/* History.c -- standalone history library */ /* Copyright (C) 1989 Free Software Foundation, Inc. This file contains the GNU History Library (the Library), a set of routines for managing the text of previously typed lines. The 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 1, or (at your option) any later version. The 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, 675 Mass Ave, Cambridge, MA 02139, USA. */ /* The goal is to make the implementation transparent, so that you don't have to know what data types are used, just what functions you can call. I think I have done that. */ /* Remove these declarations when we have a complete libgnu.a. */ #if !defined (STATIC_MALLOC) extern char *xmalloc (), *xrealloc (); #else static char *xmalloc (), *xrealloc (); #endif #include "sysdep.h" #include #include #include #include #include #if defined (__GNUC__) # define alloca __builtin_alloca #else # if defined (sparc) || defined (HAVE_ALLOCA_H) # include # endif /* sparc || HAVE_ALLOCA_H */ #endif /* !__GNU_C__ */ #include "history.h" #ifndef savestring #define savestring(x) (char *)strcpy (xmalloc (1 + strlen (x)), (x)) #endif #ifndef whitespace #define whitespace(c) (((c) == ' ') || ((c) == '\t')) #endif #ifndef digit #define digit(c) ((c) >= '0' && (c) <= '9') #endif #ifndef member #define member(c, s) ((c) ? index ((s), (c)) : 0) #endif /* **************************************************************** */ /* */ /* History Functions */ /* */ /* **************************************************************** */ /* An array of HIST_ENTRY. This is where we store the history. */ static HIST_ENTRY **the_history = (HIST_ENTRY **)NULL; /* Non-zero means that we have enforced a limit on the amount of history that we save. */ int history_stifled = 0; /* If HISTORY_STIFLED is non-zero, then this is the maximum number of entries to remember. */ int max_input_history; /* The current location of the interactive history pointer. Just makes life easier for outside callers. */ static int history_offset = 0; /* The number of strings currently stored in the input_history list. */ int history_length = 0; /* The current number of slots allocated to the input_history. */ static int history_size = 0; /* The number of slots to increase the_history by. */ #define DEFAULT_HISTORY_GROW_SIZE 50 /* The character that represents the start of a history expansion request. This is usually `!'. */ char history_expansion_char = '!'; /* The character that invokes word substitution if found at the start of a line. This is usually `^'. */ char history_subst_char = '^'; /* During tokenization, if this character is seen as the first character of a word, then it, and all subsequent characters upto a newline are ignored. For a Bourne shell, this should be '#'. Bash special cases the interactive comment character to not be a comment delimiter. */ char history_comment_char = '\0'; /* The list of characters which inhibit the expansion of text if found immediately following history_expansion_char. */ char *history_no_expand_chars = " \t\n\r="; /* The logical `base' of the history array. It defaults to 1. */ int history_base = 1; /* Begin a session in which the history functions might be used. This initializes interactive variables. */ void using_history () { history_offset = history_length; } /* Return the number of bytes that the primary history entries are using. This just adds up the lengths of the_history->lines. */ int history_total_bytes () { register int i, result; result = 0; for (i = 0; the_history && the_history[i]; i++) result += strlen (the_history[i]->line); return (result); } /* Place STRING at the end of the history list. The data field is set to NULL. */ void add_history (string) char *string; { HIST_ENTRY *temp; if (history_stifled && (history_length == max_input_history)) { register int i; /* If the history is stifled, and history_length is zero, and it equals max_input_history, we don't save items. */ if (!history_length) return; /* If there is something in the slot, then remove it. */ if (the_history[0]) { free (the_history[0]->line); free (the_history[0]); } for (i = 0; i < history_length; i++) the_history[i] = the_history[i + 1]; history_base++; } else { if (!history_size) { the_history = (HIST_ENTRY **) xmalloc ((history_size = DEFAULT_HISTORY_GROW_SIZE) * sizeof (HIST_ENTRY *)); history_length = 1; } else { if (history_length == (history_size - 1)) { the_history = (HIST_ENTRY **) xrealloc (the_history, ((history_size += DEFAULT_HISTORY_GROW_SIZE) * sizeof (HIST_ENTRY *))); } history_length++; } } temp = (HIST_ENTRY *)xmalloc (sizeof (HIST_ENTRY)); temp->line = savestring (string); temp->data = (char *)NULL; the_history[history_length] = (HIST_ENTRY *)NULL; the_history[history_length - 1] = temp; } /* Make the history entry at WHICH have LINE and DATA. This returns the old entry so you can dispose of the data. In the case of an invalid WHICH, a NULL pointer is returned. */ HIST_ENTRY * replace_history_entry (which, line, data) int which; char *line; char *data; { HIST_ENTRY *temp = (HIST_ENTRY *)xmalloc (sizeof (HIST_ENTRY)); HIST_ENTRY *old_value; if (which >= history_length) return ((HIST_ENTRY *)NULL); old_value = the_history[which]; temp->line = savestring (line); temp->data = data; the_history[which] = temp; return (old_value); } /* Returns the magic number which says what history element we are looking at now. In this implementation, it returns history_offset. */ int where_history () { return (history_offset); } /* Search the history for STRING, starting at history_offset. If DIRECTION < 0, then the search is through previous entries, else through subsequent. If ANCHORED is non-zero, the string must appear at the beginning of a history line, otherwise, the string may appear anywhere in the line. If the string is found, then current_history () is the history entry, and the value of this function is the offset in the line of that history entry that the string was found in. Otherwise, nothing is changed, and a -1 is returned. */ #define ANCHORED_SEARCH 1 #define NON_ANCHORED_SEARCH 0 static int history_search_internal (string, direction, anchored) char *string; int direction, anchored; { register int i = history_offset; register int reverse = (direction < 0); register char *line; register int index; int string_len = strlen (string); /* Take care of trivial cases first. */ if (!history_length || ((i == history_length) && !reverse)) return (-1); if (reverse && (i == history_length)) i--; while (1) { /* Search each line in the history list for STRING. */ /* At limit for direction? */ if ((reverse && i < 0) || (!reverse && i == history_length)) return (-1); line = the_history[i]->line; index = strlen (line); /* If STRING is longer than line, no match. */ if (string_len > index) goto next_line; /* Handle anchored searches first. */ if (anchored == ANCHORED_SEARCH) { if (strncmp (string, line, string_len) == 0) { history_offset = i; return (0); } goto next_line; } /* Do substring search. */ if (reverse) { index -= string_len; while (index >= 0) { if (strncmp (string, line + index, string_len) == 0) { history_offset = i; return (index); } index--; } } else { register int limit = index - string_len + 1; index = 0; while (index < limit) { if (strncmp (string, line + index, string_len) == 0) { history_offset = i; return (index); } index++; } } next_line: if (reverse) i--; else i++; } } /* Do a non-anchored search for STRING through the history in DIRECTION. */ int history_search (string, direction) char *string; int direction; { return (history_search_internal (string, direction, NON_ANCHORED_SEARCH)); } /* Do an anchored search for string through the history in DIRECTION. */ int history_search_prefix (string, direction) char *string; int direction; { return (history_search_internal (string, direction, ANCHORED_SEARCH)); } /* Remove history element WHICH from the history. The removed element is returned to you so you can free the line, data, and containing structure. */ HIST_ENTRY * remove_history (which) int which; { HIST_ENTRY *return_value; if (which >= history_length || !history_length) return_value = (HIST_ENTRY *)NULL; else { register int i; return_value = the_history[which]; for (i = which; i < history_length; i++) the_history[i] = the_history[i + 1]; history_length--; } return (return_value); } /* Stifle the history list, remembering only MAX number of lines. */ void stifle_history (max) int max; { if (history_length > max) { register int i, j; /* This loses because we cannot free the data. */ for (i = 0; i < (history_length - max); i++) { free (the_history[i]->line); free (the_history[i]); } history_base = i; for (j = 0, i = history_length - max; j < max; i++, j++) the_history[j] = the_history[i]; the_history[j] = (HIST_ENTRY *)NULL; history_length = j; } history_stifled = 1; max_input_history = max; } /* Stop stifling the history. This returns the previous amount the history was stifled by. The value is positive if the history was stifled, negative if it wasn't. */ int unstifle_history () { int result = max_input_history; if (history_stifled) { result = - result; history_stifled = 0; } return (result); } /* Return the string that should be used in the place of this filename. This only matters when you don't specify the filename to read_history (), or write_history (). */ static char * history_filename (filename) char *filename; { char *return_val = filename ? savestring (filename) : (char *)NULL; if (!return_val) { char *home = (char *)getenv ("HOME"); if (!home) home = "."; return_val = (char *)xmalloc (2 + strlen (home) + strlen (".history")); sprintf (return_val, "%s/.history", home); } return (return_val); } /* Add the contents of FILENAME to the history list, a line at a time. If FILENAME is NULL, then read from ~/.history. Returns 0 if successful, or errno if not. */ int read_history (filename) char *filename; { return (read_history_range (filename, 0, -1)); } /* Read a range of lines from FILENAME, adding them to the history list. Start reading at the FROM'th line and end at the TO'th. If FROM is zero, start at the beginning. If TO is less than FROM, read until the end of the file. If FILENAME is NULL, then read from ~/.history. Returns 0 if successful, or errno if not. */ int read_history_range (filename, from, to) char *filename; int from, to; { register int line_start, line_end; char *input, *buffer = (char *)NULL; int file, current_line; struct stat finfo; extern int errno; input = history_filename (filename); file = open (input, O_RDONLY, 0666); if ((file < 0) || (stat (input, &finfo) == -1)) goto error_and_exit; buffer = (char *)xmalloc (finfo.st_size + 1); if (read (file, buffer, finfo.st_size) != finfo.st_size) error_and_exit: { if (file >= 0) close (file); if (buffer) free (buffer); return (errno); } close (file); /* Set TO to larger than end of file if negative. */ if (to < 0) to = finfo.st_size; /* Start at beginning of file, work to end. */ line_start = line_end = current_line = 0; /* Skip lines until we are at FROM. */ while (line_start < finfo.st_size && current_line < from) { for (line_end = line_start; line_end < finfo.st_size; line_end++) if (buffer[line_end] == '\n') { current_line++; line_start = line_end + 1; if (current_line == from) break; } } /* If there are lines left to gobble, then gobble them now. */ for (line_end = line_start; line_end < finfo.st_size; line_end++) if (buffer[line_end] == '\n') { buffer[line_end] = '\0'; if (buffer[line_start]) add_history (buffer + line_start); current_line++; if (current_line >= to) break; line_start = line_end + 1; } return (0); } /* Truncate the history file FNAME, leaving only LINES trailing lines. If FNAME is NULL, then use ~/.history. */ history_truncate_file (fname, lines) char *fname; register int lines; { register int i; int file; char *buffer = (char *)NULL, *filename; struct stat finfo; filename = history_filename (fname); if (stat (filename, &finfo) == -1) goto truncate_exit; file = open (filename, O_RDONLY, 0666); if (file == -1) goto truncate_exit; buffer = (char *)xmalloc (finfo.st_size + 1); read (file, buffer, finfo.st_size); close (file); /* Count backwards from the end of buffer until we have passed LINES lines. */ for (i = finfo.st_size; lines && i; i--) { if (buffer[i] == '\n') lines--; } /* If there are fewer lines in the file than we want to truncate to, then we are all done. */ if (!i) goto truncate_exit; /* Otherwise, write from the start of this line until the end of the buffer. */ for (--i; i; i--) if (buffer[i] == '\n') { i++; break; } file = open (filename, O_WRONLY | O_TRUNC | O_CREAT, 0666); if (file == -1) goto truncate_exit; write (file, buffer + i, finfo.st_size - i); close (file); truncate_exit: if (buffer) free (buffer); free (filename); } #define HISTORY_APPEND 0 #define HISTORY_OVERWRITE 1 /* Workhorse function for writing history. Writes NELEMENT entries from the history list to FILENAME. OVERWRITE is non-zero