/*
- * $Id: dsi_stream.c,v 1.20 2009-10-26 12:35:56 franklahm Exp $
- *
* Copyright (c) 1998 Adrian Sun (asun@zoology.washington.edu)
* All rights reserved. See COPYRIGHT.
*
#include "config.h"
#endif /* HAVE_CONFIG_H */
-#define USE_WRITEV
-
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
-
-#ifdef USE_WRITEV
#include <sys/uio.h>
-#endif
#include <atalk/logger.h>
#include <atalk/dsi.h>
-#include <netatalk/endian.h>
#include <atalk/util.h>
#define min(a,b) ((a) < (b) ? (a) : (b))
#define MSG_DONTWAIT 0x40
#endif
-/* -------------------------
- * we don't use a circular buffer.
-*/
-static void dsi_init_buffer(DSI *dsi)
-{
- if (!dsi->buffer) {
- /* XXX config options */
- dsi->maxsize = 6 * dsi->server_quantum;
- if (!dsi->maxsize)
- dsi->maxsize = 6 * DSI_SERVQUANT_DEF;
- dsi->buffer = malloc(dsi->maxsize);
- if (!dsi->buffer) {
- return;
- }
- dsi->start = dsi->buffer;
- dsi->eof = dsi->buffer;
- dsi->end = dsi->buffer + dsi->maxsize;
- }
-}
-
-/* ----------------------
- afpd is sleeping too much while trying to send something.
- May be there's no reader or the reader is also sleeping in write,
- look if there's some data for us to read, hopefully it will wake up
- the reader
-*/
-static int dsi_buffer(DSI *dsi)
+/*
+ * afpd is sleeping too much while trying to send something.
+ * May be there's no reader or the reader is also sleeping in write,
+ * look if there's some data for us to read, hopefully it will wake up
+ * the reader so we can write again.
+ *
+ * @returns 0 when is possible to send again, -1 on error
+ */
+static int dsi_peek(DSI *dsi)
{
+ static int warned = 0;
fd_set readfds, writefds;
int len;
int maxfd;
+ int ret;
- LOG(log_maxdebug, logtype_dsi, "dsi_buffer: switching to non-blocking IO");
+ LOG(log_debug, logtype_dsi, "dsi_peek");
+
+ maxfd = dsi->socket + 1;
- /* non blocking mode */
- if (setnonblock(dsi->socket, 1) < 0) {
- /* can't do it! exit without error it will sleep to death below */
- LOG(log_error, logtype_dsi, "dsi_buffer: ioctl non blocking mode %s", strerror(errno));
- return 0;
- }
-
- FD_ZERO(&readfds);
- FD_ZERO(&writefds);
- FD_SET( dsi->socket, &readfds);
- FD_SET( dsi->socket, &writefds);
- maxfd = dsi->socket +1;
while (1) {
- FD_SET( dsi->socket, &readfds);
+ FD_ZERO(&readfds);
+ FD_ZERO(&writefds);
+
+ if (dsi->eof < dsi->end) {
+ /* space in read buffer */
+ FD_SET( dsi->socket, &readfds);
+ } else {
+ if (!warned) {
+ warned = 1;
+ LOG(log_note, logtype_dsi, "dsi_peek: readahead buffer is full, possibly increase -dsireadbuf option");
+ LOG(log_note, logtype_dsi, "dsi_peek: dsireadbuf: %d, DSI quantum: %d, effective buffer size: %d",
+ dsi->dsireadbuf,
+ dsi->server_quantum ? dsi->server_quantum : DSI_SERVQUANT_DEF,
+ dsi->end - dsi->buffer);
+ }
+ }
+
FD_SET( dsi->socket, &writefds);
- if (select( maxfd, &readfds, &writefds, NULL, NULL) <= 0)
- break;
- if ( !FD_ISSET(dsi->socket, &readfds)) {
- /* nothing waiting in the read queue */
- break;
+ /* No timeout: if there's nothing to read nor nothing to write,
+ * we've got nothing to do at all */
+ if ((ret = select( maxfd, &readfds, &writefds, NULL, NULL)) <= 0) {
+ if (ret == -1 && errno == EINTR)
+ /* we might have been interrupted by out timer, so restart select */
+ continue;
+ /* give up */
+ LOG(log_error, logtype_dsi, "dsi_peek: unexpected select return: %d %s",
+ ret, ret < 0 ? strerror(errno) : "");
+ return -1;
}
- dsi_init_buffer(dsi);
- len = dsi->end - dsi->eof;
-
- if (len <= 0) {
- /* ouch, our buffer is full !
