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-rw-r--r--elf/dl-close.c23
-rw-r--r--elf/dl-deps.c11
-rw-r--r--elf/dl-open.c25
-rw-r--r--elf/dl-version.c9
-rw-r--r--elf/dlclose.c4
5 files changed, 53 insertions, 19 deletions
diff --git a/elf/dl-close.c b/elf/dl-close.c
index 7e851cd0af..fa9e92cb9f 100644
--- a/elf/dl-close.c
+++ b/elf/dl-close.c
@@ -1,5 +1,5 @@
-/* _dl_close -- Close a shared object opened by `_dl_open'.
-   Copyright (C) 1996 Free Software Foundation, Inc.
+/* Close a shared object opened by `_dl_open'.
+   Copyright (C) 1996, 1997 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
@@ -23,8 +23,14 @@
 #include <string.h>
 #include <sys/types.h>
 #include <sys/mman.h>
+#include <libc-lock.h>
 
 
+/* During the program run we must not modify the global data of
+   loaded shared object simultanously in two threads.  Therefore we
+   protect `dlopen' and `dlclose' in dlclose.c.  */
+__libc_lock_define (extern, _dl_load_lock)
+
 #define LOSE(s) _dl_signal_error (0, map->l_name, s)
 
 void
@@ -36,10 +42,16 @@ _dl_close (struct link_map *map)
   if (map->l_opencount == 0)
     LOSE ("shared object not open");
 
+  /* Acquire the lock.  */
+  __libc_lock_lock (_dl_load_lock);
+
   /* Decrement the reference count.  */
   if (--map->l_opencount > 0 || map->l_type != lt_loaded)
-    /* There are still references to this object.  Do nothing more.  */
-    return;
+    {
+      /* There are still references to this object.  Do nothing more.  */
+      __libc_lock_unlock (_dl_load_lock);
+      return;
+    }
 
   /* Notify the debugger we are about to remove some loaded objects.  */
   _r_debug.r_state = RT_DELETE;
@@ -114,4 +126,7 @@ _dl_close (struct link_map *map)
   /* Notify the debugger those objects are finalized and gone.  */
   _r_debug.r_state = RT_CONSISTENT;
   _dl_debug_state ();
+
+  /* Release the lock.  */
+  __libc_lock_unlock (_dl_load_lock);
 }
diff --git a/elf/dl-deps.c b/elf/dl-deps.c
index 38db7677b0..27de231dff 100644
--- a/elf/dl-deps.c
+++ b/elf/dl-deps.c
@@ -84,7 +84,7 @@ _dl_map_object_deps (struct link_map *map,
 		     int trace_mode)
 {
   struct list known[1 + npreloads + 1];
-  struct list *runp, *head, *utail, *dtail;
+  struct list *runp, *utail, *dtail;
   unsigned int nlist, nduplist, i;
 
   inline void preload (struct link_map *map)
@@ -116,9 +116,6 @@ _dl_map_object_deps (struct link_map *map,
   known[nlist - 1].unique = NULL;
   known[nlist - 1].dup = NULL;
 
-  /* Pointer to the first member of the unique and duplicate list.  */
-  head = known;
-
   /* Pointer to last unique object.  */
   utail = &known[nlist - 1];
   /* Pointer to last loaded object.  */
@@ -300,7 +297,7 @@ _dl_map_object_deps (struct link_map *map,
 			   situation is really not that frequent.  So
 			   we don't use a double-linked list but
 			   instead search for the preceding element.  */
-			late = head;
+			late = known;
 			while (late->unique != orig)
 			  late = late->unique;
 			late->unique = newp;
@@ -361,7 +358,7 @@ _dl_map_object_deps (struct link_map *map,
 		      "cannot allocate symbol search list");
   map->l_nsearchlist = nlist;
 
-  for (nlist = 0, runp = head; runp; runp = runp->unique)
+  for (nlist = 0, runp = known; runp; runp = runp->unique)
     {
       map->l_searchlist[nlist++] = runp->map;
 
