-/* Low level Unix child interface to ptrace, for GDB when running under Unix.
+/* Low-level child interface to ptrace.
Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
- 1998, 1999, 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
+ 1998, 1999, 2000, 2001, 2002, 2004, 2005
+ Free Software Foundation, Inc.
This file is part of GDB.
Boston, MA 02111-1307, USA. */
#include "defs.h"
-#include "observer.h"
-#include "gdb_ptrace.h"
-#include "inflow.h"
-#include "inferior.h"
-#include "regcache.h"
#include "command.h"
+#include "inferior.h"
+#include "inflow.h"
#include "gdbcore.h"
-#include "inf-child.h"
-#include "gdbcmd.h"
-#include "gdb_string.h"
+#include "observer.h"
+#include "regcache.h"
-#include <sys/wait.h>
+#include "gdb_assert.h"
+#include "gdb_string.h"
+#include "gdb_ptrace.h"
+#include "gdb_wait.h"
#include <signal.h>
-/* HACK: Save the ptrace ops returned by ptrace_target. */
+#include "inf-child.h"
+
+/* HACK: Save the ptrace ops returned by inf_ptrace_target. */
static struct target_ops *ptrace_ops_hack;
static void
/* This once used to call "kill" to kill the inferior just in case
the inferior was still running. As others have noted in the past
(kingdon) there shouldn't be any way to get here if the inferior
- is still running -- else there's a major problem elsewere in gdb
+ is still running -- else there's a major problem elsewere in GDB
and it needs to be fixed.
- The kill call causes problems under hpux10, so it's been removed;
- if this causes problems we'll deal with them as they arise. */
+ The kill call causes problems under HP-UX 10, so it's been
+ removed; if this causes problems we'll deal with them as they
+ arise. */
ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3) 0, 0);
wait (&status);
target_mourn_inferior ();
perror_with_name ("ptrace");
}
-/* Set an upper limit on alloca. */
-#define GDB_MAX_ALLOCA 0x1000
-
-/* 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. TARGET is ignored.
-
- Returns the length copied, which is either the LEN argument or
- zero. This xfer function does not do partial moves, since
- ptrace_ops_hack doesn't allow memory operations to cross below us in the
- target stack anyway. */
-
-int
-inf_ptrace_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
- struct mem_attrib *attrib, struct target_ops *target)
-{
- int i;
- /* Round starting address down to longword boundary. */
- CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_TYPE_RET);
- /* Round ending address up; get number of longwords that makes. */
- int count = ((((memaddr + len) - addr) + sizeof (PTRACE_TYPE_RET) - 1)
- / sizeof (PTRACE_TYPE_RET));
- int alloc = count * sizeof (PTRACE_TYPE_RET);
- PTRACE_TYPE_RET *buffer;
- struct cleanup *old_chain = NULL;
-
-#ifdef PT_IO
- /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO request
- that promises to be much more efficient in reading and writing
- data in the traced process's address space. */
-
- {
- struct ptrace_io_desc piod;
-
- /* NOTE: We assume that there are no distinct address spaces for
- instruction and data. */
- piod.piod_op = write ? PIOD_WRITE_D : PIOD_READ_D;
- piod.piod_offs = (void *) memaddr;
- piod.piod_addr = myaddr;
- piod.piod_len = len;
-
- if (ptrace (PT_IO, PIDGET (inferior_ptid), (caddr_t) &piod, 0) == -1)
- {
- /* If the PT_IO request is somehow not supported, fallback on
- using PT_WRITE_D/PT_READ_D. Otherwise we will return zero
- to indicate failure. */
- if (errno != EINVAL)
- return 0;
- }
- else
- {
- /* Return the actual number of bytes read or written. */
- return piod.piod_len;
- }
- }
-#endif
-
- /* Allocate buffer of that many longwords. */
- if (len < GDB_MAX_ALLOCA)
- {
- buffer = (PTRACE_TYPE_RET *) alloca (alloc);
- }
- else
- {
- buffer = (PTRACE_TYPE_RET *) xmalloc (alloc);
- old_chain = make_cleanup (xfree, buffer);
- }
-
- if (write)
- {
- /* Fill start and end extra bytes of buffer with existing memory
- data. */
- if (addr != memaddr || len < (int) sizeof (PTRACE_TYPE_RET))
- {
- /* Need part of initial word -- fetch it. */
- buffer[0] = ptrace (PT_READ_I, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, 0);
- }
-
- if (count > 1) /* FIXME, avoid if even boundary. */
- {
- buffer[count - 1] =
- ptrace (PT_READ_I, PIDGET (inferior_ptid),
- ((PTRACE_TYPE_ARG3)
- (addr + (count - 1) * sizeof (PTRACE_TYPE_RET))), 0);
- }
-
- /* Copy data to be written over corresponding part of buffer. */
- memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
- myaddr, len);
-
- /* Write the entire buffer. */
- for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
- {
- errno = 0;
- ptrace (PT_WRITE_D, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) 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, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, buffer[i]);
- }
- if (errno)
- return 0;
- }
- }
- else
- {
- /* Read all the longwords. */
- for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
- {
- errno = 0;
- buffer[i] = ptrace (PT_READ_I, PIDGET (inferior_ptid),
- (PTRACE_TYPE_ARG3) addr, 0);
- if (errno)
- return 0;
- QUIT;
- }
-
- /* Copy appropriate bytes out of the buffer. */
- memcpy (myaddr,
- (char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
- len);
- }
-
- if (old_chain != NULL)
- do_cleanups (old_chain);
- return len;
-}
-
/* Wait for child to do something. Return pid of child, or -1 in case
of error; store status through argument pointer OURSTATUS. */
set_sigio_trap ();
pid = wait (&status);
- target_post_wait (pid_to_ptid (pid), status);
save_errno = errno;
return pid_to_ptid (-1);
}
- /* Did it exit?
