| /* Native debugging support for Intel x86 running DJGPP. |
| Copyright (C) 1997-2024 Free Software Foundation, Inc. |
| Written by Robert Hoehne. |
| |
| 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 3 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, see <http://www.gnu.org/licenses/>. */ |
| |
| /* To whomever it may concern, here's a general description of how |
| debugging in DJGPP works, and the special quirks GDB does to |
| support that. |
| |
| When the DJGPP port of GDB is debugging a DJGPP program natively, |
| there aren't 2 separate processes, the debuggee and GDB itself, as |
| on other systems. (This is DOS, where there can only be one active |
| process at any given time, remember?) Instead, GDB and the |
| debuggee live in the same process. So when GDB calls |
| go32_create_inferior below, and that function calls edi_init from |
| the DJGPP debug support library libdbg.a, we load the debuggee's |
| executable file into GDB's address space, set it up for execution |
| as the stub loader (a short real-mode program prepended to each |
| DJGPP executable) normally would, and do a lot of preparations for |
| swapping between GDB's and debuggee's internal state, primarily wrt |
| the exception handlers. This swapping happens every time we resume |
| the debuggee or switch back to GDB's code, and it includes: |
| |
| . swapping all the segment registers |
| . swapping the PSP (the Program Segment Prefix) |
| . swapping the signal handlers |
| . swapping the exception handlers |
| . swapping the FPU status |
| . swapping the 3 standard file handles (more about this below) |
| |
| Then running the debuggee simply means longjmp into it where its PC |
| is and let it run until it stops for some reason. When it stops, |
| GDB catches the exception that stopped it and longjmp's back into |
| its own code. All the possible exit points of the debuggee are |
| watched; for example, the normal exit point is recognized because a |
| DOS program issues a special system call to exit. If one of those |
| exit points is hit, we mourn the inferior and clean up after it. |
| Cleaning up is very important, even if the process exits normally, |
| because otherwise we might leave behind traces of previous |
| execution, and in several cases GDB itself might be left hosed, |
| because all the exception handlers were not restored. |
| |
| Swapping of the standard handles (in redir_to_child and |
| redir_to_debugger) is needed because, since both GDB and the |
| debuggee live in the same process, as far as the OS is concerned, |
| the share the same file table. This means that the standard |
| handles 0, 1, and 2 point to the same file table entries, and thus |
| are connected to the same devices. Therefore, if the debugger |
| redirects its standard output, the standard output of the debuggee |
| is also automagically redirected to the same file/device! |
| Similarly, if the debuggee redirects its stdout to a file, you |
| won't be able to see debugger's output (it will go to the same file |
| where the debuggee has its output); and if the debuggee closes its |
| standard input, you will lose the ability to talk to debugger! |
| |
| For this reason, every time the debuggee is about to be resumed, we |
| call redir_to_child, which redirects the standard handles to where |
| the debuggee expects them to be. When the debuggee stops and GDB |
| regains control, we call redir_to_debugger, which redirects those 3 |
| handles back to where GDB expects. |
| |
| Note that only the first 3 handles are swapped, so if the debuggee |
| redirects or closes any other handles, GDB will not notice. In |
| particular, the exit code of a DJGPP program forcibly closes all |
| file handles beyond the first 3 ones, so when the debuggee exits, |
| GDB currently loses its stdaux and stdprn streams. Fortunately, |
| GDB does not use those as of this writing, and will never need |
| to. */ |
| |
| |
| #include <fcntl.h> |
| |
| #include "x86-nat.h" |
| #include "inferior.h" |
| #include "infrun.h" |
| #include "gdbthread.h" |
| #include "gdbsupport/gdb_wait.h" |
| #include "gdbcore.h" |
| #include "command.h" |
| #include "cli/cli-cmds.h" |
| #include "floatformat.h" |
| #include "buildsym-legacy.h" |
| #include "i387-tdep.h" |
| #include "i386-tdep.h" |
| #include "nat/x86-cpuid.h" |
| #include "value.h" |
| #include "regcache.h" |
| #include "top.h" |
| #include "cli/cli-utils.h" |
| #include "inf-child.h" |
| |
| #include <ctype.h> |
| #include <unistd.h> |
| #include <sys/utsname.h> |
| #include <io.h> |
| #include <dos.h> |
| #include <dpmi.h> |
| #include <go32.h> |
| #include <sys/farptr.h> |
| #include <debug/v2load.h> |
| #include <debug/dbgcom.h> |
| #if __DJGPP_MINOR__ > 2 |
| #include <debug/redir.h> |
| #endif |
| |
| #include <langinfo.h> |
| |
| #if __DJGPP_MINOR__ < 3 |
| /* This code will be provided from DJGPP 2.03 on. Until then I code it |
| here. */ |
| typedef struct |
| { |
| unsigned short sig0; |
| unsigned short sig1; |
| unsigned short sig2; |
| unsigned short sig3; |
| unsigned short exponent:15; |
| unsigned short sign:1; |
| } |
| NPXREG; |
| |
| typedef struct |
| { |
| unsigned int control; |
| unsigned int status; |
| unsigned int tag; |
| unsigned int eip; |
| unsigned int cs; |
| unsigned int dataptr; |
| unsigned int datasel; |
| NPXREG reg[8]; |
| } |
| NPX; |
| |
| static NPX npx; |
| |
| static void save_npx (void); /* Save the FPU of the debugged program. */ |
| static void load_npx (void); /* Restore the FPU of the debugged program. */ |
| |
| /* ------------------------------------------------------------------------- */ |
| /* Store the contents of the NPX in the global variable `npx'. */ |
| |
| static void |
| save_npx (void) |
| { |
| asm ("inb $0xa0, %%al \n\ |
| testb $0x20, %%al \n\ |
| jz 1f \n\ |
| xorb %%al, %%al \n\ |
| outb %%al, $0xf0 \n\ |
| movb $0x20, %%al \n\ |
| outb %%al, $0xa0 \n\ |
| outb %%al, $0x20 \n\ |
| 1: \n\ |
| fnsave %0 \n\ |
| fwait " |
| : "=m" (npx) |
| : /* No input */ |
| : "%eax"); |
| } |
| |
| |
| |
| /* ------------------------------------------------------------------------- */ |
| /* Reload the contents of the NPX from the global variable `npx'. */ |
| |
| static void |
| load_npx (void) |
| { |
| asm ("frstor %0":"=m" (npx)); |
| } |
| /* ------------------------------------------------------------------------- */ |
| /* Stubs for the missing redirection functions. */ |
| typedef struct { |
| char *command; |
| int redirected; |
| } cmdline_t; |
| |
| void |
| redir_cmdline_delete (cmdline_t *ptr) |
| { |
| ptr->redirected = 0; |
| } |
| |
| int |
| redir_cmdline_parse (const char *args, cmdline_t *ptr) |
| { |
| return -1; |
| } |
| |
| int |
| redir_to_child (cmdline_t *ptr) |
| { |
| return 1; |
| } |
| |
| int |
| redir_to_debugger (cmdline_t *ptr) |
| { |
| return 1; |
| } |
| |
| int |
| redir_debug_init (cmdline_t *ptr) |
| { |
| return 0; |
| } |
| #endif /* __DJGPP_MINOR < 3 */ |
| |
| typedef enum { wp_insert, wp_remove, wp_count } wp_op; |
| |
| /* This holds the current reference counts for each debug register. */ |
| static int dr_ref_count[4]; |
| |
| #define SOME_PID 42 |
| |
| static int prog_has_started = 0; |
| |
| #define r_ofs(x) (offsetof(TSS,x)) |
| |
| static struct |
| { |
| size_t tss_ofs; |
| size_t size; |
| } |
| regno_mapping[] = |
| { |
| {r_ofs (tss_eax), 4}, /* normal registers, from a_tss */ |
| {r_ofs (tss_ecx), 4}, |
| {r_ofs (tss_edx), 4}, |
| {r_ofs (tss_ebx), 4}, |
| {r_ofs (tss_esp), 4}, |
| {r_ofs (tss_ebp), 4}, |
| {r_ofs (tss_esi), 4}, |
| {r_ofs (tss_edi), 4}, |
| {r_ofs (tss_eip), 4}, |
| {r_ofs (tss_eflags), 4}, |
| {r_ofs (tss_cs), 2}, |
| {r_ofs (tss_ss), 2}, |
| {r_ofs (tss_ds), 2}, |
