mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-22 11:17:19 +00:00
357 lines
8.5 KiB
C
357 lines
8.5 KiB
C
/* $Id: msdosfs_conv.c,v 1.6 1995/10/29 15:31:46 phk Exp $ */
|
|
/* $NetBSD: msdosfs_conv.c,v 1.6.2.1 1994/08/30 02:27:57 cgd Exp $ */
|
|
|
|
/*
|
|
* Written by Paul Popelka (paulp@uts.amdahl.com)
|
|
*
|
|
* You can do anything you want with this software, just don't say you wrote
|
|
* it, and don't remove this notice.
|
|
*
|
|
* This software is provided "as is".
|
|
*
|
|
* The author supplies this software to be publicly redistributed on the
|
|
* understanding that the author is not responsible for the correct
|
|
* functioning of this software in any circumstances and is not liable for
|
|
* any damages caused by this software.
|
|
*
|
|
* October 1992
|
|
*/
|
|
|
|
/*
|
|
* System include files.
|
|
*/
|
|
#include <sys/param.h>
|
|
#include <sys/time.h>
|
|
#include <sys/kernel.h> /* defines tz */
|
|
#include <sys/systm.h> /* defines tz */
|
|
#include <machine/clock.h>
|
|
|
|
/*
|
|
* MSDOSFS include files.
|
|
*/
|
|
#include <msdosfs/direntry.h>
|
|
|
|
/*
|
|
* Total number of days that have passed for each month in a regular year.
|
|
*/
|
|
static u_short regyear[] = {
|
|
31, 59, 90, 120, 151, 181,
|
|
212, 243, 273, 304, 334, 365
|
|
};
|
|
|
|
/*
|
|
* Total number of days that have passed for each month in a leap year.
|
|
*/
|
|
static u_short leapyear[] = {
|
|
31, 60, 91, 121, 152, 182,
|
|
213, 244, 274, 305, 335, 366
|
|
};
|
|
|
|
/*
|
|
* Variables used to remember parts of the last time conversion. Maybe we
|
|
* can avoid a full conversion.
|
|
*/
|
|
u_long lasttime;
|
|
u_long lastday;
|
|
u_short lastddate;
|
|
u_short lastdtime;
|
|
|
|
/*
|
|
* Convert the unix version of time to dos's idea of time to be used in
|
|
* file timestamps. The passed in unix time is assumed to be in GMT.
|
|
*/
|
|
void
|
|
unix2dostime(tsp, ddp, dtp)
|
|
struct timespec *tsp;
|
|
u_short *ddp;
|
|
u_short *dtp;
|
|
{
|
|
u_long t;
|
|
u_long days;
|
|
u_long inc;
|
|
u_long year;
|
|
u_long month;
|
|
u_short *months;
|
|
|
|
/*
|
|
* If the time from the last conversion is the same as now, then
|
|
* skip the computations and use the saved result.
|
|
*/
|
|
t = tsp->ts_sec - (tz.tz_minuteswest * 60) - adjkerntz;
|
|
/* +- daylight savings time correction */ ;
|
|
if (lasttime != t) {
|
|
lasttime = t;
|
|
lastdtime = (((t % 60) >> 1) << DT_2SECONDS_SHIFT)
|
|
+ (((t / 60) % 60) << DT_MINUTES_SHIFT)
|
|
+ (((t / 3600) % 24) << DT_HOURS_SHIFT);
|
|
|
|
/*
|
|
* If the number of days since 1970 is the same as the last
|
|
* time we did the computation then skip all this leap year
|
|
* and month stuff.
|
|
*/
|
|
days = t / (24 * 60 * 60);
|
|
if (days != lastday) {
|
|
lastday = days;
|
|
for (year = 1970;; year++) {
|
|
inc = year & 0x03 ? 365 : 366;
|
|
if (days < inc)
|
|
break;
|
|
days -= inc;
|
|
}
|
|
months = year & 0x03 ? regyear : leapyear;
|
|
for (month = 0; days > months[month]; month++)
|
|
;
|
|
if (month > 0)
|
|
days -= months[month - 1];
|
|
lastddate = ((days + 1) << DD_DAY_SHIFT)
|
|
+ ((month + 1) << DD_MONTH_SHIFT);
|
|
/*
|
|
* Remember dos's idea of time is relative to 1980.
|
|
* unix's is relative to 1970. If somehow we get a
|
|
* time before 1980 then don't give totally crazy
|
|
* results.
