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, 217 insertions, 0 deletions

diff --git a/REORG.TODO/csu/libc-tls.c b/REORG.TODO/csu/libc-tls.c
new file mode 100644
index 0000000000..3c897bf28b
--- /dev/null
+++ b/REORG.TODO/csu/libc-tls.c
@@ -0,0 +1,217 @@
+/* Initialization code for TLS in statically linked application.
+   Copyright (C) 2002-2017 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/>.  */
+
+#include <errno.h>
+#include <ldsodefs.h>
+#include <tls.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/param.h>
+
+
+#ifdef SHARED
+ #error makefile bug, this file is for static only
+#endif
+
+dtv_t _dl_static_dtv[2 + TLS_SLOTINFO_SURPLUS];
+
+
+static struct
+{
+  struct dtv_slotinfo_list si;
+  /* The dtv_slotinfo_list data structure does not include the actual
+     information since it is defined as an array of size zero.  We define
+     here the necessary entries.  Note that it is not important whether
+     there is padding or not since we will always access the information
+     through the 'si' element.  */
+  struct dtv_slotinfo info[2 + TLS_SLOTINFO_SURPLUS];
+} static_slotinfo;
+
+
+/* Highest dtv index currently needed.  */
+size_t _dl_tls_max_dtv_idx;
+/* Flag signalling whether there are gaps in the module ID allocation.  */
+bool _dl_tls_dtv_gaps;
+/* Information about the dtv slots.  */
+struct dtv_slotinfo_list *_dl_tls_dtv_slotinfo_list;
+/* Number of modules in the static TLS block.  */
+size_t _dl_tls_static_nelem;
+/* Size of the static TLS block.  Giving this initialized value
+   preallocates some surplus bytes in the static TLS area.  */
+size_t _dl_tls_static_size = 2048;
+/* Size actually allocated in the static TLS block.  */
+size_t _dl_tls_static_used;
+/* Alignment requirement of the static TLS block.  */
+size_t _dl_tls_static_align;
+
+/* Generation counter for the dtv.  */
+size_t _dl_tls_generation;
+
+
+/* Additional definitions needed by TLS initialization.  */
+#ifdef TLS_INIT_HELPER
+TLS_INIT_HELPER
+#endif
+
+static void
+init_slotinfo (void)
+{
+  /* Create the slotinfo list.  */
+  static_slotinfo.si.len = (((char *) (&static_slotinfo + 1)
+			     - (char *) &static_slotinfo.si.slotinfo[0])
+			    / sizeof static_slotinfo.si.slotinfo[0]);
+  // static_slotinfo.si.next = NULL;	already zero
+
+  /* The slotinfo list.  Will be extended by the code doing dynamic
+     linking.  */
+  GL(dl_tls_max_dtv_idx) = 1;
+  GL(dl_tls_dtv_slotinfo_list) = &static_slotinfo.si;
+}
+
+static void
+init_static_tls (size_t memsz, size_t align)
+{
+  /* That is the size of the TLS memory for this object.  The initialized
+     value of _dl_tls_static_size is provided by dl-open.c to request some
+     surplus that permits dynamic loading of modules with IE-model TLS.  */
+  GL(dl_tls_static_size) = roundup (memsz + GL(dl_tls_static_size),
+				    TLS_TCB_ALIGN);
+#if TLS_TCB_AT_TP
+  GL(dl_tls_static_size) += TLS_TCB_SIZE;
+#endif
+  GL(dl_tls_static_used) = memsz;
+  /* The alignment requirement for the static TLS block.  */
+  GL(dl_tls_static_align) = align;
+  /* Number of elements in the static TLS block.  */
+  GL(dl_tls_static_nelem) = GL(dl_tls_max_dtv_idx);
+}
+
+void
+__libc_setup_tls (void)
+{
+  void *tlsblock;
+  size_t memsz = 0;
+  size_t filesz = 0;
+  void *initimage = NULL;
+  size_t align = 0;
+  size_t max_align = TCB_ALIGNMENT;
+  size_t tcb_offset;
+  const ElfW(Phdr) *phdr;
+
+  /* Look through the TLS segment if there is any.  */
+  if (_dl_phdr != NULL)
+    for (phdr = _dl_phdr; phdr < &_dl_phdr[_dl_phnum]; ++phdr)
+      if (phdr->p_type == PT_TLS)
+	{
+	  /* Remember the values we need.  */
+	  memsz = phdr->p_memsz;
+	  filesz = phdr->p_filesz;
+	  initimage = (void *) phdr->p_vaddr;
+	  align = phdr->p_align;
+	  if (phdr->p_align > max_align)
+	    max_align = phdr->p_align;
+	  break;
+	}
+
+  /* We have to set up the TCB block which also (possibly) contains
+     'errno'.  Therefore we avoid 'malloc' which might touch 'errno'.
