This source file includes following definitions.
- doCompliment
- formatNumber
- MeetingPlace_Init
- Meet
- CreatureThreadRun
- Creature_Init
- Creature_getResult
- runGame
- printColours
- printColoursTable
- main
#include <stdlib.h>
#include <stdio.h>
#include <pthread.h>
enum Colour
{
blue = 0,
red = 1,
yellow = 2,
Invalid = 3
};
const char* ColourName[] = {"blue", "red", "yellow"};
const int STACK_SIZE = 32*1024;
typedef unsigned int BOOL;
const BOOL TRUE = 1;
const BOOL FALSE = 0;
int CreatureID = 0;
enum Colour doCompliment(enum Colour c1, enum Colour c2)
{
switch (c1)
{
case blue:
switch (c2)
{
case blue:
return blue;
case red:
return yellow;
case yellow:
return red;
default:
goto errlb;
}
case red:
switch (c2)
{
case blue:
return yellow;
case red:
return red;
case yellow:
return blue;
default:
goto errlb;
}
case yellow:
switch (c2)
{
case blue:
return red;
case red:
return blue;
case yellow:
return yellow;
default:
goto errlb;
}
default:
break;
}
errlb:
printf("Invalid colour\n");
exit( 1 );
}
char* formatNumber(int n, char* outbuf)
{
int ochar = 0, ichar = 0;
int i;
char tmp[64];
const char* NUMBERS[] =
{
"zero", "one", "two", "three", "four", "five",
"six", "seven", "eight", "nine"
};
ichar = sprintf(tmp, "%d", n);
for (i = 0; i < ichar; i++)
ochar += sprintf( outbuf + ochar, " %s", NUMBERS[ tmp[i] - '0' ] );
return outbuf;
}
struct MeetingPlace
{
pthread_mutex_t mutex;
int meetingsLeft;
struct Creature* firstCreature;
};
struct Creature
{
pthread_t ht;
pthread_attr_t stack_att;
struct MeetingPlace* place;
int count;
int sameCount;
enum Colour colour;
int id;
BOOL two_met;
BOOL sameid;
};
void MeetingPlace_Init(struct MeetingPlace* m, int meetings )
{
pthread_mutex_init( &m->mutex, 0 );
m->meetingsLeft = meetings;
m->firstCreature = 0;
}
BOOL Meet( struct Creature* cr)
{
BOOL retval = TRUE;
struct MeetingPlace* mp = cr->place;
pthread_mutex_lock( &(mp->mutex) );
if ( mp->meetingsLeft > 0 )
{
if ( mp->firstCreature == 0 )
{
cr->two_met = FALSE;
mp->firstCreature = cr;
}
else
{
struct Creature* first;
enum Colour newColour;
first = mp->firstCreature;
newColour = doCompliment( cr->colour, first->colour );
cr->sameid = cr->id == first->id;
cr->colour = newColour;
cr->two_met = TRUE;
first->sameid = cr->sameid;
first->colour = newColour;
first->two_met = TRUE;
mp->firstCreature = 0;
mp->meetingsLeft--;
}
}
else
retval = FALSE;
pthread_mutex_unlock( &(mp->mutex) );
return retval;
}
void* CreatureThreadRun(void* param)
{
struct Creature* cr = (struct Creature*)param;
while (TRUE)
{
if ( Meet(cr) )
{
while (cr->two_met == FALSE)
sched_yield();
if (cr->sameid)
cr->sameCount++;
cr->count++;
}
else
break;
}
return 0;
}
void Creature_Init( struct Creature *cr, struct MeetingPlace* place, enum Colour colour )
{
cr->place = place;
cr->count = cr->sameCount = 0;
cr->id = ++CreatureID;
cr->colour = colour;
cr->two_met = FALSE;
pthread_attr_init( &cr->stack_att );
pthread_attr_setstacksize( &cr->stack_att, STACK_SIZE );
pthread_create( &cr->ht, &cr->stack_att, &CreatureThreadRun, (void*)(cr) );
}
char* Creature_getResult(struct Creature* cr, char* str)
{
char numstr[256];
formatNumber(cr->sameCount, numstr);
sprintf( str, "%u%s", cr->count, numstr );
return str;
}
void runGame( int n_meeting, int ncolor, const enum Colour* colours )
{
int i;
int total = 0;
char str[256];
struct MeetingPlace place;
struct Creature *creatures = (struct Creature*) calloc( ncolor, sizeof(struct Creature) );
MeetingPlace_Init( &place, n_meeting );
for (i = 0; i < ncolor; i++)
{
printf( "%s ", ColourName[ colours[i] ] );
Creature_Init( &(creatures[i]), &place, colours[i] );
}
printf("\n");
for (i = 0; i < ncolor; i++)
pthread_join( creatures[i].ht, 0 );
for (i = 0; i < ncolor; i++)
{
printf( "%s\n", Creature_getResult(&(creatures[i]), str) );
total += creatures[i].count;
}
printf( "%s\n\n", formatNumber(total, str) );
pthread_mutex_destroy( &place.mutex );
free( creatures );
}
void printColours( enum Colour c1, enum Colour c2 )
{
printf( "%s + %s -> %s\n",
ColourName[c1],
ColourName[c2],
ColourName[doCompliment(c1, c2)] );
}
void printColoursTable(void)
{
printColours(blue, blue);
printColours(blue, red);
printColours(blue, yellow);
printColours(red, blue);
printColours(red, red);
printColours(red, yellow);
printColours(yellow, blue);
printColours(yellow, red);
printColours(yellow, yellow);
}
int main(int argc, char** argv)
{
int n = (argc == 2) ? atoi(argv[1]) : 600;
printColoursTable();
printf("\n");
const enum Colour r1[] = { blue, red, yellow };
const enum Colour r2[] = { blue, red, yellow,
red, yellow, blue,
red, yellow, red, blue };
runGame( n, sizeof(r1) / sizeof(r1[0]), r1 );
runGame( n, sizeof(r2) / sizeof(r2[0]), r2 );
return 0;
}