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 void edid_state::parse_string_table(const unsigned char *x)
  19 {
  20         unsigned width = 1 << (x[0] & 7);
  21
  22         printf("  UTF Type: ");
  23         switch (x[0] & 7) {
  24         case 0: printf("UTF 8\n"); break;
  25         case 1: printf("UTF 16BE\n"); break;
  26         case 2: printf("UTF 32BE\n"); break;
  27         default:
  28                 printf("Unknown (0x%02x)\n", x[0] & 7);
  29                 fail("Unknown UTF Type (0x%02x).\n", x[0] & 7);
  30                 break;
  31         }
  32         printf("  Country Code ID (ISO 3166-3): %u\n", ((x[1] & 0x3f) << 8) | x[2]);
  33
  34         if (x[3] || x[4]) {
  35                 char name[4];
  36
  37                 name[0] = ((x[3] & 0x7c) >> 2) + '@';
  38                 name[1] = ((x[3] & 0x03) << 3) + ((x[4] & 0xe0) >> 5) + '@';
  39                 name[2] = (x[4] & 0x1f) + '@';
  40                 name[3] = 0;
  41                 if (name[0] == '@') name[0] = ' ';
  42                 if (name[1] == '@') name[1] = ' ';
  43                 if (name[2] == '@') name[2] = ' ';
  44                 printf("  Language ID: '%s'\n", name);
  45         }
  46         x += 5;
  47         parse_string("Manufacturer Name", x);
  48         if (x[0] % width)
  49                 fail("Incorrect Manufacturer Name length.\n");
  50         x += x[0] + 1;
  51         parse_string("Model Name", x);
  52         if (x[0] % width)
  53                 fail("Incorrect Model Name length.\n");
  54         x += x[0] + 1;
  55         if (hide_serial_numbers)
  56                 printf("  Serial Number: ...\n");
  57         else
  58                 parse_string("Serial Number", x);
  59         if (x[0] % width)
  60                 fail("Incorrect Serial Number length.\n");
  61 }
  62
  63 void edid_state::preparse_ls_ext_block(unsigned char *x)
  64 {
  65         unsigned char *orig = x;
  66
  67         if (!replace_unique_ids)
  68                 return;
  69
  70         x += 5;
  71
  72         while (x[0] && x + x[0] < orig + 127) {
  73                 unsigned width = 1 << (x[1] & 7);
  74                 unsigned char *s = x + 6;
  75
  76                 x += x[0];
  77                 if (width > 4)
  78                         continue;
  79
  80                 s += s[0] + 1;
  81                 s += s[0] + 1;
  82                 for (unsigned i = 1; i <= s[0]; i += width) {
  83                         unsigned idx = (i - 1) / width;
  84
  85                         memset(s + i, 0, width - 1);
  86                         s[i + width - 1] = idx < 6 ? '1' + idx : ' ';
  87                 }
  88         }
  89         replace_checksum(orig, EDID_PAGE_SIZE);
  90 }
  91
  92 void edid_state::parse_ls_ext_block(const unsigned char *x)
  93 {
  94         const unsigned char *orig = x;
  95
  96         printf("  Version: %u.%u\n  Unicode Version: %u.%u.%u\n",
  97                x[1], x[2], (x[3] >> 4), x[3] & 0x0f, x[4]);
  98         x += 5;
  99
 100         while (x[0] && x + x[0] < orig + 127) {
 101                 parse_string_table(x + 1);
 102                 x += x[0];
 103         }
 104         unused_bytes = orig + 127 - x;
 105         if (!memchk(x, unused_bytes)) {
 106                 data_block.clear();
 107                 fail("Non-zero values in unused space.\n");
 108         }
 109 }