3 files changed, 18 insertions, 9 deletions

diff --git a/drivers/unix/dir_access_unix.cpp b/drivers/unix/dir_access_unix.cpp
index 557060c907..a162f46103 100644
--- a/drivers/unix/dir_access_unix.cpp
+++ b/drivers/unix/dir_access_unix.cpp
@@ -189,7 +189,7 @@ void DirAccessUnix::list_dir_end() {
 	_cisdir = false;
 }
 
-#if defined(HAVE_MNTENT) && defined(X11_ENABLED)
+#if defined(HAVE_MNTENT) && defined(LINUXBSD_ENABLED)
 static bool _filter_drive(struct mntent *mnt) {
 	// Ignore devices that don't point to /dev
 	if (strncmp(mnt->mnt_fsname, "/dev", 4) != 0) {
@@ -213,7 +213,7 @@ static void _get_drives(List<String> *list) {
 	// Add root.
 	list->push_back("/");
 
-#if defined(HAVE_MNTENT) && defined(X11_ENABLED)
+#if defined(HAVE_MNTENT) && defined(LINUXBSD_ENABLED)
 	// Check /etc/mtab for the list of mounted partitions.
 	FILE *mtab = setmntent("/etc/mtab", "r");
 	if (mtab) {
diff --git a/drivers/unix/os_unix.cpp b/drivers/unix/os_unix.cpp
index c37b3d9c87..178f01b185 100644
--- a/drivers/unix/os_unix.cpp
+++ b/drivers/unix/os_unix.cpp
@@ -411,10 +411,6 @@ bool OS_Unix::is_process_running(const ProcessID &p_pid) const {
 	return true;
 }
 
-bool OS_Unix::has_environment(const String &p_var) const {
-	return getenv(p_var.utf8().get_data()) != nullptr;
-}
-
 String OS_Unix::get_locale() const {
 	if (!has_environment("LANG")) {
 		return "en";
@@ -487,6 +483,10 @@ Error OS_Unix::set_cwd(const String &p_cwd) {
 	return OK;
 }
 
+bool OS_Unix::has_environment(const String &p_var) const {
+	return getenv(p_var.utf8().get_data()) != nullptr;
+}
+
 String OS_Unix::get_environment(const String &p_var) const {
 	if (getenv(p_var.utf8().get_data())) {
 		return getenv(p_var.utf8().get_data());
@@ -494,8 +494,15 @@ String OS_Unix::get_environment(const String &p_var) const {
 	return "";
 }
 
-bool OS_Unix::set_environment(const String &p_var, const String &p_value) const {
-	return setenv(p_var.utf8().get_data(), p_value.utf8().get_data(), /* overwrite: */ true) == 0;
+void OS_Unix::set_environment(const String &p_var, const String &p_value) const {
+	ERR_FAIL_COND_MSG(p_var.is_empty() || p_var.contains("="), vformat("Invalid environment variable name '%s', cannot be empty or include '='.", p_var));
+	int err = setenv(p_var.utf8().get_data(), p_value.utf8().get_data(), /* overwrite: */ 1);
+	ERR_FAIL_COND_MSG(err != 0, vformat("Failed setting environment variable '%s', the system is out of memory.", p_var));
+}
+
+void OS_Unix::unset_environment(const String &p_var) const {
+	ERR_FAIL_COND_MSG(p_var.is_empty() || p_var.contains("="), vformat("Invalid environment variable name '%s', cannot be empty or include '='.", p_var));
+	unsetenv(p_var.utf8().get_data());
 }
 
 String OS_Unix::get_user_data_dir() const {
diff --git a/drivers/unix/os_unix.h b/drivers/unix/os_unix.h
index 416311307c..03429622ae 100644
--- a/drivers/unix/os_unix.h
+++ b/drivers/unix/os_unix.h
@@ -81,7 +81,9 @@ public:
 
 	virtual bool has_environment(const String &p_var) const override;
 	virtual String get_environment(const String &p_var) const override;
-	virtual bool set_environment(const String &p_var, const String &p_value) const override;
+	virtual void set_environment(const String &p_var, const String &p_value) const override;
+	virtual void unset_environment(const String &p_var) const override;
+
 	virtual String get_locale() const override;
 
 	virtual void initialize_debugging() override;