| #ifndef COROUTINE_H |
| #define COROUTINE_H |
|
| #include <stdbool.h> |
| #include <stddef.h> |
| #include <stdint.h> |
|
| /////////////////////////////////////////////////////////////////////////////// |
| // Coroutine |
| // |
| // Coroutines for C, based on setjmp/longjmp. |
| // Thread safe - each thread has its own coroutine system |
| // Coroutines are cooperatively scheduled |
| // Coroutines have their own stack (currently 16K each) |
| // A coroutine can be continued, queried, or deleted on a different thread. |
| // |
| // Usage: |
| // Coroutine_StartSystem(); // call once per thread before using coroutines |
| // Coroutine *co = Coroutine_New(start_function); |
| // void *result; |
| // if (Coroutine_Run(co, initial_value, &result)){} |
| // // Handle the failure |
| // | |
| // Coroutine_Delete(co); |
| // Coroutine_StopSystem(); // call once per thread when done with coroutines |
| // |
| // Inside the coroutine function: |
| // void *value = Coroutine_Yield(yield_value, on_yield, this); |
| // ... |
| // return return_value; |
| // |
| // To create a coroutine: |
| // Coroutine *co = Coroutine_New(start_function); |
| // To start or continue a coroutine: |
| // void *result = Coroutine_Continue(co, value, early); |
| // // early=true puts the coroutine at the head of the run queue |
| // // early=false puts the coroutine at the tail of the run queue |
| // To yield from inside a coroutine: |
| // void *value = Coroutine_Yield(yield_value, on_yield, this); |
| // // on_yield is called before the next coroutine is run |
| // // 'this' is passed to on_yield as its parameter |
| // // value is the value passed to Coroutine_Continue |
| // To delete a coroutine: |
| // Coroutine_Delete(co); |
| // To get the value yielded from, or returned by a corotuine: |
| // void *value = Coroutine_GetValue(co); |
| // To get the currently running coroutine (NULL if none): |
| // Coroutine *co = Coroutine_GetActive(); |
| // To check if a coroutine is currently running: |
| // bool running = Coroutine_IsRunning(co); |
| // |
| // Notes: |
| // Coroutine is not expected to be used directly, but as a foundation for |
| // higher level constructs such as Generators, Async, etc. |
| // |
| /////////////////////////////////////////////////////////////////////////////// |
|
|
| // The stack is used as follows: |
| // |
| // Note: the stack is assumed to grow downwards through memory |
| // |
| // (low memory) |
| // |
| // <- limit. When set this and lower memory addresses are assumed to be unavailable for stack use |
| // (- lowest address usable by the stack -) |
| // . . |
| // . . |
| // | coroutine stack | |
| // +------------------+ |
| // | coroutine header | <- 'tip' coroutine (latest allocated Coroutine) |
| // +------------------+ |
| // | coroutine stack | |
| // +------------------+ |
| // | coroutine header | <- 'active' Coroutine (the one currently running - could be 'tip') |
| // +------------------+ |
| // | coroutine stack | |
| // +------------------+ |
| // | coroutine header | |
| // +------------------+ |
| // | coroutine stack | |
| // +------------------+ |
| // | coroutine header | |
| // +------------------+ |
| // | startup space | <- set aside by Coroutine_StartSystem |
| // +------------------+ |
| // | caller | <- This calls Coroutine_StartSystem etc |
| // +------------------+ |
| // | used stack | |
| // +------------------+ <- stack 'bottom'; highest address used by the stack |
| // (high memory) |
|
| // No coroutine will ask for less stack than this |
| #ifndef COROUTINE_MINIMUM_STACK_SIZE |
| #define COROUTINE_MINIMUM_STACK_SIZE (4096 * sizeof(void *)) |
| #endif |
|
| // Before Coroutine has New()'ed a Coroutine, this amount of stack |
| // is set aside for workings between the New() and Run(): |
| #ifndef COROUTINE_STARTUP_STACK_SIZE |
| #define COROUTINE_STARTUP_STACK_SIZE (128 * sizeof(void *)) |
| #endif |
|
| // When allocating space for a coroutine stack, fill it with guard pattern |
| // so that lowest_headroom in the Coroutine_Report can be worked out |
| #ifndef COROUTINE_RECORD_LOWEST_HEADROOM |
| #define COROUTINE_RECORD_LOWEST_HEADROOM 1 |
| #endif |
|
| // Returned by Coroutine_StopSystem(), this summarises the coroutine session |
| typedef struct Coroutine_Report { |
| unsigned coroutines_created; |
| unsigned coroutines_pool_size; |
| size_t lowest_headroom; |
| size_t largest_stack; |
| } Coroutine_Report; |
|
| typedef struct Coroutine Coroutine; |
|
| typedef void (*Coroutine_YieldCallback)(void *me); |
| typedef void *(*Coroutine_Start)(void *); |
|
| extern void Coroutine_StartSystem(void); |
| extern void Coroutine_SetStackLimit(void *); |
| extern Coroutine_Report Coroutine_StopSystem(void); |
| extern Coroutine *Coroutine_New(size_t size, Coroutine_Start start); |
| extern void Coroutine_Run_Coroutine(Coroutine *cor, void *value); |
| extern bool Coroutine_Run(size_t size, Coroutine_Start start, void *value, void **result); |
| extern void Coroutine_Delete(Coroutine *cor); |
| extern void Coroutine_Continue(Coroutine *cor, void *value, bool early); |
| extern void *Coroutine_Yield(void *value, Coroutine_YieldCallback on_yield, void *me); |
| extern void *Coroutine_GetValue(Coroutine *cor); |
| extern Coroutine *Coroutine_GetActive(void); |
| extern intptr_t Coroutine_GetStackHeadroom(void); |
| extern void *Coroutine_GetStackHWM(void); |
| extern void Coroutine_ClearStackForHWM(void); |
| extern bool Coroutine_CanStartCoroutine(size_t size); |
| extern void *Coroutine_GetCStackTop(void); |
| extern bool Coroutine_Chain(size_t size, Coroutine_Start start, void *value, void **result); |
| extern bool Coroutine_IsStarted(void); |
| extern bool Coroutine_IsRunning(Coroutine *cor); |
| extern bool Coroutine_IsComplete(Coroutine *cor); |
|
| extern void _Coroutine_Dump(void); |
|
| #endif |
|