/*- * Copyright (c) 2007 John Birrell (jb@freebsd.org) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ #include #include "_libdwarf.h" static int64_t dwarf_decode_sleb128(uint8_t **dp) { int64_t ret = 0; uint8_t b; int shift = 0; uint8_t *src = *dp; do { b = *src++; ret |= ((b & 0x7f) << shift); shift += 7; } while ((b & 0x80) != 0); if (shift < 64 && (b & 0x40) != 0) ret |= (-1 << shift); *dp = src; return ret; } static uint64_t dwarf_decode_uleb128(uint8_t **dp) { uint64_t ret = 0; uint8_t b; int shift = 0; uint8_t *src = *dp; do { b = *src++; ret |= ((b & 0x7f) << shift); shift += 7; } while ((b & 0x80) != 0); *dp = src; return ret; } /* * Given an array of bytes of length 'len' representing a * DWARF expression, compute the number of operations based * on there being one byte describing the operation and * zero or more bytes of operands as defined in the standard * for each operation type. */ int dwarf_op_num(uint8_t pointer_size, uint8_t *p, int len) { int count = 0; int64_t sval; uint64_t uval; uint8_t *last = p + len; /* * Process each byte. If an error occurs, then the * count will be set to -1. */ while (p < last && count >= 0) { count++; switch (*p++) { /* Operations with no operands. */ case DW_OP_deref: case DW_OP_reg0: case DW_OP_reg1: case DW_OP_reg2: case DW_OP_reg3: case DW_OP_reg4: case DW_OP_reg5: case DW_OP_reg6: case DW_OP_reg7: case DW_OP_reg8: case DW_OP_reg9: case DW_OP_reg10: case DW_OP_reg11: case DW_OP_reg12: case DW_OP_reg13: case DW_OP_reg14: case DW_OP_reg15: case DW_OP_reg16: case DW_OP_reg17: case DW_OP_reg18: case DW_OP_reg19: case DW_OP_reg20: case DW_OP_reg21: case DW_OP_reg22: case DW_OP_reg23: case DW_OP_reg24: case DW_OP_reg25: case DW_OP_reg26: case DW_OP_reg27: case DW_OP_reg28: case DW_OP_reg29: case DW_OP_reg30: case DW_OP_reg31: case DW_OP_lit0: case DW_OP_lit1: case DW_OP_lit2: case DW_OP_lit3: case DW_OP_lit4: case DW_OP_lit5: case DW_OP_lit6: case DW_OP_lit7: case DW_OP_lit8: case DW_OP_lit9: case DW_OP_lit10: case DW_OP_lit11: case DW_OP_lit12: case DW_OP_lit13: case DW_OP_lit14: case DW_OP_lit15: case DW_OP_lit16: case DW_OP_lit17: case DW_OP_lit18: case DW_OP_lit19: case DW_OP_lit20: case DW_OP_lit21: case DW_OP_lit22: case DW_OP_lit23: case DW_OP_lit24: case DW_OP_lit25: case DW_OP_lit26: case DW_OP_lit27: case DW_OP_lit28: case DW_OP_lit29: case DW_OP_lit30: case DW_OP_lit31: case DW_OP_dup: case DW_OP_drop: case DW_OP_over: case DW_OP_swap: case DW_OP_rot: case DW_OP_xderef: case DW_OP_abs: case DW_OP_and: case DW_OP_div: case DW_OP_minus: case DW_OP_mod: case DW_OP_mul: case DW_OP_neg: case DW_OP_not: case DW_OP_or: case DW_OP_plus: case DW_OP_shl: case DW_OP_shr: case DW_OP_shra: case DW_OP_xor: case DW_OP_eq: case DW_OP_ge: case DW_OP_gt: case DW_OP_le: case DW_OP_lt: case DW_OP_ne: case DW_OP_nop: break; /* Operations with 1-byte operands. */ case DW_OP_const1u: case DW_OP_const1s: case DW_OP_pick: case DW_OP_deref_size: case DW_OP_xderef_size: p++; break; /* Operations with 2-byte operands. */ case DW_OP_const2u: case DW_OP_const2s: case DW_OP_bra: case DW_OP_skip: p += 2; break; /* Operations with 4-byte operands. */ case DW_OP_const4u: case DW_OP_const4s: p += 4; break; /* Operations with 8-byte operands. */ case DW_OP_const8u: case DW_OP_const8s: p += 8; break; /* Operations with an unsigned LEB128 operand. */ case DW_OP_constu: case DW_OP_plus_uconst: case DW_OP_regx: case