Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libdw/libdw_findcu.c b/libdw/libdw_findcu.c
new file mode 100644
index 0000000..4e025e2
--- /dev/null
+++ b/libdw/libdw_findcu.c
@@ -0,0 +1,169 @@
+/* Find CU for given offset.
+ Copyright (C) 2003-2010, 2014 Red Hat, Inc.
+ This file is part of elfutils.
+ Written by Ulrich Drepper <drepper@redhat.com>, 2003.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * the GNU General Public License as published by the Free
+ Software Foundation; either version 2 of the License, or (at
+ your option) any later version
+
+ or both in parallel, as here.
+
+ 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <search.h>
+#include "libdwP.h"
+
+static int
+findcu_cb (const void *arg1, const void *arg2)
+{
+ struct Dwarf_CU *cu1 = (struct Dwarf_CU *) arg1;
+ struct Dwarf_CU *cu2 = (struct Dwarf_CU *) arg2;
+
+ /* Find out which of the two arguments is the search value. It has
+ end offset 0. */
+ if (cu1->end == 0)
+ {
+ if (cu1->start < cu2->start)
+ return -1;
+ if (cu1->start >= cu2->end)
+ return 1;
+ }
+ else
+ {
+ if (cu2->start < cu1->start)
+ return 1;
+ if (cu2->start >= cu1->end)
+ return -1;
+ }
+
+ return 0;
+}
+
+struct Dwarf_CU *
+internal_function
+__libdw_intern_next_unit (Dwarf *dbg, bool debug_types)
+{
+ Dwarf_Off *const offsetp
+ = debug_types ? &dbg->next_tu_offset : &dbg->next_cu_offset;
+ void **tree = debug_types ? &dbg->tu_tree : &dbg->cu_tree;
+
+ Dwarf_Off oldoff = *offsetp;
+ uint16_t version;
+ uint8_t address_size;
+ uint8_t offset_size;
+ Dwarf_Off abbrev_offset;
+ uint64_t type_sig8 = 0;
+ Dwarf_Off type_offset = 0;
+
+ if (INTUSE(dwarf_next_unit) (dbg, oldoff, offsetp, NULL,
+ &version, &abbrev_offset,
+ &address_size, &offset_size,
+ debug_types ? &type_sig8 : NULL,
+ debug_types ? &type_offset : NULL) != 0)
+ /* No more entries. */
+ return NULL;
+
+ /* We only know how to handle the DWARF version 2 through 4 formats. */
+ if (unlikely (version < 2) || unlikely (version > 4))
+ {
+ __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ return NULL;
+ }
+
+ /* Invalid or truncated debug section data? */
+ size_t sec_idx = debug_types ? IDX_debug_types : IDX_debug_info;
+ Elf_Data *data = dbg->sectiondata[sec_idx];
+ if (unlikely (*offsetp > data->d_size))
+ *offsetp = data->d_size;
+
+ /* Create an entry for this CU. */
+ struct Dwarf_CU *newp = libdw_typed_alloc (dbg, struct Dwarf_CU);
+
+ newp->dbg = dbg;
+ newp->sec_idx = sec_idx;
+ newp->start = oldoff;
+ newp->end = *offsetp;
+ newp->address_size = address_size;
+ newp->offset_size = offset_size;
+ newp->version = version;
+ newp->type_sig8 = type_sig8;
+ newp->type_offset = type_offset;
+ Dwarf_Abbrev_Hash_init (&newp->abbrev_hash, 41);
+ newp->orig_abbrev_offset = newp->last_abbrev_offset = abbrev_offset;
+ newp->lines = NULL;
+ newp->locs = NULL;
+
+ if (debug_types)
+ Dwarf_Sig8_Hash_insert (&dbg->sig8_hash, type_sig8, newp);
+
+ newp->startp = data->d_buf + newp->start;
+ newp->endp = data->d_buf + newp->end;
+
+ /* Add the new entry to the search tree. */
+ if (tsearch (newp, tree, findcu_cb) == NULL)
+ {
+ /* Something went wrong. Undo the operation. */
+ *offsetp = oldoff;
+ __libdw_seterrno (DWARF_E_NOMEM);
+ return NULL;
+ }
+
+ return newp;
+}
+
+struct Dwarf_CU *
+internal_function
+__libdw_findcu (Dwarf *dbg, Dwarf_Off start, bool debug_types)
+{
+ void **tree = debug_types ? &dbg->tu_tree : &dbg->cu_tree;
+ Dwarf_Off *next_offset
+ = debug_types ? &dbg->next_tu_offset : &dbg->next_cu_offset;
+
+ /* Maybe we already know that CU. */
+ struct Dwarf_CU fake = { .start = start, .end = 0 };
+ struct Dwarf_CU **found = tfind (&fake, tree, findcu_cb);
+ if (found != NULL)
+ return *found;
+
+ if (start < *next_offset)
+ {
+ __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ return NULL;
+ }
+
+ /* No. Then read more CUs. */
+ while (1)
+ {
+ struct Dwarf_CU *newp = __libdw_intern_next_unit (dbg, debug_types);
+ if (newp == NULL)
+ return NULL;
+
+ /* Is this the one we are looking for? */
+ if (start < *next_offset)
+ // XXX Match exact offset.
+ return newp;
+ }
+ /* NOTREACHED */
+}