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-rw-r--r--sysdeps/posix/writev.c42
1 files changed, 20 insertions, 22 deletions
diff --git a/sysdeps/posix/writev.c b/sysdeps/posix/writev.c
index a347cc2eac..203cf9cebd 100644
--- a/sysdeps/posix/writev.c
+++ b/sysdeps/posix/writev.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 1992, 1996, 1997, 2002 Free Software Foundation, Inc.
+/* Copyright (C) 1991,1992,1996,1997,2002,2009 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -25,24 +25,25 @@
#include <sys/uio.h>
#include <errno.h>
+
+static void
+ifree (char **ptrp)
+{
+ free (*ptrp);
+}
+
+
/* Write data pointed by the buffers described by VECTOR, which
- is a vector of COUNT `struct iovec's, to file descriptor FD.
+ is a vector of COUNT 'struct iovec's, to file descriptor FD.
The data is written in the order specified.
- Operates just like `write' (see <unistd.h>) except that the data
+ Operates just like 'write' (see <unistd.h>) except that the data
are taken from VECTOR instead of a contiguous buffer. */
ssize_t
__libc_writev (int fd, const struct iovec *vector, int count)
{
- char *buffer;
- register char *bp;
- size_t bytes, to_copy;
- ssize_t bytes_written;
- int i;
- bool use_malloc = false;
-
/* Find the total number of bytes to be written. */
- bytes = 0;
- for (i = 0; i < count; ++i)
+ size_t bytes = 0;
+ for (int i = 0; i < count; ++i)
{
/* Check for ssize_t overflow. */
if (SSIZE_MAX - bytes < vector[i].iov_len)
@@ -57,23 +58,23 @@ __libc_writev (int fd, const struct iovec *vector, int count)
use alloca since it's faster and does not require synchronization
with other threads. But we cannot if the amount of memory
required is too large. */
+ char *buffer;
+ char *malloced_buffer __attribute__ ((__cleanup__ (ifree))) = NULL;
if (__libc_use_alloca (bytes))
buffer = (char *) __alloca (bytes);
else
{
- buffer = (char *) malloc (bytes);
+ malloced_buffer = buffer = (char *) malloc (bytes);
if (buffer == NULL)
/* XXX I don't know whether it is acceptable to try writing
the data in chunks. Probably not so we just fail here. */
return -1;
-
- use_malloc = true;
}
/* Copy the data into BUFFER. */
- to_copy = bytes;
- bp = buffer;
- for (i = 0; i < count; ++i)
+ size_t to_copy = bytes;
+ char *bp = buffer;
+ for (int i = 0; i < count; ++i)
{
size_t copy = MIN (vector[i].iov_len, to_copy);
@@ -84,10 +85,7 @@ __libc_writev (int fd, const struct iovec *vector, int count)
break;
}
- bytes_written = __write (fd, buffer, bytes);
-
- if (use_malloc)
- free (buffer);
+ ssize_t bytes_written = __write (fd, buffer, bytes);
return bytes_written;
}