GNU Radio Manual and C++ API Reference  3.10.1.1
The Free & Open Software Radio Ecosystem
basic_block.h
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1 /* -*- c++ -*- */
2 /*
3  * Copyright 2006,2008,2009,2011,2013 Free Software Foundation, Inc.
4  *
5  * This file is part of GNU Radio
6  *
7  * SPDX-License-Identifier: GPL-3.0-or-later
8  *
9  */
10 
11 #ifndef INCLUDED_GR_BASIC_BLOCK_H
12 #define INCLUDED_GR_BASIC_BLOCK_H
13 
14 #include <gnuradio/api.h>
15 #include <gnuradio/io_signature.h>
16 #include <gnuradio/logger.h>
17 #include <gnuradio/msg_accepter.h>
18 #include <gnuradio/runtime_types.h>
19 #include <gnuradio/sptr_magic.h>
20 #include <gnuradio/thread/thread.h>
21 #include <boost/thread/condition_variable.hpp>
22 #include <deque>
23 #include <functional>
24 #include <map>
25 #include <string>
26 
28 
29 namespace gr {
30 
31 /*!
32  * \brief The abstract base class for all signal processing blocks.
33  * \ingroup internal
34  *
35  * Basic blocks are the bare abstraction of an entity that has a
36  * name, a set of inputs and outputs, and a message queue. These
37  * are never instantiated directly; rather, this is the abstract
38  * parent class of both gr_hier_block, which is a recursive
39  * container, and block, which implements actual signal
40  * processing functions.
41  */
43  public std::enable_shared_from_this<basic_block>
44 {
45  typedef std::function<void(pmt::pmt_t)> msg_handler_t;
46 
47 private:
48  typedef std::map<pmt::pmt_t, msg_handler_t, pmt::comparator> d_msg_handlers_t;
49  d_msg_handlers_t d_msg_handlers;
50 
51  typedef std::deque<pmt::pmt_t> msg_queue_t;
52  typedef std::map<pmt::pmt_t, msg_queue_t, pmt::comparator> msg_queue_map_t;
53  typedef std::map<pmt::pmt_t, msg_queue_t, pmt::comparator>::iterator
54  msg_queue_map_itr;
55 
56  gr::thread::mutex mutex; //< protects all vars
57 
58 protected:
59  friend class flowgraph;
60  friend class flat_flowgraph; // TODO: will be redundant
61  friend class tpb_thread_body;
62 
63  enum vcolor { WHITE, GREY, BLACK };
64 
65  std::string d_name;
70  std::string d_symbol_name;
71  std::string d_symbol_alias;
73  bool d_rpc_set;
74 
75  /*! Used by blocks to access the logger system.
76  */
77  gr::logger_ptr d_logger; //! Default logger
78  gr::logger_ptr d_debug_logger; //! Verbose logger
79 
80  msg_queue_map_t msg_queue;
81  std::vector<rpcbasic_sptr> d_rpc_vars; // container for all RPC variables
82 
83  basic_block(void) {} // allows pure virtual interface sub-classes
84 
85  //! Protected constructor prevents instantiation by non-derived classes
86  basic_block(const std::string& name,
87  gr::io_signature::sptr input_signature,
88  gr::io_signature::sptr output_signature);
89 
90  //! may only be called during constructor
91  void set_input_signature(gr::io_signature::sptr iosig) { d_input_signature = iosig; }
92 
93  //! may only be called during constructor
95  {
96  d_output_signature = iosig;
97  }
98 
99  /*!
100  * \brief Allow the flowgraph to set for sorting and partitioning
101  */
102  void set_color(vcolor color) { d_color = color; }
103  vcolor color() const { return d_color; }
104 
105  /*!
106  * \brief Tests if there is a handler attached to port \p which_port
107  */
108  virtual bool has_msg_handler(pmt::pmt_t which_port)
109  {
110  return (d_msg_handlers.find(which_port) != d_msg_handlers.end());
111  }
112 
113  /*
114  * This function is called by the runtime system to dispatch messages.
115  *
116  * The thread-safety guarantees mentioned in set_msg_handler are
117  * implemented by the callers of this method.
118  */
119  virtual void dispatch_msg(pmt::pmt_t which_port, pmt::pmt_t msg)
120  {
121  // AA Update this
122  if (has_msg_handler(which_port)) { // Is there a handler?
