diff options
Diffstat (limited to 'contrib/gperf/src/listnode.c')
| -rw-r--r-- | contrib/gperf/src/listnode.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/contrib/gperf/src/listnode.c b/contrib/gperf/src/listnode.c new file mode 100644 index 0000000..2eec1a6 --- /dev/null +++ b/contrib/gperf/src/listnode.c @@ -0,0 +1,111 @@ +/* Creates and initializes a new list node. + Copyright (C) 1989 Free Software Foundation, Inc. + written by Douglas C. Schmidt (schmidt@ics.uci.edu) + +This file is part of GNU GPERF. + +GNU GPERF 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. + +GNU GPERF 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. + +You should have received a copy of the GNU General Public License +along with GNU GPERF; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include <stdio.h> +#include "options.h" +#include "listnode.h" +#include "stderr.h" + +/* See comments in perfect.cc. */ +extern int occurrences[ALPHABET_SIZE]; + +/* Sorts the key set alphabetically to speed up subsequent operations. + Uses insertion sort since the set is probably quite small. */ + +static void +set_sort (base, len) + char *base; + int len; +{ + int i, j; + + for (i = 0, j = len - 1; i < j; i++) + { + char curr, tmp; + + for (curr = i + 1, tmp = base[curr]; curr > 0 && tmp < base[curr-1]; curr--) + base[curr] = base[curr - 1]; + + base[curr] = tmp; + + } +} + +/* Initializes a List_Node. This requires obtaining memory for the KEY_SET + initializing them using the information stored in the + KEY_POSITIONS array in Options, and checking for simple errors. + It's important to note that KEY and REST are both pointers to + the different offsets into the same block of dynamic memory pointed to + by parameter K. The data member REST is used to store any additional fields + of the input file (it is set to the "" string if Option[TYPE] is not enabled). + This is useful if the user wishes to incorporate a lookup structure, + rather than just an array of keys. */ + +LIST_NODE * +make_list_node (k, len) + char *k; + int len; +{ + LIST_NODE *buffered_malloc (); + int char_set_size = OPTION_ENABLED (option, ALLCHARS) ? len : GET_CHARSET_SIZE (option) + 1; + LIST_NODE *temp = buffered_malloc (sizeof (LIST_NODE) + char_set_size); + char *ptr = temp->char_set; + + k[len] = '\0'; /* Null terminate KEY to separate it from REST. */ + temp->key = k; + temp->next = 0; + temp->index = 0; + temp->length = len; + temp->link = 0; + temp->rest = OPTION_ENABLED (option, TYPE) ? k + len + 1 : ""; + + if (OPTION_ENABLED (option, ALLCHARS)) /* Use all the character position in the KEY. */ + + for (; *k; k++, ptr++) + ++occurrences[*ptr = *k]; + + else /* Only use those character positions specified by the user. */ + { + int i; + + /* Iterate thru the list of key_positions, initializing occurrences table + and temp->char_set (via char * pointer ptr). */ + + for(RESET (option); (i = GET (option)) != EOS; ) + { + if (i == WORD_END) /* Special notation for last KEY position, i.e. '$'. */ + *ptr = temp->key[len - 1]; + else if (i <= len) /* Within range of KEY length, so we'll keep it. */ + *ptr = temp->key[i - 1]; + else /* Out of range of KEY length, so we'll just skip it. */ + continue; + ++occurrences[*ptr++]; + } + + if (ptr == temp->char_set) /* Didn't get any hits, i.e., no usable positions. */ + report_error ("can't hash keyword %s with chosen key positions\n%a", temp->key); + } + + *ptr = '\0'; /* Terminate this bastard.... */ + /* Sort the KEY_SET items alphabetically. */ + set_sort (temp->char_set, ptr - temp->char_set); + + return temp; +} |
