X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Futil%2Fserver_mst.c;h=0a686a079e6323e44ef949a774fd4c6ef991c21c;hb=60de5f48cbfc3868570284e91415ca7e06c390e1;hp=8df4e4b7d3af2faff255e8c4ec15716675bb899c;hpb=09082d4872f060aedf1364fb5ebc1584ee4c47d6;p=oweals%2Fgnunet.git

diff --git a/src/util/server_mst.c b/src/util/server_mst.c
index 8df4e4b7d..0a686a079 100644
--- a/src/util/server_mst.c
+++ b/src/util/server_mst.c
@@ -1,10 +1,10 @@
 /*
      This file is part of GNUnet.
-     (C) 2009 Christian Grothoff (and other contributing authors)
+     Copyright (C) 2010 GNUnet e.V.
 
      GNUnet is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published
-     by the Free Software Foundation; either version 2, or (at your
+     by the Free Software Foundation; either version 3, or (at your
      option) any later version.
 
      GNUnet is distributed in the hope that it will be useful, but
@@ -14,8 +14,8 @@
 
      You should have received a copy of the GNU General Public License
      along with GNUnet; see the file COPYING.  If not, write to the
-     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-     Boston, MA 02111-1307, USA.
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
 */
 
 /**
@@ -25,11 +25,16 @@
  */
 
 #include "platform.h"
-#include "gnunet_common.h"
-#include "gnunet_connection_lib.h"
-#include "gnunet_scheduler_lib.h"
-#include "gnunet_server_lib.h"
-#include "gnunet_time_lib.h"
+#include "gnunet_util_lib.h"
+
+
+#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__)
 
 
 /**
@@ -38,20 +43,35 @@
 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;
 
 };
 
@@ -60,23 +80,19 @@ struct GNUNET_SERVER_MessageStreamTokenizer
 /**
  * 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 @a 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_new (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;
@@ -88,128 +104,194 @@ GNUNET_SERVER_mst_create (size_t maxbuf,
  * 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 size number of bytes in @a buf
+ * @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)
- *         GNUNET_NO if one_shot was set and we have another message ready
- *         GNUNET_SYSERR if the data stream is corrupt
+ * @return #GNUNET_OK if we are done processing (need more data)
+ *         #GNUNET_NO if @a one_shot was set and we have another message ready
+ *         #GNUNET_SYSERR if the data stream is corrupt
  */
 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);
+  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));
   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))
     {
-    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);
+      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)
+    {
+      /* 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;
+    if (GNUNET_SYSERR == mst->cb (mst->cb_cls, client_identity, hdr))
+      return GNUNET_SYSERR;
+    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)
+  {
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Server-mst has %u bytes left in inbound buffer\n",
+         (unsigned int) size);
+    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;
+      if (GNUNET_SYSERR == mst->cb (mst->cb_cls, client_identity, hdr))
+        return GNUNET_SYSERR;
+      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;
+  }
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Server-mst leaves %u bytes in private buffer\n",
+       (unsigned int) (mst->pos - mst->off));
   return ret;
 }
 
@@ -222,6 +304,7 @@ GNUNET_SERVER_mst_receive (struct GNUNET_SERVER_MessageStreamTokenizer *mst,
 void
 GNUNET_SERVER_mst_destroy (struct GNUNET_SERVER_MessageStreamTokenizer *mst)
 {
+  GNUNET_free (mst->hdr);
   GNUNET_free (mst);
 }