bashhist.c~

   1 /* bashhist.c -- bash interface to the GNU history library. */
   2
   3 /* Copyright (C) 1993-2010 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "config.h"
  22
  23 #if defined (HISTORY)
  24
  25 #if defined (HAVE_UNISTD_H)
  26 #  ifdef _MINIX
  27 #    include <sys/types.h>
  28 #  endif
  29 #  include <unistd.h>
  30 #endif
  31
  32 #include "bashtypes.h"
  33 #include <stdio.h>
  34 #include <errno.h>
  35 #include "bashansi.h"
  36 #include "posixstat.h"
  37 #include "filecntl.h"
  38
  39 #include "bashintl.h"
  40
  41 #if defined (SYSLOG_HISTORY)
  42 #  include <syslog.h>
  43 #endif
  44
  45 #include "shell.h"
  46 #include "flags.h"
  47 #include "input.h"
  48 #include "parser.h"     /* for the struct dstack stuff. */
  49 #include "pathexp.h"    /* for the struct ignorevar stuff */
  50 #include "bashhist.h"   /* matching prototypes and declarations */
  51 #include "builtins/common.h"
  52
  53 #include <readline/history.h>
  54 #include <glob/glob.h>
  55 #include <glob/strmatch.h>
  56
  57 #if defined (READLINE)
  58 #  include "bashline.h"
  59 extern int rl_done, rl_dispatching;     /* should really include readline.h */
  60 #endif
  61
  62 #if !defined (errno)
  63 extern int errno;
  64 #endif
  65
  66 static int histignore_item_func __P((struct ign *));
  67 static int check_history_control __P((char *));
  68 static void hc_erasedups __P((char *));
  69 static void really_add_history __P((char *));
  70
  71 static struct ignorevar histignore =
  72 {
  73   "HISTIGNORE",
  74   (struct ign *)0,
  75   0,
  76   (char *)0,
  77   (sh_iv_item_func_t *)histignore_item_func,
  78 };
  79
  80 #define HIGN_EXPAND 0x01
  81
  82 /* Declarations of bash history variables. */
  83 /* Non-zero means to remember lines typed to the shell on the history
  84    list.  This is different than the user-controlled behaviour; this
  85    becomes zero when we read lines from a file, for example. */
  86 int remember_on_history = 1;
  87 int enable_history_list = 1;    /* value for `set -o history' */
  88
  89 /* The number of lines that Bash has added to this history session.  The
  90    difference between the number of the top element in the history list
  91    (offset from history_base) and the number of lines in the history file.
  92    Appending this session's history to the history file resets this to 0. */
  93 int history_lines_this_session;
  94
  95 /* The number of lines that Bash has read from the history file. */
  96 int history_lines_in_file;
  97
  98 #if defined (BANG_HISTORY)
  99 /* Non-zero means do no history expansion on this line, regardless
 100    of what history_expansion says. */
 101 int history_expansion_inhibited;
 102 #endif
 103
 104 /* With the old default, every line was saved in the history individually.
 105    I.e., if the user enters:
 106         bash$ for i in a b c
 107         > do
 108         > echo $i
 109         > done
 110    Each line will be individually saved in the history.
 111         bash$ history
 112         10  for i in a b c
 113         11  do
 114         12  echo $i
 115         13  done
 116         14  history
 117    If the variable command_oriented_history is set, multiple lines
 118    which form one command will be saved as one history entry.
 119         bash$ for i in a b c
 120         > do
 121         > echo $i
 122         > done
 123         bash$ history
 124         10  for i in a b c
 125     do
 126     echo $i
 127     done
 128         11  history
 129    The user can then recall the whole command all at once instead
 130    of just being able to recall one line at a time.
