aboutsummaryrefslogtreecommitdiff
path: root/gdb/standalone.c
diff options
context:
space:
mode:
Diffstat (limited to 'gdb/standalone.c')
-rw-r--r--gdb/standalone.c593
1 files changed, 593 insertions, 0 deletions
diff --git a/gdb/standalone.c b/gdb/standalone.c
new file mode 100644
index 0000000..13fc476
--- /dev/null
+++ b/gdb/standalone.c
@@ -0,0 +1,593 @@
+/* Interface to bare machine for GDB running as kernel debugger.
+ Copyright (C) 1986, 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 <stdio.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <sys/types.h>
+#include "gdb_stat.h"
+
+#if defined (SIGTSTP) && defined (SIGIO)
+#include <sys/time.h>
+#include <sys/resource.h>
+#endif /* SIGTSTP and SIGIO defined (must be 4.2) */
+
+#include "defs.h"
+#include "signals.h"
+#include "symtab.h"
+#include "frame.h"
+#include "inferior.h"
+#include "wait.h"
+
+
+/* Random system calls, mostly no-ops to prevent link problems */
+
+ioctl (desc, code, arg)
+{}
+
+int (* signal ()) ()
+{}
+
+kill ()
+{}
+
+getpid ()
+{
+ return 0;
+}
+
+sigsetmask ()
+{}
+
+chdir ()
+{}
+
+char *
+getcwd (buf, len)
+ char *buf;
+ unsigned int len;
+{
+ buf[0] = '/';
+ buf[1] = 0;
+ return buf;
+}
+
+/* Used to check for existence of .gdbinit. Say no. */
+
+access ()
+{
+ return -1;
+}
+
+exit ()
+{
+ error ("Fatal error; restarting.");
+}
+
+/* Reading "files". The contents of some files are written into kdb's
+ data area before it is run. These files are used to contain the
+ symbol table for kdb to load, and the source files (in case the
+ kdb user wants to print them). The symbols are stored in a file
+ named "kdb-symbols" in a.out format (except that all the text and
+ data have been stripped to save room).
+
+ The files are stored in the following format:
+ int number of bytes of data for this file, including these four.
+ char[] name of the file, ending with a null.
+ padding to multiple of 4 boundary.
+ char[] file contents. The length can be deduced from what was
+ specified before. There is no terminating null here.
+
+ If the int at the front is zero, it means there are no more files.
+
+ Opening a file in kdb returns a nonzero value to indicate success,
+ but the value does not matter. Only one file can be open, and only
+ for reading. All the primitives for input from the file know
+ which file is open and ignore what is specified for the descriptor
+ or for the stdio stream.
+
+ Input with fgetc can be done either on the file that is open
+ or on stdin (which reads from the terminal through tty_input () */
+
+/* Address of data for the files stored in format described above. */
+char *files_start;
+
+/* The file stream currently open: */
+
+char *sourcebeg; /* beginning of contents */
+int sourcesize; /* size of contents */
+char *sourceptr; /* current read pointer */
+int sourceleft; /* number of bytes to eof */
+
+/* "descriptor" for the file now open.
+ Incremented at each close.
+ If specified descriptor does not match this,
+ it means the program is trying to use a closed descriptor.
+ We report an error for that. */
+
+int sourcedesc;
+
+open (filename, modes)
+ char *filename;
+ int modes;
+{
+ register char *next;
+
+ if (modes)
+ {
+ errno = EROFS;
+ return -1;
+ }
+
+ if (sourceptr)
+ {
+ errno = EMFILE;
+ return -1;
+ }
+
+ for (next = files_start; * (int *) next; next += * (int *) next)
+ {
+ if (!STRCMP (next + 4, filename))
+ {
+ sourcebeg = next + 4 + strlen (next + 4) + 1;
+ sourcebeg = (char *) (((int) sourcebeg + 3) & (-4));
+ sourceptr = sourcebeg;
+ sourcesize = next + * (int *) next - sourceptr;
+ sourceleft = sourcesize;
+ return sourcedesc;
+ }
+ }
+ return 0;
+}
+
+close (desc)
+ int desc;
+{
+ sourceptr = 0;
+ sourcedesc++;
+ /* Don't let sourcedesc get big enough to be confused with stdin. */
+ if (sourcedesc == 100)
+ sourcedesc = 5;
+}
+
+FILE *
+fopen (filename, modes)
+ char *filename;
+ char *modes;
+{
+ return (FILE *) open (filename, *modes == 'w');
+}
+
+FILE *
+fdopen (desc)
+ int desc;
+{
+ return (FILE *) desc;
+}
+
+fclose (desc)
+ int desc;
+{
+ close (desc);
+}
+
+fstat (desc, statbuf)
+ struct stat *statbuf;
+{
+ if (desc != sourcedesc)
+ {
+ errno = EBADF;
+ return -1;
+ }
+ statbuf->st_size = sourcesize;
+}
+
+myread (desc, destptr, size, filename)
+ int desc;
+ char *destptr;
+ int size;
