testing/test-cases/dyld_shared_cache_some_image_overridden.dtest/main.c

   1
   2 // BUILD:  $CC myzlib.c -dynamiclib -o $BUILD_DIR/override/libz.1.dylib -install_name /usr/lib/libz.1.dylib -compatibility_version 1.0
   3 // BUILD:  $CC main.c  -o $BUILD_DIR/dyld_shared_cache_some_image_overridden.exe -lz
   4 // BUILD:  $DYLD_ENV_VARS_ENABLE $BUILD_DIR/dyld_shared_cache_some_image_overridden.exe
   5 // BUILD:  $CC main.c  -o $BUILD_DIR/dyld_shared_cache_some_image_overridden-no-lz.exe -DNO_LZ
   6 // BUILD:  $DYLD_ENV_VARS_ENABLE $BUILD_DIR/dyld_shared_cache_some_image_overridden-no-lz.exe
   7
   8 // RUN:  ./dyld_shared_cache_some_image_overridden.exe
   9 // RUN:  DYLD_LIBRARY_PATH=$RUN_DIR/override/ ./dyld_shared_cache_some_image_overridden.exe
  10 // RUN:  ./dyld_shared_cache_some_image_overridden-no-lz.exe
  11 // RUN:  DYLD_LIBRARY_PATH=$RUN_DIR/override/ ./dyld_shared_cache_some_image_overridden-no-lz.exe
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <zlib.h>
  17 #include <stdbool.h>
  18
  19 #include <dlfcn.h>
  20 #include <mach-o/dyld_priv.h>
  21
  22 #include "test_support.h"
  23
  24 // The test here is to override libz.1.dylib which is in the dyld cache with our own implementation.
  25 // We then ensure that dyld_shared_cache_some_image_overridden returns the correct value to match whether we took a root
  26
  27 extern const char* zlibVersion();
  28
  29 int main(int argc, const char* argv[], const char* envp[], const char* apple[]) {
  30     // If we aren't using a shared cache, eg, have DYLD_SHARED_REGION=avoid, then just assume we work
  31     uuid_t currentCacheUUID;
  32     if ( !_dyld_get_shared_cache_uuid(currentCacheUUID) ) {
  33         if (dyld_shared_cache_some_image_overridden())
  34             FAIL("Overriden but no shared cache ");
  35         else
  36             PASS("No shared cache");
  37     }
  38
  39 #if NO_LZ
  40     // This run doesn't link lz so instead dlopen's it
  41     bool expectMyDylib = (getenv("DYLD_LIBRARY_PATH") != NULL);
  42
  43     void* handle = dlopen("/usr/lib/libz.1.dylib", RTLD_NOLOAD);
  44     if ( handle != NULL ) {
  45         // Uh oh.  Someone else has started linking libz so we can't use it as our root any more
  46         FAIL("libz is hard linked now.  Update test to use a new dylib");
  47     }
  48
  49     bool launchedWithOverriddenBinary = dyld_shared_cache_some_image_overridden();
  50
  51     // Now dlopen libz
  52     handle = dlopen("/usr/lib/libz.1.dylib", RTLD_LAZY);
  53     if ( handle == NULL ) {
  54         FAIL("/usr/lib/libz.1.dylib could not be loaded, %s", dlerror());
  55     }
  56
  57     // verify handle has the version symbol
  58     __typeof(&zlibVersion) versionSymbol = (__typeof(&zlibVersion))dlsym(handle, "zlibVersion");
  59     if ( versionSymbol == NULL ) {
  60         FAIL("zlibVersion was not found");
  61     }
  62
  63     bool usingMyDylib = (strcmp(versionSymbol(), "my") == 0);
  64
  65     if ( usingMyDylib != expectMyDylib ) {
  66         // Not using the right dylib
  67         FAIL("%s", expectMyDylib ? "my" : "os");
  68     }
  69
  70     // Using the right dylib, so now see if we returned the correct value for dyld_shared_cache_some_image_overridden
  71     if (usingMyDylib) {
  72         if (!dyld_shared_cache_some_image_overridden()) {
  73             FAIL("My dylib but not some dylib overridden");
  74         }
  75     } else if (!launchedWithOverriddenBinary) {
  76         // We didn't have a root when we launched, so now we can make sure we do have a root after the dlopen
  77         // Assume we aren't testing against a root of libz in the system itself...
  78         if (dyld_shared_cache_some_image_overridden()) {
  79             FAIL("System dylib was overridden");
  80         }
  81     } else {
  82         // We can't actually be sure of the result here.  There may be other roots on the system so call the API to
  83         // make sure it doesn't crash, but don't actually check it.
  84         dyld_shared_cache_some_image_overridden();
  85     }
  86 #else
  87     // This run links libz directly
  88     bool expectMyDylib = (getenv("DYLD_LIBRARY_PATH") != NULL);
  89
  90     bool usingMyDylib = (strcmp(zlibVersion(), "my") == 0);
  91
  92     if ( usingMyDylib != expectMyDylib ) {
  93         // Not using the right dylib
  94         FAIL("%s", expectMyDylib ? "my" : "os");
  95     }
  96
  97     // Using the right dylib, so now see if we returned the correct value for dyld_shared_cache_some_image_overridden
  98     if (usingMyDylib) {
  99         if (!dyld_shared_cache_some_image_overridden()) {
 100             FAIL("My dylib but not some dylib overridden");
 101         }
 102     } else {
 103         // We can't actually be sure of the result here.  There may be other roots on the system so call the API to
 104         // make sure it doesn't crash, but don't actually check it.
 105         dyld_shared_cache_some_image_overridden();
 106     }
 107 #endif
 108     PASS("%s", expectMyDylib ? "my" : "os");
 109
 110     return 0;
 111 }
 112