Prepare for radical source tree reorganization.zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 230 insertions, 0 deletions

diff --git a/REORG.TODO/elf/dl-error-skeleton.c b/REORG.TODO/elf/dl-error-skeleton.c
new file mode 100644
index 0000000000..8e5888d4bd
--- /dev/null
+++ b/REORG.TODO/elf/dl-error-skeleton.c
@@ -0,0 +1,230 @@
+/* Template for error handling for runtime dynamic linker.
+   Copyright (C) 1995-2017 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* The following macro needs to be defined before including this
+   skeleton file:
+
+   DL_ERROR_BOOTSTRAP
+
+     If 1, do not use TLS and implement _dl_signal_cerror and
+     _dl_receive_error.  If 0, TLS is used, and the variants with
+     error callbacks are not provided.  */
+
+
+#include <libintl.h>
+#include <setjmp.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+#include <stdio.h>
+
+/* This structure communicates state between _dl_catch_error and
+   _dl_signal_error.  */
+struct catch
+  {
+    const char **objname;	/* Object/File name.  */
+    const char **errstring;	/* Error detail filled in here.  */
+    bool *malloced;		/* Nonzero if the string is malloced
+				   by the libc malloc.  */
+    volatile int *errcode;	/* Return value of _dl_signal_error.  */
+    jmp_buf env;		/* longjmp here on error.  */
+  };
+
+/* Multiple threads at once can use the `_dl_catch_error' function.  The
+   calls can come from `_dl_map_object_deps', `_dlerror_run', or from
+   any of the libc functionality which loads dynamic objects (NSS, iconv).
+   Therefore we have to be prepared to save the state in thread-local
+   memory.  */
+#if !DL_ERROR_BOOTSTRAP
+static __thread struct catch *catch_hook attribute_tls_model_ie;
+#else
+/* The version of this code in ld.so cannot use thread-local variables
+   and is used during bootstrap only.  */
+static struct catch *catch_hook;
+#endif
+
+/* This message we return as a last resort.  We define the string in a
+   variable since we have to avoid freeing it and so have to enable
+   a pointer comparison.  See below and in dlfcn/dlerror.c.  */
+static const char _dl_out_of_memory[] = "out of memory";
+
+#if DL_ERROR_BOOTSTRAP
+/* This points to a function which is called when an continuable error is
+   received.  Unlike the handling of `catch' this function may return.
+   The arguments will be the `errstring' and `objname'.
+
+   Since this functionality is not used in normal programs (only in ld.so)
+   we do not care about multi-threaded programs here.  We keep this as a
+   global variable.  */
+static receiver_fct receiver;
+#endif /* DL_ERROR_BOOTSTRAP */
+
+void
+internal_function
+_dl_signal_error (int errcode, const char *objname, const char *occation,
+		  const char *errstring)
+{
+  struct catch *lcatch = catch_hook;
+
+  if (! errstring)
+    errstring = N_("DYNAMIC LINKER BUG!!!");
+
+  if (objname == NULL)
+    objname = "";
+  if (lcatch != NULL)
+    {
+      /* We are inside _dl_catch_error.  Return to it.  We have to
+	 duplicate the error string since it might be allocated on the
+	 stack.  The object name is always a string constant.  */
+      size_t len_objname = strlen (objname) + 1;
+      size_t len_errstring = strlen (errstring) + 1;
+
+      char *errstring_copy = malloc (len_objname + len_errstring);
+      if (errstring_copy != NULL)
+	{
+	  /* Make a copy of the object file name and the error string.  */
+	  *lcatch->objname = memcpy (__mempcpy (errstring_copy,
+						errstring, len_errstring),
+				     objname, len_objname);
