3 files changed, 98 insertions, 30 deletions

diff --git a/contrib/netbsd-tests/usr.bin/grep/t_grep.sh b/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
index d6d0d46f4ac3..c5c47e992378 100755
--- a/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
+++ b/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
@@ -413,6 +413,60 @@ wflag_emptypat_body()
 	atf_check -o file:test4 grep -w -e "" test4
 }
 
+atf_test_case xflag_emptypat
+xflag_emptypat_body()
+{
+	printf "" > test1
+	printf "\n" > test2
+	printf "qaz" > test3
+	printf " qaz\n" > test4
+
+	# -x is whole-line, more strict than -w.
+	atf_check -s exit:1 -o empty grep -x -e "" test1
+
+	atf_check -o file:test2 grep -x -e "" test2
+
+	atf_check -s exit:1 -o empty grep -x -e "" test3
+
+	atf_check -s exit:1 -o empty grep -x -e "" test4
+
+	total=$(wc -l /COPYRIGHT | sed 's/[^0-9]//g')
+
+	# Simple checks that grep -x with an empty pattern isn't matching every
+	# line.  The exact counts aren't important, as long as they don't
+	# match the total line count and as long as they don't match each other.
+	atf_check -o save:xpositive.count grep -Fxc '' /COPYRIGHT
+	atf_check -o save:xnegative.count grep -Fvxc '' /COPYRIGHT
+
+	atf_check -o not-inline:"${total}" cat xpositive.count
+	atf_check -o not-inline:"${total}" cat xnegative.count
+
+	atf_check -o not-file:xnegative.count cat xpositive.count
+}
+
+atf_test_case xflag_emptypat_plus
+xflag_emptypat_plus_body()
+{
+	printf "foo\n\nbar\n\nbaz\n" > target
+	printf "foo\n \nbar\n \nbaz\n" > target_spacelines
+	printf "foo\nbar\nbaz\n" > matches
+	printf " \n \n" > spacelines
+
+	printf "foo\n\nbar\n\nbaz\n" > patlist1
+	printf "foo\n\nba\n\nbaz\n" > patlist2
+
+	sed -e '/bar/d' target > matches_not2
+
+	# Normal handling first
+	atf_check -o file:target grep -Fxf patlist1 target
+	atf_check -o file:matches grep -Fxf patlist1 target_spacelines
+	atf_check -o file:matches_not2 grep -Fxf patlist2 target
+
+	# -v handling
+	atf_check -s exit:1 -o empty grep -Fvxf patlist1 target
+	atf_check -o file:spacelines grep -Fxvf patlist1 target_spacelines
+}
+
 atf_test_case excessive_matches
 excessive_matches_head()
 {
@@ -551,6 +605,12 @@ grep_nomatch_flags_head()
 
 grep_nomatch_flags_body()
 {
+	grep_type
+
+	if [ $? -eq $GREP_TYPE_GNU_FREEBSD ]; then
+		atf_expect_fail "this test does not pass with GNU grep in base"
+	fi
+
 	printf "A\nB\nC\n" > test1
 
 	atf_check -o inline:"1\n" grep -c -C 1 -e "B" test1
@@ -563,7 +623,7 @@ grep_nomatch_flags_body()
 	atf_check -o inline:"test1\n" grep -l -A 1 -e "B" test1
 	atf_check -o inline:"test1\n" grep -l -C 1 -e "B" test1
 
-	atf_check -s exit:1 -o inline:"test1\n" grep -L -e "D" test1
+	atf_check -o inline:"test1\n" grep -L -e "D" test1
 
 	atf_check -o empty grep -q -e "B" test1
 	atf_check -o empty grep -q -B 1 -e "B" test1
@@ -777,6 +837,8 @@ atf_init_test_cases()
 	atf_add_test_case egrep_empty_invalid
 	atf_add_test_case zerolen
 	atf_add_test_case wflag_emptypat
+	atf_add_test_case xflag_emptypat
+	atf_add_test_case xflag_emptypat_plus
 	atf_add_test_case excessive_matches
 	atf_add_test_case wv_combo_break
 	atf_add_test_case fgrep_sanity
diff --git a/usr.bin/grep/grep.c b/usr.bin/grep/grep.c
index 20911c294343..731e46bb112e 100644
--- a/usr.bin/grep/grep.c
+++ b/usr.bin/grep/grep.c
@@ -218,20 +218,9 @@ static void
 add_pattern(char *pat, size_t len)
 {
 