+ char *filename;
+{
+ int len = min (sourceleft, size);
+
+ if (desc != sourcedesc)
+ {
+ errno = EBADF;
+ return -1;
+ }
+
+ memcpy (destptr, sourceptr, len);
+ sourceleft -= len;
+ return len;
+}
+
+int
+fread (bufp, numelts, eltsize, stream)
+{
+ register int elts = min (numelts, sourceleft / eltsize);
+ register int len = elts * eltsize;
+
+ if (stream != sourcedesc)
+ {
+ errno = EBADF;
+ return -1;
+ }
+
+ memcpy (bufp, sourceptr, len);
+ sourceleft -= len;
+ return elts;
+}
+
+int
+fgetc (desc)
+ int desc;
+{
+
+ if (desc == (int) stdin)
+ return tty_input ();
+
+ if (desc != sourcedesc)
+ {
+ errno = EBADF;
+ return -1;
+ }
+
+ if (sourceleft-- <= 0)
+ return EOF;
+ return *sourceptr++;
+}
+
+lseek (desc, pos)
+ int desc;
+ int pos;
+{
+
+ if (desc != sourcedesc)
+ {
+ errno = EBADF;
+ return -1;
+ }
+
+ if (pos < 0 || pos > sourcesize)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ sourceptr = sourcebeg + pos;
+ sourceleft = sourcesize - pos;
+}
+
+/* Output in kdb can go only to the terminal, so the stream
+ specified may be ignored. */
+
+printf (a1, a2, a3, a4, a5, a6, a7, a8, a9)
+{
+ char buffer[1024];
+ sprintf (buffer, a1, a2, a3, a4, a5, a6, a7, a8, a9);
+ display_string (buffer);
+}
+
+fprintf (ign, a1, a2, a3, a4, a5, a6, a7, a8, a9)
+{
+ char buffer[1024];
+ sprintf (buffer, a1, a2, a3, a4, a5, a6, a7, a8, a9);
+ display_string (buffer);
+}
+
+fwrite (buf, numelts, size, stream)
+ register char *buf;
+ int numelts, size;
+{
+ register int i = numelts * size;
+ while (i-- > 0)
+ fputc (*buf++, stream);
+}
+
+fputc (c, ign)
+{
+ char buf[2];
+ buf[0] = c;
+ buf[1] = 0;
+ display_string (buf);
+}
+
+/* sprintf refers to this, but loading this from the
+ library would cause fflush to be loaded from it too.
+ In fact there should be no need to call this (I hope). */
+
+_flsbuf ()
+{
+ error ("_flsbuf was actually called.");
+}
+
+fflush (ign)
+{
+}
+
+/* Entries into core and inflow, needed only to make things link ok. */
+
+exec_file_command ()
+{}
+
+core_file_command ()
+{}
+
+char *
+get_exec_file (err)
+ int err;
+{
+ /* Makes one printout look reasonable; value does not matter otherwise. */
+ return "run";
+}
+
+/* Nonzero if there is a core file. */
+
+have_core_file_p ()
+{
+ return 0;
+}
+
+kill_command ()
+{
+ inferior_pid = 0;
+}
+
+terminal_inferior ()
+{}
+
+terminal_ours ()
+{}
+
+terminal_init_inferior ()
+{}
+
+write_inferior_register ()
+{}
+
+read_inferior_register ()
+{}
+
+read_memory (memaddr, myaddr, len)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+{
+ memcpy (myaddr, memaddr, len);
+}
+
+/* Always return 0 indicating success. */
+
+write_memory (memaddr, myaddr, len)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+{
+ memcpy (memaddr, myaddr, len);
+ return 0;
+}
+
+static REGISTER_TYPE saved_regs[NUM_REGS];
+
+REGISTER_TYPE
+read_register (regno)
+ int regno;
+{
+ if (regno < 0 || regno >= NUM_REGS)
+ error ("Register number %d out of range.", regno);
+ return saved_regs[regno];
+}
+
+void
+write_register (regno, value)
+ int regno;
+ REGISTER_TYPE value;
+{
+ if (regno < 0 || regno >= NUM_REGS)
+ error ("Register number %d out of range.", regno);
+ saved_regs[regno] = value;
+}
+
+/* System calls needed in relation to running the "inferior". */
+
+vfork ()
+{
+ /* Just appear to "succeed". Say the inferior's pid is 1. */
+ return 1;
+}
+
+/* These are called by code that normally runs in the inferior
+ that has just been forked. That code never runs, when standalone,
+ and these definitions are so it will link without errors. */
+
+ptrace ()
+{}
+
+setpgrp ()
+{}
+
+execle ()
+{}
+
+_exit ()
+{}
+
+/* Malloc calls these. */
+
+malloc_warning (str)
+ char *str;
+{
+ printf ("\n%s.\n\n", str);
+}
+
+char *next_free;
+char *memory_limit;
+
+char *
+sbrk (amount)
+ int amount;
+{
+ if (next_free + amount > memory_limit)
+ return (char *) -1;
+ next_free += amount;
+ return next_free - amount;
+}
+
+/* Various ways malloc might ask where end of memory is. */
+
+char *
+ulimit ()
+{
+ return memory_limit;
+}
+
+int
+vlimit ()
+{
+ return memory_limit - next_free;
+}
+
+getrlimit (addr)
+ struct rlimit *addr;
+{
+ addr->rlim_cur = memory_limit - next_free;
+}
+
+/* Context switching to and from program being debugged. */
+
+/* GDB calls here to run the user program.
