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-rw-r--r--apps/plugins/frotz/text.c1109
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diff --git a/apps/plugins/frotz/text.c b/apps/plugins/frotz/text.c
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--- /dev/null
+++ b/apps/plugins/frotz/text.c
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+/* text.c - Text manipulation functions
+ * Copyright (c) 1995-1997 Stefan Jokisch
+ *
+ * This file is part of Frotz.
+ *
+ * Frotz 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Frotz 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include "frotz.h"
+
+enum string_type {
+ LOW_STRING, ABBREVIATION, HIGH_STRING, EMBEDDED_STRING, VOCABULARY
+};
+
+extern zword object_name (zword);
+
+static zchar decoded[10];
+static zword encoded[3];
+
+/*
+ * According to Matteo De Luigi <matteo.de.luigi@libero.it>,
+ * 0xab and 0xbb were in each other's proper positions.
+ * Sat Apr 21, 2001
+ */
+static zchar zscii_to_latin1[] = {
+ 0xe4, 0xf6, 0xfc, 0xc4, 0xd6, 0xdc, 0xdf, 0xbb,
+ 0xab, 0xeb, 0xef, 0xff, 0xcb, 0xcf, 0xe1, 0xe9,
+ 0xed, 0xf3, 0xfa, 0xfd, 0xc1, 0xc9, 0xcd, 0xd3,
+ 0xda, 0xdd, 0xe0, 0xe8, 0xec, 0xf2, 0xf9, 0xc0,
+ 0xc8, 0xcc, 0xd2, 0xd9, 0xe2, 0xea, 0xee, 0xf4,
+ 0xfb, 0xc2, 0xca, 0xce, 0xd4, 0xdb, 0xe5, 0xc5,
+ 0xf8, 0xd8, 0xe3, 0xf1, 0xf5, 0xc3, 0xd1, 0xd5,
+ 0xe6, 0xc6, 0xe7, 0xc7, 0xfe, 0xf0, 0xde, 0xd0,
+ 0xa3, 0x00, 0x00, 0xa1, 0xbf
+};
+
+/*
+ * translate_from_zscii
+ *
+ * Map a ZSCII character onto the ISO Latin-1 alphabet.
+ *
+ */
+
+zchar translate_from_zscii (zbyte c)
+{
+
+ if (c == 0xfc)
+ return ZC_MENU_CLICK;
+ if (c == 0xfd)
+ return ZC_DOUBLE_CLICK;
+ if (c == 0xfe)
+ return ZC_SINGLE_CLICK;
+
+ if (c >= 0x9b && story_id != BEYOND_ZORK) {
+
+ if (hx_unicode_table != 0) { /* game has its own Unicode table */
+
+ zbyte N;
+
+ LOW_BYTE (hx_unicode_table, N)
+
+ if (c - 0x9b < N) {
+
+ zword addr = hx_unicode_table + 1 + 2 * (c - 0x9b);
+ zword unicode;
+
+ LOW_WORD (addr, unicode)
+
+ return (unicode < 0x100) ? (zchar) unicode : '?';
+
+ } else return '?';
+
+ } else /* game uses standard set */
+
+ if (c <= 0xdf) {
+
+ if (c == 0xdc || c == 0xdd) /* Oe and oe ligatures */
+ return '?'; /* are not ISO-Latin 1 */
+
+ return zscii_to_latin1[c - 0x9b];
+
+ } else return '?';
+ }
+
+ return c;
+
+}/* translate_from_zscii */
+
+/*
+ * translate_to_zscii
+ *
+ * Map an ISO Latin-1 character onto the ZSCII alphabet.
