@matheusbsbs / matheus-bagliano / commits / 9720d23e8c

date: make DATE_MODE thread-safe

date_mode_from_type() modifies a static variable and returns a pointer to it. This is not thread-safe. Most callers of date_mode_from_type() use it via the macro DATE_MODE and pass its result on to functions like show_date(), which take a const pointer and don't modify the struct. Avoid the static storage by putting the variable on the stack and returning the whole struct date_mode. Change functions that take a constant pointer to expect the whole struct instead. Reduce the cost of passing struct date_mode around on 64-bit systems by reordering its members to close the hole between the 32-bit wide .type and the 64-bit aligned .strftime_fmt as well as the alignment hole at the end. sizeof reports 24 before and 16 with this change on x64. Keep .type at the top to still allow initialization without designator -- though that's only done in a single location, in builtin/blame.c. Signed-off-by: René Scharfe <l.s.r@web.de> Acked-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

René Scharfe committed Apr 5, 2024 at 19:44 UTC 9720d23e8caf4adee44b3a32803a9bb0480118bd
12 files changed +44 -44
builtin/blame.c
+2 -2
@@ -316,7 +316,7 @@ static const char *format_time(timestamp_t time, const char *tz_str,
316 size_t time_width;
317 int tz;
318 tz = atoi(tz_str);
319 - time_str = show_date(time, tz, &blame_date_mode);
319 + time_str = show_date(time, tz, blame_date_mode);
320 strbuf_addstr(&time_buf, time_str);
321 /*
322 * Add space paddings to time_buf to display a fixed width
@@ -1029,7 +1029,7 @@ parse_done:
1029 blame_date_width = sizeof("Thu Oct 19 16:00:04 2006 -0700");
1030 break;
1031 case DATE_STRFTIME:
1032 - blame_date_width = strlen(show_date(0, 0, &blame_date_mode)) + 1; /* add the null */
1032 + blame_date_width = strlen(show_date(0, 0, blame_date_mode)) + 1; /* add the null */
1033 break;
1034 }
1035 blame_date_width -= 1; /* strip the null */
date.c
+18 -18
@@ -207,13 +207,13 @@ void show_date_relative(timestamp_t time, struct strbuf *timebuf)
207 (diff + 183) / 365);
208 }
209
210 -struct date_mode *date_mode_from_type(enum date_mode_type type)
210 +struct date_mode date_mode_from_type(enum date_mode_type type)
211 {
212 - static struct date_mode mode = DATE_MODE_INIT;
212 + struct date_mode mode = DATE_MODE_INIT;
213 if (type == DATE_STRFTIME)
214 BUG("cannot create anonymous strftime date_mode struct");
215 mode.type = type;
216 - return &mode;
216 + return mode;
217 }
218
219 static void show_date_normal(struct strbuf *buf, timestamp_t time, struct tm *tm, int tz, struct tm *human_tm, int human_tz, int local)
@@ -283,7 +283,7 @@ static void show_date_normal(struct strbuf *buf, timestamp_t time, struct tm *tm
283 strbuf_addf(buf, " %+05d", tz);
284 }
285
286 -const char *show_date(timestamp_t time, int tz, const struct date_mode *mode)
286 +const char *show_date(timestamp_t time, int tz, struct date_mode mode)
287 {
288 struct tm *tm;
289 struct tm tmbuf = { 0 };
@@ -291,13 +291,13 @@ const char *show_date(timestamp_t time, int tz, const struct date_mode *mode)
291 int human_tz = -1;
292 static struct strbuf timebuf = STRBUF_INIT;
293
294 - if (mode->type == DATE_UNIX) {
294 + if (mode.type == DATE_UNIX) {
295 strbuf_reset(&timebuf);
296 strbuf_addf(&timebuf, "%"PRItime, time);
