complete.c

UNIX下SH的实现源码

/* complete.c -- filename completion for readline. */

/* Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc.

   This file is part of the GNU Readline Library, a library for
   reading lines of text with interactive input and history editing.

   The GNU Readline Library 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, or
   (at your option) any later version.

   The GNU Readline Library 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.

   The GNU General Public License is often shipped with GNU software, and
   is generally kept in a file called COPYING or LICENSE.  If you do not
   have a copy of the license, write to the Free Software Foundation,
   59 Temple Place, Suite 330, Boston, MA 02111 USA. */
#define READLINE_LIBRARY

#if defined (HAVE_CONFIG_H)
#  include <config.h>
#endif

#include <sys/types.h>
#include <fcntl.h>
#if defined (HAVE_SYS_FILE_H)
#include <sys/file.h>
#endif

#if defined (HAVE_UNISTD_H)
#  include <unistd.h>
#endif /* HAVE_UNISTD_H */

#if defined (HAVE_STDLIB_H)
#  include <stdlib.h>
#else
#  include "ansi_stdlib.h"
#endif /* HAVE_STDLIB_H */

#include <stdio.h>

#include <errno.h>
#if !defined (errno)
extern int errno;
#endif /* !errno */

#include <pwd.h>
#if !defined (HAVE_GETPW_DECLS)
extern struct passwd *getpwent ();
#endif /* USG && !HAVE_GETPW_DECLS */

/* ISC systems don't define getpwent() if _POSIX_SOURCE is defined. */
#if defined (isc386) && defined (_POSIX_SOURCE)
#  if defined (__STDC__)
extern struct passwd *getpwent (void);
#  else
extern struct passwd *getpwent ();
#  endif /* !__STDC__ */
#endif /* isc386 && _POSIX_SOURCE */

#include "posixdir.h"
#include "posixstat.h"

/* System-specific feature definitions and include files. */
#include "rldefs.h"

/* Some standard library routines. */
#include "readline.h"
#include "xmalloc.h"
#include "rlprivate.h"

#ifdef __STDC__
typedef int QSFUNC (const void *, const void *);
#else
typedef int QSFUNC ();
#endif

/* If non-zero, then this is the address of a function to call when
   completing a word would normally display the list of possible matches.
   This function is called instead of actually doing the display.
   It takes three arguments: (char **matches, int num_matches, int max_length)
   where MATCHES is the array of strings that matched, NUM_MATCHES is the
   number of strings in that array, and MAX_LENGTH is the length of the
   longest string in that array. */
VFunction *rl_completion_display_matches_hook = (VFunction *)NULL;

/* Forward declarations for functions defined and used in this file. */
char *filename_completion_function __P((char *, int));
char **completion_matches __P((char *, CPFunction *));

#if defined (VISIBLE_STATS)
#  if !defined (X_OK)
#    define X_OK 1
#  endif
static int stat_char __P((char *));
#endif

static char *rl_quote_filename __P((char *, int, char *));
static char *rl_strpbrk __P((char *, char *));

static char **remove_duplicate_matches __P((char **));
static void insert_match __P((char *, int, int, char *));
static int append_to_match __P((char *, int, int));
static void insert_all_matches __P((char **, int, char *));
static void display_matches __P((char **));
static int compute_lcd_of_matches __P((char **, int, char *));

/* **************************************************************** */
/*								    */
/*	Completion matching, from readline's point of view.	    */
/*								    */
/* **************************************************************** */

/* Variables known only to the readline library. */

/* If non-zero, non-unique completions always show the list of matches. */
int _rl_complete_show_all = 0;

/* If non-zero, completed directory names have a slash appended. */
int _rl_complete_mark_directories = 1;

/* If non-zero, completions are printed horizontally in alphabetical order,
   like `ls -x'. */
int _rl_print_completions_horizontally;

/* Non-zero means that case is not significant in filename completion. */
#if defined (__MSDOS__) && !defined (__DJGPP__)
int _rl_completion_case_fold = 1;
#else
int _rl_completion_case_fold;
#endif

/* Global variables available to applications using readline. */

#if defined (VISIBLE_STATS)
/* Non-zero means add an additional character to each filename displayed
   during listing completion iff rl_filename_completion_desired which helps
   to indicate the type of file being listed. */
int rl_visible_stats = 0;
#endif /* VISIBLE_STATS */

/* If non-zero, then this is the address of a function to call when
   completing on a directory name.  The function is called with
   the address of a string (the current directory name) as an arg. */
Function *rl_directory_completion_hook = (Function *)NULL;

