/* Return list address ranges. Copyright (C) 2000-2010 Red Hat, Inc. This file is part of elfutils. Written by Ulrich Drepper , 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 . */ #ifdef HAVE_CONFIG_H # include #endif #include #include #include "libdwP.h" #include 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; return l1->arange.addr - l2->arange.addr; } 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)