| /* Low level Unix child interface to ptrace, for GDB when running under Unix. |
| Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
| 1998, 1999, 2000, 2001, 2002 |
| Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program 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 2 of the License, or |
| (at your option) any later version. |
| |
| This program 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 this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| #include "defs.h" |
| #include "frame.h" |
| #include "inferior.h" |
| #include "target.h" |
| #include "gdb_string.h" |
| #include "regcache.h" |
| |
| #include "gdb_wait.h" |
| |
| #include "command.h" |
| |
| #ifdef USG |
| #include <sys/types.h> |
| #endif |
| |
| #include <sys/param.h> |
| #include "gdb_dirent.h" |
| #include <signal.h> |
| #include <sys/ioctl.h> |
| |
| #ifdef HAVE_PTRACE_H |
| #include <ptrace.h> |
| #else |
| #ifdef HAVE_SYS_PTRACE_H |
| #include <sys/ptrace.h> |
| #endif |
| #endif |
| |
| #if !defined (PT_READ_I) |
| #define PT_READ_I 1 /* Read word from text space */ |
| #endif |
| #if !defined (PT_READ_D) |
| #define PT_READ_D 2 /* Read word from data space */ |
| #endif |
| #if !defined (PT_READ_U) |
| #define PT_READ_U 3 /* Read word from kernel user struct */ |
| #endif |
| #if !defined (PT_WRITE_I) |
| #define PT_WRITE_I 4 /* Write word to text space */ |
| #endif |
| #if !defined (PT_WRITE_D) |
| #define PT_WRITE_D 5 /* Write word to data space */ |
| #endif |
| #if !defined (PT_WRITE_U) |
| #define PT_WRITE_U 6 /* Write word to kernel user struct */ |
| #endif |
| #if !defined (PT_CONTINUE) |
| #define PT_CONTINUE 7 /* Continue after signal */ |
| #endif |
| #if !defined (PT_STEP) |
| #define PT_STEP 9 /* Set flag for single stepping */ |
| #endif |
| #if !defined (PT_KILL) |
| #define PT_KILL 8 /* Send child a SIGKILL signal */ |
| #endif |
| |
| #ifndef PT_ATTACH |
| #define PT_ATTACH PTRACE_ATTACH |
| #endif |
| #ifndef PT_DETACH |
| #define PT_DETACH PTRACE_DETACH |
| #endif |
| |
| #include "gdbcore.h" |
| #ifndef NO_SYS_FILE |
| #include <sys/file.h> |
| #endif |
| #if 0 |
| /* Don't think this is used anymore. On the sequent (not sure whether it's |
| dynix or ptx or both), it is included unconditionally by sys/user.h and |
| not protected against multiple inclusion. */ |
| #include "gdb_stat.h" |
| #endif |
| |
| #if !defined (FETCH_INFERIOR_REGISTERS) |
| #include <sys/user.h> /* Probably need to poke the user structure */ |
| #if defined (KERNEL_U_ADDR_BSD) |
| #include <a.out.h> /* For struct nlist */ |
| #endif /* KERNEL_U_ADDR_BSD. */ |
| #endif /* !FETCH_INFERIOR_REGISTERS */ |
| |
| #if !defined (CHILD_XFER_MEMORY) |
| static void udot_info (char *, int); |
| #endif |
| |
| #if !defined (FETCH_INFERIOR_REGISTERS) |
| static void fetch_register (int); |
| static void store_register (int); |
| #endif |
| |
| void _initialize_kernel_u_addr (void); |
| void _initialize_infptrace (void); |
| |
| |
| /* 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 (int request, int pid, PTRACE_ARG3_TYPE addr, int data) |
| { |
| int pt_status = 0; |
| |
| #if 0 |
| int saved_errno; |
| |
| printf ("call_ptrace(request=%d, pid=%d, addr=0x%x, data=0x%x)", |
| request, pid, addr, data); |
| #endif |
| #if defined(PT_SETTRC) |
| /* If the parent can be told to attach to us, try to do it. */ |
| if (request == PT_SETTRC) |
| { |
| errno = 0; |
| #if !defined (FIVE_ARG_PTRACE) |
| pt_status = ptrace (PT_SETTRC, pid, addr, data); |
| #else |
| /* Deal with HPUX 8.0 braindamage. We never use the |
| calls which require the fifth argument. */ |
| pt_status = ptrace (PT_SETTRC, pid, addr, data, 0); |
| #endif |
| if (errno) |
| perror_with_name ("ptrace"); |
| #if 0 |
| printf (" = %d\n", pt_status); |
| #endif |
| if (pt_status < 0) |
| return pt_status; |
| else |
| return parent_attach_all (pid, addr, data); |
| } |
| #endif |
| |
| #if defined(PT_CONTIN1) |
