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-rw-r--r--libdw/dwarf_getaranges.c265
1 files changed, 265 insertions, 0 deletions
diff --git a/libdw/dwarf_getaranges.c b/libdw/dwarf_getaranges.c
new file mode 100644
index 00000000..4953af53
--- /dev/null
+++ b/libdw/dwarf_getaranges.c
@@ -0,0 +1,265 @@
+/* Return list address ranges.
+ Copyright (C) 2000-2010 Red Hat, Inc.
+ This file is part of elfutils.
+ Written by Ulrich Drepper <drepper@redhat.com>, 2000.
+
+ 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 <stdlib.h>
+#include <assert.h>
+#include "libdwP.h"
+#include <dwarf.h>
+
+struct arangelist
+{
+ Dwarf_Arange arange;
+ struct arangelist *next;
+};
+
+/* Compare by Dwarf_Arange.addr, given pointers into an array of pointeers. */
+static int
+compare_aranges (const void *a, const void *b)
+{
+ struct arangelist *const *p1 = a, *const *p2 = b;
+ struct arangelist *l1 = *p1, *l2 = *p2;
+ if (l1->arange.addr != l2->arange.addr)
+ return (l1->arange.addr < l2->arange.addr) ? -1 : 1;
+ return 0;
+}
+
+int
+dwarf_getaranges (dbg, aranges, naranges)
+ Dwarf *dbg;
+ Dwarf_Aranges **aranges;
+ size_t *naranges;
+{
+ if (dbg == NULL)
+ return -1;
+
+ if (dbg->aranges != NULL)
+ {
+ *aranges = dbg->aranges;
+ if (naranges != NULL)
+ *naranges = dbg->aranges->naranges;
+ return 0;
+ }
+
+ if (dbg->sectiondata[IDX_debug_aranges] == NULL)
+ {
+ /* No such section. */
+ *aranges = NULL;
+ if (naranges != NULL)
+ *naranges = 0;
+ return 0;
+ }
+
+ if (dbg->sectiondata[IDX_debug_aranges]->d_buf == NULL)
+ return -1;
+
+ struct arangelist *arangelist = NULL;
+ unsigned int narangelist = 0;
+
+ const unsigned char *readp = dbg->sectiondata[IDX_debug_aranges]->d_buf;
+ const unsigned char *readendp
+ = readp + dbg->sectiondata[IDX_debug_aranges]->d_size;
+
+ while (readp < readendp)
+ {
+ const unsigned char *hdrstart = readp;
+
+ /* Each entry starts with a header:
+
+ 1. A 4-byte or 12-byte length containing the length of the
+ set of entries for this compilation unit, not including the
+ length field itself. [...]
+
+ 2. A 2-byte version identifier containing the value 2 for
+ DWARF Version 2.1.
+
+ 3. A 4-byte or 8-byte offset into the .debug_info section. [...]
+
+ 4. A 1-byte unsigned integer containing the size in bytes of
+ an address (or the offset portion of an address for segmented
+ addressing) on the target system.
