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Mail.h
1 /* mbed Microcontroller Library
2  * Copyright (c) 2006-2019 ARM Limited
3  * SPDX-License-Identifier: MIT
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a copy
6  * of this software and associated documentation files (the "Software"), to deal
7  * in the Software without restriction, including without limitation the rights
8  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9  * copies of the Software, and to permit persons to whom the Software is
10  * furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  */
23 #ifndef MAIL_H
24 #define MAIL_H
25 
26 #include <stdint.h>
27 #include <string.h>
28 
29 #include "rtos/Queue.h"
30 #include "rtos/MemoryPool.h"
31 #include "rtos/mbed_rtos_types.h"
32 #include "rtos/internal/mbed_rtos_storage.h"
33 #include "rtos/internal/mbed_rtos1_types.h"
34 
35 #include "platform/mbed_toolchain.h"
36 #include "platform/mbed_assert.h"
37 #include "platform/NonCopyable.h"
38 
39 #ifndef MBED_NO_GLOBAL_USING_DIRECTIVE
40 using namespace rtos;
41 #endif
42 
43 #if MBED_CONF_RTOS_PRESENT || defined(DOXYGEN_ONLY)
44 
45 namespace rtos {
46 /** \addtogroup rtos-public-api */
47 /** @{*/
48 
49 /**
50  * \defgroup rtos_Mail Mail class
51  * @{
52  */
53 
54 /** The Mail class allows you to control, send, receive or wait for mail.
55  * A mail is a memory block that is sent to a thread or interrupt service routine (ISR).
56  * @tparam T Data type of a single mail message element.
57  * @tparam queue_sz Maximum number of mail messages in queue.
58  *
59  * @note
60  * Memory considerations: The mail data store and control structures are part of this class - they do not (themselves)
61  * allocate memory on the heap, both for the Mbed OS and underlying RTOS objects (static or dynamic RTOS memory
62  * pools are not being used).
63  *
64  * @note
65  * Bare metal profile: This class is not supported.
66  */
67 template<typename T, uint32_t queue_sz>
68 class Mail : private mbed::NonCopyable<Mail<T, queue_sz> > {
69 public:
70  /** Create and initialize Mail queue.
71  *
72  * @note You cannot call this function from ISR context.
73  */
74  Mail() = default;
75 
76  /** Check if the mail queue is empty.
77  *
78  * @return State of queue.
79  * @retval true Mail queue is empty.
80  * @retval false Mail queue contains mail.
81  *
82  * @note You may call this function from ISR context.
83  */
84  bool empty() const
85  {
86  return _queue.empty();
87  }
88 
89  /** Check if the mail queue is full.
90  *
91  * @return State of queue.
92  * @retval true Mail queue is full.
93  * @retval false Mail queue is not full.
94  *
95  * @note You may call this function from ISR context.
96  */
97  bool full() const
98  {
99  return _queue.full();
100  }
101 
102  /** Allocate a memory block of type T, without blocking.
103  *
104  * @param millisec Not used (see note).
105  *
106  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
107  *
108  * @note You may call this function from ISR context.
109  * @note If blocking is required, use Mail::try_alloc_for or Mail::try_alloc_until
110  * @deprecated Replaced with try_alloc. In future alloc() will be an untimed blocking call.
111  */
112  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Replaced with try_alloc. In future alloc() will be an untimed blocking call.")
113  T *alloc(MBED_UNUSED uint32_t millisec = 0)
114  {
115  return try_alloc();
116  }
117 
118  /** Allocate a memory block of type T, without blocking.
119  *
120  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
121  *
122  * @note You may call this function from ISR context.
123  * @note If blocking is required, use Mail::try_alloc_for or Mail::try_alloc_until
124  */
126  {
127  return _pool.try_alloc();
128  }
129 
130  /** Allocate a memory block of type T, optionally blocking.
131  *
132  * @param rel_time Timeout value, or Kernel::wait_for_u32_forever.
133  *
134  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
135  *
136  * @note You may call this function from ISR context if the millisec parameter is set to 0.
137  */
138  T *try_alloc_for(Kernel::Clock::duration_u32 rel_time)
139  {
140  return _pool.try_alloc_for(rel_time);
141  }
142 
143  /** Allocate a memory block of type T, optionally blocking.
144  *
145  * @param millisec Timeout value, or osWaitForever.
146  *
147  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
148  *
149  * @note You may call this function from ISR context if the millisec parameter is set to 0.
