C语言实现了crontab表达式执行时间

/* 作者：李猿 联系方式：QQ -- 2573507779 测试方法： */ #include "stdlib.h" #include "string.h" #include "stdio.h" typedef unsigned char uint8_t; typedef unsigned short int uint16_t; typedef unsigned int uint32_t; #define DEBUG_LINE() printf("FUN:%s LINE:%d TIME:%s\r\n", __FUNCTION__, __LINE__, __TIME__)// //时间 的临时变量，以计算下次唤醒的时间节点 struct data_time_str { //uint8_t sec; uint8_t min; uint8_t hour; uint8_t day; uint8_t month; uint16_t year; uint8_t week; }; static const char *const DowAry[] = { "sun", "mon", "tue", "wed", "thu", "fri", "sat", "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", NULL }; static const char *const MonAry[] = { "jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec", "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", NULL }; typedef struct CronLine { char cl_Mins[60]; /* 0-59 */ char cl_Hrs[24]; /* 0-23 */ char cl_Days[32]; /* 0-31 */ char cl_Mons[12]; /* 0-11 */ char cl_Dow[7]; /* 0-6, beginning sunday */ } CronLine; static char *ParseField(char *user, char *ary, int modvalue, int off, const char *const *names, char *ptr) { char *base = ptr; int n1 = -1; int n2 = -1; if (base == NULL) { return (NULL); } while (*ptr != ' ' && *ptr != '\t' && *ptr != '\n') { int skip = 0; /* Handle numeric digit or symbol or '*' */ if (*ptr == '*') { n1 = 0; /* everything will be filled */ n2 = modvalue - 1; skip = 1; ++ptr; } else if (*ptr >= '0' && *ptr <= '9') { if (n1 < 0) { n1 = strtol(ptr, &ptr, 10) + off; } else { n2 = strtol(ptr, &ptr, 10) + off; } skip = 1; } else if (names) { int i; for (i = 0; names[i]; ++i) { if (strncmp(ptr, names[i], strlen(names[i])) == 0) { break; } } if (names[i]) { ptr += strlen(names[i]); if (n1 < 0) { n1 = i; } else { n2 = i; } skip = 1; } } /* handle optional range '-' */ if (skip == 0) { printf(" failed user %s parsing %s\n", user, base); DEBUG_LINE(); return (NULL); } if (*ptr == '-' && n2 < 0) { ++ptr; continue; } /* * collapse single-value ranges, handle skipmark, and fill * in the character array appropriately. */ if (n2 < 0) { n2 = n1; } if (*ptr == '/') { skip = strtol(ptr + 1, &ptr, 10); } /* * fill array, using a failsafe is the easiest way to prevent * an endless loop */ { int s0 = 1; int failsafe = 1024; --n1; do { n1 = (n1 + 1) % modvalue; if (--s0 == 0) { ary[n1 % modvalue] = 1; s0 = skip; } } while (n1 != n2 && --failsafe); if (failsafe == 0) { printf(" failed user %s parsing %s\n", user, base); DEBUG_LINE(); return (NULL); } } if (*ptr != ',') { break; } ++ptr; n1 = -1; n2 = -1; } if (*ptr != ' ' && *ptr != '\t' && *ptr != '\n') { printf(" failed user %s parsing %s\n", user, base); DEBUG_LINE(); return (NULL); } while (*ptr == ' ' || *ptr == '\t' || *ptr == '\n') { ++ptr; } if (1) { int i; printf("%s:",user); for (i = 0; i < modvalue; ++i) { printf(" %d ", ary[i]); } printf("\r\n"); } return (ptr); } uint8_t GetMaxday(struct data_time_str *p_data) { uint8_t maxday = 0; uint16_t year = p_data->year; switch(p_data->month) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: maxday = 31; // 1 3 5 7 8 10 12月份 break; case 2: if((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) { maxday = 29; // 2月份 闰年 } else { maxday = 28; // 2月份 平年 } break; default : maxday = 30; // 4 6 9 11 月份 break; } return maxday; } //基姆拉尔森计算公式 //y:2019 m:8 d:28 //返回为 0 -- 6，beginning sunday uint8_t RTCGetWeek(uint32_t y,uint8_t m,uint8_t d) { uint8_t week = 0; if(m==1||m==2) { m+=12; y--; } week=(d+2*m+3*(m+1)/5+y+y/4-y/100+y/400+1)%7; return week; } //调用一次，加1分钟 void UpdateTimeBuf(struct data_time_str *p_data) { uint8_t maxday = 0; /*if(p_data->sec == 59) { p_data->sec = 0;*/ if(p_data->min == 59) { p_data->min = 0; if(p_data->hour == 23) { p_data->hour = 0; maxday = GetMaxday(p_data); if(p_data->day == maxday) { p_data->day = 1; if(p_data->month == 12) { p_data->month = 1; p_data->year++; } else { p_data->month++; } } else { p_data->day++; } } else { p_data->hour++; } } else { p_data->min++; } /*} else { p_data->sec++; } */ //根据年月日计算出当天是星期几 p_data->week = RTCGetWeek(p_data->year,p_data->month,p_data->day); } //寻找满足crond条件的时间点 uint8_t GetWakeUpTimePoint(CronLine *pline,struct data_time_str *p_data) { if((pline->cl_Mins[p_data->min] == 1) && (pline->cl_Hrs[p_data->hour] == 1) && (pline->cl_Days[p_data->day] == 1) && (pline->cl_Mons[p_data->month] == 1) && (pline->cl_Dow[p_data->week] == 1)) { printf("%04d年%02d月%02d日 %02d:%02d:00 星期%d\r\n", p_data->year,p_data->month,p_data->day, p_data->hour,p_data->min,p_data->week); return 1; } return 0; } int main() { CronLine line = {0}; char *ptr; /*buf：Crontab表达式*/ char buf[] = "0 0 1,20 * * "; //0 18 * * * //10 5 */5 * * ptr = ParseField("Mins", line.cl_Mins, 60, 0, NULL, buf); ptr = ParseField("Hrs", line.cl_Hrs, 24, 0, NULL, ptr); ptr = ParseField("Days", line.cl_Days, 32, 0, NULL, ptr); ptr = ParseField("Mons", line.cl_Mons, 12, -1, MonAry, ptr); ptr = ParseField("Week", line.cl_Dow, 7, 0, DowAry, ptr); if (ptr == NULL) { printf("It's over\r\n"); } /* uint8_t min; uint8_t hour; uint8_t day; uint8_t month; uint16_t year; */ //先定义个时间初始值 //struct data_time_str CalcDataTime = {34,9,30,8,2019,4}; struct data_time_str CalcDataTime = {0}; CalcDataTime.year = 2019; CalcDataTime.month = 8; CalcDataTime.day = 30; CalcDataTime.hour = 9; CalcDataTime.min = 34; uint32_t cnt = 0; //做个循环限制 uint8_t getcnt = 0; //记录找到唤醒时间的次数 while((cnt < 0xFFFFFFFF) && (getcnt <= 10)) { cnt++; UpdateTimeBuf(&CalcDataTime); if(GetWakeUpTimePoint(&line,&CalcDataTime)) { getcnt++; } } system("pause"); return 0; }