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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
commit4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f (patch)
tree47c1d492e9c956c1cd2b74dbd3b9d8b0db44dc4e /trace.c
parentInitial commit. (diff)
downloadgit-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.tar.xz
git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.zip
Adding upstream version 1:2.43.0.upstream/1%2.43.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'trace.c')
-rw-r--r--trace.c428
1 files changed, 428 insertions, 0 deletions
diff --git a/trace.c b/trace.c
new file mode 100644
index 0000000..971a68a
--- /dev/null
+++ b/trace.c
@@ -0,0 +1,428 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) 2000-2002 Michael R. Elkins <me@mutt.org>
+ * Copyright (C) 2002-2004 Oswald Buddenhagen <ossi@users.sf.net>
+ * Copyright (C) 2004 Theodore Y. Ts'o <tytso@mit.edu>
+ * Copyright (C) 2006 Mike McCormack
+ * Copyright (C) 2006 Christian Couder
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "git-compat-util.h"
+#include "abspath.h"
+#include "environment.h"
+#include "quote.h"
+#include "setup.h"
+#include "trace.h"
+
+struct trace_key trace_default_key = { "GIT_TRACE", 0, 0, 0 };
+struct trace_key trace_perf_key = TRACE_KEY_INIT(PERFORMANCE);
+struct trace_key trace_setup_key = TRACE_KEY_INIT(SETUP);
+
+/* Get a trace file descriptor from "key" env variable. */
+static int get_trace_fd(struct trace_key *key, const char *override_envvar)
+{
+ const char *trace;
+
+ /* don't open twice */
+ if (key->initialized)
+ return key->fd;
+
+ trace = override_envvar ? override_envvar : getenv(key->key);
+
+ if (!trace || !strcmp(trace, "") ||
+ !strcmp(trace, "0") || !strcasecmp(trace, "false"))
+ key->fd = 0;
+ else if (!strcmp(trace, "1") || !strcasecmp(trace, "true"))
+ key->fd = STDERR_FILENO;
+ else if (strlen(trace) == 1 && isdigit(*trace))
+ key->fd = atoi(trace);
+ else if (is_absolute_path(trace)) {
+ int fd = open(trace, O_WRONLY | O_APPEND | O_CREAT, 0666);
+ if (fd == -1) {
+ warning("could not open '%s' for tracing: %s",
+ trace, strerror(errno));
+ trace_disable(key);
+ } else {
+ key->fd = fd;
+ key->need_close = 1;
+ }
+ } else {
+ warning("unknown trace value for '%s': %s\n"
+ " If you want to trace into a file, then please set %s\n"
+ " to an absolute pathname (starting with /)",
+ key->key, trace, key->key);
+ trace_disable(key);
+ }
+
+ key->initialized = 1;
+ return key->fd;
+}
+
+void trace_override_envvar(struct trace_key *key, const char *value)
+{
+ trace_disable(key);
+ key->initialized = 0;
+
+ /*
+ * Invoke get_trace_fd() to initialize key using the given value
+ * instead of the value of the environment variable.
+ */
+ get_trace_fd(key, value);
+}
+
+void trace_disable(struct trace_key *key)
+{
+ if (key->need_close)
+ close(key->fd);
+ key->fd = 0;
+ key->initialized = 1;
+ key->need_close = 0;
+}
+
+static int prepare_trace_line(const char *file, int line,
+ struct trace_key *key, struct strbuf *buf)
+{
+ static struct trace_key trace_bare = TRACE_KEY_INIT(BARE);
+ struct timeval tv;
+ struct tm tm;
+ time_t secs;
+
+ if (!trace_want(key))
+ return 0;
+
+ /* unit tests may want to disable additional trace output */
+ if (trace_want(&trace_bare))
+ return 1;
+
+ /* print current timestamp */
+ gettimeofday(&tv, NULL);
+ secs = tv.tv_sec;
+ localtime_r(&secs, &tm);
+ strbuf_addf(buf, "%02d:%02d:%02d.%06ld %s:%d", tm.tm_hour, tm.tm_min,
