在语言环境中进行可靠的编程。 第2部分-挑战者

MODULE Philo; (* Dining Philosophers Example from Active Oberon Language Report by Patrik Reali *) (* Adapted for running in AOS by Siemargl *) IMPORT Semaphores := Example8, Out; CONST NofPhilo = 5; (* number of philosophers *) VAR fork: ARRAY NofPhilo OF Semaphores.Semaphore; i: LONGINT; TYPE Philosopher = OBJECT VAR first, second: LONGINT; (* forks used by this philosopher *) PROCEDURE & Init(id: LONGINT); BEGIN IF id # NofPhilo-1 THEN first := id; second := (id+1) ELSE first := 0; second := NofPhilo-1 END END Init; PROCEDURE Think; (* Need lock console output *) BEGIN {EXCLUSIVE} Out.Int(first); Out.String(".... Think...."); Out.Ln; END Think; PROCEDURE Eat; BEGIN {EXCLUSIVE} Out.Int(first); Out.String(".... Eat...."); Out.Ln; END Eat; BEGIN {ACTIVE} LOOP Think; fork[first].P; fork[second].P; Eat; fork[first].V; fork[second].V END END Philosopher; VAR philo: ARRAY NofPhilo OF Philosopher; BEGIN FOR i := 0 TO NofPhilo DO NEW(fork[i], INTEGER(i)); NEW(philo[i], i); END; END Philo. Philo.Philo1 ~ 

 -- Code from https://rosettacode.org/wiki/Dining_philosophers#Ordered_mutexes -- ADA95 compatible so can run in ideone.com with Ada.Numerics.Float_Random; use Ada.Numerics.Float_Random; with Ada.Text_IO; use Ada.Text_IO; procedure Test_Dining_Philosophers is type Philosopher is (Aristotle, Kant, Spinoza, Marx, Russel); protected type Fork is entry Grab; procedure Put_Down; private Seized : Boolean := False; end Fork; protected body Fork is entry Grab when not Seized is begin Seized := True; end Grab; procedure Put_Down is begin Seized := False; end Put_Down; end Fork; Life_Span : constant := 20; -- In his life a philosopher eats 20 times task type Person (ID : Philosopher; First, Second : not null access Fork); task body Person is Dice : Generator; begin Reset (Dice); for Life_Cycle in 1..Life_Span loop Put_Line (Philosopher'Image (ID) & " is thinking"); delay Duration (Random (Dice) * 0.100); Put_Line (Philosopher'Image (ID) & " is hungry"); First.Grab; Second.Grab; Put_Line (Philosopher'Image (ID) & " is eating"); delay Duration (Random (Dice) * 0.100); Second.Put_Down; First.Put_Down; end loop; Put_Line (Philosopher'Image (ID) & " is leaving"); end Person; Forks : array (1..5) of aliased Fork; -- Forks for hungry philosophers -- Start philosophers Ph_1 : Person (Aristotle, Forks (1)'Access, Forks (2)'Access); Ph_2 : Person (Kant, Forks (2)'Access, Forks (3)'Access); Ph_3 : Person (Spinoza, Forks (3)'Access, Forks (4)'Access); Ph_4 : Person (Marx, Forks (4)'Access, Forks (5)'Access); Ph_5 : Person (Russel, Forks (1)'Access, Forks (5)'Access); begin null; -- Nothing to do in the main task, just sit and behold end Test_Dining_Philosophers; 

 // compile dmd -betterC import core.sys.windows.windows; import core.stdc.stdio; import core.stdc.stdlib : rand; //import std.typecons; // -impossible ( //import std.string; - impossible extern (Windows) alias btex_fptr = void function(void*) /*nothrow*/; //extern (C) uintptr_t _beginthreadex(void*, uint, btex_fptr, void*, uint, uint*) nothrow; /* Dining Philosophers example for a habr.com * by Siemargl, 2019 * BetterC variant. Compile >dmd -betterC Philo_BetterC.d */ extern (C) uintptr_t _beginthread(btex_fptr, uint stack_size, void *arglist) nothrow; alias HANDLE uintptr_t; alias HANDLE Fork; const philocount = 5; const cycles = 20; HANDLE[philocount] forks; struct Philosopher { const(char)* name; Fork left, right; HANDLE lifethread; } Philosopher[philocount] philos; extern (Windows) void PhilosopherLifeCycle(void* data) nothrow { Philosopher* philo = cast(Philosopher*)data; for (int age = 0; age++ < cycles;) { printf("%s is thinking\n", philo.name); Sleep(rand() % 100); printf("%s is hungry\n", philo.name); WaitForSingleObject(philo.left, INFINITE); WaitForSingleObject(philo.right, INFINITE); printf("%s is eating\n", philo.name); Sleep(rand() % 100); ReleaseMutex(philo.right); ReleaseMutex(philo.left); } printf("%s is leaving\n", philo.name); } extern (C) int main() { version(Windows){} else { static assert(false, "OS not supported"); } philos[0] = Philosopher ("Aristotlet".ptr, forks[0], forks[1], null); philos[1] = Philosopher ("Kant".ptr, forks[1], forks[2], null); philos[2] = Philosopher ("Spinoza".ptr, forks[2], forks[3], null); philos[3] = Philosopher ("Marx".ptr, forks[3], forks[4], null); philos[4] = Philosopher ("Russel".ptr, forks[0], forks[4], null); foreach(ref f; forks) { f = CreateMutex(null, false, null); assert(f); } foreach(ref ph; philos) { ph.lifethread = _beginthread(&PhilosopherLifeCycle, 0, &ph); assert(ph.lifethread); } foreach(ref ph; philos) WaitForSingleObject(ph.lifethread, INFINITE); // Close thread and mutex handles for( auto i = 0; i < philocount; i++ ) { CloseHandle(philos[i].lifethread); CloseHandle(forks[i]); } return 0; } 