297 return timebuf.buf;
298 }
299
300 - if (mode->type == DATE_HUMAN) {
300 + if (mode.type == DATE_HUMAN) {
301 struct timeval now;
302
303 get_time(&now);
@@ -306,22 +306,22 @@ const char *show_date(timestamp_t time, int tz, const struct date_mode *mode)
306 human_tz = local_time_tzoffset(now.tv_sec, &human_tm);
307 }
308
309 - if (mode->local)
309 + if (mode.local)
310 tz = local_tzoffset(time);
311
312 - if (mode->type == DATE_RAW) {
312 + if (mode.type == DATE_RAW) {
313 strbuf_reset(&timebuf);
314 strbuf_addf(&timebuf, "%"PRItime" %+05d", time, tz);
315 return timebuf.buf;
316 }
317
318 - if (mode->type == DATE_RELATIVE) {
318 + if (mode.type == DATE_RELATIVE) {
319 strbuf_reset(&timebuf);
320 show_date_relative(time, &timebuf);
321 return timebuf.buf;
322 }
323
324 - if (mode->local)
324 + if (mode.local)
325 tm = time_to_tm_local(time, &tmbuf);
326 else
327 tm = time_to_tm(time, tz, &tmbuf);
@@ -331,17 +331,17 @@ const char *show_date(timestamp_t time, int tz, const struct date_mode *mode)
331 }
332
333 strbuf_reset(&timebuf);
334 - if (mode->type == DATE_SHORT)
334 + if (mode.type == DATE_SHORT)
335 strbuf_addf(&timebuf, "%04d-%02d-%02d", tm->tm_year + 1900,
336 tm->tm_mon + 1, tm->tm_mday);
337 - else if (mode->type == DATE_ISO8601)
337 + else if (mode.type == DATE_ISO8601)
338 strbuf_addf(&timebuf, "%04d-%02d-%02d %02d:%02d:%02d %+05d",
339 tm->tm_year + 1900,
340 tm->tm_mon + 1,
341 tm->tm_mday,
342 tm->tm_hour, tm->tm_min, tm->tm_sec,
343 tz);
344 - else if (mode->type == DATE_ISO8601_STRICT) {
344 + else if (mode.type == DATE_ISO8601_STRICT) {
345 strbuf_addf(&timebuf, "%04d-%02d-%02dT%02d:%02d:%02d",
346 tm->tm_year + 1900,
347 tm->tm_mon + 1,
@@ -354,16 +354,16 @@ const char *show_date(timestamp_t time, int tz, const struct date_mode *mode)
354 tz = abs(tz);
355 strbuf_addf(&timebuf, "%02d:%02d", tz / 100, tz % 100);
356 }
357 - } else if (mode->type == DATE_RFC2822)
357 + } else if (mode.type == DATE_RFC2822)
358 strbuf_addf(&timebuf, "%.3s, %d %.3s %d %02d:%02d:%02d %+05d",
359 weekday_names[tm->tm_wday], tm->tm_mday,
360 month_names[tm->tm_mon], tm->tm_year + 1900,
361 tm->tm_hour, tm->tm_min, tm->tm_sec, tz);
362 - else if (mode->type == DATE_STRFTIME)
363 - strbuf_addftime(&timebuf, mode->strftime_fmt, tm, tz,
364 - !mode->local);
362 + else if (mode.type == DATE_STRFTIME)
363 + strbuf_addftime(&timebuf, mode.strftime_fmt, tm, tz,
364 + !mode.local);
365 else
366 - show_date_normal(&timebuf, time, tm, tz, &human_tm, human_tz, mode->local);
366 + show_date_normal(&timebuf, time, tm, tz, &human_tm, human_tz, mode.local);
367 return timebuf.buf;
368 }
369
date.h
+3 -3
@@ -22,8 +22,8 @@ enum date_mode_type {
22
23 struct date_mode {
24 enum date_mode_type type;
25 - const char *strftime_fmt;
25 int local;
26 + const char *strftime_fmt;
27 };
28
29 #define DATE_MODE_INIT { \
@@ -36,14 +36,14 @@ struct date_mode {
36 * show_date(t, tz, DATE_MODE(NORMAL));
37 */
38 #define DATE_MODE(t) date_mode_from_type(DATE_##t)
39 -struct date_mode *date_mode_from_type(enum date_mode_type type);
39 +struct date_mode date_mode_from_type(enum date_mode_type type);
40
41 /**
42 * Format <'time', 'timezone'> into static memory according to 'mode'
43 * and return it. The mode is an initialized "struct date_mode"
44 * (usually from the DATE_MODE() macro).
