bracecomp.c

   1 /* bracecomp.c -- Complete a filename with the possible completions enclosed
   2    in csh-style braces such that the list of completions is available to the
   3    shell. */
   4
   5 /* Original version by tromey@cns.caltech.edu,  Fri Feb  7 1992. */
   6
   7 /* Copyright (C) 1993 Free Software Foundation, Inc.
   8
   9    This file is part of GNU Bash, the Bourne Again SHell.
  10
  11    Bash is free software; you can redistribute it and/or modify it under
  12    the terms of the GNU General Public License as published by the Free
  13    Software Foundation; either version 2, or (at your option) any later
  14    version.
  15
  16    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  17    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19    for more details.
  20
  21    You should have received a copy of the GNU General Public License along
  22    with Bash; see the file COPYING.  If not, write to the Free Software
  23    Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
  24
  25 #include <stdio.h>
  26
  27 #if defined (HAVE_STRING_H)
  28 #  include <string.h>
  29 #else /* !HAVE_STRING_H */
  30 #  include <strings.h>
  31 #endif /* !HAVE_STRING_H */
  32
  33 #include "shell.h"
  34 #include <readline/readline.h>
  35
  36 /* Find greatest common prefix of two strings. */
  37 static int
  38 string_gcd (s1, s2)
  39      char *s1, *s2;
  40 {
  41   register int i;
  42
  43   if (s1 == NULL || s2 == NULL)
  44     return (0);
  45
  46   for (i = 0; *s1 && *s2; ++s1, ++s2, ++i)
  47     {
  48       if (*s1 != *s2)
  49         break;
  50     }
  51
  52   return (i);
  53 }
  54
  55 static char *
  56 really_munge_braces (array, real_start, real_end, gcd_zero)
  57      char **array;
  58      int real_start, real_end, gcd_zero;
  59 {
  60   int start, end, gcd;
  61   char *result, *subterm;
  62   int result_size, flag;
  63
  64   flag = 0;
  65
  66   if (real_start == real_end)
  67     {
  68       if (array[real_start])
  69         return (savestring (array[real_start] + gcd_zero));
  70       else
  71         return (savestring (array[0]));
  72     }
  73
  74   result = (char *) xmalloc (result_size = 1);
  75   *result = '\0';
  76
  77   for (start = real_start; start < real_end; start = end + 1)
  78     {
  79       gcd = strlen (array[start]);
  80       for (end = start + 1; end < real_end; end++)
  81         {
  82           int temp;
  83
  84           temp = string_gcd (array[start], array[end]);
  85
  86           if (temp <= gcd_zero)
  87             break;
  88
  89           gcd = temp;
  90         }
  91       end--;
  92
  93       if (gcd_zero == 0 && start == real_start && end != (real_end - 1))
  94         {
  95           /* In this case, add in a leading '{', because we are at
  96              top level, and there isn't a consistent prefix. */
  97           result_size += 1;
  98           result = (char *) xrealloc (result, result_size);
  99           strcpy (result, "{");
 100           flag++;
 101         }
 102
 103       if (start == end)
 104         subterm = savestring (array[start] + gcd_zero);
 105       else
 106         {
 107           /* If there is more than one element in the subarray,
 108              insert the prefix and an opening brace. */
 109           result_size += gcd - gcd_zero + 1;
 110           result = (char *) xrealloc (result, result_size);
 111           strncat (result, array[start] + gcd_zero, gcd - gcd_zero);
 112           strcat (result, "{");
 113           subterm = really_munge_braces (array, start, end + 1, gcd);
 114           subterm[strlen (subterm) - 1] = '}';
 115         }
 116
 117       result_size += strlen (subterm) + 1;
 118       result = (char *) xrealloc (result, result_size);
 119       strcat (result, subterm);
 120       strcat (result, ",");
 121       free (subterm);
 122     }
 123
 124   if (gcd_zero == 0)
 125     result[strlen (result) - 1] = flag ? '}' : '\0';
 126   return (result);
 127 }
 128
 129 static void
 130 hack_braces_completion (names)
 131      char **names;
 132 {
 133   register int i;
 134   char *temp;
 135
 136   temp = really_munge_braces (names, 1, array_len (names), 0);
 137
 138   for (i = 0; names[i]; ++i)
 139     {
 140       free (names[i]);
 141       names[i] = NULL;
 142     }
 143   names[0] = temp;
 144 }
 145
 146 void
 147 bash_brace_completion ()
 148 {
 149   Function *orig_ignore_func;
 150   Function *orig_entry_func;
 151   CPPFunction *orig_attempt_func;
 152
 153   orig_ignore_func = rl_ignore_some_completions_function;
 154   orig_attempt_func = rl_attempted_completion_function;
 155   orig_entry_func = rl_completion_entry_function;
 156
 157   rl_completion_entry_function = (Function *) filename_completion_function;
 158   rl_attempted_completion_function = NULL;
 159   rl_ignore_some_completions_function = (Function *) hack_braces_completion;
 160
 161   rl_complete_internal (TAB);
 162
 163   rl_ignore_some_completions_function = orig_ignore_func;
 164   rl_attempted_completion_function = orig_attempt_func;
 165   rl_completion_entry_function = orig_entry_func;
 166 }