| /* On HPUX, PT_CONTIN1 is a form of continue that preserves pending |
| signals. If it's available, use it. */ |
| if (request == PT_CONTINUE) |
| request = PT_CONTIN1; |
| #endif |
| |
| #if defined(PT_SINGLE1) |
| /* On HPUX, PT_SINGLE1 is a form of step that preserves pending |
| signals. If it's available, use it. */ |
| if (request == PT_STEP) |
| request = PT_SINGLE1; |
| #endif |
| |
| #if 0 |
| saved_errno = errno; |
| errno = 0; |
| #endif |
| #if !defined (FIVE_ARG_PTRACE) |
| pt_status = ptrace (request, pid, addr, data); |
| #else |
| /* Deal with HPUX 8.0 braindamage. We never use the |
| calls which require the fifth argument. */ |
| pt_status = ptrace (request, pid, addr, data, 0); |
| #endif |
| |
| #if 0 |
| if (errno) |
| printf (" [errno = %d]", errno); |
| |
| errno = saved_errno; |
| printf (" = 0x%x\n", pt_status); |
| #endif |
| return pt_status; |
| } |
| |
| |
| #if defined (DEBUG_PTRACE) || defined (FIVE_ARG_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 |
| |
| /* Wait for a process to finish, possibly running a target-specific |
| hook before returning. */ |
| |
| int |
| ptrace_wait (ptid_t ptid, int *status) |
| { |
| int wstate; |
| |
| wstate = wait (status); |
| target_post_wait (pid_to_ptid (wstate), *status); |
| return wstate; |
| } |
| |
| #ifndef KILL_INFERIOR |
| void |
| kill_inferior (void) |
| { |
| int status; |
| int pid = PIDGET (inferior_ptid); |
| |
| if (pid == 0) |
| return; |
| |
| /* 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 |
| 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. */ |
| ptrace (PT_KILL, pid, (PTRACE_ARG3_TYPE) 0, 0); |
| ptrace_wait (null_ptid, &status); |
| target_mourn_inferior (); |
| } |
| #endif /* KILL_INFERIOR */ |
| |
| #ifndef CHILD_RESUME |
| |
| /* Resume execution of the inferior process. |
| If STEP is nonzero, single-step it. |
| If SIGNAL is nonzero, give it that signal. */ |
| |
| void |
| child_resume (ptid_t ptid, int step, enum target_signal signal) |
| { |
| int pid = PIDGET (ptid); |
| |
| errno = 0; |
| |
| if (pid == -1) |
| /* Resume all threads. */ |
| /* I think this only gets used in the non-threaded case, where "resume |
| all threads" and "resume inferior_ptid" are the same. */ |
| pid = PIDGET (inferior_ptid); |
| |
| /* An address of (PTRACE_ARG3_TYPE)1 tells ptrace 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 this system does not support PT_STEP, a higher level function will |
| have called single_step() to transmute the step request into a |
| continue request (by setting breakpoints on all possible successor |
| instructions), so we don't have to worry about that here. */ |
| |
| if (step) |
| { |
| if (SOFTWARE_SINGLE_STEP_P ()) |
| internal_error (__FILE__, __LINE__, "failed internal consistency check"); /* Make sure this doesn't happen. */ |
| else |
| ptrace (PT_STEP, pid, (PTRACE_ARG3_TYPE) 1, |
| target_signal_to_host (signal)); |
| } |
| else |
| ptrace (PT_CONTINUE, pid, (PTRACE_ARG3_TYPE) 1, |
| target_signal_to_host (signal)); |
| |
| if (errno) |
| { |
| perror_with_name ("ptrace"); |
| } |
| } |
| #endif /* CHILD_RESUME */ |
| |
| |
| #ifdef ATTACH_DETACH |
| /* Start debugging the process whose number is PID. */ |
| int |
| attach (int pid) |
| { |
| errno = 0; |
| ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 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 (int signal) |
| { |
| errno = 0; |
| ptrace (PT_DETACH, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) 1, |
| signal); |
| if (errno) |
| print_sys_errmsg ("ptrace", errno); |
| attach_flag = 0; |
| } |
| #endif /* ATTACH_DETACH */ |
| |
| /* Default the type of the ptrace transfer to int. */ |
| #ifndef PTRACE_XFER_TYPE |
| #define PTRACE_XFER_TYPE int |
| #endif |
| |
| /* 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) && !defined (FETCH_INFERIOR_REGISTERS) |
| /* Get kernel_u_addr using BSD-style nlist(). */ |
| CORE_ADDR kernel_u_addr; |
| #endif /* KERNEL_U_ADDR_BSD. */ |