+
+ 5. A 1-byte unsigned integer containing the size in bytes of
+ a segment descriptor on the target system. */
+ Dwarf_Word length = read_4ubyte_unaligned_inc (dbg, readp);
+ unsigned int length_bytes = 4;
+ if (length == DWARF3_LENGTH_64_BIT)
+ {
+ length = read_8ubyte_unaligned_inc (dbg, readp);
+ length_bytes = 8;
+ }
+ else if (unlikely (length >= DWARF3_LENGTH_MIN_ESCAPE_CODE
+ && length <= DWARF3_LENGTH_MAX_ESCAPE_CODE))
+ goto invalid;
+
+ unsigned int version = read_2ubyte_unaligned_inc (dbg, readp);
+ if (version != 2)
+ {
+ invalid:
+ __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ fail:
+ while (arangelist != NULL)
+ {
+ struct arangelist *next = arangelist->next;
+ free (arangelist);
+ arangelist = next;
+ }
+ return -1;
+ }
+
+ Dwarf_Word offset;
+ if (__libdw_read_offset_inc (dbg,
+ IDX_debug_aranges, &readp,
+ length_bytes, &offset, IDX_debug_info, 4))
+ goto fail;
+
+ unsigned int address_size = *readp++;
+ if (address_size != 4 && address_size != 8)
+ goto invalid;
+
+ /* We don't actually support segment selectors. */
+ unsigned int segment_size = *readp++;
+ if (segment_size != 0)
+ goto invalid;
+
+ /* Round the address to the next multiple of 2*address_size. */
+ readp += ((2 * address_size - ((readp - hdrstart) % (2 * address_size)))
+ % (2 * address_size));
+
+ while (1)
+ {
+ Dwarf_Word range_address;
+ Dwarf_Word range_length;
+
+ if (__libdw_read_address_inc (dbg, IDX_debug_aranges, &readp,
+ address_size, &range_address))
+ goto fail;
+
+ if (address_size == 4)
+ range_length = read_4ubyte_unaligned_inc (dbg, readp);
+ else
+ range_length = read_8ubyte_unaligned_inc (dbg, readp);
+
+ /* Two zero values mark the end. */
+ if (range_address == 0 && range_length == 0)
+ break;
+
+ /* We don't use alloca for these temporary structures because
+ the total number of them can be quite large. */
+ struct arangelist *new_arange = malloc (sizeof *new_arange);
+ if (unlikely (new_arange == NULL))
+ {
+ __libdw_seterrno (DWARF_E_NOMEM);
+ goto fail;
+ }
+
+ new_arange->arange.addr = range_address;
+ new_arange->arange.length = range_length;
+
+ /* We store the actual CU DIE offset, not the CU header offset. */
+ const char *cu_header = (dbg->sectiondata[IDX_debug_info]->d_buf
+ + offset);
+ unsigned int offset_size;
+ if (read_4ubyte_unaligned_noncvt (cu_header) == DWARF3_LENGTH_64_BIT)
+ offset_size = 8;
+ else
+ offset_size = 4;
+ new_arange->arange.offset = DIE_OFFSET_FROM_CU_OFFSET (offset,
+ offset_size,
+ false);
+
+ new_arange->next = arangelist;
+ arangelist = new_arange;
+ ++narangelist;
+
+ /* Sanity-check the data. */
+ if (unlikely (new_arange->arange.offset
+ >= dbg->sectiondata[IDX_debug_info]->d_size))
+ goto invalid;
+ }
+ }
+
+ if (narangelist == 0)
+ {
+ assert (arangelist == NULL);
+ if (naranges != NULL)
+ *naranges = 0;
+ *aranges = NULL;
+ return 0;
+ }
+
+ /* Allocate the array for the result. */
+ void *buf = libdw_alloc (dbg, Dwarf_Aranges,
+ sizeof (Dwarf_Aranges)
+ + narangelist * sizeof (Dwarf_Arange), 1);
+
+ /* First use the buffer for the pointers, and sort the entries.
+ We'll write the pointers in the end of the buffer, and then
+ copy into the buffer from the beginning so the overlap works. */
+ assert (sizeof (Dwarf_Arange) >= sizeof (Dwarf_Arange *));
+ struct arangelist **sortaranges
+ = (buf + sizeof (Dwarf_Aranges)
+ + ((sizeof (Dwarf_Arange) - sizeof sortaranges[0]) * narangelist));
+
+ /* The list is in LIFO order and usually they come in clumps with
+ ascending addresses. So fill from the back to probably start with
+ runs already in order before we sort. */
+ unsigned int i = narangelist;
+ while (i-- > 0)
+ {
+ sortaranges[i] = arangelist;
+ arangelist = arangelist->next;
+ }
+ assert (arangelist == NULL);
+
+ /* Sort by ascending address. */
+ qsort (sortaranges, narangelist, sizeof sortaranges[0], &compare_aranges);
+
+ /* Now that they are sorted, put them in the final array.
+ The buffers overlap, so we've clobbered the early elements
+ of SORTARANGES by the time we're reading the later ones. */
+ *aranges = buf;
+ (*aranges)->dbg = dbg;
+ (*aranges)->naranges = narangelist;
+ dbg->aranges = *aranges;
+ if (naranges != NULL)
+ *naranges = narangelist;
+ for (i = 0; i < narangelist; ++i)
+ {
+ struct arangelist *elt = sortaranges[i];
+ (*aranges)->info[i] = elt->arange;
+ free (elt);
+ }
+
+ return 0;
+}
+INTDEF(dwarf_getaranges)