builtins/history.def

   1 This file is history.def, from which is created history.c.
   2 It implements the builtin "history" in Bash.
   3
   4 Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
   5
   6 This file is part of GNU Bash, the Bourne Again SHell.
   7
   8 Bash is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 1, or (at your option) any later
  11 version.
  12
  13 Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License along
  19 with Bash; see the file COPYING.  If not, write to the Free Software
  20 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 $PRODUCES history.c
  23
  24 $BUILTIN history
  25 $FUNCTION history_builtin
  26 $DEPENDS_ON HISTORY
  27 $SHORT_DOC history [-c] [n] or history -awrn [filename] or history -ps arg [arg...]
  28 Display the history list with line numbers.  Lines listed with
  29 with a `*' have been modified.  Argument of N says to list only
  30 the last N lines.  The -c option causes the history list to be
  31 cleared by deleting all of the entries.  The `-w' option writes out the
  32 current history to the history file;  `-r' means to read the file and
  33 append the contents to the history list instead.  `-a' means
  34 to append history lines from this session to the history file.
  35 Argument `-n' means to read all history lines not already read
  36 from the history file and append them to the history list.  If
  37 FILENAME is given, then that is used as the history file else
  38 if $HISTFILE has a value, that is used, else ~/.bash_history.
  39 If the -s option is supplied, the non-option ARGs are appended to
  40 the history list as a single entry.  The -p option means to perform
  41 history expansion on each ARG and display the result, without storing
  42 anything in the history list.
  43 $END
  44
  45 #include <config.h>
  46
  47 #if defined (HISTORY)
  48 #include "../bashtypes.h"
  49 #ifndef _MINIX
  50 #  include <sys/file.h>
  51 #endif
  52 #include "../posixstat.h"
  53 #include "../filecntl.h"
  54 #include <errno.h>
  55 #include <stdio.h>
  56 #if defined (HAVE_UNISTD_H)
  57 #  include <unistd.h>
  58 #endif
  59
  60 #include "../bashansi.h"
  61
  62 #include "../shell.h"
  63 #include "../bashhist.h"
  64 #include <readline/history.h>
  65 #include "bashgetopt.h"
  66 #include "common.h"
  67
  68 #if !defined (errno)
  69 extern int errno;
  70 #endif
  71
  72 static void display_history ();
  73 static void push_history ();
  74 static int expand_and_print_history ();
  75
  76 #define AFLAG   0x01
  77 #define RFLAG   0x02
  78 #define WFLAG   0x04
  79 #define NFLAG   0x08
  80 #define SFLAG   0x10
  81 #define PFLAG   0x20
  82 #define CFLAG   0x40
  83
  84 int
  85 history_builtin (list)
  86      WORD_LIST *list;
  87 {
  88   int flags, opt, result;
  89   char *filename;
  90
  91   flags = 0;
  92   reset_internal_getopt ();
  93   while ((opt = internal_getopt (list, "acnpsrw")) != -1)
  94     {
  95       switch (opt)
  96         {
  97         case 'a':
  98           flags |= AFLAG;
  99           break;
 100         case 'c':
 101           flags |= CFLAG;
 102           break;
 103         case 'n':
 104           flags |= NFLAG;
 105           break;
 106         case 'r':
 107           flags |= RFLAG;
 108           break;
 109         case 'w':
 110           flags |= WFLAG;
 111           break;
 112         case 's':
 113           flags |= SFLAG;
 114           break;
 115         case 'p':
 116 #if defined (BANG_HISTORY)
 117           flags |= PFLAG;
 118 #endif
 119           break;
 120         default:
 121           builtin_usage ();
 122           return (EX_USAGE);
 123         }
 124     }
 125   list = loptend;
 126
 127   opt = flags & (AFLAG|RFLAG|WFLAG|NFLAG);
 128   if (opt && opt != AFLAG && opt != RFLAG && opt != WFLAG && opt != NFLAG)
 129     {
 130       builtin_error ("cannot use more than one of -anrw");
 131       return (EXECUTION_FAILURE);
 132     }
 133
 134   /* clear the history, but allow other arguments to add to it again. */
 135   if (flags & CFLAG)
 136     {
 137       clear_history ();
 138       if (list == 0)
 139         return (EXECUTION_SUCCESS);
 140     }
 141
 142   if (flags & SFLAG)
 143     {
 144       if (list)
 145         push_history (list);