+ tm.tm_sec, (long) tv.tv_usec, file, line);
+ /* align trace output (column 40 catches most files names in git) */
+ while (buf->len < 40)
+ strbuf_addch(buf, ' ');
+
+ return 1;
+}
+
+static void trace_write(struct trace_key *key, const void *buf, unsigned len)
+{
+ if (write_in_full(get_trace_fd(key, NULL), buf, len) < 0) {
+ warning("unable to write trace for %s: %s",
+ key->key, strerror(errno));
+ trace_disable(key);
+ }
+}
+
+void trace_verbatim(struct trace_key *key, const void *buf, unsigned len)
+{
+ if (!trace_want(key))
+ return;
+ trace_write(key, buf, len);
+}
+
+static void print_trace_line(struct trace_key *key, struct strbuf *buf)
+{
+ strbuf_complete_line(buf);
+ trace_write(key, buf->buf, buf->len);
+}
+
+static void trace_vprintf_fl(const char *file, int line, struct trace_key *key,
+ const char *format, va_list ap)
+{
+ struct strbuf buf = STRBUF_INIT;
+
+ if (!prepare_trace_line(file, line, key, &buf))
+ return;
+
+ strbuf_vaddf(&buf, format, ap);
+ print_trace_line(key, &buf);
+ strbuf_release(&buf);
+}
+
+static void trace_argv_vprintf_fl(const char *file, int line,
+ const char **argv, const char *format,
+ va_list ap)
+{
+ struct strbuf buf = STRBUF_INIT;
+
+ if (!prepare_trace_line(file, line, &trace_default_key, &buf))
+ return;
+
+ strbuf_vaddf(&buf, format, ap);
+
+ sq_quote_argv_pretty(&buf, argv);
+ print_trace_line(&trace_default_key, &buf);
+ strbuf_release(&buf);
+}
+
+void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
+ const struct strbuf *data)
+{
+ struct strbuf buf = STRBUF_INIT;
+
+ if (!prepare_trace_line(file, line, key, &buf))
+ return;
+
+ strbuf_addbuf(&buf, data);
+ print_trace_line(key, &buf);
+ strbuf_release(&buf);
+}
+
+static uint64_t perf_start_times[10];
+static int perf_indent;
+
+uint64_t trace_performance_enter(void)
+{
+ uint64_t now;
+
+ if (!trace_want(&trace_perf_key))
+ return 0;
+
+ now = getnanotime();
+ perf_start_times[perf_indent] = now;
+ if (perf_indent + 1 < ARRAY_SIZE(perf_start_times))
+ perf_indent++;
+ else
+ BUG("Too deep indentation");
+ return now;
+}
+
+static void trace_performance_vprintf_fl(const char *file, int line,
+ uint64_t nanos, const char *format,
+ va_list ap)
+{
+ static const char space[] = " ";
+ struct strbuf buf = STRBUF_INIT;
+
+ if (!prepare_trace_line(file, line, &trace_perf_key, &buf))
+ return;
+
+ strbuf_addf(&buf, "performance: %.9f s", (double) nanos / 1000000000);
+
+ if (format && *format) {
+ if (perf_indent >= strlen(space))
+ BUG("Too deep indentation");
+
+ strbuf_addf(&buf, ":%.*s ", perf_indent, space);
+ strbuf_vaddf(&buf, format, ap);
+ }
+
+ print_trace_line(&trace_perf_key, &buf);
+ strbuf_release(&buf);
+}
+
+void trace_printf_key_fl(const char *file, int line, struct trace_key *key,
+ const char *format, ...)
+{
+ va_list ap;
+ va_start(ap, format);
+ trace_vprintf_fl(file, line, key, format, ap);
+ va_end(ap);
+}
+
+void trace_argv_printf_fl(const char *file, int line, const char **argv,
+ const char *format, ...)
+{
+ va_list ap;
+ va_start(ap, format);
+ trace_argv_vprintf_fl(file, line, argv, format, ap);
+ va_end(ap);
+}
+
+void trace_performance_fl(const char *file, int line, uint64_t nanos,
+ const char *format, ...)
+{
+ va_list ap;
+ va_start(ap, format);
+ trace_performance_vprintf_fl(file, line, nanos, format, ap);
+ va_end(ap);
+}
+
+void trace_performance_leave_fl(const char *file, int line,
+ uint64_t nanos, const char *format, ...)