+ *
+ */
+
+zbyte translate_to_zscii (zchar c)
+{
+ int i;
+
+ if (c == ZC_SINGLE_CLICK)
+ return 0xfe;
+ if (c == ZC_DOUBLE_CLICK)
+ return 0xfd;
+ if (c == ZC_MENU_CLICK)
+ return 0xfc;
+
+ if (c >= ZC_LATIN1_MIN) {
+
+ if (hx_unicode_table != 0) { /* game has its own Unicode table */
+
+ zbyte N;
+ int i;
+
+ LOW_BYTE (hx_unicode_table, N)
+
+ for (i = 0x9b; i < 0x9b + N; i++) {
+
+ zword addr = hx_unicode_table + 1 + 2 * (i - 0x9b);
+ zword unicode;
+
+ LOW_WORD (addr, unicode)
+
+ if (c == unicode)
+ return (zbyte) i;
+
+ }
+
+ return '?';
+
+ } else { /* game uses standard set */
+
+ for (i = 0x9b; i <= 0xdf; i++)
+ if (c == zscii_to_latin1[i - 0x9b])
+ return (zbyte) i;
+
+ return '?';
+
+ }
+ }
+
+ if (c == 0) /* Safety thing from David Kinder */
+ c = '?'; /* regarding his Unicode patches */
+ /* Sept 15, 2002 */
+
+ return c;
+
+}/* translate_to_zscii */
+
+/*
+ * alphabet
+ *
+ * Return a character from one of the three character sets.
+ *
+ */
+
+static zchar alphabet (int set, int index)
+{
+
+ if (h_alphabet != 0) { /* game uses its own alphabet */
+
+ zbyte c;
+
+ zword addr = h_alphabet + 26 * set + index;
+ LOW_BYTE (addr, c)
+
+ return translate_from_zscii (c);
+
+ } else /* game uses default alphabet */
+
+ if (set == 0)
+ return 'a' + index;
+ else if (set == 1)
+ return 'A' + index;
+ else if (h_version == V1)
+ return " 0123456789.,!?_#'\"/\\<-:()"[index];
+ else
+ return " ^0123456789.,!?_#'\"/\\-:()"[index];
+
+}/* alphabet */
+
+/*
+ * load_string
+ *
+ * Copy a ZSCII string from the memory to the global "decoded" string.
+ *
+ */
+
+static void load_string (zword addr, zword length)
+{
+ int resolution = (h_version <= V3) ? 2 : 3;
+ int i = 0;
+
+ while (i < 3 * resolution)
+
+ if (i < length) {
+
+ zbyte c;
+
+ LOW_BYTE (addr, c)
+ addr++;
+
+ decoded[i++] = translate_from_zscii (c);
+
+ } else decoded[i++] = 0;
+
+}/* load_string */
+
+/*
+ * encode_text
+ *
+ * Encode the Unicode text in the global "decoded" string then write
+ * the result to the global "encoded" array. (This is used to look up
+ * words in the dictionary.) Up to V3 the vocabulary resolution is
+ * two, since V4 it is three words. Because each word contains three
+ * Z-characters, that makes six or nine Z-characters respectively.
+ * Longer words are chopped to the proper size, shorter words are are
+ * padded out with 5's. For word completion we pad with 0s and 31s,
+ * the minimum and maximum Z-characters.
+ *
+ */
+
+static void encode_text (int padding)
+{
+ static zchar again[] = { 'a', 'g', 'a', 'i', 'n', 0 };
+ static zchar examine[] = { 'e', 'x', 'a', 'm', 'i', 'n', 'e', 0 };
+ static zchar wait[] = { 'w', 'a', 'i', 't', 0 };
+
+ zbyte zchars[12];
+ const zchar *ptr = decoded;
+ zchar c;
+ int resolution = (h_version <= V3) ? 2 : 3;
+ int i = 0;
+
+ /* Expand abbreviations that some old Infocom games lack */
+
+ if (f_setup.expand_abbreviations)
+
+ if (padding == 0x05 && decoded[1] == 0)
+
+ switch (decoded[0]) {
+ case 'g': ptr = again; break;
+ case 'x': ptr = examine; break;
+ case 'z': ptr = wait; break;
+ }
+
+ /* Translate string to a sequence of Z-characters */
+
+ while (i < 3 * resolution)
+
+ if ((c = *ptr++) != 0) {
+
+ int index, set;
+ zbyte c2;
+
+ /* Search character in the alphabet */
+
+ for (set = 0; set < 3; set++)
+ for (index = 0; index < 26; index++)
+ if (c == alphabet (set, index))
+ goto letter_found;
+
+ /* Character not found, store its ZSCII value */
+
+ c2 = translate_to_zscii (c);
+
+ zchars[i++] = 5;
+ zchars[i++] = 6;
+ zchars[i++] = c2 >> 5;
+ zchars[i++] = c2 & 0x1f;
+
+ continue;
+
+ letter_found:
+
+ /* Character found, store its index */
+
+ if (set != 0)
+ zchars[i++] = ((h_version <= V2) ? 1 : 3) + set;
+
+ zchars[i++] = index + 6;
+
+ } else zchars[i++] = padding;
+
+ /* Three Z-characters make a 16bit word */
+
+ for (i = 0; i < resolution; i++)
+
+ encoded[i] =
+ (zchars[3 * i + 0] << 10) |
+ (zchars[3 * i + 1] << 5) |
+ (zchars[3 * i + 2]);
+
+ encoded[resolution - 1] |= 0x8000;
+
+}/* encode_text */
+
+/*
+ * z_check_unicode, test if a unicode character can be read and printed.