123  d_msg_handlers[which_port](msg); // Yes, invoke it.
124  }
125  }
126 
127  // Message passing interface
129 
130  /*!
131  * \brief This is meant to be called by derived classes (e.g. block) to get
132  * a shared pointer internally. This is needed because
133  * std::enable_shared_from_this doesn't seem to work with derived classes
134  * in an inheritance hierarchy.
135  */
136  template <typename Derived>
137  std::shared_ptr<Derived> shared_from_base()
138  {
139  return std::static_pointer_cast<Derived>(shared_from_this());
140  }
141 
142 public:
144  ~basic_block() override;
145  long unique_id() const { return d_unique_id; }
146  long symbolic_id() const { return d_symbolic_id; }
147 
148  /*! The name of the block */
149  std::string name() const { return d_name; }
150 
151  /*!
152  * The sybolic name of the block, which is used in the
153  * block_registry. The name is assigned by the block's constructor
154  * and never changes during the life of the block.
155  */
156  std::string symbol_name() const { return d_symbol_name; }
157  std::string identifier() const
158  {
159  return this->name() + "(" + std::to_string(this->unique_id()) + ")";
160  }
161 
162  gr::io_signature::sptr input_signature() const { return d_input_signature; }
163  gr::io_signature::sptr output_signature() const { return d_output_signature; }
164  basic_block_sptr to_basic_block(); // Needed for Python type coercion
165 
166  /*!
167  * True if the block has an alias (see set_block_alias).
168  */
169  bool alias_set() const { return !d_symbol_alias.empty(); }
170 
171  /*!
172  * Returns the block's alias as a string.
173  */
174  std::string alias() const { return alias_set() ? d_symbol_alias : symbol_name(); }
175 
176  /*!
177  * Returns the block's alias as PMT.
178  */
179  pmt::pmt_t alias_pmt() const { return pmt::intern(alias()); }
180 
181  /*!
182  * Set's a new alias for the block; also adds an entry into the
183  * block_registry to get the block using either the alias or the
184  * original symbol name.
185  */
186  void set_block_alias(std::string name);
187 
188  // ** Message passing interface **
192  void message_port_sub(pmt::pmt_t port_id, pmt::pmt_t target);
193  void message_port_unsub(pmt::pmt_t port_id, pmt::pmt_t target);
194 
195  virtual bool message_port_is_hier(pmt::pmt_t port_id)
196  {
197  (void)port_id;
198  return false;
199  }
200  virtual bool message_port_is_hier_in(pmt::pmt_t port_id)
201  {
202  (void)port_id;
203  return false;
204  }
205  virtual bool message_port_is_hier_out(pmt::pmt_t port_id)
206  {
207  (void)port_id;
208  return false;
209  }
210 
211  /*!
212  * \brief Get input message port names.
213  *
214  * Returns the available input message ports for a block. The
215  * return object is a PMT vector that is filled with PMT symbols.
216  */
218 
219  /*!
220  * \brief Get output message port names.
221  *
222  * Returns the available output message ports for a block. The
223  * return object is a PMT vector that is filled with PMT symbols.
224  */
226 
227  /*!
228  * Accept msg, place in queue, arrange for thread to be awakened if it's not already.
229  */
230  void _post(pmt::pmt_t which_port, pmt::pmt_t msg);
231 
232  //! is the queue empty?
233  bool empty_p(pmt::pmt_t which_port)
234  {
235  if (msg_queue.find(which_port) == msg_queue.end())
236  throw std::runtime_error("port does not exist!");
237  return msg_queue[which_port].empty();
238  }
239  bool empty_p()
240  {
241  bool rv = true;
242  for (const auto& i : msg_queue) {
243  rv &= msg_queue[i.first].empty();
244  }
245  return rv;
246  }
247 
248  //! are all msg ports with handlers empty?
249  bool empty_handled_p(pmt::pmt_t which_port)
250  {
251  return (empty_p(which_port) || !has_msg_handler(which_port));
252  }
254  {
255  bool rv = true;
256  for (const auto& i : msg_queue) {
257  rv &= empty_handled_p(i.first);
258  }
259  return rv;
260  }
261 
262  //! How many messages in the queue?
