src/dosfs/msdos_conv.c

0001 /**
0002  * @file
0003  *
0004  * @ingroup libfs_msdos MSDOS FileSystem
0005  *
0006  * @brief MDOS Date Conversion
0007  */
0008
0009 /*
0010  * Written by Paul Popelka (paulp@uts.amdahl.com)
0011  *
0012  * You can do anything you want with this software, just don't say you wrote
0013  * it, and don't remove this notice.
0014  *
0015  * This software is provided "as is".
0016  *
0017  * The author supplies this software to be publicly redistributed on the
0018  * understanding that the author is not responsible for the correct
0019  * functioning of this software in any circumstances and is not liable for
0020  * any damages caused by this software.
0021  *
0022  * Adaptation of NetBSD code for RTEMS by Victor V. Vengerov <vvv@oktet.ru>
0023  * $NetBSD: msdosfs_conv.c,v 1.10 1994/12/27 18:36:24 mycroft Exp $
0024  *
0025  * October 1992
0026  *
0027  * Modifications to support UTF-8 in the file system are
0028  * Copyright (c) 2013 embedded brains GmbH & Co. KG
0029  */
0030
0031 #ifdef HAVE_CONFIG_H
0032 #include "config.h"
0033 #endif
0034
0035 #include <ctype.h>
0036 #include <rtems.h>
0037 #include "msdos.h"
0038
0039 /* #define SECONDSPERDAY (24 * 60 * 60) */
0040 #define SECONDSPERDAY ((uint32_t) 86400)
0041
0042 #define UTF8_MAX_CHAR_SIZE    4
0043 #define UTF8_NULL             0x00
0044 #define UTF8_NULL_SIZE        1
0045 #define UTF8_BLANK            0x20
0046 #define UTF8_BLANK_SIZE       1
0047 #define UTF8_FULL_STOP        0x2e
0048 #define UTF8_FULL_STOP_SIZE   1
0049
0050 #define UTF16_MAX_CHAR_SIZE   4
0051 #define UTF16_NULL            CT_LE_W( 0x0000 )
0052 #define UTF16_NULL_SIZE       2
0053 #define UTF16_BLANK           CT_LE_W( 0x0020 )
0054 #define UTF16_BLANK_SIZE      2
0055 #define UTF16_FULL_STOP       CT_LE_W( 0x002e )
0056 #define UTF16_FULL_STOP_SIZE  2
0057
0058 /*
0059  * Days in each month in a regular year.
0060  */
0061 static uint16_t regyear[] = {
0062     31, 28, 31, 30, 31, 30,
0063     31, 31, 30, 31, 30, 31
0064 };
0065
0066 /*
0067  * Days in each month in a leap year.
0068  */
0069 static uint16_t leapyear[] = {
0070     31, 29, 31, 30, 31, 30,
0071     31, 31, 30, 31, 30, 31
0072 };
0073
0074 /*
0075  * Variables used to remember parts of the last time conversion.  Maybe we
0076  * can avoid a full conversion.
0077  */
0078 static uint32_t lasttime;
0079 static uint32_t lastday;
0080 static uint16_t lastddate;
0081 static uint16_t lastdtime;
0082
0083 /*
0084  * Convert the unix version of time to dos's idea of time to be used in
0085  * file timestamps. The passed in unix time is assumed to be in GMT.
0086  */
0087 void
0088 msdos_date_unix2dos(unsigned int t, uint16_t *ddp,
0089                     uint16_t *dtp)
0090 {
0091     uint32_t days;
0092     uint32_t inc;
0093     uint32_t year;
0094     uint32_t month;
0095     uint16_t *months;
0096
0097     /*
0098      * If the time from the last conversion is the same as now, then
0099      * skip the computations and use the saved result.
0100      */
0101     if (lasttime != t) {
0102         lasttime = t;
0103         lastdtime = (((t % 60) >> 1) << MSDOS_DT_2SECONDS_SHIFT)
0104             + (((t / 60) % 60) << MSDOS_DT_MINUTES_SHIFT)
0105             + (((t / 3600) % 24) << MSDOS_DT_HOURS_SHIFT);
0106
0107         /*
0108          * If the number of days since 1970 is the same as the last
0109          * time we did the computation then skip all this leap year
0110          * and month stuff.