+ *
+ * zargs[0] = Unicode
+ *
+ */
+
+void z_check_unicode (void)
+{
+ zword c = zargs[0];
+
+ if (c >= 0x20 && c <= 0x7e)
+ store (3);
+ else if (c == 0xa0)
+ store (1);
+ else if (c >= 0xa1 && c <= 0xff)
+ store (3);
+ else
+ store (0);
+
+}/* z_check_unicode */
+
+/*
+ * z_encode_text, encode a ZSCII string for use in a dictionary.
+ *
+ * zargs[0] = address of text buffer
+ * zargs[1] = length of ASCII string
+ * zargs[2] = offset of ASCII string within the text buffer
+ * zargs[3] = address to store encoded text in
+ *
+ * This is a V5+ opcode and therefore the dictionary resolution must be
+ * three 16bit words.
+ *
+ */
+
+void z_encode_text (void)
+{
+ int i;
+
+ load_string ((zword) (zargs[0] + zargs[2]), zargs[1]);
+
+ encode_text (0x05);
+
+ for (i = 0; i < 3; i++)
+ storew ((zword) (zargs[3] + 2 * i), encoded[i]);
+
+}/* z_encode_text */
+
+/*
+ * decode_text
+ *
+ * Convert encoded text to Unicode. The encoded text consists of 16bit
+ * words. Every word holds 3 Z-characters (5 bits each) plus a spare
+ * bit to mark the last word. The Z-characters translate to ZSCII by
+ * looking at the current current character set. Some select another
+ * character set, others refer to abbreviations.
+ *
+ * There are several different string types:
+ *
+ * LOW_STRING - from the lower 64KB (byte address)
+ * ABBREVIATION - from the abbreviations table (word address)
+ * HIGH_STRING - from the end of the memory map (packed address)
+ * EMBEDDED_STRING - from the instruction stream (at PC)
+ * VOCABULARY - from the dictionary (byte address)
+ *
+ * The last type is only used for word completion.
