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Diffstat (limited to 'Build/source/libs/libpng/libpng-1.6.16/contrib/arm-neon/linux-auxv.c')
-rw-r--r--Build/source/libs/libpng/libpng-1.6.16/contrib/arm-neon/linux-auxv.c120
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diff --git a/Build/source/libs/libpng/libpng-1.6.16/contrib/arm-neon/linux-auxv.c b/Build/source/libs/libpng/libpng-1.6.16/contrib/arm-neon/linux-auxv.c
deleted file mode 100644
index 696e297ef4c..00000000000
--- a/Build/source/libs/libpng/libpng-1.6.16/contrib/arm-neon/linux-auxv.c
+++ /dev/null
@@ -1,120 +0,0 @@
-/* contrib/arm-neon/linux-auxv.c
- *
- * Copyright (c) 2014 Glenn Randers-Pehrson
- * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.10 [March 6, 2014]
- *
- * 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: COMPILED, TESTED
- * BUG REPORTS: png-mng-implement@sourceforge.net
- *
- * png_have_neon implemented for Linux versions which allow access to
- * /proc/self/auxv. This is probably faster, cleaner and safer than the code to
- * read /proc/cpuinfo in contrib/arm-neon/linux, however it is yet another piece
- * of potentially untested code and has more complex dependencies than the code
- * to read cpuinfo.
- *
- * This generic __linux__ implementation requires reading /proc/self/auxv and
- * looking at each element for one that records NEON capabilities.
- */
-#include <unistd.h> /* for POSIX 1003.1 */
-#include <errno.h> /* for EINTR */
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <elf.h>
-#include <asm/hwcap.h>
-
-/* A read call may be interrupted, in which case it returns -1 and sets errno to
- * EINTR if nothing was done, otherwise (if something was done) a partial read
- * may result.
- */
-static size_t
-safe_read(png_structp png_ptr, int fd, void *buffer_in, size_t nbytes)
-{
- size_t ntotal = 0;
- char *buffer = png_voidcast(char*, buffer_in);
-
- while (nbytes > 0)
- {
- unsigned int nread;
- int iread;
-
- /* Passing nread > INT_MAX to read is implementation defined in POSIX
- * 1003.1, therefore despite the unsigned argument portable code must
- * limit the value to INT_MAX!
- */
- if (nbytes > INT_MAX)
- nread = INT_MAX;
-
- else
- nread = (unsigned int)/*SAFE*/nbytes;
-
- iread = read(fd, buffer, nread);
-
- if (iread == -1)
- {
- /* This is the devil in the details, a read can terminate early with 0
- * bytes read because of EINTR, yet it still returns -1 otherwise end
- * of file cannot be distinguished.
- */
- if (errno != EINTR)
- {
- png_warning(png_ptr, "/proc read failed");
- return 0; /* I.e., a permanent failure */
- }
- }
-
- else if (iread < 0)
- {
- /* Not a valid 'read' result: */
- png_warning(png_ptr, "OS /proc read bug");
- return 0;
- }
-
- else if (iread > 0)
- {
- /* Continue reading until a permanent failure, or EOF */
- buffer += iread;
- nbytes -= (unsigned int)/*SAFE*/iread;
- ntotal += (unsigned int)/*SAFE*/iread;
- }
-
- else
- return ntotal;
- }
-
- return ntotal; /* nbytes == 0 */
-}
-
-static int
-png_have_neon(png_structp png_ptr)
-{
- int fd = open("/proc/self/auxv", O_RDONLY);
- Elf32_auxv_t aux;
-
- /* Failsafe: failure to open means no NEON */
- if (fd == -1)
- {
- png_warning(png_ptr, "/proc/self/auxv open failed");
- return 0;
- }
-
- while (safe_read(png_ptr, fd, &aux, sizeof aux) == sizeof aux)
- {
- if (aux.a_type == AT_HWCAP && (aux.a_un.a_val & HWCAP_NEON) != 0)
- {
- close(fd);
- return 1;
- }
- }
-
- close(fd);
- return 0;
-}