@@ -380,7 +377,7 @@ _dl_map_object_deps (struct link_map *map,
 	_dl_signal_error (ENOMEM, map->l_name,
 			  "cannot allocate symbol search list");
 
-      for (nlist = 0, runp = head; runp; runp = runp->dup)
+      for (nlist = 0, runp = known; runp; runp = runp->dup)
 	map->l_dupsearchlist[nlist++] = runp->map;
     }
 }
diff --git a/elf/dl-open.c b/elf/dl-open.c
index 529806cc36..113e472165 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -21,6 +21,7 @@
 #include <dlfcn.h>
 #include <stdlib.h>
 #include <errno.h>
+#include <libc-lock.h>
 
 
 extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
@@ -38,6 +39,17 @@ extern char **__environ;
 
 size_t _dl_global_scope_alloc;
 
+
+/* During the program run we must not modify the global data of
+   loaded shared object simultanously in two threads.  Therefore we
+   protect `_dl_open' and `_dl_close' in dl-close.c.
+
+   This must be a recursive lock since the initializer function of
+   the loaded object might as well require a call to this function.
+   At this time it is not anymore a problem to modify the tables.  */
+__libc_lock_define_initialized_recursive (, _dl_load_lock)
+
+
 struct link_map *
 _dl_open (const char *file, int mode)
 {
@@ -45,11 +57,17 @@ _dl_open (const char *file, int mode)
   ElfW(Addr) init;
   struct r_debug *r;
 
+  /* Make sure we are alone.  */
+  __libc_lock_lock (_dl_load_lock);
+
   /* Load the named object.  */
   new = _dl_map_object (NULL, file, lt_loaded, 0);
   if (new->l_searchlist)
-    /* It was already open.  */
-    return new;
+    {
+      /* It was already open.  */
+      __libc_lock_unlock (_dl_load_lock);
+      return new;
+    }
 
   /* Load that object's dependencies.  */
   _dl_map_object_deps (new, NULL, 0, 0);
@@ -152,5 +170,8 @@ _dl_open (const char *file, int mode)
        has loaded a dynamic object now has competition.  */
     __libc_multiple_libcs = 1;
 
+  /* Release the lock.  */
+  __libc_lock_unlock (_dl_load_lock);
+
   return new;
 }
diff --git a/elf/dl-version.c b/elf/dl-version.c
index b5515c86e0..0f98dd057c 100644
--- a/elf/dl-version.c
+++ b/elf/dl-version.c
@@ -46,7 +46,7 @@ extern char **_dl_argv;
 									      \
     cp = result = alloca (len);						      \
     for (cnt = 0; cnt < sizeof (all) / sizeof (all[0]); ++cnt)		      \
-      cp = stpcpy (cp, all[cnt]);					      \
+      cp = __stpcpy (cp, all[cnt]);					      \
 									      \
     result;								      \
   })
@@ -55,11 +55,12 @@ extern char **_dl_argv;
 static inline struct link_map *
 find_needed (const char *name, struct link_map *map)
 {
+  struct link_map *tmap;
   unsigned int n;
 
-  for (n = 0; n < _dl_loaded->l_nsearchlist; ++n)
-    if (_dl_name_match_p (name, _dl_loaded->l_searchlist[n]))
-      return _dl_loaded->l_searchlist[n];
+  for (tmap = _dl_loaded; tmap != NULL; tmap = tmap->l_next)
+    if (_dl_name_match_p (name, tmap))
+      return tmap;
 
   /* The required object is not in the global scope, look to see if it is
      a dependency of the current object.  */
diff --git a/elf/dlclose.c b/elf/dlclose.c
index d96ffc9cc1..a2ec750baf 100644
--- a/elf/dlclose.c
+++ b/elf/dlclose.c
@@ -1,5 +1,5 @@
-/* dlclose -- Close a handle opened by `dlopen'.
-   Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+/* Close a handle opened by `dlopen'.
+   Copyright (C) 1995, 1996, 1997 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
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-10-24 03:51:00 +0000