- */
+ /* Did it exit? */
if (target_has_exited (pid, status, &exit_status))
{
/* ??rehrauer: For now, ignore this. */
return pid_to_ptid (pid);
}
}
- while (pid != PIDGET (inferior_ptid)); /* Some other child died or stopped */
+ while (pid != PIDGET (inferior_ptid)); /* Some other child died or
+ stopped. */
store_waitstatus (ourstatus, status);
return pid_to_ptid (pid);
}
-void
-inf_ptrace_post_wait (ptid_t ptid, int wait_status)
-{
- /* This version of Unix doesn't require a meaningful "post wait"
- operation.
- */
-}
-
/* Check to see if the given thread is alive.
FIXME: Is kill() ever the right way to do this? I doubt it, but
dummy = args;
pid = strtol (args, &dummy, 0);
- /* Some targets don't set errno on errors, grrr! */
+ /* Some targets don't set errno on errors, grrr! */
if (pid == 0 && args == dummy)
error ("Illegal process-id: %s\n", args);
- if (pid == getpid ()) /* Trying to masturbate? */
+ if (pid == getpid ()) /* Trying to masturbate? */
error ("I refuse to debug myself!");
if (from_tty)
inferior_ptid = pid_to_ptid (pid);
push_target (ptrace_ops_hack);
+
+ /* Do this first, before anything has had a chance to query the
+ inferior's symbol table or similar. */
+ observer_notify_inferior_created (¤t_target, from_tty);
}
static void
static void
inf_ptrace_me (void)
{
- /* "Trace me, Dr. Memory!" */
+ /* "Trace me, Dr. Memory!" */
ptrace (0, 0, (PTRACE_TYPE_ARG3) 0, 0);
}
/* On some targets, there must be some explicit synchronization
between the parent and child processes after the debugger
forks, and before the child execs the debuggee program. This
- call basically gives permission for the child to exec.
- */
+ call basically gives permission for the child to exec. */
target_acknowledge_created_inferior (pid);
- /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h,
- * and will be 1 or 2 depending on whether we're starting
- * without or with a shell.
- */
+ /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will
+ be 1 or 2 depending on whether we're starting without or with a
+ shell. */
startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
/* On some targets, there must be some explicit actions taken after
- the inferior has been started up.
- */
+ the inferior has been started up. */
target_post_startup_inferior (pid_to_ptid (pid));
}
NULL, NULL);
/* We are at the first instruction we care about. */
observer_notify_inferior_created (¤t_target, from_tty);
- /* Pedal to the metal... */
+ /* Pedal to the metal... */
proceed ((CORE_ADDR) -1, TARGET_SIGNAL_0, 0);
}
static void
inf_ptrace_post_startup_inferior (ptid_t ptid)
{
- /* This version of Unix doesn't require a meaningful "post startup inferior"
- operation by a debugger.
- */
+ /* This version of Unix doesn't require a meaningful "post startup
+ inferior" operation by a debugger. */
}
static void
inf_ptrace_acknowledge_created_inferior (int pid)
{
- /* This version of Unix doesn't require a meaningful "acknowledge created inferior"
- operation by a debugger.
- */
+ /* This version of Unix doesn't require a meaningful "acknowledge
+ created inferior" operation by a debugger. */
}
static int
static int
inf_ptrace_reported_exec_events_per_exec_call (void)
{
- /* This version of Unix doesn't support notification of exec events.
- */
+ /* This version of Unix doesn't support notification of exec events. */
return 1;
}
return 1;
}
- /* ?? Do we really need to consult the event state, too? Assume the
- wait_state alone suffices.
