1  
       2  /* contrib/mips-msa/linux.c
       3   *
       4   * Copyright (c) 2020 Cosmin Truta
       5   * Copyright (c) 2016 Glenn Randers-Pehrson
       6   * Written by Mandar Sahastrabuddhe, 2016.
       7   *
       8   * This code is released under the libpng license.
       9   * For conditions of distribution and use, see the disclaimer
      10   * and license in png.h
      11   *
      12   * SEE contrib/mips-msa/README before reporting bugs
      13   *
      14   * STATUS: SUPPORTED
      15   * BUG REPORTS: png-mng-implement@sourceforge.net
      16   *
      17   * png_have_msa implemented for Linux by reading the widely available
      18   * pseudo-file /proc/cpuinfo.
      19   *
      20   * This code is strict ANSI-C and is probably moderately portable; it does
      21   * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
      22   */
      23  
      24  #include <stdio.h>
      25  #include <string.h>
      26  #include <stdlib.h>
      27  
      28  static int
      29  png_have_msa(png_structp png_ptr)
      30  {
      31     FILE *f = fopen("/proc/cpuinfo", "rb");
      32  
      33     char *string = "msa";
      34     char word[10];
      35  
      36     if (f != NULL)
      37     {
      38        while(!feof(f))
      39        {
      40           int ch = fgetc(f);
      41           static int i = 0;
      42  
      43           while(!(ch <= 32))
      44           {
      45              word[i++] = ch;
      46              ch = fgetc(f);
      47           }
      48  
      49           int val = strcmp(string, word);
      50  
      51           if (val == 0) {
      52              fclose(f);
      53              return 1;
      54           }
      55  
      56           i = 0;
      57           memset(word, 0, 10);
      58        }
      59  
      60        fclose(f);
      61     }
      62  #ifdef PNG_WARNINGS_SUPPORTED
      63     else
      64        png_warning(png_ptr, "/proc/cpuinfo open failed");
      65  #endif
      66     return 0;
      67  }