buck: build zstd

Signed-off-by: Austin Seipp <aseipp@pobox.com>

buck/third-party/zstd/BUILD

@@ -0,0 +1,32 @@
+
+load("@root//buck/shims/jj.bzl", "jj")
+
+# XXX FIXME (aseipp): download the real source, not my copy of zstd i amalgamated a few months ago
+
+http_archive(
+    name = 'src',
+    sha256 = '3dde08c4ceb16a1de42ed4008fa52eda01fc1b8b115012e8216b9f6d910db9e5',
+    urls = [
+        'https://gist.github.com/thoughtpolice/bb26bee5c02e8986760210b291e43288/archive/6bcf321e242d62765c640458cd98d407e84f33a1.tar.gz',
+    ],
+    type = 'tar.gz',
+    strip_prefix = "bb26bee5c02e8986760210b291e43288-6bcf321e242d62765c640458cd98d407e84f33a1",
+    sub_targets = [
+        'zstd.h',
+        'zdict.h',
+        'zstd_errors.h',
+        'zstd.c',
+    ]
+)
+
+jj.cxx_library(
+    name = 'zstd',
+    header_namespace = 'zstd',
+    exported_headers = {
+        'zstd.h': ':src[zstd.h]',
+        'zdict.h': ':src[zdict.h]',
+        'zstd_errors.h': ':src[zstd_errors.h]',
+    },
+    srcs = [ ':src[zstd.c]' ],
+    preferred_linkage = "static",
+)

buck/third-party/zstd/PACKAGE

@@ -0,0 +1,5 @@
+
+package(
+    inherit = True,
+    visibility = [ 'PUBLIC' ],
+)