Add fuzzers for consumption by https://github.com/google/oss-fuzz

.gitignore

@@ -1,3 +1,4 @@
 *.o
+*.a
 /woff2_compress
 /woff2_decompress

Makefile

@@ -2,10 +2,13 @@ OS := $(shell uname)
 
 CPPFLAGS = -I./brotli/dec/ -I./brotli/enc/ -I./src
 
+AR ?= ar
 CC ?= gcc
 CXX ?= g++
 
-COMMON_FLAGS = -fno-omit-frame-pointer -no-canonical-prefixes -DFONT_COMPRESSION_BIN -D __STDC_FORMAT_MACROS
+# It's helpful to be able to turn this off for fuzzing
+CANONICAL_PREFIXES ?= -no-canonical-prefixes
+COMMON_FLAGS = -fno-omit-frame-pointer $(CANONICAL_PREFIXES) -DFONT_COMPRESSION_BIN -D __STDC_FORMAT_MACROS
 
 ifeq ($(OS), Darwin)
   CPPFLAGS += -DOS_MACOSX
@@ -13,6 +16,7 @@ else
   COMMON_FLAGS += -fno-tree-vrp
 endif
 
+ARFLAGS = crf
 CFLAGS += $(COMMON_FLAGS)
 CXXFLAGS += $(COMMON_FLAGS) -std=c++11
 
@@ -28,14 +32,18 @@ DECOBJ = $(BROTLI)/dec/*.o
 
 OBJS = $(patsubst %, $(SRCDIR)/%, $(OUROBJ))
 EXECUTABLES=woff2_compress woff2_decompress
-
 EXE_OBJS=$(patsubst %, $(SRCDIR)/%.o, $(EXECUTABLES))
+ARCHIVES=convert_woff2ttf_fuzzer convert_woff2ttf_fuzzer_new_entry
+ARCHIVE_OBJS=$(patsubst %, $(SRCDIR)/%.o, $(ARCHIVES))
 
 ifeq (,$(wildcard $(BROTLI)/*))
   $(error Brotli dependency not found : you must initialize the Git submodule)
 endif
 
-all : $(OBJS) $(EXECUTABLES)
+all : $(OBJS) $(EXECUTABLES) $(ARCHIVES)
+
+$(ARCHIVES) : $(ARCHIVE_OBJS) $(OBJS) deps
+	$(AR) $(ARFLAGS) $(SRCDIR)/$@.a $(OBJS) $(ENCOBJ) $(DECOBJ) $(SRCDIR)/$@.o
 
 $(EXECUTABLES) : $(EXE_OBJS) deps
 	$(CXX) $(LFLAGS) $(OBJS) $(ENCOBJ) $(DECOBJ) $(SRCDIR)/$@.o -o $@
@@ -45,6 +53,6 @@ deps :
 	$(MAKE) -C $(BROTLI)/enc
 
 clean :
-	rm -f $(OBJS) $(EXE_OBJS) $(EXECUTABLES)
+	rm -f $(OBJS) $(EXE_OBJS) $(EXECUTABLES) $(ARCHIVE_OBJS)
 	$(MAKE) -C $(BROTLI)/dec clean
 	$(MAKE) -C $(BROTLI)/enc clean

src/convert_woff2ttf_fuzzer.cc

@@ -0,0 +1,13 @@
+#include <stddef.h>
+#include <stdint.h>
+
+#include "woff2_dec.h"
+
+// Entry point for LibFuzzer.
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  std::string buf;
+  woff2::WOFF2StringOut out(&buf);
+  out.SetMaxSize(30 * 1024 * 1024);
+  woff2::ConvertWOFF2ToTTF(data, size, &out);
+  return 0;
+}

src/convert_woff2ttf_fuzzer_new_entry.cc

@@ -0,0 +1,12 @@
+#include <string>
+#include "woff2_dec.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t data_size) {
+  // Decode using newer entry pattern.
+  // Same pattern as woff2_decompress.
+  std::string output(std::min(woff2::ComputeWOFF2FinalSize(data, data_size),
+                              woff2::kDefaultMaxSize), 0);
+  woff2::WOFF2StringOut out(&output);
+  woff2::ConvertWOFF2ToTTF(data, data_size, &out);
+  return 0;
+}