/* Non-zero means readline completion functions perform tilde expansion. */
int rl_complete_with_tilde_expansion = 0;

/* Pointer to the generator function for completion_matches ().
   NULL means to use filename_completion_function (), the default filename
   completer. */
Function *rl_completion_entry_function = (Function *)NULL;

/* Pointer to alternative function to create matches.
   Function is called with TEXT, START, and END.
   START and END are indices in RL_LINE_BUFFER saying what the boundaries
   of TEXT are.
   If this function exists and returns NULL then call the value of
   rl_completion_entry_function to try to match, otherwise use the
   array of strings returned. */
CPPFunction *rl_attempted_completion_function = (CPPFunction *)NULL;

/* Non-zero means to suppress normal filename completion after the
   user-specified completion function has been called. */
int rl_attempted_completion_over = 0;

/* Set to a character indicating the type of completion being performed
   by rl_complete_internal, available for use by application completion
   functions. */
int rl_completion_type = 0;

/* Up to this many items will be displayed in response to a
   possible-completions call.  After that, we ask the user if
   she is sure she wants to see them all. */
int rl_completion_query_items = 100;

/* The basic list of characters that signal a break between words for the
   completer routine.  The contents of this variable is what breaks words
   in the shell, i.e. " \t\n\"\\'`@$><=" */
char *rl_basic_word_break_characters = " \t\n\"\\'`@$><=;|&{(";

/* List of basic quoting characters. */
char *rl_basic_quote_characters = "\"'";

/* The list of characters that signal a break between words for
   rl_complete_internal.  The default list is the contents of
   rl_basic_word_break_characters.  */
char *rl_completer_word_break_characters = (char *)NULL;

/* List of characters which can be used to quote a substring of the line.
   Completion occurs on the entire substring, and within the substring
   rl_completer_word_break_characters are treated as any other character,
   unless they also appear within this list. */
char *rl_completer_quote_characters = (char *)NULL;

/* List of characters that should be quoted in filenames by the completer. */
char *rl_filename_quote_characters = (char *)NULL;

/* List of characters that are word break characters, but should be left
   in TEXT when it is passed to the completion function.  The shell uses
   this to help determine what kind of completing to do. */
char *rl_special_prefixes = (char *)NULL;

/* If non-zero, then disallow duplicates in the matches. */
int rl_ignore_completion_duplicates = 1;

/* Non-zero means that the results of the matches are to be treated
   as filenames.  This is ALWAYS zero on entry, and can only be changed
   within a completion entry finder function. */
int rl_filename_completion_desired = 0;

/* Non-zero means that the results of the matches are to be quoted using
   double quotes (or an application-specific quoting mechanism) if the
   filename contains any characters in rl_filename_quote_chars.  This is
   ALWAYS non-zero on entry, and can only be changed within a completion
   entry finder function. */
int rl_filename_quoting_desired = 1;

/* This function, if defined, is called by the completer when real
   filename completion is done, after all the matching names have been
   generated. It is passed a (char**) known as matches in the code below.
   It consists of a NULL-terminated array of pointers to potential
   matching strings.  The 1st element (matches[0]) is the maximal
   substring that is common to all matches. This function can re-arrange
   the list of matches as required, but all elements of the array must be
   free()'d if they are deleted. The main intent of this function is
   to implement FIGNORE a la SunOS csh. */
Function *rl_ignore_some_completions_function = (Function *)NULL;

/* Set to a function to quote a filename in an application-specific fashion.
   Called with the text to quote, the type of match found (single or multiple)
   and a pointer to the quoting character to be used, which the function can
   reset if desired. */
CPFunction *rl_filename_quoting_function = rl_quote_filename;
         
/* Function to call to remove quoting characters from a filename.  Called
   before completion is attempted, so the embedded quotes do not interfere
   with matching names in the file system.  Readline doesn't do anything
   with this; it's set only by applications. */
CPFunction *rl_filename_dequoting_function = (CPFunction *)NULL;

/* Function to call to decide whether or not a word break character is
   quoted.  If a character is quoted, it does not break words for the
   completer. */
Function *rl_char_is_quoted_p = (Function *)NULL;

/* Character appended to completed words when at the end of the line.  The
   default is a space. */
int rl_completion_append_character = ' ';

/* If non-zero, inhibit completion (temporarily). */
int rl_inhibit_completion;

