/*
This file is part of GNUnet.
- (C) 2009 Christian Grothoff (and other contributing authors)
+ (C) 2010 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
#include "gnunet_server_lib.h"
#include "gnunet_time_lib.h"
+#define DEBUG_SERVER_MST GNUNET_EXTRA_LOGGING
+
+#if HAVE_UNALIGNED_64_ACCESS
+#define ALIGN_FACTOR 4
+#else
+#define ALIGN_FACTOR 8
+#endif
+
+#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
+
/**
* Handle to a message stream tokenizer.
struct GNUNET_SERVER_MessageStreamTokenizer
{
- size_t maxbuf;
+ /**
+ * Function to call on completed messages.
+ */
+ GNUNET_SERVER_MessageTokenizerCallback cb;
- size_t off;
+ /**
+ * Closure for cb.
+ */
+ void *cb_cls;
- void *client_identity;
+ /**
+ * Size of the buffer (starting at 'hdr').
+ */
+ size_t curr_buf;
- GNUNET_SERVER_MessageTokenizerCallback cb;
+ /**
+ * How many bytes in buffer have we already processed?
+ */
+ size_t off;
- void *cb_cls;
+ /**
+ * How many bytes in buffer are valid right now?
+ */
+ size_t pos;
/**
- * Beginning of the buffer.
+ * Beginning of the buffer. Typed like this to force alignment.
*/
- struct GNUNET_MessageHeader hdr;
+ struct GNUNET_MessageHeader *hdr;
};
/**
* Create a message stream tokenizer.
*
- * @param maxbuf maximum message size to support (typically
- * GNUNET_SERVER_MAX_MESSAGE_SIZE)
- * @param client_identity ID of client for which this is a buffer,
- * can be NULL (will be passed back to 'cb')
+ * @param cb function to call on completed messages
+ * @param cb_cls closure for cb
* @return handle to tokenizer
*/
struct GNUNET_SERVER_MessageStreamTokenizer *
-GNUNET_SERVER_mst_create (size_t maxbuf,
- void *client_identity,
- GNUNET_SERVER_MessageTokenizerCallback cb,
- void *cb_cls)
+GNUNET_SERVER_mst_create (GNUNET_SERVER_MessageTokenizerCallback cb,
+ void *cb_cls)
{
struct GNUNET_SERVER_MessageStreamTokenizer *ret;
- ret = GNUNET_malloc (maxbuf + sizeof (struct GNUNET_SERVER_MessageStreamTokenizer));
- ret->maxbuf = maxbuf;
- ret->client_identity = client_identity;
+ ret = GNUNET_malloc (sizeof (struct GNUNET_SERVER_MessageStreamTokenizer));
+ ret->hdr = GNUNET_malloc (GNUNET_SERVER_MIN_BUFFER_SIZE);
+ ret->curr_buf = GNUNET_SERVER_MIN_BUFFER_SIZE;
ret->cb = cb;
ret->cb_cls = cb_cls;
return ret;
* callback for all complete messages.
