MINOR: channel: Add functions to get info on buffers and deal with HTX streams

This patch adds HXT-aware versions of the functions c_data(), ci_data() and
c_empty(). channel_data() function returns the amount of data in the
channel, channel_input_data() returns the amount of input data and
channel_empty() returns true if the channel's buffer is empty. These
functions handles HTX buffers.

In addition, channel_data_limit() function, still HTX-aware, can be used to
get the maximum absolute amount of data that can be copied in a buffer,
independently on data already present in the buffer.

diff --git a/include/haproxy/channel.h b/include/haproxy/channel.h
index 8d299a6210532ff65611a2f97f10a41897bddd56..c6b3fae328c3e9fa7ff158dd26623725281c3cfc 100644 (file)
--- a/include/haproxy/channel.h
+++ b/include/haproxy/channel.h
@@ -782,6 +782,43 @@ static inline int channel_recv_max(const struct channel *chn)
        return ret;
 }
 
+/* Returns the maximum absolute amount of data that can be copied in a channel,
+ * taking the reserved space into account but also the HTX overhead for HTX
+ * streams.
+ */
+static inline size_t channel_data_limit(const struct channel *chn)
+{
+       size_t max = (global.tune.bufsize - global.tune.maxrewrite);
+
+       if (IS_HTX_STRM(chn_strm(chn)))
+               max -= HTX_BUF_OVERHEAD;
+       return max;
+}
+
+/* Returns the amount of data in a channel, taking the HTX streams into
+ * account. For raw channels, it is equivalent to c_data. For HTX channels, we
+ * rely on the HTX api.
+ */
+static inline size_t channel_data(const struct channel *chn)
+{
+       return (IS_HTX_STRM(chn_strm(chn)) ? htx_used_space(htxbuf(&chn->buf)) : c_data(chn));
+}
+
+/* Returns the amount of input data in a channel, taking he HTX streams into
+ * account. This function relies on channel_data().
+ */
+static inline size_t channel_input_data(const struct channel *chn)
+{
+       return channel_data(chn) - co_data(chn);
+}
+
+/* Returns 1 if the channel is empty, taking he HTX streams into account */
+static inline size_t channel_empty(const struct channel *chn)
+{
+       return (IS_HTX_STRM(chn) ? htx_is_empty(htxbuf(&chn->buf)) : c_empty(chn));
+}
+
+
 /* Returns the amount of bytes that can be written over the input data at once,
  * including reserved space which may be overwritten. This is used by Lua to
  * insert data in the input side just before the other data using buffer_replace().