if you wish to replace FILENAME with the entries. */ static int history_do_write (filename, nelements, overwrite) char *filename; int nelements, overwrite; { extern int errno; register int i; char *output = history_filename (filename); int file, mode; char cr = '\n'; if (overwrite) mode = O_WRONLY | O_CREAT | O_TRUNC; else mode = O_WRONLY | O_APPEND; if ((file = open (output, mode, 0666)) == -1) return (errno); if (nelements > history_length) nelements = history_length; for (i = history_length - nelements; i < history_length; i++) { if (write (file, the_history[i]->line, strlen (the_history[i]->line)) < 0) break; if (write (file, &cr, 1) < 0) break; } close (file); return (0); } /* Append NELEMENT entries to FILENAME. The entries appended are from the end of the list minus NELEMENTs up to the end of the list. */ int append_history (nelements, filename) int nelements; char *filename; { return (history_do_write (filename, nelements, HISTORY_APPEND)); } /* Overwrite FILENAME with the current history. If FILENAME is NULL, then write the history list to ~/.history. Values returned are as in read_history ().*/ int write_history (filename) char *filename; { return (history_do_write (filename, history_length, HISTORY_OVERWRITE)); } /* Return the history entry at the current position, as determined by history_offset. If there is no entry there, return a NULL pointer. */ HIST_ENTRY * current_history () { if ((history_offset == history_length) || !the_history) return ((HIST_ENTRY *)NULL); else return (the_history[history_offset]); } /* Back up history_offset to the previous history entry, and return a pointer to that entry. If there is no previous entry then return a NULL pointer. */ HIST_ENTRY * previous_history () { if (!history_offset) return ((HIST_ENTRY *)NULL); else return (the_history[--history_offset]); } /* Move history_offset forward to the next history entry, and return a pointer to that entry. If there is no next entry then return a NULL pointer. */ HIST_ENTRY * next_history () { if (history_offset == history_length) return ((HIST_ENTRY *)NULL); else return (the_history[++history_offset]); } /* Return the current history array. The caller has to be carefull, since this is the actual array of data, and could be bashed or made corrupt easily. The array is terminated with a NULL pointer. */ HIST_ENTRY ** history_list () { return (the_history); } /* Return the history entry which is logically at OFFSET in the history array. OFFSET is relative to history_base. */ HIST_ENTRY * history_get (offset) int offset; { int index = offset - history_base; if (index >= history_length || index < 0 || !the_history) return ((HIST_ENTRY *)NULL); return (the_history[index]); } /* Search for STRING in the history list. DIR is < 0 for searching backwards. POS is an absolute index into the history list at which point to begin searching. */ int history_search_pos (string, dir, pos) char *string; int dir, pos; { int ret, old = where_history (); history_set_pos (pos); if (history_search (string, dir) == -1) { history_set_pos (old); return (-1); } ret = where_history (); history_set_pos (old); return ret; } /* Make the current history item be the one at POS, an absolute index. Returns zero if POS is out of range, else non-zero. */ int history_set_pos (pos) int pos; { if (pos > history_length || pos < 0 || !the_history) return (0); history_offset = pos; return (1); } /* **************************************************************** */ /* */ /* History Expansion */ /* */ /* **************************************************************** */ /* Hairy history expansion on text, not tokens. This is of general use, and thus belongs in this library. */ /* The last string searched for in a !?string? search. */ static char *search_string = (char *)NULL; /* Return the event specified at TEXT + OFFSET modifying OFFSET to point to after the event specifier. Just a pointer to the history line is returned; NULL is returned in the event of a bad specifier. You pass STRING with *INDEX equal to the history_expansion_char that begins this specification. DELIMITING_QUOTE is a character that is allowed to end the string specification for what to search for in addition to the normal characters `:', ` ', `\t', `\n', and sometimes `?'