Squashed 'third_party/elfutils/' content from commit 555e15e

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/tests/dwflsyms.c b/tests/dwflsyms.c
new file mode 100644
index 0000000..49ac334
--- /dev/null
+++ b/tests/dwflsyms.c
@@ -0,0 +1,226 @@
+/* Test program for libdwfl symbol resolving
+   Copyright (C) 2013 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   elfutils 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+#include <assert.h>
+#include <inttypes.h>
+#include ELFUTILS_HEADER(dwfl)
+#include <elf.h>
+#include <dwarf.h>
+#include <argp.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include <stdlib.h>
+#include <error.h>
+#include <string.h>
+
+static const char *
+gelf_type (GElf_Sym *sym)
+{
+  switch (GELF_ST_TYPE (sym->st_info))
+    {
+    case STT_NOTYPE:
+      return "NOTYPE";
+    case STT_OBJECT:
+      return "OBJECT";
+    case STT_FUNC:
+      return "FUNC";
+    case STT_SECTION:
+      return "SECTION";
+    case STT_FILE:
+      return "FILE";
+    case STT_COMMON:
+      return "COMMON";
+    case STT_TLS:
+      return "TLS";
+    default:
+      return "UNKNOWN";
+    }
+}
+
+static const char *
+gelf_bind (GElf_Sym *sym)
+{
+  switch (GELF_ST_BIND (sym->st_info))
+    {
+    case STB_LOCAL:
+      return "LOCAL";
+    case STB_GLOBAL:
+      return "GLOBAL";
+    case STB_WEAK:
+      return "WEAK";
+    default:
+      return "UNKNOWN";
+    }
+}
+
+static int
+gelf_bind_order (GElf_Sym *sym)
+{
+  switch (GELF_ST_BIND (sym->st_info))
+    {
+    case STB_LOCAL:
+      return 1;
+    case STB_WEAK:
+      return 2;
+    case STB_GLOBAL:
+      return 3;
+    default:
+      return 0;
+    }
+}
+
+static const char *
+elf_section_name (Elf *elf, GElf_Word shndx)
+{
+  GElf_Ehdr ehdr;
+  GElf_Shdr shdr;
+  Elf_Scn *scn = elf_getscn (elf, shndx);
+  gelf_getshdr (scn, &shdr);
+  gelf_getehdr (elf, &ehdr);
+  return elf_strptr (elf, ehdr.e_shstrndx, shdr.sh_name);
+}
+
+bool
+addr_in_section (Elf *elf, GElf_Word shndx, GElf_Addr addr)
+{
+  GElf_Shdr shdr;
+  Elf_Scn *scn = elf_getscn (elf, shndx);
+  gelf_getshdr (scn, &shdr);
+  return addr >= shdr.sh_addr && addr < shdr.sh_addr + shdr.sh_size;
+}
+
+static int
+list_syms (struct Dwfl_Module *mod,
+	   void **user __attribute__ ((unused)), const char *mod_name,
+	   Dwarf_Addr low_addr __attribute__ ((unused)),
+	   void *arg __attribute__ ((unused)))
+{
+  int syms = dwfl_module_getsymtab (mod);
+  if (syms < 0)
+    {
+      printf ("%s: %s\n", mod_name, dwfl_errmsg (-1));
+      return DWARF_CB_OK;
+    }
+
+  for (int ndx = 0; ndx < syms; ndx++)
+    {
+      GElf_Sym sym;
+      GElf_Word shndxp;
+      Elf *elf;
+      Dwarf_Addr bias;
+      const char *name = dwfl_module_getsym (mod, ndx, &sym, &shndxp);
+
+      printf("%4d: %s\t%s\t%s (%" PRIu64 ") %#" PRIx64,
+	     ndx, gelf_type (&sym), gelf_bind (&sym), name,
+	     sym.st_size, sym.st_value);
+
+      /* The info variant doesn't adjust st_value but returns the (possible)
+	 adjusted value separately. */
+      GElf_Addr value;
+      GElf_Sym isym;
+      name = dwfl_module_getsym_info (mod, ndx, &isym, &value, &shndxp,
+				      &elf, &bias);
+
+      GElf_Ehdr ehdr;
+      gelf_getehdr (elf, &ehdr);
+
+      // getsym st_values might or might not be adjusted depending on section.
+      // For ET_REL the adjustment is section relative.
+      assert (sym.st_value == isym.st_value
+	      || sym.st_value == isym.st_value + bias
+	      || ehdr.e_type == ET_REL);
+
+      /* And the reverse, which works for function symbols at least.
+	 Note this only works because the st.value is adjusted by
+	 dwfl_module_getsym ().  */
+      if (GELF_ST_TYPE (sym.st_info) == STT_FUNC && shndxp != SHN_UNDEF)
+	{
+	  /* Make sure the adjusted value really falls in the elf section. */
+          assert (addr_in_section (elf, shndxp, sym.st_value - bias));
+
+	  GElf_Addr addr = value;
+	  GElf_Sym asym;
+	  GElf_Word ashndxp;
+	  Elf *aelf;
+	  Dwarf_Addr abias;
+	  GElf_Off off;
+	  const char *aname = dwfl_module_addrinfo (mod, addr, &off, &asym,
+						    &ashndxp, &aelf, &abias);
+
+	  /* Make sure the adjusted value really falls in the elf section. */
+          assert (addr_in_section (aelf, ashndxp, asym.st_value)
+		  || ehdr.e_type == ET_REL);
+
+	  /* Either they are the same symbol (name), the binding of
+	     asym is "stronger" (or equal) to sym or asym is more specific
+	     (has a lower address) than sym.  */
+	  assert ((strcmp (name, aname) == 0
+		   || gelf_bind_order (&asym) >= gelf_bind_order (&sym))
+		  && value <= sym.st_value);
+
+	  addr = sym.st_value;
+	  int res = dwfl_module_relocate_address (mod, &addr);
+	  assert (res != -1);
+	  if (shndxp < SHN_LORESERVE)
+	    printf(", rel: %#" PRIx64 " (%s)", addr,
+		   elf_section_name (elf, shndxp));
+	  else
+	    printf(", rel: %#" PRIx64 "", addr);
+
+	  /* Print the section of the actual value if different from sym.  */
+	  if (value != isym.st_value + bias && ehdr.e_type != ET_REL)
+	    {
+	      GElf_Addr ebias;
+	      addr = value;
+	      Elf_Scn *scn = dwfl_module_address_section (mod, &addr, &ebias);
+	      GElf_Shdr shdr_mem;
+	      GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
+	      Elf *melf = dwfl_module_getelf (mod, &ebias);
+	      gelf_getehdr (melf, &ehdr);
+	      const char *sname = elf_strptr (melf, ehdr.e_shstrndx,
+					      shdr->sh_name);
+	      printf (" [%#" PRIx64 ", rel: %#" PRIx64 " (%s)]",
+		      value, addr, sname);
+	    }
+
+	}
+      printf ("\n");
+    }
+
+  return DWARF_CB_OK;
+}
+
+int
+main (int argc, char *argv[])
+{
+  int remaining;
+  Dwfl *dwfl;
+  error_t res;
+
+  res = argp_parse (dwfl_standard_argp (), argc, argv, 0, &remaining, &dwfl);
+  assert (res == 0 && dwfl != NULL);
+
+  ptrdiff_t off = 0;
+  do
+    off = dwfl_getmodules (dwfl, list_syms, NULL, off);
+  while (off > 0);
+
+  dwfl_end (dwfl);
+
+  return off;
+}