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diff --git a/media/libpng/arm/linux.c b/media/libpng/arm/linux.c
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+/* contrib/arm-neon/linux.c
+ *
+ * Last changed in libpng 1.6.31 [July 27, 2017]
+ * Copyright (c) 2014, 2017 Glenn Randers-Pehrson
+ * Written by John Bowler, 2014, 2017.
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: SUPPORTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon 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>
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+ FILE *f = fopen("/proc/cpuinfo", "rb");
+
+ if (f != NULL)
+ {
+ /* This is a simple state machine which reads the input byte-by-byte until
+ * it gets a match on the 'neon' feature or reaches the end of the stream.
+ */
+ static const char ch_feature[] = { 70, 69, 65, 84, 85, 82, 69, 83 };
+ static const char ch_neon[] = { 78, 69, 79, 78 };
+
+ enum
+ {
+ StartLine, Feature, Colon, StartTag, Neon, HaveNeon, SkipTag, SkipLine
+ } state;
+ int counter;
+
+ for (state=StartLine, counter=0;;)
+ {
+ int ch = fgetc(f);
+
+ if (ch == EOF)
+ {
+ /* EOF means error or end-of-file, return false; neon at EOF is
+ * assumed to be a mistake.
+ */
+ fclose(f);
+ return 0;
+ }
+
+ switch (state)
+ {
+ case StartLine:
+ /* Match spaces at the start of line */
+ if (ch <= 32) /* skip control characters and space */
+ break;
+
+ counter=0;
+ state = Feature;
+ /* FALLTHROUGH */
+
+ case Feature:
+ /* Match 'FEATURE', ASCII case insensitive. */
+ if ((ch & ~0x20) == ch_feature[counter])
+ {
+ if (++counter == (sizeof ch_feature))
+ state = Colon;
+ break;
+ }
+
+ /* did not match 'feature' */
+ state = SkipLine;
+ /* FALLTHROUGH */
+
+ case SkipLine:
+ skipLine:
+ /* Skip everything until we see linefeed or carriage return */
+ if (ch != 10 && ch != 13)
+ break;
+
+ state = StartLine;
+ break;
+
+ case Colon:
+ /* Match any number of space or tab followed by ':' */
+ if (ch == 32 || ch == 9)
+ break;
+
+ if (ch == 58) /* i.e. ':' */
+ {
+ state = StartTag;
+ break;
+ }
+
+ /* Either a bad line format or a 'feature' prefix followed by
+ * other characters.
+ */
+ state = SkipLine;
+ goto skipLine;
+
+ case StartTag:
+ /* Skip space characters before a tag */
+ if (ch == 32 || ch == 9)
+ break;
+
+ state = Neon;
+ counter = 0;
+ /* FALLTHROUGH */
+
+ case Neon:
+ /* Look for 'neon' tag */
+ if ((ch & ~0x20) == ch_neon[counter])
+ {
+ if (++counter == (sizeof ch_neon))
+ state = HaveNeon;
+ break;
+ }
+
+ state = SkipTag;
+ /* FALLTHROUGH */
+
+ case SkipTag:
+ /* Skip non-space characters */
+ if (ch == 10 || ch == 13)
+ state = StartLine;
+
+ else if (ch == 32 || ch == 9)
+ state = StartTag;
+ break;
+
+ case HaveNeon:
+ /* Have seen a 'neon' prefix, but there must be a space or new
+ * line character to terminate it.
+ */
+ if (ch == 10 || ch == 13 || ch == 32 || ch == 9)
+ {
+ fclose(f);
+ return 1;
+ }
+
+ state = SkipTag;
+ break;
+
+ default:
+ png_error(png_ptr, "png_have_neon: internal error (bug)");
+ }
+ }
+ }
+
+#ifdef PNG_WARNINGS_SUPPORTED
+ else
+ png_warning(png_ptr, "/proc/cpuinfo open failed");
+#endif
+
+ return 0;
+}