+	  *lcatch->errstring = errstring_copy;
+
+	  /* If the main executable is relocated it means the libc's malloc
+	     is used.  */
+          bool malloced = true;
+#ifdef SHARED
+	  malloced = (GL(dl_ns)[LM_ID_BASE]._ns_loaded != NULL
+                      && (GL(dl_ns)[LM_ID_BASE]._ns_loaded->l_relocated != 0));
+#endif
+	  *lcatch->malloced = malloced;
+	}
+      else
+	{
+	  /* This is better than nothing.  */
+	  *lcatch->objname = "";
+	  *lcatch->errstring = _dl_out_of_memory;
+	  *lcatch->malloced = false;
+	}
+
+      *lcatch->errcode = errcode;
+
+      /* We do not restore the signal mask because none was saved.  */
+      __longjmp (lcatch->env[0].__jmpbuf, 1);
+    }
+  else
+    {
+      /* Lossage while resolving the program's own symbols is always fatal.  */
+      char buffer[1024];
+      _dl_fatal_printf ("%s: %s: %s%s%s%s%s\n",
+			RTLD_PROGNAME,
+			occation ?: N_("error while loading shared libraries"),
+			objname, *objname ? ": " : "",
+			errstring, errcode ? ": " : "",
+			(errcode
+			 ? __strerror_r (errcode, buffer, sizeof buffer)
+			 : ""));
+    }
+}
+libc_hidden_def (_dl_signal_error)
+
+
+#if DL_ERROR_BOOTSTRAP
+void
+internal_function
+_dl_signal_cerror (int errcode, const char *objname, const char *occation,
+		   const char *errstring)
+{
+  if (__builtin_expect (GLRO(dl_debug_mask)
+			& ~(DL_DEBUG_STATISTICS|DL_DEBUG_PRELINK), 0))
+    _dl_debug_printf ("%s: error: %s: %s (%s)\n", objname, occation,
+		      errstring, receiver ? "continued" : "fatal");
+
+  if (receiver)
+    {
+      /* We are inside _dl_receive_error.  Call the user supplied
+	 handler and resume the work.  The receiver will still be
+	 installed.  */
+      (*receiver) (errcode, objname, errstring);
+    }
+  else
+    _dl_signal_error (errcode, objname, occation, errstring);
+}
+#endif /* DL_ERROR_BOOTSTRAP */
+
+
+int
+internal_function
+_dl_catch_error (const char **objname, const char **errstring,
+		 bool *mallocedp, void (*operate) (void *), void *args)
+{
+  /* We need not handle `receiver' since setting a `catch' is handled
+     before it.  */
+
+  /* Only this needs to be marked volatile, because it is the only local
+     variable that gets changed between the setjmp invocation and the
+     longjmp call.  All others are just set here (before setjmp) and read
+     in _dl_signal_error (before longjmp).  */
+  volatile int errcode;
+
+  struct catch c;
+  /* Don't use an initializer since we don't need to clear C.env.  */
+  c.objname = objname;
+  c.errstring = errstring;
+  c.malloced = mallocedp;
+  c.errcode = &errcode;
+
+  struct catch *const old = catch_hook;
+  catch_hook = &c;
+
+  /* Do not save the signal mask.  */
+  if (__builtin_expect (__sigsetjmp (c.env, 0), 0) == 0)
+    {
+      (*operate) (args);
+      catch_hook = old;
+      *objname = NULL;
+      *errstring = NULL;
+      *mallocedp = false;
+      return 0;
+    }
+
+  /* We get here only if we longjmp'd out of OPERATE.  _dl_signal_error has
+     already stored values into *OBJNAME, *ERRSTRING, and *MALLOCEDP.  */
+  catch_hook = old;
+  return errcode;
+}
+libc_hidden_def (_dl_catch_error)
+
+#if DL_ERROR_BOOTSTRAP
+void
+internal_function
+_dl_receive_error (receiver_fct fct, void (*operate) (void *), void *args)
+{
+  struct catch *old_catch = catch_hook;
+  receiver_fct old_receiver = receiver;
+
+  /* Set the new values.  */
+  catch_hook = NULL;
+  receiver = fct;
+
+  (*operate) (args);
+
+  catch_hook = old_catch;
+  receiver = old_receiver;
+}
+#endif /* DL_ERROR_BOOTSTRAP */