diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | CMakeLists.txt | 35 | ||||
| -rw-r--r-- | defines.h | 11 | ||||
| -rw-r--r-- | print.c | 9 | ||||
| -rw-r--r-- | print.h | 6 | ||||
| -rw-r--r-- | shim.c | 27 | ||||
| -rw-r--r-- | wrap.c | 19 | ||||
| -rw-r--r-- | wrap.h | 21 |
8 files changed, 129 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..378eac2 --- /dev/null +++ b/.gitignore @@ -0,0 +1 @@ +build diff --git a/CMakeLists.txt b/CMakeLists.txt new file mode 100644 index 0000000..a7dd4ed --- /dev/null +++ b/CMakeLists.txt @@ -0,0 +1,35 @@ +cmake_minimum_required(VERSION 3.10) + +set(CFLAGS + -Wall -Wextra -Wfloat-equal + -Wstrict-overflow=5 -Wunreachable-code + -Wundef -Wcast-qual -Wconversion + -Wswitch-default -Wmissing-include-dirs + -Wshadow -Wstrict-aliasing -Winit-self + -Wcast-align -Wpointer-arith + -Wno-unused-parameter -Wuninitialized + -D_GNU_SOURCE +) + +list(APPEND + SOURCES + ${CMAKE_CURRENT_SOURCE_DIR}/print.c + ${CMAKE_CURRENT_SOURCE_DIR}/print.h + ${CMAKE_CURRENT_SOURCE_DIR}/shim.c + ${CMAKE_CURRENT_SOURCE_DIR}/wrap.c + ${CMAKE_CURRENT_SOURCE_DIR}/wrap.h +) + +project(shim) +add_library(shim_objects OBJECT ${SOURCES}) +set_property(TARGET shim_objects PROPERTY POSITION_INDEPENDENT_CODE ON) +set_property(TARGET shim_objects PROPERTY C_VISIBILITY_PRESET hidden) +set_property(TARGET shim_objects PROPERTY VISIBILITY_INLINES_HIDDEN ON) +target_compile_options(shim_objects PUBLIC ${CFLAGS}) + +add_library(shim SHARED $<TARGET_OBJECTS:shim_objects>) +target_link_libraries(shim LINK_PUBLIC ${CMAKE_DL_LIBS}) + +add_library(shim_static STATIC $<TARGET_OBJECTS:shim_objects>) + + diff --git a/defines.h b/defines.h new file mode 100644 index 0000000..6c04a4e --- /dev/null +++ b/defines.h @@ -0,0 +1,11 @@ +#ifndef DEFINES_H +#define DEFINES_H + +#ifndef NDEBUG +#define DEBUG +#endif + +#define STR(x) #x +#define XSTR(x) STR(x) + +#endif /* DEFINES_H */ @@ -0,0 +1,9 @@ +#include <string.h> +#include <unistd.h> + +#include "print.h" + +void print(const char* str, ...) +{ + write(STDOUT_FILENO, str, strlen(str)); +} @@ -0,0 +1,6 @@ +#ifndef PRINT_H +#define PRINT_H + +void print(const char* str, ...); + +#endif
\ No newline at end of file @@ -0,0 +1,27 @@ +#include <stdlib.h> + +#include "print.h" +#include "wrap.h" + +#pragma GCC visibility push(default) + +void* malloc(size_t size) { + return REAL(malloc)(size); +} + +void free(void* ptr) +{ + return REAL(free)(ptr); +} + +void* calloc(size_t nmemb, size_t size) +{ + return REAL(calloc)(nmemb, size); +} + +void* realloc(void *ptr, size_t size) +{ + return REAL(realloc)(ptr, size); +} + +#pragma GCC visibility pop @@ -0,0 +1,19 @@ +#include <stddef.h> + +#include "wrap.h" + +void *(*_REAL(malloc))(size_t size) = NULL; +void (*_REAL(free))(void *ptr) = NULL; +void *(*_REAL(calloc))(size_t nmemb, size_t size) = NULL; +void *(*_REAL(realloc))(void *ptr, size_t size) = NULL; + +#ifdef __GNUC__ +void __attribute__((constructor)) __wrap_init() +{ + // set the real values up as soon as possible + REAL(malloc); + REAL(free); + REAL(calloc); + REAL(realloc); +} +#endif @@ -0,0 +1,21 @@ +#ifndef WRAP_H +#define WRAP_H + +#include <dlfcn.h> + +#include "defines.h" + +#define _REAL(n) __real_##n +#define REAL(n) \ + ({ \ + if (!_REAL(n)) \ + _REAL(n) = dlsym(RTLD_NEXT, XSTR(n)); \ + _REAL(n); \ + }) + +extern void *(*_REAL(malloc))(size_t size); +extern void (*_REAL(free))(void *ptr); +extern void *(*_REAL(calloc))(size_t nmemb, size_t size); +extern void *(*_REAL(realloc))(void *ptr, size_t size); + +#endif /* WRAP_H */ |