0111          */
0112         days = t / (SECONDSPERDAY);
0113         if (days != lastday) {
0114             lastday = days;
0115             for (year = 1970;; year++) {
0116                 inc = year & 0x03 ? 365 : 366;
0117                 if (days < inc)
0118                     break;
0119                 days -= inc;
0120             }
0121             months = year & 0x03 ? regyear : leapyear;
0122             for (month = 0; month < 12; month++) {
0123                 if (days < months[month])
0124                     break;
0125                 days -= months[month];
0126             }
0127             lastddate = ((days + 1) << MSDOS_DD_DAY_SHIFT)
0128                 + ((month + 1) << MSDOS_DD_MONTH_SHIFT);
0129             /*
0130              * Remember dos's idea of time is relative to 1980.
0131              * unix's is relative to 1970.  If somehow we get a
0132              * time before 1980 then don't give totally crazy
0133              * results.
0134              */
0135             if (year > 1980)
0136                 lastddate += (year - 1980) <<
0137                              MSDOS_DD_YEAR_SHIFT;
0138         }
0139     }
0140     *dtp = lastdtime;
0141     *ddp = lastddate;
0142 }
0143
0144 /*
0145  * The number of days between Jan 1, 1970 and Jan 1, 1980. In that
0146  * interval there were 8 regular years and 2 leap years.
0147  */
0148 /* #define  DAYSTO1980  ((8 * 365) + (2 * 366)) */
0149 #define DAYSTO1980   ((uint32_t) 3652)
0150
0151 static uint16_t lastdosdate;
0152 static uint32_t lastseconds;
0153
0154 /*
0155  * Convert from dos' idea of time to unix'. This will probably only be
0156  * called from the stat(), and fstat() system calls and so probably need
0157  * not be too efficient.
0158  */
0159 unsigned int
0160 msdos_date_dos2unix(unsigned int dd, unsigned int dt)
0161 {
0162     uint32_t seconds;
0163     uint32_t m, month;
0164     uint32_t y, year;
0165     uint32_t days;
0166     uint16_t *months;
0167
0168     seconds = 2 * ((dt & MSDOS_DT_2SECONDS_MASK) >> MSDOS_DT_2SECONDS_SHIFT)
0169         + ((dt & MSDOS_DT_MINUTES_MASK) >> MSDOS_DT_MINUTES_SHIFT) * 60
0170         + ((dt & MSDOS_DT_HOURS_MASK) >> MSDOS_DT_HOURS_SHIFT) * 3600;
0171     /*
0172      * If the year, month, and day from the last conversion are the
0173      * same then use the saved value.
0174      */
0175     if (lastdosdate != dd) {
0176         lastdosdate = dd;
0177         days = 0;
0178         year = (dd & MSDOS_DD_YEAR_MASK) >> MSDOS_DD_YEAR_SHIFT;
0179         for (y = 0; y < year; y++)
0180             days += y & 0x03 ? 365 : 366;
0181         months = year & 0x03 ? regyear : leapyear;
0182         /*
0183          * Prevent going from 0 to 0xffffffff in the following
0184          * loop.
