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-rw-r--r--gdb/infptrace.c397
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diff --git a/gdb/infptrace.c b/gdb/infptrace.c
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+/* Low level Unix child interface to ptrace, for GDB when running under Unix.
+ Copyright (C) 1988, 1989, 1990, 1991 Free Software Foundation, Inc.
+
+This file is part of GDB.
+
+GDB is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 1, or (at your option)
+any later version.
+
+GDB 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 a copy of the GNU General Public License
+along with GDB; see the file COPYING. If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <stdio.h>
+#include "defs.h"
+#include "param.h"
+#include "frame.h"
+#include "inferior.h"
+#include "target.h"
+
+#ifdef USG
+#include <sys/types.h>
+#endif
+
+#include <sys/param.h>
+#include <sys/dir.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <sys/ptrace.h>
+#if !defined (PT_KILL)
+#define PT_KILL 8
+#define PT_STEP 9
+#define PT_CONTINUE 7
+#define PT_READ_U 3
+#define PT_WRITE_U 6
+#define PT_READ_I 1
+#define PT_WRITE_I 4
+/* The Following Change is for a Sun */
+#define PT_WRITE_D 4
+#endif /* No PT_KILL. */
+
+#ifndef PT_ATTACH
+#define PT_ATTACH PTRACE_ATTACH
+#endif
+#ifndef PT_DETACH
+#define PT_DETACH PTRACE_DETACH
+#endif
+
+#include "gdbcore.h"
+#include <sys/user.h> /* After a.out.h */
+#include <sys/file.h>
+#include <sys/stat.h>
+
+/* This function simply calls ptrace with the given arguments.
+ It exists so that all calls to ptrace are isolated in this
+ machine-dependent file. */
+int
+call_ptrace (request, pid, addr, data)
+ int request, pid, *addr, data;
+{
+ return ptrace (request, pid, addr, data);
+}
+
+#ifdef DEBUG_PTRACE
+/* For the rest of the file, use an extra level of indirection */
+/* This lets us breakpoint usefully on call_ptrace. */
+#define ptrace call_ptrace
+#endif
+
+/* This is used when GDB is exiting. It gives less chance of error.*/
+
+void
+kill_inferior_fast ()
+{
+ if (inferior_pid == 0)
+ return;
+ ptrace (PT_KILL, inferior_pid, 0, 0);
+ wait ((int *)0);
+}
+
+void
+kill_inferior (args, from_tty)
+ char *args;
+ int from_tty;
+{
+ kill_inferior_fast ();
+ target_mourn_inferior ();
+}
+
+/* Resume execution of the inferior process.
+ If STEP is nonzero, single-step it.
+ If SIGNAL is nonzero, give it that signal. */
+
+void
+child_resume (step, signal)
+ int step;
+ int signal;
+{
+ errno = 0;
+ /* An address of (int *)1 tells it to continue from where it was.
+ (If GDB wanted it to start some other way, we have already written
+ a new PC value to the child.) */
+ if (step)
+ {
+#if defined (NO_SINGLE_STEP)
+ single_step (signal);
+#else /* Have single step. */
+ ptrace (PT_STEP, inferior_pid, (int *)1, signal);
+#endif /* Have single step. */
+ }
+ else
+ ptrace (PT_CONTINUE, inferior_pid, (int *)1, signal);
+ if (errno)
+ perror_with_name ("ptrace");
+}
+
+#ifdef ATTACH_DETACH
+/* Nonzero if we are debugging an attached process rather than
+ an inferior. */
+extern int attach_flag;
+
+/* Start debugging the process whose number is PID. */
+int
+attach (pid)
+ int pid;
+{
+ errno = 0;
+ ptrace (PT_ATTACH, pid, 0, 0);
+ if (errno)
+ perror_with_name ("ptrace");
+ attach_flag = 1;
+ return pid;
+}
+
+/* Stop debugging the process whose number is PID
+ and continue it with signal number SIGNAL.
