spindly_outdata: use a list of outgoing nodes

Now all functions that generate binary outgoing SPDY protocol data will
fetch a node from the phys->pendq list to generate the binary in and
then add that node last in the phys->outq list. spindly_phys_outgoing()
then returns data from outq and puts the node back in phys->pendq.

src/spindly_phys.c

@@ -43,6 +43,7 @@ struct spindly_phys *spindly_phys_init(spindly_side_t side,
 {
   struct spindly_phys *phys;
   int rc;
+  struct spindly_outdata *od;
 
   /* this is the first malloc, it should use the malloc function provided in
      the config struct if set, but probably cannot use the MALLOC macro */
@@ -67,6 +68,16 @@ struct spindly_phys *spindly_phys_init(spindly_side_t side,
   _spindly_list_init(&phys->streams);
   _spindly_list_init(&phys->outq);
   _spindly_list_init(&phys->inq);
+  _spindly_list_init(&phys->pendq);
+
+  /* now add all outdata nodes to the pending queue */
+  for(rc=0; rc < PHYS_NUM_OUTDATA; rc++) {
+    od = CALLOC(phys, sizeof(struct spindly_outdata));
+    if(!od)
+      goto fail;
+
+    _spindly_list_add(&phys->pendq, &od->node);
+  }
 
   /* init receiver variables  */
   spdy_frame_init(&phys->frame);
@@ -81,6 +92,8 @@ struct spindly_phys *spindly_phys_init(spindly_side_t side,
   spdy_zlib_inflate_end(&phys->zlib_in);
   spdy_zlib_inflate_end(&phys->zlib_out);
 
+  /* TODO: clean up the pendq list */
+
   if(phys)
     free(phys);
 
@@ -104,21 +117,14 @@ spindly_error_t spindly_phys_outgoing(struct spindly_phys *phys,
                                       unsigned char **data,
                                       size_t *len)
 {
-  struct list_node *n = _spindly_list_first(&phys->outq);
-  if(n) {
-    struct spindly_stream *s= (struct spindly_stream *)
-      ((char *)n - offsetof(struct spindly_stream, outnode));
-
-    /* iterate over the attached streams and return binary data */
-    switch(s->out) {
-    case SPDY_CTRL_SYN_STREAM:
-    case SPDY_CTRL_SYN_REPLY:
-      *data = s->buffer;
-      *len = s->outlen;
-      /* remove this node from the outgoing queue */
-      _spindly_list_remove(&s->outnode);
-      break;
-    }
+  struct spindly_outdata *od = _spindly_list_first(&phys->outq);
+  if(od) {
+    *data = od->buffer;
+    *len = od->len;
+    /* remove this node from the outgoing queue */
+    _spindly_list_remove(&od->node);
+    /* add this node back to the pending queue */
+    _spindly_list_add(&phys->pendq, &od->node);
   }
   else {
     *data = NULL;

src/spindly_phys.h

@@ -26,6 +26,23 @@
 
 #include "spdy_frame.h"
 
+/*
+ * We use a set of pre-allocated structs in a linked list to put data in to
+ * get sent.
+ */
+#define PHYS_NUM_OUTDATA 64 /* number of allocated structs by default */
+#define PHYS_OUTBUFSIZE 128 /* size of buffer that avoids malloc */
+
+struct spindly_outdata {
+  struct list_node node;
+  size_t len; /* number of bytes of data provided */
+  unsigned char *alloced; /* if not NULL, an allocated pointer with data
+                             instead of buffer */
+  unsigned char buffer[PHYS_OUTBUFSIZE];
+  struct spindly_stream *stream; /* originating stream */
+};
+
+
 struct spindly_indata {
   struct list_node node;
   void *identifier;
@@ -50,6 +67,9 @@ struct spindly_phys
   struct list_head inq;
   size_t inq_size; /* total number of bytes in the queue */
 
+  /* list of spindly_outdata nodes that are unused */
+  struct list_head pendq;
+
   /* state variables for the parsing and demuxing of single incoming data
      stream */
   spdy_frame frame;

src/spindly_stream.c

@@ -71,9 +71,7 @@ spindly_error_t _spindly_stream_init(struct spindly_phys *phys,
   if(!madebypeer) {
     /* only send a SYN_STREAM if this stream is not the result of a received
        SYN_STREAM from the peer */
-
-    /* mark the current action */
-    s->out = SPDY_CTRL_SYN_STREAM;
+    struct spindly_outdata *od;
 
     /* make it a SYN_STREAM frame.
 
