kolibrios/programs/develop/libraries/newlib/reent/writer.c
Sergey Semyonov (Serge) 0a3f4b2193 Newlib source code
git-svn-id: svn://kolibrios.org@1693 a494cfbc-eb01-0410-851d-a64ba20cac60
2010-11-07 13:42:29 +00:00

258 lines
6.9 KiB
C

/* Reentrant versions of write system call. */
#include <reent.h>
#include <unistd.h>
#include <_syslist.h>
#include <alloca.h>
#include <errno.h>
#include <string.h>
/* Some targets provides their own versions of this functions. Those
targets should define REENTRANT_SYSCALLS_PROVIDED in TARGET_CFLAGS. */
#ifdef _REENT_ONLY
#ifndef REENTRANT_SYSCALLS_PROVIDED
#define REENTRANT_SYSCALLS_PROVIDED
#endif
#endif
#ifndef REENTRANT_SYSCALLS_PROVIDED
/* We use the errno variable used by the system dependent layer. */
/*
FUNCTION
<<_write_r>>---Reentrant version of write
INDEX
_write_r
ANSI_SYNOPSIS
#include <reent.h>
_ssize_t _write_r(struct _reent *<[ptr]>,
int <[fd]>, const void *<[buf]>, size_t <[cnt]>);
TRAD_SYNOPSIS
#include <reent.h>
_ssize_t _write_r(<[ptr]>, <[fd]>, <[buf]>, <[cnt]>)
struct _reent *<[ptr]>;
int <[fd]>;
char *<[buf]>;
size_t <[cnt]>;
DESCRIPTION
This is a reentrant version of <<write>>. It
takes a pointer to the global data block, which holds
<<errno>>.
*/
#define _WRITE 0x0002 /* file opened for writing */
#define _APPEND 0x0080 /* file opened for append */
#define _BINARY 0x0040 /* file is binary, skip CRLF processing */
#define _ISTTY 0x2000 /* is console device */
#define _FILEEXT 0x8000 /* lseek with positive offset has been done */
#define __handle_check( __h, __r ) \
if( (__h) < 0 || (__h) > __NFiles ) { \
ptr->_errno = EBADF; \
return( __r ); \
}
extern unsigned __NFiles;
#define PAD_SIZE 512
static int zero_pad(struct _reent *ptr, int handle ) /* 09-jan-95 */
/*******************************/
{
int rc;
long curPos, eodPos;
long bytesToWrite;
unsigned writeAmt;
char zeroBuf[PAD_SIZE];
// Pad with zeros due to lseek() past EOF (POSIX)
curPos = _lseek_r( ptr, handle, 0L, SEEK_CUR ); /* current offset */
if( curPos == -1 )
return( -1 );
eodPos = _lseek_r( ptr, handle, 0L, SEEK_END ); /* end of data offset */
if( eodPos == -1 )
return( -1 );
if( curPos > eodPos ) {
bytesToWrite = curPos - eodPos; /* amount to pad by */
if( bytesToWrite > 0 ) { /* only write if needed */
memset( zeroBuf, 0x00, PAD_SIZE ); /* zero out a buffer */
do { /* loop until done */
if( bytesToWrite > PAD_SIZE )
writeAmt = 512;
else
writeAmt = (unsigned)bytesToWrite;
rc = _write_r(ptr, handle, zeroBuf, writeAmt );
if( rc < 0 )
return( rc );
bytesToWrite -= writeAmt; /* more bytes written */
} while( bytesToWrite != 0 );
}
} else {
curPos = _lseek_r( ptr, handle, curPos, SEEK_SET );
if( curPos == -1 ) {
return( -1 );
}
}
return( 0 ); /* return success code */
}
static int os_write(struct _reent *ptr, int handle,
const void *buffer, unsigned len, unsigned *amt )
/********************************************************************************/
{
__file_handle *fh;
int rc;
rc = 0;
*amt = 0;
fh = (__file_handle*) __getOSHandle( handle );
rc = fh->write(fh->name,buffer,fh->offset,len,amt);
fh->offset+= *amt;
if( *amt != len )
{
rc = ENOSPC;
ptr->_errno = ENOSPC;
}
return( rc );
}
_ssize_t
_DEFUN (_write_r, (ptr, fd, buffer, cnt),
struct _reent *ptr _AND
int fd _AND
_CONST _PTR buffer _AND
size_t cnt)
{
_ssize_t ret;
unsigned int iomode_flags;
unsigned len_written, i, j;
int rc2;
char *buf;
__file_handle *fh;
__handle_check( fd, -1 );
iomode_flags = __GetIOMode( fd );
if( iomode_flags == 0 )
{
ptr->_errno = EBADF;
return( -1 );
}
if( !(iomode_flags & _WRITE) ) {
ptr->_errno = EACCES ; /* changed from EBADF to EACCES 23-feb-89 */
return( -1 );
}
if( (iomode_flags & _APPEND) && !(iomode_flags & _ISTTY) )
{
fh->offset = _lseek_r(ptr, fd, 0L, SEEK_END ); /* end of data offset */
}
len_written = 0;
rc2 = 0;
// Pad the file with zeros if necessary
if( iomode_flags & _FILEEXT )
{
// turn off file extended flag
__SetIOMode_nogrow( fd, iomode_flags&(~_FILEEXT) );
// It is not required to pad a file with zeroes on an NTFS file system;
// unfortunately it is required on FAT (and probably FAT32). (JBS)
rc2 = zero_pad( ptr, fd );
}
if( rc2 == 0 )
{
if( iomode_flags & _BINARY ) { /* if binary mode */
rc2 = os_write(ptr, fd, buffer, cnt, &len_written );
/* end of binary mode part */
} else { /* text mode */
int buf_size = 512;
buf = (char*)alloca( buf_size );
j = 0;
for( i = 0; i < cnt; )
{
if( ((const char*)buffer)[i] == '\n' )
{
buf[j] = '\r';
++j;
if( j == buf_size )
{
rc2 = os_write(ptr, fd, buf, buf_size, &j );
if( rc2 == -1 )
break;
len_written += j;
if( rc2 == ENOSPC )
break;
len_written = i;
j = 0;
}
}
buf[j] = ((const char*)buffer)[i];
++i;
++j;
if( j == buf_size ) {
rc2 = os_write(ptr, fd, buf, buf_size, &j );
if( rc2 == -1 )
break;
len_written += j;
if( rc2 == ENOSPC )
break;
len_written = i;
j = 0;
}
}
if( j ) {
rc2 = os_write(ptr, fd, buf, j, &i );
if( rc2 == ENOSPC ) {
len_written += i;
} else {
len_written = cnt;
}
}
/* end of text mode part */
}
}
if( rc2 == -1 ) {
return( rc2 );
} else {
return( len_written );
}
}
_ssize_t
_DEFUN (write, ( fd, buffer, cnt),
int fd _AND
_CONST _PTR buffer _AND
size_t cnt)
{
return _write_r(_REENT, fd, buffer, cnt);
}
#endif /* ! defined (REENTRANT_SYSCALLS_PROVIDED) */