| /* Low level Pyramid interface to ptrace, for GDB when running under Unix. |
| Copyright (C) 1988, 1989, 1991 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 <sys/param.h> |
| #include <sys/dir.h> |
| #include <signal.h> |
| #include <sys/ioctl.h> |
| /* #include <fcntl.h> Can we live without this? */ |
| |
| #include "gdbcore.h" |
| #include <sys/user.h> /* After a.out.h */ |
| #include <sys/file.h> |
| #include "gdb_stat.h" |
| |
| |
| void |
| fetch_inferior_registers (regno) |
| int regno; |
| { |
| register int datum; |
| register unsigned int regaddr; |
| int reg_buf[NUM_REGS+1]; |
| struct user u; |
| register int skipped_frames = 0; |
| |
| registers_fetched (); |
| |
| for (regno = 0; regno < 64; regno++) { |
| reg_buf[regno] = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) regno, 0); |
| |
| #if defined(PYRAMID_CONTROL_FRAME_DEBUGGING) |
| printf_unfiltered ("Fetching register %s, got %0x\n", |
| REGISTER_NAME (regno), |
| reg_buf[regno]); |
| #endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ |
| |
| if (reg_buf[regno] == -1 && errno == EIO) { |
| printf_unfiltered("fetch_interior_registers: fetching register %s\n", |
| REGISTER_NAME (regno)); |
| errno = 0; |
| } |
| supply_register (regno, reg_buf+regno); |
| } |
| /* that leaves regs 64, 65, and 66 */ |
| datum = ptrace (3, inferior_pid, |
| (PTRACE_ARG3_TYPE) (((char *)&u.u_pcb.pcb_csp) - |
| ((char *)&u)), 0); |
| |
| |
| |
| /* FIXME: Find the Current Frame Pointer (CFP). CFP is a global |
| register (ie, NOT windowed), that gets saved in a frame iff |
| the code for that frame has a prologue (ie, "adsf N"). If |
| there is a prologue, the adsf insn saves the old cfp in |
| pr13, cfp is set to sp, and N bytes of locals are allocated |
| (sp is decremented by n). |
| This makes finding CFP hard. I guess the right way to do it |
| is: |
| - If this is the innermost frame, believe ptrace() or |
| the core area. |
| - Otherwise: |
| Find the first insn of the current frame. |
| - find the saved pc; |
| - find the call insn that saved it; |
| - figure out where the call is to; |
| - if the first insn is an adsf, we got a frame |
| pointer. */ |
| |
| |
| /* Normal processors have separate stack pointers for user and |
| kernel mode. Getting the last user mode frame on such |
| machines is easy: the kernel context of the ptrace()'d |
| process is on the kernel stack, and the USP points to what |
| we want. But Pyramids only have a single cfp for both user and |
| kernel mode. And processes being ptrace()'d have some |
| kernel-context control frames on their stack. |
| To avoid tracing back into the kernel context of an inferior, |
| we skip 0 or more contiguous control frames where the pc is |
| in the kernel. */ |
| |
| while (1) { |
| register int inferior_saved_pc; |
| inferior_saved_pc = ptrace (1, inferior_pid, |
| (PTRACE_ARG3_TYPE) (datum+((32+15)*4)), 0); |
| if (inferior_saved_pc > 0) break; |
| #if defined(PYRAMID_CONTROL_FRAME_DEBUGGING) |
| printf_unfiltered("skipping kernel frame %08x, pc=%08x\n", datum, |
| inferior_saved_pc); |
| #endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ |
| skipped_frames++; |
| datum -= CONTROL_STACK_FRAME_SIZE; |
| } |
| |
| reg_buf[CSP_REGNUM] = datum; |
| supply_register(CSP_REGNUM, reg_buf+CSP_REGNUM); |
| #ifdef PYRAMID_CONTROL_FRAME_DEBUGGING |
| if (skipped_frames) { |
| fprintf_unfiltered (gdb_stderr, |
| "skipped %d frames from %x to %x; cfp was %x, now %x\n", |
| skipped_frames, reg_buf[CSP_REGNUM]); |
| } |
| #endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ |
| } |
| |
| /* 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]; |
| |
| if (regno >= 0) |
| { |
| if ((0 <= regno) && (regno < 64)) { |
| /*regaddr = register_addr (regno, offset);*/ |
| regaddr = regno; |
| errno = 0; |
| ptrace (6, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, |
| read_register (regno)); |
| if (errno != 0) |
| { |
| sprintf (buf, "writing register number %d", regno); |
| perror_with_name (buf); |
| } |
| } |
| } |
| else |
| { |
| for (regno = 0; regno < NUM_REGS; regno++) |
| { |
| /*regaddr = register_addr (regno, offset);*/ |
| regaddr = regno; |
| errno = 0; |
| ptrace (6, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, |
| read_register (regno)); |
| if (errno != 0) |
| { |
| sprintf (buf, "writing all regs, number %d", regno); |
| perror_with_name (buf); |
| } |
| } |
| } |
| |
| /*** Extensions to core and dump files, for GDB. */ |
| |
| extern unsigned int last_frame_offset; |
| |
| #ifdef PYRAMID_CORE |
| |
| /* Can't make definitions here static, since corefile.c needs them |
| to do bounds checking on the core-file areas. O well. */ |
| |
| /* have two stacks: one for data, one for register windows. */ |
| extern CORE_ADDR reg_stack_start; |
| extern CORE_ADDR reg_stack_end; |
| |
| /* need this so we can find the global registers: they never get saved. */ |
| CORE_ADDR global_reg_offset; |
| static CORE_ADDR last_frame_address; |
| CORE_ADDR last_frame_offset; |
| |
| |
| /* Address in core file of start of register window stack area. |
| Don't know if is this any of meaningful, useful or necessary. */ |
| extern int reg_stack_offset; |
| |
| #endif /* PYRAMID_CORE */ |
| |
| |
| /* Work with core dump and executable files, for GDB. |
| This code would be in corefile.c if it weren't machine-dependent. */ |
| |
| void |
| core_file_command (filename, from_tty) |
| char *filename; |
| int from_tty; |
| { |
| int val; |
| |
| /* Discard all vestiges of any previous core file |
| and mark data and stack spaces as empty. */ |
| |
| if (corefile) |
| free (corefile); |
| corefile = 0; |
| |
| if (corechan >= 0) |
| close (corechan); |
| corechan = -1; |
| |
| data_start = 0; |
| data_end = 0; |
| stack_start = STACK_END_ADDR; |
| stack_end = STACK_END_ADDR; |
| |
| #ifdef PYRAMID_CORE |
| reg_stack_start = CONTROL_STACK_ADDR; |
| reg_stack_end = CONTROL_STACK_ADDR; /* this isn't strictly true...*/ |
| #endif /* PYRAMID_CORE */ |
| |
| /* Now, if a new core file was specified, open it and digest it. */ |
| |
| if (filename) |
| { |
| filename = tilde_expand (filename); |
| make_cleanup (free, filename); |
| |
| if (have_inferior_p ()) |
| error ("To look at a core file, you must kill the program with \"kill\"."); |
| corechan = open (filename, O_RDONLY, 0); |
| if (corechan < 0) |
| perror_with_name (filename); |
| /* 4.2-style (and perhaps also sysV-style) core dump file. */ |
| { |
| struct user u; |
| |
| unsigned int reg_offset; |
| |
| val = myread (corechan, &u, sizeof u); |
| if (val < 0) |
| perror_with_name ("Not a core file: reading upage"); |
| if (val != sizeof u) |
| error ("Not a core file: could only read %d bytes", val); |
| data_start = exec_data_start; |
| |
| data_end = data_start + NBPG * u.u_dsize; |
| data_offset = NBPG * UPAGES; |
| stack_offset = NBPG * (UPAGES + u.u_dsize); |
| |
| /* find registers in core file */ |
| #ifdef PYRAMID_PTRACE |
| stack_start = stack_end - NBPG * u.u_ussize; |
| reg_stack_offset = stack_offset + (NBPG *u.u_ussize); |
| reg_stack_end = reg_stack_start + NBPG * u.u_cssize; |