 131
 132    This is now enabled by default.
 133    */
 134 int command_oriented_history = 1;
 135
 136 /* Set to 1 if the first line of a possibly-multi-line command was saved
 137    in the history list.  Managed by maybe_add_history(), but global so
 138    the history-manipluating builtins can see it. */
 139 int current_command_first_line_saved = 0;
 140
 141 /* Non-zero means to store newlines in the history list when using
 142    command_oriented_history rather than trying to use semicolons. */
 143 int literal_history;
 144
 145 /* Non-zero means to append the history to the history file at shell
 146    exit, even if the history has been stifled. */
 147 int force_append_history;
 148
 149 /* A nit for picking at history saving.  Flags have the following values:
 150
 151    Value == 0 means save all lines parsed by the shell on the history.
 152    Value & HC_IGNSPACE means save all lines that do not start with a space.
 153    Value & HC_IGNDUPS means save all lines that do not match the last
 154    line saved.
 155    Value & HC_ERASEDUPS means to remove all other matching lines from the
 156    history list before saving the latest line. */
 157 int history_control;
 158
 159 /* Set to 1 if the last command was added to the history list successfully
 160    as a separate history entry; set to 0 if the line was ignored or added
 161    to a previous entry as part of command-oriented-history processing. */
 162 int hist_last_line_added;
 163
 164 /* Set to 1 if builtins/history.def:push_history added the last history
 165    entry. */
 166 int hist_last_line_pushed;
 167
 168 #if defined (READLINE)
 169 /* If non-zero, and readline is being used, the user is offered the
 170    chance to re-edit a failed history expansion. */
 171 int history_reediting;
 172
 173 /* If non-zero, and readline is being used, don't directly execute a
 174    line with history substitution.  Reload it into the editing buffer
 175    instead and let the user further edit and confirm with a newline. */
 176 int hist_verify;
 177
 178 #endif /* READLINE */
 179
 180 /* Non-zero means to not save function definitions in the history list. */
 181 int dont_save_function_defs;
 182
 183 /* Variables declared in other files used here. */
 184 extern int current_command_line_count;
 185
 186 extern struct dstack dstack;
 187 extern int parser_state;
 188
 189 static int bash_history_inhibit_expansion __P((char *, int));
 190 #if defined (READLINE)
 191 static void re_edit __P((char *));
 192 #endif
 193 static int history_expansion_p __P((char *));
 194 static int shell_comment __P((char *));
 195 static int should_expand __P((char *));
 196 static HIST_ENTRY *last_history_entry __P((void));
 197 static char *expand_histignore_pattern __P((char *));
 198 static int history_should_ignore __P((char *));
 199
 200 /* Is the history expansion starting at string[i] one that should not
 201    be expanded? */
 202 static int
 203 bash_history_inhibit_expansion (string, i)
 204      char *string;
 205      int i;
 206 {
 207   /* The shell uses ! as a pattern negation character in globbing [...]
 208      expressions, so let those pass without expansion. */
 209   if (i > 0 && (string[i - 1] == '[') && member (']', string + i + 1))
 210     return (1);
 211   /* The shell uses ! as the indirect expansion character, so let those
 212      expansions pass as well. */
 213   else if (i > 1 && string[i - 1] == '{' && string[i - 2] == '$' &&
 214              member ('}', string + i + 1))
 215     return (1);
 216   /* The shell uses $! as a defined parameter expansion. */
 217   else if (i > 1 && string[i - 1] == '$' && string[i] == '!')
 218     return (1);
 219 #if defined (EXTENDED_GLOB)
 220   else if (extended_glob && i > 1 && string[i+1] == '(' && member (')', string + i + 2))
 221     return (1);
 222 #endif
 223   else
 224     return (0);
 225 }
 226
 227 void
 228 bash_initialize_history ()
 229 {
 230   history_quotes_inhibit_expansion = 1;
 231   history_search_delimiter_chars = ";&()|<>";
 232   history_inhibit_expansion_function = bash_history_inhibit_expansion;
 233 #if defined (BANG_HISTORY)
 234   sv_histchars ("histchars");
 235 #endif
 236 }
 237
 238 void
 239 bash_history_reinit (interact)
 240      int interact;
 241 {
 242 #if defined (BANG_HISTORY)
 243   history_expansion = interact != 0;
 244   history_expansion_inhibited = 1;
 245 #endif
 246   remember_on_history = enable_history_list = interact != 0;
 247   history_inhibit_expansion_function = bash_history_inhibit_expansion;
 248 }
 249
 250 void
 251 bash_history_disable ()
 252 {
 253   remember_on_history = 0;
 254 #if defined (BANG_HISTORY)
 255   history_expansion_inhibited = 1;
 256 #endif
 257 }
 258
 259 void
 260 bash_history_enable ()
 261 {
 262   remember_on_history = 1;
 263 #if defined (BANG_HISTORY)
 264   history_expansion_inhibited = 0;
 265 #endif
 266   history_inhibit_expansion_function = bash_history_inhibit_expansion;
 267   sv_history_control ("HISTCONTROL");
 268   sv_histignore ("HISTIGNORE");
 269 }
 270
 271 /* Load the history list from the history file. */
 272 void
 273 load_history ()
 274 {
 275   char *hf;
 276
 277   /* Truncate history file for interactive shells which desire it.