| {r_ofs (tss_es), 2}, |
| {r_ofs (tss_fs), 2}, |
| {r_ofs (tss_gs), 2}, |
| {0, 10}, /* 8 FP registers, from npx.reg[] */ |
| {1, 10}, |
| {2, 10}, |
| {3, 10}, |
| {4, 10}, |
| {5, 10}, |
| {6, 10}, |
| {7, 10}, |
| /* The order of the next 7 registers must be consistent |
| with their numbering in config/i386/tm-i386.h, which see. */ |
| {0, 2}, /* control word, from npx */ |
| {4, 2}, /* status word, from npx */ |
| {8, 2}, /* tag word, from npx */ |
| {16, 2}, /* last FP exception CS from npx */ |
| {12, 4}, /* last FP exception EIP from npx */ |
| {24, 2}, /* last FP exception operand selector from npx */ |
| {20, 4}, /* last FP exception operand offset from npx */ |
| {18, 2} /* last FP opcode from npx */ |
| }; |
| |
| static struct |
| { |
| int go32_sig; |
| enum gdb_signal gdb_sig; |
| } |
| sig_map[] = |
| { |
| {0, GDB_SIGNAL_FPE}, |
| {1, GDB_SIGNAL_TRAP}, |
| /* Exception 2 is triggered by the NMI. DJGPP handles it as SIGILL, |
| but I think SIGBUS is better, since the NMI is usually activated |
| as a result of a memory parity check failure. */ |
| {2, GDB_SIGNAL_BUS}, |
| {3, GDB_SIGNAL_TRAP}, |
| {4, GDB_SIGNAL_FPE}, |
| {5, GDB_SIGNAL_SEGV}, |
| {6, GDB_SIGNAL_ILL}, |
| {7, GDB_SIGNAL_EMT}, /* no-coprocessor exception */ |
| {8, GDB_SIGNAL_SEGV}, |
| {9, GDB_SIGNAL_SEGV}, |
| {10, GDB_SIGNAL_BUS}, |
| {11, GDB_SIGNAL_SEGV}, |
| {12, GDB_SIGNAL_SEGV}, |
| {13, GDB_SIGNAL_SEGV}, |
| {14, GDB_SIGNAL_SEGV}, |
| {16, GDB_SIGNAL_FPE}, |
| {17, GDB_SIGNAL_BUS}, |
| {31, GDB_SIGNAL_ILL}, |
| {0x1b, GDB_SIGNAL_INT}, |
| {0x75, GDB_SIGNAL_FPE}, |
| {0x78, GDB_SIGNAL_ALRM}, |
| {0x79, GDB_SIGNAL_INT}, |
| {0x7a, GDB_SIGNAL_QUIT}, |
| {-1, GDB_SIGNAL_LAST} |
| }; |
| |
| static struct { |
| enum gdb_signal gdb_sig; |
| int djgpp_excepno; |
| } excepn_map[] = { |
| {GDB_SIGNAL_0, -1}, |
| {GDB_SIGNAL_ILL, 6}, /* Invalid Opcode */ |
| {GDB_SIGNAL_EMT, 7}, /* triggers SIGNOFP */ |
| {GDB_SIGNAL_SEGV, 13}, /* GPF */ |
| {GDB_SIGNAL_BUS, 17}, /* Alignment Check */ |
| /* The rest are fake exceptions, see dpmiexcp.c in djlsr*.zip for |
| details. */ |
| {GDB_SIGNAL_TERM, 0x1b}, /* triggers Ctrl-Break type of SIGINT */ |
| {GDB_SIGNAL_FPE, 0x75}, |
| {GDB_SIGNAL_INT, 0x79}, |
| {GDB_SIGNAL_QUIT, 0x7a}, |
| {GDB_SIGNAL_ALRM, 0x78}, /* triggers SIGTIMR */ |
| {GDB_SIGNAL_PROF, 0x78}, |
| {GDB_SIGNAL_LAST, -1} |
| }; |
| |
| /* The go32 target. */ |
| |
| struct go32_nat_target final : public x86_nat_target<inf_child_target> |
| { |
| void attach (const char *, int) override; |
| |
| void resume (ptid_t, int, enum gdb_signal) override; |
| |
| ptid_t wait (ptid_t, struct target_waitstatus *, target_wait_flags) override; |
| |
| void fetch_registers (struct regcache *, int) override; |
| void store_registers (struct regcache *, int) override; |
| |
| enum target_xfer_status xfer_partial (enum target_object object, |
| const char *annex, |
| gdb_byte *readbuf, |
| const gdb_byte *writebuf, |
| ULONGEST offset, ULONGEST len, |
| ULONGEST *xfered_len) override; |
| |
| void files_info () override; |
| |
| void terminal_init () override; |
| |
| void terminal_inferior () override; |
| |
| void terminal_ours_for_output () override; |
| |
| void terminal_ours () override; |
| |
| void terminal_info (const char *, int) override; |
| |
| void pass_ctrlc () override; |
| |
| void kill () override; |
| |
| void create_inferior (const char *, const std::string &, |
| char **, int) override; |
| |
| void mourn_inferior () override; |
| |
| bool thread_alive (ptid_t ptid) override; |
| |
| std::string pid_to_str (ptid_t) override; |
| }; |
| |
| static go32_nat_target the_go32_nat_target; |
| |
| void |
| go32_nat_target::attach (const char *args, int from_tty) |
| { |
| error (_("\ |
| You cannot attach to a running program on this platform.\n\ |
| Use the `run' command to run DJGPP programs.")); |
| } |
| |
| static int resume_is_step; |
| static int resume_signal = -1; |
| |
| void |
| go32_nat_target::resume (ptid_t ptid, int step, enum gdb_signal siggnal) |
| { |
| int i; |
| |
| resume_is_step = step; |
| |
| if (siggnal != GDB_SIGNAL_0 && siggnal != GDB_SIGNAL_TRAP) |
| { |
| for (i = 0, resume_signal = -1; |
| excepn_map[i].gdb_sig != GDB_SIGNAL_LAST; i++) |
| if (excepn_map[i].gdb_sig == siggnal) |
| { |
| resume_signal = excepn_map[i].djgpp_excepno; |
| break; |
| } |
| if (resume_signal == -1) |
| printf_unfiltered ("Cannot deliver signal %s on this platform.\n", |
| gdb_signal_to_name (siggnal)); |
| } |
| } |
| |
| static char child_cwd[FILENAME_MAX]; |
| |
| ptid_t |
| go32_nat_target::wait (ptid_t ptid, struct target_waitstatus *status, |
| target_wait_flags options) |
| { |
| int i; |
| unsigned char saved_opcode; |
| unsigned long INT3_addr = 0; |
| int stepping_over_INT = 0; |
| |
| a_tss.tss_eflags &= 0xfeff; /* Reset the single-step flag (TF). */ |
| if (resume_is_step) |
| { |
| /* If the next instruction is INT xx or INTO, we need to handle |
| them specially. Intel manuals say that these instructions |
| reset the single-step flag (a.k.a. TF). However, it seems |
| that, at least in the DPMI environment, and at least when |
| stepping over the DPMI interrupt 31h, the problem is having |
| TF set at all when INT 31h is executed: the debuggee either |
| crashes (and takes the system with it) or is killed by a |
| SIGTRAP. |
| |
| So we need to emulate single-step mode: we put an INT3 opcode |
| right after the INT xx instruction, let the debuggee run |
| until it hits INT3 and stops, then restore the original |
| instruction which we overwrote with the INT3 opcode, and back |
| up the debuggee's EIP to that instruction. */ |
| read_child (a_tss.tss_eip, &saved_opcode, 1); |
| if (saved_opcode == 0xCD || saved_opcode == 0xCE) |
| { |
| unsigned char INT3_opcode = 0xCC; |
| |
| INT3_addr |
| = saved_opcode == 0xCD ? a_tss.tss_eip + 2 : a_tss.tss_eip + 1; |
| stepping_over_INT = 1; |
| read_child (INT3_addr, &saved_opcode, 1); |
| write_child (INT3_addr, &INT3_opcode, 1); |
| } |
| else |
| a_tss.tss_eflags |= 0x0100; /* normal instruction: set TF */ |
| } |
| |
| /* The special value FFFFh in tss_trap indicates to run_child that |
| tss_irqn holds a signal to be delivered to the debuggee. */ |
| if (resume_signal <= -1) |
| { |
| a_tss.tss_trap = 0; |
| a_tss.tss_irqn = 0xff; |
| } |
| else |
| { |
| a_tss.tss_trap = 0xffff; /* run_child looks for this. */ |
| a_tss.tss_irqn = resume_signal; |
| } |
| |
| /* The child might change working directory behind our back. The |
| GDB users won't like the side effects of that when they work with |
| relative file names, and GDB might be confused by its current |
| directory not being in sync with the truth. So we always make a |
| point of changing back to where GDB thinks is its cwd, when we |
| return control to the debugger, but restore child's cwd before we |
| run it. */ |
| /* Initialize child_cwd, before the first call to run_child and not |
| in the initialization, so the child get also the changed directory |
| set with the gdb-command "cd ..." */ |
| if (!*child_cwd) |
| /* Initialize child's cwd with the current one. */ |
| getcwd (child_cwd, sizeof (child_cwd)); |
| |
| chdir (child_cwd); |
| |
| #if __DJGPP_MINOR__ < 3 |
| load_npx (); |
| #endif |
| run_child (); |
| #if __DJGPP_MINOR__ < 3 |
| save_npx (); |
| #endif |
| |
| /* Did we step over an INT xx instruction? */ |
| if (stepping_over_INT && a_tss.tss_eip == INT3_addr + 1) |
| { |
| /* Restore the original opcode. */ |
| a_tss.tss_eip--; /* EIP points *after* the INT3 instruction. */ |
| write_child (a_tss.tss_eip, &saved_opcode, 1); |
| /* Simulate a TRAP exception. */ |
| a_tss.tss_irqn = 1; |
| a_tss.tss_eflags |= 0x0100; |
| } |
| |
| getcwd (child_cwd, sizeof (child_cwd)); /* in case it has changed */ |
