Add on_fns symbol to magic.s

MyNameIsTrez · Sep 13, 2024 · 911d3f5 · 911d3f5
1 parent 88c7394
commit 911d3f5
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Showing 2 changed files with 17 additions and 20 deletions.
diff --git a/magic.s b/magic.s
@@ -1,5 +1,15 @@
+// Assemble: clang magic.s --target=arm64 -shared
+
+.data
+
+.global _on_fns
+on_fns:
+    .xword _magic
+
+.text
+
 .global _magic
 .balign 16
 _magic:
-    mov X0, 42
+    mov w0, 42
     ret
diff --git a/main.c b/main.c
@@ -2,35 +2,22 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-// struct magic_on_fns {
-//     int (*magic)(void);
-// };
+struct magic_on_fns {
+    int (*magic)(void);
+};
 
-// nasm -fmacho64 magic.s -o magic.dylib
-// clang main.c && ./a.out
-// xxd magic.dylib
-// llvm-readelf magic.dylib
-// llvm-objdump -D magic.dylib
 int main(void) {
     void *l = dlopen("./magic.dylib", RTLD_NOW);
     if (l == NULL) {
         printf("dlopen failed: %s\n", dlerror());
         return EXIT_FAILURE;
     }
 
-    int (*magic)(void) = dlsym(l, "magic");
-    if (magic == NULL) {
+    void *on_fns = dlsym(l, "on_fns");
+    if (on_fns == NULL) {
         printf("dlsym failed: %s\n", dlerror());
         return EXIT_FAILURE;
     }
 
-    printf("magic: %d\n", magic());
-
-    // void *on_fns = dlsym(l, "on_fns");
-    // if (on_fns == NULL) {
-    //     printf("dlsym failed: %s\n", dlerror());
-    //     return EXIT_FAILURE;
-    // }
-
-    // printf("magic: %d\n", ((struct magic_on_fns *)on_fns)->magic());
+    printf("magic: %d\n", ((struct magic_on_fns *)on_fns)->magic());
 }