 146       return (EXECUTION_SUCCESS);
 147     }
 148 #if defined (BANG_HISTORY)
 149   else if (flags & PFLAG)
 150     {
 151       if (list)
 152         return (expand_and_print_history (list));
 153       return (EXECUTION_SUCCESS);
 154     }
 155 #endif
 156   else if ((flags & (AFLAG|RFLAG|NFLAG|WFLAG|CFLAG)) == 0)
 157     {
 158       display_history (list);
 159       return (EXECUTION_SUCCESS);
 160     }
 161
 162   filename = list ? list->word->word : get_string_value ("HISTFILE");
 163   result = EXECUTION_SUCCESS;
 164
 165   if (flags & AFLAG)            /* Append session's history to file. */
 166     result = maybe_append_history (filename);
 167   else if (flags & WFLAG)       /* Write entire history. */
 168     result = write_history (filename);
 169   else if (flags & RFLAG)       /* Read entire file. */
 170     result = read_history (filename);
 171   else if (flags & NFLAG)       /* Read `new' history from file. */
 172     {
 173       /* Read all of the lines in the file that we haven't already read. */
 174       using_history ();
 175       result = read_history_range (filename, history_lines_in_file, -1);
 176       using_history ();
 177       history_lines_in_file = where_history ();
 178     }
 179
 180   return (result ? EXECUTION_FAILURE : EXECUTION_SUCCESS);
 181 }
 182
 183 /* Accessors for HIST_ENTRY lists that are called HLIST. */
 184 #define histline(i) (hlist[(i)]->line)
 185 #define histdata(i) (hlist[(i)]->data)
 186
 187 static void
 188 display_history (list)
 189      WORD_LIST *list;
 190 {
 191   register int i;
 192   int limited, limit;
 193   HIST_ENTRY **hlist;
 194
 195   if (list)
 196     {
 197       limited = 1;
 198       limit = get_numeric_arg (list, 0);
 199     }
 200   else
 201     limited = limit = 0;
 202
 203   hlist = history_list ();
 204
 205   if (hlist)
 206     {
 207       for (i = 0;  hlist[i]; i++)
 208         ;
 209
 210       if (limit < 0)
 211         limit = -limit;
 212
 213       if ((limited == 0)  || ((i -= limit) < 0))
 214         i = 0;
 215
 216       while (hlist[i])
 217         {
 218           QUIT;
 219           printf ("%5d%c %s\n", i + history_base,
 220                   histdata(i) ? '*' : ' ',
 221                   histline(i));
 222           i++;
 223         }
 224     }
 225 }
 226
 227 static int
 228 delete_last_history ()
 229 {
 230   register int i;
 231   HIST_ENTRY **hlist, *histent, *discard;
 232
 233   hlist = history_list ();
 234   if (hlist == NULL)
 235     return 0;
 236
 237   for (i = 0; hlist[i]; i++)
 238     ;
 239   i--;
 240
 241   /* History_get () takes a parameter that must be offset by history_base. */
 242   histent = history_get (history_base + i);     /* Don't free this */
 243   if (histent == NULL)
 244     return 0;
 245
 246   discard = remove_history (i);
 247   if (discard)
 248     {
 249       if (discard->line)
 250         free (discard->line);
 251       free ((char *) discard);
 252     }
 253   return (1);
 254 }
 255
 256 /* Remove the last entry in the history list and add each argument in
 257    LIST to the history. */
 258 static void
 259 push_history (list)
 260      WORD_LIST *list;
 261 {
 262   char *s;
 263
 264   if (hist_last_line_added && delete_last_history () == 0)
 265     return;
 266   s = string_list (list);
 267   maybe_add_history (s);        /* Obeys HISTCONTROL setting. */
 268   free (s);
 269 }
 270
 271 #if defined (BANG_HISTORY)
 272 static int
 273 expand_and_print_history (list)
 274      WORD_LIST *list;
 275 {
 276   char *s;
 277   int r, result;
 278
 279   if (hist_last_line_added && delete_last_history () == 0)
 280     return EXECUTION_FAILURE;
 281   result = EXECUTION_SUCCESS;
 282   while (list)
 283     {
 284       r = history_expand (list->word->word, &s);
 285       if (r < 0)
 286         {
 287           builtin_error ("%s: history expansion failed", list->word->word);
 288           result = EXECUTION_FAILURE;
 289         }
 290       else
 291         {
 292           fputs (s, stdout);
 293           putchar ('\n');
 294         }
 295       FREE (s);
 296       list = list->next;
 297     }
 298   fflush (stdout);
 299   return result;
 300 }
 301 #endif /* BANG_HISTORY */
 302 #endif /* HISTORY */