diff options
Diffstat (limited to 'cpukit/libfs/src/dosfs/msdos_conv.c')
| -rw-r--r-- | cpukit/libfs/src/dosfs/msdos_conv.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/cpukit/libfs/src/dosfs/msdos_conv.c b/cpukit/libfs/src/dosfs/msdos_conv.c new file mode 100644 index 0000000000..95b25814db --- /dev/null +++ b/cpukit/libfs/src/dosfs/msdos_conv.c @@ -0,0 +1,317 @@ +/* + * Adaptation of NetBSD code for RTEMS by Victor V. Vengerov <vvv@oktet.ru> + */ +/* $NetBSD: msdosfs_conv.c,v 1.10 1994/12/27 18:36:24 mycroft 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 + */ + +#if HAVE_CONFIG_H +#include "config.h" +#endif + +#include <rtems.h> +#include "msdos.h" + +/* #define SECONDSPERDAY (24 * 60 * 60) */ +#define SECONDSPERDAY ((uint32_t) 86400) + +/* + * Days in each month in a regular year. + */ +static uint16_t regyear[] = { + 31, 28, 31, 30, 31, 30, + 31, 31, 30, 31, 30, 31 +}; + +/* + * Days in each month in a leap year. + */ +static uint16_t leapyear[] = { + 31, 29, 31, 30, 31, 30, + 31, 31, 30, 31, 30, 31 +}; + +/* + * Variables used to remember parts of the last time conversion. Maybe we + * can avoid a full conversion. + */ +static uint32_t lasttime; +static uint32_t lastday; +static uint16_t lastddate; +static uint16_t 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 +msdos_date_unix2dos(unsigned int t, uint16_t *ddp, + uint16_t *dtp) +{ + uint32_t days; + uint32_t inc; + uint32_t year; + uint32_t month; + uint16_t *months; + + /* + * If the time from the last conversion is the same as now, then + * skip the computations and use the saved result. + */ + if (lasttime != t) { + lasttime = t; + lastdtime = (((t % 60) >> 1) << MSDOS_DT_2SECONDS_SHIFT) + + (((t / 60) % 60) << MSDOS_DT_MINUTES_SHIFT) + + (((t / 3600) % 24) << MSDOS_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 / (SECONDSPERDAY); + 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; month < 12; month++) { + if (days < months[month]) + break; + days -= months[month]; + } + lastddate = ((days + 1) << MSDOS_DD_DAY_SHIFT) + + ((month + 1) << MSDOS_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) << + MSDOS_DD_YEAR_SHIFT; + } + } + *dtp = lastdtime; + *ddp = lastddate; +} + +/* + * The number of days between Jan 1, 1970 and Jan 1, 1980. In that + * interval there were 8 regular years and 2 leap years. + */ +/* #define DAYSTO1980 ((8 * 365) + (2 * 366)) */ +#define DAYSTO1980 ((uint32_t) 3652) + +static uint16_t lastdosdate; +static uint32_t 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. + */ +unsigned int +msdos_date_dos2unix(unsigned int dd, unsigned int dt) +{ + uint32_t seconds; + uint32_t m, month; + uint32_t y, year; + uint32_t days; + uint16_t *months; + + seconds = 2 * ((dt & MSDOS_DT_2SECONDS_MASK) >> MSDOS_DT_2SECONDS_SHIFT) + + ((dt & MSDOS_DT_MINUTES_MASK) >> MSDOS_DT_MINUTES_SHIFT) * 60 + + ((dt & MSDOS_DT_HOURS_MASK) >> MSDOS_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 & MSDOS_DD_YEAR_MASK) >> MSDOS_DD_YEAR_SHIFT; + for (y = 0; y < year; y++) + days += y & 0x03 ? 365 : 366; + months = year & 0x03 ? regyear : leapyear; + /* + * Prevent going from 0 to 0xffffffff in the following + * loop. + */ + month = (dd & MSDOS_DD_MONTH_MASK) >> MSDOS_DD_MONTH_SHIFT; + if (month == 0) { + month = 1; + } + for (m = 0; m < month - 1; m++) + days += months[m]; + days += ((dd & MSDOS_DD_DAY_MASK) >> MSDOS_DD_DAY_SHIFT) - 1; + lastseconds = (days + DAYSTO1980) * SECONDSPERDAY; + } + return seconds + lastseconds; +} + +static const uint8_t msdos_map[] = { + 0, 0, 0, 0, 0, 0, 0, 0, /* 00-07 */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 08-0f */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 10-17 */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 18-1f */ + 0, '!', 0, '#', '$', '%', '&', '\'', /* 20-27 */ + '(', ')', 0, '+', 0, '-', 0, 0, /* 28-2f */ + '0', '1', '2', '3', '4', '5', '6', '7', /* 30-37 */ + '8', '9', 0, 0, 0, 0, 0, 0, /* 38-3f */ + '@', 'A', 'B', 'C', 'D', 'E', 'F', 'G', /* 40-47 */ + 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', /* 48-4f */ + 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', /* 50-57 */ + 'X', 'Y', 'Z', 0, 0, 0, '^', '_', /* 58-5f */ + '`', 