CMake: build fuzzers in standalone mode as part of BUILD_TESTING

Author: rouault

test/CMakeLists.txt

@@ -108,3 +108,8 @@ proj_add_gie_test("GIGS-5208" "gigs/5208.gie")
 add_subdirectory(cli)
 add_subdirectory(unit)
 add_subdirectory(benchmark)
+if (EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/fuzzers")
+  add_subdirectory(fuzzers)
+endif()
+
+

test/fuzzers/CMakeLists.txt

@@ -0,0 +1,8 @@
+if(NOT WIN32)
+
+  add_compile_options(${PROJ_CXX_WARN_FLAGS})
+
+  add_executable(proj_crs_to_crs_fuzzer proj_crs_to_crs_fuzzer.cpp)
+  target_compile_definitions(proj_crs_to_crs_fuzzer PRIVATE -DSTANDALONE)
+  target_link_libraries(proj_crs_to_crs_fuzzer PRIVATE ${PROJ_LIBRARIES})
+endif()

test/fuzzers/README.TXT

@@ -8,12 +8,11 @@ and call scripts in this directory.
 The list of issues is in:
 https://bugs.chromium.org/p/oss-fuzz/issues/list?q=proj4
 
-- Build standard_fuzzer in a standalone mode:
-
-    $ g++ -g -std=c++11 standard_fuzzer.cpp -o standard_fuzzer -fvisibility=hidden -DSTANDALONE ../../build/lib/libproj.a -lpthread -lsqlite3 -I../../src -I../../include
+- Build proj_crs_to_crs_fuzzer in a standalone mode with the
+  -DBUILD_TESTING=ON CMake options
 
   Run it:
-    $ PROJ_DATA=../../data ./standard_fuzzer {file_generated_by_oss_fuzz}
+    $ bin/proj_crs_to_crs_fuzzer {file_generated_by_oss_fuzz}
 
 - Run locally OSS Fuzz:
     $ git clone https://github.com/google/oss-fuzz.git
@@ -24,8 +23,8 @@ https://bugs.chromium.org/p/oss-fuzz/issues/list?q=proj4
   Build fuzzers with the address sanitizer (could use undefined, etc...)
     $ python infra/helper.py build_fuzzers --sanitizer address $PROJECT_NAME
 
-  Test a particular fuzzer (replace standard_fuzzer by other fuzzers)
-    $ python infra/helper.py run_fuzzer $PROJECT_NAME standard_fuzzer
+  Test a particular fuzzer (replace proj_crs_to_crs_fuzzer by other fuzzers)
+    $ python infra/helper.py run_fuzzer $PROJECT_NAME proj_crs_to_crs_fuzzer
 
 
 How to deal with issues reported in https://bugs.chromium.org/p/oss-fuzz/issues/list?q=proj4 ?

test/fuzzers/proj_crs_to_crs_fuzzer.cpp

@@ -124,7 +124,12 @@ int main(int argc, char *argv[]) {
             fclose(f);
             exit(1);
         }
-        fread(buf, nLen, 1, f);
+        if (fread(buf, nLen, 1, f) != 1) {
+            fprintf(stderr, "fread failed.\n");
+            fclose(f);
+            free(buf);
+            exit(1);
+        }
         fclose(f);
         nRet = LLVMFuzzerTestOneInput((const uint8_t *)(buf), nLen);
         free(buf);