+ *
+ */
+
+#define outchar(c) if (st==VOCABULARY) *ptr++=c; else print_char(c)
+
+static void decode_text (enum string_type st, zword addr)
+{
+ zchar *ptr;
+ long byte_addr;
+ zchar c2;
+ zword code;
+ zbyte c, prev_c = 0;
+ int shift_state = 0;
+ int shift_lock = 0;
+ int status = 0;
+
+ ptr = NULL; /* makes compilers shut up */
+ byte_addr = 0;
+
+ /* Calculate the byte address if necessary */
+
+ if (st == ABBREVIATION)
+
+ byte_addr = (long) addr << 1;
+
+ else if (st == HIGH_STRING) {
+
+ if (h_version <= V3)
+ byte_addr = (long) addr << 1;
+ else if (h_version <= V5)
+ byte_addr = (long) addr << 2;
+ else if (h_version <= V7)
+ byte_addr = ((long) addr << 2) + ((long) h_strings_offset << 3);
+ else /* h_version == V8 */
+ byte_addr = (long) addr << 3;
+
+ if (byte_addr >= story_size)
+ runtime_error (ERR_ILL_PRINT_ADDR);
+
+ }
+
+ /* Loop until a 16bit word has the highest bit set */
+
+ if (st == VOCABULARY)
+ ptr = decoded;
+
+ do {
+
+ int i;
+
+ /* Fetch the next 16bit word */
+
+ if (st == LOW_STRING || st == VOCABULARY) {
+ LOW_WORD (addr, code)
+ addr += 2;
+ } else if (st == HIGH_STRING || st == ABBREVIATION) {
+ HIGH_WORD (byte_addr, code)
+ byte_addr += 2;
+ } else
+ CODE_WORD (code)
+
+ /* Read its three Z-characters */
+
+ for (i = 10; i >= 0; i -= 5) {
+
+ zword abbr_addr;
+ zword ptr_addr;
+
+ c = (code >> i) & 0x1f;
+
+ switch (status) {
+
+ case 0: /* normal operation */
+
+ if (shift_state == 2 && c == 6)
+ status = 2;
+
+ else if (h_version == V1 && c == 1)
+ new_line ();
+
+ else if (h_version >= V2 && shift_state == 2 && c == 7)
+ new_line ();
+
+ else if (c >= 6)
+ outchar (alphabet (shift_state, c - 6));
+
+ else if (c == 0)
+ outchar (' ');
+
+ else if (h_version >= V2 && c == 1)
+ status = 1;
+
+ else if (h_version >= V3 && c <= 3)
+ status = 1;
+
+ else {
+
+ shift_state = (shift_lock + (c & 1) + 1) % 3;
+
+ if (h_version <= V2 && c >= 4)
+ shift_lock = shift_state;
+
+ break;
+
+ }
+
+ shift_state = shift_lock;
+
+ break;
+
+ case 1: /* abbreviation */
+
+ ptr_addr = h_abbreviations + 64 * (prev_c - 1) + 2 * c;
+
+ LOW_WORD (ptr_addr, abbr_addr)
+ decode_text (ABBREVIATION, abbr_addr);
+
+ status = 0;
+ break;
+
+ case 2: /* ZSCII character - first part */
+
+ status = 3;
+ break;
+
+ case 3: /* ZSCII character - second part */
+
+ c2 = translate_from_zscii ((prev_c << 5) | c);
+ outchar (c2);
+
+ status = 0;
+ break;
+
+ }
+
+ prev_c = c;
+
+ }
+
+ } while (!(code & 0x8000));
+
+ if (st == VOCABULARY)
+ *ptr = 0;
+
+}/* decode_text */
+
+#undef outchar
+
+/*
+ * z_new_line, print a new line.
+ *
+ * no zargs used
+ *
+ */
+
+void z_new_line (void)
+{
+
+ new_line ();
+
+}/* z_new_line */
+
+/*
+ * z_print, print a string embedded in the instruction stream.
+ *
+ * no zargs used
+ *
+ */
+
+void z_print (void)
+{
+
+ decode_text (EMBEDDED_STRING, 0);
+
+}/* z_print */
+
+/*
+ * z_print_addr, print a string from the lower 64KB.
+ *
+ * zargs[0] = address of string to print
+ *
+ */
+
+void z_print_addr (void)
+{
+
+ decode_text (LOW_STRING, zargs[0]);
+
+}/* z_print_addr */
+
+/*
+ * z_print_char print a single ZSCII character.
+ *
+ * zargs[0] = ZSCII character to be printed
+ *
+ */
+
+void z_print_char (void)
+{
+
+ print_char (translate_from_zscii (zargs[0]));
+
+}/* z_print_char */
+
+/*
+ * z_print_form, print a formatted table.
