utils.c

早期freebsd实现

	      lineptr++;
	    }
      
	  if (chars_printed >= chars_per_line)
	    {
	      unsigned int save_chars = chars_printed;

	      chars_printed = 0;
	      lines_printed++;
	      /* If we aren't actually wrapping, don't output newline --
		 if chars_per_line is right, we probably just overflowed
		 anyway; if it's wrong, let us keep going.  */
	      if (wrap_column)
		putc ('\n', stream);

	      /* Possible new page.  */
	      if (lines_printed >= lines_per_page - 1)
		prompt_for_continue ();

	      /* Now output indentation and wrapped string */
	      if (wrap_column)
		{
		  if (wrap_indent)
		    fputs (wrap_indent, stream);
		  *wrap_pointer = '\0';		/* Null-terminate saved stuff */
		  fputs (wrap_buffer, stream);	/* and eject it */
		  /* FIXME, this strlen is what prevents wrap_indent from
		     containing tabs.  However, if we recurse to print it
		     and count its chars, we risk trouble if wrap_indent is
		     longer than (the user settable) chars_per_line. 
		     Note also that this can set chars_printed > chars_per_line
		     if we are printing a long string.  */
		  chars_printed = strlen (wrap_indent)
				+ (save_chars - wrap_column);
		  wrap_pointer = wrap_buffer;	/* Reset buffer */
		  wrap_buffer[0] = '\0';
		  wrap_column = 0;		/* And disable fancy wrap */
 		}
	    }
	}

      if (*lineptr == '\n')
	{
	  chars_printed = 0;
	  wrap_here ((char *)0);  /* Spit out chars, cancel further wraps */
	  lines_printed++;
	  putc ('\n', stream);
	  lineptr++;
	}
    }
}


/* fputs_demangled is a variant of fputs_filtered that
   demangles g++ names.*/

void
fputs_demangled (linebuffer, stream, arg_mode)
     char *linebuffer;
     FILE *stream;
     int arg_mode;
{
#define SYMBOL_MAX 1024

#define SYMBOL_CHAR(c) (isascii(c) \
  && (isalnum(c) || (c) == '_' || (c) == CPLUS_MARKER))

  char buf[SYMBOL_MAX+1];
# define DMSLOP 5		/* How much room to leave in buf */
  char *p;

  if (linebuffer == NULL)
    return;

  /* If user wants to see raw output, no problem.  */
  if (!demangle) {
    fputs_filtered (linebuffer, stream);
    return;
  }

  p = linebuffer;

  while ( *p != (char) 0 ) {
    int i = 0;

    /* collect non-interesting characters into buf */
    while (*p != (char) 0 && !SYMBOL_CHAR(*p) && i < (int)sizeof(buf)-DMSLOP ) {
      buf[i++] = *p;
      p++;
    }
    if (i > 0) {
      /* output the non-interesting characters without demangling */
      buf[i] = (char) 0;
      fputs_filtered(buf, stream);
      i = 0;  /* reset buf */
    }

    /* and now the interesting characters */
    while (i < SYMBOL_MAX
     && *p != (char) 0
     && SYMBOL_CHAR(*p)
     && i < (int)sizeof(buf) - DMSLOP) {
      buf[i++] = *p;
      p++;
    }
    buf[i] = (char) 0;
    if (i > 0) {
      char * result;
      
      if ( (result = cplus_demangle(buf, arg_mode)) != NULL ) {
	fputs_filtered(result, stream);
	free(result);
      }
      else {
	fputs_filtered(buf, stream);
      }
    }
  }
}

/* Print a variable number of ARGS using format FORMAT.  If this
   information is going to put the amount written (since the last call
   to REINITIALIZE_MORE_FILTER or the last page break) over the page size,
   print out a pause message and do a gdb_readline to get the users
   permision to continue.

   Unlike fprintf, this function does not return a value.

   We implement three variants, vfprintf (takes a vararg list and stream),
   fprintf (takes a stream to write on), and printf (the usual).

   Note that this routine has a restriction that the length of the
   final output line must be less than 255 characters *or* it must be
   less than twice the size of the format string.  This is a very
   arbitrary restriction, but it is an internal restriction, so I'll
   put it in.  This means that the %s format specifier is almost
   useless; unless the caller can GUARANTEE that the string is short
   enough, fputs_filtered should be used instead.