| if (current_directory != NULL) |
| chdir (current_directory); |
| |
| if (a_tss.tss_irqn == 0x21) |
| status->set_exited (a_tss.tss_eax & 0xff); |
| else |
| { |
| status->set_stopped (GDB_SIGNAL_UNKNOWN); |
| for (i = 0; sig_map[i].go32_sig != -1; i++) |
| { |
| if (a_tss.tss_irqn == sig_map[i].go32_sig) |
| { |
| #if __DJGPP_MINOR__ < 3 |
| status->set_stopped (sig_map[i].gdb_sig); |
| if (status->sig () != GDB_SIGNAL_TRAP) |
| status->set_signalled (status->sig ()); |
| #else |
| status->set_stopped (sig_map[i].gdb_sig); |
| #endif |
| break; |
| } |
| } |
| } |
| return ptid_t (SOME_PID); |
| } |
| |
| static void |
| fetch_register (struct regcache *regcache, int regno) |
| { |
| struct gdbarch *gdbarch = regcache->arch (); |
| if (regno < gdbarch_fp0_regnum (gdbarch)) |
| regcache->raw_supply (regno, |
| (char *) &a_tss + regno_mapping[regno].tss_ofs); |
| else if (i386_fp_regnum_p (gdbarch, regno) || i386_fpc_regnum_p (gdbarch, |
| regno)) |
| i387_supply_fsave (regcache, regno, &npx); |
| else |
| internal_error (_("Invalid register no. %d in fetch_register."), regno); |
| } |
| |
| void |
| go32_nat_target::fetch_registers (struct regcache *regcache, int regno) |
| { |
| if (regno >= 0) |
| fetch_register (regcache, regno); |
| else |
| { |
| for (regno = 0; |
| regno < gdbarch_fp0_regnum (regcache->arch ()); |
| regno++) |
| fetch_register (regcache, regno); |
| i387_supply_fsave (regcache, -1, &npx); |
| } |
| } |
| |
| static void |
| store_register (const struct regcache *regcache, int regno) |
| { |
| struct gdbarch *gdbarch = regcache->arch (); |
| if (regno < gdbarch_fp0_regnum (gdbarch)) |
| regcache->raw_collect (regno, |
| (char *) &a_tss + regno_mapping[regno].tss_ofs); |
| else if (i386_fp_regnum_p (gdbarch, regno) || i386_fpc_regnum_p (gdbarch, |
| regno)) |
| i387_collect_fsave (regcache, regno, &npx); |
| else |
| internal_error (_("Invalid register no. %d in store_register."), regno); |
| } |
| |
| void |
| go32_nat_target::store_registers (struct regcache *regcache, int regno) |
| { |
| unsigned r; |
| |
| if (regno >= 0) |
| store_register (regcache, regno); |
| else |
| { |
| for (r = 0; r < gdbarch_fp0_regnum (regcache->arch ()); r++) |
| store_register (regcache, r); |
| i387_collect_fsave (regcache, -1, &npx); |
| } |
| } |
| |
| /* Const-correct version of DJGPP's write_child, which unfortunately |
| takes a non-const buffer pointer. */ |
| |
| static int |
| my_write_child (unsigned child_addr, const void *buf, unsigned len) |
| { |
| static void *buffer = NULL; |
| static unsigned buffer_len = 0; |
| int res; |
| |
| if (buffer_len < len) |
| { |
| buffer = xrealloc (buffer, len); |
| buffer_len = len; |
| } |
| |
| memcpy (buffer, buf, len); |
| res = write_child (child_addr, buffer, len); |
| return res; |
| } |
| |
| /* Helper for go32_xfer_partial that handles memory transfers. |
| Arguments are like target_xfer_partial. */ |
| |
| static enum target_xfer_status |
| go32_xfer_memory (gdb_byte *readbuf, const gdb_byte *writebuf, |
| ULONGEST memaddr, ULONGEST len, ULONGEST *xfered_len) |
| { |
| int res; |
| |
| if (writebuf != NULL) |
| res = my_write_child (memaddr, writebuf, len); |
| else |
| res = read_child (memaddr, readbuf, len); |
| |
| /* read_child and write_child return zero on success, non-zero on |
| failure. */ |
| if (res != 0) |
| return TARGET_XFER_E_IO; |
| |
| *xfered_len = len; |
| return TARGET_XFER_OK; |
| } |
| |
| /* Target to_xfer_partial implementation. */ |
| |
| enum target_xfer_status |
| go32_nat_target::xfer_partial (enum target_object object, |
| const char *annex, gdb_byte *readbuf, |
| const gdb_byte *writebuf, ULONGEST offset, |
| ULONGEST len, |
| ULONGEST *xfered_len) |
| { |
| switch (object) |
| { |
| case TARGET_OBJECT_MEMORY: |
| return go32_xfer_memory (readbuf, writebuf, offset, len, xfered_len); |
| |
| default: |
| return this->beneath ()->xfer_partial (object, annex, |
| readbuf, writebuf, offset, len, |
| xfered_len); |
| } |
| } |
| |
| static cmdline_t child_cmd; /* Parsed child's command line kept here. */ |
| |
| void |
| go32_nat_target::files_info () |
| { |
| gdb_printf ("You are running a DJGPP V2 program.\n"); |
| } |
| |
| void |
| go32_nat_target::kill_inferior () |
| { |
| mourn_inferior (); |
| } |
| |
| void |
| go32_nat_target::create_inferior (const char *exec_file, |
| const std::string &allargs, |
| char **env, int from_tty) |
| { |
| extern char **environ; |
| jmp_buf start_state; |
| char *cmdline; |
| char **env_save = environ; |
| size_t cmdlen; |
| struct inferior *inf; |
| int result; |
| const char *args = allargs.c_str (); |
| |
| if (exec_file == nullptr) |
| no_executable_specified_error (); |
| |
| resume_signal = -1; |
| resume_is_step = 0; |
| |
| /* Initialize child's cwd as empty to be initialized when starting |
| the child. */ |
| *child_cwd = 0; |
| |
| /* Init command line storage. */ |
| if (redir_debug_init (&child_cmd) == -1) |
| internal_error (_("Cannot allocate redirection storage: " |
| "not enough memory.\n")); |
| |
| /* Parse the command line and create redirections. */ |
| if (strpbrk (args, "<>")) |
| { |
| if (redir_cmdline_parse (args, &child_cmd) == 0) |
| args = child_cmd.command; |
| else |
| error (_("Syntax error in command line.")); |
| } |
| else |
| child_cmd.command = xstrdup (args); |
| |
| cmdlen = strlen (args); |
| /* v2loadimage passes command lines via DOS memory, so it cannot |
| possibly handle commands longer than 1MB. */ |
| if (cmdlen > 1024*1024) |
| error (_("Command line too long.")); |
| |
| cmdline = (char *) xmalloc (cmdlen + 4); |
| strcpy (cmdline + 1, args); |
| /* If the command-line length fits into DOS 126-char limits, use the |
| DOS command tail format; otherwise, tell v2loadimage to pass it |
| through a buffer in conventional memory. */ |
| if (cmdlen < 127) |
| { |
| cmdline[0] = strlen (args); |
| cmdline[cmdlen + 1] = 13; |
| } |
| else |
| cmdline[0] = 0xff; /* Signal v2loadimage it's a long command. */ |
| |
| environ = env; |
| |
| result = v2loadimage (exec_file, cmdline, start_state); |
| |
| environ = env_save; |
| xfree (cmdline); |
| |
| if (result != 0) |
| error (_("Load failed for image %s"), exec_file); |
| |
| edi_init (start_state); |
| #if __DJGPP_MINOR__ < 3 |
| save_npx (); |
| #endif |
| |
| inf = current_inferior (); |
| inferior_appeared (inf, SOME_PID); |
| |
| if (!inf->target_is_pushed (this)) |
| inf->push_target (this); |
| |
| thread_info *thr = add_thread_silent (ptid_t (SOME_PID)); |
| switch_to_thread (thr); |
| |
| clear_proceed_status (0); |
| insert_breakpoints (); |
| prog_has_started = 1; |
| } |
| |
| void |
| go32_nat_target::mourn_inferior () |
| { |
| redir_cmdline_delete (&child_cmd); |
| resume_signal = -1; |
| resume_is_step = 0; |
| |
| cleanup_client (); |
| |
| /* We need to make sure all the breakpoint enable bits in the DR7 |
| register are reset when the inferior exits. Otherwise, if they |
| rerun the inferior, the uncleared bits may cause random SIGTRAPs, |
| failure to set more watchpoints, and other calamities. It would |
| be nice if GDB itself would take care to remove all breakpoints |
| at all times, but it doesn't, probably under an assumption that |
| the OS cleans up when the debuggee exits. */ |
| x86_cleanup_dregs (); |
| |
| prog_has_started = 0; |
| |
| generic_mourn_inferior (); |
| maybe_unpush_target (); |
| } |
| |
| /* Hardware watchpoint support. */ |
| |
| #define D_REGS edi.dr |
| #define CONTROL D_REGS[7] |
| #define STATUS D_REGS[6] |
| |
| /* Pass the address ADDR to the inferior in the I'th debug register. |
| Here we just store the address in D_REGS, the watchpoint will be |
| actually set up when go32_wait runs the debuggee. */ |