+     Instead we use 'sbrk' which would only uses 'errno' if it fails.
+     In this case we are right away out of memory and the user gets
+     what she/he deserves.
+
+     The initialized value of _dl_tls_static_size is provided by dl-open.c
+     to request some surplus that permits dynamic loading of modules with
+     IE-model TLS.  */
+#if TLS_TCB_AT_TP
+  /* Align the TCB offset to the maximum alignment, as
+     _dl_allocate_tls_storage (in elf/dl-tls.c) does using __libc_memalign
+     and dl_tls_static_align.  */
+  tcb_offset = roundup (memsz + GL(dl_tls_static_size), max_align);
+  tlsblock = __sbrk (tcb_offset + TLS_INIT_TCB_SIZE + max_align);
+#elif TLS_DTV_AT_TP
+  tcb_offset = roundup (TLS_INIT_TCB_SIZE, align ?: 1);
+  tlsblock = __sbrk (tcb_offset + memsz + max_align
+		     + TLS_PRE_TCB_SIZE + GL(dl_tls_static_size));
+  tlsblock += TLS_PRE_TCB_SIZE;
+#else
+  /* In case a model with a different layout for the TCB and DTV
+     is defined add another #elif here and in the following #ifs.  */
+# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+#endif
+
+  /* Align the TLS block.  */
+  tlsblock = (void *) (((uintptr_t) tlsblock + max_align - 1)
+		       & ~(max_align - 1));
+
+  /* Initialize the dtv.  [0] is the length, [1] the generation counter.  */
+  _dl_static_dtv[0].counter = (sizeof (_dl_static_dtv) / sizeof (_dl_static_dtv[0])) - 2;
+  // _dl_static_dtv[1].counter = 0;		would be needed if not already done
+
+  struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
+
+  /* Initialize the TLS block.  */
+#if TLS_TCB_AT_TP
+  _dl_static_dtv[2].pointer.val = ((char *) tlsblock + tcb_offset
+			       - roundup (memsz, align ?: 1));
+  main_map->l_tls_offset = roundup (memsz, align ?: 1);
+#elif TLS_DTV_AT_TP
+  _dl_static_dtv[2].pointer.val = (char *) tlsblock + tcb_offset;
+  main_map->l_tls_offset = tcb_offset;
+#else
+# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+#endif
+  _dl_static_dtv[2].pointer.to_free = NULL;
+  /* sbrk gives us zero'd memory, so we don't need to clear the remainder.  */
+  memcpy (_dl_static_dtv[2].pointer.val, initimage, filesz);
+
+  /* Install the pointer to the dtv.  */
+
+  /* Initialize the thread pointer.  */
+#if TLS_TCB_AT_TP
+  INSTALL_DTV ((char *) tlsblock + tcb_offset, _dl_static_dtv);
+
+  const char *lossage = TLS_INIT_TP ((char *) tlsblock + tcb_offset);
+#elif TLS_DTV_AT_TP
+  INSTALL_DTV (tlsblock, _dl_static_dtv);
+  const char *lossage = TLS_INIT_TP (tlsblock);
+#else
+# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+#endif
+  if (__builtin_expect (lossage != NULL, 0))
+    __libc_fatal (lossage);
+
+  /* Update the executable's link map with enough information to make
+     the TLS routines happy.  */
+  main_map->l_tls_align = align;
+  main_map->l_tls_blocksize = memsz;
+  main_map->l_tls_initimage = initimage;
+  main_map->l_tls_initimage_size = filesz;
+  main_map->l_tls_modid = 1;
+
+  init_slotinfo ();
+  // static_slotinfo.si.slotinfo[1].gen = 0; already zero
+  static_slotinfo.si.slotinfo[1].map = main_map;
+
+  memsz = roundup (memsz, align ?: 1);
+
+#if TLS_DTV_AT_TP
+  memsz += tcb_offset;
+#endif
+
+  init_static_tls (memsz, MAX (TLS_TCB_ALIGN, max_align));
+}