testing/test-cases/dlsym-in-interposed-malloc.dtest/interposer.c

   1
   2 #include <dlfcn.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <mach-o/dyld-interposing.h>
   7
   8 static bool inMalloc = false;
   9 static bool forceSystemMalloc = false;
  10
  11 void* mymalloc(size_t size)
  12 {
  13     // We are in our own printf, so we need to fall back to the default malloc
  14     if (forceSystemMalloc) {
  15         return malloc(size);
  16     }
  17
  18     if (inMalloc) {
  19         // Recursion!   This shouldn't happen.
  20         forceSystemMalloc = true;
  21         printf("[FAIL] dlsym-in-interposed-malloc mymalloc() is recursive\n");
  22         exit(1);
  23     }
  24
  25     inMalloc = true;
  26
  27     // ASan calls dlsym before libdyld has created an image list.  Make sure that succeeds
  28     void* sym = dlsym(RTLD_DEFAULT, "malloc");
  29     if (sym == NULL) {
  30         forceSystemMalloc = true;
  31         printf("[FAIL] dlsym-in-interposed-malloc dlsym failed\n");
  32         exit(1);
  33     }
  34
  35     if (sym != mymalloc) {
  36         forceSystemMalloc = true;
  37         printf("[FAIL] dlsym-in-interposed-malloc dlsym result %p != mymalloc %p\n", sym, &mymalloc);
  38         exit(1);
  39     }
  40     void* result = malloc(size);
  41
  42     inMalloc = false;
  43
  44     return result;
  45 }
  46
  47 DYLD_INTERPOSE(mymalloc, malloc)