| |
| last_frame_address = ((int) u.u_pcb.pcb_csp); |
| last_frame_offset = reg_stack_offset + last_frame_address |
| - CONTROL_STACK_ADDR ; |
| global_reg_offset = (char *)&u - (char *)&u.u_pcb.pcb_gr0 ; |
| |
| /* skip any control-stack frames that were executed in the |
| kernel. */ |
| |
| while (1) { |
| char buf[4]; |
| val = lseek (corechan, last_frame_offset+(47*4), 0); |
| if (val < 0) |
| perror_with_name (filename); |
| val = myread (corechan, buf, sizeof buf); |
| if (val < 0) |
| perror_with_name (filename); |
| |
| if (*(int *)buf >= 0) |
| break; |
| printf_unfiltered ("skipping frame %s\n", local_hex_string (last_frame_address)); |
| last_frame_offset -= CONTROL_STACK_FRAME_SIZE; |
| last_frame_address -= CONTROL_STACK_FRAME_SIZE; |
| } |
| reg_offset = last_frame_offset; |
| |
| #if 1 || defined(PYRAMID_CONTROL_FRAME_DEBUGGING) |
| printf_unfiltered ("Control stack pointer = %s\n", |
| local_hex_string (u.u_pcb.pcb_csp)); |
| printf_unfiltered ("offset to control stack %d outermost frame %d (%s)\n", |
| reg_stack_offset, reg_offset, local_hex_string (last_frame_address)); |
| #endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ |
| |
| #else /* not PYRAMID_CORE */ |
| stack_start = stack_end - NBPG * u.u_ssize; |
| reg_offset = (int) u.u_ar0 - KERNEL_U_ADDR; |
| #endif /* not PYRAMID_CORE */ |
| |
| #ifdef __not_on_pyr_yet |
| /* Some machines put an absolute address in here and some put |
| the offset in the upage of the regs. */ |
| reg_offset = (int) u.u_ar0; |
| if (reg_offset > NBPG * UPAGES) |
| reg_offset -= KERNEL_U_ADDR; |
| #endif |
| |
| /* I don't know where to find this info. |
| So, for now, mark it as not available. */ |
| N_SET_MAGIC (core_aouthdr, 0); |
| |
| /* Read the register values out of the core file and store |
| them where `read_register' will find them. */ |
| |
| { |
| register int regno; |
| |
| for (regno = 0; regno < 64; regno++) |
| { |
| char buf[MAX_REGISTER_RAW_SIZE]; |
| |
| val = lseek (corechan, register_addr (regno, reg_offset), 0); |
| if (val < 0 |
| || (val = myread (corechan, buf, sizeof buf)) < 0) |
| { |
| char * buffer = (char *) alloca (strlen (REGISTER_NAME (regno)) |
| + 30); |
| strcpy (buffer, "Reading register "); |
| strcat (buffer, REGISTER_NAME (regno)); |
| |
| perror_with_name (buffer); |
| } |
| |
| if (val < 0) |
| perror_with_name (filename); |
| #ifdef PYRAMID_CONTROL_FRAME_DEBUGGING |
| printf_unfiltered ("[reg %s(%d), offset in file %s=0x%0x, addr =0x%0x, =%0x]\n", |
| REGISTER_NAME (regno), regno, filename, |
| register_addr(regno, reg_offset), |
| regno * 4 + last_frame_address, |
| *((int *)buf)); |
| #endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ |
| supply_register (regno, buf); |
| } |
| } |
| } |
| if (filename[0] == '/') |
| corefile = savestring (filename, strlen (filename)); |
| else |
| { |
| corefile = concat (current_directory, "/", filename, NULL); |
| } |
| |
| #if 1 || defined(PYRAMID_CONTROL_FRAME_DEBUGGING) |
| printf_unfiltered ("Providing CSP (%s) as nominal address of current frame.\n", |
| local_hex_string(last_frame_address)); |
| #endif PYRAMID_CONTROL_FRAME_DEBUGGING |
| /* FIXME: Which of the following is correct? */ |
| #if 0 |
| set_current_frame ( create_new_frame (read_register (FP_REGNUM), |
| read_pc ())); |
| #else |
| set_current_frame ( create_new_frame (last_frame_address, |
| read_pc ())); |
| #endif |
| |
| select_frame (get_current_frame (), 0); |
| validate_files (); |
| } |
| else if (from_tty) |
| printf_unfiltered ("No core file now.\n"); |
| } |