Add unit tests to seekable

contrib/seekable_format/tests/Makefile

@@ -0,0 +1,38 @@
+# ################################################################
+# Copyright (c) 2017-present, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under both the BSD-style license (found in the
+# LICENSE file in the root directory of this source tree) and the GPLv2 (found
+# in the COPYING file in the root directory of this source tree).
+# ################################################################
+
+# This Makefile presumes libzstd is built, using `make` in / or /lib/
+
+ZSTDLIB_PATH = ../../../lib
+ZSTDLIB_NAME = libzstd.a
+ZSTDLIB = $(ZSTDLIB_PATH)/$(ZSTDLIB_NAME)
+
+CPPFLAGS += -I../ -I../../../lib -I../../../lib/common
+
+CFLAGS ?= -O3
+CFLAGS += -g
+
+SEEKABLE_OBJS = ../zstdseek_compress.c ../zstdseek_decompress.c $(ZSTDLIB)
+
+.PHONY: default clean test
+
+default: test
+
+test: seekable_tests
+
+$(ZSTDLIB):
+	make -C $(ZSTDLIB_PATH) $(ZSTDLIB_NAME)
+
+seekable_tests : seekable_tests.c $(SEEKABLE_OBJS)
+	$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
+
+clean:
+	@rm -f core *.o tmp* result* *.zst \
+		seekable_tests
+	@echo Cleaning completed