From 0d14c7df689bea7cc7d8cfb953a51ada7c700d1d Mon Sep 17 00:00:00 2001 From: Fred Fish Date: Wed, 10 Jan 1996 18:40:24 +0000 Subject: From Wilfried Moser : * gdbserver/low-linux.c: New file. * remote.c (remote_read_bytes): Fix aborts on larger packets. * config/i386/linux.mh (GDBSERVER_DEPFILES, GDBSERVER_LIBS): Define. * stabsread.c (define_symbol): If register value is too large, tell what it is and what max is. --- gdb/gdbserver/low-linux.c | 421 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 421 insertions(+) create mode 100644 gdb/gdbserver/low-linux.c (limited to 'gdb/gdbserver/low-linux.c') diff --git a/gdb/gdbserver/low-linux.c b/gdb/gdbserver/low-linux.c new file mode 100644 index 0000000..046a9be --- /dev/null +++ b/gdb/gdbserver/low-linux.c @@ -0,0 +1,421 @@ +/* Low level interface to ptrace, for the remote server for GDB. + Copyright (C) 1995, 1996 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 +#include "frame.h" +#include "inferior.h" + +#include +#include +#include +#include +#include +#include +#if 0 +#include +#endif +#include + +/***************Begin MY defs*********************/ +int quit_flag = 0; +char registers[REGISTER_BYTES]; + +/* Index within `registers' of the first byte of the space for + register N. */ + + +char buf2[MAX_REGISTER_RAW_SIZE]; +/***************End MY defs*********************/ + +#include +#if 0 +#include +#endif + +extern char **environ; +extern int errno; +extern int inferior_pid; +void quit (), perror_with_name (); +int query (); + +/* Start an inferior process and returns its pid. + ALLARGS is a vector of program-name and args. + ENV is the environment vector to pass. */ + +int +create_inferior (program, allargs) + char *program; + char **allargs; +{ + int pid; + + pid = fork (); + if (pid < 0) + perror_with_name ("fork"); + + if (pid == 0) + { + ptrace (PTRACE_TRACEME, 0, 0, 0); + + execv (program, allargs); + + fprintf (stderr, "Cannot exec %s: %s.\n", program, + errno < sys_nerr ? sys_errlist[errno] : "unknown error"); + fflush (stderr); + _exit (0177); + } + + return pid; +} + +/* Kill the inferior process. Make us have no inferior. */ + +void +kill_inferior () +{ + if (inferior_pid == 0) + return; + ptrace (PTRACE_KILL, inferior_pid, 0, 0); + wait (0); + /*************inferior_died ();****VK**************/ +} + +/* Return nonzero if the given thread is still alive. */ +int +mythread_alive (pid) + int pid; +{ + return 1; +} + +/* Wait for process, returns status */ + +unsigned char +mywait (status) + char *status; +{ + int pid; + union wait w; + + pid = wait (&w); + if (pid != inferior_pid) + perror_with_name ("wait"); + + if (WIFEXITED (w)) + { + fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w)); + *status = 'W'; + return ((unsigned char) WEXITSTATUS (w)); + } + else if (!WIFSTOPPED (w)) + { + fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w)); + *status = 'X'; + return ((unsigned char) WTERMSIG (w)); + } + + fetch_inferior_registers (0); + + *status = 'T'; + return ((unsigned char) WSTOPSIG (w)); +} + +/* Resume execution of the inferior process. + If STEP is nonzero, single-step it. + If SIGNAL is nonzero, give it that signal. */ + +void +myresume (step, signal) + int step; + int signal; +{ + errno = 0; + ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, inferior_pid, 1, signal); + if (errno) + perror_with_name ("ptrace"); +} + + +#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, \ + (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \ + - KERNEL_U_ADDR +#endif + +/* this table must line up with REGISTER_NAMES in tm-i386v.h */ +/* symbols like 'EAX' come from */ +static int regmap[] = +{ + EAX, ECX, EDX, EBX, + UESP, EBP, ESI, EDI, + EIP, EFL, CS, SS, + DS, ES, FS, GS, +}; + +int +i386_register_u_addr (blockend, regnum) + int blockend; + int regnum; +{ +#if 0 + /* this will be needed if fp registers are reinstated */ + /* for now, you can look at them with 'info float' + * sys5 wont let you change them with ptrace anyway + */ + if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM) + { + int ubase, fpstate; + struct user u; + ubase = blockend + 4 * (SS + 1) - KSTKSZ; + fpstate = ubase + ((char *)&u.u_fpstate - (char *)&u); + return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM)); + } + else +#endif + return (blockend + 4 * regmap[regnum]); + +} + +unsigned