[PATCH v6 5/8] Introduce a new "printf format" for timestamps

[Johannes Schindelin <johannes.schindelin@gmx.de>]

Currently, Git's source code treats all timestamps as if they were
unsigned longs. Therefore, it is okay to write "%lu" when printing them.

There is a substantial problem with that, though: at least on Windows,
time_t is *larger* than unsigned long, and hence we will want to switch
away from the ill-specified `unsigned long` data type.

So let's introduce the pseudo format "PRItime" (currently simply being
defined to "lu") to make it easier to change the data type used for
timestamps.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/blame.c               |  6 +++---
 builtin/fsck.c                |  2 +-
 builtin/log.c                 |  2 +-
 builtin/receive-pack.c        |  4 ++--
 builtin/rev-list.c            |  2 +-
 builtin/rev-parse.c           |  2 +-
 date.c                        | 26 +++++++++++++-------------
 fetch-pack.c                  |  2 +-
 git-compat-util.h             |  1 +
 refs/files-backend.c          |  2 +-
 t/helper/test-date.c          |  2 +-
 t/helper/test-parse-options.c |  2 +-
 t/helper/test-ref-store.c     |  2 +-
 upload-pack.c                 |  2 +-
 vcs-svn/fast_export.c         |  4 ++--
 15 files changed, 31 insertions(+), 30 deletions(-)

diff --git a/builtin/blame.c b/builtin/blame.c
index 07506a3e457..e4b3c7b0ebf 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -1727,11 +1727,11 @@ static int emit_one_suspect_detail(struct origin *suspect, int repeat)
 	get_commit_info(suspect->commit, &ci, 1);
 	printf("author %s\n", ci.author.buf);
 	printf("author-mail %s\n", ci.author_mail.buf);
-	printf("author-time %lu\n", ci.author_time);
+	printf("author-time %"PRItime"\n", ci.author_time);
 	printf("author-tz %s\n", ci.author_tz.buf);
 	printf("committer %s\n", ci.committer.buf);
 	printf("committer-mail %s\n", ci.committer_mail.buf);
-	printf("committer-time %lu\n", ci.committer_time);
+	printf("committer-time %"PRItime"\n", ci.committer_time);
 	printf("committer-tz %s\n", ci.committer_tz.buf);
 	printf("summary %s\n", ci.summary.buf);
 	if (suspect->commit->object.flags & UNINTERESTING)
@@ -1844,7 +1844,7 @@ static const char *format_time(unsigned long time, const char *tz_str,
 
 	strbuf_reset(&time_buf);
 	if (show_raw_time) {
-		strbuf_addf(&time_buf, "%lu %s", time, tz_str);
+		strbuf_addf(&time_buf, "%"PRItime" %s", time, tz_str);
 	}
 	else {
 		const char *time_str;
diff --git a/builtin/fsck.c b/builtin/fsck.c
index b5e13a45560..c233eda21c8 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -407,7 +407,7 @@ static void fsck_handle_reflog_oid(const char *refname, struct object_id *oid,
 			if (timestamp && name_objects)
 				add_decoration(fsck_walk_options.object_names,
 					obj,
-					xstrfmt("%s@{%ld}", refname, timestamp));
+					xstrfmt("%s@{%"PRItime"}", refname, timestamp));
 			obj->used = 1;
 			mark_object_reachable(obj);
 		} else {
diff --git a/builtin/log.c b/builtin/log.c
index b3b10cc1edb..f93ef6c7100 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -910,7 +910,7 @@ static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids)
 static void gen_message_id(struct rev_info *info, char *base)
 {
 	struct strbuf buf = STRBUF_INIT;
-	strbuf_addf(&buf, "%s.%lu.git.%s", base,
+	strbuf_addf(&buf, "%s.%"PRItime".git.%s", base,
 		    (unsigned long) time(NULL),
 		    git_committer_info(IDENT_NO_NAME|IDENT_NO_DATE|IDENT_STRICT));
 	info->message_id = strbuf_detach(&buf, NULL);
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index d25a57931f8..ab718f4402c 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -459,12 +459,12 @@ static char *prepare_push_cert_nonce(const char *path, unsigned long stamp)
 	struct strbuf buf = STRBUF_INIT;
 	unsigned char sha1[20];
 
