fuzz: Get rid of cpp mess in fuzzers

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

tests/fuzz/CMakeLists.txt

@@ -1,7 +1,7 @@
 project(fuzzing CXX)
 
 macro(fuzzer name)
-    add_executable(${name} ${name}.cpp)
+    add_executable(${name} ${name}.c)
     target_link_libraries(${name}
                           PRIVATE
                               ssh::static)

tests/fuzz/ssh_bind_config_fuzzer.c

@@ -14,8 +14,6 @@
  * limitations under the License.
  */
 
-extern "C" {
-
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -52,5 +50,3 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 
     return 0;
 }
-
-}

tests/fuzz/ssh_client_config_fuzzer.c

@@ -14,8 +14,6 @@
  * limitations under the License.
  */
 
-extern "C" {
-
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -51,5 +49,3 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 
     return 0;
 }
-
-}

tests/fuzz/ssh_client_fuzzer.c

@@ -18,6 +18,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <signal.h>
+#include <stdbool.h>
 
 #define LIBSSH_STATIC 1
 #include <libssh/libssh.h>
@@ -83,7 +84,7 @@ static void select_loop(ssh_session session, ssh_channel channel)
     ssh_event_free(event);
 }
 
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
     ssh_session session = NULL;
     ssh_channel channel = NULL;

tests/fuzz/ssh_server_fuzzer.c

@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <sys/socket.h>
 #include <unistd.h>
+#include <stdbool.h>
 
 #define LIBSSH_STATIC 1
 #include <libssh/libssh.h>
@@ -117,7 +118,7 @@ static int write_rsa_hostkey(const char *rsakey_path)
     return 0;
 }
 
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
     int socket_fds[2] = {-1, -1};
     ssize_t nwritten;