+ *
+ * zargs[0] = address of formatted table to be printed
+ *
+ */
+
+void z_print_form (void)
+{
+ zword count;
+ zword addr = zargs[0];
+
+ bool first = TRUE;
+
+ for (;;) {
+
+ LOW_WORD (addr, count)
+ addr += 2;
+
+ if (count == 0)
+ break;
+
+ if (!first)
+ new_line ();
+
+ while (count--) {
+
+ zbyte c;
+
+ LOW_BYTE (addr, c)
+ addr++;
+
+ print_char (translate_from_zscii (c));
+
+ }
+
+ first = FALSE;
+
+ }
+
+}/* z_print_form */
+
+/*
+ * print_num
+ *
+ * Print a signed 16bit number.
+ *
+ */
+
+void print_num (zword value)
+{
+ int i;
+
+ /* Print sign */
+
+ if ((short) value < 0) {
+ print_char ('-');
+ value = - (short) value;
+ }
+
+ /* Print absolute value */
+
+ for (i = 10000; i != 0; i /= 10)
+ if (value >= i || i == 1)
+ print_char ('0' + (value / i) % 10);
+
+}/* print_num */
+
+/*
+ * z_print_num, print a signed number.
+ *
+ * zargs[0] = number to print
+ *
+ */
+
+void z_print_num (void)
+{
+
+ print_num (zargs[0]);
+
+}/* z_print_num */
+
+/*
+ * print_object
+ *
+ * Print an object description.
+ *
+ */
+
+void print_object (zword object)
+{
+ zword addr = object_name (object);
+ zword code = 0x94a5;
+ zbyte length;
+
+ LOW_BYTE (addr, length)
+ addr++;
+
+ if (length != 0)
+ LOW_WORD (addr, code)
+
+ if (code == 0x94a5) { /* encoded text 0x94a5 == empty string */
+
+ print_string ("object#"); /* supply a generic name */
+ print_num (object); /* for anonymous objects */
+
+ } else decode_text (LOW_STRING, addr);
+
+}/* print_object */
+
+/*
+ * z_print_obj, print an object description.
+ *
+ * zargs[0] = number of object to be printed
+ *
+ */
+
+void z_print_obj (void)
+{
+
+ print_object (zargs[0]);
+
+}/* z_print_obj */
+
+/*
+ * z_print_paddr, print the string at the given packed address.
+ *
+ * zargs[0] = packed address of string to be printed
+ *
+ */
+
+void z_print_paddr (void)
+{
+
+ decode_text (HIGH_STRING, zargs[0]);
+
+}/* z_print_paddr */
+
+/*
+ * z_print_ret, print the string at PC, print newline then return true.
+ *
+ * no zargs used
+ *
+ */
+
+void z_print_ret (void)
+{
+
+ decode_text (EMBEDDED_STRING, 0);
+ new_line ();
+ ret (1);
+
+}/* z_print_ret */
+
+/*
+ * print_string
+ *
+ * Print a string of ASCII characters.
+ *
+ */
+
+void print_string (const char *s)
+{
+ char c;
+
+ while ((c = *s++) != 0)
+
+ if (c == '\n')
+ new_line ();
+ else
+ print_char (c);
+
+}/* print_string */
+
+/*
+ * z_print_unicode
+ *
+ * zargs[0] = Unicode
+ *
+ */
+
+void z_print_unicode (void)
+{
+
+ print_char ((zargs[0] <= 0xff) ? zargs[0] : '?');
+
+}/* z_print_unicode */
+
+/*
+ * lookup_text
+ *
+ * Scan a dictionary searching for the given word. The first argument
+ * can be
+ *
+ * 0x00 - find the first word which is >= the given one
+ * 0x05 - find the word which exactly matches the given one
+ * 0x1f - find the last word which is <= the given one
+ *
+ * The return value is 0 if the search fails.