0185          */
0186         month = (dd & MSDOS_DD_MONTH_MASK) >> MSDOS_DD_MONTH_SHIFT;
0187         if (month == 0) {
0188             month = 1;
0189         }
0190         for (m = 0; m < month - 1; m++)
0191             days += months[m];
0192         days += ((dd & MSDOS_DD_DAY_MASK) >> MSDOS_DD_DAY_SHIFT) - 1;
0193         lastseconds = (days + DAYSTO1980) * SECONDSPERDAY;
0194     }
0195     return seconds + lastseconds;
0196 }
0197
0198
0199 static const uint8_t codepage_valid_char_map[] = {
0200     0,    0,    0,    0,    0,    0,    0,    0,    /* 00-07 */
0201     0,    0,    0,    0,    0,    0,    0,    0,    /* 08-0f */
0202     0,    0,    0,    0,    0,    0,    0,    0,    /* 10-17 */
0203     0,    0,    0,    0,    0,    0,    0,    0,    /* 18-1f */
0204     0x20, 0x21, 0,    0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */
0205     0x28, 0x29, 0,    0,    0,    0x2d,  0,    0,   /* 28-2f */
0206     0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */
0207     0x38, 0x39, 0,    0,    0,    0,    0,    0,    /* 38-3f */
0208     0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 40-47 */
0209     0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 48-4f */
0210     0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 50-57 */
0211     0x58, 0x59, 0x5a, 0,    0,    0,    0x5e, 0x5f, /* 58-5f */
0212     0x60, 0,    0,    0,    0,    0,    0,    0,    /* 60-67 */
0213     0,    0,    0,    0,    0,    0,    0,    0,    /* 68-6f */
0214     0,    0,    0,    0,    0,    0,    0,    0,    /* 70-77 */
0215     0,    0,    0,    0x7b, 0,    0x7d, 0x7e, 0,    /* 78-7f */
0216     0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 80-87 */
0217     0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 88-8f */
0218     0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 90-97 */
0219     0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 98-9f */
0220     0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* a0-a7 */
0221     0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* a8-af */
0222     0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* b0-b7 */
0223     0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* b8-bf */
0224     0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* c0-c7 */
0225     0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* c8-cf */
0226     0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* d0-d7 */
0227     0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, /* d8-df */
0228     0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* e0-e7 */
0229     0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* e8-ef */
0230     0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* f0-f7 */
0231     0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff  /* f8-ff */
0232 };
0233
0234 static uint16_t
0235 msdos_get_valid_utf16_filename_character (const uint16_t utf16_character)
0236 {
0237   uint16_t retval    = 0x0000;
0238   uint16_t char_num  = CF_LE_W( utf16_character );
0239
0240   if ( char_num <= 0x00ff ) {
0241     switch ( char_num )
0242     {
0243       case 0x002b: /* '+' */
0244       case 0x002c: /* ',' */
0245       case 0x002e: /* '.' */
0246       case 0x003b: /* ';' */
0247       case 0x003d: /* '=' */
0248       case 0x005b: /* '[' */
0249       case 0x005d: /* ']' */
0250       case 0x0061: /* 'a' */
0251       case 0x0062: /* 'b' */
0252       case 0x0063: /* 'c' */
0253       case 0x0064: /* 'd' */
0254       case 0x0065: /* 'e' */
0255       case 0x0066: /* 'f' */
0256       case 0x0067: /* 'g' */
0257       case 0x0068: /* 'h' */
0258       case 0x0069: /* 'i' */
0259       case 0x006a: /* 'j' */
0260       case 0x006b: /* 'k' */
0261       case 0x006c: /* 'l' */
0262       case 0x006d: /* 'm' */
0263       case 0x006e: /* 'n' */
0264       case 0x006f: /* 'o' */
0265       case 0x0070: /* 'p' */
0266       case 0x0071: /* 'q' */
0267       case 0x0072: /* 'r' */
0268       case 0x0073: /* 's' */
0269       case 0x0074: /* 't' */
0270       case 0x0075: /* 'u' */
0271       case 0x0076: /* 'v' */
0272       case 0x0077: /* 'w' */
0273       case 0x0078: /* 'x' */
0274       case 0x0079: /* 'y' */
0275       case 0x007a: /* 'z' */
0276         retval = char_num;
0277       break;
0278       default:
0279         retval = codepage_valid_char_map[char_num];
0280       break;
0281     }
0282   }
0283   else
0284     retval = char_num;
0285
0286   return CT_LE_W( retval );
0287 }
0288
0289 static char
0290 msdos_get_valid_codepage_filename_character (const uint8_t character)
0291 {
0292   char c = codepage_valid_char_map[character];
0293
0294   if (c == 0) {
0295     c = '_';
0296   }
0297
0298   return c;
0299 }
0300
0301 static ssize_t
0302 msdos_filename_process_dot_names (const uint8_t *src_name,
0303                                   const size_t   src_size,
0304                                   uint8_t       *dest_name,
0305                                   const size_t   dest_size)
0306 {
0307   ssize_t returned_size = 0;
0308   int     eno           = 0;
0309   /*
0310     * The filenames "." and ".." are handled specially, since they
0311     * don't follow dos filename rules.