- * fall back to blocking IO
- * could block and disconnect but it's better than a cpu hog
- */
+
+ if (FD_ISSET(dsi->socket, &writefds)) {
+ /* we can write again */
+ LOG(log_debug, logtype_dsi, "dsi_peek: can write again");
break;
}
- len = read(dsi->socket, dsi->eof, len);
- if (len <= 0)
- break;
- dsi->eof += len;
- if ( FD_ISSET(dsi->socket, &writefds)) {
- /* we can write again at last */
- break;
+ /* Check if there's sth to read, hopefully reading that will unblock the client */
+ if (FD_ISSET(dsi->socket, &readfds)) {
+ len = dsi->end - dsi->eof; /* it's ensured above that there's space */
+
+ if ((len = read(dsi->socket, dsi->eof, len)) <= 0) {
+ if (len == 0) {
+ LOG(log_error, logtype_dsi, "dsi_peek: EOF");
+ return -1;
+ }
+ LOG(log_error, logtype_dsi, "dsi_peek: read: %s", strerror(errno));
+ if (errno == EAGAIN)
+ continue;
+ return -1;
+ }
+ LOG(log_debug, logtype_dsi, "dsi_peek: read %d bytes", len);
+
+ dsi->eof += len;
}
}
- LOG(log_maxdebug, logtype_dsi, "dsi_buffer: switching back to blocking IO");
-
- if (setnonblock(dsi->socket, 0) < 0) {
- /* can't do it! afpd will fail very quickly */
- LOG(log_error, logtype_dsi, "dsi_buffer: ioctl blocking mode %s", strerror(errno));
- return -1;
- }
return 0;
}
{
size_t written;
ssize_t len;
-#if 0
- /* FIXME sometime it's slower */
- unsigned int flags = (mode)?MSG_MORE:0;
-#endif
unsigned int flags = 0;
-#if 0
- /* XXX there's no MSG_DONTWAIT in recv ?? so we have to play with ioctl
- */
- flags |= MSG_DONTWAIT;
-#endif
-
dsi->in_write++;
written = 0;
while (written < length) {
len = send(dsi->socket, (u_int8_t *) data + written, length - written, flags);
- if ((len == 0) || (len == -1 && errno == EINTR))
+ if (len >= 0) {
+ written += len;
+ continue;
+ }
+
+ if (errno == EINTR)
continue;
- if (len < 0) {
if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ LOG(log_debug, logtype_dsi, "dsi_stream_write: send: %s", strerror(errno));
+
if (mode == DSI_NOWAIT && written == 0) {
/* DSI_NOWAIT is used by attention give up in this case. */
- return -1;
+ written = -1;
+ goto exit;
}
- if (dsi_buffer(dsi)) {
- /* can't go back to blocking mode, exit, the next read
- will return with an error and afpd will die.
- */
- break;
+
+ /* Try to read sth. in order to break up possible deadlock */
+ if (dsi_peek(dsi) != 0) {
+ written = -1;
+ goto exit;
}
+ /* Now try writing again */
continue;
}
+
LOG(log_error, logtype_dsi, "dsi_stream_write: %s", strerror(errno));
- break;
- }
- else {
- written += len;
- }
+ written = -1;
+ goto exit;
}
dsi->write_count += written;
+
+exit:
dsi->in_write--;
return written;
}
size_t written;
ssize_t len;
+ LOG(log_maxdebug, logtype_dsi, "dsi_stream_read_file: sending %u bytes", length);
+
dsi->in_write++;
written = 0;
return -1;
if (errno == EAGAIN || errno == EWOULDBLOCK) {
- if (dsi_buffer(dsi)) {
+ if (dsi_peek(dsi)) {
/* can't go back to blocking mode, exit, the next read
will return with an error and afpd will die.
