istream-seekable: Minor code cleanup.

diff --git a/src/lib/istream-seekable.c b/src/lib/istream-seekable.c
index f18248816169961684bb23d2d7bfb9f24696b2dc..8143e6e8cced62ece5435be1ca5294764f3561ce 100644 (file)
--- a/src/lib/istream-seekable.c
+++ b/src/lib/istream-seekable.c
@@ -157,8 +157,9 @@ static bool read_from_buffer(struct seekable_istream *sstream, ssize_t *ret_r)
        const unsigned char *data;
        size_t size, pos, offset;
 
-       if (stream->istream.v_offset +
-           (stream->pos - stream->skip) >= sstream->buffer->used) {
+       i_assert(stream->skip == 0);
+
+       if (stream->istream.v_offset + stream->pos >= sstream->buffer->used) {
                /* need to read more */
                if (sstream->buffer->used >= stream->max_buffer_size)
                        return FALSE;
@@ -176,6 +177,7 @@ static bool read_from_buffer(struct seekable_istream *sstream, ssize_t *ret_r)
 
                /* we should have more now. */
                data = i_stream_get_data(sstream->cur_input, &size);
+               i_assert(size > 0);
                buffer_append(sstream->buffer, data, size);
                i_stream_skip(sstream->cur_input, size);
        }