0312     */
0313    if (    src_name[0] == UTF8_FULL_STOP
0314         && src_size    == UTF8_FULL_STOP_SIZE) {
0315      if (dest_size >= UTF8_FULL_STOP_SIZE) {
0316        dest_name[0]  = UTF8_FULL_STOP;
0317        returned_size = UTF8_FULL_STOP_SIZE;
0318      }
0319      else
0320        eno = ENAMETOOLONG;
0321    }
0322    else if (    eno           == 0
0323              && src_name[0]   == UTF8_FULL_STOP
0324              && src_name[1]   == UTF8_FULL_STOP
0325              && src_size      == ( 2 * UTF8_FULL_STOP_SIZE ) ) {
0326      if (dest_size >= 2 * UTF8_FULL_STOP_SIZE) {
0327        dest_name[0]  = UTF8_FULL_STOP;
0328        dest_name[1]  = UTF8_FULL_STOP;
0329        returned_size = 2 * UTF8_FULL_STOP_SIZE;
0330      }
0331      else
0332        eno = ENAMETOOLONG;
0333    }
0334
0335    if (eno != 0) {
0336      errno         = eno;
0337      returned_size = -1;
0338    }
0339
0340    return returned_size;
0341 }
0342
0343 static ssize_t
0344 msdos_filename_delete_trailing_dots (const uint8_t *filename_utf8,
0345                                      const size_t   filename_size)
0346 {
0347   ssize_t      size_returned = filename_size;
0348   unsigned int i;
0349
0350   /*
0351    * Remove any dots from the end of a file name.
0352    */
0353   for ( i = size_returned - UTF8_FULL_STOP_SIZE;
0354            size_returned >= UTF8_FULL_STOP_SIZE
0355         && filename_utf8[i] == UTF8_FULL_STOP;) {
0356     size_returned -= UTF8_FULL_STOP_SIZE;
0357     i             -= UTF8_FULL_STOP_SIZE;
0358   }
0359
0360   return size_returned;
0361 }
0362
0363 ssize_t
0364 msdos_filename_utf8_to_long_name_for_compare (
0365     rtems_dosfs_convert_control     *converter,
0366     const uint8_t                   *utf8_name,
0367     const size_t                     utf8_name_size,
0368     uint8_t                         *long_name,
0369     const size_t                     long_name_size)
0370   {
0371     ssize_t        returned_size = 0;
0372     int            eno           = 0;
0373     size_t         name_size;
0374     size_t         dest_size     = long_name_size;
0375
0376     returned_size = msdos_filename_process_dot_names (
0377       utf8_name,
0378       utf8_name_size,
0379       long_name,
0380       long_name_size);
0381
0382     if (returned_size == 0) {
0383       name_size = msdos_filename_delete_trailing_dots (
0384         &utf8_name[0],
0385         utf8_name_size);
0386       if (name_size > 0) {
0387         eno = (*converter->handler->utf8_normalize_and_fold) (
0388           converter,
0389           utf8_name,
0390           name_size,
0391           long_name,
0392           &dest_size);
0393         if (eno == 0) {
0394           returned_size = (ssize_t)dest_size;
0395         }
0396       } else {
0397         eno = EINVAL;
0398       }
0399     }
0400
0401     if ( eno != 0 ) {
0402       errno         = eno;
0403       returned_size = -1;
0404     }
0405
0406     return returned_size;
0407   }
0408
0409 ssize_t
0410 msdos_filename_utf8_to_long_name_for_save (
0411     rtems_dosfs_convert_control     *converter,
0412     const uint8_t                   *utf8_name,
0413     const size_t                     utf8_name_size,
0414     uint16_t                        *long_name,
0415     const size_t                     long_name_size)
0416 {
0417     ssize_t      returned_size = 0;
0418     int          eno           = 0;
0419     size_t       name_size;
0420     size_t       name_size_tmp;
0421     int          i;
0422     uint16_t     c;
0423     unsigned int chars_written;
0424
0425     name_size_tmp = long_name_size;
0426     name_size = msdos_filename_delete_trailing_dots (
0427       &utf8_name[0],
0428       utf8_name_size);
0429     if (name_size > 0) {
0430       /*
0431        * Finally convert from UTF-8 to UTF-16
0432        */
0433       eno = (*converter->handler->utf8_to_utf16) (
0434           converter,
0435           utf8_name,
0436           name_size,
0437           &long_name[0],
0438           &name_size_tmp);
0439       if (eno == 0) {
0440         if (name_size_tmp <= (MSDOS_NAME_MAX_LNF_LEN * MSDOS_NAME_LFN_BYTES_PER_CHAR))
