Make sure stream->offset points to the position in stream corresponding to the start of the buffer.

* libmailutils/stream/stream.c (_stream_fill_buffer): Keep track of the current offset. (mu_stream_seek): avoid unnecessary seeks. (_stream_skip_input_bytes): Call _stream_flush_buffer before _stream_fill_buffer. (_stream_write_unbuffered): Do not modify current offset. (mu_stream_read,mu_stream_write): For unbuffered streams, modify current offset after invoking the corresponding I/O call. (_stream_scandelim): Call _stream_flush_buffer before _stream_fill_buffer.

Make sure stream->offset points to the position in stream corresponding to the start of the buffer.
* libmailutils/stream/stream.c (_stream_fill_buffer): Keep track of the current offset. (mu_stream_seek): avoid unnecessary seeks. (_stream_skip_input_bytes): Call _stream_flush_buffer before _stream_fill_buffer. (_stream_write_unbuffered): Do not modify current offset. (mu_stream_read,mu_stream_write): For unbuffered streams, modify current offset after invoking the corresponding I/O call. (_stream_scandelim): Call _stream_flush_buffer before _stream_fill_buffer.
Sergey Poznyakoff
Commit 96cfdb5e ... 96cfdb5e8ef877b1f8773e426061ef4d3442997e authored 2010-11-09 12:41:22 +0200 by Sergey Poznyakoff
Showing 1 changed file with 46 additions and 17 deletions
libmailutils/stream/stream.c
--- a/libmailutils/stream/stream.c
View file @96cfdb5
+++ b/libmailutils/stream/stream.c
View file @96cfdb5
@@ -110,7 +110,6 @@ _stream_fill_buffer (struct _mu_stream *stream)
  int rc = 0;
  char c;
-  stream->offset += stream->level;
  switch (stream->buftype)
    {
    case mu_buffer_none:
@@ -127,7 +126,8 @@ _stream_fill_buffer (struct _mu_stream *stream)
      for (n = 0;
 	   n < stream->bufsize
 	     && (rc = _stream_read_unbuffered (stream,
-					       &c, 1, 0, &rdn)) == 0;)
+					       &c, 1,
+					       0, &rdn)) == 0;)
 	{
 	  if (rdn == 0)
 	    {
@@ -143,7 +143,6 @@ _stream_fill_buffer (struct _mu_stream *stream)
    }
  if (rc == 0)
    {
-      stream->offset -= stream->level;
      stream->pos = 0;
      _stream_event (stream, _MU_STR_EVENT_FILLBUF,
 		     stream->level, _stream_curp (stream));
@@ -193,7 +192,8 @@ _stream_flush_buffer (struct _mu_stream *stream, int flags)
 	case mu_buffer_full:
 	  if ((rc = _stream_write_unbuffered (stream, stream->buffer,
-					      stream->level, 1, NULL)))
+					      stream->level,
+					      1, NULL)))
 	    return rc;
 	  _stream_event (stream, _MU_STR_EVENT_FLUSHBUF,
 			 stream->level, stream->buffer);
@@ -208,7 +208,8 @@ _stream_flush_buffer (struct _mu_stream *stream, int flags)
 	       end = memchr (start, '\n', wrsize))
 	    {
 	      size_t size = end - start + 1;
-	      rc = _stream_write_unbuffered (stream, start, size, 1, NULL);
+	      rc = _stream_write_unbuffered (stream, start, size,
+					     1, NULL);
 	      if (rc)
 		return rc;
 	      _stream_event (stream, _MU_STR_EVENT_FLUSHBUF,
@@ -231,18 +232,26 @@ _stream_flush_buffer (struct _mu_stream *stream, int flags)
 			     wrsize, stream->buffer);
 	      wrsize = 0;
 	    }
+	  if (!(flags & _MU_STR_FLUSH_KEEP))
+	    {
 	      if (wrsize)
 		memmove (stream->buffer, start, wrsize);
 	      else
 		_stream_clrflag (stream, _MU_STR_DIRTY);
+	      stream->offset += stream->level - wrsize;
 	      stream->level = stream->pos = wrsize;
 	      return 0;
 	    }
+	}
      _stream_clrflag (stream, _MU_STR_DIRTY);
    }
  if (!(flags & _MU_STR_FLUSH_KEEP))
+    {
+      stream->offset += stream->level;
      stream->pos = stream->level = 0;
+    }
  return 0;
 }
@@ -413,19 +422,21 @@ mu_stream_seek (mu_stream_t stream, mu_off_t offset, int whence,
      return mu_stream_seterr (stream, EINVAL, 1);
    }
-  if (stream->buftype == mu_buffer_none ?
