* dlfcn/tst-dlinfo.c: New file.

	* dlfcn/Makefile (tests): Add tst-dlinfo.
	($(objpfx)tst-dlinfo): New target.

	* dlfcn/dlinfo.c: New file.
	* dlfcn/Makefile (libdl-routines): Add it.
	* dlfcn/Versions (libdl: GLIBC_2.3.3): Add dlinfo.
	* dlfcn/dlfcn.h [__USE_GNU]: Declare dlinfo.
	[__USE_GNU] (RTLD_DI_*): New enum constants.
	[__USE_GNU] (Dl_serpath, Dl_serinfo): New types.
	* elf/dl-load.c (cache_rpath): New inline function.
	(_dl_map_object): Use it.
	(_dl_rtld_di_serinfo): New function.
	* sysdeps/generic/ldsodefs.h: Declare it.
	* elf/Versions (ld: GLIBC_PRIVATE): Add it.

5 files changed, 243 insertions, 4 deletions

diff --git a/dlfcn/Makefile b/dlfcn/Makefile
index d11336140e..9115d30c2a 100644
--- a/dlfcn/Makefile
+++ b/dlfcn/Makefile
@@ -19,7 +19,8 @@
 subdir		:= dlfcn
 headers		:= bits/dlfcn.h dlfcn.h
 extra-libs	:= libdl
-libdl-routines	:= dlopen dlclose dlsym dlvsym dlerror dladdr dladdr1 eval
+libdl-routines	:= dlopen dlclose dlsym dlvsym dlerror dladdr dladdr1 dlinfo \
+		   eval
 distribute	:= dlopenold.c glreflib1.c glreflib2.c failtestmod.c eval.c \
 		   defaultmod1.c defaultmod2.c errmsg1mod.c modatexit.c \
 		   modcxaatexit.c modstatic.c \
@@ -37,7 +38,7 @@ libdl-shared-only-routines += eval
 
 ifeq (yes,$(build-shared))
 tests = glrefmain failtest tst-dladdr default errmsg1 tstcxaatexit \
-	bug-dlopen1 bug-dlsym1
+	bug-dlopen1 bug-dlsym1 tst-dlinfo
 ifeq (yes,$(have-protected))
 tests += tstatexit
 endif
@@ -74,6 +75,9 @@ $(objpfx)failtest.out: $(objpfx)failtestmod.so
 $(objpfx)tst-dladdr: $(libdl)
 $(objpfx)tst-dladdr.out: $(objpfx)glreflib1.so
 
+$(objpfx)tst-dlinfo: $(libdl)
+$(objpfx)tst-dlinfo.out: $(objpfx)glreflib1.so
+
 LDFLAGS-default = $(LDFLAGS-rdynamic)
 $(objpfx)default: $(libdl) $(objpfx)defaultmod1.so $(objpfx)defaultmod2.so
 $(objpfx)defaultmod1.so: $(libdl) $(common-objpfx)libc_nonshared.a
diff --git a/dlfcn/Versions b/dlfcn/Versions
index ca44a4678f..95ede25e47 100644
--- a/dlfcn/Versions
+++ b/dlfcn/Versions
@@ -6,6 +6,6 @@ libdl {
     dlopen; dlvsym;
   }
   GLIBC_2.3.3 {
-    dladdr1;
+    dladdr1; dlinfo;
   }
 }
diff --git a/dlfcn/dlfcn.h b/dlfcn/dlfcn.h
index 6c8e4abcc4..9d8ee0d6d1 100644
--- a/dlfcn/dlfcn.h
+++ b/dlfcn/dlfcn.h
@@ -21,6 +21,8 @@
 #define	_DLFCN_H 1
 
 #include <features.h>
+#define __need_size_t
+#include <stddef.h>
 
 /* Collect various system dependent definitions and declarations.  */
 #include <bits/dlfcn.h>
@@ -100,7 +102,57 @@ enum
     RTLD_DL_LINKMAP = 2
   };
 
