platform_system_core/liblog/uio.c

77 lines
1.9 KiB
C

/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef HAVE_SYS_UIO_H
#include <log/uio.h>
#include <unistd.h>
int readv( int fd, struct iovec* vecs, int count )
{
int total = 0;
for ( ; count > 0; count--, vecs++ ) {
const char* buf = vecs->iov_base;
int len = vecs->iov_len;
while (len > 0) {
int ret = read( fd, buf, len );
if (ret < 0) {
if (total == 0)
total = -1;
goto Exit;
}
if (ret == 0)
goto Exit;
total += ret;
buf += ret;
len -= ret;
}
}
Exit:
return total;
}
int writev( int fd, const struct iovec* vecs, int count )
{
int total = 0;
for ( ; count > 0; count--, vecs++ ) {
const char* buf = (const char*)vecs->iov_base;
int len = (int)vecs->iov_len;
while (len > 0) {
int ret = write( fd, buf, len );
if (ret < 0) {
if (total == 0)
total = -1;
goto Exit;
}
if (ret == 0)
goto Exit;
total += ret;
buf += ret;
len -= ret;
}
}
Exit:
return total;
}
#endif /* !HAVE_SYS_UIO_H */