| static void |
| go32_set_dr (int i, CORE_ADDR addr) |
| { |
| if (i < 0 || i > 3) |
| internal_error (_("Invalid register %d in go32_set_dr.\n"), i); |
| D_REGS[i] = addr; |
| } |
| |
| /* Pass the value VAL to the inferior in the DR7 debug control |
| register. Here we just store the address in D_REGS, the watchpoint |
| will be actually set up when go32_wait runs the debuggee. */ |
| static void |
| go32_set_dr7 (unsigned long val) |
| { |
| CONTROL = val; |
| } |
| |
| /* Get the value of the DR6 debug status register from the inferior. |
| Here we just return the value stored in D_REGS, as we've got it |
| from the last go32_wait call. */ |
| static unsigned long |
| go32_get_dr6 (void) |
| { |
| return STATUS; |
| } |
| |
| /* Get the value of the DR7 debug status register from the inferior. |
| Here we just return the value stored in D_REGS, as we've got it |
| from the last go32_wait call. */ |
| |
| static unsigned long |
| go32_get_dr7 (void) |
| { |
| return CONTROL; |
| } |
| |
| /* Get the value of the DR debug register I from the inferior. Here |
| we just return the value stored in D_REGS, as we've got it from the |
| last go32_wait call. */ |
| |
| static CORE_ADDR |
| go32_get_dr (int i) |
| { |
| if (i < 0 || i > 3) |
| internal_error (_("Invalid register %d in go32_get_dr.\n"), i); |
| return D_REGS[i]; |
| } |
| |
| /* Put the device open on handle FD into either raw or cooked |
| mode, return 1 if it was in raw mode, zero otherwise. */ |
| |
| static int |
| device_mode (int fd, int raw_p) |
| { |
| int oldmode, newmode; |
| __dpmi_regs regs; |
| |
| regs.x.ax = 0x4400; |
| regs.x.bx = fd; |
| __dpmi_int (0x21, ®s); |
| if (regs.x.flags & 1) |
| return -1; |
| newmode = oldmode = regs.x.dx; |
| |
| if (raw_p) |
| newmode |= 0x20; |
| else |
| newmode &= ~0x20; |
| |
| if (oldmode & 0x80) /* Only for character dev. */ |
| { |
| regs.x.ax = 0x4401; |
| regs.x.bx = fd; |
| regs.x.dx = newmode & 0xff; /* Force upper byte zero, else it fails. */ |
| __dpmi_int (0x21, ®s); |
| if (regs.x.flags & 1) |
| return -1; |
| } |
| return (oldmode & 0x20) == 0x20; |
| } |
| |
| |
| static int inf_mode_valid = 0; |
| static int inf_terminal_mode; |
| |
| /* This semaphore is needed because, amazingly enough, GDB calls |
| target.to_terminal_ours more than once after the inferior stops. |
| But we need the information from the first call only, since the |
| second call will always see GDB's own cooked terminal. */ |
| static int terminal_is_ours = 1; |
| |
| void |
| go32_nat_target::terminal_init () |
| { |
| inf_mode_valid = 0; /* Reinitialize, in case they are restarting child. */ |
| terminal_is_ours = 1; |
| } |
| |
| void |
| go32_nat_target::terminal_info (const char *args, int from_tty) |
| { |
| gdb_printf ("Inferior's terminal is in %s mode.\n", |
| !inf_mode_valid |
| ? "default" : inf_terminal_mode ? "raw" : "cooked"); |
| |
| #if __DJGPP_MINOR__ > 2 |
| if (child_cmd.redirection) |
| { |
| int i; |
| |
| for (i = 0; i < DBG_HANDLES; i++) |
| { |
| if (child_cmd.redirection[i]->file_name) |
| gdb_printf ("\tFile handle %d is redirected to `%s'.\n", |
| i, child_cmd.redirection[i]->file_name); |
| else if (_get_dev_info (child_cmd.redirection[i]->inf_handle) == -1) |
| gdb_printf |
| ("\tFile handle %d appears to be closed by inferior.\n", i); |
| /* Mask off the raw/cooked bit when comparing device info words. */ |
| else if ((_get_dev_info (child_cmd.redirection[i]->inf_handle) & 0xdf) |
| != (_get_dev_info (i) & 0xdf)) |
| gdb_printf |
| ("\tFile handle %d appears to be redirected by inferior.\n", i); |
| } |
| } |
| #endif |
| } |
| |
| void |
| go32_nat_target::terminal_inferior () |
| { |
| /* Redirect standard handles as child wants them. */ |
| errno = 0; |
| if (redir_to_child (&child_cmd) == -1) |
| { |
| redir_to_debugger (&child_cmd); |
| error (_("Cannot redirect standard handles for program: %s."), |
| safe_strerror (errno)); |
| } |
| /* Set the console device of the inferior to whatever mode |
| (raw or cooked) we found it last time. */ |
| if (terminal_is_ours) |
| { |
| if (inf_mode_valid) |
| device_mode (0, inf_terminal_mode); |
| terminal_is_ours = 0; |
| } |
| } |
| |
| void |
| go32_nat_target::terminal_ours () |
| { |
| /* Switch to cooked mode on the gdb terminal and save the inferior |
| terminal mode to be restored when it is resumed. */ |
| if (!terminal_is_ours) |
| { |
| inf_terminal_mode = device_mode (0, 0); |
| if (inf_terminal_mode != -1) |
| inf_mode_valid = 1; |
| else |
| /* If device_mode returned -1, we don't know what happens with |
| handle 0 anymore, so make the info invalid. */ |
| inf_mode_valid = 0; |
| terminal_is_ours = 1; |
| |
| /* Restore debugger's standard handles. */ |
| errno = 0; |
| if (redir_to_debugger (&child_cmd) == -1) |
| { |
| redir_to_child (&child_cmd); |
| error (_("Cannot redirect standard handles for debugger: %s."), |
| safe_strerror (errno)); |
| } |
| } |
| } |
| |
| void |
| go32_nat_target::pass_ctrlc () |
| { |
| } |
| |
| bool |
| go32_nat_target::thread_alive (ptid_t ptid) |
| { |
| return ptid != null_ptid; |
| } |
| |
| std::string |
| go32_nat_target::pid_to_str (ptid_t ptid) |
| { |
| return normal_pid_to_str (ptid); |
| } |
| |
| /* Return the current DOS codepage number. */ |
| static int |
| dos_codepage (void) |
| { |
| __dpmi_regs regs; |
| |
| regs.x.ax = 0x6601; |
| __dpmi_int (0x21, ®s); |
| if (!(regs.x.flags & 1)) |
| return regs.x.bx & 0xffff; |
| else |
| return 437; /* default */ |
| } |
| |
| /* Limited emulation of `nl_langinfo', for charset.c. */ |
| char * |
| nl_langinfo (nl_item item) |
| { |
| char *retval; |
| |
| switch (item) |
| { |
| case CODESET: |
| { |
| /* 8 is enough for SHORT_MAX + "CP" + null. */ |
| char buf[8]; |
| int blen = sizeof (buf); |
| int needed = snprintf (buf, blen, "CP%d", dos_codepage ()); |
| |
| if (needed > blen) /* Should never happen. */ |
| buf[0] = 0; |
| retval = xstrdup (buf); |
| } |
| break; |
| default: |
| retval = xstrdup (""); |
| break; |
| } |
| return retval; |
| } |
| |
| unsigned short windows_major, windows_minor; |
| |
| /* Compute the version Windows reports via Int 2Fh/AX=1600h. */ |
| static void |
| go32_get_windows_version(void) |
| { |
| __dpmi_regs r; |
| |
| r.x.ax = 0x1600; |
| __dpmi_int(0x2f, &r); |
| if (r.h.al > 2 && r.h.al != 0x80 && r.h.al != 0xff |
| && (r.h.al > 3 || r.h.ah > 0)) |
| { |
| windows_major = r.h.al; |
| windows_minor = r.h.ah; |
| } |
| else |
| windows_major = 0xff; /* meaning no Windows */ |
| } |
| |
| /* A subroutine of go32_sysinfo to display memory info. */ |
| static void |
| print_mem (unsigned long datum, const char *header, int in_pages_p) |
| { |
| if (datum != 0xffffffffUL) |
| { |
| if (in_pages_p) |
| datum <<= 12; |
| gdb_puts (header); |
| if (datum > 1024) |
| { |
| gdb_printf ("%lu KB", datum >> 10); |
| if (datum > 1024 * 1024) |
| gdb_printf (" (%lu MB)", datum >> 20); |
| } |
| else |
| gdb_printf ("%lu Bytes", datum); |
| gdb_puts ("\n"); |
| } |
| } |
| |
| /* Display assorted information about the underlying OS. */ |
| static void |
| go32_sysinfo (const char *arg, int from_tty) |
| { |
| static const char test_pattern[] = |
| "deadbeafdeadbeafdeadbeafdeadbeafdeadbeaf" |
| "deadbeafdeadbeafdeadbeafdeadbeafdeadbeaf" |
| "deadbeafdeadbeafdeadbeafdeadbeafdeadbeafdeadbeaf"; |
| struct utsname u; |
| char cpuid_vendor[13]; |
| unsigned cpuid_max = 0, cpuid_eax, cpuid_ebx, cpuid_ecx, cpuid_edx; |
| unsigned true_dos_version = _get_dos_version (1); |
| unsigned advertized_dos_version = ((unsigned int)_osmajor << 8) | _osminor; |
| int dpmi_flags; |
| char dpmi_vendor_info[129]; |
| int dpmi_vendor_available; |
| __dpmi_version_ret dpmi_version_data; |
