#
# STDIO/FWRITE.D - output
#

public method
size_t
File.fwrite(void *buf, size_t bytes)
{
	size_t r = 0;

	# If a regular file requires a flush prior to turn-around to
	# ensure that any read-back sees the write.
	#
	if (this.flags & F_ISREG) {
		if ((this.flags & F_OUT) == 0) {
			this.flags |= F_OUT;
			this.in.base = 0;
			this.in.index = 0;
		}
	}

	/*
	 * If unbuffered just write the data directly
	 * (we are guarenteed to be flushed and it doesn't
	 * matter if we are in input mode).
	 */
	while (this.mode == File.M_NONE) {
                size_t n = this.fs.write1(buf, bytes);
                if (n <= 0L) {
                        if (n < 0 && this.fs.error == Sys.EINTR)
                                continue;
                        return r;               # early return
                }
                buf = (char *)buf + n;
                r += n;
		bytes -= n;
                this.pos += (off_t)n;
	}

	/*
	 * If we need an output buffer create one
	 */
	if (this.out.buf == NULL) {
		this.out.initbuf();
	}

	/*
	 * Copy to the buffer until the buffer is full
	 */
	while (bytes != 0L) {
		size_t n = this.out.size - this.out.index;

		if (n == 0L) {
			if (this.fflush() < 0)
				break;
			continue;
		}
		if (n > bytes)
			n = bytes;
		Sys.bcopy((char *)buf + r,
			  &this.out.buf[this.out.index], n);
		r += n;
		bytes -= n;
		this.pos += (off_t)n;
		this.out.index += n;
	}

	/*
	 * Line mode flush
	 */
	if (this.mode == File.M_LINE &&
		this.out.index != 0L &&
		this.out.buf[this.out.index - 1L] == '\n'
	) {
		int r2;

		if ((r2 = this.fflush()) < 0)
			r = (size_t)r2;
	}
	return(r);
}

public method
int
File.fputc(char c)
{
	if (this.mode == File.M_NONE) {
		if (this.fs.write(&c, 1) == 1L) {
			++this.pos;
			return(0);
		}
		return(-1);
	}

	/*
	 * If we need an output buffer create one
	 */
	if (this.out.buf == NULL)
		this.out.initbuf();

	/*
	 * Copy data to buffer
	 */
	if (this.out.index == this.out.size) {
		if (this.fflush() < 0)
			return(-1);
	}
	this.out.buf[this.out.index] = c;
	++this.out.index;
	++this.pos;

	/*
	 * Line mode flush
	 */
	if (this.mode == File.M_LINE && c == '\n')
		return(this.fflush());
	else
		return(0);
}

public method
int
File.fflush()
{
	size_t r = 0;

	if (this.out.index != 0L) {
		while (r != this.out.index) {
			size_t n;

			n = this.fs.write(&this.out.buf[0] + r,
					  this.out.index - r);
			if (n < 0L)
				return((int)n);
			r += n;
		}
		if (r != 0L && r != this.out.index) {
			Sys.bcopy(&this.out.buf[r], &this.out.buf[0],
				  this.out.index - r);
		}
		this.out.index -= r;
	}
	return(0);
}