CMake: Add sigaction, sigaltstack, self dbg

cmake/FindSelfDbg.cmake

@@ -0,0 +1,37 @@
+include(CheckCXXSourceCompiles)
+
+check_cxx_source_compiles("
+    #include <unistd.h>
+    #include <sys/stat.h>
+    #include <fcntl.h>
+    #include <sys/syscall.h>
+    #include <sys/types.h>
+    #include <sys/wait.h>
+    int main() {
+        pid_t tid = syscall(SYS_gettid);
+        int status;
+        waitpid((pid_t) 0, &status, 0);
+        return WIFEXITED(status) && WEXITSTATUS(status);
+    }"
+    DBG_GDB_FOUND
+)
+
+if (DBG_GDB_FOUND)
+    add_compile_options(
+        -DWITH_DBG_GDB
+    )
+endif (DBG_GDB_FOUND)
+
+check_cxx_source_compiles("
+    #include <sys/prctl.h>
+    int main() {
+        return prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
+    }"
+    PRCTL_PT_FOUND
+)
+
+if (PRCTL_PT_FOUND)
+    add_compile_options(
+        -DWITH_PRCTL_PT
+    )
+endif (PRCTL_PT_FOUND)