Thu Jun 13 00:02:25 1996 Roland McGrath <roland@delasyd.gnu.ai.mit.edu>

	* elf/dl-lookup.c (_dl_lookup_symbol): If no value and *REF is
	null, consider it a strong reference and give the error.

Wed Jun 12 15:52:46 1996  Roland McGrath  <roland@delasyd.gnu.ai.mit.edu>

	* elf/dl-open.c (_dl_open): Correctly terminate relocating loop
 	after relocating NEW when it's the only new object.

	* elf/dl-init.c (_dl_init_next): When out of initializers, set
 	_r_debug.r_state to RT_CONSISTENT and call _dl_debug_state just
 	before return.

	* elf/rtld.c (dl_main): Move _dl_debug_initialize call after
 	relocation.  Call it unconditionally and only fill in DT_DEBUG
 	if it's present.  Then call _dl_debug_state with r_state RT_ADD
 	before running initializers.

	* elf/dl-open.c (_dl_open): Call _dl_debug_initialize and then call
 	_dl_debug_state with r_state RT_ADD before running initializers
	* elf/dl-close.c (_dl_close): Call _dl_debug_state with r_state
 	RT_DELETE before running finalizers and with RT_CONSISTENT just
 	before return.

	* elf/Makefile (dl-routines): Add dl-debug.
	* elf/dl-debug.c: New file.
	* elf/rtld.c (_dl_r_debug): Rename to _r_debug and move to dl-debug.c.
	(_dl_r_debug_state): Rename to _dl_debug_state and likewise move.
	(dl_main): Use _dl_debug_initialize.
	* elf/link.h: Fix name to _dl_debug_state in decl.
	(_dl_debug_initialize): Declare new function from dl-debug.c.
	(_r_debug): Declare it.

	* Makerules (distinfo-vars): Add install-{lib,data,bin,sbin,others}.
	In distinfo set $(subdir)-VAR and then set VAR to $($(subdir)-VAR).

	* Makeconfig (rpath-link): New variable; add $(elfobjdir).
	(default-rpath): Use it.
	(built-program-cmd): Use it in LD_LIBRARY_PATH.

	* Makeconfig (sysdep-configures): Prepend $(sysdep_dir) to names tried.

	* sysdeps/unix/Dist: Add make-syscalls.sh.

	* misc/Makefile (headers): Add sys/swap.h.
	* posix/unistd.h: Remove decls for swapon, swapoff.
	* sysdeps/generic/sys/swap.h: New file.
	* sysdeps/unix/sysv/linux/sys/swap.h: New file.

	* sysdeps/unix/sysv/linux/gnu/types.h: Remove temporary hack #define
	of __kernel_fsid_t.  It is correctly defines in <linux/types.h> now.

8 files changed, 108 insertions, 25 deletions

diff --git a/elf/Makefile b/elf/Makefile
index 07ffbd8788..be7604de8e 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -26,7 +26,7 @@ routines	= $(dl-routines) dl-open dl-close dl-symbol dl-support
 # The core dynamic linking functions are in libc for the static and
 # profiled libraries.
 dl-routines	= $(addprefix dl-,load lookup object reloc deps \
-			          runtime error init fini)
+			          runtime error init fini debug)
 # But they are absent from the shared libc, because that code is in ld.so.
 elide-routines.so = $(dl-routines) dl-support
 
diff --git a/elf/dl-close.c b/elf/dl-close.c
index 70d7ab4083..184d38298e 100644
--- a/elf/dl-close.c
+++ b/elf/dl-close.c
@@ -41,6 +41,10 @@ _dl_close (struct link_map *map)
     /* There are still references to this object.  Do nothing more.  */
     return;
 
+  /* Notify the debugger we are about to remove some loaded objects.  */
+  _r_debug.r_state = RT_DELETE;
+  _dl_debug_state ();
+
   list = map->l_searchlist;
 