-	strbuf_addf(&buf, "%s:%lu", path, stamp);
+	strbuf_addf(&buf, "%s:%"PRItime, path, stamp);
 	hmac_sha1(sha1, buf.buf, buf.len, cert_nonce_seed, strlen(cert_nonce_seed));;
 	strbuf_release(&buf);
 
 	/* RFC 2104 5. HMAC-SHA1-80 */
-	strbuf_addf(&buf, "%lu-%.*s", stamp, 20, sha1_to_hex(sha1));
+	strbuf_addf(&buf, "%"PRItime"-%.*s", stamp, 20, sha1_to_hex(sha1));
 	return strbuf_detach(&buf, NULL);
 }
 
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index bcf77f0b8a2..3b292c99bda 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -80,7 +80,7 @@ static void show_commit(struct commit *commit, void *data)
 	}
 
 	if (info->show_timestamp)
-		printf("%lu ", commit->date);
+		printf("%"PRItime" ", commit->date);
 	if (info->header_prefix)
 		fputs(info->header_prefix, stdout);
 
diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index 05133309106..b4509002435 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c
@@ -218,7 +218,7 @@ static void show_datestring(const char *flag, const char *datestr)
 	/* date handling requires both flags and revs */
 	if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
 		return;
-	buffer = xstrfmt("%s%lu", flag, approxidate(datestr));
+	buffer = xstrfmt("%s%"PRItime, flag, approxidate(datestr));
 	show(buffer);
 	free(buffer);
 }
diff --git a/date.c b/date.c
index 495c207c64f..5c33dfd8ee7 100644
--- a/date.c
+++ b/date.c
@@ -100,41 +100,41 @@ void show_date_relative(unsigned long time, int tz,
 	diff = now->tv_sec - time;
 	if (diff < 90) {
 		strbuf_addf(timebuf,
-			 Q_("%lu second ago", "%lu seconds ago", diff), diff);
+			 Q_("%"PRItime" second ago", "%"PRItime" seconds ago", diff), diff);
 		return;
 	}
 	/* Turn it into minutes */
 	diff = (diff + 30) / 60;
 	if (diff < 90) {
 		strbuf_addf(timebuf,
-			 Q_("%lu minute ago", "%lu minutes ago", diff), diff);
+			 Q_("%"PRItime" minute ago", "%"PRItime" minutes ago", diff), diff);
 		return;
 	}
 	/* Turn it into hours */
 	diff = (diff + 30) / 60;
 	if (diff < 36) {
 		strbuf_addf(timebuf,
-			 Q_("%lu hour ago", "%lu hours ago", diff), diff);
+			 Q_("%"PRItime" hour ago", "%"PRItime" hours ago", diff), diff);
 		return;
 	}
 	/* We deal with number of days from here on */
 	diff = (diff + 12) / 24;
 	if (diff < 14) {
 		strbuf_addf(timebuf,
-			 Q_("%lu day ago", "%lu days ago", diff), diff);
+			 Q_("%"PRItime" day ago", "%"PRItime" days ago", diff), diff);
 		return;
 	}
 	/* Say weeks for the past 10 weeks or so */
 	if (diff < 70) {
 		strbuf_addf(timebuf,
-			 Q_("%lu week ago", "%lu weeks ago", (diff + 3) / 7),
+			 Q_("%"PRItime" week ago", "%"PRItime" weeks ago", (diff + 3) / 7),
 			 (diff + 3) / 7);
 		return;
 	}
 	/* Say months for the past 12 months or so */
 	if (diff < 365) {
 		strbuf_addf(timebuf,
-			 Q_("%lu month ago", "%lu months ago", (diff + 15) / 30),
+			 Q_("%"PRItime" month ago", "%"PRItime" months ago", (diff + 15) / 30),
 			 (diff + 15) / 30);
 		return;
 	}
@@ -145,20 +145,20 @@ void show_date_relative(unsigned long time, int tz,
 		unsigned long months = totalmonths % 12;
 		if (months) {
 			struct strbuf sb = STRBUF_INIT;
-			strbuf_addf(&sb, Q_("%lu year", "%lu years", years), years);
+			strbuf_addf(&sb, Q_("%"PRItime" year", "%"PRItime" years", years), years);
 			strbuf_addf(timebuf,
 				 /* TRANSLATORS: "%s" is "<n> years" */
-				 Q_("%s, %lu month ago", "%s, %lu months ago", months),
+				 Q_("%s, %"PRItime" month ago", "%s, %"PRItime" months ago", months),
 				 sb.buf, months);
 			strbuf_release(&sb);
 		} else
 			strbuf_addf(timebuf,
-				 Q_("%lu year ago", "%lu years ago", years), years);
+				 Q_("%"PRItime" year ago", "%"PRItime" years ago", years), years);
 		return;
 	}
 	/* Otherwise, just years. Centuries is probably overkill. */
 	strbuf_addf(timebuf,
-		 Q_("%lu year ago", "%lu years ago", (diff + 183) / 365),
+		 Q_("%"PRItime" year ago", "%"PRItime" years ago", (diff + 183) / 365),
 		 (diff + 183) / 365);
 }
 