DW_OP_piece: uval = dwarf_decode_uleb128(&p); break; /* Operations with a signed LEB128 operand. */ case DW_OP_consts: case DW_OP_breg0: case DW_OP_breg1: case DW_OP_breg2: case DW_OP_breg3: case DW_OP_breg4: case DW_OP_breg5: case DW_OP_breg6: case DW_OP_breg7: case DW_OP_breg8: case DW_OP_breg9: case DW_OP_breg10: case DW_OP_breg11: case DW_OP_breg12: case DW_OP_breg13: case DW_OP_breg14: case DW_OP_breg15: case DW_OP_breg16: case DW_OP_breg17: case DW_OP_breg18: case DW_OP_breg19: case DW_OP_breg20: case DW_OP_breg21: case DW_OP_breg22: case DW_OP_breg23: case DW_OP_breg24: case DW_OP_breg25: case DW_OP_breg26: case DW_OP_breg27: case DW_OP_breg28: case DW_OP_breg29: case DW_OP_breg30: case DW_OP_breg31: case DW_OP_fbreg: sval = dwarf_decode_sleb128(&p); break; /* * Operations with an unsigned LEB128 operand * followed by a signed LEB128 operand. */ case DW_OP_bregx: uval = dwarf_decode_uleb128(&p); sval = dwarf_decode_sleb128(&p); break; /* Target address size operand. */ case DW_OP_addr: p += pointer_size; break; /* All other operations cause an error. */ default: count = -1; break; } } return count; } static int dwarf_loc_fill(Dwarf_Locdesc *lbuf, uint8_t pointer_size, uint8_t *p, int len) { int count = 0; int ret = DWARF_E_NONE; uint64_t operand1; uint64_t operand2; uint8_t *last = p + len; /* * Process each byte. If an error occurs, then the * count will be set to -1. */ while (p < last && ret == DWARF_E_NONE) { operand1 = 0; operand2 = 0; lbuf->ld_s[count].lr_atom = *p; switch (*p++) { /* Operations with no operands. */ case DW_OP_deref: case DW_OP_reg0: case DW_OP_reg1: case DW_OP_reg2: case DW_OP_reg3: case DW_OP_reg4: case DW_OP_reg5: case DW_OP_reg6: case DW_OP_reg7: case DW_OP_reg8: case DW_OP_reg9: case DW_OP_reg10: case DW_OP_reg11: case DW_OP_reg12: case DW_OP_reg13: case DW_OP_reg14: case DW_OP_reg15: case DW_OP_reg16: case DW_OP_reg17: case DW_OP_reg18: case DW_OP_reg19: case DW_OP_reg20: case DW_OP_reg21: case DW_OP_reg22: case DW_OP_reg23: case DW_OP_reg24: case DW_OP_reg25: case DW_OP_reg26: case DW_OP_reg27: case DW_OP_reg28: case DW_OP_reg29: case DW_OP_reg30: case DW_OP_reg31: case DW_OP_lit0: case DW_OP_lit1: case DW_OP_lit2: case DW_OP_lit3: case DW_OP_lit4: case DW_OP_lit5: case DW_OP_lit6: case DW_OP_lit7: case DW_OP_lit8: case DW_OP_lit9: case DW_OP_lit10: case DW_OP_lit11: case DW_OP_lit12: case DW_OP_lit13: case DW_OP_lit14: case DW_OP_lit15: case DW_OP_lit16: case DW_OP_lit17: case DW_OP_lit18: case DW_OP_lit19: case DW_OP_lit20: case DW_OP_lit21: case DW_OP_lit22: case DW_OP_lit23: case DW_OP_lit24: case DW_OP_lit25: case DW_OP_lit26: case DW_OP_lit27: case DW_OP_lit28: case DW_OP_lit29: case DW_OP_lit30: case DW_OP_lit31: case DW_OP_dup: case DW_OP_drop: case DW_OP_over: case DW_OP_swap: case DW_OP_rot: case DW_OP_xderef: case DW_OP_abs: case DW_OP_and: case DW_OP_div: case DW_OP_minus: case DW_OP_mod: case DW_OP_mul: case DW_OP_neg: case DW_OP_not: case DW_OP_or: case DW_OP_plus: case DW_OP_shl: case DW_OP_shr: case DW_OP_shra: case DW_OP_xor: case DW_OP_eq: case DW_OP_ge: case DW_OP_gt: case DW_OP_le: case DW_OP_lt: case DW_OP_ne: case DW_OP_nop: break; /* Operations with 1-byte operands. */ case DW_OP_const1u: case DW_OP_const1s: case DW_OP_pick: case DW_OP_deref_size: case DW_OP_xderef_size: operand1 = *p++; break; /* Operations with 2-byte operands. */ case DW_OP_const2u: case DW_OP_const2s: case