| long eflags; |
| __dpmi_free_mem_info mem_info; |
| __dpmi_regs regs; |
| |
| cpuid_vendor[0] = '\0'; |
| if (uname (&u)) |
| strcpy (u.machine, "Unknown x86"); |
| else if (u.machine[0] == 'i' && u.machine[1] > 4) |
| { |
| /* CPUID with EAX = 0 returns the Vendor ID. */ |
| #if 0 |
| /* Ideally we would use x86_cpuid(), but it needs someone to run |
| native tests first to make sure things actually work. They should. |
| http://sourceware.org/ml/gdb-patches/2013-05/msg00164.html */ |
| unsigned int eax, ebx, ecx, edx; |
| |
| if (x86_cpuid (0, &eax, &ebx, &ecx, &edx)) |
| { |
| cpuid_max = eax; |
| memcpy (&vendor[0], &ebx, 4); |
| memcpy (&vendor[4], &ecx, 4); |
| memcpy (&vendor[8], &edx, 4); |
| cpuid_vendor[12] = '\0'; |
| } |
| #else |
| __asm__ __volatile__ ("xorl %%ebx, %%ebx;" |
| "xorl %%ecx, %%ecx;" |
| "xorl %%edx, %%edx;" |
| "movl $0, %%eax;" |
| "cpuid;" |
| "movl %%ebx, %0;" |
| "movl %%edx, %1;" |
| "movl %%ecx, %2;" |
| "movl %%eax, %3;" |
| : "=m" (cpuid_vendor[0]), |
| "=m" (cpuid_vendor[4]), |
| "=m" (cpuid_vendor[8]), |
| "=m" (cpuid_max) |
| : |
| : "%eax", "%ebx", "%ecx", "%edx"); |
| cpuid_vendor[12] = '\0'; |
| #endif |
| } |
| |
| gdb_printf ("CPU Type.......................%s", u.machine); |
| if (cpuid_vendor[0]) |
| gdb_printf (" (%s)", cpuid_vendor); |
| gdb_puts ("\n"); |
| |
| /* CPUID with EAX = 1 returns processor signature and features. */ |
| if (cpuid_max >= 1) |
| { |
| static const char *brand_name[] = { |
| "", |
| " Celeron", |
| " III", |
| " III Xeon", |
| "", "", "", "", |
| " 4" |
| }; |
| char cpu_string[80]; |
| char cpu_brand[20]; |
| unsigned brand_idx; |
| int intel_p = strcmp (cpuid_vendor, "GenuineIntel") == 0; |
| int amd_p = strcmp (cpuid_vendor, "AuthenticAMD") == 0; |
| int hygon_p = strcmp (cpuid_vendor, "HygonGenuine") == 0; |
| unsigned cpu_family, cpu_model; |
| |
| #if 0 |
| /* See comment above about cpuid usage. */ |
| x86_cpuid (1, &cpuid_eax, &cpuid_ebx, NULL, &cpuid_edx); |
| #else |
| __asm__ __volatile__ ("movl $1, %%eax;" |
| "cpuid;" |
| : "=a" (cpuid_eax), |
| "=b" (cpuid_ebx), |
| "=d" (cpuid_edx) |
| : |
| : "%ecx"); |
| #endif |
| brand_idx = cpuid_ebx & 0xff; |
| cpu_family = (cpuid_eax >> 8) & 0xf; |
| cpu_model = (cpuid_eax >> 4) & 0xf; |
| cpu_brand[0] = '\0'; |
| if (intel_p) |
| { |
| if (brand_idx > 0 |
| && brand_idx < sizeof(brand_name)/sizeof(brand_name[0]) |
| && *brand_name[brand_idx]) |
| strcpy (cpu_brand, brand_name[brand_idx]); |
| else if (cpu_family == 5) |
| { |
| if (((cpuid_eax >> 12) & 3) == 0 && cpu_model == 4) |
| strcpy (cpu_brand, " MMX"); |
| else if (cpu_model > 1 && ((cpuid_eax >> 12) & 3) == 1) |
| strcpy (cpu_brand, " OverDrive"); |
| else if (cpu_model > 1 && ((cpuid_eax >> 12) & 3) == 2) |
| strcpy (cpu_brand, " Dual"); |
| } |
| else if (cpu_family == 6 && cpu_model < 8) |
| { |
| switch (cpu_model) |
| { |
| case 1: |
| strcpy (cpu_brand, " Pro"); |
| break; |
| case 3: |
| strcpy (cpu_brand, " II"); |
| break; |
| case 5: |
| strcpy (cpu_brand, " II Xeon"); |
| break; |
| case 6: |
| strcpy (cpu_brand, " Celeron"); |
| break; |
| case 7: |
| strcpy (cpu_brand, " III"); |
| break; |
| } |
| } |
| } |
| else if (amd_p) |
| { |
| switch (cpu_family) |
| { |
| case 4: |
| strcpy (cpu_brand, "486/5x86"); |
| break; |
| case 5: |
| switch (cpu_model) |
| { |
| case 0: |
| case 1: |
| case 2: |
| case 3: |
| strcpy (cpu_brand, "-K5"); |
| break; |
| case 6: |
| case 7: |
| strcpy (cpu_brand, "-K6"); |
| break; |
| case 8: |
| strcpy (cpu_brand, "-K6-2"); |
| break; |
| case 9: |
| strcpy (cpu_brand, "-K6-III"); |
| break; |
| } |
| break; |
| case 6: |
| switch (cpu_model) |
| { |
| case 1: |
| case 2: |
| case 4: |
| strcpy (cpu_brand, " Athlon"); |
| break; |
| case 3: |
| strcpy (cpu_brand, " Duron"); |
| break; |
| } |
| break; |
| } |
| } |
| xsnprintf (cpu_string, sizeof (cpu_string), "%s%s Model %d Stepping %d", |
| intel_p ? "Pentium" : (amd_p ? "AMD" : (hygon_p ? "Hygon" : "ix86")), |
| cpu_brand, cpu_model, cpuid_eax & 0xf); |
| gdb_printf ("%*s%s\n", 31, "", cpu_string); |
| if (((cpuid_edx & (6 | (0x0d << 23))) != 0) |
| || ((cpuid_edx & 1) == 0) |
| || ((amd_p || hygon_p) && (cpuid_edx & (3 << 30)) != 0)) |
| { |
| gdb_puts ("CPU Features..................."); |
| /* We only list features which might be useful in the DPMI |
| environment. */ |
| if ((cpuid_edx & 1) == 0) |
| gdb_puts ("No FPU "); /* It's unusual to not have an FPU. */ |
| if ((cpuid_edx & (1 << 1)) != 0) |
| gdb_puts ("VME "); |
| if ((cpuid_edx & (1 << 2)) != 0) |
| gdb_puts ("DE "); |
| if ((cpuid_edx & (1 << 4)) != 0) |
| gdb_puts ("TSC "); |
| if ((cpuid_edx & (1 << 23)) != 0) |
| gdb_puts ("MMX "); |
| if ((cpuid_edx & (1 << 25)) != 0) |
| gdb_puts ("SSE "); |
| if ((cpuid_edx & (1 << 26)) != 0) |
| gdb_puts ("SSE2 "); |
| if (amd_p || hygon_p) |
| { |
| if ((cpuid_edx & (1 << 31)) != 0) |
| gdb_puts ("3DNow! "); |
| if ((cpuid_edx & (1 << 30)) != 0) |
| gdb_puts ("3DNow!Ext"); |
| } |
| gdb_puts ("\n"); |
| } |
| } |
| gdb_puts ("\n"); |
| gdb_printf ("DOS Version....................%s %s.%s", |
| _os_flavor, u.release, u.version); |
| if (true_dos_version != advertized_dos_version) |
| gdb_printf (" (disguised as v%d.%d)", _osmajor, _osminor); |
| gdb_puts ("\n"); |
| if (!windows_major) |
| go32_get_windows_version (); |
| if (windows_major != 0xff) |
| { |
| const char *windows_flavor; |
| |
| gdb_printf ("Windows Version................%d.%02d (Windows ", |
| windows_major, windows_minor); |
| switch (windows_major) |
| { |
| case 3: |
| windows_flavor = "3.X"; |
| break; |
| case 4: |
| switch (windows_minor) |
| { |
| case 0: |
| windows_flavor = "95, 95A, or 95B"; |
| break; |
| case 3: |
| windows_flavor = "95B OSR2.1 or 95C OSR2.5"; |
| break; |
| case 10: |
| windows_flavor = "98 or 98 SE"; |
| break; |
| case 90: |
| windows_flavor = "ME"; |
| break; |
| default: |
| windows_flavor = "9X"; |
| break; |
| } |
| break; |
| default: |
| windows_flavor = "??"; |
| break; |
| } |
| gdb_printf ("%s)\n", windows_flavor); |
| } |
| else if (true_dos_version == 0x532 && advertized_dos_version == 0x500) |
| gdb_printf ("Windows Version................" |
| "Windows NT family (W2K/XP/W2K3/Vista/W2K8)\n"); |
| gdb_puts ("\n"); |
| /* On some versions of Windows, __dpmi_get_capabilities returns |
| zero, but the buffer is not filled with info, so we fill the |
| buffer with a known pattern and test for it afterwards. */ |
| memcpy (dpmi_vendor_info, test_pattern, sizeof(dpmi_vendor_info)); |
| dpmi_vendor_available = |
| __dpmi_get_capabilities (&dpmi_flags, dpmi_vendor_info); |
| if (dpmi_vendor_available == 0 |
| && memcmp (dpmi_vendor_info, test_pattern, |
| sizeof(dpmi_vendor_info)) != 0) |
| { |
| /* The DPMI spec says the vendor string should be ASCIIZ, but |
| I don't trust the vendors to follow that... */ |
| if (!memchr (&dpmi_vendor_info[2], 0, 126)) |
| dpmi_vendor_info[128] = '\0'; |
| gdb_printf ("DPMI Host......................" |
| "%s v%d.%d (capabilities: %#x)\n", |
| &dpmi_vendor_info[2], |
| (unsigned)dpmi_vendor_info[0], |
| (unsigned)dpmi_vendor_info[1], |
| ((unsigned)dpmi_flags & 0x7f)); |
| } |
| else |
| gdb_printf ("DPMI Host......................(Info not available)\n"); |
| __dpmi_get_version (&dpmi_version_data); |
| gdb_printf ("DPMI Version...................%d.%02d\n", |
| dpmi_version_data.major, dpmi_version_data.minor); |
| gdb_printf ("DPMI Info......................" |
| "%s-bit DPMI, with%s Virtual Memory support\n", |
| (dpmi_version_data.flags & 1) ? "32" : "16", |
| (dpmi_version_data.flags & 4) ? "" : "out"); |
| gdb_printf ("%*sInterrupts reflected to %s mode\n", 31, "", |
| (dpmi_version_data.flags & 2) ? "V86" : "Real"); |
| gdb_printf ("%*sProcessor type: i%d86\n", 31, "", |
