chore: import upstream snapshot with attribution

third_party/png/BUILD.bazel

@@ -0,0 +1 @@
+# copybara:uncomment package(default_applicable_licenses = ["//tensorflow:license"])

third_party/png/png.BUILD

@@ -0,0 +1,70 @@
+# Description:
+#   libpng is the official PNG reference library.
+
+licenses(["notice"])  # BSD/MIT-like license
+
+exports_files(["LICENSE"])
+
+cc_library(
+    name = "png",
+    srcs = [
+        "png.c",
+        "pngdebug.h",
+        "pngerror.c",
+        "pngget.c",
+        "pnginfo.h",
+        "pnglibconf.h",
+        "pngmem.c",
+        "pngpread.c",
+        "pngpriv.h",
+        "pngread.c",
+        "pngrio.c",
+        "pngrtran.c",
+        "pngrutil.c",
+        "pngset.c",
+        "pngstruct.h",
+        "pngtrans.c",
+        "pngwio.c",
+        "pngwrite.c",
+        "pngwtran.c",
+        "pngwutil.c",
+    ] + select({
+        ":windows": [
+            "intel/filter_sse2_intrinsics.c",
+            "intel/intel_init.c",
+        ],
+        "@xla//xla/tsl:linux_ppc64le": [
+            "powerpc/filter_vsx_intrinsics.c",
+            "powerpc/powerpc_init.c",
+        ],
+        "//conditions:default": [
+        ],
+    }),
+    hdrs = [
+        "png.h",
+        "pngconf.h",
+    ],
+    copts = select({
+        ":windows": ["-DPNG_INTEL_SSE_OPT=1"],
+        "//conditions:default": [],
+    }),
+    includes = ["."],
+    linkopts = select({
+        ":windows": [],
+        "//conditions:default": ["-lm"],
+    }),
+    visibility = ["//visibility:public"],
+    deps = ["@zlib"],
+)
+
+genrule(
+    name = "snappy_stubs_public_h",
+    srcs = ["scripts/pnglibconf.h.prebuilt"],
+    outs = ["pnglibconf.h"],
+    cmd = "sed -e 's/PNG_ZLIB_VERNUM 0/PNG_ZLIB_VERNUM 0x1310/' $< >$@",
+)
+
+config_setting(
+    name = "windows",
+    constraint_values = ["@platforms//os:windows"],
+)

third_party/png/png_fix_rpi.patch

@@ -0,0 +1,16 @@
+diff -r -u ./scripts/pnglibconf.h.prebuilt ./scripts/pnglibconf.h.prebuilt
+--- ./scripts/pnglibconf.h.prebuilt
++++ ./scripts/pnglibconf.h.prebuilt
+@@ -19,6 +19,12 @@
+ #define PNG_ALIGNED_MEMORY_SUPPORTED
+ /*#undef PNG_ARM_NEON_API_SUPPORTED*/
+ /*#undef PNG_ARM_NEON_CHECK_SUPPORTED*/
++
++/* Workaround not having a great build file by forcing
++ * png filter optimization to be disabled on arm */
++#define PNG_ARM_NEON_OPT 0
++
++
+ #define PNG_BENIGN_ERRORS_SUPPORTED
+ #define PNG_BENIGN_READ_ERRORS_SUPPORTED
+ /*#undef PNG_BENIGN_WRITE_ERRORS_SUPPORTED*/

third_party/png/workspace.bzl

@@ -0,0 +1,14 @@
+"""Loads the png library, used by TF."""
+
+load("//third_party:repo.bzl", "tf_http_archive", "tf_mirror_urls")
+
+def repo():
+    tf_http_archive(
+        name = "png",
+        build_file = "//third_party/png:png.BUILD",
+        patch_file = ["//third_party/png:png_fix_rpi.patch"],
+        sha256 = "fecc95b46cf05e8e3fc8a414750e0ba5aad00d89e9fdf175e94ff041caf1a03a",
+        strip_prefix = "libpng-1.6.43",
+        system_build_file = "//third_party/systemlibs:png.BUILD",
+        urls = tf_mirror_urls("https://github.com/glennrp/libpng/archive/v1.6.43.tar.gz"),
+    )