Rework the kernel environment subsystem. We now convert the static

environment needed at boot time to a dynamic subsystem when VM is
up.  The dynamic kernel environment is protected by an sx lock.

This adds some new functions to manipulate the kernel environment :
freeenv(), setenv(), unsetenv() and testenv().  freeenv() has to be
called after every getenv() when you have finished using the string.
testenv() only tests if an environment variable is present, and
doesn't require a freeenv() call. setenv() and unsetenv() are self
explanatory.

The kenv(2) syscall exports these new functionalities to userland,
mainly for kenv(1).

Reviewed by:	peter

1 files changed, 7 insertions, 0 deletions

diff --git a/sys/sys/sysproto.h b/sys/sys/sysproto.h
index 1f4b987..80385c0 100644
--- a/sys/sys/sysproto.h
+++ b/sys/sys/sysproto.h
@@ -1105,6 +1105,12 @@ struct thread_wakeup_args {
 struct kse_yield_args {
 	register_t dummy;
 };
+struct kenv_args {
+	char what_l_[PADL_(int)]; int what; char what_r_[PADR_(int)];
+	char name_l_[PADL_(const char *)]; const char * name; char name_r_[PADR_(const char *)];
+	char value_l_[PADL_(char *)]; char * value; char value_r_[PADR_(char *)];
+	char len_l_[PADL_(int)]; int len; char len_r_[PADR_(int)];
+};
 int	nosys(struct thread *, struct nosys_args *);
 void	sys_exit(struct thread *, struct sys_exit_args *);
 int	fork(struct thread *, struct fork_args *);
@@ -1354,6 +1360,7 @@ int	kse_wakeup(struct thread *, struct kse_wakeup_args *);
 int	kse_new(struct thread *, struct kse_new_args *);
 int	thread_wakeup(struct thread *, struct thread_wakeup_args *);
 int	kse_yield(struct thread *, struct kse_yield_args *);
+int	kenv(struct thread *, struct kenv_args *);
 
 #ifdef COMPAT_43