added target lz4-wlib

variant of lz4 linking to liblz4 dynamic library

requires the dynamic library to expose static-only symbols (experimental API)

Example for #888

.travis.yml

@@ -33,9 +33,11 @@ matrix:
       script:
         - CC=clang MOREFLAGS=-fsanitize=address make -C tests test-frametest test-fuzzer
 
-    - name: Custom LZ4_DISTANCE_MAX
+    - name: Custom LZ4_DISTANCE_MAX ; Build lz4-wlib (CLI linked to dynamic library)
       script:
         - MOREFLAGS=-DLZ4_DISTANCE_MAX=8000 make check
+        - make clean
+        - make -C programs lz4-wlib
 
     - name: (Precise) g++ and clang CMake test
       dist: precise

lib/README.md

@@ -35,12 +35,13 @@ So it's necessary to include all `*.c` and `*.h` files present in `/lib`.
 
 Definitions which are not guaranteed to remain stable in future versions,
 are protected behind macros, such as `LZ4_STATIC_LINKING_ONLY`.
-As the name implies, these definitions can only be invoked
+As the name strongly implies, these definitions should only be invoked
 in the context of static linking ***only***.
 Otherwise, dependent application may fail on API or ABI break in the future.
-The associated symbols are also not present in dynamic library by default.
+The associated symbols are also not exposed by the dynamic library by default.
 Should they be nonetheless needed, it's possible to force their publication
-by using build macro `LZ4_PUBLISH_STATIC_FUNCTIONS`.
+by using build macros `LZ4_PUBLISH_STATIC_FUNCTIONS`
+and `LZ4F_PUBLISH_STATIC_FUNCTIONS`.
 
 
 #### Build macros

lib/lz4frame.h

@@ -381,7 +381,7 @@ LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeDecompressionContext(LZ4F_dctx* dctx);
  *  note : Frame header size is variable, but is guaranteed to be
  *         >= LZ4F_HEADER_SIZE_MIN bytes, and <= LZ4F_HEADER_SIZE_MAX bytes.
  */
-size_t LZ4F_headerSize(const void* src, size_t srcSize);
+LZ4FLIB_API size_t LZ4F_headerSize(const void* src, size_t srcSize);
 
 /*! LZ4F_getFrameInfo() :
  *  This function extracts frame parameters (max blockSize, dictID, etc.).
@@ -498,9 +498,9 @@ extern "C" {
  * Use at your own risk.
  */
 #ifdef LZ4F_PUBLISH_STATIC_FUNCTIONS
-#define LZ4FLIB_STATIC_API LZ4FLIB_API
+# define LZ4FLIB_STATIC_API LZ4FLIB_API
 #else
-#define LZ4FLIB_STATIC_API
+# define LZ4FLIB_STATIC_API
 #endif
 
 

ossfuzz/Makefile

@@ -47,6 +47,7 @@ FUZZERS := \
 	round_trip_frame_fuzzer \
 	decompress_frame_fuzzer
 
+.PHONY: all
 all: $(FUZZERS)
 
 # Include a rule to build the static library if calling this target
@@ -70,5 +71,8 @@ $(LZ4DIR)/liblz4.a:
 	$(RM) $*_fuzzer $*_fuzzer.o standaloneengine.o
 
 .PHONY: clean
-clean: compress_fuzzer_clean decompress_fuzzer_clean
+clean: compress_fuzzer_clean decompress_fuzzer_clean \
+	compress_frame_fuzzer_clean compress_hc_fuzzer_clean \
+	decompress_frame_fuzzer_clean round_trip_frame_fuzzer_clean \
+	round_trip_fuzzer_clean round_trip_hc_fuzzer_clean round_trip_stream_fuzzer_clean
 	$(MAKE) -C $(LZ4DIR) clean

programs/.gitignore

@@ -4,6 +4,7 @@ unlz4
 lz4cat
 lz4c
 lz4c32
+lz4-wlib
 datagen
 frametest
 frametest32

programs/Makefile

@@ -41,12 +41,13 @@ LIBVER_MINOR := $(shell echo $(LIBVER_MINOR_SCRIPT))
 LIBVER_PATCH := $(shell echo $(LIBVER_PATCH_SCRIPT))
 LIBVER   := $(shell echo $(LIBVER_SCRIPT))
 
-SRCFILES := $(sort $(wildcard $(LZ4DIR)/*.c) $(wildcard *.c))
+LIBFILES  = $(wildcard $(LZ4DIR)/*.c)
-OBJFILES := $(SRCFILES:.c=.o)
+SRCFILES  = $(sort $(LIBFILES) $(wildcard *.c))
+OBJFILES  = $(SRCFILES:.c=.o)
 
 CPPFLAGS += -I$(LZ4DIR) -DXXH_NAMESPACE=LZ4_
 CFLAGS   ?= -O3
-DEBUGFLAGS:=-Wall -Wextra -Wundef -Wcast-qual -Wcast-align -Wshadow \
+DEBUGFLAGS= -Wall -Wextra -Wundef -Wcast-qual -Wcast-align -Wshadow \
             -Wswitch-enum -Wdeclaration-after-statement -Wstrict-prototypes \
             -Wpointer-arith -Wstrict-aliasing=1
 CFLAGS   += $(DEBUGFLAGS) $(MOREFLAGS)
@@ -82,13 +83,25 @@ lz4: $(OBJFILES) lz4-exe.o
 	$(CC) $(FLAGS) $^ -o $@$(EXT)
 else
 lz4: $(OBJFILES)
-	$(CC) $(FLAGS) $^ -o $@$(EXT)
+	$(CC) $(FLAGS) $(OBJFILES) -o $@$(EXT) $(LDLIBS)
 endif
 
-
+.PHONY: lz4-release
 lz4-release: DEBUGFLAGS=
 lz4-release: lz4
 
+lz4-wlib: LIBFILES =
+lz4-wlib: SRCFILES+= $(LZ4DIR)/xxhash.c  # benchmark unit needs XXH64()
+lz4-wlib: LDFLAGS += -L $(LZ4DIR)
+lz4-wlib: LDLIBS   = -llz4
+lz4-wlib: liblz4 $(OBJFILES)
+	@echo WARNING: $@ must link to an extended variant of the dynamic library which also exposes unstable symbols
+	$(CC) $(FLAGS) $(OBJFILES) -o $@$(EXT) $(LDLIBS)
+
+.PHONY:liblz4
+liblz4:
+	CPPFLAGS="-DLZ4F_PUBLISH_STATIC_FUNCTIONS -DLZ4_PUBLISH_STATIC_FUNCTIONS" $(MAKE) -C $(LZ4DIR) liblz4
+
 lz4c: lz4
 	$(LN_SF) lz4$(EXT) lz4c$(EXT)
 
@@ -113,7 +126,8 @@ ifeq ($(WINBASED),yes)
 endif
 	@$(MAKE) -C $(LZ4DIR) $@ > $(VOID)
 	@$(RM) core *.o *.test tmp* \
-           lz4$(EXT) lz4c$(EXT) lz4c32$(EXT) unlz4$(EXT) lz4cat$(EXT)
+           lz4$(EXT) lz4c$(EXT) lz4c32$(EXT) lz4-wlib$(EXT) \
+           unlz4$(EXT) lz4cat$(EXT)
 	@echo Cleaning completed