. So you might call this function like: line = get_history_event ("!echo:p", &index, 0); */ char * get_history_event (string, caller_index, delimiting_quote) char *string; int *caller_index; int delimiting_quote; { register int i = *caller_index; int which, sign = 1; HIST_ENTRY *entry; /* The event can be specified in a number of ways. !! the previous command !n command line N !-n current command-line minus N !str the most recent command starting with STR !?str[?] the most recent command containing STR All values N are determined via HISTORY_BASE. */ if (string[i] != history_expansion_char) return ((char *)NULL); /* Move on to the specification. */ i++; /* Handle !! case. */ if (string[i] == history_expansion_char) { i++; which = history_base + (history_length - 1); *caller_index = i; goto get_which; } /* Hack case of numeric line specification. */ read_which: if (string[i] == '-') { sign = -1; i++; } if (digit (string[i])) { int start = i; /* Get the extent of the digits. */ for (; digit (string[i]); i++); /* Get the digit value. */ sscanf (string + start, "%d", &which); *caller_index = i; if (sign < 0) which = (history_length + history_base) - which; get_which: if (entry = history_get (which)) return (entry->line); return ((char *)NULL); } /* This must be something to search for. If the spec begins with a '?', then the string may be anywhere on the line. Otherwise, the string must be found at the start of a line. */ { int index; char *temp; int substring_okay = 0; if (string[i] == '?') { substring_okay++; i++; } for (index = i; string[i]; i++) if (whitespace (string[i]) || string[i] == '\n' || string[i] == ':' || (substring_okay && string[i] == '?') || string[i] == delimiting_quote) break; temp = (char *)alloca (1 + (i - index)); strncpy (temp, &string[index], (i - index)); temp[i - index] = '\0'; if (string[i] == '?') i++; *caller_index = i; search_again: index = history_search_internal (temp, -1, substring_okay ? NON_ANCHORED_SEARCH : ANCHORED_SEARCH); if (index < 0) search_lost: { history_offset = history_length; return ((char *)NULL); } if (index == 0) { search_won: entry = current_history (); history_offset = history_length; /* If this was a substring search, then remember the string that we matched for word substitution. */ if (substring_okay) { if (search_string) free (search_string); search_string = savestring (temp); } return (entry->line); } if (history_offset) history_offset--; else goto search_lost; goto search_again; } } /* Expand the string STRING, placing the result into OUTPUT, a pointer to a string. Returns: 0) If no expansions took place (or, if the only change in the text was the de-slashifying of the history expansion character) 1) If expansions did take place -1) If there was an error in expansion. If an error ocurred in expansion, then OUTPUT contains a descriptive error message. */ int history_expand (string, output) char *string; char **output; { register int j, l = strlen (string); int i, word_spec_error = 0; int cc, modified = 0; char *word_spec, *event; int starting_index, only_printing = 0, substitute_globally = 0; char *get_history_word_specifier (), *rindex (); /* The output string, and its length. */ int len = 0; char *result = (char *)NULL; /* Used in add_string; */ char *temp, tt[2], tbl[3]; /* Prepare the buffer for printing error messages. */ result = (char *)xmalloc (len = 255); result[0] = tt[1] = tbl[2] = '\0'; tbl[0] = '\\'; tbl[1] = history_expansion_char; /* Grovel the string. Only backslash can quote the history escape character. We also handle arg specifiers. */ /* Before we grovel forever, see if the history_expansion_char appears anywhere within the text. */ /* The quick substitution character is a history expansion all right. That is to say, "^this^that^" is equivalent to "!!:s^this^that^", and in fact, that is the substitution that we do. */ if (string[0] == history_subst_char) { char *format_string = (char *)alloca (10 + strlen (string)); sprintf (format_string, "%c%c:s%s", history_expansion_char, history_expansion_char, string); string = format_string; l += 4; goto grovel; } /* If not quick substitution, still maybe have to do expansion. */ /* `!' followed by one of the characters in history_no_expand_chars is NOT an expansion. */ for (i = 0; string[i]; i++) if (string[i] == history_expansion_char) if (!string[i + 1] || member (string[i + 