From 9c745c44d32284c4daf9d517429b96b4823f3d0b Mon Sep 17 00:00:00 2001
From: Doug Coleman <doug.coleman@gmail.com>
Date: Fri, 21 Mar 2008 14:53:11 -0500
Subject: [PATCH] add set-priority and get-priority add clear_err_no and
 check-errno for dealing with get-priority

---
 extra/io/priority/priority.factor      |  5 +++++
 extra/io/unix/backend/backend.factor   |  3 +++
 extra/io/unix/priority/priority.factor | 21 +++++++++++++++++++++
 extra/io/unix/unix.factor              |  2 +-
 extra/unix/unix.factor                 |  1 +
 vm/io.c                                |  5 +++++
 vm/io.h                                |  1 +
 7 files changed, 37 insertions(+), 1 deletion(-)
 create mode 100644 extra/io/priority/priority.factor
 create mode 100644 extra/io/unix/priority/priority.factor

diff --git a/extra/io/priority/priority.factor b/extra/io/priority/priority.factor
new file mode 100644
index 0000000000..0790563072
--- /dev/null
+++ b/extra/io/priority/priority.factor
@@ -0,0 +1,5 @@
+USING: io.backend kernel ;
+IN: io.priority
+
+HOOK: get-priority io-backend ( -- n )
+HOOK: set-priority io-backend ( n -- )
diff --git a/extra/io/unix/backend/backend.factor b/extra/io/unix/backend/backend.factor
index 93691c63e2..c9bd331bcd 100755
--- a/extra/io/unix/backend/backend.factor
+++ b/extra/io/unix/backend/backend.factor
@@ -72,6 +72,9 @@ M: mx unregister-io-task ( task mx -- )
 
 : (io-error) ( -- * ) err_no strerror throw ;
 
+: check-errno ( -- )
+    err_no dup zero? [ drop ] [ strerror throw ] if ;
+
 : check-null ( n -- ) zero? [ (io-error) ] when ;
 
 : io-error ( n -- ) 0 < [ (io-error) ] when ;
diff --git a/extra/io/unix/priority/priority.factor b/extra/io/unix/priority/priority.factor
new file mode 100644
index 0000000000..deb801e3cf
--- /dev/null
+++ b/extra/io/unix/priority/priority.factor
@@ -0,0 +1,21 @@
+USING: alien.syntax kernel io.priority io.unix.backend
+unix ;
+IN: io.unix.priority
+
+: PRIO_PROCESS 0 ; inline
+: PRIO_PGRP 1 ; inline
+: PRIO_USER 2 ; inline
+
+: PRIO_MIN -20 ; inline
+: PRIO_MAX 20 ; inline
+
+! which/who = 0 for current process
+FUNCTION: int getpriority ( int which, int who ) ;
+FUNCTION: int setpriority ( int which, int who, int prio ) ;
+
+M: unix-io get-priority ( -- n )
+    clear_err_no
+    0 0 getpriority dup -1 = [ check-errno ] when ;
+
+M: unix-io set-priority ( n -- )
+    0 0 rot setpriority io-error ;
diff --git a/extra/io/unix/unix.factor b/extra/io/unix/unix.factor
index 1f0492a060..83a455c29a 100755
--- a/extra/io/unix/unix.factor
+++ b/extra/io/unix/unix.factor
@@ -1,5 +1,5 @@
 USING: io.unix.backend io.unix.files io.unix.sockets io.timeouts
-io.unix.launcher io.unix.mmap io.backend
+io.unix.launcher io.unix.mmap io.backend io.priority
 combinators namespaces system vocabs.loader sequences ;
 
 "io.unix." os append require
diff --git a/extra/unix/unix.factor b/extra/unix/unix.factor
index e1d49b8c6c..09d77fee11 100755
--- a/extra/unix/unix.factor
+++ b/extra/unix/unix.factor
@@ -27,6 +27,7 @@ TYPEDEF: ulong size_t
 ! ! ! Unix functions
 LIBRARY: factor
 FUNCTION: int err_no ( ) ;
+FUNCTION: void clear_err_no ( ) ;
 
 LIBRARY: libc
 
diff --git a/vm/io.c b/vm/io.c
index faf681bbef..bc561f5e5b 100755
--- a/vm/io.c
+++ b/vm/io.c
@@ -194,3 +194,8 @@ int err_no(void)
 {
 	return errno;
 }
+
+void clear_err_no(void)
+{
+	errno = 0;
+}
diff --git a/vm/io.h b/vm/io.h
index 6291db50ee..f4af9b8bec 100755
--- a/vm/io.h
+++ b/vm/io.h
@@ -1,6 +1,7 @@
 void init_c_io(void);
 void io_error(void);
 int err_no(void);
+void clear_err_no(void);
 
 DECLARE_PRIMITIVE(fopen);
 DECLARE_PRIMITIVE(fgetc);