| dpmi_version_data.cpu); |
| gdb_printf ("%*sPIC base interrupt: Master: %#x Slave: %#x\n", 31, "", |
| dpmi_version_data.master_pic, dpmi_version_data.slave_pic); |
| |
| /* a_tss is only initialized when the debuggee is first run. */ |
| if (prog_has_started) |
| { |
| __asm__ __volatile__ ("pushfl ; popl %0" : "=g" (eflags)); |
| gdb_printf ("Protection....................." |
| "Ring %d (in %s), with%s I/O protection\n", |
| a_tss.tss_cs & 3, (a_tss.tss_cs & 4) ? "LDT" : "GDT", |
| (a_tss.tss_cs & 3) > ((eflags >> 12) & 3) ? "" : "out"); |
| } |
| gdb_puts ("\n"); |
| __dpmi_get_free_memory_information (&mem_info); |
| print_mem (mem_info.total_number_of_physical_pages, |
| "DPMI Total Physical Memory.....", 1); |
| print_mem (mem_info.total_number_of_free_pages, |
| "DPMI Free Physical Memory......", 1); |
| print_mem (mem_info.size_of_paging_file_partition_in_pages, |
| "DPMI Swap Space................", 1); |
| print_mem (mem_info.linear_address_space_size_in_pages, |
| "DPMI Total Linear Address Size.", 1); |
| print_mem (mem_info.free_linear_address_space_in_pages, |
| "DPMI Free Linear Address Size..", 1); |
| print_mem (mem_info.largest_available_free_block_in_bytes, |
| "DPMI Largest Free Memory Block.", 0); |
| |
| regs.h.ah = 0x48; |
| regs.x.bx = 0xffff; |
| __dpmi_int (0x21, ®s); |
| print_mem (regs.x.bx << 4, "Free DOS Memory................", 0); |
| regs.x.ax = 0x5800; |
| __dpmi_int (0x21, ®s); |
| if ((regs.x.flags & 1) == 0) |
| { |
| static const char *dos_hilo[] = { |
| "Low", "", "", "", "High", "", "", "", "High, then Low" |
| }; |
| static const char *dos_fit[] = { |
| "First", "Best", "Last" |
| }; |
| int hilo_idx = (regs.x.ax >> 4) & 0x0f; |
| int fit_idx = regs.x.ax & 0x0f; |
| |
| if (hilo_idx > 8) |
| hilo_idx = 0; |
| if (fit_idx > 2) |
| fit_idx = 0; |
| gdb_printf ("DOS Memory Allocation..........%s memory, %s fit\n", |
| dos_hilo[hilo_idx], dos_fit[fit_idx]); |
| regs.x.ax = 0x5802; |
| __dpmi_int (0x21, ®s); |
| if ((regs.x.flags & 1) != 0) |
| regs.h.al = 0; |
| gdb_printf ("%*sUMBs %sin DOS memory chain\n", 31, "", |
| regs.h.al == 0 ? "not " : ""); |
| } |
| } |
| |
| struct seg_descr { |
| unsigned short limit0; |
| unsigned short base0; |
| unsigned char base1; |
| unsigned stype:5; |
| unsigned dpl:2; |
| unsigned present:1; |
| unsigned limit1:4; |
| unsigned available:1; |
| unsigned dummy:1; |
| unsigned bit32:1; |
| unsigned page_granular:1; |
| unsigned char base2; |
| } __attribute__ ((packed)); |
| |
| struct gate_descr { |
| unsigned short offset0; |
| unsigned short selector; |
| unsigned param_count:5; |
| unsigned dummy:3; |
| unsigned stype:5; |
| unsigned dpl:2; |
| unsigned present:1; |
| unsigned short offset1; |
| } __attribute__ ((packed)); |
| |
| /* Read LEN bytes starting at logical address ADDR, and put the result |
| into DEST. Return 1 if success, zero if not. */ |
| static int |
| read_memory_region (unsigned long addr, void *dest, size_t len) |
| { |
| unsigned long dos_ds_limit = __dpmi_get_segment_limit (_dos_ds); |
| int retval = 1; |
| |
| /* For the low memory, we can simply use _dos_ds. */ |
| if (addr <= dos_ds_limit - len) |
| dosmemget (addr, len, dest); |
| else |
| { |
| /* For memory above 1MB we need to set up a special segment to |
| be able to access that memory. */ |
| int sel = __dpmi_allocate_ldt_descriptors (1); |
| |
| if (sel <= 0) |
| retval = 0; |
| else |
| { |
| int access_rights = __dpmi_get_descriptor_access_rights (sel); |
| size_t segment_limit = len - 1; |
| |
| /* Make sure the crucial bits in the descriptor access |
| rights are set correctly. Some DPMI providers might barf |
| if we set the segment limit to something that is not an |
| integral multiple of 4KB pages if the granularity bit is |
| not set to byte-granular, even though the DPMI spec says |
| it's the host's responsibility to set that bit correctly. */ |
| if (len > 1024 * 1024) |
| { |
| access_rights |= 0x8000; |
| /* Page-granular segments should have the low 12 bits of |
| the limit set. */ |
| segment_limit |= 0xfff; |
| } |
| else |
| access_rights &= ~0x8000; |
| |
| if (__dpmi_set_segment_base_address (sel, addr) != -1 |
| && __dpmi_set_descriptor_access_rights (sel, access_rights) != -1 |
| && __dpmi_set_segment_limit (sel, segment_limit) != -1 |
| /* W2K silently fails to set the segment limit, leaving |
| it at zero; this test avoids the resulting crash. */ |
| && __dpmi_get_segment_limit (sel) >= segment_limit) |
| movedata (sel, 0, _my_ds (), (unsigned)dest, len); |
| else |
| retval = 0; |
| |
| __dpmi_free_ldt_descriptor (sel); |
| } |
| } |
| return retval; |
| } |
| |
| /* Get a segment descriptor stored at index IDX in the descriptor |
| table whose base address is TABLE_BASE. Return the descriptor |
| type, or -1 if failure. */ |
| static int |
| get_descriptor (unsigned long table_base, int idx, void *descr) |
| { |
| unsigned long addr = table_base + idx * 8; /* 8 bytes per entry */ |
| |
| if (read_memory_region (addr, descr, 8)) |
| return (int)((struct seg_descr *)descr)->stype; |
| return -1; |
| } |
| |
| struct dtr_reg { |
| unsigned short limit __attribute__((packed)); |
| unsigned long base __attribute__((packed)); |
| }; |
| |
| /* Display a segment descriptor stored at index IDX in a descriptor |
| table whose type is TYPE and whose base address is BASE_ADDR. If |
| FORCE is non-zero, display even invalid descriptors. */ |
| static void |
| display_descriptor (unsigned type, unsigned long base_addr, int idx, int force) |
| { |
| struct seg_descr descr; |
| struct gate_descr gate; |
| |
| /* Get the descriptor from the table. */ |
| if (idx == 0 && type == 0) |
| gdb_puts ("0x000: null descriptor\n"); |
| else if (get_descriptor (base_addr, idx, &descr) != -1) |
| { |
| /* For each type of descriptor table, this has a bit set if the |
| corresponding type of selectors is valid in that table. */ |
| static unsigned allowed_descriptors[] = { |
| 0xffffdafeL, /* GDT */ |
| 0x0000c0e0L, /* IDT */ |
| 0xffffdafaL /* LDT */ |
| }; |
| |
| /* If the program hasn't started yet, assume the debuggee will |
| have the same CPL as the debugger. */ |
| int cpl = prog_has_started ? (a_tss.tss_cs & 3) : _my_cs () & 3; |
| unsigned long limit = (descr.limit1 << 16) | descr.limit0; |
| |
| if (descr.present |
| && (allowed_descriptors[type] & (1 << descr.stype)) != 0) |
| { |
| gdb_printf ("0x%03x: ", |
| type == 1 |
| ? idx : (idx * 8) | (type ? (cpl | 4) : 0)); |
| if (descr.page_granular) |
| limit = (limit << 12) | 0xfff; /* big segment: low 12 bit set */ |
| if (descr.stype == 1 || descr.stype == 2 || descr.stype == 3 |
| || descr.stype == 9 || descr.stype == 11 |
| || (descr.stype >= 16 && descr.stype < 32)) |
| gdb_printf ("base=0x%02x%02x%04x limit=0x%08lx", |
| descr.base2, descr.base1, descr.base0, limit); |
| |
| switch (descr.stype) |
| { |
| case 1: |
| case 3: |
| gdb_printf (" 16-bit TSS (task %sactive)", |
| descr.stype == 3 ? "" : "in"); |
| break; |
| case 2: |
| gdb_puts (" LDT"); |
| break; |
| case 4: |
| memcpy (&gate, &descr, sizeof gate); |
| gdb_printf ("selector=0x%04x offs=0x%04x%04x", |
| gate.selector, gate.offset1, gate.offset0); |
| gdb_printf (" 16-bit Call Gate (params=%d)", |
| gate.param_count); |
| break; |
| case 5: |
| gdb_printf ("TSS selector=0x%04x", descr.base0); |
| gdb_printf ("%*sTask Gate", 16, ""); |
| break; |
| case 6: |
| case 7: |
| memcpy (&gate, &descr, sizeof gate); |
| gdb_printf ("selector=0x%04x offs=0x%04x%04x", |
| gate.selector, gate.offset1, gate.offset0); |
| gdb_printf (" 16-bit %s Gate", |
| descr.stype == 6 ? "Interrupt" : "Trap"); |
| break; |
| case 9: |
| case 11: |
| gdb_printf (" 32-bit TSS (task %sactive)", |
| descr.stype == 3 ? "" : "in"); |