*/
}
continue;
}
- LOG(log_error, logtype_dsi, "dsi_stream_write: %s", strerror(errno));
+ LOG(log_error, logtype_dsi, "dsi_stream_read_file: %s", strerror(errno));
break;
}
else if (!len) {
static size_t from_buf(DSI *dsi, u_int8_t *buf, size_t count)
{
size_t nbe = 0;
-
- if (dsi->start) {
- nbe = dsi->eof - dsi->start;
- if (nbe > 0) {
- nbe = min((size_t)nbe, count);
- memcpy(buf, dsi->start, nbe);
- dsi->start += nbe;
+ if (dsi->buffer == NULL)
+ /* afpd master has no DSI buffering */
+ return 0;
- if (dsi->eof == dsi->start)
- dsi->start = dsi->eof = dsi->buffer;
+ LOG(log_maxdebug, logtype_dsi, "from_buf: %u bytes", count);
+
+ nbe = dsi->eof - dsi->start;
- }
+ if (nbe > 0) {
+ nbe = min((size_t)nbe, count);
+ memcpy(buf, dsi->start, nbe);
+ dsi->start += nbe;
+
+ if (dsi->eof == dsi->start)
+ dsi->start = dsi->eof = dsi->buffer;
}
+
+ LOG(log_debug, logtype_dsi, "from_buf(read: %u, unread:%u , space left: %u): returning %u",
+ dsi->start - dsi->buffer, dsi->eof - dsi->start, dsi->end - dsi->eof, nbe);
+
return nbe;
}
*/
static ssize_t buf_read(DSI *dsi, u_int8_t *buf, size_t count)
{
- ssize_t nbe;
-
+ ssize_t len;
+
+ LOG(log_maxdebug, logtype_dsi, "buf_read(%u bytes)", count);
+
if (!count)
return 0;
- nbe = from_buf(dsi, buf, count); /* 1. */
- if (nbe)
- return nbe; /* 2. */
+ len = from_buf(dsi, buf, count); /* 1. */
+ if (len)
+ return len; /* 2. */
- return read(dsi->socket, buf, count); /* 3. */
+ len = readt(dsi->socket, buf, count, 0, 1); /* 3. */
+
+ LOG(log_maxdebug, logtype_dsi, "buf_read(%u bytes): got: %d", count, len);
+
+ return len;
}
/*
* Essentially a loop around buf_read() to ensure "length" bytes are read
* from dsi->buffer and/or the socket.
+ *
+ * @returns length on success, some value smaller then length indicates an error
*/
size_t dsi_stream_read(DSI *dsi, void *data, const size_t length)
{
size_t stored;
ssize_t len;
-
+
+ LOG(log_maxdebug, logtype_dsi, "dsi_stream_read(%u bytes)", length);
+
stored = 0;
while (stored < length) {
- len = buf_read(dsi, (u_int8_t *) data + stored, length - stored);
- if (len == -1 && errno == EINTR)
- continue;
- else if (len > 0)
- stored += len;
- else { /* eof or error */
- /* don't log EOF error if it's just after connect (OSX 10.3 probe) */
- if (len || stored || dsi->read_count) {
- LOG(log_error, logtype_dsi, "dsi_stream_read(%d): %s", len, (len < 0)?strerror(errno):"unexpected EOF");
+ len = buf_read(dsi, (u_int8_t *) data + stored, length - stored);
+ if (len == -1 && (errno == EINTR || errno == EAGAIN)) {
+ LOG(log_debug, logtype_dsi, "dsi_stream_read: select read loop");
+ continue;
+ } else if (len > 0) {
+ stored += len;
+ } else { /* eof or error */
+ /* don't log EOF error if it's just after connect (OSX 10.3 probe) */
+ if (len || stored || dsi->read_count) {
+ if (! (dsi->flags & DSI_DISCONNECTED)) {
+ LOG(log_error, logtype_dsi, "dsi_stream_read: len:%d, %s",
+ len, (len < 0) ? strerror(errno) : "unexpected EOF");
+ }
+ return 0;
+ }
+ break;
}
- break;
- }
}
dsi->read_count += stored;
+
+ LOG(log_maxdebug, logtype_dsi, "dsi_stream_read(%u bytes): got: %u", length, stored);