 278      Note that the history file is automatically truncated to the
 279      size of HISTSIZE if the user does not explicitly set the size
 280      differently. */
 281   set_if_not ("HISTSIZE", "500");
 282   sv_histsize ("HISTSIZE");
 283
 284   set_if_not ("HISTFILESIZE", get_string_value ("HISTSIZE"));
 285   sv_histsize ("HISTFILESIZE");
 286
 287   /* Read the history in HISTFILE into the history list. */
 288   hf = get_string_value ("HISTFILE");
 289
 290   if (hf && *hf && file_exists (hf))
 291     {
 292       read_history (hf);
 293       using_history ();
 294       history_lines_in_file = where_history ();
 295     }
 296 }
 297
 298 void
 299 bash_clear_history ()
 300 {
 301   clear_history ();
 302   history_lines_this_session = 0;
 303 }
 304
 305 /* Delete and free the history list entry at offset I. */
 306 int
 307 bash_delete_histent (i)
 308      int i;
 309 {
 310   HIST_ENTRY *discard;
 311
 312   discard = remove_history (i);
 313   if (discard)
 314     free_history_entry (discard);
 315   history_lines_this_session--;
 316
 317   return 1;
 318 }
 319
 320 int
 321 bash_delete_last_history ()
 322 {
 323   register int i;
 324   HIST_ENTRY **hlist, *histent;
 325   int r;
 326
 327   hlist = history_list ();
 328   if (hlist == NULL)
 329     return 0;
 330
 331   for (i = 0; hlist[i]; i++)
 332     ;
 333   i--;
 334
 335   /* History_get () takes a parameter that must be offset by history_base. */
 336   histent = history_get (history_base + i);     /* Don't free this */
 337   if (histent == NULL)
 338     return 0;
 339
 340   r = bash_delete_histent (i);
 341
 342   if (where_history () > history_length)
 343     history_set_pos (history_length);
 344
 345   return r;
 346 }
 347
 348 #ifdef INCLUDE_UNUSED
 349 /* Write the existing history out to the history file. */
 350 void
 351 save_history ()
 352 {
 353   char *hf;
 354
 355   hf = get_string_value ("HISTFILE");
 356   if (hf && *hf && file_exists (hf))
 357     {
 358       /* Append only the lines that occurred this session to
 359          the history file. */
 360       using_history ();
 361
 362       if (history_lines_this_session <= where_history () || force_append_history)
 363         append_history (history_lines_this_session, hf);
 364       else
 365         write_history (hf);
 366       sv_histsize ("HISTFILESIZE");
 367     }
 368 }
 369 #endif
 370
 371 int
 372 maybe_append_history (filename)
 373      char *filename;
 374 {
 375   int fd, result;
 376   struct stat buf;
 377
 378   result = EXECUTION_SUCCESS;
 379   /* XXX - why isn't this <= where_history() ? */
 380   if (history_lines_this_session && (history_lines_this_session <= where_history ()))
 381     {
 382       /* If the filename was supplied, then create it if necessary. */
 383       if (stat (filename, &buf) == -1 && errno == ENOENT)
 384         {
 385           fd = open (filename, O_WRONLY|O_CREAT, 0600);
 386           if (fd < 0)
 387             {
 388               builtin_error (_("%s: cannot create: %s"), filename, strerror (errno));
 389               return (EXECUTION_FAILURE);
 390             }
 391           close (fd);
 392         }
 393       result = append_history (history_lines_this_session, filename);
 394       history_lines_in_file += history_lines_this_session;
 395       history_lines_this_session = 0;
 396     }
 397   return (result);
 398 }
 399
 400 /* If this is an interactive shell, then append the lines executed
 401    this session to the history file. */
 402 int
 403 maybe_save_shell_history ()
 404 {
 405   int result;
 406   char *hf;
 407
 408   result = 0;
 409   if (history_lines_this_session)
 410     {
 411       hf = get_string_value ("HISTFILE");
 412
 413       if (hf && *hf)
 414         {
 415           /* If the file doesn't exist, then create it. */
 416           if (file_exists (hf) == 0)
 417             {
 418               int file;
 419               file = open (hf, O_CREAT | O_TRUNC | O_WRONLY, 0600);
 420               if (file != -1)
 421                 close (file);
 422             }
 423
 424           /* Now actually append the lines if the history hasn't been