*
* @param mst tokenizer to use
+ * @param client_identity ID of client for which this is a buffer
* @param buf input data to add
* @param size number of bytes in buf
- * @param purge should any excess bytes in the buffer be discarded
+ * @param purge should any excess bytes in the buffer be discarded
* (i.e. for packet-based services like UDP)
* @param one_shot only call callback once, keep rest of message in buffer
* @return GNUNET_OK if we are done processing (need more data)
*/
int
GNUNET_SERVER_mst_receive (struct GNUNET_SERVER_MessageStreamTokenizer *mst,
- const char *buf,
- size_t size,
- int purge,
- int one_shot)
+ void *client_identity, const char *buf, size_t size,
+ int purge, int one_shot)
{
const struct GNUNET_MessageHeader *hdr;
size_t delta;
- size_t want;
+ uint16_t want;
char *ibuf;
int need_align;
unsigned long offset;
int ret;
+ GNUNET_assert (mst->off <= mst->pos);
+ GNUNET_assert (mst->pos <= mst->curr_buf);
+#if DEBUG_SERVER_MST
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Server-mst receives %u bytes with %u bytes already in private buffer\n",
+ (unsigned int) size, (unsigned int) (mst->pos - mst->off));
+#endif
ret = GNUNET_OK;
- ibuf = (char*) &mst->hdr;
- if (mst->off > 0)
+ ibuf = (char *) mst->hdr;
+ while (mst->pos > 0)
+ {
+do_align:
+ GNUNET_assert (mst->pos >= mst->off);
+ if ((mst->curr_buf - mst->off < sizeof (struct GNUNET_MessageHeader)) ||
+ (0 != (mst->off % ALIGN_FACTOR)))
+ {
+ /* need to align or need more space */
+ mst->pos -= mst->off;
+ memmove (ibuf, &ibuf[mst->off], mst->pos);
+ mst->off = 0;
+ }
+ if (mst->pos - mst->off < sizeof (struct GNUNET_MessageHeader))
+ {
+ delta =
+ GNUNET_MIN (sizeof (struct GNUNET_MessageHeader) -
+ (mst->pos - mst->off), size);
+ memcpy (&ibuf[mst->pos], buf, delta);
+ mst->pos += delta;
+ buf += delta;
+ size -= delta;
+ }
+ if (mst->pos - mst->off < sizeof (struct GNUNET_MessageHeader))
+ {
+ if (purge)
+ {
+ mst->off = 0;
+ mst->pos = 0;
+ }
+ return GNUNET_OK;
+ }
+ hdr = (const struct GNUNET_MessageHeader *) &ibuf[mst->off];
+ want = ntohs (hdr->size);
+ if (want < sizeof (struct GNUNET_MessageHeader))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
+ }
+ if ( (mst->curr_buf - mst->off < want) &&
+ (mst->off > 0) )
+ {
+ /* can get more space by moving */
+ mst->pos -= mst->off;
+ memmove (ibuf, &ibuf[mst->off], mst->pos);
+ mst->off = 0;
+ }
+ if (mst->curr_buf < want)
+ {
+ /* need to get more space by growing buffer */
+ GNUNET_assert (0 == mst->off);
+ mst->hdr = GNUNET_realloc (mst->hdr, want);
+ ibuf = (char *) mst->hdr;
+ mst->curr_buf = want;
+ }
+ hdr = (const struct GNUNET_MessageHeader *) &ibuf[mst->off];
+ if (mst->pos - mst->off < want)
+ {
+ delta = GNUNET_MIN (want - (mst->pos - mst->off), size);
+ GNUNET_assert (mst->pos + delta <= mst->curr_buf);
+ memcpy (&ibuf[mst->pos], buf, delta);
+ mst->pos += delta;
+ buf += delta;
+ size -= delta;
+ }
+ if (mst->pos - mst->off < want)
+ {
+ if (purge)
+ {
+ mst->off = 0;
+ mst->pos = 0;
+ }
+ return GNUNET_OK;
+ }
+ if (one_shot == GNUNET_SYSERR)
{
- do_align:
- if (mst->off < sizeof (struct GNUNET_MessageHeader))
- {
- delta = GNUNET_MIN (sizeof (struct GNUNET_MessageHeader) - mst->off,
- size);
- memcpy (&ibuf[mst->off],
- buf,
- delta);
- mst->off += delta;
- buf += delta;
- size -= delta;
- }
- if (mst->off < sizeof (struct GNUNET_MessageHeader))
- {
- if (purge)
- mst->off = 0;
- return GNUNET_OK;
- }
- want = ntohs (mst->hdr.size);
+ /* cannot call callback again, but return value saying that
+ * we have another full message in the buffer */