-	/* Do not add further pattern is we already match everything */
-	if (matchall)
-	  return;
-
 	/* Check if we can do a shortcut */
 	if (len == 0) {
 		matchall = true;
-		for (unsigned int i = 0; i < patterns; i++) {
-			free(pattern[i].pat);
-		}
-		pattern = grep_realloc(pattern, sizeof(struct pat));
-		pattern[0].pat = NULL;
-		pattern[0].len = 0;
-		patterns = 1;
 		return;
 	}
 	/* Increase size if necessary */
@@ -654,7 +643,7 @@ main(int argc, char *argv[])
 	aargv += optind;
 
 	/* Empty pattern file matches nothing */
-	if (!needpattern && (patterns == 0))
+	if (!needpattern && (patterns == 0) && !matchall)
 		exit(1);
 
 	/* Fail if we don't have any pattern */
@@ -701,11 +690,10 @@ main(int argc, char *argv[])
 
 	r_pattern = grep_calloc(patterns, sizeof(*r_pattern));
 
-	/* Don't process any patterns if we have a blank one */
 #ifdef WITH_INTERNAL_NOSPEC
-	if (!matchall && grepbehave != GREP_FIXED) {
+	if (grepbehave != GREP_FIXED) {
 #else
-	if (!matchall) {
+	{
 #endif
 		/* Check if cheating is allowed (always is for fgrep). */
 		for (i = 0; i < patterns; ++i) {
@@ -737,7 +725,12 @@ main(int argc, char *argv[])
 				matched = true;
 		}
 
-	/* Find out the correct return value according to the
-	   results and the command line option. */
+	if (Lflag)
+		matched = !matched;
+
+	/*
+	 * Calculate the correct return value according to the
+	 * results and the command line option.
+	 */
 	exit(matched ? (file_err ? (qflag ? 0 : 2) : 0) : (file_err ? 2 : 1));
 }
diff --git a/usr.bin/grep/util.c b/usr.bin/grep/util.c
index 07d9b40cbdcd..33afe4d6b030 100644
--- a/usr.bin/grep/util.c
+++ b/usr.bin/grep/util.c
@@ -210,7 +210,7 @@ procmatch_match(struct mprintc *mc, struct parsec *pc)
 		while (pc->matchidx >= MAX_MATCHES) {
 			/* Reset matchidx and try again */
 			pc->matchidx = 0;
-			if (procline(pc))
+			if (procline(pc) == !vflag)
 				printline(pc, ':');
 			else
 				break;
@@ -355,7 +355,7 @@ procfile(const char *fn)
 			return (0);
 		}
 
-		line_matched = procline(&pc);
+		line_matched = procline(&pc) == !vflag;
 		if (line_matched)
 			++lines;
 
@@ -469,17 +469,32 @@ procline(struct parsec *pc)
 
 	matchidx = pc->matchidx;
 
-	/* Special case: empty pattern with -w flag, check first character */
-	if (matchall && wflag) {
+	/*
+	 * With matchall (empty pattern), we can try to take some shortcuts.
+	 * Emtpy patterns trivially match every line except in the -w and -x
+	 * cases.  For -w (whole-word) cases, we only match if the first
+	 * character isn't a word-character.  For -x (whole-line) cases, we only
+	 * match if the line is empty.
+	 */
+	if (matchall) {
 		if (pc->ln.len == 0)
 			return (true);
-		wend = L' ';
-		if (sscanf(&pc->ln.dat[0], "%lc", &wend) != 1 || iswword(wend))
-			return (false);
-		else
+		if (wflag) {
+			wend = L' ';
+			if (sscanf(&pc->ln.dat[0], "%lc", &wend) == 1 &&
+			    !iswword(wend))
+				return (true);
+		} else if (!xflag)
 			return (true);
-	} else if (matchall)
-		return (true);
+
+		/*
+		 * If we don't have any other patterns, we really don't match.
+		 * If we do have other patterns, we must fall through and check
+		 * them.
+		 */
+		if (patterns == 0)
+			return (false);
+	}
 
 	matched = false;
 	st = pc->lnstart;
@@ -609,8 +624,6 @@ procline(struct parsec *pc)
 
 	/* Reflect the new matchidx in the context */
 	pc->matchidx = matchidx;
-	if (vflag)
-		matched = !matched;
 	return matched;
 }