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authorUlrich Drepper <drepper@redhat.com>2000-10-21 07:16:18 +0000
committerUlrich Drepper <drepper@redhat.com>2000-10-21 07:16:18 +0000
commitd785c366924df522974f4ee88d77fd8aaed58803 (patch)
tree12b41ae0e43531a39697176a6f7e71476262587e /elf
parentc91bc73e3e463ae6a80e548b899703efae256090 (diff)
downloadglibc-d785c366924df522974f4ee88d77fd8aaed58803.tar.gz
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Update.
2000-10-21  Ulrich Drepper  <drepper@redhat.com>

	* elf/dl-open.c (add_to_global): New function.  Split out from
	dl_open_worker.
	(dl_open_worker): Call add_to_global not only for new objects, also for
	previously loaded objects when (mode & RTLD_GLOBAL) and the object
	was not yet in the global scope.
	* elf/Makefile: Add rules to build and run lateglobal.
	* elf/lateglobal.c: New file.
	* elf/ltglobmod1.c: New file.
	* elf/ltglobmod2.c: New file.
Diffstat (limited to 'elf')
-rw-r--r--elf/Makefile11
-rw-r--r--elf/dl-open.c166
-rw-r--r--elf/lateglobal.c47
-rw-r--r--elf/ltglobmod1.c5
-rw-r--r--elf/ltglobmod2.c32
5 files changed, 183 insertions, 78 deletions
diff --git a/elf/Makefile b/elf/Makefile
index 033b0dcce9..06ff79d30a 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -55,7 +55,7 @@ distribute	:= $(rtld-routines:=.c) dynamic-link.h do-rel.h dl-machine.h \
 		   reldepmod1.c reldepmod2.c reldepmod3.c reldepmod4.c \
 		   nextmod1.c nextmod2.c \
 		   neededobj1.c neededobj2.c neededobj3.c \
-		   unload2mod.c unload2dep.c
+		   unload2mod.c unload2dep.c ltglobmod1.c ltglobmod2.c
 
 include ../Makeconfig
 
@@ -97,7 +97,7 @@ ifeq (yes,$(build-shared))
 tests = loadtest restest1 preloadtest loadfail multiload origtest resolvfail \
 	constload1 order $(tests-vis-$(have-protected)) noload filter unload \
 	reldep reldep2 reldep3 next $(tests-nodelete-$(have-z-nodelete)) \
-	$(tests-nodlopen-$(have-z-nodlopen)) neededtest unload2
+	$(tests-nodlopen-$(have-z-nodlopen)) neededtest unload2 lateglobal
 tests-vis-yes = vismain
 tests-nodelete-yes = nodelete
 tests-nodlopen-yes = nodlopen
@@ -108,7 +108,8 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
 		$(modules-nodelete-$(have-z-nodelete)) \
 		$(modules-nodlopen-$(have-z-nodlopen)) filtmod1 filtmod2 \
 		reldepmod1 reldepmod2 reldepmod3 reldepmod4 nextmod1 nextmod2 \
-		neededobj1 neededobj2 neededobj3 unload2mod unload2dep
+		neededobj1 neededobj2 neededobj3 unload2mod unload2dep \
+		ltglobmod1 ltglobmod2
 modules-vis-yes = vismod1 vismod2 vismod3
 modules-nodelete-yes = nodelmod1 nodelmod2 nodelmod3 nodelmod4
 modules-nodlopen-yes = nodlopenmod
@@ -255,6 +256,7 @@ $(objpfx)neededobj1.so: $(libdl)
 $(objpfx)neededobj2.so: $(objpfx)neededobj1.so $(libdl)
 $(objpfx)neededobj3.so: $(objpfx)neededobj1.so $(objpfx)neededobj2.so $(libdl)
 $(objpfx)unload2mod.so: $(objpfx)unload2dep.so
+$(objpfx)ltglobmod2.so: $(libdl)
 
 # filtmod1.so has a special rule
 $(filter-out $(objpfx)filtmod1.so, $(test-modules)): $(objpfx)%.so: $(objpfx)%.os
@@ -356,3 +358,6 @@ $(objpfx)next: $(objpfx)nextmod1.so $(objpfx)nextmod2.so $(libdl)
 
 $(objpfx)unload2: $(libdl)
 $(objpfx)unload2.out: $(objpfx)unload2mod.so $(objpfx)unload2dep.so
+
+$(objpfx)lateglobal: $(libdl)
+$(objpfx)lateglobal.out: $(objpfx)ltglobmod1.so $(objpfx)ltglobmod2.so
diff --git a/elf/dl-open.c b/elf/dl-open.c
index a618ca0470..5c078d9be8 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -80,6 +80,87 @@ struct dl_open_args
   struct link_map *map;
 };
 
