invokevirtual: get the actual class at run-time

[mate.git] / ffi / trap.c

diff --git a/ffi/trap.c b/ffi/trap.c
index 0a766094351c10a19affd234a859497882caff05..228b2c36f3e96d1122f9b7ec74ed631ca2d8b5c3 100644 (file)
--- a/ffi/trap.c
+++ b/ffi/trap.c
@@ -19,7 +19,7 @@
 
 #include <sys/ucontext.h>
 
-unsigned int getMethodEntry(unsigned int, void *, void *);
+unsigned int getMethodEntry(unsigned int, unsigned int);
 unsigned int getStaticFieldAddr(unsigned int, void*);
 
 #define NEW_MAP(prefix) \
@@ -38,6 +38,7 @@ unsigned int getStaticFieldAddr(unsigned int, void*);
 NEW_MAP(method)
 NEW_MAP(trap)
 NEW_MAP(class)
+NEW_MAP(virtual)
 
 
 void mainresult(unsigned int a)
@@ -55,7 +56,7 @@ void callertrap(int nSignal, siginfo_t *info, void *ctx)
                printf("callertrap: something is wrong here. abort\n");
                exit(0);
        }
-       unsigned int patchme = getMethodEntry(from, method_map, trap_map);
+       unsigned int patchme = getMethodEntry(from, 0);
 
        unsigned char *insn = (unsigned char *) from;
        *insn = 0xe8; // call opcode
@@ -71,18 +72,21 @@ void staticfieldtrap(int nSignal, siginfo_t *info, void *ctx)
        /* TODO(bernhard): more generic and cleaner please... */
        mcontext_t *mctx = &((ucontext_t *) ctx)->uc_mcontext;
        unsigned int from = (unsigned int) mctx->gregs[REG_EIP];
-       if (from == 0) { // invokevirtual
-               unsigned int eax = (unsigned int) mctx->gregs[REG_EAX];
+       if (from < 0x10000) { // invokevirtual
+               if (from > 0) {
+                       printf("from: 0x%08x but should be 0 :-(\n", from);
+               }
+               unsigned int method_table_ptr = (unsigned int) mctx->gregs[REG_EAX];
                unsigned int *esp = (unsigned int *) mctx->gregs[REG_ESP];
                /* get actual eip from stack storage */
                unsigned int from = (*esp) - 3;
                unsigned char offset = *((unsigned char *) (*esp) - 1);
                /* method entry to patch */
-               unsigned int *to_patch = (unsigned int*) (eax + offset);
+               unsigned int *to_patch = (unsigned int*) (method_table_ptr + offset);
                printf("invokevirtual by 0x%08x with offset 0x%08x\n", from, offset);
                printf(" to_patch: 0x%08x\n", (unsigned int) to_patch);
                printf("*to_patch: 0x%08x\n", *to_patch);
-               *to_patch = getMethodEntry(from, method_map, trap_map);
+               *to_patch = getMethodEntry(from, method_table_ptr);
                mctx->gregs[REG_EIP] = *to_patch;
                printf("*to_patch: 0x%08x\n", *to_patch);
        } else {