263  size_t nmsgs(pmt::pmt_t which_port)
264  {
265  if (msg_queue.find(which_port) == msg_queue.end())
266  throw std::runtime_error("port does not exist!");
267  return msg_queue[which_port].size();
268  }
269 
270  //| Acquires and release the mutex
272  /*!
273  * \returns returns pmt at head of queue or pmt::pmt_t() if empty.
274  */
276 
277  msg_queue_t::iterator get_iterator(pmt::pmt_t which_port)
278  {
279  return msg_queue[which_port].begin();
280  }
281 
282  void erase_msg(pmt::pmt_t which_port, msg_queue_t::iterator it)
283  {
284  msg_queue[which_port].erase(it);
285  }
286 
287  virtual bool has_msg_port(pmt::pmt_t which_port)
288  {
289  if (msg_queue.find(which_port) != msg_queue.end()) {
290  return true;
291  }
292  if (pmt::dict_has_key(d_message_subscribers, which_port)) {
293  return true;
294  }
295  return false;
296  }
297 
298  const msg_queue_map_t& get_msg_map(void) const { return msg_queue; }
299 
300 #ifdef GR_CTRLPORT
301  /*!
302  * \brief Add an RPC variable (get or set).
303  *
304  * Using controlport, we create new getters/setters and need to
305  * store them. Each block has a vector to do this, and these never
306  * need to be accessed again once they are registered with the RPC
307  * backend. This function takes a
308  * std::shared_sptr<rpcbasic_base> so that when the block is
309  * deleted, all RPC registered variables are cleaned up.
310  *
311  * \param s an rpcbasic_sptr of the new RPC variable register to store.
312  */
313  void add_rpc_variable(rpcbasic_sptr s) { d_rpc_vars.push_back(s); }
314 #endif /* GR_CTRLPORT */
315 
316  /*!
317  * \brief Set up the RPC registered variables.
318  *
319  * This must be overloaded by a block that wants to use
320  * controlport. This is where rpcbasic_register_{get,set} pointers
321  * are created, which then get wrapped as shared pointers
322  * (rpcbasic_sptr(...)) and stored using add_rpc_variable.
323  */
324  virtual void setup_rpc(){};
325 
326  /*!
327  * \brief Ask if this block has been registered to the RPC.
328  *
329  * We can only register a block once, so we use this to protect us
330  * from calling it multiple times.
331  */
332  bool is_rpc_set() { return d_rpc_set; }
333 
334  /*!
335  * \brief When the block is registered with the RPC, set this.
336  */
337  void rpc_set() { d_rpc_set = true; }
338 
339  /*!
340  * \brief Confirm that ninputs and noutputs is an acceptable combination.
341  *
342  * \param ninputs number of input streams connected
343  * \param noutputs number of output streams connected
344  *
345  * \returns true if this is a valid configuration for this block.
346  *
347  * This function is called by the runtime system whenever the
348  * topology changes. Most classes do not need to override this.
349  * This check is in addition to the constraints specified by the
350  * input and output gr::io_signatures.
351  */
352  virtual bool check_topology(int ninputs, int noutputs)
353  {
354  (void)ninputs;
355  (void)noutputs;
356  return true;
357  }
358 
359  /*!
360  * \brief Set the callback that is fired when messages are available.
361  *
362  * \p msg_handler can be any kind of function pointer or function object
363  * that has the signature:
364  * <pre>
365  * void msg_handler(pmt::pmt msg);
366  * </pre>
367  *
368  * (You may want to use boost::bind to massage your callable into
369  * the correct form. See gr::blocks::nop for an example that sets
370  * up a class method as the callback.)
371  *
372  * Blocks that desire to handle messages must call this method in
373  * their constructors to register the handler that will be invoked
374  * when messages are available.
375  *
376  * If the block inherits from block, the runtime system will
377  * ensure that msg_handler is called in a thread-safe manner, such
378  * that work and msg_handler will never be called concurrently.
379  * This allows msg_handler to update state variables without
380  * having to worry about thread-safety issues with work,
381  * general_work or another invocation of msg_handler.
382  *
383  * If the block inherits from hier_block2, the runtime system
384  * will ensure that no reentrant calls are made to msg_handler.