   Note also that a longjmp to top level may occur in this routine
   (since prompt_for_continue may do so) so this routine should not be
   called when cleanups are not in place.  */

#define	MIN_LINEBUF	255

void
vfprintf_filtered (stream, format, args)
     FILE *stream;
     char *format;
     va_list args;
{
  char line_buf[MIN_LINEBUF+10];
  char *linebuffer = line_buf;
  int format_length;

  format_length = strlen (format);

  /* Reallocate buffer to a larger size if this is necessary.  */
  if (format_length * 2 > MIN_LINEBUF)
    {
      linebuffer = alloca (10 + format_length * 2);
    }

  /* This won't blow up if the restrictions described above are
     followed.   */
  vsprintf (linebuffer, format, args);

  fputs_filtered (linebuffer, stream);
}

/* VARARGS */
void
fprintf_filtered (va_alist)
     va_dcl
{
  va_list args;
  FILE *stream;
  char *format;

  va_start (args);
  stream = va_arg (args, FILE *);
  format = va_arg (args, char *);

  /* This won't blow up if the restrictions described above are
     followed.   */
  vfprintf_filtered (stream, format, args);
  va_end (args);
}

/* Like fprintf_filtered, but prints it's result indent.
   Called as fprintfi_filtered (spaces, format, arg1, arg2, ...); */

/* VARARGS */
void
fprintfi_filtered (va_alist)
     va_dcl
{
  va_list args;
  int spaces;
  FILE *stream;
  char *format;

  va_start (args);
  spaces = va_arg (args, int);
  stream = va_arg (args, FILE *);
  format = va_arg (args, char *);
  print_spaces_filtered (spaces, stream);

  /* This won't blow up if the restrictions described above are
     followed.   */
  vfprintf_filtered (stream, format, args);
  va_end (args);
}

/* VARARGS */
void
printf_filtered (va_alist)
     va_dcl
{
  va_list args;
  char *format;

  va_start (args);
  format = va_arg (args, char *);

  vfprintf_filtered (stdout, format, args);
  va_end (args);
}

/* Like printf_filtered, but prints it's result indented.
   Called as printfi_filtered (spaces, format, arg1, arg2, ...); */

/* VARARGS */
void
printfi_filtered (va_alist)
     va_dcl
{
  va_list args;
  int spaces;
  char *format;

  va_start (args);
  spaces = va_arg (args, int);
  format = va_arg (args, char *);
  print_spaces_filtered (spaces, stdout);
  vfprintf_filtered (stdout, format, args);
  va_end (args);
}

/* Easy -- but watch out!

   This routine is *not* a replacement for puts()!  puts() appends a newline.
   This one doesn't, and had better not!  */

void
puts_filtered (string)
     char *string;
{
  fputs_filtered (string, stdout);
}

/* Return a pointer to N spaces and a null.  The pointer is good
   until the next call to here.  */
char *
n_spaces (n)
     int n;
{
  register char *t;
  static char *spaces;
  static int max_spaces;

  if (n > max_spaces)
    {
      if (spaces)
	free (spaces);
      spaces = (char *) xmalloc (n+1);
      for (t = spaces+n; t != spaces;)
	*--t = ' ';
      spaces[n] = '\0';
      max_spaces = n;
    }

  return spaces + max_spaces - n;
}

/* Print N spaces.  */
void
print_spaces_filtered (n, stream)
     int n;
     FILE *stream;
{
  fputs_filtered (n_spaces (n), stream);
}

/* C++ demangler stuff.  */

/* Make a copy of a symbol, applying C++ demangling if demangling is enabled
   and a demangled version exists.  Note that the value returned from
   cplus_demangle is already allocated in malloc'd memory. */

char *
strdup_demangled (name)
     const char *name;
{
  char *demangled = NULL;

  if (demangle)
    {
      demangled = cplus_demangle (name, DMGL_PARAMS | DMGL_ANSI);
    }
  return ((demangled != NULL) ? demangled : strdup (name));
}


/* Print NAME on STREAM, demangling if necessary.  */
void
fprint_symbol (stream, name)
     FILE *stream;
     char *name;
{
  char *demangled;
  if ((!demangle)
      || NULL == (demangled = cplus_demangle (name, DMGL_PARAMS | DMGL_ANSI)))
    fputs_filtered (name, stream);
  else
    {
      fputs_filtered (demangled, stream);
      free (demangled);
    }
}

/* Do a strcmp() type operation on STRING1 and STRING2, ignoring any
   differences in whitespace.  Returns 0 if they match, non-zero if they
   don't (slightly different than strcmp()'s range of return values).
   