 (* Dining Philosophers example for a habr.com * by Siemargl, 2019 * ISO61131 ST language variant. Must be specialized 4 ur PLC * ) CONFIGURATION PLC_1 VAR_GLOBAL Forks : USINT; Philo_1: Philosopher; (* Instance block - static vars *) Philo_2: Philosopher; Philo_3: Philosopher; Philo_4: Philosopher; Philo_5: Philosopher; END_VAR RESOURCE Station_1 ON CPU_1 TASK Task_1 (INTERVAL := T#100MS, PRIORITY := 1); TASK Task_2 (INTERVAL := T#100MS, PRIORITY := 1); TASK Task_3 (INTERVAL := T#100MS, PRIORITY := 1); TASK Task_4 (INTERVAL := T#100MS, PRIORITY := 1); TASK Task_5 (INTERVAL := T#100MS, PRIORITY := 1); PROGRAM Life_1 WITH Task_1: Philo_1(Name := 'Kant', 0, 1, Forks); PROGRAM Life2 WITH Task_2: Philo_2(Name := 'Aristotel', 1, 2, Forks); PROGRAM Life3 WITH Task_3: Philo_3(Name := 'Spinoza', 2, 3, Forks); PROGRAM Life4 WITH Task_4: Philo_4(Name := 'Marx', 3, 4, Forks); PROGRAM Life5 WITH Task_5: Philo_5(Name := 'Russel', 4, 0, Forks); END_RESOURCE END_CONFIGURATION FUNCTION_BLOCK Philosopher; USING SysCpuHandling.library; VAR_INPUT Name: STRING; Left: UINT; Right: UINT; END_VAR VAR_IN_OUT Forks: USINT; END_VAR VAR Thinking: BOOL := TRUE; (* States *) Hungry: BOOL; Eating: BOOL; HaveLeftFork: BOOL; TmThink: TON; TmEating: TON; END_VAR TmThink(In := Thinking; PT := T#3s); TmEating(In := Eating; PT := T#5s); IF Thinking THEN (* Just waiting Timer *) Thinking := NOT TmThink.Q; Hungry := TmThink.Q; ELSIF Hungry (* Try Atomic Lock Forks *) IF HaveLeftFork IF SysCpuTestAndSetBit(Address := Forks, Len := 1, iBit := Right, bSet := 1) = ERR_OK THEN Hungry := FALSE; Eating := TRUE; ELSE RETURN; END_IF ELSIF IF SysCpuTestAndSetBit(Address := Forks, Len := 1, iBit := Left, bSet := 1) = ERR_OK THEN HaveLeftFork := TRUE; ELSE RETURN; END_IF END_IF ELSIF Eating (* Waiting Timer, then lay forks *) IF TmEating.Q THEN Thinking := TRUE; Eating := FALSE; HaveLeftFork := FALSE; SysCpuTestAndSetBit(Address := Forks, Len := 1, iBit := Right, bSet := 0); SysCpuTestAndSetBit(Address := Forks, Len := 1, iBit := Left, bSet := 0); END_IF END_IF END_FUNCTION_BLOCK 

 /* Dining Philosophers example for a habr.com * by Siemargl, 2019 * Safe-C variant. Compile >mk.exe philosafec.c */ from std use console, thread, random; enum philos (ushort) { Aristotle, Kant, Spinoza, Marx, Russell, }; const int cycles = 10; const ushort NUM = 5; uint lived = NUM; packed struct philosopher // 32-bit { philos name; byte left, right; } philosopher philo_body[NUM]; SHARED_OBJECT forks[NUM]; void philosopher_life(philosopher philo) { int age; for (age = 0; age++ < cycles; ) { printf("%s is thinking\n", philo.name'string); delay((uint)rnd(1, 100)); printf("%s is hungry\n", philo.name'string); enter_shared_object(ref forks[philo.left]); enter_shared_object(ref forks[philo.right]); printf("%s is eating\n", philo.name'string); delay((uint)rnd(1, 100)); leave_shared_object(ref forks[philo.right]); leave_shared_object(ref forks[philo.left]); } printf("%s is leaving\n", philo.name'string); InterlockedExchange(ref lived, lived-1); } void main() { philos i; assert philosopher'size == 4; philo_body[0] = {Aristotle, 0, 1}; philo_body[1] = {Kant, 1, 2}; philo_body[2] = {Spinoza, 2, 3}; philo_body[3] = {Marx, 3, 4}; philo_body[4] = {Russell, 0, 4}; for (i = philos'first; i <= philos'last; i++) { assert run philosopher_life(philo_body[(uint)i]) == 0; } while (lived > 0) sleep 0; // until all dies for (i = philos'first; i <= philos'last; i++) { destroy_shared_object(ref forks[(uint)i]); } }