From 63c8336d4de15085d50c9d8c855cdc97ee018a04 Mon Sep 17 00:00:00 2001
From: Eric van Gyzen <vangyzen@FreeBSD.org>
Date: Thu, 1 Oct 2020 21:48:22 +0000
Subject: [PATCH] zgrep: fix exit status with multiple files

zgrep should exit with success when given multiple files and the
pattern is found in at least one file.  Prior to this change,
it would exit with success only if the pattern was found in _every_ file.

Reviewed by:	dab ngie
MFC after:	2 weeks
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D26616
---
 contrib/netbsd-tests/usr.bin/grep/t_grep.sh | 19 +++++++++++++++++++
 usr.bin/grep/zgrep.sh                       | 17 ++++++++++++-----
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/contrib/netbsd-tests/usr.bin/grep/t_grep.sh b/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
index 75ee254cc79b..e094b15c6d67 100755
--- a/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
+++ b/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
@@ -891,6 +891,24 @@ mflag_body()
 
 	atf_check -o inline:"test1:2\n" grep -m 2 -EHc "a|b|e|f" test1
 }
+
+atf_test_case zgrep_multiple_files
+zgrep_multiple_files_head()
+{
+	atf_set "descr" "Ensures that zgrep functions properly with multiple files"
+}
+zgrep_multiple_files_body()
+{
+	echo foo > test1
+	echo foo > test2
+	atf_check -o inline:"test1:foo\ntest2:foo\n" zgrep foo test1 test2
+
+	echo bar > test1
+	atf_check -o inline:"test2:foo\n" zgrep foo test1 test2
+
+	echo bar > test2
+	atf_check -s exit:1 zgrep foo test1 test2
+}
 # End FreeBSD
 
 atf_init_test_cases()
@@ -944,5 +962,6 @@ atf_init_test_cases()
 	atf_add_test_case fgrep_oflag
 	atf_add_test_case cflag
 	atf_add_test_case mflag
+	atf_add_test_case zgrep_multiple_files
 # End FreeBSD
 }
diff --git a/usr.bin/grep/zgrep.sh b/usr.bin/grep/zgrep.sh
index acbcb48770a7..7e44c7053492 100755
--- a/usr.bin/grep/zgrep.sh
+++ b/usr.bin/grep/zgrep.sh
@@ -157,28 +157,35 @@ then
     pattern_found=1
 fi
 
-ret=0
 # call grep ...
 if [ $# -lt 1 ]
 then
     # ... on stdin
     if [ ${pattern_file} -eq 0 ]; then
-	${cattool} ${catargs} - | ${grep} ${grep_args} -- "${pattern}" - || ret=$?
+	${cattool} ${catargs} - | ${grep} ${grep_args} -- "${pattern}" -
     else
-	${cattool} ${catargs} - | ${grep} ${grep_args} -- - || ret=$?
+	${cattool} ${catargs} - | ${grep} ${grep_args} -- -
     fi
+    ret=$?
 else
     # ... on all files given on the command line
     if [ ${silent} -lt 1 -a $# -gt 1 ]; then
 	grep_args="-H ${grep_args}"
     fi
+    # Succeed if any file matches.  First assume no match.
+    ret=1
     for file; do
 	if [ ${pattern_file} -eq 0 ]; then
 	    ${cattool} ${catargs} -- "${file}" |
-		${grep} --label="${file}" ${grep_args} -- "${pattern}" - || ret=$?
+		${grep} --label="${file}" ${grep_args} -- "${pattern}" -
 	else
 	    ${cattool} ${catargs} -- "${file}" |
-		${grep} --label="${file}" ${grep_args} -- - || ret=$?
+		${grep} --label="${file}" ${grep_args} -- -
+	fi
+	this_ret=$?
+	# A match (0) overrides a no-match (1).  An error (>=2) overrides all.
+	if [ ${this_ret} -eq 0 -a ${ret} -eq 1 ] || [ ${this_ret} -ge 2 ]; then
+	    ret=${this_ret}
 	fi
     done
 fi