stdio

stdio

#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include "local.h"

/*
 * Small standard I/O/seek/close functions.
 * These maintain the `known seek offset' for seek optimisation.
 */
int
__sread(void *cookie, char *buf, int n)
{
	FILE *fp = cookie;
	int ret;
	
	ret = read(fp->_file, buf, n);
	/* if the read succeeded, update the current offset */
	if (ret >= 0)
		fp->_offset += ret;
	else
		fp->_flags &= ~__SOFF;	/* paranoia */
	return (ret);
}

int
__swrite(void *cookie, const char *buf, int n)
{
	FILE *fp = cookie;

	if (fp->_flags & __SAPP)
		(void) lseek(fp->_file, (off_t)0, SEEK_END);
	fp->_flags &= ~__SOFF;	/* in case FAPPEND mode is set */
	return (write(fp->_file, buf, n));
}

fpos_t
__sseek(void *cookie, fpos_t offset, int whence)
{
	FILE *fp = cookie;
	off_t ret;
	
	ret = lseek(fp->_file, (off_t)offset, whence);
	if (ret == (off_t)-1)
		fp->_flags &= ~__SOFF;
	else {
		fp->_flags |= __SOFF;
		fp->_offset = ret;
	}
	return (ret);
}

int
__sclose(void *cookie)
{
	return (close(((FILE *)cookie)->_file));
}