- */
+ /* ??? Do we really need to consult the event state, too?
+ Assume the wait_state alone suffices. */
return 0;
}
/* Send a SIGINT to the process group. This acts just like the user
typed a ^C on the controlling terminal.
- XXX - This may not be correct for all systems. Some may want to
- use killpg() instead of kill (-pgrp). */
+ FIXME: This may not be correct for all systems. Some may want to
+ use killpg() instead of kill (-pgrp). */
static void
inf_ptrace_stop (void)
switch (object)
{
case TARGET_OBJECT_MEMORY:
- if (readbuf)
- return inf_ptrace_xfer_memory (offset, readbuf, len, 0 /*write */ ,
- NULL, ops);
- if (writebuf)
- return inf_ptrace_xfer_memory (offset, readbuf, len, 1 /*write */ ,
- NULL, ops);
- return -1;
+#ifdef PT_IO
+ /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO
+ request that promises to be much more efficient in reading
+ and writing data in the traced process's address space. */
+ {
+ struct ptrace_io_desc piod;
+
+ /* NOTE: We assume that there are no distinct address spaces
+ for instruction and data. */
+ piod.piod_op = writebuf ? PIOD_WRITE_D : PIOD_READ_D;
+ piod.piod_addr = writebuf ? (void *) writebuf : readbuf;
+ piod.piod_offs = (void *) (long) offset;
+ piod.piod_len = len;
+
+ errno = 0;
+ if (ptrace (PT_IO, PIDGET (inferior_ptid), (caddr_t) &piod, 0) == 0)
+ /* Return the actual number of bytes read or written. */
+ return piod.piod_len;
+ /* If the PT_IO request is somehow not supported, fallback on
+ using PT_WRITE_D/PT_READ_D. Otherwise we will return zero
+ to indicate failure. */
+ if (errno != EINVAL)
+ return 0;
+ }
+#endif
+ {
+ union
+ {
+ PTRACE_TYPE_RET word;
+ unsigned char byte[sizeof (PTRACE_TYPE_RET)];
+ } buffer;
+ ULONGEST rounded_offset;
+ LONGEST partial_len;
+
+ /* Round the start offset down to the next long word
+ boundary. */
+ rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET);
+
+ /* Since ptrace will transfer a single word starting at that
+ rounded_offset the partial_len needs to be adjusted down to
+ that (remember this function only does a single transfer).
+ Should the required length be even less, adjust it down
+ again. */
+ partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset;
+ if (partial_len > len)
+ partial_len = len;
+
+ if (writebuf)
+ {
+ /* If OFFSET:PARTIAL_LEN is smaller than
+ ROUNDED_OFFSET:WORDSIZE then a read/modify write will
+ be needed. Read in the entire word. */
+ if (rounded_offset < offset
+ || (offset + partial_len
+ < rounded_offset + sizeof (PTRACE_TYPE_RET)))
+ /* Need part of initial word -- fetch it. */
+ buffer.word = ptrace (PT_READ_I, PIDGET (inferior_ptid),
+ (PTRACE_TYPE_ARG3) (long) rounded_offset,
+ 0);
+
+ /* Copy data to be written over corresponding part of
+ buffer. */
+ memcpy (buffer.byte + (offset - rounded_offset),
+ writebuf, partial_len);
+
+ errno = 0;
+ ptrace (PT_WRITE_D, PIDGET (inferior_ptid),
+ (PTRACE_TYPE_ARG3) (long) rounded_offset,
+ buffer.word);
+ if (errno)
+ {
+ /* Using the appropriate one (I or D) is necessary for
+ Gould NP1, at least. */
+ errno = 0;
+ ptrace (PT_WRITE_I, PIDGET (inferior_ptid),
+ (PTRACE_TYPE_ARG3) (long) rounded_offset,
+ buffer.word);
+ if (errno)
+ return 0;
+ }
+ }
+ if (readbuf)
+ {
+ errno = 0;
+ buffer.word = ptrace (PT_READ_I, PIDGET (inferior_ptid),
+ (PTRACE_TYPE_ARG3) (long) rounded_offset, 0);
+ if (errno)
+ return 0;
+ /* Copy appropriate bytes out of the buffer. */
+ memcpy (readbuf, buffer.byte + (offset - rounded_offset),
+ partial_len);
+ }
+ return partial_len;
+ }
case TARGET_OBJECT_UNWIND_TABLE:
return -1;
return normal_pid_to_str (ptid);
}
+/* Create a prototype ptrace target. The client can override it with
+ local methods. */
+
struct target_ops *
inf_ptrace_target (void)
{
struct target_ops *t = inf_child_target ();
+
t->to_open = inf_ptrace_open;
t->to_attach = inf_ptrace_attach;
t->to_post_attach = inf_ptrace_post_attach;
