1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright 1995, 1996, 1998, 1999, 2000, 2001, 2002
3 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
26 #include <sys/param.h>
28 #include <sys/ptrace.h>
31 #include <sys/ioctl.h>
35 /***************Begin MY defs*********************/
36 static char my_registers[REGISTER_BYTES];
37 char *registers = my_registers;
38 /***************End MY defs*********************/
44 #define PTRACE_ARG3_TYPE long
45 #define PTRACE_XFER_TYPE int
49 static void initialize_arch (void);
51 /* Start an inferior process and returns its pid.
52 ALLARGS is a vector of program-name and args. */
55 create_inferior (char *program, char **allargs)
61 perror_with_name ("fork");
65 ptrace (PTRACE_TRACEME, 0, 0, 0);
67 execv (program, allargs);
69 fprintf (stderr, "Cannot exec %s: %s.\n", program,
78 /* Attach to an inferior process. */
83 if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0)
85 fprintf (stderr, "Cannot attach to process %d: %s (%d)\n", pid,
86 errno < sys_nerr ? sys_errlist[errno] : "unknown error",
95 /* Kill the inferior process. Make us have no inferior. */
100 if (inferior_pid == 0)
102 ptrace (PTRACE_KILL, inferior_pid, 0, 0);
106 /* Return nonzero if the given thread is still alive. */
108 mythread_alive (int pid)
113 /* Wait for process, returns status */
116 mywait (char *status)
122 pid = waitpid (inferior_pid, (int *)&w, 0);
124 if (pid != inferior_pid)
125 perror_with_name ("wait");
129 fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
131 return ((unsigned char) WEXITSTATUS (w));
133 else if (!WIFSTOPPED (w))
135 fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
137 return ((unsigned char) WTERMSIG (w));
140 fetch_inferior_registers (0);
143 return ((unsigned char) WSTOPSIG (w));
146 /* Resume execution of the inferior process.
147 If STEP is nonzero, single-step it.
148 If SIGNAL is nonzero, give it that signal. */
151 myresume (int step, int signal)
154 ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, inferior_pid, 1, signal);
156 perror_with_name ("ptrace");
160 #if !defined (offsetof)
161 #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
164 /* U_REGS_OFFSET is the offset of the registers within the u area. */
165 #if !defined (U_REGS_OFFSET)
166 #define U_REGS_OFFSET \
167 ptrace (PT_READ_U, inferior_pid, \
168 (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
172 #ifdef I386_GNULINUX_TARGET
173 /* This module only supports access to the general purpose registers.
174 Adjust the relevant constants accordingly.
176 FIXME: kettenis/2001-03-28: We should really use PTRACE_GETREGS to
177 get at the registers. Better yet, we should try to share code with
182 #define NUM_REGS NUM_GREGS
184 /* This stuff comes from i386-tdep.c. */
186 /* i386_register_byte[i] is the offset into the register file of the
187 start of register number i. We initialize this from
188 i386_register_raw_size. */
189 int i386_register_byte[MAX_NUM_REGS];
191 /* i386_register_raw_size[i] is the number of bytes of storage in
192 GDB's register array occupied by register i. */
193 int i386_register_raw_size[MAX_NUM_REGS] = {
208 initialize_arch (void)
210 /* Initialize the table saying where each register starts in the
216 for (i = 0; i < MAX_NUM_REGS; i++)
218 i386_register_byte[i] = offset;
219 offset += i386_register_raw_size[i];
224 /* This stuff comes from i386-linux-nat.c. */
226 /* Mapping between the general-purpose registers in `struct user'
227 format and GDB's register array layout. */
228 static int regmap[] =
236 /* Return the address of register REGNUM. BLOCKEND is the value of
237 u.u_ar0, which should point to the registers. */
240 register_u_addr (CORE_ADDR blockend, int regnum)
242 return (blockend + 4 * regmap[regnum]);
244 #elif defined(TARGET_M68K)
246 initialize_arch (void)
251 /* This table must line up with REGISTER_NAMES in tm-m68k.h */
252 static int regmap[] =
255 PT_D0, PT_D1, PT_D2, PT_D3, PT_D4, PT_D5, PT_D6, PT_D7,
256 PT_A0, PT_A1, PT_A2, PT_A3, PT_A4, PT_A5, PT_A6, PT_USP,
259 14, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15,
263 PT_FP0, PT_FP1, PT_FP2, PT_FP3, PT_FP4, PT_FP5, PT_FP6, PT_FP7,
264 PT_FPCR, PT_FPSR, PT_FPIAR
266 21, 24, 27, 30, 33, 36, 39, 42, 45, 46, 47
270 /* BLOCKEND is the value of u.u_ar0, and points to the place where GS
274 m68k_linux_register_u_addr (int blockend, int regnum)
276 return (blockend + 4 * regmap[regnum]);
