session: make group of 'static' vars more visible

Put the collection of 'static' variables in datafeed_in() to the top of
the declaration block, to raise awareness during maintenance. These are
"semi global" variables with reduced visibility but extended lifetime.

Update a comment while I'm here. Explain what the early "header packet"
check does instead of what it doesn't.

diff --git a/session.c b/session.c
index 152f9790b818bcffc94a1e81b1796852abbe8ce4..c5eb7aad3988e2ad67f8aae3725c5024f8f419c1 100644 (file)
--- a/session.c
+++ b/session.c
@@ -153,11 +153,6 @@ const struct sr_transform *setup_transform_module(const struct sr_dev_inst *sdi)
 void datafeed_in(const struct sr_dev_inst *sdi,
                const struct sr_datafeed_packet *packet, void *cb_data)
 {
-       const struct sr_datafeed_meta *meta;
-       const struct sr_datafeed_logic *logic;
-       const struct sr_datafeed_analog *analog;
-       struct sr_session *session;
-       struct sr_config *src;
        static const struct sr_output *o = NULL;
        static const struct sr_output *oa = NULL;
        static uint64_t rcvd_samples_logic = 0;
@@ -165,6 +160,12 @@ void datafeed_in(const struct sr_dev_inst *sdi,
        static uint64_t samplerate = 0;
        static int triggered = 0;
        static FILE *outfile = NULL;
+
+       const struct sr_datafeed_meta *meta;
+       const struct sr_datafeed_logic *logic;
+       const struct sr_datafeed_analog *analog;
+       struct sr_session *session;
+       struct sr_config *src;
        GSList *l;
        GString *out;
        GVariant *gvar;
@@ -178,7 +179,7 @@ void datafeed_in(const struct sr_dev_inst *sdi,
 
        driver = sr_dev_inst_driver_get(sdi);
 
-       /* If the first packet to come in isn't a header, don't even try. */
+       /* Skip all packets before the first header. */
        if (packet->type != SR_DF_HEADER && !o)
                return;