__swsetup: set error flag and errno on error.

Previously, we set errno to EBADF if the cantwrite() macro (which calls
__swsetup()) returns true for POSIX compliance.  However, we neglected
to also set the error flag, __SERR.  Rather than set the error flag in
all callers of cantwrite(), set both errno and the error flag in
__swsetup().  This matches what FreeBSD does and makes it possible
to choose a proper errno value for the second error condition in
__swsetup().  OK deraadt@

diff --git a/lib/libc/stdio/fvwrite.c b/lib/libc/stdio/fvwrite.c
index ba58f9d..d83de88 100644 (file)
--- a/lib/libc/stdio/fvwrite.c
+++ b/lib/libc/stdio/fvwrite.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: fvwrite.c,v 1.20 2017/03/17 16:06:33 millert Exp $ */
+/*     $OpenBSD: fvwrite.c,v 1.21 2023/10/06 16:41:02 millert Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *     The Regents of the University of California.  All rights reserved.
@@ -34,7 +34,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <errno.h>
 #include <unistd.h>
 #include "local.h"
 #include "fvwrite.h"
@@ -58,10 +57,8 @@ __sfvwrite(FILE *fp, struct __suio *uio)
        if ((len = uio->uio_resid) == 0)
                return (0);
        /* make sure we can write */
-       if (cantwrite(fp)) {
-               errno = EBADF;
+       if (cantwrite(fp))
                return (EOF);
-       }
 
 #define        MIN(a, b) ((a) < (b) ? (a) : (b))
 #define        COPY(n)   (void)memcpy(fp->_p, p, n)

diff --git a/lib/libc/stdio/putc.c b/lib/libc/stdio/putc.c
index 9fca905..b58ae73 100644 (file)
--- a/lib/libc/stdio/putc.c
+++ b/lib/libc/stdio/putc.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: putc.c,v 1.13 2015/08/31 02:53:57 guenther Exp $ */
+/*     $OpenBSD: putc.c,v 1.14 2023/10/06 16:41:02 millert Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *     The Regents of the University of California.  All rights reserved.
@@ -32,7 +32,6 @@
  */
 
 #include <stdio.h>
-#include <errno.h>
 #include "local.h"
 
 /*
@@ -43,10 +42,8 @@
 int
 putc_unlocked(int c, FILE *fp)
 {
-       if (cantwrite(fp)) {
-               errno = EBADF;
+       if (cantwrite(fp))
                return (EOF);
-       }
        _SET_ORIENTATION(fp, -1);
        return (__sputc(c, fp));
 }

diff --git a/lib/libc/stdio/vfprintf.c b/lib/libc/stdio/vfprintf.c
index 9c684c8..759aab5 100644 (file)
--- a/lib/libc/stdio/vfprintf.c
+++ b/lib/libc/stdio/vfprintf.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vfprintf.c,v 1.81 2021/09/08 15:57:27 jca Exp $       */
+/*     $OpenBSD: vfprintf.c,v 1.82 2023/10/06 16:41:02 millert Exp $   */
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -457,10 +457,8 @@ __vfprintf(FILE *fp, const char *fmt0, __va_list ap)
 
        _SET_ORIENTATION(fp, -1);
        /* sorry, fprintf(read_only_file, "") returns EOF, not 0 */
-       if (cantwrite(fp)) {
-               errno = EBADF;
+       if (cantwrite(fp))
                return (EOF);
-       }
 
        /* optimise fprintf(stderr) (and other unbuffered Unix files) */
        if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&

diff --git a/lib/libc/stdio/vfwprintf.c b/lib/libc/stdio/vfwprintf.c
index c6db189..f968ebb 100644 (file)
--- a/lib/libc/stdio/vfwprintf.c
+++ b/lib/libc/stdio/vfwprintf.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vfwprintf.c,v 1.22 2021/09/08 15:57:27 jca Exp $ */
+/*     $OpenBSD: vfwprintf.c,v 1.23 2023/10/06 16:41:02 millert Exp $ */
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -451,10 +451,8 @@ __vfwprintf(FILE * __restrict fp, const wchar_t * __restrict fmt0, __va_list ap)
 
        _SET_ORIENTATION(fp, 1);
        /* sorry, fwprintf(read_only_file, "") returns EOF, not 0 */
-       if (cantwrite(fp)) {
-               errno = EBADF;
+       if (cantwrite(fp))
                return (EOF);
-       }
 
        /* optimise fwprintf(stderr) (and other unbuffered Unix files) */
        if ((fp->_flags & (__SNBF|__SWR|__SRW)) == (__SNBF|__SWR) &&

diff --git a/lib/libc/stdio/wbuf.c b/lib/libc/stdio/wbuf.c
index 2d07750..edb6a50 100644 (file)
--- a/lib/libc/stdio/wbuf.c
+++ b/lib/libc/stdio/wbuf.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: wbuf.c,v 1.13 2015/08/31 02:53:57 guenther Exp $ */
+/*     $OpenBSD: wbuf.c,v 1.14 2023/10/06 16:41:02 millert Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *     The Regents of the University of California.  All rights reserved.
@@ -32,7 +32,6 @@
  */
 
 #include <stdio.h>
-#include <errno.h>
 #include "local.h"
 
 /*
@@ -54,10 +53,8 @@ __swbuf(int c, FILE *fp)
         * calls might wrap _w from negative to positive.
         */
        fp->_w = fp->_lbfsize;
-       if (cantwrite(fp)) {
-               errno = EBADF;
+       if (cantwrite(fp))
                return (EOF);
-       }
        c = (unsigned char)c;
 
        /*

diff --git a/lib/libc/stdio/wsetup.c b/lib/libc/stdio/wsetup.c
index 0834223..842036b 100644 (file)
--- a/lib/libc/stdio/wsetup.c
+++ b/lib/libc/stdio/wsetup.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: wsetup.c,v 1.7 2005/08/08 08:05:36 espie Exp $ */
+/*     $OpenBSD: wsetup.c,v 1.8 2023/10/06 16:41:02 millert Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *     The Regents of the University of California.  All rights reserved.
@@ -31,6 +31,7 @@
  * SUCH DAMAGE.
  */
 
+#include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include "local.h"
@@ -38,7 +39,7 @@
 /*
  * Various output routines call wsetup to be sure it is safe to write,
  * because either _flags does not include __SWR, or _buf is NULL.
- * _wsetup returns 0 if OK to write, nonzero otherwise.
+ * __swsetup returns 0 if OK to write, nonzero otherwise, setting errno.
  */
 int
 __swsetup(FILE *fp)
@@ -51,8 +52,11 @@ __swsetup(FILE *fp)
         * If we are not writing, we had better be reading and writing.
         */
        if ((fp->_flags & __SWR) == 0) {
-               if ((fp->_flags & __SRW) == 0)
+               if ((fp->_flags & __SRW) == 0) {
+                       errno = EBADF;
+                       fp->_flags |= __SERR;
                        return (EOF);
+               }
                if (fp->_flags & __SRD) {
                        /* clobber any ungetc data */
                        if (HASUB(fp))
@@ -68,8 +72,11 @@ __swsetup(FILE *fp)
         * Make a buffer if necessary, then set _w.
         */
        if (fp->_bf._base == NULL) {
-               if ((fp->_flags & (__SSTR | __SALC)) == __SSTR)
+               if ((fp->_flags & (__SSTR | __SALC)) == __SSTR) {
+                       errno = EINVAL;
+                       fp->_flags |= __SERR;
                        return (EOF);
+               }
                __smakebuf(fp);
        }
        if (fp->_flags & __SLBF) {