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authorJim Meyering <jim@meyering.net>1994-01-26 18:46:41 +0000
committerJim Meyering <jim@meyering.net>1994-01-26 18:46:41 +0000
commitf1adf86d0987a704b8bebffc91bdddbbd886e8ee (patch)
tree9da62d522aa8ea4784b6193aa05489d61dfef912 /lib/safe-read.c
parent63e9766256432fc1099d822abe86606963c78a0b (diff)
downloadcoreutils-f1adf86d0987a704b8bebffc91bdddbbd886e8ee.tar.xz
merge with 3.9c
Diffstat (limited to 'lib/safe-read.c')
-rw-r--r--lib/safe-read.c71
1 files changed, 53 insertions, 18 deletions
diff --git a/lib/safe-read.c b/lib/safe-read.c
index d915d4e7c..2303ea111 100644
--- a/lib/safe-read.c
+++ b/lib/safe-read.c
@@ -1,4 +1,43 @@
-/* Read LEN bytes at PTR from descriptor DESC, retrying if necessary.
+/* safe-read.c -- an interface to read that retries after interrupts
+ Copyright (C) 1993, 1994 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+#ifdef HAVE_CONFIG_H
+#if defined (CONFIG_BROKETS)
+/* We use <config.h> instead of "config.h" so that a compilation
+ using -I. -I$srcdir will use ./config.h rather than $srcdir/config.h
+ (which it would do because it found this file in $srcdir). */
+#include <config.h>
+#else
+#include "config.h"
+#endif
+#endif
+
+#include <sys/types.h>
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include <errno.h>
+#ifndef STDC_HEADERS
+extern int errno;
+#endif
+
+/* Read LEN bytes at PTR from descriptor DESC, retrying if interrupted.
Return the actual number of bytes read, zero for EOF, or negative
for an error. */
@@ -8,24 +47,20 @@ safe_read (desc, ptr, len)
char *ptr;
int len;
{
- int n_remaining;
+ int n_chars;
+
+ if (len <= 0)
+ return len;
- n_remaining = len;
- while (n_remaining > 0)
- {
- int n_chars = read (desc, ptr, n_remaining);
- if (n_chars < 0)
- {
#ifdef EINTR
- if (errno == EINTR)
- continue;
-#endif
- return n_chars;
- }
- if (n_chars == 0)
- break;
- ptr += n_chars;
- n_remaining -= n_chars;
+ do
+ {
+ n_chars = read (desc, ptr, len);
}
- return len - n_remaining;
+ while (n_chars < 0 && errno == EINTR);
+#else
+ n_chars = read (desc, ptr, len);
+#endif
+
+ return n_chars;
}