|
|
*/
|
|
if (year > 1980)
|
|
lastddate += (year - 1980) << DD_YEAR_SHIFT;
|
|
}
|
|
}
|
|
*dtp = lastdtime;
|
|
*ddp = lastddate;
|
|
}
|
|
|
|
/*
|
|
* The number of seconds between Jan 1, 1970 and Jan 1, 1980. In that
|
|
* interval there were 8 regular years and 2 leap years.
|
|
*/
|
|
#define SECONDSTO1980 (((8 * 365) + (2 * 366)) * (24 * 60 * 60))
|
|
|
|
u_short lastdosdate;
|
|
u_long lastseconds;
|
|
|
|
/*
|
|
* Convert from dos' idea of time to unix'. This will probably only be
|
|
* called from the stat(), and fstat() system calls and so probably need
|
|
* not be too efficient.
|
|
*/
|
|
void
|
|
dos2unixtime(dd, dt, tsp)
|
|
u_short dd;
|
|
u_short dt;
|
|
struct timespec *tsp;
|
|
{
|
|
u_long seconds;
|
|
u_long month;
|
|
u_long year;
|
|
u_long days;
|
|
u_short *months;
|
|
|
|
seconds = (((dt & DT_2SECONDS_MASK) >> DT_2SECONDS_SHIFT) << 1)
|
|
+ ((dt & DT_MINUTES_MASK) >> DT_MINUTES_SHIFT) * 60
|
|
+ ((dt & DT_HOURS_MASK) >> DT_HOURS_SHIFT) * 3600;
|
|
/*
|
|
* If the year, month, and day from the last conversion are the
|
|
* same then use the saved value.
|
|
*/
|
|
if (lastdosdate != dd) {
|
|
lastdosdate = dd;
|
|
days = 0;
|
|
year = (dd & DD_YEAR_MASK) >> DD_YEAR_SHIFT;
|
|
days = year * 365;
|
|
days += year / 4 + 1; /* add in leap days */
|
|
if ((year & 0x03) == 0)
|
|
days--; /* if year is a leap year */
|
|
months = year & 0x03 ? regyear : leapyear;
|
|
month = (dd & DD_MONTH_MASK) >> DD_MONTH_SHIFT;
|
|
if (month < 1 || month > 12) {
|
|
printf(
|
|
"dos2unixtime(): month value out of range (%ld)\n",
|
|
month);
|
|
month = 1;
|
|
}
|
|
if (month > 1)
|
|
days += months[month - 2];
|
|
days += ((dd & DD_DAY_MASK) >> DD_DAY_SHIFT) - 1;
|
|
lastseconds = (days * 24 * 60 * 60) + SECONDSTO1980;
|
|
}
|
|
tsp->ts_sec = seconds + lastseconds + (tz.tz_minuteswest * 60)
|
|
+ adjkerntz /* -+ daylight savings time correction */ ;
|
|
tsp->ts_nsec = 0;
|
|
}
|
|
|
|
/*
|
|
* Cheezy macros to do case detection and conversion for the ascii
|
|
* character set. DOESN'T work for ebcdic.
|
|
*/
|
|
#define isupper(c) (c >= 'A' && c <= 'Z')
|
|
#define islower(c) (c >= 'a' && c <= 'z')
|
|
#define toupper(c) (c & ~' ')
|
|
#define tolower(c) (c | ' ')
|
|
|
|
/*
|
|
* DOS filenames are made of 2 parts, the name part and the extension part.
|
|
* The name part is 8 characters long and the extension part is 3
|
|
* characters long. They may contain trailing blanks if the name or
|
|
* extension are not long enough to fill their respective fields.
|
|
*/
|
|
|
|
/*
|
|
* Convert a DOS filename to a unix filename. And, return the number of
|
|
* characters in the resulting unix filename excluding the terminating
|
|
* null.
|
|
*/
|
|
int
|
|
dos2unixfn(dn, un)
|
|
u_char dn[11];
|
|
u_char *un;
|
|
{
|
|
int i;
|
|
int ni;
|
|
int ei;
|
|
int thislong = 0;
|
|
u_char c;
|
|
u_char *origun = un;
|
|
|
|
/*
|
|
* Find the last character in the name portion of the dos filename.
|
|
*/
|
|
for (ni = 7; ni >= 0; ni--)
|
|
if (dn[ni] != ' ')
|
|
break;
|
|
|
|
/*
|
|
* Find the last character in the extension portion of the
|
|
* filename.
