lib/e2p/encoding.c

   1 /*
   2  * encoding.c --- convert between encoding magic numbers and strings
   3  *
   4  * Copyright (C) 2018  Collabora Ltd.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Library
   8  * General Public License, version 2.
   9  * %End-Header%
  10  */
  11
  12 #include "config.h"
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <ctype.h>
  17 #include <errno.h>
  18 #include <stdio.h>
  19
  20 #include "e2p.h"
  21
  22 #define ARRAY_SIZE(array)                       \
  23         (sizeof(array) / sizeof(array[0]))
  24
  25 static const struct {
  26         char *name;
  27         __u16 encoding_magic;
  28         __u16 default_flags;
  29
  30 } ext4_encoding_map[] = {
  31         {
  32                 .encoding_magic = EXT4_ENC_ASCII,
  33                 .name = "ascii",
  34                 .default_flags = 0
  35         },
  36         {
  37                 .encoding_magic = EXT4_ENC_UTF8_11_0,
  38                 .name = "utf8",
  39                 .default_flags = (EXT4_UTF8_NORMALIZATION_TYPE_NFKD |
  40                                   EXT4_UTF8_CASEFOLD_TYPE_NFKDCF)
  41         },
  42 };
  43
  44 static const struct enc_flags {
  45         __u16 flag;
  46         char *param;
  47 } encoding_flags[] = {
  48         { EXT4_ENC_STRICT_MODE_FL, "strict" },
  49 };
  50
  51 /* Return a positive number < 0xff indicating the encoding magic number
  52  * or a negative value indicating error. */
  53 int e2p_str2encoding(const char *string)
  54 {
  55         int i;
  56
  57         for (i = 0 ; i < ARRAY_SIZE(ext4_encoding_map); i++)
  58                 if (!strcmp(string, ext4_encoding_map[i].name))
  59                         return ext4_encoding_map[i].encoding_magic;
  60
  61         return -EINVAL;
  62 }
  63
  64 int e2p_get_encoding_flags(int encoding)
  65 {
  66         int i;
  67
  68         for (i = 0 ; i < ARRAY_SIZE(ext4_encoding_map); i++)
  69                 if (ext4_encoding_map[i].encoding_magic == encoding)
  70                         return ext4_encoding_map[encoding].default_flags;
  71
  72         return 0;
  73 }
  74
  75 int e2p_str2encoding_flags(int encoding, char *param, __u16 *flags)
  76 {
  77         char *f = strtok(param, "-");
  78         const struct enc_flags *fl;
  79         int i, neg = 0;
  80
  81         while (f) {
  82                 neg = 0;
  83                 if (!strncmp("no", f, 2)) {
  84                         neg = 1;
  85                         f += 2;
  86                 }
  87
  88                 for (i = 0; i < ARRAY_SIZE(encoding_flags); i++) {
  89                         fl = &encoding_flags[i];
  90                         if (!strcmp(fl->param, f)) {
  91                                 if (neg)
  92                                         *flags &= ~fl->flag;
  93                                 else
  94                                         *flags |= fl->flag;
  95
  96                                 goto next_flag;
  97                         }
  98                 }
  99                 return -EINVAL;
 100         next_flag:
 101                 f = strtok(NULL, "-");
 102         }
 103         return 0;
 104 }