+  if (!(stream->buftype == mu_buffer_none ?
-      (offset != stream->offset)
+	(offset == stream->offset)
-       : (stream->level == 0
+	: (stream->offset <= offset &&
-	  || offset < stream->offset
+	   offset < stream->offset + stream->level)))
-	  || offset > stream->offset + stream->level))
    {
      if ((rc = _stream_flush_buffer (stream, _MU_STR_FLUSH_ALL)))
 	return rc;
+      if (stream->offset != offset)
+	{
 	  rc = stream->seek (stream, offset, &stream->offset);
 	  if (rc == ESPIPE)
 	    return rc;
 	  if (rc)
 	    return mu_stream_seterr (stream, rc, 1);
+	}
      _mu_stream_cleareof (stream);
    }
  else if (stream->buftype != mu_buffer_none)
@@ -476,10 +487,10 @@ _stream_skip_input_bytes (mu_stream_t stream, mu_off_t count, mu_off_t *pres)
 	{
 	  for (pos = 0;;)
 	    {
-	      if ((rc = _stream_flush_buffer (stream, _MU_STR_FLUSH_ALL)))
-		return rc;
 	      if (stream->pos == stream->level)
 		{
+		  if ((rc = _stream_flush_buffer (stream, _MU_STR_FLUSH_ALL)))
+		    return rc;
 		  rc = _stream_fill_buffer (stream);
 		  if (rc)
 		    break;
@@ -602,7 +613,6 @@ _stream_read_unbuffered (mu_stream_t stream, void *buf, size_t size,
 	  nread += rdbytes;
 	  size -= rdbytes;
 	  stream->bytes_in += rdbytes;
 	}
      if (size && rc)
 	rc = mu_stream_seterr (stream, rc, 0);
@@ -618,7 +628,6 @@ _stream_read_unbuffered (mu_stream_t stream, void *buf, size_t size,
 	}
      mu_stream_seterr (stream, rc, rc != 0);
    }
-    stream->offset += nread;
  if (pnread)
    *pnread = nread;
@@ -677,7 +686,6 @@ _stream_write_unbuffered (mu_stream_t stream,
 	stream->bytes_out += nwritten;
    }
  _stream_setflag (stream, _MU_STR_WRT);
-  stream->offset += nwritten;
  if (pnwritten)
    *pnwritten = nwritten;
  mu_stream_seterr (stream, rc, rc != 0);
@@ -695,7 +703,14 @@ mu_stream_read (mu_stream_t stream, void *buf, size_t size, size_t *pread)
    }
  if (stream->buftype == mu_buffer_none)
-    return _stream_read_unbuffered (stream, buf, size, !pread, pread);
+    {
+      size_t nread = 0;
+      int rc = _stream_read_unbuffered (stream, buf, size, !pread, &nread);
+      stream->offset += nread;
+      if (pread)
+	*pread = nread;
+      return rc;
+    }
  else
    {
      char *bufp = buf;
@@ -712,6 +727,12 @@ mu_stream_read (mu_stream_t stream, void *buf, size_t size, size_t *pread)
 	  if (stream->pos == stream->level)
 	    {
+	      if ((rc = _stream_flush_buffer (stream, _MU_STR_FLUSH_ALL)))
+		{
+		  if (nbytes)
+		    break;
+		  return rc;
+		}
 	      if ((rc = _stream_fill_buffer (stream)))
 		{
 		  if (nbytes)
@@ -757,6 +778,8 @@ _stream_scandelim (mu_stream_t stream, char *buf, size_t size, int delim,
      if (stream->pos == stream->level)
 	{
+	  if ((rc = _stream_flush_buffer (stream, _MU_STR_FLUSH_ALL)))
+	    break;
 	  if ((rc = _stream_fill_buffer (stream)) || stream->level == 0)
 	    break;
 	}
@@ -959,8 +982,14 @@ mu_stream_write (mu_stream_t stream, const void *buf, size_t size,
    }
  if (stream->buftype == mu_buffer_none)
+    {
+      size_t nwritten;
      rc = _stream_write_unbuffered (stream, buf, size,
-				   !pnwritten, pnwritten);
+				     !pnwritten, &nwritten);
+      stream->offset += nwritten;
+      if (pnwritten)
+	*pnwritten = nwritten;
+    }
  else
    {
      size_t nbytes = 0;