+ *
+ */
+
+static zword lookup_text (int padding, zword dct)
+{
+ zword entry_addr;
+ zword entry_count;
+ zword entry;
+ zword addr;
+ zbyte entry_len;
+ zbyte sep_count;
+ int resolution = (h_version <= V3) ? 2 : 3;
+ int entry_number;
+ int lower, upper;
+ int i;
+ bool sorted;
+
+ encode_text (padding);
+
+ LOW_BYTE (dct, sep_count) /* skip word separators */
+ dct += 1 + sep_count;
+ LOW_BYTE (dct, entry_len) /* get length of entries */
+ dct += 1;
+ LOW_WORD (dct, entry_count) /* get number of entries */
+ dct += 2;
+
+ if ((short) entry_count < 0) { /* bad luck, entries aren't sorted */
+
+ entry_count = - (short) entry_count;
+ sorted = FALSE;
+
+ } else sorted = TRUE; /* entries are sorted */
+
+ lower = 0;
+ upper = entry_count - 1;
+
+ while (lower <= upper) {
+
+ if (sorted) /* binary search */
+ entry_number = (lower + upper) / 2;
+ else /* linear search */
+ entry_number = lower;
+
+ entry_addr = dct + entry_number * entry_len;
+
+ /* Compare word to dictionary entry */
+
+ addr = entry_addr;
+
+ for (i = 0; i < resolution; i++) {
+ LOW_WORD (addr, entry)
+ if (encoded[i] != entry)
+ goto continuing;
+ addr += 2;
+ }
+
+ return entry_addr; /* exact match found, return now */
+
+ continuing:
+
+ if (sorted) /* binary search */
+
+ if (encoded[i] > entry)
+ lower = entry_number + 1;
+ else
+ upper = entry_number - 1;
+
+ else lower++; /* linear search */
+
+ }
+
+ /* No exact match has been found */
+
+ if (padding == 0x05)
+ return 0;
+
+ entry_number = (padding == 0x00) ? lower : upper;
+
+ if (entry_number == -1 || entry_number == entry_count)
+ return 0;
+
+ return dct + entry_number * entry_len;
+
+}/* lookup_text */
+
+/*
+ * tokenise_text
+ *
+ * Translate a single word to a token and append it to the token
+ * buffer. Every token consists of the address of the dictionary
+ * entry, the length of the word and the offset of the word from
+ * the start of the text buffer. Unknown words cause empty slots
+ * if the flag is set (such that the text can be scanned several
+ * times with different dictionaries); otherwise they are zero.
+ *
+ */
+
+static void tokenise_text (zword text, zword length, zword from, zword parse, zword dct, bool flag)
+{
+ zword addr;
+ zbyte token_max, token_count;
+
+ LOW_BYTE (parse, token_max)
+ parse++;
+ LOW_BYTE (parse, token_count)
+
+ if (token_count < token_max) { /* sufficient space left for token? */
+
+ storeb (parse++, token_count + 1);
+
+ load_string ((zword) (text + from), length);
+
+ addr = lookup_text (0x05, dct);
+
+ if (addr != 0 || !flag) {
+
+ parse += 4 * token_count;
+
+ storew ((zword) (parse + 0), addr);
+ storeb ((zword) (parse + 2), length);
+ storeb ((zword) (parse + 3), from);
+
+ }
+
+ }
+
+}/* tokenise_text */
+
+/*
+ * tokenise_line
+ *
+ * Split an input line into words and translate the words to tokens.