 425              stifled.  If the history has been stifled, rewrite the
 426              history file. */
 427           using_history ();
 428           if (history_lines_this_session <= where_history () || force_append_history)
 429             {
 430               result = append_history (history_lines_this_session, hf);
 431               history_lines_in_file += history_lines_this_session;
 432             }
 433           else
 434             {
 435               result = write_history (hf);
 436               history_lines_in_file = history_lines_this_session;
 437             }
 438           history_lines_this_session = 0;
 439
 440           sv_histsize ("HISTFILESIZE");
 441         }
 442     }
 443   return (result);
 444 }
 445
 446 #if defined (READLINE)
 447 /* Tell readline () that we have some text for it to edit. */
 448 static void
 449 re_edit (text)
 450      char *text;
 451 {
 452   if (bash_input.type == st_stdin)
 453     bash_re_edit (text);
 454 }
 455 #endif /* READLINE */
 456
 457 /* Return 1 if this line needs history expansion. */
 458 static int
 459 history_expansion_p (line)
 460      char *line;
 461 {
 462   register char *s;
 463
 464   for (s = line; *s; s++)
 465     if (*s == history_expansion_char || *s == history_subst_char)
 466       return 1;
 467   return 0;
 468 }
 469
 470 /* Do pre-processing on LINE.  If PRINT_CHANGES is non-zero, then
 471    print the results of expanding the line if there were any changes.
 472    If there is an error, return NULL, otherwise the expanded line is
 473    returned.  If ADDIT is non-zero the line is added to the history
 474    list after history expansion.  ADDIT is just a suggestion;
 475    REMEMBER_ON_HISTORY can veto, and does.
 476    Right now this does history expansion. */
 477 char *
 478 pre_process_line (line, print_changes, addit)
 479      char *line;
 480      int print_changes, addit;
 481 {
 482   char *history_value;
 483   char *return_value;
 484   int expanded;
 485
 486   return_value = line;
 487   expanded = 0;
 488
 489 #  if defined (BANG_HISTORY)
 490   /* History expand the line.  If this results in no errors, then
 491      add that line to the history if ADDIT is non-zero. */
 492   if (!history_expansion_inhibited && history_expansion && history_expansion_p (line))
 493     {
 494       expanded = history_expand (line, &history_value);
 495
 496       if (expanded)
 497         {
 498           if (print_changes)
 499             {
 500               if (expanded < 0)
 501                 internal_error ("%s", history_value);
 502 #if defined (READLINE)
 503               else if (hist_verify == 0 || expanded == 2)
 504 #else
 505               else
 506 #endif
 507                 fprintf (stderr, "%s\n", history_value);
 508             }
 509
 510           /* If there was an error, return NULL. */
 511           if (expanded < 0 || expanded == 2)    /* 2 == print only */
 512             {
 513 #    if defined (READLINE)
 514               if (expanded == 2 && rl_dispatching == 0 && *history_value)
 515 #    else
 516               if (expanded == 2 && *history_value)
 517 #    endif /* !READLINE */
 518                 maybe_add_history (history_value);
 519
 520               free (history_value);
 521
 522 #    if defined (READLINE)
 523               /* New hack.  We can allow the user to edit the
 524                  failed history expansion. */
 525               if (history_reediting && expanded < 0 && rl_done)
 526                 re_edit (line);
 527 #    endif /* READLINE */
 528               return ((char *)NULL);
 529             }
 530
 531 #    if defined (READLINE)
 532           if (hist_verify && expanded == 1)
 533             {
 534               re_edit (history_value);
 535               return ((char *)NULL);
 536             }
 537 #    endif
 538         }
 539
 540       /* Let other expansions know that return_value can be free'ed,
 541          and that a line has been added to the history list.  Note
 542          that we only add lines that have something in them. */
 543       expanded = 1;
 544       return_value = history_value;
 545     }