int +register_addr (regno, blockend) + int regno; + int blockend; +{ + int addr; + + if (regno < 0 || regno >= ARCH_NUM_REGS) + error ("Invalid register number %d.", regno); + + REGISTER_U_ADDR (addr, blockend, regno); + + return addr; +} + +/* 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; + + offset = U_REGS_OFFSET; + + regaddr = register_addr (regno, offset); + for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int)) + { + errno = 0; + *(int *) ®isters[ regno * 4 + i] = ptrace (PTRACE_PEEKUSR, inferior_pid, + (PTRACE_ARG3_TYPE) regaddr, 0); + regaddr += sizeof (int); + if (errno != 0) + { + /* Warning, not error, in case we are attached; sometimes the + kernel doesn't let us at the registers. */ + char *err = strerror (errno); + char *msg = alloca (strlen (err) + 128); + sprintf (msg, "reading register %d: %s", regno, err); + error (msg); + goto error_exit; + } + } + error_exit:; +} + +/* Fetch all registers, or just one, from the child process. */ + +void +fetch_inferior_registers (regno) + int regno; +{ + if (regno == -1 || regno == 0) + for (regno = 0; regno < NUM_REGS-NUM_FREGS; regno++) + fetch_register (regno); + else + fetch_register (regno); +} + +/* 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). */ + +void +store_inferior_registers (regno) + int regno; +{ + register unsigned int regaddr; + char buf[80]; + extern char registers[]; + register int i; + unsigned int offset = U_REGS_OFFSET; + int scratch; + + if (regno >= 0) + { +#if 0 + if (CANNOT_STORE_REGISTER (regno)) + return; +#endif + regaddr = register_addr (regno, offset); + errno = 0; +#if 0 + if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM) + { + scratch = *(int *) ®isters[REGISTER_BYTE (regno)] | 0x3; + ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, + scratch, 0); + if (errno != 0) + { + /* Error, even if attached. Failing to write these two + registers is pretty serious. */ + sprintf (buf, "writing register number %d", regno); + perror_with_name (buf); + } + } + else +#endif + for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int)) + { + errno = 0; + ptrace (PTRACE_POKEUSR, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, + *(int *) ®isters[REGISTER_BYTE (regno) + i]); + if (errno != 0) + { + /* Warning, not error, in case we are attached; sometimes the + kernel doesn't let us at the registers. */ + char *err = strerror (errno); + char *msg = alloca (strlen (err) + 128); + sprintf (msg, "writing register %d: %s", + regno, err); + error (msg); + return; + } + regaddr += sizeof(int); + } + } + else + for (regno = 0; regno < NUM_REGS-NUM_FREGS; regno++) + store_inferior_registers (regno); +} + +/* 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 from inferior's memory starting at MEMADDR + to debugger memory starting at MYADDR. */ + +read_inferior_memory (memaddr, myaddr, len) + CORE_ADDR memaddr; + char *myaddr; + int len; +{ + 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)); + + /* Read all the longwords */ + for (i = 0; i < count; i++, addr += sizeof (int)) + { + buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, addr, 0); + } + + /* Copy appropriate bytes out of the buffer. */ + memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len); +} + +/* Copy LEN bytes of data from debugger memory at MYADDR + to inferior's memory at MEMADDR. + On failure (cannot write the inferior) + returns the value of errno. */ + +int +write_inferior_memory (memaddr, myaddr, len) + CORE_ADDR memaddr; + char *myaddr; + int len; +{ + 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)); + extern int errno; + + /* Fill start and end extra bytes of buffer with existing memory data. */ + + buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid, addr, 0); + + if (count > 1) + { + buffer[count - 1] + = ptrace (PTRACE_PEEKTEXT, inferior_pid, + addr + (count - 1) * sizeof (int), 0); + } + + /* Copy data to be written over corresponding part of buffer */ + + memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len); + + /* Write the entire buffer. */ + + for (i = 0; i < count; i++, addr += sizeof (int)) + { + errno = 0; + ptrace (PTRACE_POKETEXT, inferior_pid, addr, buffer[i]); + if (errno) + return errno; + } + + return 0; +} + +void +initialize () +{ + inferior_pid = 0; +} + +int +have_inferior_p () +{ + return inferior_pid != 0; +} -- cgit v1.1