| |
| void |
| _initialize_kernel_u_addr (void) |
| { |
| #if defined (KERNEL_U_ADDR_BSD) && !defined (FETCH_INFERIOR_REGISTERS) |
| 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 |
| internal_error (__FILE__, __LINE__, |
| "Unable to get kernel u area address."); |
| #endif /* KERNEL_U_ADDR_BSD. */ |
| } |
| |
| #if !defined (FETCH_INFERIOR_REGISTERS) |
| |
| #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, PIDGET (inferior_ptid), \ |
| (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \ |
| - KERNEL_U_ADDR |
| #endif |
| |
| /* Fetch one register. */ |
| |
| static void |
| fetch_register (int regno) |
| { |
| /* This isn't really an address. But ptrace thinks of it as one. */ |
| CORE_ADDR regaddr; |
| char mess[128]; /* For messages */ |
| int i; |
| unsigned int offset; /* Offset of registers within the u area. */ |
| char buf[MAX_REGISTER_SIZE]; |
| int tid; |
| |
| if (CANNOT_FETCH_REGISTER (regno)) |
| { |
| memset (buf, '\0', DEPRECATED_REGISTER_RAW_SIZE (regno)); /* Supply zeroes */ |
| supply_register (regno, buf); |
| return; |
| } |
| |
| /* Overload thread id onto process id */ |
| if ((tid = TIDGET (inferior_ptid)) == 0) |
| tid = PIDGET (inferior_ptid); /* no thread id, just use process id */ |
| |
| offset = U_REGS_OFFSET; |
| |
| regaddr = register_addr (regno, offset); |
| for (i = 0; i < DEPRECATED_REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE)) |
| { |
| errno = 0; |
| *(PTRACE_XFER_TYPE *) & buf[i] = ptrace (PT_READ_U, tid, |
| (PTRACE_ARG3_TYPE) regaddr, 0); |
| regaddr += sizeof (PTRACE_XFER_TYPE); |
| if (errno != 0) |
| { |
| sprintf (mess, "reading register %s (#%d)", |
| REGISTER_NAME (regno), regno); |
| perror_with_name (mess); |
| } |
| } |
| supply_register (regno, buf); |
| } |
| |
| |
| /* Fetch register values from the inferior. |
| If REGNO is negative, do this for all registers. |
| Otherwise, REGNO specifies which register (so we can save time). */ |
| |
| void |
| fetch_inferior_registers (int regno) |
| { |
| if (regno >= 0) |
| { |
| fetch_register (regno); |
| } |
| else |
| { |
| for (regno = 0; regno < NUM_REGS; regno++) |
| { |
| fetch_register (regno); |
| } |
| } |
| } |
| |
| /* Store one register. */ |
| |
| static void |
| store_register (int regno) |
| { |
| /* This isn't really an address. But ptrace thinks of it as one. */ |
| CORE_ADDR regaddr; |
| char mess[128]; /* For messages */ |
| int i; |
| unsigned int offset; /* Offset of registers within the u area. */ |
| int tid; |
| char buf[MAX_REGISTER_SIZE]; |
| |
| if (CANNOT_STORE_REGISTER (regno)) |
| { |
| return; |
| } |
| |
| /* Overload thread id onto process id */ |
| if ((tid = TIDGET (inferior_ptid)) == 0) |
| tid = PIDGET (inferior_ptid); /* no thread id, just use process id */ |
| |
| offset = U_REGS_OFFSET; |
| |
| regaddr = register_addr (regno, offset); |
| |
| /* Put the contents of regno into a local buffer */ |
| regcache_collect (regno, buf); |
| |
| /* Store the local buffer into the inferior a chunk at the time. */ |
| for (i = 0; i < DEPRECATED_REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE)) |
| { |
| errno = 0; |
| ptrace (PT_WRITE_U, tid, (PTRACE_ARG3_TYPE) regaddr, |
| *(PTRACE_XFER_TYPE *) (buf + i)); |
| regaddr += sizeof (PTRACE_XFER_TYPE); |
| if (errno != 0) |
| { |
| sprintf (mess, "writing register %s (#%d)", |
| REGISTER_NAME (regno), regno); |
| perror_with_name (mess); |
| } |
| } |
| } |
| |
| /* Store our register values back into the inferior. |
| If REGNO is negative, do this for all registers. |
| Otherwise, REGNO specifies which register (so we can save time). */ |
| |
| void |
| store_inferior_registers (int regno) |
| { |
| if (regno >= 0) |
| { |
| store_register (regno); |
| } |
| else |
| { |
| for (regno = 0; regno < NUM_REGS; regno++) |
| { |
| store_register (regno); |
| } |
| } |
| } |
| #endif /* !defined (FETCH_INFERIOR_REGISTERS). */ |
| |
| |
| /* Set an upper limit on alloca. */ |