1], history_no_expand_chars)) continue; else goto grovel; free (result); *output = savestring (string); return (0); grovel: for (i = j = 0; i < l; i++) { int tchar = string[i]; if (tchar == history_expansion_char) tchar = -3; switch (tchar) { case '\\': if (string[i + 1] == history_expansion_char) { i++; temp = tbl; goto do_add; } else goto add_char; /* case history_expansion_char: */ case -3: starting_index = i + 1; cc = string[i + 1]; /* If the history_expansion_char is followed by one of the characters in history_no_expand_chars, then it is not a candidate for expansion of any kind. */ if (member (cc, history_no_expand_chars)) goto add_char; /* There is something that is listed as a `word specifier' in csh documentation which means `the expanded text to this point'. That is not a word specifier, it is an event specifier. */ if (cc == '#') goto hack_pound_sign; /* If it is followed by something that starts a word specifier, then !! is implied as the event specifier. */ if (member (cc, ":$*%^")) { char fake_s[3]; int fake_i = 0; i++; fake_s[0] = fake_s[1] = history_expansion_char; fake_s[2] = '\0'; event = get_history_event (fake_s, &fake_i, 0); } else { int quoted_search_delimiter = 0; /* If the character before this `!' is a double or single quote, then this expansion takes place inside of the quoted string. If we have to search for some text ("!foo"), allow the delimiter to end the search string. */ if (i && (string[i - 1] == '\'' || string[i - 1] == '"')) quoted_search_delimiter = string[i - 1]; event = get_history_event (string, &i, quoted_search_delimiter); } if (!event) event_not_found: { int l = 1 + (i - starting_index); temp = (char *)alloca (1 + l); strncpy (temp, string + starting_index, l); temp[l - 1] = 0; sprintf (result, "%s: %s.", temp, word_spec_error ? "Bad word specifier" : "Event not found"); error_exit: *output = result; return (-1); } /* If a word specifier is found, then do what that requires. */ starting_index = i; word_spec = get_history_word_specifier (string, event, &i); /* There is no such thing as a `malformed word specifier'. However, it is possible for a specifier that has no match. In that case, we complain. */ if (word_spec == (char *)-1) bad_word_spec: { word_spec_error++; goto event_not_found; } /* If no word specifier, than the thing of interest was the event. */ if (!word_spec) temp = event; else { temp = (char *)alloca (1 + strlen (word_spec)); strcpy (temp, word_spec); free (word_spec); } /* Perhaps there are other modifiers involved. Do what they say. */ hack_specials: if (string[i] == ':') { char *tstr; switch (string[i + 1]) { /* :p means make this the last executed line. So we return an error state after adding this line to the history. */ case 'p': only_printing++; goto next_special; /* :t discards all but the last part of the pathname. */ case 't': tstr = rindex (temp, '/'); if (tstr) temp = ++tstr; goto next_special; /* :h discards the last part of a pathname. */ case 'h': tstr = rindex (temp, '/'); if (tstr) *tstr = '\0'; goto next_special; /* :r discards the suffix. */ case 'r': tstr = rindex (temp, '.'); if (tstr) *tstr = '\0'; goto next_special; /* :e discards everything but the suffix. */ case 'e': tstr = rindex (temp, '.'); if (tstr) temp = tstr; goto next_special; /* :s/this/that substitutes `this' for `that'. */ /* :gs/this/that substitutes `this' for `that' globally. */ case 'g': if (string[i + 2] == 's') { i++; substitute_globally = 1; goto substitute; } else case 's': substitute: { char *this, *that, *new_event; int delimiter = 0; int si, l_this, l_that, l_temp = strlen (temp); if (i + 2 < strlen (string)) delimiter = string[i + 2]; if (!delimiter) break; i += 3; /* Get THIS. */ for (si = i; string[si] && string[si] != delimiter; si++); l_this = (si - i); this = (char *)alloca (1 + l_this); strncpy (this, string + i, l_this); this[l_this] = '\0'; i = si; if (string[si]) i++; /* Get THAT. */ for (si = i; string[si] && string[si] != delimiter; si++); l_that = (si - i); that = (char *)alloca (1 + l_that); strncpy (that, string + i, l_that); that[l_that] = '\0'; i = si; if (string[si]) i++; /* Ignore impossible cases. */ if (l_this > l_temp) goto cant_substitute; /* Find the first occurrence of THIS in TEMP. */ si = 0; for (; (si + l_this) <= l_temp; si++) if (strncmp (temp + si, this, l_this) == 