+ SIGNAL = 0 means just continue it. */
+
+void
+detach (signal)
+ int signal;
+{
+ errno = 0;
+ ptrace (PT_DETACH, inferior_pid, 1, signal);
+ if (errno)
+ perror_with_name ("ptrace");
+ attach_flag = 0;
+}
+#endif /* ATTACH_DETACH */
+
+#if !defined (FETCH_INFERIOR_REGISTERS)
+
+/* KERNEL_U_ADDR is the amount to subtract from u.u_ar0
+ to get the offset in the core file of the register values. */
+#if defined (KERNEL_U_ADDR_BSD)
+/* Get kernel_u_addr using BSD-style nlist(). */
+CORE_ADDR kernel_u_addr;
+
+void
+_initialize_kernel_u_addr ()
+{
+ struct nlist names[2];
+
+ names[0].n_un.n_name = "_u";
+ names[1].n_un.n_name = NULL;
+ if (nlist ("/vmunix", names) == 0)
+ kernel_u_addr = names[0].n_value;
+ else
+ fatal ("Unable to get kernel u area address.");
+}
+#endif /* KERNEL_U_ADDR_BSD. */
+
+#if defined (KERNEL_U_ADDR_HPUX)
+/* Get kernel_u_addr using HPUX-style nlist(). */
+CORE_ADDR kernel_u_addr;
+
+struct hpnlist {
+ char * n_name;
+ long n_value;
+ unsigned char n_type;
+ unsigned char n_length;
+ short n_almod;
+ short n_unused;
+};
+static struct hpnlist nl[] = {{ "_u", -1, }, { (char *) 0, }};
+
+/* read the value of the u area from the hp-ux kernel */
+void _initialize_kernel_u_addr ()
+{
+ struct user u;
+ nlist ("/hp-ux", &nl);
+ kernel_u_addr = nl[0].n_value;
+}
+#endif /* KERNEL_U_ADDR_HPUX. */
+
+#if !defined (offsetof)
+#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
+#endif
+
+/* U_REGS_OFFSET is the offset of the registers within the u area. */
+#if !defined (U_REGS_OFFSET)
+#define U_REGS_OFFSET \
+ ptrace (PT_READ_U, inferior_pid, \
+ (int *)(offsetof (struct user, u_ar0)), 0) - KERNEL_U_ADDR
+#endif
+
+/* Fetch one register. */
+static void
+fetch_register (regno)
+ int regno;
+{
+ register unsigned int regaddr;
+ char buf[MAX_REGISTER_RAW_SIZE];
+ register int i;
+
+ /* Offset of registers within the u area. */
+ unsigned int offset = U_REGS_OFFSET;
+
+ regaddr = register_addr (regno, offset);
+ for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
+ {
+ *(int *) &buf[i] = ptrace (PT_READ_U, inferior_pid, (int *)regaddr, 0);
+ regaddr += sizeof (int);
+ }
+ supply_register (regno, buf);
+}
+
+/* Fetch all registers, or just one, from the child process.
+ We should check for errors, but we don't. FIXME. */
+
+int
+fetch_inferior_registers (regno)
+ int regno;
+{
+ if (regno == -1)
+ for (regno = 0; regno < NUM_REGS; regno++)
+ fetch_register (regno);
+ else
+ fetch_register (regno);
+ return 0;
+}
+
+/* Registers we shouldn't try to store. */
+#if !defined (CANNOT_STORE_REGISTER)
+#define CANNOT_STORE_REGISTER(regno) 0
+#endif
+
+/* Store our register values back into the inferior.
+ If REGNO is -1, do this for all registers.
