Fuchsia build configuration for bzip2

Change-Id: I026d0cb32c12ef13118e21f3e2e47f82f14cf61b
diff --git a/BUILD.gn b/BUILD.gn
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+++ b/BUILD.gn
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+# Copyright 2017 The Fuchsia Authors. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#    * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#    * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#    * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+config("bz2_config") {
+  include_dirs = [ "." ]
+}
+
+config("bz2_warnings") {
+  visibility = [ ":*" ]
+  cflags = [
+    "-Wno-int-conversion",
+    "-Wno-implicit-function-declaration",
+  ]
+}
+
+shared_library("bz2") {
+  public_configs = [ ":bz2_config" ]
+  sources = [
+    "blocksort.c",
+    "bzlib.c",
+    "compress.c",
+    "crctable.c",
+    "decompress.c",
+    "huffman.c",
+    "randtable.c",
+  ]
+  configs += [ ":bz2_warnings" ]
+  configs -= [ "//build/config:symbol_visibility_hidden" ]
+}
+
+executable("bzip2") {
+  sources = [
+    "bzip2.c",
+  ]
+  deps = [
+    ":bz2",
+  ]
+}
+
+executable("bzip2recover") {
+  sources = [
+    "bzip2recover.c",
+  ]
+  deps = [
+    ":bz2",
+  ]
+}