 546 #  endif /* BANG_HISTORY */
 547
 548   if (addit && remember_on_history && *return_value)
 549     maybe_add_history (return_value);
 550
 551 #if 0
 552   if (expanded == 0)
 553     return_value = savestring (line);
 554 #endif
 555
 556   return (return_value);
 557 }
 558
 559 /* Return 1 if the first non-whitespace character in LINE is a `#', indicating
 560  * that the line is a shell comment. */
 561 static int
 562 shell_comment (line)
 563      char *line;
 564 {
 565   char *p;
 566
 567   for (p = line; p && *p && whitespace (*p); p++)
 568     ;
 569   return (p && *p == '#');
 570 }
 571
 572 #ifdef INCLUDE_UNUSED
 573 /* Remove shell comments from LINE.  A `#' and anything after it is a comment.
 574    This isn't really useful yet, since it doesn't handle quoting. */
 575 static char *
 576 filter_comments (line)
 577      char *line;
 578 {
 579   char *p;
 580
 581   for (p = line; p && *p && *p != '#'; p++)
 582     ;
 583   if (p && *p == '#')
 584     *p = '\0';
 585   return (line);
 586 }
 587 #endif
 588
 589 /* Check LINE against what HISTCONTROL says to do.  Returns 1 if the line
 590    should be saved; 0 if it should be discarded. */
 591 static int
 592 check_history_control (line)
 593      char *line;
 594 {
 595   HIST_ENTRY *temp;
 596   int r;
 597
 598   if (history_control == 0)
 599     return 1;
 600
 601   /* ignorespace or ignoreboth */
 602   if ((history_control & HC_IGNSPACE) && *line == ' ')
 603     return 0;
 604
 605   /* ignoredups or ignoreboth */
 606   if (history_control & HC_IGNDUPS)
 607     {
 608       using_history ();
 609       temp = previous_history ();
 610
 611       r = (temp == 0 || STREQ (temp->line, line) == 0);
 612
 613       using_history ();
 614
 615       if (r == 0)
 616         return r;
 617     }
 618
 619   return 1;
 620 }
 621
 622 /* Remove all entries matching LINE from the history list.  Triggered when
 623    HISTCONTROL includes `erasedups'. */
 624 static void
 625 hc_erasedups (line)
 626      char *line;
 627 {
 628   HIST_ENTRY *temp;
 629   int r;
 630
 631   using_history ();
 632   while (temp = previous_history ())
 633     {
 634       if (STREQ (temp->line, line))
 635         {
 636           r = where_history ();
 637           remove_history (r);
 638         }
 639     }
 640   using_history ();
 641 }
 642
 643 /* Add LINE to the history list, handling possibly multi-line compound
 644    commands.  We note whether or not we save the first line of each command
 645    (which is usually the entire command and history entry), and don't add
 646    the second and subsequent lines of a multi-line compound command if we
 647    didn't save the first line.  We don't usually save shell comment lines in
 648    compound commands in the history, because they could have the effect of
 649    commenting out the rest of the command when the entire command is saved as
 650    a single history entry (when COMMAND_ORIENTED_HISTORY is enabled).  If
 651    LITERAL_HISTORY is set, we're saving lines in the history with embedded
 652    newlines, so it's OK to save comment lines.  We also make sure to save
 653    multiple-line quoted strings or other constructs. */
 654 void
 655 maybe_add_history (line)
 656      char *line;
 657 {
 658   hist_last_line_added = 0;
 659
 660   /* Don't use the value of history_control to affect the second
 661      and subsequent lines of a multi-line command (old code did
 662      this only when command_oriented_history is enabled). */
 663   if (current_command_line_count > 1)
 664     {
 665       if (current_command_first_line_saved &&
 666           (literal_history || dstack.delimiter_depth != 0 || shell_comment (line) == 0))
 667         bash_add_history (line);
 668       return;
 669     }
 670
 671   /* This is the first line of a (possible multi-line) command.  Note whether
 672      or not we should save the first line and remember it. */
 673   current_command_first_line_saved = check_add_history (line, 0);
 674 }
 675
 676 /* Just check LINE against HISTCONTROL and HISTIGNORE and add it to the
 677    history if it's OK.  Used by `history -s' as well as maybe_add_history().