   /* The search list contains a counted reference to each object it
@@ -105,4 +109,8 @@ _dl_close (struct link_map *map)
     }
 
   free (list);
+
+  /* Notify the debugger those objects are finalized and gone.  */
+  _r_debug.r_state = RT_CONSISTENT;
+  _dl_debug_state ();
 }
diff --git a/elf/dl-debug.c b/elf/dl-debug.c
new file mode 100644
index 0000000000..861e0019e8
--- /dev/null
+++ b/elf/dl-debug.c
@@ -0,0 +1,56 @@
+/* Communicate dynamic linker state to the debugger at runtime.
+Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <link.h>
+
+/* This structure communicates dl state to the debugger.  The debugger
+   normally finds it via the DT_DEBUG entry in the dynamic section, but in
+   a statically-linked program there is no dynamic section for the debugger
+   to examine and it looks for this particular symbol name.  */
+struct r_debug _r_debug;
+
+
+/* Initialize _r_debug if it has not already been done.  The argument is
+   the run-time load address of the dynamic linker, to be put in
+   _r_debug.r_ldbase.  Returns the address of _r_debug.  */
+
+struct r_debug *
+_dl_debug_initialize (ElfW(Addr) ldbase)
+{
+  if (_r_debug.r_brk == 0)
+    {
+      /* Tell the debugger where to find the map of loaded objects.  */
+      _r_debug.r_version = 1	/* R_DEBUG_VERSION XXX */;
+      _r_debug.r_ldbase = _dl_rtld_map.l_addr; /* Record our load address.  */
+      _r_debug.r_map = _dl_loaded;
+      _r_debug.r_brk = (ElfW(Addr)) &_dl_debug_state;
+    }
+
+  return &_r_debug;
+}
+
+
+/* This function exists solely to have a breakpoint set on it by the
+   debugger.  The debugger is supposed to find this function's address by
+   examining the r_brk member of struct r_debug, but GDB 4.15 in fact looks
+   for this particular symbol name in the PT_INTERP file.  */
+void
+_dl_debug_state (void)
+{
+}
diff --git a/elf/dl-init.c b/elf/dl-init.c
index 66ef83e28b..6259c35235 100644
--- a/elf/dl-init.c
+++ b/elf/dl-init.c
@@ -65,5 +65,10 @@ _dl_init_next (struct link_map *map)
       l->l_init_called = 1;
     }
 
+
+  /* Notify the debugger all new objects are now ready to go.  */
+  _r_debug.r_state = RT_CONSISTENT;
+  _dl_debug_state ();
+
   return 0;
 }
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index bbccbc01ef..7ceffa23e1 100644
--- a/elf/dl-lookup.c
+++ b/elf/dl-lookup.c
@@ -129,7 +129,8 @@ _dl_lookup_symbol (const char *undef_name, const ElfW(Sym) **ref,
 	  }
       }
 
-  if (weak_value.s == NULL && ELFW(ST_BIND) ((*ref)->st_info) != STB_WEAK)
+  if (weak_value.s == NULL &&
+      !*ref || ELFW(ST_BIND) ((*ref)->st_info) != STB_WEAK)
     {
       /* We could find no value for a strong reference.  */
       const char msg[] = "undefined symbol: ";
diff --git a/elf/dl-open.c b/elf/dl-open.c
index 9389303b90..373d32dd79 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -29,6 +29,7 @@ _dl_open (struct link_map *parent, const char *file, int mode)
 {
   struct link_map *new, *l;
   ElfW(Addr) init;
+  struct r_debug *r;
 
 
   /* Load the named object.  */
@@ -47,7 +48,7 @@ _dl_open (struct link_map *parent, const char *file, int mode)
   l = new;
   while (l->l_next)
     l = l->l_next;
-  do
+  while (1)
     {
       if (! l->l_relocated)
 	{
@@ -56,8 +57,10 @@ _dl_open (struct link_map *parent, const char *file, int mode)
 	  *_dl_global_scope_end = NULL;
 	}
 
+      if (l == new)
+	break;
       l = l->l_prev;
-    } while (l != new);
+    }
 
   new->l_global = (mode & RTLD_GLOBAL);
   if (new->l_global)
@@ -108,6 +111,14 @@ _dl_open (struct link_map *parent, const char *file, int mode)
 	}
     }
 