0441           name_size = name_size_tmp;
0442         else
0443           eno = ENAMETOOLONG;
0444       }
0445
0446       if ( eno == 0 )
0447       {
0448         /*
0449          * Validate the characters and assign them to the UTF-16 file name
0450          */
0451         for ( i = 0;
0452                  name_size
0453               && (c = msdos_get_valid_utf16_filename_character ( long_name[i]) );
0454               ++i ) {
0455           long_name[i]   = c;
0456           returned_size += MSDOS_NAME_LFN_BYTES_PER_CHAR;
0457           name_size     -= MSDOS_NAME_LFN_BYTES_PER_CHAR;
0458         }
0459         if ( name_size == UTF16_NULL_SIZE && c == UTF16_NULL ) {
0460           long_name[i]   = c;
0461           returned_size += MSDOS_NAME_LFN_BYTES_PER_CHAR;
0462         }
0463         else if ( name_size != 0 )
0464           eno = EINVAL;
0465         chars_written = returned_size / MSDOS_NAME_LFN_BYTES_PER_CHAR;
0466         if (   long_name [chars_written - 1] != UTF16_NULL
0467             && (returned_size + UTF16_NULL_SIZE ) <= long_name_size ) {
0468           long_name[chars_written] = UTF16_NULL;
0469         }
0470       }
0471     }
0472     else
0473       eno = EINVAL;
0474
0475     if ( eno != 0 ) {
0476       errno         = eno;
0477       returned_size = -1;
0478     }
0479
0480     return returned_size;
0481   }
0482
0483 /*
0484  * Remove any dots from the start of a file name.
0485  */
0486 static void msdos_filename_remove_prepended_dots (const uint8_t **name_utf8,
0487                                                   size_t         *name_size)
0488 {
0489   while (    *name_size >= UTF8_FULL_STOP_SIZE
0490          && **name_utf8 == UTF8_FULL_STOP) {
0491     *name_utf8  += UTF8_FULL_STOP_SIZE;
0492     *name_size  -= UTF8_FULL_STOP_SIZE;
0493   }
0494 }
0495
0496 ssize_t
0497 msdos_filename_utf8_to_short_name_for_compare (
0498     rtems_dosfs_convert_control     *converter,
0499     const uint8_t                   *utf8_name,
0500     const size_t                     utf8_name_size,
0501     void                            *short_name,
0502     const size_t                     short_name_size)
0503 {
0504   ssize_t        returned_size           = 0;
0505   int            eno                     = 0;
0506   const uint8_t *name_ptr                = utf8_name;
0507   char          *dest_ptr                = (char*)short_name;
0508   size_t         name_size               = utf8_name_size;
0509   uint8_t        name_normalized_buf[(MSDOS_SHORT_NAME_LEN +1) * MSDOS_NAME_MAX_UTF8_BYTES_PER_CHAR];
0510   size_t         name_size_tmp           = sizeof(name_normalized_buf);
0511
0512   returned_size = msdos_filename_process_dot_names (
0513     utf8_name,
0514     utf8_name_size,
0515     short_name,
0516     short_name_size);
0517
0518   if (returned_size == 0) {
0519     msdos_filename_remove_prepended_dots (&name_ptr,
0520                                           &name_size);
0521     if (name_size > 0) {
0522       /*
0523        * Normalize the name and convert to lower case
0524        */
0525       eno = (*converter->handler->utf8_normalize_and_fold) (
0526         converter,
0527         name_ptr,
0528         name_size,
0529         &name_normalized_buf[0],
0530         &name_size_tmp);
0531       name_ptr  = &name_normalized_buf[0];
0532       name_size = name_size_tmp;
0533       if ( eno == ENOMEM ) {
0534         eno = 0;
0535       }
0536       if ( eno == 0 ) {
0537         memcpy (&dest_ptr[0], &name_ptr[0], name_size);
0538         returned_size = name_size;
0539       }
0540     } else
0541       eno = EINVAL;
0542   }
0543
0544   if ( eno != 0 ) {
0545     errno         = eno;
0546     returned_size = -1;
0547   }
0548
0549   return returned_size;
0550 }
0551
0552 ssize_t
0553 msdos_filename_utf8_to_short_name_for_save (
0554     rtems_dosfs_convert_control     *converter,
0555     const uint8_t                   *utf8_name,
0556     const size_t                     utf8_name_size,
0557     void                            *short_name,
