strftime.c

vxworks libc库源代码

/* strftime.c - strftime file for time  */

/* Copyright 1991-1999 Wind River Systems, Inc. */

/*
modification history
--------------------
01l,05aug99,cno  atoi calls need byte for null termination (SPR28245)
01k,23jul00,jrp  SPR 27606 End of DST miscalculated.
01j,08jun99,map  fixed 12hr reporting (SPR# 7499)
01i,20jan97,dbt  modified comment concerning seconds (SPR #4436).
01h,04oct96,dbt  reworked the fix for SPR #7277.
01g,03oct96,dbt  use memcpy with 'strlen + 1' instead of 'strlen' (SPR #7277)
01f,27jun96,dbt  corrected __getDstInfo() (spr 2521)
	 	 Updated copyright.
01g,10feb95,rhp  internal doc tweak from ansiTime.c
01f,15sep94,rhp  fixed TIMEZONE example in comment (related to SPR #3490)
01e,17aug93,dvs  changed TIME to TIMEO to fix conflicting defines (SPR #2249)
01d,05feb93,jdi  documentation cleanup for 5.1.
01c,20sep92,smb  documentation additions
01b,26jul92,rrr  fixed decl of __weekOfYear to compile on mips.
01a,25jul92,smb  written.
*/

/*  
DESCRIPTION  
  
INCLUDE FILE: time.h, stdlib.h, string.h, locale.h
   
SEE ALSO: American National Standard X3.159-1989 

NOMANUAL
*/

#include "vxWorks.h"
#include "string.h"
#include "stdlib.h"
#include "locale.h"
#include "private/timeP.h"

extern TIMELOCALE * __loctime;		/* time locale information */

/* LOCAL */

LOCAL size_t strftime_r (char *, size_t, const char *,
			 const struct tm *, TIMELOCALE *);
LOCAL void   __generateTime (char *, const struct tm *,
		             TIMELOCALE *, int *, const char *);
LOCAL void   __getDay (char *, int, int, TIMELOCALE *, int *);
LOCAL void   __getMonth (char *, int, int, TIMELOCALE *, int *);
LOCAL void   __getLocale (char *, int, const struct tm *, TIMELOCALE *, int *);
LOCAL void   __intToStr (char *, int, int);
LOCAL int    __weekOfYear (int, int, int);


/*******************************************************************************
*
* strftime - convert broken-down time into a formatted string (ANSI)
*
* This routine formats the broken-down time in <tptr> based on the conversion
* specified in the string <format>, and places the result in the string <s>.
*
* The format is a multibyte character sequence, beginning and ending in its
* initial state.  The <format> string consists of zero or more conversion
* specifiers and ordinary multibyte characters.  A conversion specifier
* consists of a % character followed by a character that determines the
* behavior of the conversion.  All ordinary multibyte characters (including
* the terminating NULL character) are copied unchanged to the array.  If
* copying takes place between objects that overlap, the behavior is
* undefined.  No more than <n> characters are placed into the array.
*
* Each conversion specifier is replaced by appropriate characters as 
* described in the following list.  The appropriate characters are determined 
* by the LC_TIME category of the current locale and by the values contained 
* in the structure pointed to by <tptr>.
*
* .iP %a
* the locale's abbreviated weekday name.
* .iP %A
* the locale's full weekday name.
* .iP %b
* the locale's abbreviated month name.
* .iP %B
* the locale's full month name.
* .iP %c
* the locale's appropriate date and time representation.
* .iP %d
* the day of the month as decimal number (01-31).
* .iP %H
* the hour (24-hour clock) as a decimal number (00-23).
* .iP %I
* the hour (12-hour clock) as a decimal number (01-12).
* .iP %j
* the day of the year as decimal number (001-366).
* .iP %m
* the month as a decimal number (01-12).
* .iP %M
* the minute as a decimal number (00-59).
* .iP %P
* the locale's equivalent of the AM/PM 
* designations associated with a 12-hour clock.
* .iP %S
* the second as a decimal number (00-59).
* .iP %U
* the week number of the year (first Sunday
* as the first day of week 1) as a decimal number (00-53).
* .iP %w
* the weekday as a decimal number (0-6), where Sunday is 0.
* .iP %W
* the week number of the year (the first Monday
* as the first day of week 1) as a decimal number (00-53).
* .iP %x
* the locale's appropriate date representation.
* .iP %X
* the locale's appropriate time representation.
* .iP %y
* the year without century as a decimal number (00-99).
* .iP %Y
* the year with century as a decimal number.
* .iP %Z
* the time zone name or abbreviation, or by no
* characters if no time zone is determinable.
* .iP %%
* %.
* .LP
*
* For any other conversion specifier, the behavior is undefined.
*
* INCLUDE FILES: time.h
*
* RETURNS:
* The number of characters in <s>, not including the terminating null
* character -- or zero if the number of characters in <s>, including the null
* character, is more than <n> (in which case the contents of <s> are
* indeterminate).
*/

size_t strftime
    (
    char *            s,		/* string array */
    size_t            n,		/* maximum size of array */
    const char *      format,		/* format of output string */
    const struct tm * tptr		/* broken-down time */
    )
    {
    return (strftime_r (s, n, format, tptr, __loctime));
    }

/*******************************************************************************
*
* strftime_r - format time into a string (POSIX)
*
* Re-entrant version of strftime().
*
* RETURNS:
*/

LOCAL size_t strftime_r
    (
    char *            bufHd,		/* string array */
    size_t            bufMaxSz,		/* maximum size of array */
    const char *      fmtHd,		/* format of output string */
    const struct tm * tmptr, 		/* broken-down time */
    TIMELOCALE *      timeInfo		/* locale information */
    )
    {
    const char *      fmt = fmtHd;
    char *            buffer = bufHd;
    char              addOn[MaxBufferSize];
    int               bufLen = 0;
    int               bufszNow = 0;
    