0) { new_event = (char *)alloca (1 + (l_that - l_this) + l_temp); strncpy (new_event, temp, si); strncpy (new_event + si, that, l_that); strncpy (new_event + si + l_that, temp + si + l_this, l_temp - (si + l_this)); new_event[(l_that - l_this) + l_temp] = '\0'; temp = new_event; if (substitute_globally) { si += l_that; l_temp = strlen (temp); substitute_globally++; continue; } goto hack_specials; } cant_substitute: if (substitute_globally > 1) { substitute_globally = 0; goto hack_specials; } goto event_not_found; } /* :# is the line so far. Note that we have to alloca () it since RESULT could be realloc ()'ed below in add_string. */ case '#': hack_pound_sign: if (result) { temp = (char *)alloca (1 + strlen (result)); strcpy (temp, result); } else temp = ""; next_special: i += 2; goto hack_specials; } } /* Believe it or not, we have to back the pointer up by one. */ --i; goto add_string; /* A regular character. Just add it to the output string. */ default: add_char: tt[0] = string[i]; temp = tt; goto do_add; add_string: modified++; do_add: j += strlen (temp); while (j > len) result = (char *)xrealloc (result, (len += 255)); strcpy (result + (j - strlen (temp)), temp); } } *output = result; if (only_printing) { add_history (result); return (-1); } return (modified != 0); } /* Return a consed string which is the word specified in SPEC, and found in FROM. NULL is returned if there is no spec. -1 is returned if the word specified cannot be found. CALLER_INDEX is the offset in SPEC to start looking; it is updated to point to just after the last character parsed. */ char * get_history_word_specifier (spec, from, caller_index) char *spec, *from; int *caller_index; { register int i = *caller_index; int first, last; int expecting_word_spec = 0; char *history_arg_extract (); /* The range of words to return doesn't exist yet. */ first = last = 0; /* If we found a colon, then this *must* be a word specification. If it isn't, then it is an error. */ if (spec[i] == ':') i++, expecting_word_spec++; /* Handle special cases first. */ /* `%' is the word last searched for. */ if (spec[i] == '%') { *caller_index = i + 1; if (search_string) return (savestring (search_string)); else return (savestring ("")); } /* `*' matches all of the arguments, but not the command. */ if (spec[i] == '*') { char *star_result; *caller_index = i + 1; star_result = history_arg_extract (1, '$', from); if (!star_result) star_result = savestring (""); return (star_result); } /* `$' is last arg. */ if (spec[i] == '$') { *caller_index = i + 1; return (history_arg_extract ('$', '$', from)); } /* Try to get FIRST and LAST figured out. */ if (spec[i] == '-' || spec[i] == '^') { first = 1; goto get_last; } get_first: if (digit (spec[i]) && expecting_word_spec) { sscanf (spec + i, "%d", &first); for (; digit (spec[i]); i++); } else return ((char *)NULL); get_last: if (spec[i] == '^') { i++; last = 1; goto get_args; } if (spec[i] != '-') { last = first; goto get_args; } i++; if (digit (spec[i])) { sscanf (spec + i, "%d", &last); for (; digit (spec[i]); i++); } else if (spec[i] == '$') { i++; last = '$'; } get_args: { char *result = (char *)NULL; *caller_index = i; if (last >= first) result = history_arg_extract (first, last, from); if (result) return (result); else return ((char *)-1); } } /* Extract the args specified, starting at FIRST, and ending at LAST. The args are taken from STRING. If either FIRST or LAST is < 0, then make that arg count from the right (subtract from the number of tokens, so that FIRST = -1 means the next to last token on the line). */ char * history_arg_extract (first, last, string) int first, last; char *string; { register int i, len; char *result = (char *)NULL; int size = 0, offset = 0; char **history_tokenize (), **list; if (!