150  * @deprecated Pass a chrono duration, not an integer millisecond count. For example use `5s` rather than `5000`.
151  */
152  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Pass a chrono duration, not an integer millisecond count. For example use `5s` rather than `5000`.")
153  T *alloc_for(uint32_t millisec)
154  {
155  return try_alloc_for(std::chrono::duration<uint32_t, std::milli>(millisec));
156  }
157 
158  /** Allocate a memory block of type T, blocking.
159  *
160  * @param abs_time Absolute timeout time, referenced to Kernel::Clock.
161  *
162  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
163  *
164  * @note You cannot call this function from ISR context.
165  * @note the underlying RTOS may have a limit to the maximum wait time
166  * due to internal 32-bit computations, but this is guaranteed to work if the
167  * wait is <= 0x7fffffff milliseconds (~24 days). If the limit is exceeded,
168  * the wait will time out earlier than specified.
169  */
170  T *try_alloc_until(Kernel::Clock::time_point abs_time)
171  {
172  return _pool.try_alloc_until(abs_time);
173  }
174 
175  /** Allocate a memory block of type T, blocking.
176  *
177  * @param millisec Absolute timeout time, referenced to Kernel::get_ms_count().
178  *
179  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
180  *
181  * @note You cannot call this function from ISR context.
182  * @note the underlying RTOS may have a limit to the maximum wait time
183  * due to internal 32-bit computations, but this is guaranteed to work if the
184  * wait is <= 0x7fffffff milliseconds (~24 days). If the limit is exceeded,
185  * the wait will time out earlier than specified.
186  * @deprecated Pass a chrono time_point, not an integer millisecond count. For example use `Kernel::Clock::now() + 5s`
187  * rather than `Kernel::get_ms_count() + 5000`.
188  */
189  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Pass a chrono time_point, not an integer millisecond count. For example use `Kernel::Clock::now() + 5s` rather than `Kernel::get_ms_count() + 5000`.")
190  T *alloc_until(uint64_t millisec)
191  {
192  return try_alloc_until(Kernel::Clock::time_point(std::chrono::duration<uint64_t, std::milli>(millisec)));
193  }
194 
195  /** Allocate a memory block of type T, and set memory block to zero.
196  *
197  * @param millisec Not used (see note).
198  *
199  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
200  *
201  * @note You may call this function from ISR context.
202  * @note If blocking is required, use Mail::try_calloc_for or Mail::try_calloc_until
203  * @deprecated Replaced with try_calloc. In future calloc() will be an untimed blocking call.
204  */
205  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Replaced with try_calloc. In future calloc() will be an untimed blocking call.")
206  T *calloc(MBED_UNUSED uint32_t millisec = 0)
207  {
208  return try_calloc();
209  }
210 
211  /** Allocate a memory block of type T, and set memory block to zero.
212  *
213  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
214  *
215  * @note You may call this function from ISR context.
216  * @note If blocking is required, use Mail::try_calloc_for or Mail::try_calloc_until
217  */
219  {
220  return _pool.try_calloc();
221  }
222 
223  /** Allocate a memory block of type T, optionally blocking, and set memory block to zero.
224  *
225  * @param rel_time Timeout value, or Kernel::wait_for_u32_forever.
226  *
227  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
228  *
229  * @note You may call this function from ISR context if the rel_time parameter is set to 0.
230  */
231  T *try_calloc_for(Kernel::Clock::duration_u32 rel_time)
232  {
233  return _pool.try_calloc_for(rel_time);
234  }
235 
236  /** Allocate a memory block of type T, optionally blocking, and set memory block to zero.
237  *
238  * @param millisec Timeout value, or osWaitForever.
239  *
240  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
241  *
242  * @note You may call this function from ISR context if the millisec parameter is set to 0.
243  * @deprecated Pass a chrono duration, not an integer millisecond count. For example use `5s` rather than `5000`.
244  */
245  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Pass a chrono duration, not an integer millisecond count. For example use `5s` rather than `5000`.")
246  T *calloc_for(uint32_t millisec)
247  {
248  return try_calloc_for(std::chrono::duration<uint32_t, std::milli>(millisec));
249  }
250 
251  /** Allocate a memory block of type T, blocking, and set memory block to zero.
252  *
253  * @param abs_time Absolute timeout time, referenced to Kernel::Clock.
254  *
255  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
256  *
257  * @note You cannot call this function from ISR context.