DW_OP_bra: case DW_OP_skip: p += 2; break; /* Operations with 4-byte operands. */ case DW_OP_const4u: case DW_OP_const4s: p += 4; break; /* Operations with 8-byte operands. */ case DW_OP_const8u: case DW_OP_const8s: p += 8; break; /* Operations with an unsigned LEB128 operand. */ case DW_OP_constu: case DW_OP_plus_uconst: case DW_OP_regx: case DW_OP_piece: operand1 = dwarf_decode_uleb128(&p); break; /* Operations with a signed LEB128 operand. */ case DW_OP_consts: case DW_OP_breg0: case DW_OP_breg1: case DW_OP_breg2: case DW_OP_breg3: case DW_OP_breg4: case DW_OP_breg5: case DW_OP_breg6: case DW_OP_breg7: case DW_OP_breg8: case DW_OP_breg9: case DW_OP_breg10: case DW_OP_breg11: case DW_OP_breg12: case DW_OP_breg13: case DW_OP_breg14: case DW_OP_breg15: case DW_OP_breg16: case DW_OP_breg17: case DW_OP_breg18: case DW_OP_breg19: case DW_OP_breg20: case DW_OP_breg21: case DW_OP_breg22: case DW_OP_breg23: case DW_OP_breg24: case DW_OP_breg25: case DW_OP_breg26: case DW_OP_breg27: case DW_OP_breg28: case DW_OP_breg29: case DW_OP_breg30: case DW_OP_breg31: case DW_OP_fbreg: operand1 = dwarf_decode_sleb128(&p); break; /* * Operations with an unsigned LEB128 operand * followed by a signed LEB128 operand. */ case DW_OP_bregx: operand1 = dwarf_decode_uleb128(&p); operand2 = dwarf_decode_sleb128(&p); break; /* Target address size operand. */ case DW_OP_addr: p += pointer_size; break; /* All other operations cause an error. */ default: break; } lbuf->ld_s[count].lr_number = operand1; lbuf->ld_s[count].lr_number2 = operand2; count++; } return ret; } int dwarf_locdesc(Dwarf_Die die, uint64_t attr, Dwarf_Locdesc **llbuf, Dwarf_Signed *lenp, Dwarf_Error *err) { Dwarf_AttrValue av; Dwarf_Locdesc *lbuf; int num; int ret = DWARF_E_NONE; if (err == NULL) return DWARF_E_ERROR; if (die == NULL || llbuf == NULL || lenp == NULL) { DWARF_SET_ERROR(err, DWARF_E_ARGUMENT); return DWARF_E_ARGUMENT; } if ((av = dwarf_attrval_find(die, attr)) == NULL) { DWARF_SET_ERROR(err, DWARF_E_NO_ENTRY); ret = DWARF_E_NO_ENTRY; } else if ((lbuf = calloc(sizeof(Dwarf_Locdesc), 1)) == NULL) { DWARF_SET_ERROR(err, DWARF_E_MEMORY); ret = DWARF_E_MEMORY; } else { *lenp = 0; switch (av->av_form) { case DW_FORM_block: case DW_FORM_block1: case DW_FORM_block2: case DW_FORM_block4: /* Compute the number of locations: */ if ((num = dwarf_op_num(die->die_cu->cu_pointer_size, av->u[1].u8p, av->u[0].u64)) < 0) { DWARF_SET_ERROR(err, DWARF_E_INVALID_EXPR); ret = DWARF_E_INVALID_EXPR; /* Allocate an array of location structures. */ } else if ((lbuf->ld_s = calloc(sizeof(Dwarf_Loc), num)) == NULL) { DWARF_SET_ERROR(err, DWARF_E_MEMORY); ret = DWARF_E_MEMORY; /* Fill the array of location structures. */ } else if ((ret = dwarf_loc_fill(lbuf, die->die_cu->cu_pointer_size, av->u[1].u8p, av->u[0].u64)) != DWARF_E_NONE) { free(lbuf->ld_s); } else /* Only one descriptor is returned. */ *lenp = 1; break; default: printf("%s(%d): form %s not handled\n",__func__, __LINE__,get_form_desc(av->av_form)); DWARF_SET_ERROR(err, DWARF_E_NOT_IMPLEMENTED); ret = DWARF_E_ERROR; } if (ret == DWARF_E_NONE) { *llbuf = lbuf; } else free(lbuf); } return ret; } int dwarf_locdesc_free(Dwarf_Locdesc *lbuf, Dwarf_Error *err) { if (err == NULL) return DWARF_E_ERROR; if (lbuf == NULL) { DWARF_SET_ERROR(err, DWARF_E_ARGUMENT); return DWARF_E_ARGUMENT; } if (lbuf->ld_s != NULL) free(lbuf->ld_s); free(lbuf); return DWARF_E_NONE; }