+
+  /* Notify the debugger we have added some objects.  We need to call
+     _dl_debug_initialize in a static program in case dynamic linking has
+     not been used before.  */
+  r = _dl_debug_initialize (0);
+  r->r_state = RT_ADD;
+  _dl_debug_state ();
+
   /* Run the initializer functions of new objects.  */
   while (init = _dl_init_next (new))
     (*(void (*) (void)) init) ();
diff --git a/elf/link.h b/elf/link.h
index 6910445095..f43ec411f8 100644
--- a/elf/link.h
+++ b/elf/link.h
@@ -62,6 +62,9 @@ struct r_debug
     ElfW(Addr) r_ldbase;	/* Base address the linker is loaded at.  */
   };
 
+/* This is the instance of that structure used by the dynamic linker.  */
+extern struct r_debug _r_debug;
+
 /* This symbol refers to the "dynamic structure" in the `.dynamic' section
    of whatever module refers to `_DYNAMIC'.  So, to find its own
    `struct r_debug', a program could do:
@@ -291,7 +294,12 @@ extern void _dl_fini (void);
    any shared object mappings.  The `r_state' member of `struct r_debug'
    says what change is taking place.  This function's address is
    the value of the `r_brk' member.  */
-extern void _dl_r_debug_state (void);
+extern void _dl_debug_state (void);
+
+/* Initialize `struct r_debug' if it has not already been done.  The
+   argument is the run-time load address of the dynamic linker, to be put
+   in the `r_ldbase' member.  Returns the address of the structure.  */
+extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase);
 
 
 #endif /* link.h */
diff --git a/elf/rtld.c b/elf/rtld.c
index c9ddfb5c63..7befc0a82f 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -46,8 +46,6 @@ int _dl_argc;
 char **_dl_argv;
 const char *_dl_rpath;
 
-struct r_debug _dl_r_debug;
-
 static void dl_main (const ElfW(Phdr) *phdr,
 		     ElfW(Half) phent,
 		     ElfW(Addr) *user_entry);
@@ -229,12 +227,6 @@ of this helper program; chances are you did not intend to run this program.\n",
     /* Set up our cache of pointers into the hash table.  */
     _dl_setup_hash (l);
 
-  if (l->l_info[DT_DEBUG])
-    /* There is a DT_DEBUG entry in the dynamic section.  Fill it in
-       with the run-time address of the r_debug structure, which we
-       will set up later to communicate with the debugger.  */
-    l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) &_dl_r_debug;
-
   /* Put the link_map for ourselves on the chain so it can be found by
      name.  */
   _dl_rtld_map.l_name = (char *) _dl_rtld_map.l_libname = interpreter_name;
@@ -343,11 +335,20 @@ of this helper program; chances are you did not intend to run this program.\n",
       _dl_relocate_object (&_dl_rtld_map, &_dl_default_scope[2], 0);
   }
 
-  /* Tell the debugger where to find the map of loaded objects.  */
-  _dl_r_debug.r_version = 1	/* R_DEBUG_VERSION XXX */;
-  _dl_r_debug.r_ldbase = _dl_rtld_map.l_addr; /* Record our load address.  */
-  _dl_r_debug.r_map = _dl_loaded;
-  _dl_r_debug.r_brk = (ElfW(Addr)) &_dl_r_debug_state;
+  {
+    /* Initialize _r_debug.  */
+    struct r_debug *r = _dl_debug_initialize (_dl_rtld_map.l_addr);
+
+    l = _dl_loaded;
+    if (l->l_info[DT_DEBUG])
+      /* There is a DT_DEBUG entry in the dynamic section.  Fill it in
+	 with the run-time address of the r_debug structure  */
+      l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r;
+
+    /* Notify the debugger that all objects are now mapped in.  */
+    r->r_state = RT_ADD;
+    _dl_debug_state ();
+  }
 
   if (_dl_rtld_map.l_info[DT_INIT])
     {
@@ -365,10 +366,3 @@ of this helper program; chances are you did not intend to run this program.\n",
   /* Once we return, _dl_sysdep_start will invoke
      the DT_INIT functions and then *USER_ENTRY.  */
 }
-
-/* This function exists solely to have a breakpoint set on it by the
-   debugger.  */
-void
-_dl_r_debug_state (void)
-{
-}