Mon Jul 19 10:00:33 2021 UTC ()
There's no need to adjust `iov' in the error path.
Returning the amount written is all that's needed.
from RVP


(christos)
diff -r1.28 -r1.29 src/lib/libc/stdio/fvwrite.c
cvs diff -r1.28 -r1.29 src/lib/libc/stdio/fvwrite.c (expand / switch to unified diff)

--- src/lib/libc/stdio/fvwrite.c 2021/07/16 12:34:10 1.28
+++ src/lib/libc/stdio/fvwrite.c 2021/07/19 10:00:32 1.29
@@ -1,14 +1,14 @@ @@ -1,14 +1,14 @@
1/* $NetBSD: fvwrite.c,v 1.28 2021/07/16 12:34:10 christos Exp $ */ 1/* $NetBSD: fvwrite.c,v 1.29 2021/07/19 10:00:32 christos Exp $ */
2 2
3/*- 3/*-
4 * Copyright (c) 1990, 1993 4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved. 5 * The Regents of the University of California. All rights reserved.
6 * 6 *
7 * This code is derived from software contributed to Berkeley by 7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek. 8 * Chris Torek.
9 * 9 *
10 * Redistribution and use in source and binary forms, with or without 10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions 11 * modification, are permitted provided that the following conditions
12 * are met: 12 * are met:
13 * 1. Redistributions of source code must retain the above copyright 13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer. 14 * notice, this list of conditions and the following disclaimer.
@@ -27,64 +27,63 @@ @@ -27,64 +27,63 @@
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE. 32 * SUCH DAMAGE.
33 */ 33 */
34 34
35#include <sys/cdefs.h> 35#include <sys/cdefs.h>
36#if defined(LIBC_SCCS) && !defined(lint) 36#if defined(LIBC_SCCS) && !defined(lint)
37#if 0 37#if 0
38static char sccsid[] = "@(#)fvwrite.c 8.1 (Berkeley) 6/4/93"; 38static char sccsid[] = "@(#)fvwrite.c 8.1 (Berkeley) 6/4/93";
39#else 39#else
40__RCSID("$NetBSD: fvwrite.c,v 1.28 2021/07/16 12:34:10 christos Exp $"); 40__RCSID("$NetBSD: fvwrite.c,v 1.29 2021/07/19 10:00:32 christos Exp $");
41#endif 41#endif
42#endif /* LIBC_SCCS and not lint */ 42#endif /* LIBC_SCCS and not lint */
43 43
44#include <assert.h> 44#include <assert.h>
45#include <stddef.h> 45#include <stddef.h>
46#include <errno.h> 46#include <errno.h>
47#include <stdio.h> 47#include <stdio.h>
48#include <stdlib.h> 48#include <stdlib.h>
49#include <string.h> 49#include <string.h>
50#include "reentrant.h" 50#include "reentrant.h"
51#include "local.h" 51#include "local.h"
52#include "fvwrite.h" 52#include "fvwrite.h"
53 53
54static int 54static int
55flush_adj(FILE *fp, struct __suio *uio, struct __siov *iov, ssize_t w) 55flush_adj(FILE *fp, struct __suio *uio, ssize_t w)
56{ 56{
57 int rc; 57 int rc;
58 58
59 _DIAGASSERT(w >= 0); 59 _DIAGASSERT(w >= 0);
60 _DIAGASSERT(fp->_w >= 0); 60 _DIAGASSERT(fp->_w >= 0);
61 61
62 if ((rc = fflush(fp)) == 0) 62 if ((rc = fflush(fp)) == 0)
63 return 0; 63 return 0;
64 64
65 /* 65 /*
66 * If we have to return without writing the whole buffer, 66 * If we have to return without writing the whole buffer,
67 * adjust for how much fflush() has written for us. 67 * adjust for how much fflush() has written for us.
68 * `w' is the amt. of new user data just copied into our 68 * `w' is the amt. of new user data just copied into our
69 * internal buffer in _this_ fwrite() call. 69 * internal buffer in _this_ fwrite() call.
70 */ 70 */
71 if (fp->_w < w) { 71 if (fp->_w < w) {
72 /* some new data was also written */ 72 /* some new data was also written */
73 ssize_t i = w - fp->_w; 73 ssize_t i = w - fp->_w;
74 74
75 /* adjust amt. written */ 75 /* adjust amt. written */
76 uio->uio_resid -= i; 76 uio->uio_resid -= i;
77 iov->iov_len -= i; 
78 } else { 77 } else {
79 /* only old stuff was written */ 78 /* only old stuff was written */
80 79
81 /* adjust _p and _w so user can retry */ 80 /* adjust _p and _w so user can retry */
82 fp->_p -= w; 81 fp->_p -= w;
83 fp->_w += w; 82 fp->_w += w;
84 } 83 }
85 return rc; 84 return rc;
86} 85}
87 86
88/* 87/*
89 * Write some memory regions. Return zero on success, EOF on error. 88 * Write some memory regions. Return zero on success, EOF on error.
90 * 89 *
@@ -126,27 +125,27 @@ __sfvwrite(FILE *fp, struct __suio *uio) @@ -126,27 +125,27 @@ __sfvwrite(FILE *fp, struct __suio *uio)
126 iov++; 125 iov++;
127#define GETIOV(extra_work) \ 126#define GETIOV(extra_work) \
128 while (len == 0) { \ 127 while (len == 0) { \
129 extra_work; \ 128 extra_work; \
130 p = iov->iov_base; \ 129 p = iov->iov_base; \
131 len = iov->iov_len; \ 130 len = iov->iov_len; \
132 iov++; \ 131 iov++; \
133 } 132 }
134#define WRITE(nw) \ 133#define WRITE(nw) \
135 w = (*fp->_write)(fp->_cookie, p, nw); \ 134 w = (*fp->_write)(fp->_cookie, p, nw); \
136 if (w <= 0) \ 135 if (w <= 0) \
137 goto err 136 goto err
138#define FLUSH(nw) \ 137#define FLUSH(nw) \
139 if (flush_adj(fp, uio, iov - 1, nw)) \ 138 if (flush_adj(fp, uio, nw)) \
140 goto err 139 goto err
141 140
142 if (fp->_flags & __SNBF) { 141 if (fp->_flags & __SNBF) {
143 /* 142 /*
144 * Unbuffered: write up to BUFSIZ bytes at a time. 143 * Unbuffered: write up to BUFSIZ bytes at a time.
145 */ 144 */
146 do { 145 do {
147 GETIOV(;); 146 GETIOV(;);
148 WRITE(MIN(len, BUFSIZ)); 147 WRITE(MIN(len, BUFSIZ));
149 p += w; 148 p += w;
150 len -= w; 149 len -= w;
151 } while ((uio->uio_resid -= w) != 0); 150 } while ((uio->uio_resid -= w) != 0);
152 } else if ((fp->_flags & __SLBF) == 0) { 151 } else if ((fp->_flags & __SLBF) == 0) {