Merge pull request #666 from iburinoc/zstdmt-default

Add MT enabled targets for libzstd

lib/Makefile

@@ -71,6 +71,9 @@ libzstd.a: $(ZSTD_OBJ)
 	@echo compiling static library
 	@$(AR) $(ARFLAGS) $@ $^
 
+libzstd.a-mt: CPPFLAGS += -DZSTD_MULTHREAD
+libzstd.a-mt: libzstd.a
+
 $(LIBZSTD): LDFLAGS += -shared -fPIC -fvisibility=hidden
 $(LIBZSTD): $(ZSTD_FILES)
 	@echo compiling dynamic library $(LIBVER)
@@ -86,10 +89,17 @@ endif
 
 libzstd : $(LIBZSTD)
 
+libzstd-mt : CPPFLAGS += -DZSTD_MULTITHREAD
+libzstd-mt : libzstd
+
 lib: libzstd.a libzstd
 
-lib-release: DEBUGFLAGS :=
+lib-mt: CPPFLAGS += -DZSTD_MULTITHREAD
+lib-mt: lib
+
+lib-release lib-release-mt: DEBUGFLAGS :=
 lib-release: lib
+lib-release-mt: lib-mt
 
 clean:
 	@$(RM) -r *.dSYM   # Mac OS-X specific

lib/README.md

@@ -22,6 +22,14 @@ Some additional API may be useful if you're looking into advanced features :
                           They are not "stable", their definition may change in the future.
                           Only static linking is allowed.
 
+#### ZSTDMT API
+
+To enable building the multithreaded compression API, use the `make lib-mt` target.
+The header file zstdmt_compress.h (in compress/) provides the prototypes for the API.
+If linking a program that uses the ZSTDMT API against libzstd.a on a POSIX system,
+the -pthread flag must be provided to the compiler at link time.
+Note that these prototypes may still be used in a version built without multithread support,
+but they will be single threaded (i.e. no benefits will be given over the standard ZSTD API).
 
 #### Modular build