fs/hpfs/name.c

   1 /*
   2  *  linux/fs/hpfs/name.c
   3  *
   4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   5  *
   6  *  operations with filenames
   7  */
   8
   9 #include "hpfs_fn.h"
  10
  11 static inline int not_allowed_char(unsigned char c)
  12 {
  13         return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
  14               c=='>' || c=='?' || c=='\\' || c=='|';
  15 }
  16
  17 static inline int no_dos_char(unsigned char c)
  18 {       /* Characters that are allowed in HPFS but not in DOS */
  19         return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
  20 }
  21
  22 static inline unsigned char upcase(unsigned char *dir, unsigned char a)
  23 {
  24         if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
  25         if (!dir) return a;
  26         return dir[a-128];
  27 }
  28
  29 unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
  30 {
  31         return upcase(dir, a);
  32 }
  33
  34 static inline unsigned char locase(unsigned char *dir, unsigned char a)
  35 {
  36         if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
  37         if (!dir) return a;
  38         return dir[a];
  39 }
  40
  41 int hpfs_chk_name(const unsigned char *name, unsigned *len)
  42 {
  43         int i;
  44         if (*len > 254) return -ENAMETOOLONG;
  45         hpfs_adjust_length(name, len);
  46         if (!*len) return -EINVAL;
  47         for (i = 0; i < *len; i++) if (not_allowed_char(name[i])) return -EINVAL;
  48         if (*len == 1) if (name[0] == '.') return -EINVAL;
  49         if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
  50         return 0;
  51 }
  52
  53 unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,
  54                           unsigned len, int lc, int lng)
  55 {
  56         unsigned char *to;
  57         int i;
  58         if (hpfs_sb(s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {
  59                 pr_err("Long name flag mismatch - name ");
  60                 for (i = 0; i < len; i++)
  61                         pr_cont("%c", from[i]);
  62                 pr_cont(" misidentified as %s.\n", lng ? "short" : "long");
  63                 pr_err("It's nothing serious. It could happen because of bug in OS/2.\nSet checks=normal to disable this message.\n");
  64         }
  65         if (!lc) return from;
  66         if (!(to = kmalloc(len, GFP_KERNEL))) {
  67                 pr_err("can't allocate memory for name conversion buffer\n");
  68                 return from;
  69         }
  70         for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
  71         return to;
  72 }
  73
  74 int hpfs_compare_names(struct super_block *s,
  75                        const unsigned char *n1, unsigned l1,
  76                        const unsigned char *n2, unsigned l2, int last)
  77 {
  78         unsigned l = l1 < l2 ? l1 : l2;
  79         unsigned i;
  80         if (last) return -1;
  81         for (i = 0; i < l; i++) {
  82                 unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
  83                 unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
  84                 if (c1 < c2) return -1;
  85                 if (c1 > c2) return 1;
  86         }
  87         if (l1 < l2) return -1;
  88         if (l1 > l2) return 1;
  89         return 0;
  90 }
  91
  92 int hpfs_is_name_long(const unsigned char *name, unsigned len)
  93 {
  94         int i,j;
  95         for (i = 0; i < len && name[i] != '.'; i++)
  96                 if (no_dos_char(name[i])) return 1;
  97         if (!i || i > 8) return 1;
  98         if (i == len) return 0;
  99         for (j = i + 1; j < len; j++)
 100                 if (name[j] == '.' || no_dos_char(name[i])) return 1;
 101         return j - i > 4;
 102 }
 103
 104 /* OS/2 clears dots and spaces at the end of file name, so we have to */
 105
 106 void hpfs_adjust_length(const unsigned char *name, unsigned *len)
 107 {
 108         if (!*len) return;
 109         if (*len == 1 && name[0] == '.') return;
 110         if (*len == 2 && name[0] == '.' && name[1] == '.') return;
 111         while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
 112                 (*len)--;
 113 }