'A', 'B', 'C', 'D', 'E', 'F', 'G', /* 60-67 */ + 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', /* 68-6f */ + 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', /* 70-77 */ + 'X', 'Y', 'Z', '{', 0, '}', '~', 0, /* 78-7f */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 80-87 */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 88-8f */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 90-97 */ + 0, 0, 0, 0, 0, 0, 0, 0, /* 98-9f */ + 0, 0xad, 0xbd, 0x9c, 0xcf, 0xbe, 0xdd, 0xf5, /* a0-a7 */ + 0xf9, 0xb8, 0xa6, 0xae, 0xaa, 0xf0, 0xa9, 0xee, /* a8-af */ + 0xf8, 0xf1, 0xfd, 0xfc, 0xef, 0xe6, 0xf4, 0xfa, /* b0-b7 */ + 0xf7, 0xfb, 0xa7, 0xaf, 0xac, 0xab, 0xf3, 0xa8, /* b8-bf */ + 0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80, /* c0-c7 */ + 0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8, /* c8-cf */ + 0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0x9e, /* d0-d7 */ + 0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0xe1, /* d8-df */ + 0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80, /* e0-e7 */ + 0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8, /* e8-ef */ + 0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0xf6, /* f0-f7 */ + 0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0x98, /* f8-ff */ +#if OLD_TABLE +/* 00 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 08 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 10 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 18 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 20 */ 0x00, 0x21, 0x00, 0x23, 0x24, 0x25, 0x26, 0x27, /* !"#$%&' */ +/* 28 */ 0x28, 0x29, 0x00, 0x00, 0x00, 0x2D, 0x2E, 0x00, /* ()*+,-./ */ +/* 30 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 01234567 */ +/* 38 */ 0x38, 0x39, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 89:;<=>? */ +/* 40 */ 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* @ABCDEFG */ +/* 48 */ 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, /* HIJKLMNO */ +/* 50 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* PQRSTUVW */ +/* 58 */ 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x00, 0x5E, 0x5F, /* XYZ[\]^_ */ +/* 60 */ 0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* `abcdefg */ +/* 68 */ 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, /* hijklmno */ +/* 70 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* pqrstuvw */ +/* 78 */ 0x58, 0x59, 0x5A, 0x5B, 0x7C, 0x00, 0x7E, 0x00, /* xyz{|}~ */ +/* 80 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 88 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 90 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* 98 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* A0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* A8 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* B0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* B8 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* C0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* C8 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* D0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* D8 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* E0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* E8 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* F0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +/* F8 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +#endif +}; +/* + * Convert a unix filename to a DOS filename. Return -1 if wrong name is + * supplied. + */ +int +msdos_filename_unix2dos(const char *un, int unlen, char *dn) +{ + int i; + uint8_t 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 0; + } + if (un[0] == '.' && un[1] == '.' && unlen == 2) { + dn[0] = '.'; + dn[1] = '.'; + return 0; + } + + /* + * Remove any dots from the start of a file name. + */ + while (unlen && (*un == '.')) { + un++; + unlen--; + } + + /* + * 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++) { + if (msdos_map[c] == 0) + break; + dn[i] = msdos_map[c]; + un++; + unlen--; + } + + /* + * 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++) { + if (msdos_map[c] == 0) + break; + dn[i] = msdos_map[c]; + un++; + unlen--; + } + return 0; +} |