+ The frame pointer for this function is saved in
+ gdb_stack by save_frame_pointer; then we restore
+ all of the user program's registers, including PC and PS. */
+
+static int fault_code;
+static REGISTER_TYPE gdb_stack;
+
+resume ()
+{
+ REGISTER_TYPE restore[NUM_REGS];
+
+ PUSH_FRAME_PTR;
+ save_frame_pointer ();
+
+ memcpy (restore, saved_regs, sizeof restore);
+ POP_REGISTERS;
+ /* Control does not drop through here! */
+}
+
+save_frame_pointer (val)
+ CORE_ADDR val;
+{
+ gdb_stack = val;
+}
+
+/* Fault handlers call here, running in the user program stack.
+ They must first push a fault code,
+ old PC, old PS, and any other info about the fault.
+ The exact format is machine-dependent and is known only
+ in the definition of PUSH_REGISTERS. */
+
+fault ()
+{
+ /* Transfer all registers and fault code to the stack
+ in canonical order: registers in order of GDB register number,
+ followed by fault code. */
+ PUSH_REGISTERS;
+
+ /* Transfer them to saved_regs and fault_code. */
+ save_registers ();
+
+ restore_gdb ();
+ /* Control does not reach here */
+}
+
+restore_gdb ()
+{
+ CORE_ADDR new_fp = gdb_stack;
+ /* Switch to GDB's stack */
+ POP_FRAME_PTR;
+ /* Return from the function `resume'. */
+}
+
+/* Assuming register contents and fault code have been pushed on the stack as
+ arguments to this function, copy them into the standard place
+ for the program's registers while GDB is running. */
+
+save_registers (firstreg)
+ int firstreg;
+{
+ memcpy (saved_regs, &firstreg, sizeof saved_regs);
+ fault_code = (&firstreg)[NUM_REGS];
+}
+
+/* Store into the structure such as `wait' would return
+ the information on why the program faulted,
+ converted into a machine-independent signal number. */
+
+static int fault_table[] = FAULT_TABLE;
+
+int
+wait (w)
+ WAITTYPE *w;
+{
+ WSETSTOP (*w, fault_table[fault_code / FAULT_CODE_UNITS]);
+ return inferior_pid;
+}
+
+/* Allocate a big space in which files for kdb to read will be stored.
+ Whatever is left is where malloc can allocate storage.
+
+ Initialize it, so that there will be space in the executable file
+ for it. Then the files can be put into kdb by writing them into
+ kdb's executable file. */
+
+/* The default size is as much space as we expect to be available
+ for kdb to use! */
+
+#ifndef HEAP_SIZE
+#define HEAP_SIZE 400000
+#endif
+
+char heap[HEAP_SIZE] = {0};
+
+#ifndef STACK_SIZE
+#define STACK_SIZE 100000
+#endif
+
+int kdb_stack_beg[STACK_SIZE / sizeof (int)];
+int kdb_stack_end;
+
+_initialize_standalone ()
+{
+ register char *next;
+
+ /* Find start of data on files. */
+
+ files_start = heap;
+
+ /* Find the end of the data on files. */
+
+ for (next = files_start; * (int *) next; next += * (int *) next) {}
+
+ /* That is where free storage starts for sbrk to give out. */
+ next_free = next;
+
+ memory_limit = heap + sizeof heap;
+}
+
generated by cgit v1.1 at 2024-11-27 21:24:21 +0000