-#endif
+
+/* Get information about the shared object HANDLE refers to.
+   REQUEST is from among the values below, and determines the use of ARG.
+
+   On success, returns zero.  On failure, returns -1 and records an error
+   message to be fetched with `dlerror'.  */
+extern int dlinfo (void *__restrict __handle,
+		   int __request, void *__restrict __arg);
+
+/* These are the possible values for the REQUEST argument to `dlinfo'.  */
+enum
+  {
+    /* Treat ARG as `struct link_map **';
+       store the `struct link_map *' for HANDLE there.  */
+    RTLD_DI_LINKMAP = 2,
+
+    /* Treat ARG as `Dl_serinfo *' (see below), and fill in to describe the
+       directories that will be searched for dependencies of this object.
+       RTLD_DI_SERINFOSIZE fills in just the `dls_cnt' and `dls_size'
+       entries to indicate the size of the buffer that must be passed to
+       RTLD_DI_SERINFO to fill in the full information.  */
+    RTLD_DI_SERINFO = 4,
+    RTLD_DI_SERINFOSIZE = 5,
+
+    /* Treat ARG as `char *', and store there the directory name used to
+       expand $ORIGIN in this shared object's dependency file names.  */
+    RTLD_DI_ORIGIN = 6,
+
+    RTLD_DI_LMID = 1,		/* Unsupported, defined by Solaris.  */
+    RTLD_DI_CONFIGADDR = 3	/* Unsupported, defined by Solaris.  */
+  };
+
+
+/* This is the type of elements in `Dl_serinfo', below.
+   The `dls_name' member points to space in the buffer passed to `dlinfo'.  */
+typedef struct
+{
+  char *dls_name;		/* Name of library search path directory.  */
+  unsigned int dls_flags;	/* Indicates where this directory came from. */
+} Dl_serpath;
+
+/* This is the structure that must be passed (by reference) to `dlinfo' for
+   the RTLD_DI_SERINFO and RTLD_DI_SERINFOSIZE requests.  */
+typedef struct
+{
+  size_t dls_size;		/* Size in bytes of the whole buffer.  */
+  unsigned int dls_cnt;		/* Number of elements in `dls_serpath'.  */
+  Dl_serpath dls_serpath[1];	/* Actually longer, dls_cnt elements.  */
+} Dl_serinfo;
+#endif /* __USE_GNU */
+
 
