utils

commit: c81e81c9fba64342444084a8628c55df84605734
parent 4087f6a16718ffe7ca31ec4909ad7701e925b84b
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Fri,  7 Jul 2023 20:13:41 +0200

cmd/env: Add support for --unset

Quite a hack to avoid depending on GNU's getopt_long(3).

Diffstat:
M
cmd/env.1
7
++++---
M
cmd/env.c
23
+++++++++++++++++++++--
M
test-cmd/env
14
++++++++++++--

3 files changed, 37 insertions(+), 7 deletions(-)
diff --git a/cmd/env.1 b/cmd/env.1
@@ -11,7 +11,8 @@
 .Nm
 .Op Fl i
 .Op Fl u Ar name
-.Op Ar name=value
+.Op Fl -unset= Ns Ar name
+.Op Ar name Ns = Ns Ar value
 .Op Ar command Op Ar argument ...
 .Sh DESCRIPTION
 .Nm
@@ -22,11 +23,11 @@ The environment can be modified via the following options:
 .Bl -tag -width Ds
 .It Fl i
 Ignore the existing environment.
-.It Fl u Ar name
+.It Fl u Ar name | Fl -unset= Ns Ar name
 Removes the variable named
 .Ar name
 from the new environment.
-.It Ar name=value
+.It Ar name Ns = Ns Ar value
 Adds the variable named
 .Ar name
 with the value
diff --git a/cmd/env.c b/cmd/env.c
@@ -33,7 +33,7 @@ int export()
 void
 usage()
 {
-	fprintf(stderr, "env [-i] [-u key] [key=value ...] [command [args]]\n");
+	fprintf(stderr, "env [-i] [-u key | --unset=key] [key=value ...] [command [args]]\n");
 }
 
 int
@@ -43,7 +43,7 @@ main(int argc, char *argv[])
 	bool flag_i = false;
 
 	/* flawfinder: ignore. Old implementations of getopt should fix themselves */
-	while((c = getopt(argc, argv, ":iu:")) != -1)
+	while((c = getopt(argc, argv, ":iu:-:")) != -1)
 	{
 		switch(c)
 		{
@@ -53,6 +53,25 @@ main(int argc, char *argv[])
 		case 'u':
 			unsetenv(optarg);
 			break;
+		case '-':
+			char *val = strchr(optarg, '=');
+			if(val == NULL)
+			{
+				fprintf(stderr, "env: Error: Missing = in long option\n", optopt);
+				return 1;
+			}
+
+			*val = 0;
+			val++;
+
+			if(strcmp(optarg, "unset") != 0)
+			{
+				fprintf(stderr, "env: Error: Unknown long option --%s\n", optarg);
+				return 1;
+			}
+			unsetenv(val);
+
+			break;
 		case ':':
 			fprintf(stderr, "env: Error: Missing operand for option: '-%c'\n", optopt);
 			usage();
diff --git a/test-cmd/env b/test-cmd/env
@@ -11,7 +11,7 @@ noargs_body() {
 
 atf_test_case badarg
 badarg_body() {
-	atf_check -s not-exit:0 -e "inline:env: Error: Unrecognised option: '-f'\nenv [-i] [-u key] [key=value ...] [command [args]]\n" ../cmd/env -f
+	atf_check -s not-exit:0 -e "inline:env: Error: Unrecognised option: '-f'\nenv [-i] [-u key | --unset=key] [key=value ...] [command [args]]\n" ../cmd/env -f
 }
 
 atf_test_case iflag
@@ -30,7 +30,16 @@ uflag_body() {
 
 	atf_check -o "inline:FOO=BAR\n" ../cmd/env -i FOO=BAR BAR=FOO ../cmd/env -u BAR
 
-	atf_check -s not-exit:0 -e "inline:env: Error: Missing operand for option: '-u'\nenv [-i] [-u key] [key=value ...] [command [args]]\n" ../cmd/env -u
+	atf_check -s not-exit:0 -e "inline:env: Error: Missing operand for option: '-u'\nenv [-i] [-u key | --unset=key] [key=value ...] [command [args]]\n" ../cmd/env -u
+}
+
+atf_test_case unsetflag
+unsetflag_body() {
+	[ "${LD_PRELOAD}" = "libsandbox.so" ] && atf_expect_fail "sandbox (gentoo) interferes with the environment"
+
+	atf_check -o "inline:FOO=BAR\n" ../cmd/env -i FOO=BAR BAR=FOO ../cmd/env --unset=BAR
+
+	atf_check -s not-exit:0 -e "inline:env: Error: Missing operand for option: '-u'\nenv [-i] [-u key | --unset=key] [key=value ...] [command [args]]\n" ../cmd/env -u
 }
 
 atf_test_case devfull
@@ -57,6 +66,7 @@ atf_init_test_cases() {
 	atf_add_test_case badarg
 	atf_add_test_case iflag
 	atf_add_test_case uflag
+	atf_add_test_case unsetflag
 	atf_add_test_case devfull
 	atf_add_test_case noutil
 	atf_add_test_case false