278 #elif defined(IA64_GNULINUX_TARGET)
282 #include <asm/ptrace_offsets.h>
284 static int u_offsets[] =
286 /* general registers */
287 -1, /* gr0 not available; i.e, it's always zero */
319 /* gr32 through gr127 not directly available via the ptrace interface */
320 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
321 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
322 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
323 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
324 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
325 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
326 /* Floating point registers */
327 -1, -1, /* f0 and f1 not available (f0 is +0.0 and f1 is +1.0) */
454 /* predicate registers - we don't fetch these individually */
455 -1, -1, -1, -1, -1, -1, -1, -1,
456 -1, -1, -1, -1, -1, -1, -1, -1,
457 -1, -1, -1, -1, -1, -1, -1, -1,
458 -1, -1, -1, -1, -1, -1, -1, -1,
459 -1, -1, -1, -1, -1, -1, -1, -1,
460 -1, -1, -1, -1, -1, -1, -1, -1,
461 -1, -1, -1, -1, -1, -1, -1, -1,
462 -1, -1, -1, -1, -1, -1, -1, -1,
463 /* branch registers */
472 /* virtual frame pointer and virtual return address pointer */
474 /* other registers */
477 PT_CR_IPSR, /* psr */
479 /* kernel registers not visible via ptrace interface (?) */
480 -1, -1, -1, -1, -1, -1, -1, -1,
482 -1, -1, -1, -1, -1, -1, -1, -1,
488 -1, /* Not available: FCR, IA32 floating control register */
490 -1, /* Not available: EFLAG */
491 -1, /* Not available: CSD */
492 -1, /* Not available: SSD */
493 -1, /* Not available: CFLG */
494 -1, /* Not available: FSR */
495 -1, /* Not available: FIR */
496 -1, /* Not available: FDR */
504 -1, /* Not available: ITC */
505 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
506 -1, -1, -1, -1, -1, -1, -1, -1, -1,
509 -1, /* Not available: EC, the Epilog Count register */
510 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
511 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
512 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
513 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
514 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
515 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
517 /* nat bits - not fetched directly; instead we obtain these bits from
518 either rnat or unat or from memory. */
519 -1, -1, -1, -1, -1, -1, -1, -1,
520 -1, -1, -1, -1, -1, -1, -1, -1,
521 -1, -1, -1, -1, -1, -1, -1, -1,
522 -1, -1, -1, -1, -1, -1, -1, -1,
523 -1, -1, -1, -1, -1, -1, -1, -1,
524 -1, -1, -1, -1, -1, -1, -1, -1,
525 -1, -1, -1, -1, -1, -1, -1, -1,
526 -1, -1, -1, -1, -1, -1, -1, -1,
527 -1, -1, -1, -1, -1, -1, -1, -1,
528 -1, -1, -1, -1, -1, -1, -1, -1,
529 -1, -1, -1, -1, -1, -1, -1, -1,
530 -1, -1, -1, -1, -1, -1, -1, -1,
531 -1, -1, -1, -1, -1, -1, -1, -1,
532 -1, -1, -1, -1, -1, -1, -1, -1,
533 -1, -1, -1, -1, -1, -1, -1, -1,
534 -1, -1, -1, -1, -1, -1, -1, -1,
538 ia64_register_u_addr (int blockend, int regnum)
542 if (regnum < 0 || regnum >= NUM_REGS)
543 error ("Invalid register number %d.", regnum);
545 addr = u_offsets[regnum];
553 initialize_arch (void)
558 #elif defined(ARM_GNULINUX_TARGET)
559 int arm_register_u_addr(blockend, regnum)
563 return blockend + REGISTER_BYTE(regnum);
573 register_addr (int regno, CORE_ADDR blockend)
577 if (regno < 0 || regno >= NUM_REGS)
578 error ("Invalid register number %d.", regno);
580 REGISTER_U_ADDR (addr, blockend, regno);
585 /* Fetch one register. */
588 fetch_register (int regno)
593 /* Offset of registers within the u area. */
596 offset = U_REGS_OFFSET;
598 regaddr = register_addr (regno, offset);
599 for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
602 *(PTRACE_XFER_TYPE *) ®isters[REGISTER_BYTE (regno) + i] =
603 ptrace (PTRACE_PEEKUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, 0);
604 regaddr += sizeof (PTRACE_XFER_TYPE);
607 /* Warning, not error, in case we are attached; sometimes the
608 kernel doesn't let us at the registers. */
609 char *err = strerror (errno);
610 char *msg = alloca (strlen (err) + 128);
611 sprintf (msg, "reading register %d: %s", regno, err);
619 /* Fetch all registers, or just one, from the child process. */
622 fetch_inferior_registers (int regno)
624 if (regno == -1 || regno == 0)
625 for (regno = 0; regno < NUM_REGS - NUM_FREGS; regno++)
626 fetch_register (regno);
628 fetch_register (regno);
631 /* Store our register values back into the inferior.