 678    Returns 1 if the line was saved in the history, 0 otherwise. */
 679 int
 680 check_add_history (line, force)
 681      char *line;
 682      int force;
 683 {
 684   if (check_history_control (line) && history_should_ignore (line) == 0)
 685     {
 686       /* We're committed to saving the line.  If the user has requested it,
 687          remove other matching lines from the history. */
 688       if (history_control & HC_ERASEDUPS)
 689         hc_erasedups (line);
 690
 691       if (force)
 692         {
 693           really_add_history (line);
 694           using_history ();
 695         }
 696       else
 697         bash_add_history (line);
 698       return 1;
 699     }
 700   return 0;
 701 }
 702
 703 #if defined (SYSLOG_HISTORY)
 704 #define SYSLOG_MAXLEN 600
 705
 706 void
 707 bash_syslog_history (line)
 708      const char *line;
 709 {
 710   char trunc[SYSLOG_MAXLEN];
 711
 712   if (strlen(line) < SYSLOG_MAXLEN)
 713     syslog (SYSLOG_FACILITY|SYSLOG_LEVEL, "HISTORY: PID=%d UID=%d %s", getpid(), current_user.uid, line);
 714   else
 715     {
 716       strncpy (trunc, line, SYSLOG_MAXLEN);
 717       trunc[SYSLOG_MAXLEN - 1] = '\0';
 718       syslog (SYSLOG_FACILITY|SYSLOG_LEVEL, "HISTORY (TRUNCATED): PID=%d UID=%d %s", getpid(), current_user.uid, trunc);
 719     }
 720 }
 721 #endif
 722
 723 /* Add a line to the history list.
 724    The variable COMMAND_ORIENTED_HISTORY controls the style of history
 725    remembering;  when non-zero, and LINE is not the first line of a
 726    complete parser construct, append LINE to the last history line instead
 727    of adding it as a new line. */
 728 void
 729 bash_add_history (line)
 730      char *line;
 731 {
 732   int add_it, offset, curlen;
 733   HIST_ENTRY *current, *old;
 734   char *chars_to_add, *new_line;
 735
 736   add_it = 1;
 737   if (command_oriented_history && current_command_line_count > 1)
 738     {
 739       chars_to_add = literal_history ? "\n" : history_delimiting_chars (line);
 740
 741       using_history ();
 742       current = previous_history ();
 743
 744       if (current)
 745         {
 746           /* If the previous line ended with an escaped newline (escaped
 747              with backslash, but otherwise unquoted), then remove the quoted
 748              newline, since that is what happens when the line is parsed. */
 749           curlen = strlen (current->line);
 750
 751           if (dstack.delimiter_depth == 0 && current->line[curlen - 1] == '\\' &&
 752               current->line[curlen - 2] != '\\')
 753             {
 754               current->line[curlen - 1] = '\0';
 755               curlen--;
 756               chars_to_add = "";
 757             }
 758
 759           /* If we're not in some kind of quoted construct, the current history
 760              entry ends with a newline, and we're going to add a semicolon,
 761              don't.  In some cases, it results in a syntax error (e.g., before
 762              a close brace), and it should not be needed. */
 763           if (dstack.delimiter_depth == 0 && current->line[curlen - 1] == '\n' && *chars_to_add == ';')
 764             chars_to_add++;
 765
 766           new_line = (char *)xmalloc (1