258  * @note the underlying RTOS may have a limit to the maximum wait time
259  * due to internal 32-bit computations, but this is guaranteed to work if the
260  * wait is <= 0x7fffffff milliseconds (~24 days). If the limit is exceeded,
261  * the wait will time out earlier than specified.
262  */
263  T *try_calloc_until(Kernel::Clock::time_point abs_time)
264  {
265  return _pool.try_calloc_until(abs_time);
266  }
267 
268  /** Allocate a memory block of type T, blocking, and set memory block to zero.
269  *
270  * @param millisec Absolute timeout time, referenced to Kernel::get_ms_count().
271  *
272  * @return Pointer to memory block that you can fill with mail or nullptr in case error.
273  *
274  * @note You cannot call this function from ISR context.
275  * @note the underlying RTOS may have a limit to the maximum wait time
276  * due to internal 32-bit computations, but this is guaranteed to work if the
277  * wait is <= 0x7fffffff milliseconds (~24 days). If the limit is exceeded,
278  * the wait will time out earlier than specified.
279  * @deprecated Pass a chrono time_point, not an integer millisecond count. For example use `Kernel::Clock::now() + 5s`
280  * rather than `Kernel::get_ms_count() + 5000`.
281  */
282  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Pass a chrono time_point, not an integer millisecond count. For example use `Kernel::Clock::now() + 5s` rather than `Kernel::get_ms_count() + 5000`.")
283  T *calloc_until(uint64_t millisec)
284  {
285  return try_calloc_until(Kernel::Clock::time_point(std::chrono::duration<uint64_t, std::milli>(millisec)));
286  }
287 
288  /** Put a mail in the queue.
289  *
290  * @param mptr Memory block previously allocated with Mail::alloc or Mail::calloc.
291  *
292  * @return Status code that indicates the execution status of the function (osOK on success).
293  * See note.
294  *
295  * @note You may call this function from ISR context.
296  * @note As the mail should have already been allocated, and the memory pool is the same size
297  * as the queue, the put operation should always succeed, despite being implemented with
298  * Queue::try_put - there is room in the queue for every mail from the pool. Therefore
299  * use of the return value is deprecated, and the function will return void in future.
300  */
301  osStatus put(T *mptr)
302  {
303  bool ok = _queue.try_put(mptr);
304  MBED_ASSERT(ok);
305  return ok ? osOK : osErrorResource;
306  }
307 
308  /** Get a mail from the queue.
309  *
310  * @param rel_time Timeout value (default: Kernel::wait_for_u32_forever).
311  *
312  * @return Event that contains mail information and status code. The status code
313  * is stored in the status member:
314  * @a osEventMail Mail successfully received.
315  * @a osOK No mail is available (and no timeout was specified).
316  * @a osEventTimeout No mail has arrived during the given timeout period.
317  * @a osErrorParameter A parameter is invalid or outside of a permitted range.
318  *
319  * @note You may call this function from ISR context if the millisec parameter is set to 0.
320  * @deprecated Replaced with try_get and try_get_for. In future get will be an untimed blocking call.
321  */
322  MBED_DEPRECATED_SINCE("mbed-os-6.0.0", "Replaced with try_get and try_get_for. In future get will be an untimed blocking call.")
323  osEvent get(uint32_t millisec = osWaitForever)
324  {
325  osEvent evt = _queue.get(millisec);
326  if (evt.status == osEventMessage) {
327  evt.status = osEventMail;
328  }
329  return evt;
330  }
331 
332  /** Get a mail from the queue.
333  *
334  * @return Pointer to received mail, or nullptr if none was received.
335  *
336  * @note You may call this function from ISR context.
337  */
338  T *try_get()
339  {
340  T *mptr = nullptr;
341  _queue.try_get(&mptr);
342  return mptr;
343  }
344 
345  /** Get a mail from the queue.
346  *
347  * @param rel_time Timeout value or Kernel::wait_for_u32_forever.
348  *
349  * @return Pointer to received mail, or nullptr if none was received.
350  *
351  * @note You may call this function from ISR context if the millisec parameter is set to 0.
352  */
353  T *try_get_for(Kernel::Clock::duration_u32 rel_time)
354  {
355  T *mptr = nullptr;
356  _queue.try_get_for(rel_time, &mptr);
357  return mptr;
358  }
359 
360  /** Free a memory block from a mail.
361  *
362  * @param mptr Pointer to the memory block that was obtained with Mail::get.
363  *
364  * @return Status code that indicates the execution status of the function (osOK on success).
365  *
366  * @note You may call this function from ISR context.