+{
+ va_list ap;
+ uint64_t since;
+
+ if (perf_indent)
+ perf_indent--;
+
+ if (!format) /* Allow callers to leave without tracing anything */
+ return;
+
+ since = perf_start_times[perf_indent];
+ va_start(ap, format);
+ trace_performance_vprintf_fl(file, line, nanos - since, format, ap);
+ va_end(ap);
+}
+
+static const char *quote_crnl(const char *path)
+{
+ static struct strbuf new_path = STRBUF_INIT;
+
+ if (!path)
+ return NULL;
+
+ strbuf_reset(&new_path);
+
+ while (*path) {
+ switch (*path) {
+ case '\\': strbuf_addstr(&new_path, "\\\\"); break;
+ case '\n': strbuf_addstr(&new_path, "\\n"); break;
+ case '\r': strbuf_addstr(&new_path, "\\r"); break;
+ default:
+ strbuf_addch(&new_path, *path);
+ }
+ path++;
+ }
+ return new_path.buf;
+}
+
+void trace_repo_setup(void)
+{
+ const char *git_work_tree, *prefix = startup_info->prefix;
+ char *cwd;
+
+ if (!trace_want(&trace_setup_key))
+ return;
+
+ cwd = xgetcwd();
+
+ if (!(git_work_tree = get_git_work_tree()))
+ git_work_tree = "(null)";
+
+ if (!startup_info->prefix)
+ prefix = "(null)";
+
+ trace_printf_key(&trace_setup_key, "setup: git_dir: %s\n", quote_crnl(get_git_dir()));
+ trace_printf_key(&trace_setup_key, "setup: git_common_dir: %s\n", quote_crnl(get_git_common_dir()));
+ trace_printf_key(&trace_setup_key, "setup: worktree: %s\n", quote_crnl(git_work_tree));
+ trace_printf_key(&trace_setup_key, "setup: cwd: %s\n", quote_crnl(cwd));
+ trace_printf_key(&trace_setup_key, "setup: prefix: %s\n", quote_crnl(prefix));
+
+ free(cwd);
+}
+
+int trace_want(struct trace_key *key)
+{
+ return !!get_trace_fd(key, NULL);
+}
+
+#if defined(HAVE_CLOCK_GETTIME) && defined(HAVE_CLOCK_MONOTONIC)
+
+static inline uint64_t highres_nanos(void)
+{
+ struct timespec ts;
+ if (clock_gettime(CLOCK_MONOTONIC, &ts))
+ return 0;
+ return (uint64_t) ts.tv_sec * 1000000000 + ts.tv_nsec;
+}
+
+#elif defined (GIT_WINDOWS_NATIVE)
+
+static inline uint64_t highres_nanos(void)
+{
+ static uint64_t high_ns, scaled_low_ns;
+ static int scale;
+ LARGE_INTEGER cnt;
+
+ if (!scale) {
+ if (!QueryPerformanceFrequency(&cnt))
+ return 0;
+
+ /* high_ns = number of ns per cnt.HighPart */
+ high_ns = (1000000000LL << 32) / (uint64_t) cnt.QuadPart;
+
+ /*
+ * Number of ns per cnt.LowPart is 10^9 / frequency (or
+ * high_ns >> 32). For maximum precision, we scale this factor
+ * so that it just fits within 32 bit (i.e. won't overflow if
+ * multiplied with cnt.LowPart).
+ */
+ scaled_low_ns = high_ns;
+ scale = 32;
+ while (scaled_low_ns >= 0x100000000LL) {
+ scaled_low_ns >>= 1;
+ scale--;
+ }
+ }
+
+ /* if QPF worked on initialization, we expect QPC to work as well */
+ QueryPerformanceCounter(&cnt);
+
+ return (high_ns * cnt.HighPart) +
+ ((scaled_low_ns * cnt.LowPart) >> scale);
+}
+
+#else
+# define highres_nanos() 0
+#endif
+
+static inline uint64_t gettimeofday_nanos(void)
+{
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ return (uint64_t) tv.tv_sec * 1000000000 + tv.tv_usec * 1000;
+}
+
+/*
+ * Returns nanoseconds since the epoch (01/01/1970), for performance tracing
+ * (i.e. favoring high precision over wall clock time accuracy).
+ */
+uint64_t getnanotime(void)
+{
+ static uint64_t offset;
+ if (offset > 1) {
+ /* initialization succeeded, return offset + high res time */
+ return offset + highres_nanos();
+ } else if (offset == 1) {
+ /* initialization failed, fall back to gettimeofday */
+ return gettimeofday_nanos();
+ } else {
+ /* initialize offset if high resolution timer works */
+ uint64_t now = gettimeofday_nanos();
+ uint64_t highres = highres_nanos();
+ if (highres)
+ offset = now - highres;
+ else
+ offset = 1;
+ return now;
+ }
+}
+
+static struct strbuf command_line = STRBUF_INIT;
+
+static void print_command_performance_atexit(void)
+{
+ trace_performance_leave("git command:%s", command_line.buf);
+}
+
+void trace_command_performance(const char **argv)
+{
+ if (!trace_want(&trace_perf_key))
+ return;
+
+ if (!command_line.len)
+ atexit(print_command_performance_atexit);
+
+ strbuf_reset(&command_line);
+ sq_quote_argv_pretty(&command_line, argv);
+ trace_performance_enter();
+}