+
+static int
+add_to_global (struct link_map *new)
+{
+  struct link_map **new_global;
+  unsigned int to_add = 0;
+  unsigned int cnt;
+
+  /* Count the objects we have to put in the global scope.  */
+  for (cnt = 0; cnt < new->l_searchlist.r_nlist; ++cnt)
+    if (new->l_searchlist.r_list[cnt]->l_global == 0)
+      ++to_add;
+
+  /* The symbols of the new objects and its dependencies are to be
+     introduced into the global scope that will be used to resolve
+     references from other dynamically-loaded objects.
+
+     The global scope is the searchlist in the main link map.  We
+     extend this list if necessary.  There is one problem though:
+     since this structure was allocated very early (before the libc
+     is loaded) the memory it uses is allocated by the malloc()-stub
+     in the ld.so.  When we come here these functions are not used
+     anymore.  Instead the malloc() implementation of the libc is
+     used.  But this means the block from the main map cannot be used
+     in an realloc() call.  Therefore we allocate a completely new
+     array the first time we have to add something to the locale scope.  */
+
+  if (_dl_global_scope_alloc == 0)
+    {
+      /* This is the first dynamic object given global scope.  */
+      _dl_global_scope_alloc = _dl_main_searchlist->r_nlist + to_add + 8;
+      new_global = (struct link_map **)
+	malloc (_dl_global_scope_alloc * sizeof (struct link_map *));
+      if (new_global == NULL)
+	{
+	  _dl_global_scope_alloc = 0;
+	nomem:
+	  _dl_signal_error (ENOMEM, new->l_libname->name,
+			    N_("cannot extend global scope"));
+	  return 1;
+	}
+
+      /* Copy over the old entries.  */
+      memcpy (new_global, _dl_main_searchlist->r_list,
+	      (_dl_main_searchlist->r_nlist * sizeof (struct link_map *)));
+
+      _dl_main_searchlist->r_list = new_global;
+    }
+  else if (_dl_main_searchlist->r_nlist + to_add > _dl_global_scope_alloc)
+    {
+      /* We have to extend the existing array of link maps in the
+	 main map.  */
+      new_global = (struct link_map **)
+	realloc (_dl_main_searchlist->r_list,
+		 ((_dl_global_scope_alloc + to_add + 8)
+		  * sizeof (struct link_map *)));
+      if (new_global == NULL)
+	goto nomem;
+
+      _dl_global_scope_alloc += to_add + 8;
+      _dl_main_searchlist->r_list = new_global;
+    }
+
+  /* Now add the new entries.  */
+  for (cnt = 0; cnt < new->l_searchlist.r_nlist; ++cnt)
+    {
+      struct link_map *map = new->l_searchlist.r_list[cnt];
+
+      if (map->l_global == 0)
+	{
+	  map->l_global = 1;
+	  _dl_main_searchlist->r_list[_dl_main_searchlist->r_nlist] = map;
+	  ++_dl_main_searchlist->r_nlist;
+	}
+    }
+
+  /* XXX Do we have to add something to r_dupsearchlist???  --drepper */
+  return 0;
+}
+
+
 static void
 dl_open_worker (void *a)
 {
@@ -172,6 +253,12 @@ dl_open_worker (void *a)
 					 buf + sizeof buf - 1, 10, 0),
 			     "\n\n", NULL);
 	}
+
+      /* If the user requested the object t be in the global namespace
+	 but it is not so far, add it now.  */
+      if ((mode & RTLD_GLOBAL) && new->l_global == 0)
+	(void) add_to_global (new);
+
       /* It was already open.  */
       return;
     }
@@ -232,81 +319,10 @@ dl_open_worker (void *a)
 