367  */
368  osStatus free(T *mptr)
369  {
370  return _pool.free(mptr);
371  }
372 
373 private:
374  Queue<T, queue_sz> _queue;
376 };
377 
378 /** @}*/
379 /** @}*/
380 
381 }
382 
383 #endif
384 
385 #endif
386 
osStatus put(T *mptr)
Put a mail in the queue.
Definition: Mail.h:301
osEvent get(uint32_t millisec=osWaitForever)
Get a mail from the queue.
Definition: Mail.h:323
Mail()=default
Create and initialize Mail queue.
bool empty() const
Check if the mail queue is empty.
Definition: Mail.h:84
The Queue class represents a collection of objects that are stored first by order of priority...
Definition: Queue.h:66
T * calloc_for(uint32_t millisec)
Allocate a memory block of type T, optionally blocking, and set memory block to zero.
Definition: Mail.h:246
T * try_calloc_for(Kernel::Clock::duration_u32 rel_time)
Allocate a memory block from a memory pool, optionally blocking, and set memory block to zero...
Definition: MemoryPool.h:235
T * try_alloc_for(Kernel::Clock::duration_u32 rel_time)
Allocate a memory block from a memory pool, optionally blocking.
Definition: MemoryPool.h:142
T * try_calloc_until(Kernel::Clock::time_point abs_time)
Allocate a memory block of type T, blocking, and set memory block to zero.
Definition: Mail.h:263
T * calloc_until(uint64_t millisec)
Allocate a memory block of type T, blocking, and set memory block to zero.
Definition: Mail.h:283
T * alloc(MBED_UNUSED uint32_t millisec=0)
Allocate a memory block of type T, without blocking.
Definition: Mail.h:113
Prevents generation of copy constructor and copy assignment operator in derived classes.
Definition: NonCopyable.h:162
T * try_calloc()
Allocate a memory block of type T, and set memory block to zero.
Definition: Mail.h:218
T * try_get()
Get a mail from the queue.
Definition: Mail.h:338
T * try_alloc()
Allocate a memory block of type T, without blocking.
Definition: Mail.h:125
T * alloc_until(uint64_t millisec)
Allocate a memory block of type T, blocking.
Definition: Mail.h:190
T * try_alloc_until(Kernel::Clock::time_point abs_time)
Allocate a memory block of type T, blocking.
Definition: Mail.h:170
The Mail class allows you to control, send, receive or wait for mail.
Definition: Mail.h:68
osStatus free(T *block)
Free a memory block.
Definition: MemoryPool.h:300
#define MBED_ASSERT(expr)
MBED_ASSERT Declare runtime assertions: results in runtime error if condition is false.
Definition: mbed_assert.h:66
T * try_alloc_until(Kernel::Clock::time_point abs_time)
Allocate a memory block from a memory pool, blocking.
Definition: MemoryPool.h:176
osStatus free(T *mptr)
Free a memory block from a mail.
Definition: Mail.h:368
T * try_get_for(Kernel::Clock::duration_u32 rel_time)
Get a mail from the queue.
Definition: Mail.h:353
T * try_alloc()
Allocate a memory block from a memory pool, without blocking.
Definition: MemoryPool.h:117
T * calloc(MBED_UNUSED uint32_t millisec=0)
Allocate a memory block of type T, and set memory block to zero.
Definition: Mail.h:206
T * alloc_for(uint32_t millisec)
Allocate a memory block of type T, optionally blocking.
Definition: Mail.h:153
T * try_calloc_for(Kernel::Clock::duration_u32 rel_time)
Allocate a memory block of type T, optionally blocking, and set memory block to zero.
Definition: Mail.h:231
bool full() const
Check if the mail queue is full.
Definition: Mail.h:97
T * try_alloc_for(Kernel::Clock::duration_u32 rel_time)
Allocate a memory block of type T, optionally blocking.
Definition: Mail.h:138
Definition: TaskBase.h:25
T * try_calloc()
Allocate a memory block from a memory pool, without blocking, and set memory block to zero...
Definition: MemoryPool.h:207
#define MBED_UNUSED
MBED_UNUSED Declare a function argument to be unused, suppressing compiler warnings.
T * try_calloc_until(Kernel::Clock::time_point abs_time)
Allocate a memory block from a memory pool, blocking, and set memory block to zero.
Definition: MemoryPool.h:272
#define MBED_DEPRECATED_SINCE(D, M)
MBED_DEPRECATED("message string") Mark a function declaration as deprecated, if it used then a warnin...
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