t->to_detach = inf_ptrace_detach;
t->to_resume = inf_ptrace_resume;
t->to_wait = inf_ptrace_wait;
- t->to_post_wait = inf_ptrace_post_wait;
t->to_prepare_to_store = inf_ptrace_prepare_to_store;
- t->to_xfer_memory = inf_ptrace_xfer_memory;
t->to_xfer_partial = inf_ptrace_xfer_partial;
t->to_files_info = inf_ptrace_files_info;
t->to_kill = inf_ptrace_kill_inferior;
t->to_has_execution = 1;
t->to_magic = OPS_MAGIC;
ptrace_ops_hack = t;
+
+ return t;
+}
+\f
+
+/* Pointer to a function that returns the oggset within the user area
+ where a particular register is stored. */
+static CORE_ADDR (*inf_ptrace_register_u_offset)(int);
+
+/* Fetch register REGNUM from the inferior. */
+
+static void
+inf_ptrace_fetch_register (int regnum)
+{
+ CORE_ADDR addr;
+ size_t size;
+ PTRACE_TYPE_RET *buf;
+ int pid, i;
+
+ /* Cater for systems like GNU/Linux, that implement threads as
+ seperate processes. */
+ pid = ptid_get_lwp (inferior_ptid);
+ if (pid == 0)
+ pid = ptid_get_pid (inferior_ptid);
+
+ /* This isn't really an address, but ptrace thinks of it as one. */
+ addr = inf_ptrace_register_u_offset (regnum);
+ size = register_size (current_gdbarch, regnum);
+
+ gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
+ buf = alloca (size);
+
+ /* Read the register contents from the inferior a chuck at the time. */
+ for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++)
+ {
+ errno = 0;
+ buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3) addr, 0);
+ if (errno != 0)
+ error ("Couldn't read register %s (#%d): %s.", REGISTER_NAME (regnum),
+ regnum, safe_strerror (errno));
+
+ addr += sizeof (PTRACE_TYPE_RET);
+ }
+ regcache_raw_supply (current_regcache, regnum, buf);
+}
+
+/* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
+ for all registers. */
+
+static void
+inf_ptrace_fetch_registers (int regnum)
+{
+ if (regnum == -1)
+ for (regnum = 0; regnum < NUM_REGS; regnum++)
+ inf_ptrace_fetch_register (regnum);
+ else
+ inf_ptrace_fetch_register (regnum);
+}
+
+/* Store register REGNUM into the inferior. */
+
+static void
+inf_ptrace_store_register (int regnum)
+{
+ CORE_ADDR addr;
+ size_t size;
+ PTRACE_TYPE_RET *buf;
+ int pid, i;
+
+ /* Cater for systems like GNU/Linux, that implement threads as
+ seperate processes. */
+ pid = ptid_get_lwp (inferior_ptid);
+ if (pid == 0)
+ pid = ptid_get_pid (inferior_ptid);
+
+ /* This isn't really an address, but ptrace thinks of it as one. */
+ addr = inf_ptrace_register_u_offset (regnum);
+ size = register_size (current_gdbarch, regnum);
+
+ gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
+ buf = alloca (size);
+
+ /* Write the register contents into the inferior a chunk at the time. */
+ regcache_raw_collect (current_regcache, regnum, buf);
+ for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++)
+ {
+ errno = 0;
+ ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3) addr, buf[i]);
+ if (errno != 0)
+ error ("Couldn't write register %s (#%d): %s.", REGISTER_NAME (regnum),
+ regnum, safe_strerror (errno));
+
+ addr += sizeof (PTRACE_TYPE_RET);
+ }
+}
+
+/* Store register REGNUM back into the inferior. If REGNUM is -1, do
+ this for all registers. */
+
+void
+inf_ptrace_store_registers (int regnum)
+{
+ if (regnum == -1)
+ for (regnum = 0; regnum < NUM_REGS; regnum++)
+ inf_ptrace_store_register (regnum);
+ else
+ inf_ptrace_store_register (regnum);
+}
+
+/* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be
+ a function returning the offset within the user area where a
+ particular register is stored. */
+
+struct target_ops *
+inf_ptrace_trad_target (CORE_ADDR (*register_u_offset)(int))
+{
+ struct target_ops *t = inf_ptrace_target();
+
+ gdb_assert (register_u_offset);
+ inf_ptrace_register_u_offset = register_u_offset;
+ t->to_fetch_registers = inf_ptrace_fetch_registers;
+ t->to_store_registers = inf_ptrace_store_registers;
+
return t;
}
projects / deliverable / binutils-gdb.git / blobdiff