Coverage: Do not print messages from gcov

We need to ignore messages from gcov. All those messages
start with profiling: and are printed using vfprintf(), so
the only thing we can do is add a library overriding those
functions and linking apt-pkg to it.

apt-pkg/CMakeLists.txt

@@ -49,3 +49,7 @@ add_version_script(apt-pkg)
 install(TARGETS apt-pkg LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})
 install(FILES ${headers} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/apt-pkg)
 flatify(${PROJECT_BINARY_DIR}/include/apt-pkg/ "${headers}")
+
+if(CMAKE_BUILD_TYPE STREQUAL "Coverage")
+  target_link_libraries(apt-pkg PUBLIC noprofile)
+endif()

test/interactive-helper/CMakeLists.txt

@@ -8,3 +8,6 @@ add_executable(aptwebserver aptwebserver.cc)
 target_link_libraries(aptwebserver apt-pkg  ${CMAKE_THREAD_LIBS_INIT})
 add_executable(test_fileutl test_fileutl.cc)
 target_link_libraries(test_fileutl apt-pkg)
+
+add_library(noprofile SHARED libnoprofile.c)
+target_link_libraries(noprofile ${CMAKE_DL_LIBS})

test/interactive-helper/libnoprofile.c

@@ -0,0 +1,50 @@
+#define _GNU_SOURCE
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dlfcn.h>
+#include <unistd.h>
+#include <stdio.h>
+
+int vprintf(const char *format, va_list ap) {
+	static int (*func_fprintf)(const char *format, va_list ap) = NULL;
+	if (func_fprintf == NULL)
+		func_fprintf = (int (*) (const char *format, va_list ap)) dlsym(RTLD_NEXT, "vprintf");
+
+    va_list ap2;
+    va_copy(ap2, ap);
+    if (strncmp(format, "profiling:", strlen("profiling:")) == 0)
+        return 0;
+    int res = func_fprintf(format, ap2);
+    va_end(ap2);
+    return res;
+}
+int printf(const char *format, ...) {
+    va_list ap;
+    va_start(ap, format);
+    int res = vprintf(format, ap);
+    va_end(ap);
+    return res;
+}
+
+int vfprintf(FILE *stream, const char *format, va_list ap) {
+	static int (*func_vfprintf)(FILE *stream, const char *format, va_list ap) = NULL;
+	if (func_vfprintf == NULL)
+		func_vfprintf = (int (*) (FILE *stream, const char *format, va_list ap)) dlsym(RTLD_NEXT, "vfprintf");
+
+    va_list ap2;
+    va_copy(ap2, ap);
+    if (strncmp(format, "profiling:", strlen("profiling:")) == 0)
+        return 0;
+    int res = func_vfprintf(stream, format, ap2);
+    va_end(ap2);
+    return res;
+}
+
+int fprintf(FILE *stream, const char *format, ...) {
+    va_list ap;
+    va_start(ap, format);
+    int res = vfprintf(stream, format, ap);
+    va_end(ap);
+    return res;
+}