@@ -95,14 +93,20 @@ spindly_error_t _spindly_stream_init(struct spindly_phys *phys,
     if(rc)
       goto fail;
 
+    /* get an out buffer, TODO: what if drained? */
+    od = _spindly_list_first(&phys->pendq);
+
     /* pack a control frame to the output buffer */
-    rc = spdy_control_frame_pack(s->buffer, sizeof(s->buffer),
-                                 &s->outlen, &ctrl_frame);
+    rc = spdy_control_frame_pack(od->buffer, PHYS_OUTBUFSIZE,
+                                 &od->len, &ctrl_frame);
+
     if(rc)
       goto fail;
 
+    od->stream = s;
+
     /* add this handle to the outq */
-    _spindly_list_add(&phys->outq, &s->outnode);
+    _spindly_list_add(&phys->outq, &od->node);
   }
 
   /* append this stream to the list of streams held by the phys handle */
@@ -154,14 +158,11 @@ static spindly_error_t stream_acknack(struct spindly_stream *s, bool ack)
 {
   spindly_error_t rc = SPINDLYE_OK;
   spdy_control_frame ctrl_frame;
+  struct spindly_outdata *od;
 
   assert(s != NULL);
 
   /* queue up a SYN_REPLY or RST_STREAM message */
-
-  /* mark the current action */
-  s->out = ack?SPDY_CTRL_SYN_REPLY:SPDY_CTRL_RST_STREAM;
-
   if(ack)
     rc = spdy_control_mk_syn_reply(&ctrl_frame, s->streamid, NULL);
   else
@@ -170,14 +171,19 @@ static spindly_error_t stream_acknack(struct spindly_stream *s, bool ack)
   if(rc)
     goto fail;
 
+  /* get an out buffer TODO: what if drained? */
+  od = _spindly_list_first(&s->phys->pendq);
+
   /* pack a control frame to the output buffer */
-  rc = spdy_control_frame_pack(s->buffer, sizeof(s->buffer),
-                               &s->outlen, &ctrl_frame);
+  rc = spdy_control_frame_pack(od->buffer, PHYS_OUTBUFSIZE,
+                               &od->len, &ctrl_frame);
   if(rc)
     goto fail;
 
+  od->stream = s;
+
   /* add this handle to the outq */
-  _spindly_list_add(&s->phys->outq, &s->outnode);
+  _spindly_list_add(&s->phys->outq, &od->node);
 
   fail:
   return rc;

src/spindly_stream.h

@@ -23,8 +23,6 @@
 #include "spdy_zlib.h"
 #include "spdy_stream.h"
 
-#define STREAM_BUFSIZE 32 /* scratch buffer for generated frame contents */
-
 enum stream_state
 {
   STREAM_NEW,                   /* as before the peer has ACKed it */
@@ -44,17 +42,9 @@ struct spindly_stream
   void *userp;                  /* set in stream_new() */
   unsigned int prio;            /* 0 - 7 */
 
-  int out; /* when this handle is added to the outq, this field will hold the
-              hint of what to send */
-  size_t outlen; /* number of bytes in 'buffer' that is stored and ready to
-                    get sent off */
-  struct list_node outnode;
-
   struct spindly_stream_config *config;
 
   spdy_stream spdy;
-
-  unsigned char buffer[STREAM_BUFSIZE];
 };
 
 #define PRIO_MAX 7