Set up the data structures for vDSO in libc.a

1 files changed, 161 insertions, 0 deletions

diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h
new file mode 100644
index 0000000..ffac75f
--- /dev/null
+++ b/elf/get-dynamic-info.h
@@ -0,0 +1,161 @@
+/* Read the dynamic section at DYN and fill in INFO with indices DT_*.
+   Copyright (C) 2012 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 <assert.h>
+
+#ifndef RESOLVE_MAP
+static
+#else
+auto
+#endif
+inline void __attribute__ ((unused, always_inline))
+elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
+{
+  ElfW(Dyn) *dyn = l->l_ld;
+  ElfW(Dyn) **info;
+#if __ELF_NATIVE_CLASS == 32
+  typedef Elf32_Word d_tag_utype;
+#elif __ELF_NATIVE_CLASS == 64
+  typedef Elf64_Xword d_tag_utype;
+#endif
+
+#ifndef RTLD_BOOTSTRAP
+  if (dyn == NULL)
+    return;
+#endif
+
+  info = l->l_info;
+
+  while (dyn->d_tag != DT_NULL)
+    {
+      if ((d_tag_utype) dyn->d_tag < DT_NUM)
+	info[dyn->d_tag] = dyn;
+      else if (dyn->d_tag >= DT_LOPROC &&
+	       dyn->d_tag < DT_LOPROC + DT_THISPROCNUM)
+	info[dyn->d_tag - DT_LOPROC + DT_NUM] = dyn;
+      else if ((d_tag_utype) DT_VERSIONTAGIDX (dyn->d_tag) < DT_VERSIONTAGNUM)
+	info[VERSYMIDX (dyn->d_tag)] = dyn;
+      else if ((d_tag_utype) DT_EXTRATAGIDX (dyn->d_tag) < DT_EXTRANUM)
+	info[DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+	     + DT_VERSIONTAGNUM] = dyn;
+      else if ((d_tag_utype) DT_VALTAGIDX (dyn->d_tag) < DT_VALNUM)
+	info[DT_VALTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+	     + DT_VERSIONTAGNUM + DT_EXTRANUM] = dyn;
+      else if ((d_tag_utype) DT_ADDRTAGIDX (dyn->d_tag) < DT_ADDRNUM)
+	info[DT_ADDRTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+	     + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] = dyn;
+      ++dyn;
+    }
+
+#define DL_RO_DYN_TEMP_CNT	8
+
+#ifndef DL_RO_DYN_SECTION
+  /* Don't adjust .dynamic unnecessarily.  */
+  if (l->l_addr != 0)
+    {
+      ElfW(Addr) l_addr = l->l_addr;
+      int cnt = 0;
+
+# define ADJUST_DYN_INFO(tag) \
+      do								      \
+	if (info[tag] != NULL)						      \
+	  {								      \
+	    if (temp)							      \
+	      {								      \
+		temp[cnt].d_tag = info[tag]->d_tag;			      \
+		temp[cnt].d_un.d_ptr = info[tag]->d_un.d_ptr + l_addr;	      \
+		info[tag] = temp + cnt++;				      \
+	      }								      \
+	    else							      \
+	      info[tag]->d_un.d_ptr += l_addr;				      \
+	  }								      \
+      while (0)
+
+      ADJUST_DYN_INFO (DT_HASH);
+      ADJUST_DYN_INFO (DT_PLTGOT);
+      ADJUST_DYN_INFO (DT_STRTAB);
+      ADJUST_DYN_INFO (DT_SYMTAB);
+# if ! ELF_MACHINE_NO_RELA
+      ADJUST_DYN_INFO (DT_RELA);
+# endif
+# if ! ELF_MACHINE_NO_REL
+      ADJUST_DYN_INFO (DT_REL);
+# endif
+      ADJUST_DYN_INFO (DT_JMPREL);
+      ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM));
+      ADJUST_DYN_INFO (DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM
+		       + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM);
+# undef ADJUST_DYN_INFO
+      assert (cnt <= DL_RO_DYN_TEMP_CNT);
+    }
+#endif
+  if (info[DT_PLTREL] != NULL)
+    {
+#if ELF_MACHINE_NO_RELA
+      assert (info[DT_PLTREL]->d_un.d_val == DT_REL);
+#elif ELF_MACHINE_NO_REL
+      assert (info[DT_PLTREL]->d_un.d_val == DT_RELA);
+#else
+      assert (info[DT_PLTREL]->d_un.d_val == DT_REL
+	      || info[DT_PLTREL]->d_un.d_val == DT_RELA);
+#endif
+    }
+#if ! ELF_MACHINE_NO_RELA
+  if (info[DT_RELA] != NULL)
+    assert (info[DT_RELAENT]->d_un.d_val == sizeof (ElfW(Rela)));
+# endif
+# if ! ELF_MACHINE_NO_REL
+  if (info[DT_REL] != NULL)
+    assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel)));
+#endif
+#ifdef RTLD_BOOTSTRAP
+  /* Only the bind now flags are allowed.  */
+  assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL
+	  || (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0);
+  assert (info[DT_FLAGS] == NULL
+	  || (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0);
+  /* Flags must not be set for ld.so.  */
+  assert (info[DT_RUNPATH] == NULL);
+  assert (info[DT_RPATH] == NULL);
+#else
+  if (info[DT_FLAGS] != NULL)
+    {
+      /* Flags are used.  Translate to the old form where available.
+	 Since these l_info entries are only tested for NULL pointers it
+	 is ok if they point to the DT_FLAGS entry.  */
+      l->l_flags = info[DT_FLAGS]->d_un.d_val;
+
+      if (l->l_flags & DF_SYMBOLIC)
+	info[DT_SYMBOLIC] = info[DT_FLAGS];
+      if (l->l_flags & DF_TEXTREL)
+	info[DT_TEXTREL] = info[DT_FLAGS];
+      if (l->l_flags & DF_BIND_NOW)
+	info[DT_BIND_NOW] = info[DT_FLAGS];
+    }
+  if (info[VERSYMIDX (DT_FLAGS_1)] != NULL)
+    {
+      l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val;
+
+      if (l->l_flags_1 & DF_1_NOW)
+	info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)];
+    }
+  if (info[DT_RUNPATH] != NULL)
+    /* If both RUNPATH and RPATH are given, the latter is ignored.  */
+    info[DT_RPATH] = NULL;
+#endif
+}