/* Variables local to this file. */

/* Local variable states what happened during the last completion attempt. */
static int completion_changed_buffer;

/*************************************/
/*				     */
/*    Bindable completion functions  */
/*				     */
/*************************************/

/* Complete the word at or before point.  You have supplied the function
   that does the initial simple matching selection algorithm (see
   completion_matches ()).  The default is to do filename completion. */
int
rl_complete (ignore, invoking_key)
     int ignore, invoking_key;
{
  if (rl_inhibit_completion)
    return (rl_insert (ignore, invoking_key));
  else if (rl_last_func == rl_complete && !completion_changed_buffer)
    return (rl_complete_internal ('?'));
  else if (_rl_complete_show_all)
    return (rl_complete_internal ('!'));
  else
    return (rl_complete_internal (TAB));
}

/* List the possible completions.  See description of rl_complete (). */
int
rl_possible_completions (ignore, invoking_key)
     int ignore, invoking_key;
{
  return (rl_complete_internal ('?'));
}

int
rl_insert_completions (ignore, invoking_key)
     int ignore, invoking_key;
{
  return (rl_complete_internal ('*'));
}

/************************************/
/*				    */
/*    Completion utility functions  */
/*				    */
/************************************/

/* Find the first occurrence in STRING1 of any character from STRING2.
   Return a pointer to the character in STRING1. */
static char *
rl_strpbrk (string1, string2)
     char *string1, *string2;
{
  register char *scan;

  for (; *string1; string1++)
    {
      for (scan = string2; *scan; scan++)
	{
	  if (*string1 == *scan)
	    {
	      return (string1);
	    }
	}
    }
  return ((char *)NULL);
}

/* The user must press "y" or "n". Non-zero return means "y" pressed. */
static int
get_y_or_n ()
{
  int c;

  for (;;)
    {
      c = rl_read_key ();
      if (c == 'y' || c == 'Y' || c == ' ')
	return (1);
      if (c == 'n' || c == 'N' || c == RUBOUT)
	return (0);
      if (c == ABORT_CHAR)
	_rl_abort_internal ();
      ding ();
    }
}

#if defined (VISIBLE_STATS)
/* Return the character which best describes FILENAME.
     `@' for symbolic links
     `/' for directories
     `*' for executables
     `=' for sockets
     `|' for FIFOs
     `%' for character special devices
     `#' for block special devices */
static int
stat_char (filename)
     char *filename;
{
  struct stat finfo;
  int character, r;

#if defined (HAVE_LSTAT) && defined (S_ISLNK)
  r = lstat (filename, &finfo);
#else
  r = stat (filename, &finfo);
#endif

  if (r == -1)
    return (0);

  character = 0;
  if (S_ISDIR (finfo.st_mode))
    character = '/';
#if defined (S_ISCHR)
  else if (S_ISCHR (finfo.st_mode))
    character = '%';
#endif /* S_ISCHR */
#if defined (S_ISBLK)
  else if (S_ISBLK (finfo.st_mode))
    character = '#';
#endif /* S_ISBLK */
#if defined (S_ISLNK)
  else if (S_ISLNK (finfo.st_mode))
    character = '@';
#endif /* S_ISLNK */
#if defined (S_ISSOCK)
  else if (S_ISSOCK (finfo.st_mode))
    character = '=';
#endif /* S_ISSOCK */
#if defined (S_ISFIFO)
  else if (S_ISFIFO (finfo.st_mode))
    character = '|';
#endif
  else if (S_ISREG (finfo.st_mode))
    {
      if (access (filename, X_OK) == 0)
	character = '*';
    }
  return (character);
}
#endif /* VISIBLE_STATS */

/* 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. */
static char *
printable_part (pathname)
      char *pathname;
{
  char *temp;

  temp = rl_filename_completion_desired ? strrchr (pathname, '/') : (char *)NULL;
#if defined (HAVE_DOS_STYLE_FILE_SYSTEM)
  if (temp == 0 && rl_filename_completion_desired
      && (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)) \
        { \
          putc ('^', rl_outstream); \
          putc (UNCTRL (c), rl_outstream); \
          printed_len += 2; \
        } \
      else if (c == RUBOUT) \
	{ \
	  putc ('^', rl_outstream); \
	  putc ('?', rl_outstream); \
	  printed_len += 2; \
	} \
      else \
	{ \
	  putc (c, rl_outstream); \
	  printed_len++; \
	} \
    } while (0)

static int
print_filename (to_print, full_pathname)
     char *to_print, *full_pathname;