Changeset 103316 in vbox for trunk/src/libs/libpng-1.6.42/contrib/mips-msa

Timestamp:

Feb 12, 2024 3:57:56 PM (12 months ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

161613

Message:

libpng-1.6.42: Applied and adjusted our libpng changes to 1.6.42. bugref:8515

File:

• trunk/src/libs/libpng-1.6.42/contrib/mips-msa/linux.c (modified) (2 diffs)

trunk/src/libs/libpng-1.6.42/contrib/mips-msa/linux.c

@@ +1 @@
+
 /* contrib/mips-msa/linux.c
  *
+ * Copyright (c) 2020-2023 Cosmin Truta
  * Copyright (c) 2016 Glenn Randers-Pehrson
  * Written by Mandar Sahastrabuddhe, 2016.
- * Last changed in libpng 1.6.25beta03 [August 29, 2016]
+ * Updated by Sui Jingfeng, 2021.
  *
  * This code is released under the libpng license.
@@ -9 +11 @@
  * and license in png.h
  *
- * SEE contrib/mips-msa/README before reporting bugs
+ * On Linux, png_have_msa is implemented by reading the pseudo-file
+ * "/proc/self/auxv".
+ *
+ * See contrib/mips-msa/README before reporting bugs.
  *
  * STATUS: SUPPORTED
  * BUG REPORTS: [email protected]
- *
- * png_have_msa implemented for Linux by reading the widely available
- * pseudo-file /proc/cpuinfo.
- *
- * This code is strict ANSI-C and is probably moderately portable; it does
- * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
  */
 
-#include <stdio.h>
-#include <string.h>
+#include <elf.h>
+#include <fcntl.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 static int
 png_have_msa(png_structp png_ptr)
 {
-   FILE *f = fopen("/proc/cpuinfo", "rb");
+   Elf64_auxv_t aux;
+   int fd;
+   int has_msa = 0;
 
-   char *string = "msa";
-   char word[10];
+   fd = open("/proc/self/auxv", O_RDONLY);
+   if (fd >= 0)
+   {
+      while (read(fd, &aux, sizeof(Elf64_auxv_t)) == sizeof(Elf64_auxv_t))
+      {
+         if (aux.a_type == AT_HWCAP)
+         {
+            uint64_t hwcap = aux.a_un.a_val;
 
-   if (f != NULL)
-   {
-      while(!feof(f))
-      {
-         int ch = fgetc(f);
-         static int i = 0;
-
-         while(!(ch <= 32))
-         {
-            word[i++] = ch;
-            ch = fgetc(f);
+            has_msa = (hwcap >> 1) & 1;
+            break;
          }
-
-         int val = strcmp(string, word);
-
-         if (val == 0)
-            return 1;
-
-         i = 0;
-         memset(word, 0, 10);
       }
-
-      fclose(f);
+      close(fd);
    }
 #ifdef PNG_WARNINGS_SUPPORTED
    else
-      png_warning(png_ptr, "/proc/cpuinfo open failed");
+      png_warning(png_ptr, "/proc/self/auxv open failed");
 #endif
-   return 0;
+
+   return has_msa;
 }