libguac  1.6.0
fifo.h
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19 
20 #ifndef GUAC_FIFO_H
21 #define GUAC_FIFO_H
22 
23 #include "fifo-constants.h"
24 #include "fifo-types.h"
25 #include "flag.h"
26 
27 #include <stddef.h>
28 #include <sys/types.h>
29 
45 struct guac_fifo {
46 
54 
58  size_t max_items;
59 
64  size_t item_size;
65 
71  size_t head;
72 
76  size_t item_count;
77 
83  ssize_t items_offset;
84 
85 };
86 
109 void guac_fifo_init(guac_fifo* fifo, void* items,
110  size_t max_items, size_t item_size);
111 
125 void guac_fifo_destroy(guac_fifo* fifo);
126 
142 void guac_fifo_invalidate(guac_fifo* fifo);
143 
154 int guac_fifo_is_valid(guac_fifo* fifo);
155 
170 void guac_fifo_lock(guac_fifo* fifo);
171 
183 void guac_fifo_unlock(guac_fifo* fifo);
184 
201 int guac_fifo_enqueue(guac_fifo* fifo, const void* item);
202 
220 int guac_fifo_enqueue_and_lock(guac_fifo* fifo, const void* item);
221 
238 int guac_fifo_dequeue(guac_fifo* fifo, void* item);
239 
257 int guac_fifo_dequeue_and_lock(guac_fifo* fifo, void* item);
258 
281  void* item, int msec_timeout);
282 
307  void* item, int msec_timeout);
308 
313 #endif
314 
void guac_fifo_unlock(guac_fifo *fifo)
Relinquishes exclusive access to this guac_fifo.
int guac_fifo_enqueue_and_lock(guac_fifo *fifo, const void *item)
Atomically adds a copy of the given item to the end of the given FIFO, signals any waiting threads th...
Provides constants for the abstract FIFO implementation (guac_fifo).
int guac_fifo_timed_dequeue_and_lock(guac_fifo *fifo, void *item, int msec_timeout)
Atomically removes the oldest (first) item from the FIFO, storing a copy of that item within the prov...
ssize_t items_offset
The offset of the first byte of the implementation-specific array of items within this FIFO...
Definition: fifo.h:83
int guac_fifo_timed_dequeue(guac_fifo *fifo, void *item, int msec_timeout)
Removes the oldest (first) item from the FIFO, storing a copy of that item within the provided buffer...
int guac_fifo_dequeue(guac_fifo *fifo, void *item)
Removes the oldest (first) item from the FIFO, storing a copy of that item within the provided buffer...
void guac_fifo_invalidate(guac_fifo *fifo)
Marks the given FIFO as invalid, preventing any further additions or removals from the FIFO...
size_t head
The index of the first item within this FIFO.
Definition: fifo.h:71
int guac_fifo_is_valid(guac_fifo *fifo)
Returns whether the given FIFO is still valid.
Generic integer flag intended for signalling of arbitrary events between processes.
Definition: flag.h:27
size_t max_items
The maximum number of items that may be stored in this FIFO.
Definition: fifo.h:58
void guac_fifo_destroy(guac_fifo *fifo)
Releases all underlying resources used by the given guac_fifo, such as pthread mutexes and conditions...
int guac_fifo_enqueue(guac_fifo *fifo, const void *item)
Adds a copy of the given item to the end of the given FIFO, and signals any waiting threads that the ...
size_t item_count
The current number of items stored within this FIFO.
Definition: fifo.h:76
guac_flag state
The current state of this FIFO.
Definition: fifo.h:53
int guac_fifo_dequeue_and_lock(guac_fifo *fifo, void *item)
Atomically removes the oldest (first) item from the FIFO, storing a copy of that item within the prov...
Generic base structure for a FIFO of arbitrary events.
Definition: fifo.h:45
void guac_fifo_init(guac_fifo *fifo, void *items, size_t max_items, size_t item_size)
Initializes the given guac_fifo such that it may be safely included in shared memory and accessed by ...
void guac_fifo_lock(guac_fifo *fifo)
Acquires exclusive access to this guac_fifo.
size_t item_size
The size of each individual item, in bytes.
Definition: fifo.h:64
Provides type definitions for the abstract FIFO implementation (guac_fifo).