[src/trunk]: src/lib/libc/stdlib Restore the behaviour of not setting errno t...

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

details:   https://anonhg.NetBSD.org/src/rev/60db36d650f6
branches:  trunk
changeset: 476240:60db36d650f6
user:      kleink <kleink%NetBSD.org@localhost>
date:      Fri Sep 10 10:38:06 1999 +0000

description:
Restore the behaviour of not setting errno to ENOMEM when allocating 0
units of storage and returning a null pointer in System V mode; this was
broken by the `fix' in rev. 1.24.  Also, as it is stated in ISO C that
such operation does not constitute an allocation failure, do not abort()
even if the `X' option is set.

Amusingly enough the SVID, Fourth Edition, specifies the `unique pointer'
return behaviour for this kind of allocation, so this is kind of mis-named.

diffstat:

 lib/libc/stdlib/malloc.3 |  5 +----
 lib/libc/stdlib/malloc.c |  6 +++---
 2 files changed, 4 insertions(+), 7 deletions(-)

diffs (46 lines):

diff -r 7a8a02569af7 -r 60db36d650f6 lib/libc/stdlib/malloc.3
--- a/lib/libc/stdlib/malloc.3  Fri Sep 10 10:12:09 1999 +0000
+++ b/lib/libc/stdlib/malloc.3  Fri Sep 10 10:38:06 1999 +0000
@@ -1,4 +1,4 @@
-.\"    $NetBSD: malloc.3,v 1.10 1999/08/02 03:18:47 lukem Exp $
+.\"    $NetBSD: malloc.3,v 1.11 1999/09/10 10:38:06 kleink Exp $
 .\"
 .\" Copyright (c) 1980, 1991, 1993
 .\"    The Regents of the University of California.  All rights reserved.
@@ -207,9 +207,6 @@
 (The default behavior is to make a minimal allocation and return a 
 pointer to it.)
 This option is provided for System V compatibility.
-This option is incompatible with the
-.Dq X
-option.
 .It X
 Rather than return failure for any allocation function,
 display a diagnostic message on stderr and cause the program to drop
diff -r 7a8a02569af7 -r 60db36d650f6 lib/libc/stdlib/malloc.c
--- a/lib/libc/stdlib/malloc.c  Fri Sep 10 10:12:09 1999 +0000
+++ b/lib/libc/stdlib/malloc.c  Fri Sep 10 10:38:06 1999 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: malloc.c,v 1.25 1999/08/22 12:54:03 kleink Exp $       */
+/*     $NetBSD: malloc.c,v 1.26 1999/09/10 10:38:06 kleink Exp $       */
 
 /*
  * ----------------------------------------------------------------------------
@@ -1083,7 +1083,7 @@
     UTRACE(0, size, r);
     malloc_active--;
     THREAD_UNLOCK();
-    if (r == NULL) {
+    if (r == NULL && (size != 0 || !malloc_sysv)) {
        if (malloc_xmalloc)
            wrterror("out of memory.\n");
        errno = ENOMEM;
@@ -1138,7 +1138,7 @@
     UTRACE(ptr, size, r);
     malloc_active--;
     THREAD_UNLOCK();
-    if (r == NULL) {
+    if (r == NULL && (size != 0 || !malloc_sysv)) {
        if (malloc_xmalloc)
            wrterror("out of memory.\n");
        errno = ENOMEM;