+ Otherwise, REGNO specifies which register (so we can save time). */
+
+int
+store_inferior_registers (regno)
+ int regno;
+{
+ register unsigned int regaddr;
+ char buf[80];
+ extern char registers[];
+ register int i;
+ int result = 0;
+
+ unsigned int offset = U_REGS_OFFSET;
+
+ if (regno >= 0)
+ {
+ regaddr = register_addr (regno, offset);
+ for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
+ {
+ errno = 0;
+ ptrace (PT_WRITE_U, inferior_pid, (int *)regaddr,
+ *(int *) &registers[REGISTER_BYTE (regno) + i]);
+ if (errno != 0)
+ {
+ sprintf (buf, "writing register number %d(%d)", regno, i);
+ perror_with_name (buf);
+ result = -1;
+ }
+ regaddr += sizeof(int);
+ }
+ }
+ else
+ {
+ for (regno = 0; regno < NUM_REGS; regno++)
+ {
+ if (CANNOT_STORE_REGISTER (regno))
+ continue;
+ regaddr = register_addr (regno, offset);
+ for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
+ {
+ errno = 0;
+ ptrace (PT_WRITE_U, inferior_pid, (int *)regaddr,
+ *(int *) &registers[REGISTER_BYTE (regno) + i]);
+ if (errno != 0)
+ {
+ sprintf (buf, "writing register number %d(%d)", regno, i);
+ perror_with_name (buf);
+ result = -1;
+ }
+ regaddr += sizeof(int);
+ }
+ }
+ }
+ return result;
+}
+#endif /* !defined (FETCH_INFERIOR_REGISTERS). */
+
+/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
+ in the NEW_SUN_PTRACE case.
+ It ought to be straightforward. But it appears that writing did
+ not write the data that I specified. I cannot understand where
+ it got the data that it actually did write. */
+
+/* Copy LEN bytes to or from inferior's memory starting at MEMADDR
+ to debugger memory starting at MYADDR. Copy to inferior if
+ WRITE is nonzero.
+
+ Returns the length copied, which is either the LEN argument or zero.
+ This xfer function does not do partial moves, since child_ops
+ doesn't allow memory operations to cross below us in the target stack
+ anyway. */
+
+int
+child_xfer_memory (memaddr, myaddr, len, write)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+ int write;
+{
+ register int i;
+ /* Round starting address down to longword boundary. */
+ register CORE_ADDR addr = memaddr & - sizeof (int);
+ /* Round ending address up; get number of longwords that makes. */
+ register int count
+ = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
+ /* Allocate buffer of that many longwords. */
+ register int *buffer = (int *) alloca (count * sizeof (int));
+
+ if (write)
+ {
+ /* Fill start and end extra bytes of buffer with existing memory data. */
+
+ if (addr != memaddr || len < (int)sizeof (int)) {
+ /* Need part of initial word -- fetch it. */
+ buffer[0] = ptrace (PT_READ_I, inferior_pid, (int *)addr, 0);
+ }
+
+ if (count > 1) /* FIXME, avoid if even boundary */
+ {
+ buffer[count - 1]
+ = ptrace (PT_READ_I, inferior_pid,
+ (int *)(addr + (count - 1) * sizeof (int)), 0);
+ }
+
+ /* Copy data to be written over corresponding part of buffer */
+
+ bcopy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
+
+ /* Write the entire buffer. */
+
+ for (i = 0; i < count; i++, addr += sizeof (int))
+ {
+ errno = 0;
+ ptrace (PT_WRITE_D, inferior_pid, (int *)addr, buffer[i]);
+ if (errno)
+ {
+ /* Using the appropriate one (I or D) is necessary for
+ Gould NP1, at least. */
+ errno = 0;
+ ptrace (PT_WRITE_I, inferior_pid, (int *)addr, buffer[i]);
+ }
+ if (errno)
+ return 0;
+ }
+ }
+ else
+ {
+ /* Read all the longwords */
+ for (i = 0; i < count; i++, addr += sizeof (int))
+ {
+ errno = 0;
+ buffer[i] = ptrace (PT_READ_I, inferior_pid, (int *)addr, 0);
+ if (errno)
+ return 0;
+ QUIT;
+ }
+
+ /* Copy appropriate bytes out of the buffer. */
+ bcopy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
+ }
+ return len;
+}