632 If REGNO is -1, do this for all registers.
633 Otherwise, REGNO specifies which register (so we can save time). */
636 store_inferior_registers (int regno)
640 unsigned int offset = U_REGS_OFFSET;
645 if (CANNOT_STORE_REGISTER (regno))
648 regaddr = register_addr (regno, offset);
651 if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
653 scratch = *(int *) ®isters[REGISTER_BYTE (regno)] | 0x3;
654 ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
658 /* Error, even if attached. Failing to write these two
659 registers is pretty serious. */
660 sprintf (buf, "writing register number %d", regno);
661 perror_with_name (buf);
666 for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
669 ptrace (PTRACE_POKEUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
670 *(int *) ®isters[REGISTER_BYTE (regno) + i]);
673 /* Warning, not error, in case we are attached; sometimes the
674 kernel doesn't let us at the registers. */
675 char *err = strerror (errno);
676 char *msg = alloca (strlen (err) + 128);
677 sprintf (msg, "writing register %d: %s",
682 regaddr += sizeof (int);
686 for (regno = 0; regno < NUM_REGS - NUM_FREGS; regno++)
687 store_inferior_registers (regno);
690 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
691 in the NEW_SUN_PTRACE case.
692 It ought to be straightforward. But it appears that writing did
693 not write the data that I specified. I cannot understand where
694 it got the data that it actually did write. */
696 /* Copy LEN bytes from inferior's memory starting at MEMADDR
697 to debugger memory starting at MYADDR. */
700 read_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
703 /* Round starting address down to longword boundary. */
704 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
705 /* Round ending address up; get number of longwords that makes. */
707 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
708 / sizeof (PTRACE_XFER_TYPE);
709 /* Allocate buffer of that many longwords. */
710 register PTRACE_XFER_TYPE *buffer
711 = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
713 /* Read all the longwords */
714 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
716 buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, 0);
719 /* Copy appropriate bytes out of the buffer. */
720 memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), len);
723 /* Copy LEN bytes of data from debugger memory at MYADDR
724 to inferior's memory at MEMADDR.
725 On failure (cannot write the inferior)
726 returns the value of errno. */
729 write_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
732 /* Round starting address down to longword boundary. */
733 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
734 /* Round ending address up; get number of longwords that makes. */
736 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) / sizeof (PTRACE_XFER_TYPE);
737 /* Allocate buffer of that many longwords. */
738 register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
741 /* Fill start and end extra bytes of buffer with existing memory data. */
743 buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid,
744 (PTRACE_ARG3_TYPE) addr, 0);
749 = ptrace (PTRACE_PEEKTEXT, inferior_pid,
750 (PTRACE_ARG3_TYPE) (addr + (count - 1)
751 * sizeof (PTRACE_XFER_TYPE)),
755 /* Copy data to be written over corresponding part of buffer */
757 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), myaddr, len);
759 /* Write the entire buffer. */
761 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
764 ptrace (PTRACE_POKETEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, buffer[i]);
773 initialize_low (void)