md5: Improve compatibility with coreutils and format fix

The previous changes that added support for the coreutils -c option
modified the output generated by passing -r to match that of the
coreutils versions. The difference is that coreutils separates the
hash from the file name by two blanks "  " (or a blank followed by
an asterisk " *" with the -b option denoting).

While most scripts or users will not notice the difference, it might
be considered a violation of POLA and this commit reverts the change
for the non-sum programs. These will print a single blank " " as the
separator, as they die before the previous commit.

In order to still generate output that is identical to that of the
coreutils programs, this commit generates the "  " or " *" separator
used by them for the -sum versions, depending on the presence of the
-b option.

(cherry picked from commit b33d1898c1b0e6d76b52eb48078260588802dc95)

2 files changed, 25 insertions, 10 deletions

diff --git a/sbin/md5/md5.1 b/sbin/md5/md5.1
index da034d1298c5..2b1da85c080f 100644
--- a/sbin/md5/md5.1
+++ b/sbin/md5/md5.1
@@ -1,5 +1,5 @@
 .\" $FreeBSD$
-.Dd June 24, 2021
+.Dd June 29, 2021
 .Dt MD5 1
 .Os
 .Sh NAME
@@ -77,9 +77,11 @@ The hexadecimal checksum of each file listed on the command line is printed
 after the options are processed.
 .Bl -tag -width indent
 .It Fl b
-Ignored for compatibility with the coreutils
+Make the
 .Nm -sum
-programs.
+programs separate hash and digest with a blank followed by an asterisk instead
+of by 2 blank characters for full compatibility with the output generated by the
+coreutils versions of these programs.
 .It Fl c Ar string
 If the program was called with a name that does not end in
 .Nm sum ,
@@ -88,13 +90,13 @@ compare the digest of the file against this string.
 .It Fl c Ar file
 If the program was called with a name that does end in
 .Nm sum ,
-the file passed as argument must contain digest lines generated by the same digest algorithm
-with or without the
+the file passed as argument must contain digest lines generated by the same
+digest algorithm with or without the
 .Fl r
 option
 .Pq i.e. in either classical BSD format or in GNU coreutils format .
-A line with file name followed by
-.Dq :
+A line with the file name followed by a colon
+.Dq ":"
 and either OK or FAILED is written for each well-formed line in the digest file.
 If applicable, the number of failed comparisons and the number of lines that were
 skipped since they were not well-formed are printed at the end.
@@ -157,8 +159,13 @@ $ echo -n Hello | md5
 Calculate the checksum of multiple files reversing the output:
 .Bd -literal -offset indent
 $ md5 -r /boot/loader.conf /etc/rc.conf
-ada5f60f23af88ff95b8091d6d67bef6  /boot/loader.conf
-d80bf36c332dc0fdc479366ec3fa44cd  /etc/rc.conf
+ada5f60f23af88ff95b8091d6d67bef6 /boot/loader.conf
+d80bf36c332dc0fdc479366ec3fa44cd /etc/rc.conf
+.Pd
+The
+.Nm -sum
+variants put 2 blank characters between hash and file name for full compatibilty
+with the coreutils versions of these commands.
 .Ed
 .Pp
 Write the digest for
diff --git a/sbin/md5/md5.c b/sbin/md5/md5.c
index 43a76227a9d2..7235e6e0a39f 100644
--- a/sbin/md5/md5.c
+++ b/sbin/md5/md5.c
@@ -54,6 +54,7 @@ __FBSDID("$FreeBSD$");
 #define TEST_BLOCK_COUNT 100000
 #define MDTESTCOUNT 8
 
+static int bflag;
 static int cflag;
 static int pflag;
 static int qflag;
@@ -301,6 +302,7 @@ main(int argc, char *argv[])
 	while ((ch = getopt(argc, argv, "bc:pqrs:tx")) != -1)
 		switch (ch) {
 		case 'b':
+			bflag = 1;
 			break;
 		case 'c':
 			cflag = 1;
@@ -436,7 +438,13 @@ MDOutput(const Algorithm_t *alg, char *p, char *argv[])
 			printf("%s\n", p);
 		} else {
 			if (rflag)
-				printf("%s  %s", p, *argv);
+				if (gnu_emu)
+					if (bflag)
+						printf("%s *%s", p, *argv);
+					else
+						printf("%s  %s", p, *argv);
+				else
+					printf("%s %s", p, *argv);
 			else
 				printf("%s (%s) = %s", alg->name, *argv, p);
 			if (checkAgainst) {