return stored;
}
{
size_t len;
size_t buflen;
+
+ LOG(log_maxdebug, logtype_dsi, "dsi_buffered_stream_read: %u bytes", length);
- dsi_init_buffer(dsi);
len = from_buf(dsi, data, length); /* read from buffer dsi->buffer */
dsi->read_count += len;
if (len == length) { /* got enough bytes from there ? */
return len;
}
-/* ---------------------------------------
-*/
-void dsi_sleep(DSI *dsi, const int state)
-{
- dsi->asleep = state;
-}
-
/* ---------------------------------------
*/
static void block_sig(DSI *dsi)
int dsi_stream_send(DSI *dsi, void *buf, size_t length)
{
char block[DSI_BLOCKSIZ];
-#ifdef USE_WRITEV
struct iovec iov[2];
size_t towrite;
ssize_t len;
-#endif /* USE_WRITEV */
+
+ LOG(log_maxdebug, logtype_dsi, "dsi_stream_send: %u bytes",
+ length ? length : sizeof(block));
block[0] = dsi->header.dsi_flags;
block[1] = dsi->header.dsi_command;
/* block signals */
block_sig(dsi);
-#ifdef USE_WRITEV
iov[0].iov_base = block;
iov[0].iov_len = sizeof(block);
iov[1].iov_base = buf;
towrite = sizeof(block) + length;
dsi->write_count += towrite;
while (towrite > 0) {
- if (((len = writev(dsi->socket, iov, 2)) == -1 && errno == EINTR) ||
- !len)
- continue;
+ if (((len = writev(dsi->socket, iov, 2)) == -1 && errno == EINTR) || (len == 0))
+ continue;
- if ((size_t)len == towrite) /* wrote everything out */
- break;
- else if (len < 0) { /* error */
- if (errno == EAGAIN || errno == EWOULDBLOCK) {
- if (!dsi_buffer(dsi)) {
- continue;
+ if ((size_t)len == towrite) /* wrote everything out */
+ break;
+ else if (len < 0) { /* error */
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ if (!dsi_peek(dsi)) {
+ continue;
+ }
}
+ LOG(log_error, logtype_dsi, "dsi_stream_send: %s", strerror(errno));
+ unblock_sig(dsi);
+ return 0;
}
- LOG(log_error, logtype_dsi, "dsi_stream_send: %s", strerror(errno));
- unblock_sig(dsi);
- return 0;
- }
- towrite -= len;
- if (towrite > length) { /* skip part of header */
- iov[0].iov_base = (char *) iov[0].iov_base + len;
- iov[0].iov_len -= len;
- } else { /* skip to data */
- if (iov[0].iov_len) {
- len -= iov[0].iov_len;
- iov[0].iov_len = 0;
+ towrite -= len;
+ if (towrite > length) { /* skip part of header */
+ iov[0].iov_base = (char *) iov[0].iov_base + len;
+ iov[0].iov_len -= len;
+ } else { /* skip to data */
+ if (iov[0].iov_len) {
+ len -= iov[0].iov_len;
+ iov[0].iov_len = 0;
+ }
+ iov[1].iov_base = (char *) iov[1].iov_base + len;
+ iov[1].iov_len -= len;
}
- iov[1].iov_base = (char *) iov[1].iov_base + len;
- iov[1].iov_len -= len;
- }
}
-#else /* USE_WRITEV */
- /* write the header then data */
- if ((dsi_stream_write(dsi, block, sizeof(block), 1) != sizeof(block)) ||
- (dsi_stream_write(dsi, buf, length, 0) != length)) {
- unblock_sig(dsi);
- return 0;
- }
-#endif /* USE_WRITEV */
-
unblock_sig(dsi);
return 1;
}
{
char block[DSI_BLOCKSIZ];
+ LOG(log_maxdebug, logtype_dsi, "dsi_stream_receive: %u bytes", ilength);
+
/* read in the header */
if (dsi_buffered_stream_read(dsi, (u_int8_t *)block, sizeof(block)) != sizeof(block))
return 0;