_strbuf_fl(NULL, 0, key, data);
 241}
 242
 243void trace_performance(uint64_t nanos, const char *format, ...)
 244{
 245        va_list ap;
 246        va_start(ap, format);
 247        trace_performance_vprintf_fl(NULL, 0, nanos, format, ap);
 248        va_end(ap);
 249}
 250
 251void trace_performance_since(uint64_t start, const char *format, ...)
 252{
 253        va_list ap;
 254        va_start(ap, format);
 255        trace_performance_vprintf_fl(NULL, 0, getnanotime() - start,
 256                                     format, ap);
 257        va_end(ap);
 258}
 259
 260#else
 261
 262void trace_printf_key_fl(const char *file, int line, struct trace_key *key,
 263                         const char *format, ...)
 264{
 265        va_list ap;
 266        va_start(ap, format);
 267        trace_vprintf_fl(file, line, key, format, ap);
 268        va_end(ap);
 269}
 270
 271void trace_argv_printf_fl(const char *file, int line, const char **argv,
 272                          const char *format, ...)
 273{
 274        va_list ap;
 275        va_start(ap, format);
 276        trace_argv_vprintf_fl(file, line, argv, format, ap);
 277        va_end(ap);
 278}
 279
 280void trace_performance_fl(const char *file, int line, uint64_t nanos,
 281                              const char *format, ...)
 282{
 283        va_list ap;
 284        va_start(ap, format);
 285        trace_performance_vprintf_fl(file, line, nanos, format, ap);
 286        va_end(ap);
 287}
 288
 289#endif /* HAVE_VARIADIC_MACROS */
 290
 291
 292static const char *quote_crnl(const char *path)
 293{
 294        static struct strbuf new_path = STRBUF_INIT;
 295
 296        if (!path)
 297                return NULL;
 298
 299        strbuf_reset(&new_path);
 300
 301        while (*path) {
 302                switch (*path) {
 303                case '\\': strbuf_addstr(&new_path, "\\\\"); break;
 304                case '\n': strbuf_addstr(&new_path, "\\n"); break;
 305                case '\r': strbuf_addstr(&new_path, "\\r"); break;
 306                default:
 307                        strbuf_addch(&new_path, *path);
 308                }
 309                path++;
 310        }
 311        return new_path.buf;
 312}
 313
 314/* FIXME: move prefix to startup_info struct and get rid of this arg */
 315void trace_repo_setup(const char *prefix)
 316{
 317        static struct trace_key key = TRACE_KEY_INIT(SETUP);
 318        const char *git_work_tree;
 319        char *cwd;
 320
 321        if (!trace_want(&key))
 322                return;
 323
 324        cwd = xgetcwd();
 325
 326        if (!(git_work_tree = get_git_work_tree()))
 327                git_work_tree = "(null)";
 328
 329        if (!prefix)
 330                prefix = "(null)";
 331
 332        trace_printf_key(&key, "setup: git_dir: %s\n", quote_crnl(get_git_dir()));
 333        trace_printf_key(&key, "setup: git_common_dir: %s\n", quote_crnl(get_git_common_dir()));
 334        trace_printf_key(&key, "setup: worktree: %s\n", quote_crnl(git_work_tree));
 335        trace_printf_key(&key, "setup: cwd: %s\n", quote_crnl(cwd));
 336        trace_printf_key(&key, "setup: prefix: %s\n", quote_crnl(prefix));
 337
 338        free(cwd);
 339}
 340
 341int trace_want(struct trace_key *key)
 342{
 343        return !!get_trace_fd(key);
 344}
 345
 346#if defined(HAVE_CLOCK_GETTIME) && defined(HAVE_CLOCK_MONOTONIC)
 347
 348static inline uint64_t highres_nanos(void)
 349{
 350        struct timespec ts;
 351        if (clock_gettime(CLOCK_MONOTONIC, &ts))
 352                return 0;
 353        return (uint64_t) ts.tv_sec * 1000000000 + ts.tv_nsec;
 354}
 355
 356#elif defined (GIT_WINDOWS_NATIVE)
 357
 358static inline uint64_t highres_nanos(void)
 359{
 360        static uint64_t high_ns, scaled_low_ns;
 361        static int scale;
 362        LARGE_INTEGER cnt;
 363
 364        if (!scale) {
 365                if (!QueryPerformanceFrequency(&cnt))
 366                        return 0;
 367
 368                /* high_ns = number of ns per cnt.HighPart */
 369                high_ns = (1000000000LL << 32) / (uint64_t) cnt.QuadPart;
 370
 371                /*
 372                 * Number of ns per cnt.LowPart is 10^9 / frequency (or
 373                 * high_ns >> 32). For maximum precision, we scale this factor
 374                 * so that it just fits within 32 bit (i.e. won't overflow if
 375                 * multiplied with cnt.LowPart).
 376                 */
 377                scaled_low_ns = high_ns;
 378                scale = 32;
 379                while (scaled_low_ns >= 0x100000000LL) {
 380                        scaled_low_ns >>= 1;
 381                        scale--;
 382                }
 383        }
 384
 385        /* if QPF worked on initialization, we expect QPC to work as well */
 386        QueryPerformanceCounter(&cnt);
 387
 388        return (high_ns * cnt.HighPart) +
 389               ((scaled_low_ns * cnt.LowPart) >> scale);
 390}
 391
 392#else
 393# define highres_nanos() 0
 394#endif
 395
 396static inline uint64_t gettimeofday_nanos(void)
 397{
 398        struct timeval tv;
 399        gettimeofday(&tv, NULL);
 400        return (uint64_t) tv.tv_sec * 1000000000 + tv.tv_usec * 1000;
 401}
 402
 403/*
 404 * Returns nanoseconds since the epoch (01/01/1970), for performance tracing
 405 * (i.e. favoring high precision over wall clock time accuracy).
 406 */
 407uint64_t getnanotime(void)
 408{
 409        static uint64_t offset;
 410        if (offset > 1) {
 411                /* initialization succeeded, return offset + high res time */
 412                return offset + highres_nanos();
 413        } else if (offset == 1) {
 414                /* initialization failed, fall back to gettimeofday */
 415                return gettimeofday_nanos();
 416        } else {
 417                /* initialize offset if high resolution timer works */
 418                uint64_t now = gettimeofday_nanos();
 419                uint64_t highres = highres_nanos();
 420                if (highres)
 421                        offset = now - highres;
 422                else
 423                        offset = 1;
 424                return now;
 425        }
 426}
 427
 428static uint64_t command_start_time;
 429static struct strbuf command_line = STRBUF_INIT;
 430
 431static void print_command_performance_atexit(void)
 432{
 433        trace_performance_since(command_start_time, "git command:%s",
 434                                command_line.buf);
 435}
 436
 437void trace_command_performance(const char **argv)
 438{
 439        if (!trace_want(&trace_perf_key))
 440                return;
 441
 442        if (!command_start_time)
 443                atexit(print_command_performance_atexit);
 444
 445        strbuf_reset(&command_line);
 446        sq_quote_argv(&command_line, argv, 0);
 447        command_start_time = getnanotime();
 448}