tui-io.c

这个是LINUX下的GDB调度工具的源码

/* TUI support I/O functions.

   Copyright 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software
   Foundation, Inc.

   Contributed by Hewlett-Packard Company.

   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 "terminal.h"
#include "target.h"
#include "event-loop.h"
#include "event-top.h"
#include "command.h"
#include "top.h"
#include "tui/tui.h"
#include "tui/tui-data.h"
#include "tui/tui-io.h"
#include "tui/tui-command.h"
#include "tui/tui-win.h"
#include "tui/tui-wingeneral.h"
#include "tui/tui-file.h"
#include "ui-out.h"
#include "cli-out.h"
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>

#include "gdb_curses.h"

/* This redefines CTRL if it is not already defined, so it must come
   after terminal state releated include files like <term.h> and
   "gdb_curses.h".  */
#include "readline/readline.h"

int
key_is_start_sequence (int ch)
{
  return (ch == 27);
}

int
key_is_end_sequence (int ch)
{
  return (ch == 126);
}

int
key_is_backspace (int ch)
{
  return (ch == 8);
}

int
key_is_command_char (int ch)
{
  return ((ch == KEY_NPAGE) || (ch == KEY_PPAGE)
	  || (ch == KEY_LEFT) || (ch == KEY_RIGHT)
	  || (ch == KEY_UP) || (ch == KEY_DOWN)
	  || (ch == KEY_SF) || (ch == KEY_SR)
	  || (ch == (int)'\f') || key_is_start_sequence (ch));
}

/* Use definition from readline 4.3.  */
#undef CTRL_CHAR
#define CTRL_CHAR(c) ((c) < control_character_threshold && (((c) & 0x80) == 0))

/* This file controls the IO interactions between gdb and curses.
   When the TUI is enabled, gdb has two modes a curses and a standard
   mode.

   In curses mode, the gdb outputs are made in a curses command window.
   For this, the gdb_stdout and gdb_stderr are redirected to the specific
   ui_file implemented by TUI.  The output is handled by tui_puts().
   The input is also controlled by curses with tui_getc().  The readline
   library uses this function to get its input.  Several readline hooks
   are installed to redirect readline output to the TUI (see also the
   note below).

   In normal mode, the gdb outputs are restored to their origin, that
   is as if TUI is not used.  Readline also uses its original getc()
   function with stdin.

   Note SCz/2001-07-21: the current readline is not clean in its management of
   the output.  Even if we install a redisplay handler, it sometimes writes on
   a stdout file.  It is important to redirect every output produced by
   readline, otherwise the curses window will be garbled.  This is implemented
   with a pipe that TUI reads and readline writes to.  A gdb input handler
   is created so that reading the pipe is handled automatically.
   This will probably not work on non-Unix platforms.  The best fix is
   to make readline clean enougth so that is never write on stdout.

   Note SCz/2002-09-01: we now use more readline hooks and it seems that
   with them we don't need the pipe anymore (verified by creating the pipe
   and closing its end so that write causes a SIGPIPE).  The old pipe code
   is still there and can be conditionally removed by
   #undef TUI_USE_PIPE_FOR_READLINE.  */

/* For gdb 5.3, prefer to continue the pipe hack as a backup wheel.  */
#define TUI_USE_PIPE_FOR_READLINE
/*#undef TUI_USE_PIPE_FOR_READLINE*/

/* TUI output files.  */
static struct ui_file *tui_stdout;
static struct ui_file *tui_stderr;
struct ui_out *tui_out;

/* GDB output files in non-curses mode.  */
static struct ui_file *tui_old_stdout;
static struct ui_file *tui_old_stderr;
struct ui_out *tui_old_uiout;

/* Readline previous hooks.  */
static Function *tui_old_rl_getc_function;
static VFunction *tui_old_rl_redisplay_function;
static VFunction *tui_old_rl_prep_terminal;
static VFunction *tui_old_rl_deprep_terminal;
static int tui_old_readline_echoing_p;

/* Readline output stream.
   Should be removed when readline is clean.  */
static FILE *tui_rl_outstream;
static FILE *tui_old_rl_outstream;
#ifdef TUI_USE_PIPE_FOR_READLINE
static int tui_readline_pipe[2];
#endif

/* The last gdb prompt that was registered in readline.
   This may be the main gdb prompt or a secondary prompt.  */
static char *tui_rl_saved_prompt;

static unsigned int tui_handle_resize_during_io (unsigned int);

static void
tui_putc (char c)
{
  char buf[2];

  buf[0] = c;
  buf[1] = 0;
  tui_puts (buf);
}

/* Print the string in the curses command window.  */
void
tui_puts (const char *string)
{
  static int tui_skip_line = -1;
  char c;
  WINDOW *w;

  w = TUI_CMD_WIN->generic.handle;
  while ((c = *string++) != 0)
    {
      /* Catch annotation and discard them.  We need two \032 and
         discard until a \n is seen.  */
      if (c == '\032')
        {
          tui_skip_line++;
        }
      else if (tui_skip_line != 1)
        {
          tui_skip_line = -1;
          waddch (w, c);
        }
      else if (c == '\n')
        tui_skip_line = -1;
    }
  getyx (w, TUI_CMD_WIN->detail.command_info.cur_line,
         TUI_CMD_WIN->detail.command_info.curch);
  TUI_CMD_WIN->detail.command_info.start_line = TUI_CMD_WIN->detail.command_info.cur_line;