| #ifndef GDB_MAX_ALLOCA |
| #define GDB_MAX_ALLOCA 0x1000 |
| #endif |
| |
| #if !defined (CHILD_XFER_MEMORY) |
| /* 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 |
| child_ops doesn't allow memory operations to cross below us in the |
| target stack anyway. */ |
| |
| int |
| child_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_XFER_TYPE); |
| /* Round ending address up; get number of longwords that makes. */ |
| int count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) |
| / sizeof (PTRACE_XFER_TYPE)); |
| int alloc = count * sizeof (PTRACE_XFER_TYPE); |
| PTRACE_XFER_TYPE *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_XFER_TYPE *) alloca (alloc); |
| } |
| else |
| { |
| buffer = (PTRACE_XFER_TYPE *) 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_XFER_TYPE)) |
| { |
| /* Need part of initial word -- fetch it. */ |
| buffer[0] = ptrace (PT_READ_I, PIDGET (inferior_ptid), |
| (PTRACE_ARG3_TYPE) addr, 0); |
| } |
| |
| if (count > 1) /* FIXME, avoid if even boundary. */ |
| { |
| buffer[count - 1] = |
| ptrace (PT_READ_I, PIDGET (inferior_ptid), |
| ((PTRACE_ARG3_TYPE) |
| (addr + (count - 1) * sizeof (PTRACE_XFER_TYPE))), 0); |
| } |
| |
| /* Copy data to be written over corresponding part of buffer. */ |
| memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), |
| myaddr, len); |
| |
| /* Write the entire buffer. */ |
| for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) |
| { |
| errno = 0; |
| ptrace (PT_WRITE_D, PIDGET (inferior_ptid), |
| (PTRACE_ARG3_TYPE) 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_ARG3_TYPE) addr, buffer[i]); |
| } |
| if (errno) |
| return 0; |
| } |
| #ifdef CLEAR_INSN_CACHE |
| CLEAR_INSN_CACHE (); |
| #endif |
| } |
| else |
| { |
| /* Read all the longwords. */ |
| for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) |
| { |
| errno = 0; |
| buffer[i] = ptrace (PT_READ_I, PIDGET (inferior_ptid), |
| (PTRACE_ARG3_TYPE) addr, 0); |
| if (errno) |
| return 0; |
| QUIT; |
| } |
| |
| /* Copy appropriate bytes out of the buffer. */ |
| memcpy (myaddr, |
| (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), |
| len); |
| } |
| |
| if (old_chain != NULL) |
| do_cleanups (old_chain); |
| return len; |
| } |
| |
| |
| static void |
| udot_info (char *dummy1, int dummy2) |
| { |
| #if defined (KERNEL_U_SIZE) |
| long udot_off; /* Offset into user struct */ |
| int udot_val; /* Value from user struct at udot_off */ |
| char mess[128]; /* For messages */ |
| #endif |
| |
| if (!target_has_execution) |
| { |
| error ("The program is not being run."); |
| } |
| |
| #if !defined (KERNEL_U_SIZE) |
| |
| /* Adding support for this command is easy. Typically you just add a |
| routine, called "kernel_u_size" that returns the size of the user |
| struct, to the appropriate *-nat.c file and then add to the native |
| config file "#define KERNEL_U_SIZE kernel_u_size()" */ |
| error ("Don't know how large ``struct user'' is in this version of gdb."); |
| |
| #else |
| |
| for (udot_off = 0; udot_off < KERNEL_U_SIZE; udot_off += sizeof (udot_val)) |
| { |
| if ((udot_off % 24) == 0) |
| { |
| if (udot_off > 0) |
| { |
| printf_filtered ("\n"); |
| } |
| printf_filtered ("%s:", paddr (udot_off)); |
| } |
| udot_val = ptrace (PT_READ_U, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) udot_off, 0); |
| if (errno != 0) |
| { |
| sprintf (mess, "\nreading user struct at offset 0x%s", |
| paddr_nz (udot_off)); |
| perror_with_name (mess); |
| } |
| /* Avoid using nonportable (?) "*" in print specs */ |
| printf_filtered (sizeof (int) == 4 ? " 0x%08x" : " 0x%16x", udot_val); |
| } |
| printf_filtered ("\n"); |
| |
| #endif |
| } |
| #endif /* !defined (CHILD_XFER_MEMORY). */ |
| |
| |
| void |
| _initialize_infptrace (void) |
| { |
| #if !defined (CHILD_XFER_MEMORY) |
| add_info ("udot", udot_info, |
| "Print contents of kernel ``struct user'' for current child."); |
| #endif |
| } |