C++ strptime实现
来源：互联网 发布：易语言获取网页源码 编辑：程序博客网 时间：2024/06/04 19:47
strptime.h
#pragma once#include "stdafx.h"#include <ctype.h>#include <string.h>#include <time.h> /* * We do not implement alternate representations. However, we always * check whether a given modifier is allowed for a certain conversion. */#define ALT_E 0x01#define ALT_O 0x02//#define LEGAL_ALT(x) { if (alt_format & ~(x)) return (0); }#define LEGAL_ALT(x) { ; }#define TM_YEAR_BASE (1970) static int conv_num(const char **, int *, int, int);static int strncasecmp(char *s1, char *s2, size_t n); static const char *day[7] = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};static const char *abday[7] = { "Sun","Mon","Tue","Wed","Thu","Fri","Sat"};static const char *mon[12] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"};static const char *abmon[12] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};static const char *am_pm[2] = { "AM", "PM"};char * strptime(const char *buf, const char *fmt, struct tm *tm);static intconv_num(const char **buf, int *dest, int llim, int ulim);int strncasecmp(char *s1, char *s2, size_t n);strptime.cpp
#include "stdafx.h"#include "strptime.h" char *strptime(const char *buf, const char *fmt, struct tm *tm){ char c; const char *bp; size_t len = 0; int alt_format, i, split_year = 0; bp = buf; while ((c = *fmt) != '/0') { /* Clear `alternate' modifier prior to new conversion. */ alt_format = 0; /* Eat up white-space. */ if (isspace(c)) { while (isspace(*bp)) bp++; fmt++; continue; } if ((c = *fmt++) != '%') goto literal; again: switch (c = *fmt++) { case '%': /* "%%" is converted to "%". */literal: if (c != *bp++) return (0); break; /* * "Alternative" modifiers. Just set the appropriate flag * and start over again. */ case 'E': /* "%E?" alternative conversion modifier. */ LEGAL_ALT(0); alt_format |= ALT_E; goto again; case 'O': /* "%O?" alternative conversion modifier. */ LEGAL_ALT(0); alt_format |= ALT_O; goto again; /* * "Complex" conversion rules, implemented through recursion. */ case 'c': /* Date and time, using the locale's format. */ LEGAL_ALT(ALT_E); if (!(bp = strptime(bp, "%x %X", tm))) return (0); break; case 'D': /* The date as "%m/%d/%y". */ LEGAL_ALT(0); if (!(bp = strptime(bp, "%m/%d/%y", tm))) return (0); break; case 'R': /* The time as "%H:%M". */ LEGAL_ALT(0); if (!(bp = strptime(bp, "%H:%M", tm))) return (0); break; case 'r': /* The time in 12-hour clock representation. */ LEGAL_ALT(0); if (!(bp = strptime(bp, "%I:%M:%S %p", tm))) return (0); break; case 'T': /* The time as "%H:%M:%S". */ LEGAL_ALT(0); if (!(bp = strptime(bp, "%H:%M:%S", tm))) return (0); break; case 'X': /* The time, using the locale's format. */ LEGAL_ALT(ALT_E); if (!(bp = strptime(bp, "%H:%M:%S", tm))) return (0); break; case 'x': /* The date, using the locale's format. */ LEGAL_ALT(ALT_E); if (!(bp = strptime(bp, "%m/%d/%y", tm))) return (0); break; /* * "Elementary" conversion rules. */ case 'A': /* The day of week, using the locale's form. */ case 'a': LEGAL_ALT(0); for (i = 0; i < 7; i++) { /* Full name. */ len = strlen(day[i]); if (strncasecmp((char *)(day[i]), (char *)bp, len) == 0) break; /* Abbreviated name. */ len = strlen(abday[i]); if (strncasecmp((char *)(abday[i]), (char *)bp, len) == 0) break; } /* Nothing matched. */ if (i == 7) return (0); tm->tm_wday = i; bp += len; break; case 'B': /* The month, using the locale's form. */ case 'b': case 'h': LEGAL_ALT(0); for (i = 0; i < 12; i++) { /* Full name. */ len = strlen(mon[i]); if (strncasecmp((char *)(mon[i]), (char *)bp, len) == 0) break; /* Abbreviated name. */ len = strlen(abmon[i]); if (strncasecmp((char *)(abmon[i]),(char *) bp, len) == 0) break; } /* Nothing matched. */ if (i == 12) return (0); tm->tm_mon = i; bp += len; break; case 'C': /* The century number. */ LEGAL_ALT(ALT_E); if (!