45 */
46 -const char *show_date(timestamp_t time, int timezone, const struct date_mode *mode);
46 +const char *show_date(timestamp_t time, int timezone, struct date_mode mode);
47
48 /**
49 * Parse a date format for later use with show_date().
gpg-interface.c
+1 -1
@@ -483,7 +483,7 @@ static int verify_ssh_signed_buffer(struct signature_check *sigc,
483
484 if (sigc->payload_timestamp)
485 strbuf_addf(&verify_time, "-Overify-time=%s",
486 - show_date(sigc->payload_timestamp, 0, &verify_date_mode));
486 + show_date(sigc->payload_timestamp, 0, verify_date_mode));
487
488 /* Find the principal from the signers */
489 strvec_pushl(&ssh_keygen.args, fmt->program,
log-tree.c
+1 -1
@@ -777,7 +777,7 @@ void show_log(struct rev_info *opt)
777 */
778 show_reflog_message(opt->reflog_info,
779 opt->commit_format == CMIT_FMT_ONELINE,
780 - &opt->date_mode,
780 + opt->date_mode,
781 opt->date_mode_explicit);
782 if (opt->commit_format == CMIT_FMT_ONELINE)
783 return;
oss-fuzz/fuzz-date.c
+3 -3
@@ -11,7 +11,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
11 int16_t tz;
12 timestamp_t ts;
13 enum date_mode_type dmtype;
14 - struct date_mode *dm;
14 + struct date_mode dm;
15
16 if (size <= 4)
17 /*
@@ -40,10 +40,10 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
40 free(str);
41
42 dm = date_mode_from_type(dmtype);
43 - dm->local = local;
43 + dm.local = local;
44 show_date(ts, (int)tz, dm);
45
46 - date_mode_release(dm);
46 + date_mode_release(&dm);
47
48 return 0;
49 }
pretty.c
+9 -9
@@ -428,7 +428,7 @@ static void add_rfc2047(struct strbuf *sb, const char *line, size_t len,
428 }
429
430 const char *show_ident_date(const struct ident_split *ident,
431 - const struct date_mode *mode)
431 + struct date_mode mode)
432 {
433 timestamp_t date = 0;
434 long tz = 0;
@@ -592,7 +592,7 @@ void pp_user_info(struct pretty_print_context *pp,
592 switch (pp->fmt) {
593 case CMIT_FMT_MEDIUM:
594 strbuf_addf(sb, "Date: %s\n",
595 - show_ident_date(&ident, &pp->date_mode));
595 + show_ident_date(&ident, pp->date_mode));
596 break;
597 case CMIT_FMT_EMAIL:
598 case CMIT_FMT_MBOXRD:
@@ -601,7 +601,7 @@ void pp_user_info(struct pretty_print_context *pp,
601 break;
602 case CMIT_FMT_FULLER:
603 strbuf_addf(sb, "%sDate: %s\n", what,
604 - show_ident_date(&ident, &pp->date_mode));
604 + show_ident_date(&ident, pp->date_mode));
605 break;
606 default:
607 /* notin' */
@@ -775,7 +775,7 @@ static int mailmap_name(const char **email, size_t *email_len,
775
776 static size_t format_person_part(struct strbuf *sb, char part,
777 const char *msg, int len,
778 - const struct date_mode *dmode)
778 + struct date_mode dmode)
779 {
780 /* currently all placeholders have same length */
781 const int placeholder_len = 2;
@@ -1034,7 +1034,7 @@ static void rewrap_message_tail(struct strbuf *sb,
1034 static int format_reflog_person(struct strbuf *sb,
1035 char part,
1036 struct reflog_walk_info *log,
1037 - const struct date_mode *dmode)
1037 + struct date_mode dmode)
1038 {
1039 const char *ident;
1040
@@ -1602,7 +1602,7 @@ static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
1602 if (c->pretty_ctx->reflog_info)
1603 get_reflog_selector(sb,
1604 c->pretty_ctx->reflog_info,
1605 - &c->pretty_ctx->date_mode,
1605 + c->pretty_ctx->date_mode,
1606 c->pretty_ctx->date_mode_explicit,
1607 (placeholder[1] == 'd'));
1608 return 2;
@@ -1617,7 +1617,7 @@ static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
