Merge branch 'elf-move'

Conflicts:
	debug/backtracesymsfd.c
	sysdeps/generic/elf/backtracesymsfd.c
	sysdeps/i386/configure.in

1 files changed, 73 insertions, 8 deletions

diff --git a/debug/backtracesyms.c b/debug/backtracesyms.c
index a010664..3fabf26 100644
--- a/debug/backtracesyms.c
+++ b/debug/backtracesyms.c
@@ -1,5 +1,5 @@
 /* Return list with names for address in backtrace.
-   Copyright (C) 1998, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1998-2012 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
 
@@ -17,13 +17,20 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#include <assert.h>
 #include <execinfo.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
+#include <ldsodefs.h>
 
-/* Assume the worst for the width of an address.  */
-#define WORD_WIDTH 16
+#if __ELF_NATIVE_CLASS == 32
+# define WORD_WIDTH 8
+#else
+/* We assyme 64bits.  */
+# define WORD_WIDTH 16
+#endif
 
 
 char **
@@ -31,16 +38,37 @@ __backtrace_symbols (array, size)
      void *const *array;
      int size;
 {
+  Dl_info info[size];
+  int status[size];
   int cnt;
   size_t total = 0;
   char **result;
 
-  /* We can compute the text size needed for the symbols since we print
-     them all as "[+0x<addr>]".  */
-  total = size * (WORD_WIDTH + 6);
+  /* Fill in the information we can get from `dladdr'.  */
+  for (cnt = 0; cnt < size; ++cnt)
+    {
+      struct link_map *map;
+      status[cnt] = _dl_addr (array[cnt], &info[cnt], &map, NULL);
+      if (status[cnt] && info[cnt].dli_fname && info[cnt].dli_fname[0] != '\0')
+	{
+	  /* We have some info, compute the length of the string which will be
+	     "<file-name>(<sym-name>+offset) [address].  */
+	  total += (strlen (info[cnt].dli_fname ?: "")
+		    + strlen (info[cnt].dli_sname ?: "")
+		    + 3 + WORD_WIDTH + 3 + WORD_WIDTH + 5);
+
+	  /* The load bias is more useful to the user than the load
+	     address.  The use of these addresses is to calculate an
+	     address in the ELF file, so its prelinked bias is not
+	     something we want to subtract out.  */
+	  info[cnt].dli_fbase = (void *) map->l_addr;
+	}
+      else
+	total += 5 + WORD_WIDTH;
+    }
 
   /* Allocate memory for the result.  */
-  result = malloc (size * sizeof (char *) + total);
+  result = (char **) malloc (size * sizeof (char *) + total);
   if (result != NULL)
     {
       char *last = (char *) (result + size);
@@ -48,8 +76,45 @@ __backtrace_symbols (array, size)
       for (cnt = 0; cnt < size; ++cnt)
 	{
 	  result[cnt] = last;
-	  last += 1 + sprintf (last, "[+%p]", array[cnt]);
+
+	  if (status[cnt]
+	      && info[cnt].dli_fname != NULL && info[cnt].dli_fname[0] != '\0')
+	    {
+	      if (info[cnt].dli_sname == NULL)
+		/* We found no symbol name to use, so describe it as
+		   relative to the file.  */
+		info[cnt].dli_saddr = info[cnt].dli_fbase;
+
+	      if (info[cnt].dli_sname == NULL && info[cnt].dli_saddr == 0)
+		last += 1 + sprintf (last, "%s(%s) [%p]",
+				     info[cnt].dli_fname ?: "",
+				     info[cnt].dli_sname ?: "",
+				     array[cnt]);
+	      else
+		{
+		  char sign;
+		  ptrdiff_t offset;
+		  if (array[cnt] >= (void *) info[cnt].dli_saddr)
+		    {
+		      sign = '+';
+		      offset = array[cnt] - info[cnt].dli_saddr;
+		    }
+		  else
+		    {
+		      sign = '-';
+		      offset = info[cnt].dli_saddr - array[cnt];
+		    }
+
+		  last += 1 + sprintf (last, "%s(%s%c%#tx) [%p]",
+				       info[cnt].dli_fname ?: "",
+				       info[cnt].dli_sname ?: "",
+				       sign, offset, array[cnt]);
+		}
+	    }
+	  else
+	    last += 1 + sprintf (last, "[%p]", array[cnt]);
 	}
+      assert (last <= (char *) result + size * sizeof (char *) + total);
     }
 
   return result;