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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <mach.h>
include <config.h>
include "ki.h"
# KT_ZPUT -- Put a line of text to a text device. We are called only if the
# device does not reside on the local node. Output is buffered for greater
# bandwidth and efficiency.
procedure kt_zput (device, chan, ibuf, nchars, status)
int device # device driver code
int chan # channel assigned device
char ibuf[nchars] # receives text
int nchars # nchars to write
int status # receives nchars written or ERR
pointer bd, ep
include "kichan.com"
begin
bd = k_bufp[chan]
ep = B_RP(bd) + nchars - 1
# If this is the first write into the buffer, OTOP will be set to
# the beginning of the buffer and we must reset it to the end.
if (ep >= B_OTOP(bd)) {
# Check whether there is room remaining in the buffer for the data.
# We do not break output lines across buffer boundaries.
if (ep >= B_BUFTOP(bd)) {
call ki_flushtx (device, chan, status)
if (status == ERR)
return
# Check for buffer too small to hold data record. This should
# not be possible if SZ_TXBUF is chosen large enough, because
# FIO will break records larger than the FIO buffer size.
if (nchars > SZ_TXBUF) {
status = ERR
return
}
}
B_OTOP(bd) = B_BUFTOP(bd)
}
# Append the text data to the output buffer.
call amovc (ibuf, Memc[B_RP(bd)], nchars)
B_RP(bd) = B_RP(bd) + nchars
status = nchars
end
# KI_FLUSHTX -- Flush any buffered output of a text file. Text output is
# transmitted as a stream without reading the status back after each write.
# If a write error occurs on the logical channel to the text file, the kernel
# server will shut down entirely, causing a write error on the physical
# channel to the kernel server. It is harmless if we are called when the
# output buffer is empty or contains input data.
procedure ki_flushtx (device, chan, status)
int device # text file device code
int chan # channel assigned device
int status # receives nchars written or ERR
pointer bd, bp
int server, nchars
int ki_send()
include "kichan.com"
include "kii.com"
begin
bd = k_bufp[chan]
bp = B_BUFPTR(bd)
# OTOP will have been set to BUFTOP if the buffer was written into.
# RP may be greater than BUFPTR for input buffers, too. If there is
# nothing to flush return without taking any action and without
# changing any file pointers.
nchars = min (B_OTOP(bd), B_RP(bd)) - bp
if (nchars <= 0) {
status = 0
return
}
server = k_node[chan]
p_arg[1] = k_oschan[chan]
p_arg[2] = nchars
# If the buffer is small enough it is sent in the string buffer,
# otherwise it is sent as a second record.
if (nchars <= SZ_SBUF) {
call amovc (Memc[bp], p_sbuf, nchars)
p_sbuflen = nchars
} else
p_sbuflen = 0
# Send packet.
if (ki_send (server, device, TX_PUT) == ERR)
status = ERR
else if (nchars > SZ_SBUF) {
# Send data record.
call chrpak (Memc[bp], 1, Memc[bp], 1, nchars)
call ks_awrite (server, Memc[bp], nchars)
call ks_await (server, status)
if (status != nchars)
status = ERR
}
# Mark the buffer empty.
B_RP(bd) = bp
B_ITOP(bd) = bp
B_OTOP(bd) = bp
end
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