1/* Low level DECstation interface to ptrace, for GDB when running native. 2 Copyright 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1999, 2000, 2001 3 Free Software Foundation, Inc. 4 Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU 5 and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin. 6 7 This file is part of GDB. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 59 Temple Place - Suite 330, 22 Boston, MA 02111-1307, USA. */ 23 24#include "defs.h" 25#include "inferior.h" 26#include "gdbcore.h" 27#include "regcache.h" 28#include <sys/ptrace.h> 29#include <sys/types.h> 30#include <sys/param.h> 31#include <sys/user.h> 32#undef JB_S0 33#undef JB_S1 34#undef JB_S2 35#undef JB_S3 36#undef JB_S4 37#undef JB_S5 38#undef JB_S6 39#undef JB_S7 40#undef JB_SP 41#undef JB_S8 42#undef JB_PC 43#undef JB_SR 44#undef NJBREGS 45#include <setjmp.h> /* For JB_XXX. */ 46 47/* Size of elements in jmpbuf */ 48 49#define JB_ELEMENT_SIZE 4 50 51/* Map gdb internal register number to ptrace ``address''. 52 These ``addresses'' are defined in DECstation <sys/ptrace.h> */ 53 54static int 55register_ptrace_addr (int regno) 56{ 57 return (regno < 32 ? GPR_BASE + regno 58 : regno == mips_regnum (current_gdbarch)->pc ? PC 59 : regno == mips_regnum (current_gdbarch)->cause ? CAUSE 60 : regno == mips_regnum (current_gdbarch)->hi ? MMHI 61 : regno == mips_regnum (current_gdbarch)->lo ? MMLO 62 : regno == mips_regnum (current_gdbarch)->fp_control_status ? FPC_CSR 63 : regno == mips_regnum (current_gdbarch)->fp_implementation_revision ? FPC_EIR 64 : regno >= FP0_REGNUM ? FPR_BASE + (regno - FP0_REGNUM) 65 : 0); 66} 67 68static void fetch_core_registers (char *, unsigned, int, CORE_ADDR); 69 70/* Get all registers from the inferior */ 71 72void 73fetch_inferior_registers (int regno) 74{ 75 unsigned int regaddr; 76 char buf[MAX_REGISTER_SIZE]; 77 int i; 78 char zerobuf[MAX_REGISTER_SIZE]; 79 memset (zerobuf, 0, MAX_REGISTER_SIZE); 80 81 deprecated_registers_fetched (); 82 83 for (regno = 1; regno < NUM_REGS; regno++) 84 { 85 regaddr = register_ptrace_addr (regno); 86 for (i = 0; i < DEPRECATED_REGISTER_RAW_SIZE (regno); i += sizeof (int)) 87 { 88 *(int *) &buf[i] = ptrace (PT_READ_U, PIDGET (inferior_ptid), 89 (PTRACE_ARG3_TYPE) regaddr, 0); 90 regaddr += sizeof (int); 91 } 92 supply_register (regno, buf); 93 } 94 95 supply_register (ZERO_REGNUM, zerobuf); 96 /* Frame ptr reg must appear to be 0; it is faked by stack handling code. */ 97 supply_register (DEPRECATED_FP_REGNUM, zerobuf); 98} 99 100/* Store our register values back into the inferior. 101 If REGNO is -1, do this for all registers. 102 Otherwise, REGNO specifies which register (so we can save time). */ 103 104void 105store_inferior_registers (int regno) 106{ 107 unsigned int regaddr; 108 char buf[80]; 109 110 if (regno > 0) 111 { 112 if (regno == ZERO_REGNUM || regno == PS_REGNUM 113 || regno == mips_regnum (current_gdbarch)->badvaddr 114 || regno == mips_regnum (current_gdbarch)->cause 115 || regno == mips_regnum (current_gdbarch)->fp_implementation_revision 116 || regno == DEPRECATED_FP_REGNUM 117 || (regno >= FIRST_EMBED_REGNUM && regno <= LAST_EMBED_REGNUM)) 118 return; 119 regaddr = register_ptrace_addr (regno); 120 errno = 0; 121 ptrace (PT_WRITE_U, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) regaddr, 122 read_register (regno)); 123 if (errno != 0) 124 { 125 sprintf (buf, "writing register number %d", regno); 126 perror_with_name (buf); 127 } 128 } 129 else 130 { 131 for (regno = 0; regno < NUM_REGS; regno++) 132 store_inferior_registers (regno); 133 } 134} 135 136 137/* Figure out