(conv_num(&bp, &i, 0, 99))) return (0); if (split_year) { tm->tm_year = (tm->tm_year % 100) + (i * 100); } else { tm->tm_year = i * 100; split_year = 1; } break; case 'd': /* The day of month. */ case 'e': LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &tm->tm_mday, 1, 31))) return (0); break; case 'k': /* The hour (24-hour clock representation). */ LEGAL_ALT(0); /* FALLTHROUGH */ case 'H': LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &tm->tm_hour, 0, 23))) return (0); break; case 'l': /* The hour (12-hour clock representation). */ LEGAL_ALT(0); /* FALLTHROUGH */ case 'I': LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &tm->tm_hour, 1, 12))) return (0); if (tm->tm_hour == 12) tm->tm_hour = 0; break; case 'j': /* The day of year. */ LEGAL_ALT(0); if (!(conv_num(&bp, &i, 1, 366))) return (0); tm->tm_yday = i - 1; break; case 'M': /* The minute. */ LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &tm->tm_min, 0, 59))) return (0); break; case 'm': /* The month. */ LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &i, 1, 12))) return (0); tm->tm_mon = i - 1; break; // case 'p': /* The locale's equivalent of AM/PM. */// LEGAL_ALT(0);// /* AM? */// if (strcasecmp(am_pm[0], bp) == 0) {// if (tm->tm_hour > 11)// return (0);//// bp += strlen(am_pm[0]);// break;// }// /* PM? */// else if (strcasecmp(am_pm[1], bp) == 0) {// if (tm->tm_hour > 11)// return (0);//// tm->tm_hour += 12;// bp += strlen(am_pm[1]);// break;// }//// /* Nothing matched. */// return (0); case 'S': /* The seconds. */ LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &tm->tm_sec, 0, 61))) return (0); break; case 'U': /* The week of year, beginning on sunday. */ case 'W': /* The week of year, beginning on monday. */ LEGAL_ALT(ALT_O); /* * XXX This is bogus, as we can not assume any valid * information present in the tm structure at this * point to calculate a real value, so just check the * range for now. */ if (!(conv_num(&bp, &i, 0, 53))) return (0); break; case 'w': /* The day of week, beginning on sunday. */ LEGAL_ALT(ALT_O); if (!(conv_num(&bp, &tm->tm_wday, 0, 6))) return (0); break; case 'Y': /* The year. */ LEGAL_ALT(ALT_E); if (!(conv_num(&bp, &i, 0, 9999))) return (0); tm->tm_year = i - TM_YEAR_BASE; break; case 'y': /* The year within 100 years of the epoch. */ LEGAL_ALT(ALT_E | ALT_O); if (!(conv_num(&bp, &i, 0, 99))) return (0); if (split_year) { tm->tm_year = ((tm->tm_year / 100) * 100) + i; break; } split_year = 1; if (i <= 68) tm->tm_year = i + 2000 - TM_YEAR_BASE; else tm->tm_year = i + 1900 - TM_YEAR_BASE; break; /* * Miscellaneous conversions. */ case 'n': /* Any kind of white-space. */ case 't': LEGAL_ALT(0); while (isspace(*bp)) bp++; break; default: /* Unknown/unsupported conversion. */ return (0); } } /* LINTED functional specification */ return ((char *)bp);} static intconv_num(const char **buf, int *dest, int llim, int ulim){ int result = 0; /* The limit also determines the number of valid digits. */ int rulim = ulim; if (**buf < '0' || **buf > '9') return (0); do { result *= 10; result += *(*buf)++ - '0'; rulim /= 10; } while ((result * 10 <= ulim) && rulim && **buf >= '0' && **buf <= '9'); if (result < llim || result > ulim) return (0); *dest = result; return (1);} int strncasecmp(char *s1, char *s2, size_t n){ if (n == 0) return 0; while (n-- != 0 && tolower(*s1) == tolower(*s2)) { if (n == 0 || *s1 == '/0' || *s2 == '/0') break; s1++; s2++; } return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);} 调用:
struct tm atTime;
char fmt[] = "%Y-%m-%d %H:%M:%S";
strptime("2012-12-20 20:00:00",fmt,&atTM);
- strptime windows实现
- C++ strptime实现
- C\C++ windows 绕过strptime
- c语言之date_format日期格式化和strptime函数windows平台上实现
- strftime，strptime系统函数
- strftime和strptime使用
- strftime和strptime使用
- strptime的威力
- python 时间差 datetime strptime
- Python time strptime()方法
- "undefined reference to strptime"之自定义strptime函数
- Python:time, strftime和strptime
- linux时间函数描述-strptime
- Python:time, strftime和strptime
- Python中time.strptime支持的timezone
- hp unix下strptime的使用
- strptime与strftime函数的使用
- strftime、strptime和stime的使用
- 如何单独编译Android源代码中的模块
- hdu 2708 Vertical Histogram
- 搭建云计算环境：CentOS+XEN+Eucalyptus
- Base64解密
- MFC的数组类：CArray,CByteArray,CWordArray,CDWordArray
- C++ strptime实现
- linux C经典面试题五
- hive UDF实现一个字符串解码函数
- poj 1088 滑雪问题
- hdu 1272 小希的迷宫
- google地图改版后 不使用帐号获取 key的方法 {已经 过时}
- Linux 多线程函数解析
- Android无法访问本地服务器（localhost）的解决方案
- 本次OA系统设计经验，休假前的总结