    FOREVER
       	{
       	while ((*fmt != '%') && (bufszNow != bufMaxSz) && (*fmt != EOS))
	    {
    	    bufszNow++; 
	    *buffer++ = *fmt++;
	    }

       	if (bufszNow == bufMaxSz) 
	    break;

       	if (*fmt++ != EOS)
	    {
	    __generateTime (addOn, tmptr, timeInfo, &bufLen, fmt);
	    if (bufLen >= 0)
	        {
	        if (bufMaxSz > (bufszNow + bufLen))
	            {
	            memcpy (buffer, addOn, bufLen);
	 	    bufszNow += bufLen;
		    buffer += bufLen;
		    fmt++;
		    } /* endif */
	        else 
		    {
		    memcpy (buffer, addOn, bufMaxSz - bufszNow);
		    buffer += (bufMaxSz - bufszNow);
		    bufszNow = bufMaxSz;
		    break;
		    }
		}	
	    else 
	        { /* process format strings */
		*(addOn + abs (bufLen)) = EOS; 

		/* This is recursive - but should recurse ONCE only */
	        bufLen = (int) strftime_r (buffer, 
					   bufMaxSz - bufszNow, 
					   addOn, 
					   tmptr, 
					   timeInfo);
	        buffer += bufLen;
	        bufszNow += bufLen;
	        fmt++;
	        } /* endif */	
	     }
	 else break;
         } /* end forever */
    *buffer = EOS;
    return (bufszNow);
    }

/*******************************************************************************
*
* __generateTime - generate a string representing the format indicator.
*
* Internal routine
*
* RETURNS:
* NOMANUAL
*/

LOCAL void __generateTime
    (
    char *            addOn,	/* string buffer */
    const struct tm * tmptr, 	/* broken-down time */
    TIMELOCALE *      timeInfo,	/* locale information */
    int *             pnum,	/* position number for strftime string */
    const char *      fmt	/* format to be decoded */
    )
    {
    switch (*fmt) 
    	{
        case 'a':	/* day */
    	    __getDay (addOn, tmptr->tm_wday, ABBR, timeInfo, pnum); 
    	    break;
        case 'A':	/* day */
    	    __getDay (addOn, tmptr->tm_wday, FULL, timeInfo, pnum); 
    	    break;
        case 'b':	/* month */
    	    __getMonth (addOn, tmptr->tm_mon, ABBR, timeInfo, pnum); 
    	    break;
        case 'B':	/* month */
    	    __getMonth (addOn, tmptr->tm_mon, FULL, timeInfo, pnum);
    	    break;
        case 'c': 	/* date and time */
    	    __getLocale (addOn, DATETIME, tmptr, timeInfo, pnum);
    	    *pnum = -*pnum;
    	    break;
        case 'd': 	/* day of month */
    	    __intToStr (addOn, tmptr->tm_mday, *pnum = 2); 
    	    break;
        case 'H':	/* hour */
    	    __intToStr (addOn, tmptr->tm_hour, *pnum = 2); 
    	    break;
        case 'I':	/* hour */
            __intToStr (addOn, ((tmptr->tm_hour % 12) ?
                                (tmptr->tm_hour % 12) : 12), *pnum = 2);
    	    break;
        case 'j':	/* day of year */
    	    __intToStr (addOn, tmptr->tm_yday + 1, *pnum = 3); 
    	    break;
        case 'm':	/* month */
    	    __intToStr (addOn, tmptr->tm_mon + 1, *pnum = 2); 
    	    break;
        case 'M':	/* minute */
    	    __intToStr (addOn, tmptr->tm_min, *pnum = 2); 
    	    break;
        case 'p':	/* AP/PM */
    	    __getLocale (addOn, AMPM, tmptr, timeInfo, pnum);
    	    break;
        case 'S':	/* second */
    	    __intToStr (addOn, tmptr->tm_sec, *pnum = 2); 
       	    break;
        case 'U':	/* week number */
            __intToStr (addOn, 
			__weekOfYear(TM_SUNDAY, tmptr->tm_wday, tmptr->tm_yday),
			*pnum = 2);
    	    break;
        case 'w':	/* weekday */
    	    __intToStr (addOn, tmptr->tm_wday, *pnum = 1); 
    	    break;
        case 'W':	/* week number */
    	    __intToStr (addOn, 
    		        __weekOfYear(TM_MONDAY, tmptr->tm_wday, tmptr->tm_yday),
     	                *pnum = 2);
    	    break;
        case 'x':	/* date */
    	    __getLocale (addOn, DATE, tmptr, timeInfo, pnum);
    	    *pnum = -*pnum;
    	    break;
        case 'X':	/* time */
    	    __getLocale (addOn, TIMEO, tmptr, timeInfo, pnum);
       	    *pnum = -*pnum;
    	    break;
        case 'y':	/* year */
    	    __intToStr (addOn, (tmptr->tm_year % CENTURY), *pnum = 2);
    	    break;
        case 'Y':	/* year */
    	    __intToStr (addOn, (tmptr->tm_year + TM_YEAR_BASE), *pnum = 4);
    	    break;
        case 'Z':	/* zone */
    	    __getLocale (addOn, ZONE, tmptr, timeInfo, pnum);
    	    break;
        case '%':	/* % */
    	    memcpy (addOn, CHAR_FROM_CONST ("%"), 1); 
	    *pnum = 1; 
    	    break;
        default:
    	    *pnum = 0;
    	    break;