where the longjmp will land. 138 We expect the first arg to be a pointer to the jmp_buf structure from which 139 we extract the pc (JB_PC) that we will land at. The pc is copied into PC. 140 This routine returns true on success. */ 141 142int 143get_longjmp_target (CORE_ADDR *pc) 144{ 145 CORE_ADDR jb_addr; 146 char *buf; 147 148 buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT); 149 jb_addr = read_register (A0_REGNUM); 150 151 if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf, 152 TARGET_PTR_BIT / TARGET_CHAR_BIT)) 153 return 0; 154 155 *pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); 156 157 return 1; 158} 159 160/* Extract the register values out of the core file and store 161 them where `read_register' will find them. 162 163 CORE_REG_SECT points to the register values themselves, read into memory. 164 CORE_REG_SIZE is the size of that area. 165 WHICH says which set of registers we are handling (0 = int, 2 = float 166 on machines where they are discontiguous). 167 REG_ADDR is the offset from u.u_ar0 to the register values relative to 168 core_reg_sect. This is used with old-fashioned core files to 169 locate the registers in a large upage-plus-stack ".reg" section. 170 Original upage address X is at location core_reg_sect+x+reg_addr. 171 */ 172 173static void 174fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which, 175 CORE_ADDR reg_addr) 176{ 177 int regno; 178 unsigned int addr; 179 int bad_reg = -1; 180 reg_ptr = -reg_addr; /* Original u.u_ar0 is -reg_addr. */ 181 182 char zerobuf[MAX_REGISTER_SIZE]; 183 memset (zerobuf, 0, MAX_REGISTER_SIZE); 184 185 186 /* If u.u_ar0 was an absolute address in the core file, relativize it now, 187 so we can use it as an offset into core_reg_sect. When we're done, 188 "register 0" will be at core_reg_sect+reg_ptr, and we can use 189 register_addr to offset to the other registers. If this is a modern 190 core file without a upage, reg_ptr will be zero and this is all a big 191 NOP. */ 192 if (reg_ptr > core_reg_size) 193#ifdef KERNEL_U_ADDR 194 reg_ptr -= KERNEL_U_ADDR; 195#else 196 error ("Old mips core file can't be processed on this machine."); 197#endif 198 199 for (regno = 0; regno < NUM_REGS; regno++) 200 { 201 addr = register_addr (regno, reg_ptr); 202 if (addr >= core_reg_size) 203 { 204 if (bad_reg < 0) 205 bad_reg = regno; 206 } 207 else 208 { 209 supply_register (regno, core_reg_sect + addr); 210 } 211 } 212 if (bad_reg >= 0) 213 { 214 error ("Register %s not found in core file.", REGISTER_NAME (bad_reg)); 215 } 216 supply_register (ZERO_REGNUM, zerobuf); 217 /* Frame ptr reg must appear to be 0; it is faked by stack handling code. */ 218 supply_register (DEPRECATED_FP_REGNUM, zerobuf); 219} 220 221/* Return the address in the core dump or inferior of register REGNO. 222 BLOCKEND is the address of the end of the user structure. */ 223 224CORE_ADDR 225register_addr (int regno, CORE_ADDR blockend) 226{ 227 CORE_ADDR addr; 228 229 if (regno < 0 || regno >= NUM_REGS) 230 error ("Invalid register number %d.", regno); 231 232 REGISTER_U_ADDR (addr, blockend, regno); 233 234 return addr; 235} 236 237 238/* Register that we are able to handle mips core file formats. 239 FIXME: is this really bfd_target_unknown_flavour? */ 240 241static struct core_fns mips_core_fns = 242{ 243 bfd_target_unknown_flavour, /* core_flavour */ 244 default_check_format, /* check_format */ 245 default_core_sniffer, /* core_sniffer */ 246 fetch_core_registers, /* core_read_registers */ 247 NULL /* next */ 248}; 249 250void 251_initialize_core_mips (void) 252{ 253 add_core_fns (&mips_core_fns); 254} 255