 767                                       + curlen
 768                                       + strlen (line)
 769                                       + strlen (chars_to_add));
 770           sprintf (new_line, "%s%s%s", current->line, chars_to_add, line);
 771           offset = where_history ();
 772           old = replace_history_entry (offset, new_line, current->data);
 773           free (new_line);
 774
 775           if (old)
 776             free_history_entry (old);
 777
 778           add_it = 0;
 779         }
 780     }
 781
 782   if (add_it)
 783     really_add_history (line);
 784
 785 #if defined (SYSLOG_HISTORY)
 786   bash_syslog_history (line);
 787 #endif
 788
 789   using_history ();
 790 }
 791
 792 static void
 793 really_add_history (line)
 794      char *line;
 795 {
 796   hist_last_line_added = 1;
 797   hist_last_line_pushed = 0;
 798   add_history (line);
 799   history_lines_this_session++;
 800 }
 801
 802 int
 803 history_number ()
 804 {
 805   using_history ();
 806   return (remember_on_history ? history_base + where_history () : 1);
 807 }
 808
 809 static int
 810 should_expand (s)
 811      char *s;
 812 {
 813   char *p;
 814
 815   for (p = s; p && *p; p++)
 816     {
 817       if (*p == '\\')
 818         p++;
 819       else if (*p == '&')
 820         return 1;
 821     }
 822   return 0;
 823 }
 824
 825 static int
 826 histignore_item_func (ign)
 827      struct ign *ign;
 828 {
 829   if (should_expand (ign->val))
 830     ign->flags |= HIGN_EXPAND;
 831   return (0);
 832 }
 833
 834 void
 835 setup_history_ignore (varname)
 836      char *varname;
 837 {
 838   setup_ignore_patterns (&histignore);
 839 }
 840
 841 static HIST_ENTRY *
 842 last_history_entry ()
 843 {
 844   HIST_ENTRY *he;
 845
 846   using_history ();
 847   he = previous_history ();
 848   using_history ();
 849   return he;
 850 }
 851
 852 char *
 853 last_history_line ()
 854 {
 855   HIST_ENTRY *he;
 856
 857   he = last_history_entry ();
 858   if (he == 0)
 859     return ((char *)NULL);
 860   return he->line;
 861 }
 862
 863 static char *
 864 expand_histignore_pattern (pat)
 865      char *pat;
 866 {
 867   HIST_ENTRY *phe;
 868   char *ret;
 869
 870   phe = last_history_entry ();
 871
 872   if (phe == (HIST_ENTRY *)0)
 873     return (savestring (pat));
 874
 875   ret = strcreplace (pat, '&', phe->line, 1);
 876
 877   return ret;
 878 }
 879
 880 /* Return 1 if we should not put LINE into the history according to the
 881    patterns in HISTIGNORE. */
 882 static int
 883 history_should_ignore (line)
 884      char *line;
 885 {
 886   register int i, match;
 887   char *npat;
 888
 889   if (histignore.num_ignores == 0)
 890     return 0;
 891
 892   for (i = match = 0; i < histignore.num_ignores; i++)
 893     {
 894       if (histignore.ignores[i].flags & HIGN_EXPAND)
 895         npat = expand_histignore_pattern (histignore.ignores[i].val);
 896       else
 897         npat = histignore.ignores[i].val;
 898
 899       match = strmatch (npat, line, FNMATCH_EXTFLAG) != FNM_NOMATCH;
 900
 901       if (histignore.ignores[i].flags & HIGN_EXPAND)
 902         free (npat);
 903
 904       if (match)
 905         break;
 906     }
 907
 908   return match;
 909 }
 910 #endif /* HISTORY */