信号的漏桶实现

1、一段时间内打印固定数据

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <stdbool.h>
#include <errno.h>
#include <fcntl.h>
#define SPEED    1024
#define BUFFSIZE  SPEEDvolatile static bool loop = false;
#define ALARM   3
static void alrm_handler(int signo)
{alarm(3);loop = true;
}int main( int argc, char** argv)
{if( argc < 2){fprintf(stderr,"Usage:%s <src_file> \n",argv[0]);exit(0);}int sfd,dfd = 1;char buff[BUFFSIZE];if( (sfd = open(argv[1],O_RDONLY))<0){perror("open()");exit(1);}signal(SIGALRM,alrm_handler);    alarm(3);while(1){while(!loop)pause();loop = false;ssize_t read_size;errno =0;while((read_size =  read(sfd,buff,BUFFSIZE)) < 0){if( errno == EINTR){errno = 0;continue;}}//      read_size =  read(sfd,buff,BUFFSIZE);if( read_size == 0)break;if( read_size < 0)break;ssize_t write_size = 0;errno = 0;while( read_size){ssize_t ret = write(dfd,buff+write_size,read_size);if( ret < 0 && errno != EINTR){break;}errno =0;read_size -= ret;}}close(sfd);exit(0);}

2、 实现令牌桶

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <stdbool.h>
#include <errno.h>
#include <fcntl.h>
#define SPEED    1024
#define BUFFSIZE  SPEED
#define  BURST   100
volatile static bool loop = false;
#define ALARM   1
volatile static int token =0;
static void alrm_handler(int signo)
{alarm(ALARM);//   loop = true;token ++;if( token > BURST)token = BURST;
}int main( int argc, char** argv)
{if( argc < 2){fprintf(stderr,"Usage:%s <src_file> \n",argv[0]);exit(0);}int sfd,dfd = 1;char buff[BUFFSIZE];if( (sfd = open(argv[1],O_RDONLY))<0){perror("open()");exit(1);}signal(SIGALRM,alrm_handler);    alarm(3);while(1){while(token <=0)pause();token--;//loop = false;ssize_t read_size;errno =0;while((read_size =  read(sfd,buff,BUFFSIZE)) < 0){if( errno == EINTR){errno = 0;continue;}}//      read_size =  read(sfd,buff,BUFFSIZE);if( read_size == 0)break;if( read_size < 0)break;ssize_t write_size = 0;errno = 0;while( read_size){ssize_t ret = write(dfd,buff+write_size,read_size);if( ret < 0 && errno != EINTR){break;}errno =0;read_size -= ret;}}close(sfd);exit(0);}