c - 家庭作业——使用信号量和互斥量进行排队

Question

...所以我修复了一下，但它现在说...加速测试:程序跨越时间限制...持续时间:5 秒!(限制 8 秒)!...如果有人有任何想法，这是我的代码......

#ifndef __PROGTEST__
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <semaphore.h>

#define MAX_TERRORISTS   32

typedef struct TImage
 {
   int              m_W;
   int              m_H;
   unsigned char ** m_Data;
 } TIMAGE;

void  TerroristHunter    ( int        databaseSize,
                           TIMAGE  ** database,
                           int        threads,
                           TIMAGE *(* scanner) ( void ),
                           void    (* officer) ( TIMAGE *, int ) );
#endif /* __PROGTEST__ */


/* Vase implementace / your implementation here */
pthread_mutex_t m1;

typedef struct Par {
TIMAGE *(* scanner) ( void );
TIMAGE ** terrorist;
int number_of_terrorists;
void ( *officer) ( TIMAGE *, int );} PAR;

void * function ( void * arg ) {

PAR * a = ( PAR * ) arg;
TIMAGE * image;
int i1, i2, i3, i4, i5, result = 0;

while ( 1 ) {
pthread_mutex_lock ( & m1 );
if (( image = a->scanner()) == NULL ) {pthread_mutex_unlock ( & m1 );break;}
pthread_mutex_unlock ( & m1 );
for ( i5 = 0; i5 < a->number_of_terrorists; i5 ++ ) {
    for ( i1 = 0; i1 <= ( image->m_H - a->terrorist[i5]->m_H ); i1 ++ ) {
        for ( i2 = 0; i2 <= ( image->m_W - a->terrorist[i5]->m_W ); i2 ++ ) {
            if ( ( a->terrorist[i5]->m_Data[0][0] == image->m_Data[i1][i2] ) || ( a->terrorist[i5]->m_Data[0][0] == 255 ) ) {
            for ( i3 = 0; i3 < a->terrorist[i5]->m_H; i3 ++ ) {
                for ( i4 = 0; i4 < a->terrorist[i5]->m_W; i4 ++ ) 
                    if ( ( a->terrorist[i5]->m_Data[i3][i4]!= image->m_Data[i1 + i3][i2 + i4] ) && ( a->terrorist[i5]->m_Data[i3][i4] != 255 ) )
                        break;
                if ( i4 != a->terrorist[i5]->m_W )
                    break; }
            if ( i3 == a->terrorist[i5]->m_H ) {
                result = result + ( 1 << i5 );
                break; } } }
        if ( i3 == a->terrorist[i5]->m_H )
            break; } }
a->officer ( image, result );
result = 0;}
return NULL;
}

void  TerroristHunter    ( int        databaseSize,
                           TIMAGE  ** database,
                           int        threads,
                           TIMAGE *(* scanner) ( void ),
                           void    (* officer) ( TIMAGE *, int ) ) {
PAR * pom = ( PAR * ) malloc ( sizeof ( * pom ) );
int i;

pthread_t * thr = ( pthread_t * ) malloc ( threads * sizeof( * thr ) );
pthread_attr_t Attr; pthread_attr_init ( & Attr ); pthread_attr_setdetachstate ( & Attr, PTHREAD_CREATE_JOINABLE );
pthread_mutex_init ( & m1, NULL );

pom->terrorist = database;
pom->number_of_terrorists = databaseSize;
pom->officer = officer;
pom->scanner = scanner;

for ( i = 0; i < threads; i ++ )
    pthread_create ( & thr[i], & Attr, function, (void * ) pom );
for ( i = 0; i < threads; i ++ )
    pthread_join (thr[i], NULL);

pthread_attr_destroy ( & Attr); pthread_mutex_destroy ( & m1 );
free ( pom );
return; }
#ifndef __PROGTEST__
unsigned char t0r0[] = { 255, 255, 255, 255, 255, 255, 255, 255 };
unsigned char t0r1[] = { 255,  50,  60,  70, 255, 255, 255, 255 };
unsigned char t0r2[] = { 255,  50,  60,  70, 255, 255, 255, 255 };
unsigned char t0r3[] = { 255, 255,  50,  60,  70,  80, 255, 255 };
unsigned char t0r4[] = { 255, 255,  50,  60,  70,  80, 255, 255 };
unsigned char t0r5[] = { 255, 255, 255, 255, 255, 255, 255, 255 };
unsigned char t0r6[] = { 255, 255, 255, 255, 255, 255, 255, 255 };
unsigned char * t0all[] = { t0r0, t0r1, t0r2, t0r3, t0r4, t0r5, t0r6 };
TIMAGE  t0 = { 8, 7, t0all };  /* one sample */

unsigned char t1r0[] = {  10,  20,  30 };
unsigned char t1r1[] = {  20,  50, 255 };
unsigned char t1r2[] = {  80,  50, 255 };
unsigned char * t1all[] = { t1r0, t1r1, t1r2 };
TIMAGE  t1 = { 3, 3, t1all };  /* another sample */

