diff options
Diffstat (limited to 'src/actual.h')
-rw-r--r-- | src/actual.h | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/src/actual.h b/src/actual.h new file mode 100644 index 0000000..af64ec3 --- /dev/null +++ b/src/actual.h @@ -0,0 +1,60 @@ +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif + +#ifndef CHANGE_SRC_ACTUAL_FUNCTION_H_ +#define CHANGE_SRC_ACTUAL_FUNCTION_H_ + +#include <dlfcn.h> +#include <sys/mman.h> +#include <sys/uio.h> + +#include <memory> +#include <cstring> + +namespace { + template <class Result, typename... Arguments> + using function_ptr = Result(*)(Arguments...); + + template <typename FunctionPtr> + FunctionPtr get_actual_function(const std::string& symbol_name) { + const void* symbol_address{ dlsym(RTLD_NEXT, symbol_name.c_str()) }; + + FunctionPtr actual_function{}; + std::memcpy(&actual_function, &symbol_address, sizeof(symbol_address)); + + return actual_function; + } +} + +namespace actual { + static auto write = get_actual_function< + function_ptr<ssize_t, int, const void*, size_t> + >("write"); + + static auto writev = get_actual_function< + function_ptr<ssize_t, int, const iovec*, int> + >("writev"); + + static auto rename = get_actual_function< + function_ptr<int, const char*, const char*> + >("rename"); + + static auto rmdir = get_actual_function< + function_ptr<int, const char*> + >("rmdir"); + + static auto unlink = get_actual_function< + function_ptr<int, const char*> + >("unlink"); + + static auto unlinkat = get_actual_function< + function_ptr<int, int, const char*, int> + >("unlinkat"); + + static auto mmap = get_actual_function< + function_ptr<void*, void*, size_t, int, int, int, off_t> + >("mmap"); +} + +#endif // CHANGE_SRC_ACTUAL_FUNCTION_H_ |