385  */
386  template <typename T>
388  {
389  if (msg_queue.find(which_port) == msg_queue.end()) {
390  throw std::runtime_error(
391  "attempt to set_msg_handler() on bad input message port!");
392  }
393  d_msg_handlers[which_port] = msg_handler_t(msg_handler);
394  }
395 
396  virtual void set_processor_affinity(const std::vector<int>& mask) = 0;
397 
398  virtual void unset_processor_affinity() = 0;
399 
400  virtual std::vector<int> processor_affinity() = 0;
401 
402  virtual void set_log_level(const std::string& level) = 0;
403 
404  virtual std::string log_level() = 0;
405 };
406 
407 inline bool operator<(basic_block_sptr lhs, basic_block_sptr rhs)
408 {
409  return lhs->unique_id() < rhs->unique_id();
410 }
411 
412 typedef std::vector<basic_block_sptr> basic_block_vector_t;
413 typedef std::vector<basic_block_sptr>::iterator basic_block_viter_t;
414 
416 
417 inline std::ostream& operator<<(std::ostream& os, basic_block_sptr basic_block)
418 {
419  os << basic_block->identifier();
420  return os;
421 }
422 
423 } /* namespace gr */
424 
425 #endif /* INCLUDED_GR_BASIC_BLOCK_H */
The abstract base class for all signal processing blocks.
Definition: basic_block.h:44
gr::io_signature::sptr input_signature() const
Definition: basic_block.h:162
virtual void set_log_level(const std::string &level)=0
bool empty_handled_p(pmt::pmt_t which_port)
are all msg ports with handlers empty?
Definition: basic_block.h:249
bool is_rpc_set()
Ask if this block has been registered to the RPC.
Definition: basic_block.h:332
gr::logger_ptr d_debug_logger
Default logger.
Definition: basic_block.h:78
pmt::pmt_t message_subscribers(pmt::pmt_t port)
virtual bool message_port_is_hier_out(pmt::pmt_t port_id)
Definition: basic_block.h:205
void set_color(vcolor color)
Allow the flowgraph to set for sorting and partitioning.
Definition: basic_block.h:102
std::string d_symbol_alias
Definition: basic_block.h:71
long unique_id() const
Definition: basic_block.h:145
msg_queue_t::iterator get_iterator(pmt::pmt_t which_port)
Definition: basic_block.h:277
void message_port_register_in(pmt::pmt_t port_id)
void set_input_signature(gr::io_signature::sptr iosig)
may only be called during constructor
Definition: basic_block.h:91
basic_block(const std::string &name, gr::io_signature::sptr input_signature, gr::io_signature::sptr output_signature)
Protected constructor prevents instantiation by non-derived classes.
void message_port_pub(pmt::pmt_t port_id, pmt::pmt_t msg)
size_t nmsgs(pmt::pmt_t which_port)
How many messages in the queue?
Definition: basic_block.h:263
virtual void set_processor_affinity(const std::vector< int > &mask)=0
virtual bool message_port_is_hier_in(pmt::pmt_t port_id)
Definition: basic_block.h:200
gr::logger_ptr d_logger
Definition: basic_block.h:77
msg_queue_map_t msg_queue
Verbose logger.
Definition: basic_block.h:80
basic_block(void)
Definition: basic_block.h:83
~basic_block() override
long d_symbolic_id
Definition: basic_block.h:69
bool empty_handled_p()
Definition: basic_block.h:253
virtual std::string log_level()=0
void set_output_signature(gr::io_signature::sptr iosig)
may only be called during constructor
Definition: basic_block.h:94
std::string identifier() const
Definition: basic_block.h:157
long symbolic_id() const
Definition: basic_block.h:146
pmt::pmt_t alias_pmt() const
Definition: basic_block.h:179
virtual void setup_rpc()
Set up the RPC registered variables.
Definition: basic_block.h:324
void set_msg_handler(pmt::pmt_t which_port, T msg_handler)
Set the callback that is fired when messages are available.
