name.c

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/*
 *  linux/fs/hpfs/name.c
 *
 *  Mikulas Patocka ([email protected]), 1998-1999
 *
 *  operations with filenames
 */

#include "hpfs_fn.h"

static inline int not_allowed_char(unsigned char c)
{
    return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
          c=='>' || c=='?' || c=='\\' || c=='|';
}

static inline int no_dos_char(unsigned char c)
{   /* Characters that are allowed in HPFS but not in DOS */
    return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
}

static inline unsigned char upcase(unsigned char *dir, unsigned char a)
{
    if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
    if (!dir) return a;
    return dir[a-128];
}

unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
{
    return upcase(dir, a);
}

static inline unsigned char locase(unsigned char *dir, unsigned char a)
{
    if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
    if (!dir) return a;
    return dir[a];
}

int hpfs_chk_name(const unsigned char *name, unsigned *len)
{
    int i;
    if (*len > 254) return -ENAMETOOLONG;
    hpfs_adjust_length(name, len);
    if (!*len) return -EINVAL;
    for (i = 0; i < *len; i++) if (not_allowed_char(name[i])) return -EINVAL;
    if (*len == 1) if (name[0] == '.') return -EINVAL;
    if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
    return 0;
}

unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,
              unsigned len, int lc, int lng)
{
    unsigned char *to;
    int i;
    if (hpfs_sb(s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {
        printk("HPFS: Long name flag mismatch - name ");
        for (i=0; i<len; i++) printk("%c", from[i]);
        printk(" misidentified as %s.\n", lng ? "short" : "long");
        printk("HPFS: It's nothing serious. It could happen because of bug in OS/2.\nHPFS: Set checks=normal to disable this message.\n");
    }
    if (!lc) return from;
    if (!(to = kmalloc(len, GFP_KERNEL))) {
        printk("HPFS: can't allocate memory for name conversion buffer\n");
        return from;
    }
    for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
    return to;
}

int hpfs_compare_names(struct super_block *s,
               const unsigned char *n1, unsigned l1,
               const unsigned char *n2, unsigned l2, int last)
{
    unsigned l = l1 < l2 ? l1 : l2;
    unsigned i;
    if (last) return -1;
    for (i = 0; i < l; i++) {
        unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
        unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
        if (c1 < c2) return -1;
        if (c1 > c2) return 1;
    }
    if (l1 < l2) return -1;
    if (l1 > l2) return 1;
    return 0;
}

int hpfs_is_name_long(const unsigned char *name, unsigned len)
{
    int i,j;
    for (i = 0; i < len && name[i] != '.'; i++)
        if (no_dos_char(name[i])) return 1;
    if (!i || i > 8) return 1;
    if (i == len) return 0;
    for (j = i + 1; j < len; j++)
        if (name[j] == '.' || no_dos_char(name[i])) return 1;
    return j - i > 4;
}

/* OS/2 clears dots and spaces at the end of file name, so we have to */

void hpfs_adjust_length(const unsigned char *name, unsigned *len)
{
    if (!*len) return;
    if (*len == 1 && name[0] == '.') return;
    if (*len == 2 && name[0] == '.' && name[1] == '.') return;
    while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
        (*len)--;
}