  /* We could defer the following.  */
  wrefresh (w);
  fflush (stdout);
}

/* Readline callback.
   Redisplay the command line with its prompt after readline has
   changed the edited text.  */
void
tui_redisplay_readline (void)
{
  int prev_col;
  int height;
  int col, line;
  int c_pos;
  int c_line;
  int in;
  WINDOW *w;
  char *prompt;
  int start_line;

  /* Detect when we temporarily left SingleKey and now the readline
     edit buffer is empty, automatically restore the SingleKey mode.  */
  if (tui_current_key_mode == TUI_ONE_COMMAND_MODE && rl_end == 0)
    tui_set_key_mode (TUI_SINGLE_KEY_MODE);

  if (tui_current_key_mode == TUI_SINGLE_KEY_MODE)
    prompt = "";
  else
    prompt = tui_rl_saved_prompt;
  
  c_pos = -1;
  c_line = -1;
  w = TUI_CMD_WIN->generic.handle;
  start_line = TUI_CMD_WIN->detail.command_info.start_line;
  wmove (w, start_line, 0);
  prev_col = 0;
  height = 1;
  for (in = 0; prompt && prompt[in]; in++)
    {
      waddch (w, prompt[in]);
      getyx (w, line, col);
      if (col < prev_col)
        height++;
      prev_col = col;
    }
  for (in = 0; in < rl_end; in++)
    {
      unsigned char c;
      
      c = (unsigned char) rl_line_buffer[in];
      if (in == rl_point)
	{
          getyx (w, c_line, c_pos);
	}

      if (CTRL_CHAR (c) || c == RUBOUT)
	{
          waddch (w, '^');
          waddch (w, CTRL_CHAR (c) ? UNCTRL (c) : '?');
	}
      else
	{
          waddch (w, c);
	}
      if (c == '\n')
        {
          getyx (w, TUI_CMD_WIN->detail.command_info.start_line,
                 TUI_CMD_WIN->detail.command_info.curch);
        }
      getyx (w, line, col);
      if (col < prev_col)
        height++;
      prev_col = col;
    }
  wclrtobot (w);
  getyx (w, TUI_CMD_WIN->detail.command_info.start_line,
         TUI_CMD_WIN->detail.command_info.curch);
  if (c_line >= 0)
    {
      wmove (w, c_line, c_pos);
      TUI_CMD_WIN->detail.command_info.cur_line = c_line;
      TUI_CMD_WIN->detail.command_info.curch = c_pos;
    }
  TUI_CMD_WIN->detail.command_info.start_line -= height - 1;

  wrefresh (w);
  fflush(stdout);
}

/* Readline callback to prepare the terminal.  It is called once
   each time we enter readline.  Terminal is already setup in curses mode.  */
static void
tui_prep_terminal (int notused1)
{
  /* Save the prompt registered in readline to correctly display it.
     (we can't use gdb_prompt() due to secondary prompts and can't use
     rl_prompt because it points to an alloca buffer).  */
  xfree (tui_rl_saved_prompt);
  tui_rl_saved_prompt = xstrdup (rl_prompt);
}

/* Readline callback to restore the terminal.  It is called once
   each time we leave readline.  There is nothing to do in curses mode.  */
static void
tui_deprep_terminal (void)
{
}

#ifdef TUI_USE_PIPE_FOR_READLINE
/* Read readline output pipe and feed the command window with it.
   Should be removed when readline is clean.  */
static void
tui_readline_output (int code, gdb_client_data data)
{
  int size;
  char buf[256];

  size = read (tui_readline_pipe[0], buf, sizeof (buf) - 1);
  if (size > 0 && tui_active)
    {
      buf[size] = 0;
      tui_puts (buf);
    }
}
#endif

/* Return the portion of PATHNAME that should be output when listing
   possible completions.  If we are hacking filename completion, we
   are only interested in the basename, the portion following the
   final slash.  Otherwise, we return what we were passed.

   Comes from readline/complete.c  */
static char *
printable_part (char *pathname)
{
  char *temp;

  temp = rl_filename_completion_desired ? strrchr (pathname, '/') : (char *)NULL;
#if defined (__MSDOS__)
  if (rl_filename_completion_desired && temp == 0 && isalpha (pathname[0]) && pathname[1] == ':')
    temp = pathname + 1;
#endif
  return (temp ? ++temp : pathname);
}

/* Output TO_PRINT to rl_outstream.  If VISIBLE_STATS is defined and we
   are using it, check for and output a single character for `special'
   filenames.  Return the number of characters we output. */

#define PUTX(c) \
    do { \
      if (CTRL_CHAR (c)) \
        { \
          tui_puts ("^"); \
          tui_putc (UNCTRL (c)); \
          printed_len += 2; \
        } \
      else if (c == RUBOUT) \
	{ \
	  tui_puts ("^?"); \
	  printed_len += 2; \
	} \
      else \
	{ \
	  tui_putc (c); \
	  printed_len++; \
	} \
    } while (0)