@@ -179,7 +179,7 @@ const char *show_date(unsigned long time, int tz, const struct date_mode *mode)
 
 	if (mode->type == DATE_UNIX) {
 		strbuf_reset(&timebuf);
-		strbuf_addf(&timebuf, "%lu", time);
+		strbuf_addf(&timebuf, "%"PRItime, time);
 		return timebuf.buf;
 	}
 
@@ -188,7 +188,7 @@ const char *show_date(unsigned long time, int tz, const struct date_mode *mode)
 
 	if (mode->type == DATE_RAW) {
 		strbuf_reset(&timebuf);
-		strbuf_addf(&timebuf, "%lu %+05d", time, tz);
+		strbuf_addf(&timebuf, "%"PRItime" %+05d", time, tz);
 		return timebuf.buf;
 	}
 
@@ -643,7 +643,7 @@ static void date_string(unsigned long date, int offset, struct strbuf *buf)
 		offset = -offset;
 		sign = '-';
 	}
-	strbuf_addf(buf, "%lu %c%02d%02d", date, sign, offset / 60, offset % 60);
+	strbuf_addf(buf, "%"PRItime" %c%02d%02d", date, sign, offset / 60, offset % 60);
 }
 
 /*
diff --git a/fetch-pack.c b/fetch-pack.c
index afb8b050248..6004cea60d4 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -395,7 +395,7 @@ static int find_common(struct fetch_pack_args *args,
 		packet_buf_write(&req_buf, "deepen %d", args->depth);
 	if (args->deepen_since) {
 		unsigned long max_age = approxidate(args->deepen_since);
-		packet_buf_write(&req_buf, "deepen-since %lu", max_age);
+		packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 	}
 	if (args->deepen_not) {
 		int i;
diff --git a/git-compat-util.h b/git-compat-util.h
index d78cc36dd1a..b2451a12d54 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -319,6 +319,7 @@ extern char *gitdirname(char *);
 #define PRIo32 "o"
 #endif
 
+#define PRItime "lu"
 #define parse_timestamp strtoul
 
 #ifndef PATH_SEP
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 801d26468e0..4e9e3628716 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -4135,7 +4135,7 @@ static int expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
 			printf("prune %s", message);
 	} else {
 		if (cb->newlog) {
-			fprintf(cb->newlog, "%s %s %s %lu %+05d\t%s",
+			fprintf(cb->newlog, "%s %s %s %"PRItime" %+05d\t%s",
 				oid_to_hex(ooid), oid_to_hex(noid),
 				email, timestamp, tz, message);
 			oidcpy(&cb->last_kept_oid, noid);
diff --git a/t/helper/test-date.c b/t/helper/test-date.c
index 52d1fc34454..269040f028f 100644
--- a/t/helper/test-date.c
+++ b/t/helper/test-date.c
@@ -53,7 +53,7 @@ static void parse_dates(const char **argv, struct timeval *now)
 