1617 return format_reflog_person(sb,
1618 placeholder[1],
1619 c->pretty_ctx->reflog_info,
1620 - &c->pretty_ctx->date_mode);
1620 + c->pretty_ctx->date_mode);
1621 }
1622 return 0; /* unknown %g placeholder */
1623 case 'N':
@@ -1712,11 +1712,11 @@ static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
1712 case 'a': /* author ... */
1713 return format_person_part(sb, placeholder[1],
1714 msg + c->author.off, c->author.len,
1715 - &c->pretty_ctx->date_mode);
1715 + c->pretty_ctx->date_mode);
1716 case 'c': /* committer ... */
1717 return format_person_part(sb, placeholder[1],
1718 msg + c->committer.off, c->committer.len,
1719 - &c->pretty_ctx->date_mode);
1719 + c->pretty_ctx->date_mode);
1720 case 'e': /* encoding */
1721 if (c->commit_encoding)
1722 strbuf_addstr(sb, c->commit_encoding);
pretty.h
+1 -1
@@ -168,7 +168,7 @@ int format_set_trailers_options(struct process_trailer_options *opts,
168 * a well-known sentinel date if they appear bogus.
169 */
170 const char *show_ident_date(const struct ident_split *id,
171 - const struct date_mode *mode);
171 + struct date_mode mode);
172
173
174 #endif /* PRETTY_H */
ref-filter.c
+1 -1
@@ -1627,7 +1627,7 @@ static void grab_date(const char *buf, struct atom_value *v, const char *atomnam
1627 tz = strtol(zone, NULL, 10);
1628 if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
1629 goto bad;
1630 - v->s = xstrdup(show_date(timestamp, tz, &date_mode));
1630 + v->s = xstrdup(show_date(timestamp, tz, date_mode));
1631 v->value = timestamp;
1632 date_mode_release(&date_mode);
1633 return;
reflog-walk.c
+2 -2
@@ -223,7 +223,7 @@ int add_reflog_for_walk(struct reflog_walk_info *info,
223
224 void get_reflog_selector(struct strbuf *sb,
225 struct reflog_walk_info *reflog_info,
226 - const struct date_mode *dmode, int force_date,
226 + struct date_mode dmode, int force_date,
227 int shorten)
228 {
229 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
@@ -297,7 +297,7 @@ timestamp_t get_reflog_timestamp(struct reflog_walk_info *reflog_info)
297 }
298
299 void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,
300 - const struct date_mode *dmode, int force_date)
300 + struct date_mode dmode, int force_date)
301 {
302 if (reflog_info && reflog_info->last_commit_reflog) {
303 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
reflog-walk.h
+2 -2
@@ -10,14 +10,14 @@ void reflog_walk_info_release(struct reflog_walk_info *info);
10 int add_reflog_for_walk(struct reflog_walk_info *info,
11 struct commit *commit, const char *name);
12 void show_reflog_message(struct reflog_walk_info *info, int,
13 - const struct date_mode *, int force_date);
13 + struct date_mode, int force_date);
14 void get_reflog_message(struct strbuf *sb,
15 struct reflog_walk_info *reflog_info);
16 const char *get_reflog_ident(struct reflog_walk_info *reflog_info);
17 timestamp_t get_reflog_timestamp(struct reflog_walk_info *reflog_info);
18 void get_reflog_selector(struct strbuf *sb,
19 struct reflog_walk_info *reflog_info,
20 - const struct date_mode *dmode, int force_date,
20 + struct date_mode dmode, int force_date,
21 int shorten);
22
23 int reflog_walk_empty(struct reflog_walk_info *walk);
t/helper/test-date.c
+1 -1
@@ -52,7 +52,7 @@ static void show_dates(const char **argv, const char *format)
52 arg++;
53 tz = atoi(arg);
54
55 - printf("%s -> %s\n", *argv, show_date(t, tz, &mode));
55 + printf("%s -> %s\n", *argv, show_date(t, tz, mode));
56 }
57
58 date_mode_release(&mode);