Add the POSIX 1003.1-2001 posix_madvise() interface.

PR:		standards/54634
Reviewed by:	das
Approved by:	jake (mentor)

4 files changed, 29 insertions, 4 deletions

diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index 9ab8616..e26ed2f 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -19,7 +19,8 @@ SRCS+=  __xuname.c _pthread_stubs.c _rand48.c _spinlock_stub.c _thread_init.c \
 	initgroups.c isatty.c jrand48.c lcong48.c \
 	lockf.c lrand48.c mrand48.c nice.c \
 	nlist.c nrand48.c ntp_gettime.c opendir.c \
-	pause.c popen.c posixshm.c pselect.c psignal.c pw_scan.c pwcache.c \
+	pause.c pmadvise.c popen.c posixshm.c pselect.c \
+	psignal.c pw_scan.c pwcache.c \
 	raise.c readdir.c readpassphrase.c rewinddir.c \
 	scandir.c seed48.c seekdir.c semctl.c \
 	setdomainname.c sethostname.c setjmperr.c setmode.c \
diff --git a/lib/libc/gen/pmadvise.c b/lib/libc/gen/pmadvise.c
index 4024d64..60cef63 100644
--- a/lib/libc/gen/pmadvise.c
+++ b/lib/libc/gen/pmadvise.c
@@ -10,7 +10,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/mman.h>
 
 int
-(posix_madvise)(void *address, size_t size, int how)
+posix_madvise(void *address, size_t size, int how)
 {
-	return posix_madvise(address, size, how);
+	return madvise(address, size, how);
 }
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 0c53319..ae536d5 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -119,6 +119,7 @@ MLINKS+=jail.2 jail_attach.2
 MLINKS+=kqueue.2 kevent.2
 MLINKS+=kse.2 kse_create.2 kse.2 kse_exit.2 kse.2 kse_release.2 \
 	kse.2 kse_wakeup.2 kse.2 kse_thr_interrupt.2
+MLINKS+=madvise.2 posix_madvise.2
 MLINKS+=mlock.2 munlock.2
 MLINKS+=modnext.2 modfnext.2
 MLINKS+=mount.2 unmount.2
diff --git a/lib/libc/sys/madvise.2 b/lib/libc/sys/madvise.2
index d783ea0..25cb5c7 100644
--- a/lib/libc/sys/madvise.2
+++ b/lib/libc/sys/madvise.2
@@ -36,7 +36,7 @@
 .Dt MADVISE 2
 .Os
 .Sh NAME
-.Nm madvise
+.Nm madvise , posix_madvise
 .Nd give advice about use of memory
 .Sh LIBRARY
 .Lb libc
@@ -44,12 +44,17 @@
 .In sys/mman.h
 .Ft int
 .Fn madvise "void *addr" "size_t len" "int behav"
+.Ft int
+.Fn posix_madvise "void *addr" "size_t len" "int behav"
 .Sh DESCRIPTION
 The
 .Fn madvise
 system call
 allows a process that has knowledge of its memory behavior
 to describe it to the system.
+The
+.Fn posix_madvise
+interface is identical and is provided for standards conformance.
 .Pp
 The known behaviors are:
 .Bl -tag -width MADV_SEQUENTIAL
@@ -124,6 +129,15 @@ The process must have superuser privileges.
 This should be used judiciously in processes that must remain running
 for the system to properly function.
 .El
+.Pp
+Portable programs that call the
+.Fn posix_madvise
+interface should use the aliases
+.Dv POSIX_MADV_NORMAL , POSIX_MADV_SEQUENTIAL ,
+.Dv POSIX_MADV_RANDOM , POSIX_MADV_WILLNEED ,
+and
+.Dv POSIX_MADV_DONTNEED
+rather than the flags described above.
 .Sh RETURN VALUES
 .Rv -std madvise
 .Sh ERRORS
@@ -132,6 +146,10 @@ The
 system call will fail if:
 .Bl -tag -width Er
 .It Bq Er EINVAL
+The
+.Fa behav
+argument is not valid.
+.It Bq Er ENOMEM
 The virtual address range specified by the
 .Fa addr
 and
@@ -146,6 +164,11 @@ was specified and the process does not have superuser privileges.
 .Xr mprotect 2 ,
 .Xr msync 2 ,
 .Xr munmap 2
+.Sh STANDARDS
+The
+.Fn posix_madvise
+interface conforms to
+.St -p1003.1-2001 .
 .Sh HISTORY
 The
 .Fn madvise