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+/* CIE reading.
+ Copyright (C) 2009-2010 Red Hat, Inc.
+ This file is part of Red Hat elfutils.
+
+ Red Hat elfutils 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; version 2 of the License.
+
+ Red Hat 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 Red Hat elfutils; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
+
+ In addition, as a special exception, Red Hat, Inc. gives You the
+ additional right to link the code of Red Hat elfutils with code licensed
+ under any Open Source Initiative certified open source license
+ (http://www.opensource.org/licenses/index.php) which requires the
+ distribution of source code with any binary distribution and to
+ distribute linked combinations of the two. Non-GPL Code permitted under
+ this exception must only link to the code of Red Hat elfutils through
+ those well defined interfaces identified in the file named EXCEPTION
+ found in the source code files (the "Approved Interfaces"). The files
+ of Non-GPL Code may instantiate templates or use macros or inline
+ functions from the Approved Interfaces without causing the resulting
+ work to be covered by the GNU General Public License. Only Red Hat,
+ Inc. may make changes or additions to the list of Approved Interfaces.
+ Red Hat's grant of this exception is conditioned upon your not adding
+ any new exceptions. If you wish to add a new Approved Interface or
+ exception, please contact Red Hat. You must obey the GNU General Public
+ License in all respects for all of the Red Hat elfutils code and other
+ code used in conjunction with Red Hat elfutils except the Non-GPL Code
+ covered by this exception. If you modify this file, you may extend this
+ exception to your version of the file, but you are not obligated to do
+ so. If you do not wish to provide this exception without modification,
+ you must delete this exception statement from your version and license
+ this file solely under the GPL without exception.
+
+ Red Hat elfutils is an included package of the Open Invention Network.
+ An included package of the Open Invention Network is a package for which
+ Open Invention Network licensees cross-license their patents. No patent
+ license is granted, either expressly or impliedly, by designation as an
+ included package. Should you wish to participate in the Open Invention
+ Network licensing program, please visit www.openinventionnetwork.com
+ <http://www.openinventionnetwork.com>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "cfi.h"
+#include "encoded-value.h"
+#include <assert.h>
+#include <search.h>
+#include <stdlib.h>
+
+
+static int
+compare_cie (const void *a, const void *b)
+{
+ const struct dwarf_cie *cie1 = a;
+ const struct dwarf_cie *cie2 = b;
+ if (cie1->offset < cie2->offset)
+ return -1;
+ if (cie1->offset > cie2->offset)
+ return 1;
+ return 0;
+}
+
+/* There is no CIE at OFFSET in the tree. Add it. */
+static struct dwarf_cie *
+intern_new_cie (Dwarf_CFI *cache, Dwarf_Off offset, const Dwarf_CIE *info)
+{
+ struct dwarf_cie *cie = malloc (sizeof (struct dwarf_cie));
+ if (cie == NULL)
+ {
+ __libdw_seterrno (DWARF_E_NOMEM);
+ return NULL;
+ }
+
+ cie->offset = offset;
+ cie->code_alignment_factor = info->code_alignment_factor;
+ cie->data_alignment_factor = info->data_alignment_factor;
+ cie->return_address_register = info->return_address_register;
+
+ cie->fde_augmentation_data_size = 0;
+ cie->sized_augmentation_data = false;
+ cie->signal_frame = false;
+
+ cie->fde_encoding = DW_EH_PE_absptr;
+ cie->lsda_encoding = DW_EH_PE_omit;
+
+ /* Grok the augmentation string and its data. */
+ const uint8_t *data = info->augmentation_data;
+ for (const char *ap = info->augmentation; *ap != '\0'; ++ap)
+ {
+ uint8_t encoding;
+ switch (*ap)
+ {
+ case 'z':
+ cie->sized_augmentation_data = true;
+ continue;
+
+ case 'S':
+ cie->signal_frame = true;
+ continue;
+
+ case 'L': /* LSDA pointer encoding byte. */
+ cie->lsda_encoding = *data++;
+ if (!cie->sized_augmentation_data)
+ cie->fde_augmentation_data_size
+ += encoded_value_size (&cache->data->d, cache->e_ident,
+ cie->lsda_encoding, NULL);
+ continue;
+
+ case 'R': /* FDE address encoding byte. */
+ cie->fde_encoding = *data++;
+ continue;
+
+ case 'P': /* Skip personality routine. */
+ encoding = *data++;
+ data += encoded_value_size (&cache->data->d, cache->e_ident,
+ encoding, data);
+ continue;
+
+ default:
+ /* Unknown augmentation string. If we have 'z' we can ignore it,
+ otherwise we must bail out. */
+ if (cie->sized_augmentation_data)
+ continue;
+ }
+ /* We only get here when we need to bail out. */
+ break;
+ }
+
+ if ((cie->fde_encoding & 0x0f) == DW_EH_PE_absptr)
+ {
+ /* Canonicalize encoding to a specific size. */
+ assert (DW_EH_PE_absptr == 0);
+
+ /* XXX should get from dwarf_next_cfi with v4 header. */
+ uint_fast8_t address_size
+ = cache->e_ident[EI_CLASS] == ELFCLASS32 ? 4 : 8;
+ switch (address_size)
+ {
+ case 8:
+ cie->fde_encoding |= DW_EH_PE_udata8;
+ break;
+ case 4:
+ cie->fde_encoding |= DW_EH_PE_udata4;
+ break;
+ default:
+ free (cie);
+ __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ return NULL;
+ }
+ }
+
+ /* Save the initial instructions to be played out into initial state. */
+ cie->initial_instructions = info->initial_instructions;
+ cie->initial_instructions_end = info->initial_instructions_end;
+ cie->initial_state = NULL;
+
+ /* Add the new entry to the search tree. */
+ if (tsearch (cie, &cache->cie_tree, &compare_cie) == NULL)
+ {
+ free (cie);
+ __libdw_seterrno (DWARF_E_NOMEM);
+ return NULL;
+ }
+
+ return cie;
+}
+
+/* Look up a CIE_pointer for random access. */
+struct dwarf_cie *
+internal_function
+__libdw_find_cie (Dwarf_CFI *cache, Dwarf_Off offset)
+{
+ const struct dwarf_cie cie_key = { .offset = offset };
+ struct dwarf_cie **found = tfind (&cie_key, &cache->cie_tree, &compare_cie);
+ if (found != NULL)
+ return *found;
+
+ /* We have not read this CIE yet. Go find it. */
+ Dwarf_Off next_offset = offset;
+ Dwarf_CFI_Entry entry;
+ int result = INTUSE(dwarf_next_cfi) (cache->e_ident,
+ &cache->data->d, CFI_IS_EH (cache),
+ offset, &next_offset, &entry);
+ if (result != 0 || entry.cie.CIE_id != DW_CIE_ID_64)
+ {
+ __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ return NULL;
+ }
+
+ /* If this happened to be what we would have read next, notice it. */
+ if (cache->next_offset == offset)
+ cache->next_offset = next_offset;
+
+ return intern_new_cie (cache, offset, &entry.cie);
+}
+
+/* Enter a CIE encountered while reading through for FDEs. */
+void
+internal_function
+__libdw_intern_cie (Dwarf_CFI *cache, Dwarf_Off offset, const Dwarf_CIE *info)
+{
+ const struct dwarf_cie cie_key = { .offset = offset };
+ struct dwarf_cie **found = tfind (&cie_key, &cache->cie_tree, &compare_cie);
+ if (found == NULL)
+ /* We have not read this CIE yet. Enter it. */
+ (void) intern_new_cie (cache, offset, info);
+}
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