ubxcore: introduce block attributes ACTIVE and TRIGGER

the first block attributes describe whether a block is a trigger
or/and whether it is active (i.e. spawns a thread internally like
ptrig or webif). This information is useful in different circumstances
such as for determining startup and shutdown order by ubx_launch.

Suggested-by: Enea Scioni <enea.scioni@kuleuven.be>
Signed-off-by: Markus Klotzbuecher <mk@mkio.de>

API_Changes.md

@@ -5,6 +5,12 @@ This file tracks user visible API changes.
 
 ## Unreleased
 
+- struct ubx_block: added attributes variable (`attrs`) and defined
+  first block attributes (`BLOCK_ATTR_TRIGGER` and
+  `BLOCK_ATTR_ACTIVE`). These will be used by tools such as
+  ubx_launch, so blocks should be updated to define these
+  appropriately.
+
 - blockdiagram.load: change to return `system` or fail and exit
 
 - rtlog: enable gcc format checking. This checks the provided

libubx/ubx.c

@@ -927,6 +927,7 @@ static ubx_block_t* ubx_block_clone(ubx_block_t* prot, const char* name)
 
 	/* copy attributes of prototype */
 	newb->type = prot->type;
+	newb->attrs = prot->attrs;
 
 	if((newb->name=strdup(name))==NULL) goto out_free;
 	if((newb->meta_data=strdup(prot->meta_data))==NULL) goto out_free;

libubx/ubx_types.h

@@ -172,7 +172,7 @@ typedef struct ubx_config
 } ubx_config_t;
 
 enum {
-	CONFIG_ATTR_RDWR =	0<<0,
+	CONFIG_ATTR_RDWR =	0,
 	CONFIG_ATTR_RDONLY =	1<<0
 };
 
@@ -186,6 +186,13 @@ enum {
 	BLOCK_TYPE_INTERACTION
 };
 
+/* Block attributes */
+enum {
+	BLOCK_ATTR_TRIGGER = 	1<<0,	/* block is a trigger */
+	BLOCK_ATTR_ACTIVE = 	1<<1,	/* block is active (has a thread) */
+};
+
+/* block states */
 enum {
 	BLOCK_STATE_PREINIT,
 	BLOCK_STATE_INACTIVE,
@@ -198,6 +205,7 @@ typedef struct ubx_block
 	const char* name;	/* type name */
 	const char* meta_data;	/* doc, etc. */
 	uint32_t type;		/* type, (computation, interaction) */
+	uint32_t attrs;		/* attributes */
 
 	ubx_port_t* ports;
 	ubx_config_t* configs;

lua/ubx.lua.source

@@ -9,6 +9,7 @@
 --
 
 local ffi=require "ffi"
+local bit=require "bit"
 local cdata = require "cdata"
 local utils= require "utils"
 local ts=tostring
@@ -100,6 +101,11 @@ local function setup_enums()
       [ffi.C.BLOCK_STATE_INACTIVE]='inactive',
       [ffi.C.BLOCK_STATE_ACTIVE]='active'
    }
+
+   M.block_attrs_tostr={
+      [ffi.C.BLOCK_ATTR_TRIGGER]='trigger',
+      [ffi.C.BLOCK_ATTR_ACTIVE]='active',
+   }
 end
 
 -- load ubx_types and library
@@ -144,7 +150,7 @@ void *malloc(size_t size);
 void free(void *ptr);
 void *calloc(size_t nmemb, size_t size);
 void *realloc(void *ptr, size_t size);
- ]]
+]]
 
 local prefix=find_prefix()
 load_ubx_ffi(prefix)
@@ -477,6 +483,13 @@ local function block_state_color(sstr)
    end
 end
 
+local function block_attr_totab(b)
+   local t = {}
+   if bit.band(b.attrs, ffi.C.BLOCK_ATTR_TRIGGER) ~= 0 then t[#t+1] = "trigger" end
+   if bit.band(b.attrs, ffi.C.BLOCK_ATTR_ACTIVE) ~= 0 then t[#t+1] = "active" end
+   return t
+end
+
 --- Convert block to lua table
 -- @param b block to convert to table
 -- @return table
@@ -485,6 +498,7 @@ function M.block_totab(b)
 
    local res = {}
    res.name = M.safe_tostr(b.name)
+   res.attrs = block_attr_totab(b)
    res.meta_data = M.safe_tostr(b.meta_data)
    res.block_type=M.block_type_tostr[b.type]
    res.state = M.block_state_tostr[b.block_state]
@@ -517,11 +531,14 @@ function M.block_pp(b)
 
    if M.is_block(b) then bt = M.block_totab(b) else bt = b end
 
-   local fmt = "%s (type=%s, state=%s, prototype=%s)"
+   local fmt = "%s [state: %s, steps: %u] (type: %s, prototype: %s, attrs: %s)"
 
-   res[#res+1] = fmt:format(green(bt.name), bt.block_type,
+   res[#res+1] = fmt:format(green(bt.name),
 			    block_state_color(bt.state),
-			    blue(bt.prototype), bt.stat_num_steps)
+			    bt.stat_num_steps,
+			    bt.block_type,
+			    blue(bt.prototype),
+			    table.concat(bt.attrs, ', '))
 
    if #bt.ports > 0 then
       res[#res+1] = ("  ports:")
@@ -551,11 +568,12 @@ function M.block_tostr(b)
       return ("%s [%s]"):format(green(bt.name), bt.block_type)
    end
 
-   return ("%s [%s, %s, %s]"):format(
+   return ("%s [%s, %s, %s, attrs: %s]"):format(
       green(bt.name),
       bt.block_type,
       block_state_color(bt.state),
-      blue(bt.prototype))
+      blue(bt.prototype),
+      table.concat(bt.attrs, ', '))
 end
 
 function M.block_port_get (b, n)

std_blocks/ptrig/ptrig.c

@@ -502,6 +502,7 @@ static void ptrig_cleanup(ubx_block_t *b)
 ubx_block_t ptrig_comp = {
 	.name = "std_triggers/ptrig",
 	.type = BLOCK_TYPE_COMPUTATION,
+	.attrs = BLOCK_ATTR_TRIGGER | BLOCK_ATTR_ACTIVE,
 	.meta_data = ptrig_meta,
 
 	.configs = ptrig_config,

std_blocks/trig/trig.c

@@ -238,6 +238,7 @@ void trig_cleanup(ubx_block_t *b)
 ubx_block_t trig_comp = {
 	.name = "std_triggers/trig",
 	.type = BLOCK_TYPE_COMPUTATION,
+	.attrs = BLOCK_ATTR_TRIGGER,
 	.meta_data = trig_meta,
 	.configs = trig_config,
 	.ports = trig_ports,

std_blocks/webif/webif.c

@@ -226,6 +226,7 @@ static void wi_stop(ubx_block_t *c)
 ubx_block_t webif_comp = {
 	.name = "webif/webif",
 	.type = BLOCK_TYPE_COMPUTATION,
+	.attrs = BLOCK_ATTR_ACTIVE,
 	.meta_data = wi_meta,
 	.configs = webif_conf,