Definition: basic_block.h:387
basic_block_sptr to_basic_block()
gr::io_signature::sptr d_output_signature
Definition: basic_block.h:67
gr::io_signature::sptr d_input_signature
Definition: basic_block.h:66
virtual bool message_port_is_hier(pmt::pmt_t port_id)
Definition: basic_block.h:195
long d_unique_id
Definition: basic_block.h:68
virtual bool has_msg_port(pmt::pmt_t which_port)
Definition: basic_block.h:287
bool d_rpc_set
Definition: basic_block.h:73
virtual void dispatch_msg(pmt::pmt_t which_port, pmt::pmt_t msg)
Definition: basic_block.h:119
virtual std::vector< int > processor_affinity()=0
std::string symbol_name() const
Definition: basic_block.h:156
std::string alias() const
Definition: basic_block.h:174
void _post(pmt::pmt_t which_port, pmt::pmt_t msg)
bool alias_set() const
Definition: basic_block.h:169
void message_port_register_out(pmt::pmt_t port_id)
void rpc_set()
When the block is registered with the RPC, set this.
Definition: basic_block.h:337
virtual void unset_processor_affinity()=0
vcolor
Definition: basic_block.h:63
virtual bool has_msg_handler(pmt::pmt_t which_port)
Tests if there is a handler attached to port which_port.
Definition: basic_block.h:108
virtual bool check_topology(int ninputs, int noutputs)
Confirm that ninputs and noutputs is an acceptable combination.
Definition: basic_block.h:352
void insert_tail(pmt::pmt_t which_port, pmt::pmt_t msg)
void erase_msg(pmt::pmt_t which_port, msg_queue_t::iterator it)
Definition: basic_block.h:282
void set_block_alias(std::string name)
void message_port_unsub(pmt::pmt_t port_id, pmt::pmt_t target)
pmt::pmt_t message_ports_out()
Get output message port names.
std::string d_name
Definition: basic_block.h:65
void message_port_sub(pmt::pmt_t port_id, pmt::pmt_t target)
std::shared_ptr< Derived > shared_from_base()
This is meant to be called by derived classes (e.g. block) to get a shared pointer internally....
Definition: basic_block.h:137
gr::io_signature::sptr output_signature() const
Definition: basic_block.h:163
std::vector< rpcbasic_sptr > d_rpc_vars
Definition: basic_block.h:81
vcolor color() const
Definition: basic_block.h:103
const msg_queue_map_t & get_msg_map(void) const
Definition: basic_block.h:298
pmt::pmt_t message_ports_in()
Get input message port names.
bool empty_p(pmt::pmt_t which_port)
is the queue empty?
Definition: basic_block.h:233
bool empty_p()
Definition: basic_block.h:239
pmt::pmt_t d_message_subscribers
Definition: basic_block.h:128
std::string name() const
Definition: basic_block.h:149
std::string d_symbol_name
Definition: basic_block.h:70
pmt::pmt_t delete_head_nowait(pmt::pmt_t which_port)
vcolor d_color
Definition: basic_block.h:72
Class representing a directed, acyclic graph of basic blocks.
Definition: flowgraph.h:150
std::shared_ptr< io_signature > sptr
Definition: io_signature.h:40
Accepts messages and inserts them into a message queue, then notifies subclass gr::basic_block there ...
Definition: msg_accepter.h:25
abstract class of message handlers
Definition: msg_handler.h:27
thread-safe message queue
Definition: msg_queue.h:25
#define GR_RUNTIME_API
Definition: gnuradio-runtime/include/gnuradio/api.h:18
GR_RUNTIME_API const pmt::pmt_t msg()
boost::mutex mutex
Definition: thread.h:37
GNU Radio logging wrapper.
Definition: basic_block.h:29
std::shared_ptr< logger > logger_ptr
Definition: logger.h:207
std::vector< basic_block_sptr > basic_block_vector_t
Definition: basic_block.h:412
bool operator<(basic_block_sptr lhs, basic_block_sptr rhs)
Definition: basic_block.h:407
std::vector< basic_block_sptr >::iterator basic_block_viter_t
Definition: basic_block.h:413
GR_RUNTIME_API long basic_block_ncurrently_allocated()
std::ostream & operator<<(std::ostream &os, basic_block_sptr basic_block)
Definition: basic_block.h:417
PMT_API bool dict_has_key(const pmt_t &dict, const pmt_t &key)
Return true if key exists in dict.
PMT_API pmt_t intern(const std::string &s)
Alias for pmt_string_to_symbol.
std::shared_ptr< pmt_base > pmt_t
typedef for shared pointer (transparent reference counting).
Definition: pmt.h:84