| break; |
| case 12: |
| memcpy (&gate, &descr, sizeof gate); |
| gdb_printf ("selector=0x%04x offs=0x%04x%04x", |
| gate.selector, gate.offset1, gate.offset0); |
| gdb_printf (" 32-bit Call Gate (params=%d)", |
| gate.param_count); |
| break; |
| case 14: |
| case 15: |
| memcpy (&gate, &descr, sizeof gate); |
| gdb_printf ("selector=0x%04x offs=0x%04x%04x", |
| gate.selector, gate.offset1, gate.offset0); |
| gdb_printf (" 32-bit %s Gate", |
| descr.stype == 14 ? "Interrupt" : "Trap"); |
| break; |
| case 16: /* data segments */ |
| case 17: |
| case 18: |
| case 19: |
| case 20: |
| case 21: |
| case 22: |
| case 23: |
| gdb_printf (" %s-bit Data (%s Exp-%s%s)", |
| descr.bit32 ? "32" : "16", |
| descr.stype & 2 |
| ? "Read/Write," : "Read-Only, ", |
| descr.stype & 4 ? "down" : "up", |
| descr.stype & 1 ? "" : ", N.Acc"); |
| break; |
| case 24: /* code segments */ |
| case 25: |
| case 26: |
| case 27: |
| case 28: |
| case 29: |
| case 30: |
| case 31: |
| gdb_printf (" %s-bit Code (%s, %sConf%s)", |
| descr.bit32 ? "32" : "16", |
| descr.stype & 2 ? "Exec/Read" : "Exec-Only", |
| descr.stype & 4 ? "" : "N.", |
| descr.stype & 1 ? "" : ", N.Acc"); |
| break; |
| default: |
| gdb_printf ("Unknown type 0x%02x", descr.stype); |
| break; |
| } |
| gdb_puts ("\n"); |
| } |
| else if (force) |
| { |
| gdb_printf ("0x%03x: ", |
| type == 1 |
| ? idx : (idx * 8) | (type ? (cpl | 4) : 0)); |
| if (!descr.present) |
| gdb_puts ("Segment not present\n"); |
| else |
| gdb_printf ("Segment type 0x%02x is invalid in this table\n", |
| descr.stype); |
| } |
| } |
| else if (force) |
| gdb_printf ("0x%03x: Cannot read this descriptor\n", idx); |
| } |
| |
| static void |
| go32_sldt (const char *arg, int from_tty) |
| { |
| struct dtr_reg gdtr; |
| unsigned short ldtr = 0; |
| int ldt_idx; |
| struct seg_descr ldt_descr; |
| long ldt_entry = -1L; |
| int cpl = (prog_has_started ? a_tss.tss_cs : _my_cs ()) & 3; |
| |
| if (arg && *arg) |
| { |
| arg = skip_spaces (arg); |
| |
| if (*arg) |
| { |
| ldt_entry = parse_and_eval_long (arg); |
| if (ldt_entry < 0 |
| || (ldt_entry & 4) == 0 |
| || (ldt_entry & 3) != (cpl & 3)) |
| error (_("Invalid LDT entry 0x%03lx."), (unsigned long)ldt_entry); |
| } |
| } |
| |
| __asm__ __volatile__ ("sgdt %0" : "=m" (gdtr) : /* no inputs */ ); |
| __asm__ __volatile__ ("sldt %0" : "=m" (ldtr) : /* no inputs */ ); |
| ldt_idx = ldtr / 8; |
| if (ldt_idx == 0) |
| gdb_puts ("There is no LDT.\n"); |
| /* LDT's entry in the GDT must have the type LDT, which is 2. */ |
| else if (get_descriptor (gdtr.base, ldt_idx, &ldt_descr) != 2) |
| gdb_printf ("LDT is present (at %#x), but unreadable by GDB.\n", |
| ldt_descr.base0 |
| | (ldt_descr.base1 << 16) |
| | (ldt_descr.base2 << 24)); |
| else |
| { |
| unsigned base = |
| ldt_descr.base0 |
| | (ldt_descr.base1 << 16) |
| | (ldt_descr.base2 << 24); |
| unsigned limit = ldt_descr.limit0 | (ldt_descr.limit1 << 16); |
| int max_entry; |
| |
| if (ldt_descr.page_granular) |
| /* Page-granular segments must have the low 12 bits of their |
| limit set. */ |
| limit = (limit << 12) | 0xfff; |
| /* LDT cannot have more than 8K 8-byte entries, i.e. more than |
| 64KB. */ |
| if (limit > 0xffff) |
| limit = 0xffff; |
| |
| max_entry = (limit + 1) / 8; |
| |
| if (ldt_entry >= 0) |
| { |
| if (ldt_entry > limit) |
| error (_("Invalid LDT entry %#lx: outside valid limits [0..%#x]"), |
| (unsigned long)ldt_entry, limit); |
| |
| display_descriptor (ldt_descr.stype, base, ldt_entry / 8, 1); |
| } |
| else |
| { |
| int i; |
| |
| for (i = 0; i < max_entry; i++) |
| display_descriptor (ldt_descr.stype, base, i, 0); |
| } |
| } |
| } |
| |
| static void |
| go32_sgdt (const char *arg, int from_tty) |
| { |
| struct dtr_reg gdtr; |
| long gdt_entry = -1L; |
| int max_entry; |
| |
| if (arg && *arg) |
| { |
| arg = skip_spaces (arg); |
| |
| if (*arg) |
| { |
| gdt_entry = parse_and_eval_long (arg); |
| if (gdt_entry < 0 || (gdt_entry & 7) != 0) |
| error (_("Invalid GDT entry 0x%03lx: " |
| "not an integral multiple of 8."), |
| (unsigned long)gdt_entry); |
| } |
| } |
| |
| __asm__ __volatile__ ("sgdt %0" : "=m" (gdtr) : /* no inputs */ ); |
| max_entry = (gdtr.limit + 1) / 8; |
| |
| if (gdt_entry >= 0) |
| { |
| if (gdt_entry > gdtr.limit) |
| error (_("Invalid GDT entry %#lx: outside valid limits [0..%#x]"), |
| (unsigned long)gdt_entry, gdtr.limit); |
| |
| display_descriptor (0, gdtr.base, gdt_entry / 8, 1); |
| } |
| else |
| { |
| int i; |
| |
| for (i = 0; i < max_entry; i++) |
| display_descriptor (0, gdtr.base, i, 0); |
| } |
| } |
| |
| static void |
| go32_sidt (const char *arg, int from_tty) |
| { |
| struct dtr_reg idtr; |
| long idt_entry = -1L; |
| int max_entry; |
| |
| if (arg && *arg) |
| { |
| arg = skip_spaces (arg); |
| |
| if (*arg) |
| { |
| idt_entry = parse_and_eval_long (arg); |
| if (idt_entry < 0) |
| error (_("Invalid (negative) IDT entry %ld."), idt_entry); |
| } |
| } |
| |
| __asm__ __volatile__ ("sidt %0" : "=m" (idtr) : /* no inputs */ ); |
| max_entry = (idtr.limit + 1) / 8; |
| if (max_entry > 0x100) /* No more than 256 entries. */ |
| max_entry = 0x100; |
| |
| if (idt_entry >= 0) |
| { |
| if (idt_entry > idtr.limit) |
| error (_("Invalid IDT entry %#lx: outside valid limits [0..%#x]"), |
| (unsigned long)idt_entry, idtr.limit); |
| |
| display_descriptor (1, idtr.base, idt_entry, 1); |
| } |
| else |
| { |
| int i; |
| |
| for (i = 0; i < max_entry; i++) |
| display_descriptor (1, idtr.base, i, 0); |
| } |
| } |
| |
| /* Cached linear address of the base of the page directory. For |
| now, available only under CWSDPMI. Code based on ideas and |
| suggestions from Charles Sandmann <sandmann@clio.rice.edu>. */ |
| static unsigned long pdbr; |
| |
| static unsigned long |
| get_cr3 (void) |
| { |
| unsigned offset; |
| unsigned taskreg; |
| unsigned long taskbase, cr3; |
| struct dtr_reg gdtr; |
| |
| if (pdbr > 0 && pdbr <= 0xfffff) |
| return pdbr; |
| |
| /* Get the linear address of GDT and the Task Register. */ |
| __asm__ __volatile__ ("sgdt %0" : "=m" (gdtr) : /* no inputs */ ); |
| __asm__ __volatile__ ("str %0" : "=m" (taskreg) : /* no inputs */ ); |
| |
| /* Task Register is a segment selector for the TSS of the current |
| task. Therefore, it can be used as an index into the GDT to get |
| at the segment descriptor for the TSS. To get the index, reset |
| the low 3 bits of the selector (which give the CPL). Add 2 to the |
| offset to point to the 3 low bytes of the base address. */ |
| offset = gdtr.base + (taskreg & 0xfff8) + 2; |
| |
| |
| /* CWSDPMI's task base is always under the 1MB mark. */ |
| if (offset > 0xfffff) |
| return 0; |
| |
| _farsetsel (_dos_ds); |
| taskbase = _farnspeekl (offset) & 0xffffffU; |
| taskbase += _farnspeekl (offset + 2) & 0xff000000U; |
| if (taskbase > 0xfffff) |
| return 0; |
| |
| /* CR3 (a.k.a. PDBR, the Page Directory Base Register) is stored at |
| offset 1Ch in the TSS. */ |
| cr3 = _farnspeekl (taskbase + 0x1c) & ~0xfff; |
| if (cr3 > 0xfffff) |
| { |
| #if 0 /* Not fully supported yet. */ |
| /* The Page Directory is in UMBs. In that case, CWSDPMI puts |
| the first Page Table right below the Page Directory. Thus, |
| the first Page Table's entry for its own address and the Page |
| Directory entry for that Page Table will hold the same |
| physical address. The loop below searches the entire UMB |
| range of addresses for such an occurrence. */ |
| unsigned long addr, pte_idx; |
| |
| for (addr = 0xb0000, pte_idx = 0xb0; |
| pte_idx < 0xff; |
| addr += 0x1000, pte_idx++) |
| { |
| if (((_farnspeekl (addr + 4 * pte_idx) & 0xfffff027) == |
| (_farnspeekl (addr + 0x1000) & 0xfffff027)) |
| && ((_farnspeekl (addr + 4 * pte_idx + 4) & 0xfffff000) == cr3)) |