|
|
*/
|
|
for (ei = 10; ei >= 8; ei--)
|
|
if (dn[ei] != ' ')
|
|
break;
|
|
|
|
/*
|
|
* Copy the name portion into the unix filename string. NOTE: DOS
|
|
* filenames are usually kept in upper case. To make it more unixy
|
|
* we convert all DOS filenames to lower case. Some may like this,
|
|
* some may not.
|
|
*/
|
|
for (i = 0; i <= ni; i++) {
|
|
c = dn[i];
|
|
*un++ = isupper(c) ? tolower(c) : c;
|
|
thislong++;
|
|
}
|
|
|
|
/*
|
|
* Now, if there is an extension then put in a period and copy in
|
|
* the extension.
|
|
*/
|
|
if (ei >= 8) {
|
|
*un++ = '.';
|
|
thislong++;
|
|
for (i = 8; i <= ei; i++) {
|
|
c = dn[i];
|
|
*un++ = isupper(c) ? tolower(c) : c;
|
|
thislong++;
|
|
}
|
|
}
|
|
*un++ = 0;
|
|
|
|
/*
|
|
* If first char of the filename is SLOT_E5 (0x05), then the real
|
|
* first char of the filename should be 0xe5. But, they couldn't
|
|
* just have a 0xe5 mean 0xe5 because that is used to mean a freed
|
|
* directory slot. Another dos quirk.
|
|
*/
|
|
if (*origun == SLOT_E5)
|
|
*origun = 0xe5;
|
|
|
|
return thislong;
|
|
}
|
|
|
|
/*
|
|
* Convert a unix filename to a DOS filename. This function does not ensure
|
|
* that valid characters for a dos filename are supplied.
|
|
*/
|
|
void
|
|
unix2dosfn(un, dn, unlen)
|
|
u_char *un;
|
|
u_char dn[11];
|
|
int unlen;
|
|
{
|
|
int i;
|
|
u_char c;
|
|
|
|
/*
|
|
* Fill the dos filename string with blanks. These are DOS's pad
|
|
* characters.
|
|
*/
|
|
for (i = 0; i <= 10; i++)
|
|
dn[i] = ' ';
|
|
|
|
/*
|
|
* The filenames "." and ".." are handled specially, since they
|
|
* don't follow dos filename rules.
|
|
*/
|
|
if (un[0] == '.' && unlen == 1) {
|
|
dn[0] = '.';
|
|
return;
|
|
}
|
|
if (un[0] == '.' && un[1] == '.' && unlen == 2) {
|
|
dn[0] = '.';
|
|
dn[1] = '.';
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Copy the unix filename into the dos filename string upto the end
|
|
* of string, a '.', or 8 characters. Whichever happens first stops
|
|
* us. This forms the name portion of the dos filename. Fold to
|
|
* upper case.
|
|
*/
|
|
for (i = 0; i <= 7 && unlen && (c = *un) && c != '.'; i++) {
|
|
dn[i] = islower(c) ? toupper(c) : c;
|
|
un++;
|
|
unlen--;
|
|
}
|
|
|
|
/*
|
|
* If the first char of the filename is 0xe5, then translate it to
|
|
* 0x05. This is because 0xe5 is the marker for a deleted
|
|
* directory slot. I guess this means you can't have filenames
|
|
* that start with 0x05. I suppose we should check for this and
|
|
* doing something about it.
|
|
*/
|
|
if (dn[0] == SLOT_DELETED)
|
|
dn[0] = SLOT_E5;
|
|
|
|
/*
|
|
* Strip any further characters up to a '.' or the end of the
|
|
* string.
|
|
*/
|
|
while (unlen && (c = *un)) {
|
|
un++;
|
|
unlen--;
|
|
/* Make sure we've skipped over the dot before stopping. */
|
|
if (c == '.')
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Copy in the extension part of the name, if any. Force to upper
|
|
* case. Note that the extension is allowed to contain '.'s.
|
|
* Filenames in this form are probably inaccessable under dos.
|
|
*/
|
|
for (i = 8; i <= 10 && unlen && (c = *un); i++) {
|
|
dn[i] = islower(c) ? toupper(c) : c;
|
|
un++;
|
|
unlen--;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Get rid of these macros before someone discovers we are using such
|
|
* hideous things.
|
|
*/
|
|
#undef isupper
|
|
#undef islower
|
|
#undef toupper
|
|
#undef tolower
|