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Diffstat (limited to 'src/usertestelf.c')
-rw-r--r--src/usertestelf.c69
1 files changed, 0 insertions, 69 deletions
diff --git a/src/usertestelf.c b/src/usertestelf.c
deleted file mode 100644
index 1cbfcc5..0000000
--- a/src/usertestelf.c
+++ /dev/null
@@ -1,69 +0,0 @@
-#include <shared/printf.h>
-#include <user/lib/elf.h>
-#include <user/lib/syscall.c>
-
-const char *str = "Hello!\n", *str2 = "World.\n";
-
-__attribute__((visibility("hidden")))
-extern struct Elf64_Dyn _DYNAMIC[];
-
-__attribute__((visibility("hidden")))
-extern char _image_base[];
-
-static void printf_backend(void *arg, const char *buf, size_t len) {
- (void)arg;
- _syscall_write(1, buf, len, -1);
- _syscall_debug_klog(buf, len);
-}
-
-int printf(const char *fmt, ...) {
- int ret = 0;
- va_list argp;
- va_start(argp, fmt);
- ret = __printf_internal(fmt, argp, printf_backend, 0);
- va_end(argp);
- return ret;
-}
-
-
-static struct Elf64_Dyn *dyn_gettag(Elf64_Xword tag) {
- for (size_t i = 0;; i++) {
- if (_DYNAMIC[i].d_tag == tag) return &_DYNAMIC[i];
- if (_DYNAMIC[i].d_tag == DT_NULL) return NULL;
- }
-}
-
-static void reloc(void) {
- // TODO DT_REL
- if (dyn_gettag(DT_PLTGOT) || dyn_gettag(DT_JMPREL)) {
- printf("elf: unimplemented tag in _DYNAMIC\n");
- }
-
- struct Elf64_Dyn *rela_tag = dyn_gettag(DT_RELA);
- if (rela_tag) {
- /* not checking pointer validity,
- * crashing on an invalid elf is fine */
- size_t relasz = dyn_gettag(DT_RELASZ)->d_val;
- size_t relaent = dyn_gettag(DT_RELAENT)->d_val;
- for (size_t o = 0; o < relasz; o += relaent) {
- struct Elf64_Rela *r = (void*)_image_base + rela_tag->d_ptr + o;
- uintptr_t *target = (void*)_image_base + r->r_offset;
-
- switch (ELF64_R_TYPE(r->r_info)) {
- case R_X86_64_RELATIVE:
- *target = (uintptr_t)&_image_base + r->r_addend;
- break;
- default:
- printf("elf: unsupported relocation type\n");
- }
- }
- }
-}
-
-int main(void) {
- printf("loaded at %x\n", &_image_base);
- reloc();
- printf(str);
- printf(str2);
- _syscall_exit(0);
-}