[src/trunk]: src/sys Framework for sysctl descriptions. Implementation to fo...

[atatat <atatat%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/161a9b18c4b8
branches:  trunk
changeset: 559841:161a9b18c4b8
user:      atatat <atatat%NetBSD.org@localhost>
date:      Wed Mar 24 17:40:02 2004 +0000

description:
Framework for sysctl descriptions.  Implementation to follow shortly.

diffstat:

 sys/kern/kern_sysctl.c |  35 ++++++++++++++++++++++++++++++-----
 sys/sys/sysctl.h       |  35 ++++++++++++++++++++++++++++++++++-
 2 files changed, 64 insertions(+), 6 deletions(-)

diffs (147 lines):

diff -r fc01f998a87a -r 161a9b18c4b8 sys/kern/kern_sysctl.c
--- a/sys/kern/kern_sysctl.c    Wed Mar 24 17:26:53 2004 +0000
+++ b/sys/kern/kern_sysctl.c    Wed Mar 24 17:40:02 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_sysctl.c,v 1.164 2004/03/24 17:21:02 atatat Exp $ */
+/*     $NetBSD: kern_sysctl.c,v 1.165 2004/03/24 17:40:02 atatat Exp $ */
 
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -75,7 +75,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sysctl.c,v 1.164 2004/03/24 17:21:02 atatat Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sysctl.c,v 1.165 2004/03/24 17:40:02 atatat Exp $");
 
 #include "opt_defcorename.h"
 #include "opt_insecure.h"
@@ -410,6 +410,9 @@
                case CTL_MMAP:
                        fn = (sysctlfn)sysctl_mmap; /* we own the rnode */
                        break;
+               case CTL_DESCRIBE:
+                       fn = sysctl_describe;
+                       break;
                default:
                        error = EOPNOTSUPP;
                        break;
@@ -573,9 +576,8 @@
 }
 
 /*
- * sysctl_query -- The auto-discovery engine.  Copies out the
- * descriptions on nodes under the given node and handles overlay
- * trees.
+ * sysctl_query -- The auto-discovery engine.  Copies out the structs
+ * describing nodes under the given node and handles overlay trees.
  */
 int
 sysctl_query(SYSCTLFN_ARGS)
@@ -1578,6 +1580,29 @@
        return ((*node->sysctl_func)(SYSCTLFN_CALL(node)));
 }
 
+int
+sysctl_describe(SYSCTLFN_ARGS)
+{
+
+       if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) {
+               printf("sysctl_query: rnode %p wrong version\n", rnode);
+               return (EINVAL);
+       }
+
+       if (SYSCTL_TYPE(rnode->sysctl_flags) != CTLTYPE_NODE)
+               return (ENOTDIR);
+       if (namelen != 1 || name[0] != CTL_DESCRIBE)
+               return (EINVAL);
+
+       /*
+        * implementation to be filled in later
+        */
+
+       *oldlenp = 0;
+
+       return (0);
+}
+
 /*
  * ********************************************************************
  * Section 3: Create and destroy from inside the kernel
diff -r fc01f998a87a -r 161a9b18c4b8 sys/sys/sysctl.h
--- a/sys/sys/sysctl.h  Wed Mar 24 17:26:53 2004 +0000
+++ b/sys/sys/sysctl.h  Wed Mar 24 17:40:02 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sysctl.h,v 1.112 2004/03/24 17:21:02 atatat Exp $      */
+/*     $NetBSD: sysctl.h,v 1.113 2004/03/24 17:40:02 atatat Exp $      */
 
 /*
  * Copyright (c) 1989, 1993
@@ -46,6 +46,13 @@
 #include <sys/proc.h>
 #include <uvm/uvm_extern.h>
 
+/* For offsetof() */
+#ifdef _KERNEL
+#include <sys/systm.h>
+#else
+#include <stddef.h>
+#endif
+
 /*
  * Definitions for sysctl call.  The sysctl call uses a hierarchical name
  * for objects that can be examined or modified.  The name is expressed as
@@ -97,6 +104,7 @@
 #define CTLFLAG_HIDDEN         0x00008000
 #define CTLFLAG_ALIAS          0x00010000
 #define CTLFLAG_MMAP           0x00020000
+#define CTLFLAG_OWNDESC                0x00040000
 
 /*
  * sysctl API version
@@ -135,6 +143,7 @@
 #define CTL_CREATESYM  -4              /* node create request with symbol */
 #define CTL_DESTROY    -5              /* node destroy request */
 #define CTL_MMAP       -6              /* mmap request */
+#define CTL_DESCRIBE   -7              /* get node descriptions */
 
 /*
  * Top-level identifiers
@@ -944,6 +953,7 @@
 int    sysctl_create(SYSCTLFN_RWPROTO);
 int    sysctl_destroy(SYSCTLFN_RWPROTO);
 int    sysctl_lookup(SYSCTLFN_RWPROTO);
+int    sysctl_describe(SYSCTLFN_PROTO);
 
 /*
  * simple variadic interface for adding/removing nodes
@@ -1095,6 +1105,29 @@
 #define sysctl_idata   sysctl_un.scu_idata
 #define sysctl_qdata   sysctl_un.scu_qdata
 
+/*
+ * when requesting a description of a node (a set of nodes, actually),
+ * you get back an "array" of these, where the actual length of the
+ * descr_str is noted in descr_len (which includes the trailing nul
+ * byte), rounded up to the nearest four (sizeof(int32_t) actually).
+ *
+ * NEXT_DESCR() will take a pointer to a description and advance it to
+ * the next description.
+ */
+struct sysctldesc {
+       int32_t         descr_num;      /* mib number of node */
+       uint32_t        descr_ver;      /* version of node */
+       uint32_t        descr_len;      /* length of description string */
+       char            descr_str[1];   /* not really 1...see above */
+};
+
+#define __sysc_desc_roundup(x) ((((x) - 1) | (sizeof(int32_t) - 1)) + 1)
+#define __sysc_desc_adv(d, l) \
+       (((const char*)(d)) + offsetof(struct sysctldesc, descr_str) + \
+               __sysc_desc_roundup(l))
+#define NEXT_DESCR(d) ((struct sysctldesc *) \
+       __sysc_desc_adv((d), (d)->descr_len))
+
 static __inline struct sysctlnode *
 sysctl_rootof(struct sysctlnode *n)
 {