   /* Now we can make the new map available in the global scope.  */
   if (mode & RTLD_GLOBAL)
-    {
-      struct link_map **new_global;
-      unsigned int to_add = 0;
-      unsigned int cnt;
-
-      /* Count the objects we have to put in the global scope.  */
-      for (cnt = 0; cnt < new->l_searchlist.r_nlist; ++cnt)
-	if (new->l_searchlist.r_list[cnt]->l_global == 0)
-	  ++to_add;
-
-      /* The symbols of the new objects and its dependencies are to be
-	 introduced into the global scope that will be used to resolve
-	 references from other dynamically-loaded objects.
-
-	 The global scope is the searchlist in the main link map.  We
-	 extend this list if necessary.  There is one problem though:
-	 since this structure was allocated very early (before the libc
-	 is loaded) the memory it uses is allocated by the malloc()-stub
-	 in the ld.so.  When we come here these functions are not used
-	 anymore.  Instead the malloc() implementation of the libc is
-	 used.  But this means the block from the main map cannot be used
-	 in an realloc() call.  Therefore we allocate a completely new
-	 array the first time we have to add something to the locale scope.  */
-
-      if (_dl_global_scope_alloc == 0)
-	{
-	  /* This is the first dynamic object given global scope.  */
-	  _dl_global_scope_alloc = _dl_main_searchlist->r_nlist + to_add + 8;
-	  new_global = (struct link_map **)
-	    malloc (_dl_global_scope_alloc * sizeof (struct link_map *));
-	  if (new_global == NULL)
-	    {
-	      _dl_global_scope_alloc = 0;
-	    nomem:
-	      _dl_signal_error (ENOMEM, new->l_libname->name,
-				N_("cannot extend global scope"));
-	      return;
-	    }
-
-	  /* Copy over the old entries.  */
-	  memcpy (new_global, _dl_main_searchlist->r_list,
-		  (_dl_main_searchlist->r_nlist * sizeof (struct link_map *)));
-
-	  _dl_main_searchlist->r_list = new_global;
-	}
-      else if (_dl_main_searchlist->r_nlist + to_add > _dl_global_scope_alloc)
-	{
-	  /* We have to extend the existing array of link maps in the
-	     main map.  */
-	  new_global = (struct link_map **)
-	    realloc (_dl_main_searchlist->r_list,
-		     ((_dl_global_scope_alloc + to_add + 8)
-		      * sizeof (struct link_map *)));
-	  if (new_global == NULL)
-	    goto nomem;
-
-	  _dl_global_scope_alloc += to_add + 8;
-	  _dl_main_searchlist->r_list = new_global;
-	}
-
-      /* Now add the new entries.  */
-      for (cnt = 0; cnt < new->l_searchlist.r_nlist; ++cnt)
-	{
-	  struct link_map *map = new->l_searchlist.r_list[cnt];
-
-	  if (map->l_global == 0)
-	    {
-	      map->l_global = 1;
-	      _dl_main_searchlist->r_list[_dl_main_searchlist->r_nlist] = map;
-	      ++_dl_main_searchlist->r_nlist;
-	    }
-	}
-
-      /* XXX Do we have to add something to r_dupsearchlist???  --drepper */
-    }
+    /* Move the object in the global namespace.  */
+    if (add_to_global (new) != 0)
+      /* It failed.  */
+      return;
 
   /* Mark the object as not deletable if the RTLD_NODELETE flags was
      passed.  */
diff --git a/elf/lateglobal.c b/elf/lateglobal.c
new file mode 100644
index 0000000000..2f6c2692a6
--- /dev/null
+++ b/elf/lateglobal.c
@@ -0,0 +1,47 @@
+#include <dlfcn.h>
+#include <mcheck.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int
+main (void)
+{
+  void *h[2];
+  int fail;
+  int (*fp) (void);
+
+  mtrace ();
+
+  h[0] = dlopen ("ltglobmod1.so", RTLD_LAZY);
+  if (h == NULL)
+    {
+      printf ("%s: cannot open %s: %s",
+	      __FUNCTION__, "ltglobmod1.so", dlerror ());
+      exit (EXIT_FAILURE);
+    }
+  h[1] = dlopen ("ltglobmod2.so", RTLD_LAZY);
+  if (h == NULL)
+    {
+      printf ("%s: cannot open %s: %s",
+	      __FUNCTION__, "ltglobmod2.so", dlerror ());
+      exit (EXIT_FAILURE);
+    }
+
+  puts ("loaded \"ltglobmod1.so\" without RTLD_GLOBAL");
+
+  fp = dlsym (h[1], "foo");
+  if (fp == NULL)
+    {
+      printf ("cannot get address of `foo': %s", dlerror ());
+      exit (EXIT_FAILURE);
+    }
+
+  fail = fp ();
+
+  puts ("back in main");
+
+  dlclose (h[1]);
+  dlclose (h[0]);
+
+  return fail;
+}
diff --git a/elf/ltglobmod1.c b/elf/ltglobmod1.c
new file mode 100644
index 0000000000..46e74ee2fb
--- /dev/null
+++ b/elf/ltglobmod1.c
@@ -0,0 +1,5 @@
+int
+bar (void)
+{
+  return 42;
+}
diff --git a/elf/ltglobmod2.c b/elf/ltglobmod2.c
new file mode 100644
index 0000000000..bc1cd27c40
--- /dev/null
+++ b/elf/ltglobmod2.c
@@ -0,0 +1,32 @@
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+extern int bar (void);
+
+int
+foo (void)
+{
+  void *h;
+  int res;
+
+  /* Load ltglobalmod1 in the global namespace.  */
+  h = dlopen ("ltglobmod1.so", RTLD_GLOBAL | RTLD_LAZY);
+  if (h == NULL)
+    {
+      printf ("%s: cannot open %s: %s",
+	      __FUNCTION__, "ltglobmod1.so", dlerror ());
+      exit (EXIT_FAILURE);
+    }
+
+  /* Call bar.  This is undefined in the DSO.  */
+  puts ("about to call `bar'");
+  fflush (stdout);
+  res = bar ();
+
+  printf ("bar returned %d\n", res);
+
+  dlclose (h);
+
+  return res != 42;
+}