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-rw-r--r--REORG.TODO/debug/backtracesyms.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/REORG.TODO/debug/backtracesyms.c b/REORG.TODO/debug/backtracesyms.c
new file mode 100644
index 0000000000..d2d8b26505
--- /dev/null
+++ b/REORG.TODO/debug/backtracesyms.c
@@ -0,0 +1,120 @@
+/* Return list with names for address in backtrace.
+   Copyright (C) 1998-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+   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>
+#include <execinfo.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <ldsodefs.h>
+
+#if __ELF_NATIVE_CLASS == 32
+# define WORD_WIDTH 8
+#else
+/* We assume 64bits.  */
+# define WORD_WIDTH 16
+#endif
+
+
+char **
+__backtrace_symbols (void *const *array, int size)
+{
+  Dl_info info[size];
+  int status[size];
+  int cnt;
+  size_t total = 0;
+  char **result;
+
+  /* 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 = (char **) malloc (size * sizeof (char *) + total);
+  if (result != NULL)
+    {
+      char *last = (char *) (result + size);
+
+      for (cnt = 0; cnt < size; ++cnt)
+	{
+	  result[cnt] = last;
+
+	  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;
+}
+weak_alias (__backtrace_symbols, backtrace_symbols)