| { |
| cr3 = addr + 0x1000; |
| break; |
| } |
| } |
| #endif |
| |
| if (cr3 > 0xfffff) |
| cr3 = 0; |
| } |
| |
| return cr3; |
| } |
| |
| /* Return the N'th Page Directory entry. */ |
| static unsigned long |
| get_pde (int n) |
| { |
| unsigned long pde = 0; |
| |
| if (pdbr && n >= 0 && n < 1024) |
| { |
| pde = _farpeekl (_dos_ds, pdbr + 4*n); |
| } |
| return pde; |
| } |
| |
| /* Return the N'th entry of the Page Table whose Page Directory entry |
| is PDE. */ |
| static unsigned long |
| get_pte (unsigned long pde, int n) |
| { |
| unsigned long pte = 0; |
| |
| /* pde & 0x80 tests the 4MB page bit. We don't support 4MB |
| page tables, for now. */ |
| if ((pde & 1) && !(pde & 0x80) && n >= 0 && n < 1024) |
| { |
| pde &= ~0xfff; /* Clear non-address bits. */ |
| pte = _farpeekl (_dos_ds, pde + 4*n); |
| } |
| return pte; |
| } |
| |
| /* Display a Page Directory or Page Table entry. IS_DIR, if non-zero, |
| says this is a Page Directory entry. If FORCE is non-zero, display |
| the entry even if its Present flag is off. OFF is the offset of the |
| address from the page's base address. */ |
| static void |
| display_ptable_entry (unsigned long entry, int is_dir, int force, unsigned off) |
| { |
| if ((entry & 1) != 0) |
| { |
| gdb_printf ("Base=0x%05lx000", entry >> 12); |
| if ((entry & 0x100) && !is_dir) |
| gdb_puts (" Global"); |
| if ((entry & 0x40) && !is_dir) |
| gdb_puts (" Dirty"); |
| gdb_printf (" %sAcc.", (entry & 0x20) ? "" : "Not-"); |
| gdb_printf (" %sCached", (entry & 0x10) ? "" : "Not-"); |
| gdb_printf (" Write-%s", (entry & 8) ? "Thru" : "Back"); |
| gdb_printf (" %s", (entry & 4) ? "Usr" : "Sup"); |
| gdb_printf (" Read-%s", (entry & 2) ? "Write" : "Only"); |
| if (off) |
| gdb_printf (" +0x%x", off); |
| gdb_puts ("\n"); |
| } |
| else if (force) |
| gdb_printf ("Page%s not present or not supported; value=0x%lx.\n", |
| is_dir ? " Table" : "", entry >> 1); |
| } |
| |
| static void |
| go32_pde (const char *arg, int from_tty) |
| { |
| long pde_idx = -1, i; |
| |
| if (arg && *arg) |
| { |
| arg = skip_spaces (arg); |
| |
| if (*arg) |
| { |
| pde_idx = parse_and_eval_long (arg); |
| if (pde_idx < 0 || pde_idx >= 1024) |
| error (_("Entry %ld is outside valid limits [0..1023]."), pde_idx); |
| } |
| } |
| |
| pdbr = get_cr3 (); |
| if (!pdbr) |
| gdb_puts ("Access to Page Directories is " |
| "not supported on this system.\n"); |
| else if (pde_idx >= 0) |
| display_ptable_entry (get_pde (pde_idx), 1, 1, 0); |
| else |
| for (i = 0; i < 1024; i++) |
| display_ptable_entry (get_pde (i), 1, 0, 0); |
| } |
| |
| /* A helper function to display entries in a Page Table pointed to by |
| the N'th entry in the Page Directory. If FORCE is non-zero, say |
| something even if the Page Table is not accessible. */ |
| static void |
| display_page_table (long n, int force) |
| { |
| unsigned long pde = get_pde (n); |
| |
| if ((pde & 1) != 0) |
| { |
| int i; |
| |
| gdb_printf ("Page Table pointed to by " |
| "Page Directory entry 0x%lx:\n", n); |
| for (i = 0; i < 1024; i++) |
| display_ptable_entry (get_pte (pde, i), 0, 0, 0); |
| gdb_puts ("\n"); |
| } |
| else if (force) |
| gdb_printf ("Page Table not present; value=0x%lx.\n", pde >> 1); |
| } |
| |
| static void |
| go32_pte (const char *arg, int from_tty) |
| { |
| long pde_idx = -1L, i; |
| |
| if (arg && *arg) |
| { |
| arg = skip_spaces (arg); |
| |
| if (*arg) |
| { |
| pde_idx = parse_and_eval_long (arg); |
| if (pde_idx < 0 || pde_idx >= 1024) |
| error (_("Entry %ld is outside valid limits [0..1023]."), pde_idx); |
| } |
| } |
| |
| pdbr = get_cr3 (); |
| if (!pdbr) |
| gdb_puts ("Access to Page Tables is not supported on this system.\n"); |
| else if (pde_idx >= 0) |
| display_page_table (pde_idx, 1); |
| else |
| for (i = 0; i < 1024; i++) |
| display_page_table (i, 0); |
| } |
| |
| static void |
| go32_pte_for_address (const char *arg, int from_tty) |
| { |
| CORE_ADDR addr = 0, i; |
| |
| if (arg && *arg) |
| { |
| arg = skip_spaces (arg); |
| |
| if (*arg) |
| addr = parse_and_eval_address (arg); |
| } |
| if (!addr) |
| error_no_arg (_("linear address")); |
| |
| pdbr = get_cr3 (); |
| if (!pdbr) |
| gdb_puts ("Access to Page Tables is not supported on this system.\n"); |
| else |
| { |
| int pde_idx = (addr >> 22) & 0x3ff; |
| int pte_idx = (addr >> 12) & 0x3ff; |
| unsigned offs = addr & 0xfff; |
| |
| gdb_printf ("Page Table entry for address %s:\n", |
| hex_string(addr)); |
| display_ptable_entry (get_pte (get_pde (pde_idx), pte_idx), 0, 1, offs); |
| } |
| } |
| |
| static struct cmd_list_element *info_dos_cmdlist = NULL; |
| |
| void _initialize_go32_nat (); |
| void |
| _initialize_go32_nat () |
| { |
| x86_dr_low.set_control = go32_set_dr7; |
| x86_dr_low.set_addr = go32_set_dr; |
| x86_dr_low.get_status = go32_get_dr6; |
| x86_dr_low.get_control = go32_get_dr7; |
| x86_dr_low.get_addr = go32_get_dr; |
| x86_set_debug_register_length (4); |
| |
| add_inf_child_target (&the_go32_nat_target); |
| |
| /* Initialize child's cwd as empty to be initialized when starting |
| the child. */ |
| *child_cwd = 0; |
| |
| /* Initialize child's command line storage. */ |
| if (redir_debug_init (&child_cmd) == -1) |
| internal_error (_("Cannot allocate redirection storage: " |
| "not enough memory.\n")); |
| |
| /* We are always processing GCC-compiled programs. */ |
| processing_gcc_compilation = 2; |
| |
| add_basic_prefix_cmd ("dos", class_info, _("\ |
| Print information specific to DJGPP (aka MS-DOS) debugging."), |
| &info_dos_cmdlist, 0, &infolist); |
| |
| add_cmd ("sysinfo", class_info, go32_sysinfo, _("\ |
| Display information about the target system, including CPU, OS, DPMI, etc."), |
| &info_dos_cmdlist); |
| add_cmd ("ldt", class_info, go32_sldt, _("\ |
| Display entries in the LDT (Local Descriptor Table).\n\ |
| Entry number (an expression) as an argument means display only that entry."), |
| &info_dos_cmdlist); |
| add_cmd ("gdt", class_info, go32_sgdt, _("\ |
| Display entries in the GDT (Global Descriptor Table).\n\ |
| Entry number (an expression) as an argument means display only that entry."), |
| &info_dos_cmdlist); |
| add_cmd ("idt", class_info, go32_sidt, _("\ |
| Display entries in the IDT (Interrupt Descriptor Table).\n\ |
| Entry number (an expression) as an argument means display only that entry."), |
| &info_dos_cmdlist); |
| add_cmd ("pde", class_info, go32_pde, _("\ |
| Display entries in the Page Directory.\n\ |
| Entry number (an expression) as an argument means display only that entry."), |
| &info_dos_cmdlist); |
| add_cmd ("pte", class_info, go32_pte, _("\ |
| Display entries in Page Tables.\n\ |
| Entry number (an expression) as an argument means display only entries\n\ |
| from the Page Table pointed to by the specified Page Directory entry."), |
| &info_dos_cmdlist); |
| add_cmd ("address-pte", class_info, go32_pte_for_address, _("\ |
| Display a Page Table entry for a linear address.\n\ |
| The address argument must be a linear address, after adding to\n\ |
| it the base address of the appropriate segment.\n\ |
| The base address of variables and functions in the debuggee's data\n\ |
| or code segment is stored in the variable __djgpp_base_address,\n\ |
| so use `__djgpp_base_address + (char *)&var' as the argument.\n\ |
| For other segments, look up their base address in the output of\n\ |
| the `info dos ldt' command."), |
| &info_dos_cmdlist); |
| } |
| |
| pid_t |
| tcgetpgrp (int fd) |
| { |
| if (isatty (fd)) |
| return SOME_PID; |
| errno = ENOTTY; |
| return -1; |
| } |
| |
| int |
| tcsetpgrp (int fd, pid_t pgid) |
| { |
| if (isatty (fd) && pgid == SOME_PID) |
| return 0; |
| errno = pgid == SOME_PID ? ENOTTY : ENOSYS; |
| return -1; |
| } |