parse-ls-ext-block.cpp

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright 2019-2020 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
   4  *
   5  * Author: Hans Verkuil <hverkuil-cisco@xs4all.nl>
   6  */
   7
   8 #include "edid-decode.h"
   9
  10 static void parse_string(const char *name, const unsigned char *x)
  11 {
  12         if (!*x)
  13                 return;
  14         printf("  %s: ", name);
  15         hex_block("", x + 1, *x, true, *x);
  16 }
  17
  18 // Note that support for UTF 16BE and 32BE is missing.
  19 // I have never seen LS-EXT support in real EDIDs, so that
  20 // shouldn't be a problem.
  21 void edid_state::parse_string_table(const unsigned char *x)
  22 {
  23         printf("  UTF Type: ");
  24         switch (x[0] & 7) {
  25         case 0: printf("UTF 8\n"); break;
  26         case 1: printf("UTF 16BE\n"); break;
  27         case 2: printf("UTF 32BE\n"); break;
  28         default:
  29                 printf("Unknown (0x%02x)\n", x[0] & 7);
  30                 fail("Unknown UTF Type (0x%02x).\n", x[0] & 7);
  31                 break;
  32         }
  33         printf("  Country Code ID (ISO 3166-3): %u\n", ((x[1] & 0x3f) << 8) | x[2]);
  34
  35         if (x[3] || x[4]) {
  36                 char name[4];
  37
  38                 name[0] = ((x[3] & 0x7c) >> 2) + '@';
  39                 name[1] = ((x[3] & 0x03) << 3) + ((x[4] & 0xe0) >> 5) + '@';
  40                 name[2] = (x[4] & 0x1f) + '@';
  41                 name[3] = 0;
  42                 if (name[0] == '@') name[0] = ' ';
  43                 if (name[1] == '@') name[1] = ' ';
  44                 if (name[2] == '@') name[2] = ' ';
  45                 printf("  Language ID: '%s'\n", name);
  46         }
  47         x += 5;
  48         parse_string("Manufacturer Name", x);
  49         x += x[0] + 1;
  50         parse_string("Model Name", x);
  51         x += x[0] + 1;
  52         if (hide_serial_numbers)
  53                 printf("  Serial Number: ...\n");
  54         else
  55                 parse_string("Serial Number", x);
  56 }
  57
  58 void edid_state::preparse_ls_ext_block(unsigned char *x)
  59 {
  60         unsigned char *orig = x;
  61
  62         if (!replace_serial_numbers)
  63                 return;
  64
  65         x += 5;
  66
  67         while (x[0] && x + x[0] < orig + 127) {
  68                 unsigned char *s = x + 6;
  69
  70                 s += s[0] + 1;
  71                 s += s[0] + 1;
  72                 for (unsigned i = 1; i <= s[0]; i++)
  73                         s[i] = i <= 6 ? '0' + i : ' ';
  74                 x += x[0];
  75         }
  76 }
  77
  78 void edid_state::parse_ls_ext_block(const unsigned char *x)
  79 {
  80         const unsigned char *orig = x;
  81
  82         printf("  Version: %u.%u\n  Unicode Version: %u.%u.%u\n",
  83                x[1], x[2], (x[3] >> 4), x[3] & 0x0f, x[4]);
  84         x += 5;
  85
  86         while (x[0] && x + x[0] < orig + 127) {
  87                 parse_string_table(x + 1);
  88                 x += x[0];
  89         }
  90         unused_bytes = orig + 127 - x;
  91         if (!memchk(x, unused_bytes)) {
  92                 data_block.clear();
  93                 fail("Non-zero values in unused space.\n");
  94         }
  95 }