utils-std

commit: efb556f123a37119d65cf0d3d9dadd2c24d41905
parent 8206dfe4fda830164f3af6757edde50c54e4a833
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Mon, 29 Jul 2024 09:41:22 +0200

cmd/date: Add support for `-r epoch` option

In the future it might also support the `-r ref_file` variant
similarly to illumos.

Diffstat:
M
cmd/date.1.in
9
++++++++-
M
cmd/date.c
45
++++++++++++++++++++++++++++++++++++++++++---
M
test-cmd/date.sh
10
+++++++++-

3 files changed, 59 insertions(+), 5 deletions(-)
diff --git a/cmd/date.1.in b/cmd/date.1.in
@@ -10,7 +10,7 @@
 .Sh SYNOPSIS
 .Nm
 .Op Fl jRu
-.Op Fl d Ar datetime
+.Op Fl d Ar datetime | Fl r Ar epoch
 .Op Cm + Ns Ar format
 .Nm
 .Op Fl jRu
@@ -48,6 +48,11 @@ This allows to use the
 flag to convert one datetime to another.
 .It Fl u
 Use UTC (coordinated universal time) instead of the local time.
+.It Fl r Ar epoch
+Use
+.Ar epoch
+(seconds relative to 1970-01-01 00:00:00 UTC)
+instead of current datetime.
 .It Fl R
 Set the default value of
 .Ar format
@@ -110,6 +115,8 @@ options are present for compatibility with other modern systems such as
 NetBSD, BusyBox, and GNU coreutils.
 .br
 The
+.Fl r
+option is inspired from BSD and illumos,
 .Fl f
 and
 .Fl j
diff --git a/cmd/date.c b/cmd/date.c
@@ -23,7 +23,7 @@ usage()
 {
 	fprintf(stderr, "\
 Usage:\n\
-	date [-jRu] [-d datetime] [+format]\n\
+	date [-jRu] [-d datetime | -r epoch] [+format]\n\
 	date [-jRu] mmddHHMM[[CC]yy] [+format]\n\
 	date [-jRu] -f now_format now [+format]\n\
 ");
@@ -51,7 +51,7 @@ main(int argc, char *argv[])
 	char *format = "%c";
 	char *input_format = NULL;
 	int uflag = 0;
-	int dflag = 0;
+	int dflag = 0, rflag = 0;
 	int c;
 	bool jflag = false;
 	bool settime = false;
@@ -71,7 +71,7 @@ main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	while((c = getopt(argc, argv, ":d:f:jRu")) != -1)
+	while((c = getopt(argc, argv, ":d:f:jr:Ru")) != -1)
 	{
 		char *errstr = NULL;
 		switch(c)
@@ -82,6 +82,11 @@ main(int argc, char *argv[])
 				fprintf(stderr, "date: Cannot both use '-d' and '-f'\n");
 				exit(EXIT_FAILURE);
 			}
+			if(rflag == 1)
+			{
+				fprintf(stderr, "date: Cannot both use '-d' and '-r'\n");
+				exit(EXIT_FAILURE);
+			}
 
 			iso_parse(optarg, &tm, &tp.tv_nsec, &errstr);
 			dflag = 1;
@@ -107,9 +112,43 @@ main(int argc, char *argv[])
 				fprintf(stderr, "date: Cannot both use '-d' and '-f'\n");
 				exit(EXIT_FAILURE);
 			}
+			if(rflag == 1)
+			{
+				fprintf(stderr, "date: Cannot both use '-f' and '-r'\n");
+				exit(EXIT_FAILURE);
+			}
+
 			input_format = optarg;
 			settime = true;
 			break;
+		case 'r': /* seconds relative to epoch */
+		{
+			if(input_format != NULL)
+			{
+				fprintf(stderr, "date: Cannot both use '-f' and '-r'\n");
+				exit(EXIT_FAILURE);
+			}
+			if(dflag == 1)
+			{
+				fprintf(stderr, "date: Cannot both use '-d' and '-r'\n");
+				exit(EXIT_FAILURE);
+			}
+
+			char *endptr = NULL;
+			errno = 0;
+			tp.tv_sec = strtol(optarg, &endptr, 10);
+			if(errno != 0)
+			{
+				fprintf(stderr, "date: Failed parsing '-r %s'\n", optarg);
+				exit(EXIT_FAILURE);
+			}
+			if(!(endptr == NULL || *endptr == '\0'))
+			{
+				fprintf(stderr, "date: Error: Invalid characters in '-r %s': %s\n", optarg, endptr);
+				exit(EXIT_FAILURE);
+			}
+			break;
+		}
 		case 'R': /* Email (RFC 5322) format */
 			format = "%a, %d %b %Y %H:%M:%S %z";
 			break;
diff --git a/test-cmd/date.sh b/test-cmd/date.sh
@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: MPL-2.0
 
 target="$(dirname "$0")/../cmd/date"
-plans=19
+plans=22
 . "$(dirname "$0")/tap.sh"
 
 unset TZ
@@ -52,6 +52,14 @@ t 'mmddHHMM69' '-j 0628012069 +%Y-%m-%dT%H:%M' '1969-06-28T01:20
 t 'mmddHHMMCCyy' '-j 072505542024 +%Y-%m-%dT%H:%M' '2024-07-25T05:54
 '
 
+t 'r_0' '-u -r 0 +%FT%T' '1970-01-01T00:00:00
+'
+t 'r_69' '-u -r 69 +%FT%T' '1970-01-01T00:01:09
+'
+t 'r_-69' '-u -r -69 +%FT%T' '1969-12-31T23:58:51
+'
+
+
 #usage="\
 #date [-uR] [-d datetime] [+format]
 #date [-uR] -f now_format now [+format]