1 files changed, 123 insertions, 0 deletions
diff --git a/libdwarf/dwarf_offdie.c b/libdwarf/dwarf_offdie.c
new file mode 100644
index 00000000..2e94d2ea
--- /dev/null
+++ b/libdwarf/dwarf_offdie.c
@@ -0,0 +1,123 @@
+/* Return die at given offset.
+   Copyright (C) 2000, 2002 Red Hat, Inc.
+   Written by Ulrich Drepper <[email protected]>, 2000.
+
+   This program is Open Source software; you can redistribute it and/or
+   modify it under the terms of the Open Software License version 1.0 as
+   published by the Open Source Initiative.
+
+   You should have received a copy of the Open Software License along
+   with this program; if not, you may obtain a copy of the Open Software
+   License version 1.0 from http://www.opensource.org/licenses/osl.php or
+   by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
+   3001 King Ranch Road, Ukiah, CA 95482.   */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <dwarf.h>
+#include <stdlib.h>
+
+#include <libdwarfP.h>
+
+
+/* XXX This function will have to be optimized.  The search is too linear
+   to be performed too often -> O(n�).  */
+static Dwarf_CU_Info
+find_cu (Dwarf_Debug dbg, Dwarf_Off offset, Dwarf_Error *error)
+{
+  Dwarf_CU_Info cu;
+  Dwarf_Word cu_offset;
+
+  /* Search in the CUs already known.  */
+  for (cu = dbg->cu_list; cu != NULL; cu = cu->next)
+    if (cu->offset <= offset
+	&& cu->offset + 2 * cu->offset_size - 4 + cu->length > offset)
+      return cu;
+
+  /* The CU is not yet loaded.  Do this now.  */
+  if (dbg->cu_list_tail == NULL)
+    cu_offset = 0;
+  else
+    cu_offset = (dbg->cu_list_tail->offset
+		 + 2 * dbg->cu_list_tail->offset_size - 4
+		 + dbg->cu_list_tail->length);
+
+  while (1)
+    {
+      /* Get next CU and add it to the end of the list.  */
+      if (__libdwarf_get_cu_at_offset (dbg, cu_offset, &cu, error)
+	  != DW_DLV_OK)
+	return NULL;
+
+      /* Offset of next CU.  */
+      cu_offset += 2 * cu->offset_size - 4 + cu->length;
+
+      /* If this the CU we are looking for?  */
+      if (offset < cu_offset)
+	return cu;
+    }
+}
+
+
+int
+dwarf_offdie (dbg, offset, return_die, error)
+     Dwarf_Debug dbg;
+     Dwarf_Off offset;
+     Dwarf_Die *return_die;
+     Dwarf_Error *error;
+{
+  Dwarf_CU_Info cu;
+  Dwarf_Die new_die;
+  Dwarf_Small *die_addr;
+  Dwarf_Word u128;
+
+  if (offset >= dbg->sections[IDX_debug_info].size)
+    {
+      /* Completely out of bounds.  */
+      __libdwarf_error (dbg, error, DW_E_INVALID_OFFSET);
+      return DW_DLV_ERROR;
+    }
+
+  /* Find the compile unit this address belongs to.  */
+  cu = find_cu (dbg, offset, error);
+  if (cu == NULL)
+    return DW_DLV_ERROR;
+
+  /* Creata a new die.  */
+  new_die = (Dwarf_Die) malloc (sizeof (struct Dwarf_Die_s));
+  if (new_die == NULL)
+    {
+      __libdwarf_error (dbg, error, DW_E_NOMEM);
+      return DW_DLV_ERROR;
+    }
+
+#ifdef DWARF_DEBUG
+  new_die->memtag = DW_DLA_DIE;
+#endif
+
+  /* Remember the address.  */
+  die_addr = (Dwarf_Small *) dbg->sections[IDX_debug_info].addr + offset;
+  new_die->addr = die_addr;
+
+  /* And the compile unit.  */
+  new_die->cu = cu;
+
+  /* 7.5.2  Debugging Information Entry
+
+     Each debugging information entry begins with an unsigned LEB128
+     number containing the abbreviation code for the entry.  */
+  get_uleb128 (u128, die_addr);
+
+  /* Find the abbreviation.  */
+  new_die->abbrev = __libdwarf_get_abbrev (dbg, cu, u128, error);
+  if (new_die->abbrev == NULL)
+    {
+      free (new_die);
+      return DW_DLV_ERROR;
+    }
+
+  *return_die = new_die;
+  return DW_DLV_OK;
+}