TIMAGE * terrorists[2] = { &t0, &t1};

unsigned char i0r0[] = {   1,   2,   3,   4,   5,   6,   7,   8 };
unsigned char i0r1[] = {   2,  50,  60,  70,   6,   7,   8,   1 };
unsigned char i0r2[] = {   3,  50,  60,  70,   7,  10,  20,  30 };
unsigned char i0r3[] = {   4,  50,  60,  70,   8,  20,  50,   3 };
unsigned char i0r4[] = {   5,   6,  50,  60,  70,  80,  50,   4 };
unsigned char i0r5[] = {   6,   7,  50,  60,  70,  80,   4,   5 };
unsigned char i0r6[] = {   7,   8,   1,   2,   3,   4,   5,   6 };
unsigned char i0r7[] = {   8,   1,   2,   3,   4,   5,   6,   7 };
unsigned char * i0all[] = { i0r0, i0r1, i0r2, i0r3, i0r4, i0r5, i0r6, i0r7 };
TIMAGE i0 = { 8, 8, i0all }; /* t0 and t1 here */

unsigned char i1r0[] = {   1,   2,   3,   4,   5,   6,   7,   8 };
unsigned char i1r1[] = {   2,   3,   4,   5,   6,   7,   8,   1 };
unsigned char i1r2[] = {   3,   4,   5,   6,   7,   8,   1,   2 };
unsigned char i1r3[] = {  10,  20,  30,   7,   8,   1,   2,   3 };
unsigned char i1r4[] = {  20,  50,   7,   8,   1,   2,   3,   4 };
unsigned char i1r5[] = {  80,  50,   8,   1,   2,   3,   4,   5 };
unsigned char i1r6[] = {   7,   8,   1,   2,   3,   4,   5,   6 };
unsigned char * i1all[] = { i1r0, i1r1, i1r2, i1r3, i1r4, i1r5, i1r6 };
TIMAGE i1 = { 8, 7, i1all }; /* t1 here */

unsigned char i2r0[] = {   1,  50,  60,  70,   5,   6 };
unsigned char i2r1[] = {   2,  50,  60,  70,   6,   7 };
unsigned char i2r2[] = {   3,   4,  50,  60,  70,  80 };
unsigned char i2r3[] = {  10,  20,  50,  50,  70,  81 };
unsigned char i2r4[] = {  20,  50,   7,   8,   1,   2 };
unsigned char * i2all[] = { i2r0, i2r1, i2r2, i2r3, i2r4 };
TIMAGE i2 = { 6, 5, i2all }; /* no terrorists here */

TIMAGE * scans[3] = { &i0, &i1, &i2 };

TIMAGE   * dummyScanner ( void )
 {
   static int idx = 0;

   if ( idx < 3 ) return ( scans[idx ++] );
   return ( NULL );
 }

void       dummyOfficer  ( TIMAGE * img, int found )
 {
   int i;

   printf ( "Image: %d x %d  ", img -> m_W, img -> m_H );
   if ( found )
    {
      printf ( "TERRORISTS:" );
      for ( i = 0; i < (int)sizeof ( found ) * 8; i ++ )
       if ( found & ( 1 << i ) )
        printf ( " %d", i );
      printf ( "\n" );
    }
   else
    printf ( "no terrorists found\n" );
 }

int main ( int argc, char * argv[] )
 {
   TerroristHunter ( 2, terrorists, 20, dummyScanner, dummyOfficer );
   return ( 0 );
 }
#endif /* __PROGTEST__ */

Answer 1

饥饿不是问题，因为当 scanner() 返回 NULL 时，线程将结束。

因此在我看来，问题出在何时定义了 PROGTEST。换句话说，你程序的其他地方有问题，这里没有列出；可能使用 scanner() 和/或 officer() 函数。