   As an extra hack, string1=="FOO(ARGS)" matches string2=="FOO".
   This "feature" is useful for demangle_and_match(), which is used
   when searching for matching C++ function names (such as if the
   user types 'break FOO', where FOO is a mangled C++ function). */

int
strcmp_iw (string1, string2)
     const char *string1;
     const char *string2;
{
  while ((*string1 != '\0') && (*string2 != '\0'))
    {
      while (isspace (*string1))
	{
	  string1++;
	}
      while (isspace (*string2))
	{
	  string2++;
	}
      if (*string1 != *string2)
	{
	  break;
	}
      if (*string1 != '\0')
	{
	  string1++;
	  string2++;
	}
    }
  return (*string1 != '\0' && *string1 != '(') || (*string2 != '\0');
}

/* Demangle NAME and compare the result with LOOKFOR, ignoring any differences
   in whitespace.
   
   If a match is found, returns a pointer to the demangled version of NAME
   in malloc'd memory, which needs to be freed by the caller after use.
   If a match is not found, returns NULL.

   OPTIONS is a flags word that controls the demangling process and is just
   passed on to the demangler.

   When the caller sees a non-NULL result, it knows that NAME is the mangled
   equivalent of LOOKFOR, and it can use either NAME, the "official demangled"
   version of NAME (the return value) or the "unofficial demangled" version
   of NAME (LOOKFOR, which it already knows). */

char *
demangle_and_match (name, lookfor, options)
     const char *name;
     const char *lookfor;
     int options;
{
  char *demangled;

  if ((demangled = cplus_demangle (name, options)) != NULL)
    {
      if (strcmp_iw (demangled, lookfor) != 0)
	{
	  free (demangled);
	  demangled = NULL;
	}
    }
  return (demangled);
}

#ifdef TIOCGWINSZ
#ifdef SIGWINCH
static void
sigwinch()
{
	struct winsize win;

	if (ioctl(0, TIOCGWINSZ, (char *)&win) < 0) {
		perror("TIOCGWINSZ");
		return;
	}
	lines_per_page = win.ws_row;
	chars_per_line = win.ws_col;
}

#ifndef SIGWINCH_HANDLER
#define SIGWINCH_HANDLER sigwinch
#endif

#endif

termdim()
{
	SIGWINCH_HANDLER();
#ifdef SIGWINCH
	signal(SIGWINCH, SIGWINCH_HANDLER);
#endif
}

#else
/* Initialize the screen height and width from termcap.  */
termdim()
{
	register int v;
	register char *cp;
	/* 2048 is large enough for all known terminals, according to the
	   GNU termcap manual.  */
	char term_buffer[2048];

	if ((termtype = getenv ("TERM")) == 0 || tgetent(term_buffer, cp) <= 0)
		return;

	v = tgetnum("li");
	if (v >= 0)
		lines_per_page = v;
	else
		/* The number of lines per page is not mentioned
		   in the terminal description.  This probably means
		   that paging is not useful (e.g. emacs shell window),
		   so disable paging.  */
		lines_per_page = UINT_MAX;
	
	v = tgetnum("co");
	if (v >= 0)
		chars_per_line = v;
}
#endif

void
_initialize_utils ()
{
  struct cmd_list_element *c;

  c = add_set_cmd ("width", class_support, var_uinteger, 
		  (char *)&chars_per_line,
		  "Set number of characters gdb thinks are in a line.",
		  &setlist);
  add_show_from_set (c, &showlist);
  c->function.sfunc = set_width_command;

  add_show_from_set
    (add_set_cmd ("height", class_support,
		  var_uinteger, (char *)&lines_per_page,
		  "Set number of lines gdb thinks are in a page.", &setlist),
     &showlist);
  
  /* These defaults will be used if we are unable to get the correct
     values from termcap.  */
#if defined(__GO32__)
  lines_per_page = ScreenRows();
  chars_per_line = ScreenCols();
#else  
  lines_per_page = 24;
  chars_per_line = 80;
  termdim();
#endif
  /* If the output is not a terminal, don't paginate it.  */
  if (!ISATTY (stdout))
    lines_per_page = UINT_MAX;

  set_width_command ((char *)NULL, 0, c);

  add_show_from_set
    (add_set_cmd ("demangle", class_support, var_boolean, 
		  (char *)&demangle,
		"Set demangling of encoded C++ names when displaying symbols.",
		  &setprintlist),
     &showprintlist);

  add_show_from_set
    (add_set_cmd ("sevenbit-strings", class_support, var_boolean, 
		  (char *)&sevenbit_strings,
   "Set printing of 8-bit characters in strings as \\nnn.",
		  &setprintlist),
     &showprintlist);

  add_show_from_set
    (add_set_cmd ("asm-demangle", class_support, var_boolean, 
		  (char *)&asm_demangle,
	"Set demangling of C++ names in disassembly listings.",
		  &setprintlist),
     &showprintlist);
}

/* Machine specific function to handle SIGWINCH signal. */

#ifdef  SIGWINCH_HANDLER_BODY
        SIGWINCH_HANDLER_BODY
#endif