(list = history_tokenize (string))) return ((char *)NULL); for (len = 0; list[len]; len++); if (last < 0) last = len + last - 1; if (first < 0) first = len + first - 1; if (last == '$') last = len - 1; if (first == '$') first = len - 1; last++; if (first > len || last > len || first < 0 || last < 0) result = ((char *)NULL); else { for (i = first; i < last; i++) { int l = strlen (list[i]); if (!result) result = (char *)xmalloc ((size = (2 + l))); else result = (char *)xrealloc (result, (size += (2 + l))); strcpy (result + offset, list[i]); offset += l; if (i + 1 < last) { strcpy (result + offset, " "); offset++; } } } for (i = 0; i < len; i++) free (list[i]); free (list); return (result); } #define slashify_in_quotes "\\`\"$" /* Return an array of tokens, much as the shell might. The tokens are parsed out of STRING. */ char ** history_tokenize (string) char *string; { char **result = (char **)NULL; register int i, start, result_index, size; int len; i = result_index = size = 0; /* Get a token, and stuff it into RESULT. The tokens are split exactly where the shell would split them. */ get_token: /* Skip leading whitespace. */ for (; string[i] && whitespace(string[i]); i++); start = i; if (!string[i] || string[i] == history_comment_char) return (result); if (member (string[i], "()\n")) { i++; goto got_token; } if (member (string[i], "<>;&|")) { int peek = string[i + 1]; if (peek == string[i]) { if (peek == '<') { if (string[1 + 2] == '-') i++; i += 2; goto got_token; } if (member (peek, ">:&|")) { i += 2; goto got_token; } } else { if ((peek == '&' && (string[i] == '>' || string[i] == '<')) || ((peek == '>') && (string[i] == '&'))) { i += 2; goto got_token; } } i++; goto got_token; } /* Get word from string + i; */ { int delimiter = 0; if (member (string[i], "\"'`")) delimiter = string[i++]; for (;string[i]; i++) { if (string[i] == '\\') { if (string[i + 1] == '\n') { i++; continue; } else { if (delimiter != '\'') if ((delimiter != '"') || (member (string[i], slashify_in_quotes))) { i++; continue; } } } if (delimiter && string[i] == delimiter) { delimiter = 0; continue; } if (!delimiter && (member (string[i], " \t\n;&()|<>"))) goto got_token; if (!delimiter && member (string[i], "\"'`")) { delimiter = string[i]; continue; } } got_token: len = i - start; if (result_index + 2 >= size) { if (!size) result = (char **)xmalloc ((size = 10) * (sizeof (char *))); else result = (char **)xrealloc (result, ((size += 10) * (sizeof (char *)))); } result[result_index] = (char *)xmalloc (1 + len); strncpy (result[result_index], string + start, len); result[result_index][len] = '\0'; result_index++; result[result_index] = (char *)NULL; } if (string[i]) goto get_token; return (result); } #if defined (STATIC_MALLOC) /* **************************************************************** */ /* */ /* xmalloc and xrealloc () */ /* */ /* **************************************************************** */ static void memory_error_and_abort (); static char * xmalloc (bytes) int bytes; { char *temp = (char *)malloc (bytes); if (!temp) memory_error_and_abort (); return (temp); } static char * xrealloc (pointer, bytes) char *pointer; int bytes; { char *temp; if (!pointer) temp = (char *)xmalloc (bytes); else temp = (char *)realloc (pointer, bytes); if (!temp) memory_error_and_abort (); return (temp); } static void memory_error_and_abort () { fprintf (stderr, "history: Out of virtual memory!\n"); abort (); } #endif /* STATIC_MALLOC */ /* **************************************************************** */ /* */ /* Test Code */ /* */ /* **************************************************************** */ #ifdef TEST main () { char line[1024], *t; int done = 0; line[0] = 0; while (!done) { fprintf (stdout, "history%% "); t = gets (line); if (!t) strcpy (line, "quit"); if (line[0]) { char *expansion; int result; using_history (); result = history_expand (line, &expansion); strcpy (line, expansion); free (expansion); if (result) fprintf (stderr, "%s\n", line); if (result < 0) continue; add_history (line); } if (strcmp (line, "quit") == 0) done = 1; if (strcmp (line, "save") == 0) write_history (0); if (strcmp (line, "read") == 0) read_history (0); if (strcmp (line, "list") == 0) { register HIST_ENTRY **the_list = history_list (); register int i; if (the_list) for (i = 0; the_list[i]; i++) fprintf (stdout, "%d: %s\n", i + history_base, the_list[i]->line); } if (strncmp (line, "delete", strlen ("delete")) == 0) { int which; if ((sscanf (line + strlen ("delete"), "%d", &which)) == 1) { HIST_ENTRY *entry = remove_history (which); if (!entry) fprintf (stderr, "No such entry %d\n", which); else { free (entry->line); free (entry); } } else { fprintf (stderr, "non-numeric arg given to `delete'\n"); } } } } #endif /* TEST */ /* * Local variables: * compile-command: "gcc -g -DTEST -o history history.c" * end: */