0558     const size_t                     short_name_size)
0559 {
0560   ssize_t        returned_size           = 0;
0561   int            eno                     = 0;
0562   const uint8_t *name_ptr                = utf8_name;
0563   size_t         name_size               = utf8_name_size;
0564   char          *dest_ptr                = (char*)short_name;
0565   unsigned int   i;
0566   size_t         name_size_tmp;
0567   char           name_to_format_buf[MSDOS_SHORT_NAME_LEN +1];
0568
0569   returned_size = msdos_filename_process_dot_names (
0570     utf8_name,
0571     utf8_name_size,
0572     short_name,
0573     short_name_size);
0574
0575   if (returned_size == 0) {
0576     msdos_filename_remove_prepended_dots (&name_ptr,
0577                                           &name_size);
0578
0579     if (name_size > 0) {
0580       /*
0581        * Finally convert from UTF-8 to codepage
0582        */
0583       name_size_tmp = sizeof ( name_to_format_buf );
0584       eno = (*converter->handler->utf8_to_codepage) (
0585         converter,
0586         name_ptr,
0587         name_size,
0588         &name_to_format_buf[0],
0589         &name_size_tmp);
0590       if ( eno != 0 ) {
0591         /* The UTF-8 name my well be long name, for which we now want to
0592          * generate the corresponding short name. Under these circumstances
0593          * eno != 0 likely simply means that the UTF-8 name is longer than 11 characters
0594          * or that it contains unicode characters which can not be converted to the code page
0595          * in a reversible way. Non-reversible characters will be represented by question mark
0596          * characters. Later in this method they will get replaced by underline characters.
0597          */
0598         eno = 0;
0599       }
0600       name_ptr  = (const uint8_t *)(&name_to_format_buf[0]);
0601       name_size = name_size_tmp;
0602       for (i = 0; i < name_size; ++i)
0603         name_to_format_buf[i] = toupper ( (unsigned char)(name_to_format_buf[i]) );
0604       /*
0605        * Validate the characters and assign them to the codepage file name
0606        */
0607       if ( name_size > 0 ) {
0608         /*
0609          * The first character needs some special treatment
0610          */
0611         if ( 0x20 == *name_ptr )
0612           dest_ptr[0] = '_';
0613         else if ( 0xE5 == *name_ptr )
0614           dest_ptr[0] = 0x05;
0615         else
0616           dest_ptr[0] = msdos_get_valid_codepage_filename_character(*name_ptr);
0617         ++name_ptr;
0618         ++returned_size;
0619         --name_size;
0620         /*
0621          * Validate and assign all other characters of the name part
0622          */
0623         for (i = 1; i <= 7 && name_size && *name_ptr != '.'; ++i) {
0624           dest_ptr[i] = msdos_get_valid_codepage_filename_character(*name_ptr);
0625           ++name_ptr;
0626           ++returned_size;
0627           --name_size;
0628         }
0629         /*
0630          * Strip any further characters up to a '.' or the end of the
0631          * string.
0632          */
0633         if ( name_size > 0 && *name_ptr == '.' ) {
0634           ++name_ptr;
0635           --name_size;
0636         }
0637
0638         for (; i < 8; ++i) {
0639           dest_ptr[i] = ' ';
0640           ++returned_size;
0641         }
0642
0643         /*
0644          * Copy in the extension part of the name, if any.
0645          */
0646         for (; i <= 10 && name_size ; i++) {
0647           dest_ptr[i] = msdos_get_valid_codepage_filename_character(*name_ptr);
0648           ++name_ptr;
0649           ++returned_size;
0650           name_size--;
0651         }
0652         /*
0653          * Fill up with blanks. These are DOS's pad characters.
0654          */
0655         for ( ; i < short_name_size; ++i ) {
0656           dest_ptr[i] = ' ';
0657           ++returned_size;
0658         }
0659       }
0660     }
0661     else
0662       eno = EINVAL;
0663   }
0664
0665   if ( eno != 0 ) {
0666     errno = eno;
0667     return -1;
0668   }
0669
0670   return returned_size;
0671 }
0672
0673