mirror of
				https://sourceware.org/git/glibc.git
				synced 2025-10-28 23:34:53 +03:00 
			
		
		
		
	
		
			
				
	
	
		
			77 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* writev supports all Linux kernels >= 2.0.
 | |
|    Copyright (C) 1997,1998,2000,2002,2003,2009 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
 | |
|    modify it under the terms of the GNU Lesser General Public
 | |
|    License as published by the Free Software Foundation; either
 | |
|    version 2.1 of the License, or (at your option) any later version.
 | |
| 
 | |
|    The GNU C Library 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
 | |
|    Lesser General Public License for more details.
 | |
| 
 | |
|    You should have received a copy of the GNU Lesser General Public
 | |
|    License along with the GNU C Library; if not, write to the Free
 | |
|    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 | |
|    02111-1307 USA.  */
 | |
| 
 | |
| #include <errno.h>
 | |
| #include <stddef.h>
 | |
| #include <sys/param.h>
 | |
| #include <sys/uio.h>
 | |
| 
 | |
| #include <sysdep-cancel.h>
 | |
| #include <sys/syscall.h>
 | |
| #include <bp-checks.h>
 | |
| #include <kernel-features.h>
 | |
| 
 | |
| #ifndef __ASSUME_COMPLETE_READV_WRITEV
 | |
| static ssize_t __atomic_writev_replacement (int, const struct iovec *,
 | |
| 					    int) internal_function;
 | |
| #endif
 | |
| 
 | |
| 
 | |
| /* Not all versions of the kernel support the large number of records.  */
 | |
| #ifndef UIO_FASTIOV
 | |
| # define UIO_FASTIOV	8	/* 8 is a safe number.  */
 | |
| #endif
 | |
| 
 | |
| 
 | |
| ssize_t
 | |
| __libc_writev (fd, vector, count)
 | |
|      int fd;
 | |
|      const struct iovec *vector;
 | |
|      int count;
 | |
| {
 | |
|   ssize_t result;
 | |
| 
 | |
|   if (SINGLE_THREAD_P)
 | |
|     result = INLINE_SYSCALL (writev, 3, fd, CHECK_N (vector, count), count);
 | |
|   else
 | |
|     {
 | |
|       int oldtype = LIBC_CANCEL_ASYNC ();
 | |
| 
 | |
|       result = INLINE_SYSCALL (writev, 3, fd, CHECK_N (vector, count), count);
 | |
| 
 | |
|       LIBC_CANCEL_RESET (oldtype);
 | |
|     }
 | |
| 
 | |
| #ifdef __ASSUME_COMPLETE_READV_WRITEV
 | |
|   return result;
 | |
| #else
 | |
|   if (result >= 0 || errno != EINVAL || count <= UIO_FASTIOV)
 | |
|     return result;
 | |
| 
 | |
|   return __atomic_writev_replacement (fd, vector, count);
 | |
| #endif
 | |
| }
 | |
| strong_alias (__libc_writev, __writev)
 | |
| weak_alias (__libc_writev, writev)
 | |
| 
 | |
| #ifndef __ASSUME_COMPLETE_READV_WRITEV
 | |
| # define __libc_writev static internal_function __atomic_writev_replacement
 | |
| # include <sysdeps/posix/writev.c>
 | |
| #endif
 |