 		strbuf_reset(&result);
 		parse_date(*argv, &result);
-		if (sscanf(result.buf, "%lu %d", &t, &tz) == 2)
+		if (sscanf(result.buf, "%"PRItime" %d", &t, &tz) == 2)
 			printf("%s -> %s\n",
 			       *argv, show_date(t, tz, DATE_MODE(ISO8601)));
 		else
diff --git a/t/helper/test-parse-options.c b/t/helper/test-parse-options.c
index a01430c24bd..7d93627e454 100644
--- a/t/helper/test-parse-options.c
+++ b/t/helper/test-parse-options.c
@@ -161,7 +161,7 @@ int cmd_main(int argc, const char **argv)
 	show(&expect, &ret, "boolean: %d", boolean);
 	show(&expect, &ret, "integer: %d", integer);
 	show(&expect, &ret, "magnitude: %lu", magnitude);
-	show(&expect, &ret, "timestamp: %lu", timestamp);
+	show(&expect, &ret, "timestamp: %"PRItime, timestamp);
 	show(&expect, &ret, "string: %s", string ? string : "(not set)");
 	show(&expect, &ret, "abbrev: %d", abbrev);
 	show(&expect, &ret, "verbose: %d", verbose);
diff --git a/t/helper/test-ref-store.c b/t/helper/test-ref-store.c
index 2d84c45ffe9..a436bfdb053 100644
--- a/t/helper/test-ref-store.c
+++ b/t/helper/test-ref-store.c
@@ -141,7 +141,7 @@ static int each_reflog(struct object_id *old_oid, struct object_id *new_oid,
 		       const char *committer, unsigned long timestamp,
 		       int tz, const char *msg, void *cb_data)
 {
-	printf("%s %s %s %lu %d %s\n",
+	printf("%s %s %s %"PRItime" %d %s\n",
 	       oid_to_hex(old_oid), oid_to_hex(new_oid),
 	       committer, timestamp, tz, msg);
 	return 0;
diff --git a/upload-pack.c b/upload-pack.c
index f17f4dd1233..4966f0b8a09 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -863,7 +863,7 @@ static void receive_needs(void)
 
 		argv_array_push(&av, "rev-list");
 		if (deepen_since)
-			argv_array_pushf(&av, "--max-age=%lu", deepen_since);
+			argv_array_pushf(&av, "--max-age=%"PRItime, deepen_since);
 		if (deepen_not.nr) {
 			argv_array_push(&av, "--not");
 			for (i = 0; i < deepen_not.nr; i++) {
diff --git a/vcs-svn/fast_export.c b/vcs-svn/fast_export.c
index 97cba39cdf5..6c9f2866d8b 100644
--- a/vcs-svn/fast_export.c
+++ b/vcs-svn/fast_export.c
@@ -73,7 +73,7 @@ void fast_export_begin_note(uint32_t revision, const char *author,
 	static int firstnote = 1;
 	size_t loglen = strlen(log);
 	printf("commit %s\n", note_ref);
-	printf("committer %s <%s@%s> %lu +0000\n", author, author, "local", timestamp);
+	printf("committer %s <%s@%s> %"PRItime" +0000\n", author, author, "local", timestamp);
 	printf("data %"PRIuMAX"\n", (uintmax_t)loglen);
 	fwrite(log, loglen, 1, stdout);
 	if (firstnote) {
@@ -107,7 +107,7 @@ void fast_export_begin_commit(uint32_t revision, const char *author,
 	}
 	printf("commit %s\n", local_ref);
 	printf("mark :%"PRIu32"\n", revision);
-	printf("committer %s <%s@%s> %lu +0000\n",
+	printf("committer %s <%s@%s> %"PRItime" +0000\n",
 		   *author ? author : "nobody",
 		   *author ? author : "nobody",
 		   *uuid ? uuid : "local", timestamp);
-- 
2.12.2.windows.2.406.gd14a8f8640f