用C语言实现的定时器库－－－库实现。

接上一篇。。。
用C语言实现的定时器库－－－库实现。 timer.c

#include "timer.h"
#include <stdlib.h>

static int timercount = 0;
static timer *alltimer = NULL;
static int nowpos = -1;
static const int increase = 10;

static timer_errors timer_error = timerOK;

static const char *error_msg[] = 
    ...{
        "timer is ok.",
        "no such timer, please check it.",
        "initlize timer fail, beacuse of not enough memory.",
        "a avoid distm_second, it should be a postive float.",
        "no such error message"
    };


timerID initlize_timer(float distm)
...{
    timer *tmp;
    timer newtimer;
    
    if(distm < 0)
    ...{
        timer_error = timerAvoidDistm;
        return -1;
    }
    
    newtimer = (timer)malloc( sizeof(mytimer) );
    if(newtimer == NULL)
    ...{
        timer_error = timerOutOfMem;
        return    -1;
    }
    
    
    newtimer->distm_second = distm;
    newtimer->base_tm = clock();
    
    nowpos++;
    if(nowpos >= timercount)
    ...{
        tmp = (timer *)realloc((void*)alltimer, (unsigned int)(timercount+increase));
        if(tmp == NULL)
        ...{
            timer_error = timerOutOfMem;
            free(newtimer);
            return    -1;
        }
        alltimer = tmp;
        timercount = timercount + increase;
    }
    
    alltimer[nowpos] = newtimer;
    timer_error = timerOK;
    
    return (timerID)nowpos;
    
}


int is_timer_over(timerID  id)
...{
    timer p;
    clock_t nowclock = clock();
    if(id < 0  || id > nowpos)
    ...{
        timer_error = timerBadID;
        return -1;
    }    

    p = alltimer[id];
    if( (nowclock - p->base_tm) > ((p->distm_second)*CLK_TCK) )
    ...{
        p->base_tm = nowclock;
        return 1;
    }
    else
        return 0;
}

void reset_timer(timerID id)
...{
    timer p;
    clock_t nowclock;
    if(id < 0  || id > nowpos)
    ...{
        timer_error = timerBadID;
        return;
    }
    p = alltimer[id];
    nowclock = clock();
    p->base_tm = nowclock;
    
}

float get_timer_distm(timerID id)
...{
    timer p;
    if(id < 0  || id > nowpos)
    ...{
        timer_error = timerBadID;
        return -1;
    }
    p = alltimer[id];
    return p->distm_second;
}


void set_timer_distm(timerID  id, float newdistm)
...{
    timer p;
    if(newdistm < 0)
    ...{
        timer_error = timerAvoidDistm;
        return;
    }
    
    if(id < 0  || id > nowpos)
    ...{
        timer_error = timerBadID;
        return;
    }
    
    p= alltimer[id];
    p->distm_second = newdistm;

}

timer_errors timer_result(void)
...{
    return timer_error;
}

char * timer_msg(timer_errors err)
...{
    if((int)err < 0 ||(int)err >3)
        err = timerNoSuchErrCode;
    return (char *)error_msg[(int)err];
}