diff options
| -rw-r--r-- | 04_dynld_nostd/libgreet.c | 10 | ||||
| -rw-r--r-- | 04_dynld_nostd/main.c | 5 |
2 files changed, 10 insertions, 5 deletions
diff --git a/04_dynld_nostd/libgreet.c b/04_dynld_nostd/libgreet.c index e697690..f90bdbf 100644 --- a/04_dynld_nostd/libgreet.c +++ b/04_dynld_nostd/libgreet.c @@ -5,19 +5,25 @@ int gCalled = 0; const char* get_greet() { + // Reference global variable -> generates RELA relocation (R_X86_64_GLOB_DAT). ++gCalled; return "Hello from libgreet.so!"; } const char* get_greet2() { + // Reference global variable -> generates RELA relocation (R_X86_64_GLOB_DAT). ++gCalled; return "Hello 2 from libgreet.so!"; } -__attribute__((constructor)) static void libinit() { /* static -> generates R_X86_64_RELATIVE relocation */ +// Definition of `static` function which is referenced from the `INIT` dynamic +// section entry -> generates R_X86_64_RELATIVE relocation. +__attribute__((constructor)) static void libinit() { pfmt("libgreet.so: libinit\n"); } -__attribute__((destructor)) void libfini() { /* non static -> generates R_X86_64_64 relocation */ +// Definition of `non static` function which is referenced from the `FINI` +// dynamic section entry -> generates R_X86_64_64 relocation. +__attribute__((destructor)) void libfini() { pfmt("libgreet.so: libfini\n"); } diff --git a/04_dynld_nostd/main.c b/04_dynld_nostd/main.c index 709fad0..6efa5fc 100644 --- a/04_dynld_nostd/main.c +++ b/04_dynld_nostd/main.c @@ -1,7 +1,6 @@ // Copyright (c) 2020 Johannes Stoelp #include <io.h> -#include <syscalls.h> // API of `libgreet.so`. extern const char* get_greet(); @@ -11,10 +10,10 @@ extern int gCalled; void _start() { pfmt("Running _start() @ %s\n", __FILE__); - // Call function from libgreet.so -> generates PLT relocations. + // Call function from libgreet.so -> generates PLT relocations (R_X86_64_JUMP_SLOT). pfmt("get_greet() -> %s\n", get_greet()); pfmt("get_greet2() -> %s\n", get_greet2()); - // Reference global variable from libgreet.so -> generates RELA relocation. + // Reference global variable from libgreet.so -> generates RELA relocation (R_X86_64_COPY). pfmt("libgreet.so called %d times\n", gCalled); } |