 __END_DECLS
 
diff --git a/dlfcn/dlinfo.c b/dlfcn/dlinfo.c
new file mode 100644
index 0000000000..37177f1f1b
--- /dev/null
+++ b/dlfcn/dlinfo.c
@@ -0,0 +1,87 @@
+/* dlinfo -- Get information from the dynamic linker.
+   Copyright (C) 2003 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <dlfcn.h>
+#include <link.h>
+#include <ldsodefs.h>
+#include <libintl.h>
+
+struct dlinfo_args
+{
+  ElfW(Addr) caller;
+  void *handle;
+  int request;
+  void *arg;
+};
+
+static void
+dlinfo_doit (void *argsblock)
+{
+  struct dlinfo_args *const args = argsblock;
+  struct link_map *l = args->handle;
+
+#if 0
+  if (args->handle == RTLD_SELF)
+    {
+
+      /* Find the highest-addressed object that CALLER is not below.  */
+      for (l = GL(dl_loaded); l != NULL; l = l->l_next)
+	if (caller >= l->l_map_start && caller < l->l_map_end)
+	  /* There must be exactly one DSO for the range of the virtual
+	     memory.  Otherwise something is really broken.  */
+	  break;
+
+      if (l == NULL)
+	_dl_signal_error (0, NULL, NULL, N_("\
+RTLD_SELF used in code not dynamically loaded"));
+    }
+#endif
+
+  switch (args->request)
+    {
+    case RTLD_DI_LMID:
+    case RTLD_DI_CONFIGADDR:
+    default:
+      _dl_signal_error (0, NULL, NULL, N_("unsupported dlinfo request"));
+      break;
+
+    case RTLD_DI_LINKMAP:
+      *(struct link_map **) args->arg = l;
+      break;
+
+    case RTLD_DI_SERINFO:
+      _dl_rtld_di_serinfo (l, args->arg, false);
+      break;
+    case RTLD_DI_SERINFOSIZE:
+      _dl_rtld_di_serinfo (l, args->arg, true);
+      break;
+
+    case RTLD_DI_ORIGIN:
+      strcpy (args->arg, l->l_origin);
+      break;
+    }
+}
+
+int
+dlinfo (void *handle, int request, void *arg)
+{
+  struct dlinfo_args args = { (ElfW(Addr)) RETURN_ADDRESS (0),
+			      handle, request, arg };
+  return _dlerror_run (&dlinfo_doit, &args) ? -1 : 0;
+}
diff --git a/dlfcn/tst-dlinfo.c b/dlfcn/tst-dlinfo.c
new file mode 100644
index 0000000000..70906ebdf1
--- /dev/null
+++ b/dlfcn/tst-dlinfo.c
@@ -0,0 +1,96 @@
+/* Test for dlinfo.
+   Copyright (C) 2003 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <error.h>
+
+#define TEST_FUNCTION do_test ()
+
+static int
+do_test (void)
+{
+  int status = 0;
+
+  void *handle = dlopen ("glreflib1.so", RTLD_NOW);
+  if (handle == NULL)
+    error (EXIT_FAILURE, 0, "cannot load: glreflib1.so: %s", dlerror ());
+
+#define TRY(req, arg)							      \
+  if (dlinfo (handle, req, arg) != 0)					      \
+    {									      \
+      printf ("dlinfo failed for %s: %s\n", #req, dlerror ());		      \
+      status = 1;							      \
+    }									      \
+  else
+
+  struct link_map *l;
+  TRY (RTLD_DI_LINKMAP, &l)
+    {
+      if (l != handle)
+	{
+	  printf ("bogus link_map? %p != %p\n", l, handle);
+	  status = 1;
+	}
+    }
+
+  char origin[8192];		/* >= PATH_MAX, in theory */
+  TRY (RTLD_DI_ORIGIN, origin)
+    {
+      printf ("origin: %s\n", origin);
+    }
+
+  Dl_serinfo counts;
+  TRY (RTLD_DI_SERINFOSIZE, &counts)
+    {
+      Dl_serinfo *buf = alloca (counts.dls_size);
+      buf->dls_cnt = counts.dls_cnt;
+      buf->dls_size = counts.dls_size;
+      printf ("%u library directories\n", buf->dls_cnt);
+      TRY (RTLD_DI_SERINFO, buf)
+	{
+	  if (counts.dls_cnt != buf->dls_cnt)
+	    {
+	      printf ("??? became %u library directories\n", buf->dls_cnt);
+	      status = 1;
+	    }
+	  for (unsigned int i = 0; i < buf->dls_cnt; ++i)
+	    printf ("\t%#02x\t%s\n",
+		    buf->dls_serpath[i].dls_flags,
+		    buf->dls_serpath[i].dls_name);
+	}
+    }
+
+  unsigned long int lmid = 0xdeadbeefUL;
+  if (dlinfo (handle, RTLD_DI_LMID, &lmid) != 0)
+    printf ("dlinfo refuses RTLD_DI_LMID: %s\n", dlerror ());
+  else
+    {
+      printf ("dlinfo RTLD_DI_LMID worked? %#lx\n", lmid);
+      status = lmid == 0xdeadbeefUL;
+    }
+
+#undef TRY
+  dlclose (handle);
+
+  return status;
+}
+
+#include "../test-skeleton.c"