+ ret = GNUNET_NO;
+ goto copy;
+ }
+ if (one_shot == GNUNET_YES)
+ one_shot = GNUNET_SYSERR;
+ mst->off += want;
+ mst->cb (mst->cb_cls, client_identity, hdr);
+ if (mst->off == mst->pos)
+ {
+ /* reset to beginning of buffer, it's free right now! */
+ mst->off = 0;
+ mst->pos = 0;
+ }
+ }
+ GNUNET_assert (0 == mst->pos);
+ while (size > 0)
+ {
+#if DEBUG_SERVER_MST
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Server-mst has %u bytes left in inbound buffer\n",
+ (unsigned int) size);
+#endif
+ if (size < sizeof (struct GNUNET_MessageHeader))
+ break;
+ offset = (unsigned long) buf;
+ need_align = (0 != (offset % ALIGN_FACTOR)) ? GNUNET_YES : GNUNET_NO;
+ if (GNUNET_NO == need_align)
+ {
+ /* can try to do zero-copy and process directly from original buffer */
+ hdr = (const struct GNUNET_MessageHeader *) buf;
+ want = ntohs (hdr->size);
if (want < sizeof (struct GNUNET_MessageHeader))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if (want < mst->off)
- {
- delta = GNUNET_MIN (want - mst->off,
- size);
- memcpy (&ibuf[mst->off],
- buf,
- delta);
- mst->off += delta;
- buf += delta;
- size -= delta;
- }
- if (want < mst->off)
- {
- if (purge)
- mst->off = 0;
- return GNUNET_OK;
- }
+ {
+ GNUNET_break_op (0);
+ mst->off = 0;
+ return GNUNET_SYSERR;
+ }
+ if (size < want)
+ break; /* or not: buffer incomplete, so copy to private buffer... */
if (one_shot == GNUNET_SYSERR)
- {
- ret = GNUNET_NO;
- goto copy;
- }
+ {
+ /* cannot call callback again, but return value saying that
+ * we have another full message in the buffer */
+ ret = GNUNET_NO;
+ goto copy;
+ }
if (one_shot == GNUNET_YES)
- one_shot = GNUNET_SYSERR;
- mst->cb (mst->cb_cls, mst->client_identity, &mst->hdr);
- mst->off = 0;
+ one_shot = GNUNET_SYSERR;
+ mst->cb (mst->cb_cls, client_identity, hdr);
+ buf += want;
+ size -= want;
}
- while (size > 0)
+ else
{
- if (size < sizeof (struct GNUNET_MessageHeader))
- break;
- offset = (unsigned long) buf;
-#if HAVE_UNALIGNED_64_ACCESS
- need_align = (0 != offset % 4) ? GNUNET_YES : GNUNET_NO;
-#else
- need_align = (0 != offset % 8) ? GNUNET_YES : GNUNET_NO;
-#endif
- if (GNUNET_NO == need_align)
- {
- /* can try to do zero-copy */
- hdr = (const struct GNUNET_MessageHeader *) buf;
- want = ntohs (hdr->size);
- if (size < want)
- break; /* or not, buffer incomplete... */
- if (one_shot == GNUNET_SYSERR)
- {
- ret = GNUNET_NO;
- goto copy;
- }
- if (one_shot == GNUNET_YES)
- one_shot = GNUNET_SYSERR;
- mst->cb (mst->cb_cls, mst->client_identity, hdr);
- buf += want;
- size -= want;
- }
- else
- {
- /* yes, we go a bit more spagetti than usual here */
- goto do_align;
- }
+ /* need to copy to private buffer to align;
+ * yes, we go a bit more spagetti than usual here */
+ goto do_align;
}
- copy:
- if ( (size > 0) && (! purge) )
+ }
+copy:
+ if ((size > 0) && (!purge))
+ {
+ if (size + mst->pos > mst->curr_buf)
{
- memcpy (&ibuf[mst->off], buf, size);
- mst->off += size;
- size = 0;
+ mst->hdr = GNUNET_realloc (mst->hdr, size + mst->pos);
+ ibuf = (char *) mst->hdr;
+ mst->curr_buf = size + mst->pos;
}
+ GNUNET_assert (size + mst->pos <= mst->curr_buf);
+ memcpy (&ibuf[mst->pos], buf, size);
+ mst->pos += size;
+ }
if (purge)
- mst->off = 0;
+ {
+ mst->off = 0;
+ mst->pos = 0;
+ }
+#if DEBUG_SERVER_MST
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Server-mst leaves %u bytes in private buffer\n",
+ (unsigned int) (mst->pos - mst->off));
+#endif
return ret;
}
void
GNUNET_SERVER_mst_destroy (struct GNUNET_SERVER_MessageStreamTokenizer *mst)
{
+ GNUNET_free (mst->hdr);
GNUNET_free (mst);
}