+ *
+ */
+
+void tokenise_line (zword text, zword token, zword dct, bool flag)
+{
+ zword addr1;
+ zword addr2;
+ zbyte length;
+ zbyte c;
+
+ length = 0; /* makes compilers shut up */
+
+ /* Use standard dictionary if the given dictionary is zero */
+
+ if (dct == 0)
+ dct = h_dictionary;
+
+ /* Remove all tokens before inserting new ones */
+
+ storeb ((zword) (token + 1), 0);
+
+ /* Move the first pointer across the text buffer searching for the
+ beginning of a word. If this succeeds, store the position in a
+ second pointer. Move the first pointer searching for the end of
+ the word. When it is found, "tokenise" the word. Continue until
+ the end of the buffer is reached. */
+
+ addr1 = text;
+ addr2 = 0;
+
+ if (h_version >= V5) {
+ addr1++;
+ LOW_BYTE (addr1, length)
+ }
+
+ do {
+
+ zword sep_addr;
+ zbyte sep_count;
+ zbyte separator;
+
+ /* Fetch next ZSCII character */
+
+ addr1++;
+
+ if (h_version >= V5 && addr1 == text + 2 + length)
+ c = 0;
+ else
+ LOW_BYTE (addr1, c)
+
+ /* Check for separator */
+
+ sep_addr = dct;
+
+ LOW_BYTE (sep_addr, sep_count)
+ sep_addr++;
+
+ do {
+
+ LOW_BYTE (sep_addr, separator)
+ sep_addr++;
+
+ } while (c != separator && --sep_count != 0);
+
+ /* This could be the start or the end of a word */
+
+ if (sep_count == 0 && c != ' ' && c != 0) {
+
+ if (addr2 == 0)
+ addr2 = addr1;
+
+ } else if (addr2 != 0) {
+
+ tokenise_text (
+ text,
+ (zword) (addr1 - addr2),
+ (zword) (addr2 - text),
+ token, dct, flag );
+
+ addr2 = 0;
+
+ }
+
+ /* Translate separator (which is a word in its own right) */
+
+ if (sep_count != 0)
+
+ tokenise_text (
+ text,
+ (zword) (1),
+ (zword) (addr1 - text),
+ token, dct, flag );
+
+ } while (c != 0);
+
+}/* tokenise_line */
+
+/*
+ * z_tokenise, make a lexical analysis of a ZSCII string.
+ *
+ * zargs[0] = address of string to analyze
+ * zargs[1] = address of token buffer
+ * zargs[2] = address of dictionary (optional)
+ * zargs[3] = set when unknown words cause empty slots (optional)
+ *
+ */
+
+void z_tokenise (void)
+{
+
+ /* Supply default arguments */
+
+ if (zargc < 3)
+ zargs[2] = 0;
+ if (zargc < 4)
+ zargs[3] = 0;
+
+ /* Call tokenise_line to do the real work */
+
+ tokenise_line (zargs[0], zargs[1], zargs[2], zargs[3] != 0);
+
+}/* z_tokenise */
+
+/*
+ * completion
+ *
+ * Scan the vocabulary to complete the last word on the input line
+ * (similar to "tcsh" under Unix). The return value is
+ *
+ * 2 ==> completion is impossible
+ * 1 ==> completion is ambiguous
+ * 0 ==> completion is successful
+ *
+ * The function also returns a string in its second argument. In case
+ * of 2, the string is empty; in case of 1, the string is the longest
+ * extension of the last word on the input line that is common to all
+ * possible completions (for instance, if the last word on the input
+ * is "fo" and its only possible completions are "follow" and "folly"
+ * then the string is "ll"); in case of 0, the string is an extension
+ * to the last word that results in the only possible completion.
+ *
+ */
+
+int completion (const zchar *buffer, zchar *result)
+{
+ zword minaddr;
+ zword maxaddr;
+ zchar *ptr;
+ zchar c;
+ int len;
+ int i;
+
+ *result = 0;
+
+ /* Copy last word to "decoded" string */
+
+ len = 0;
+
+ while ((c = *buffer++) != 0)
+
+ if (c != ' ') {
+
+ if (len < 9)
+ decoded[len++] = c;
+
+ } else len = 0;
+
+ decoded[len] = 0;
+
+ /* Search the dictionary for first and last possible extensions */
+
+ minaddr = lookup_text (0x00, h_dictionary);
+ maxaddr = lookup_text (0x1f, h_dictionary);
+
+ if (minaddr == 0 || maxaddr == 0 || minaddr > maxaddr)
+ return 2;
+
+ /* Copy first extension to "result" string */
+
+ decode_text (VOCABULARY, minaddr);
+
+ ptr = result;
+
+ for (i = len; (c = decoded[i]) != 0; i++)
+ *ptr++ = c;
+ *ptr = 0;
+
+ /* Merge second extension with "result" string */
+
+ decode_text (VOCABULARY, maxaddr);
+
+ for (i = len, ptr = result; (c = decoded[i]) != 0; i++, ptr++)
+ if (*ptr != c) break;
+ *ptr = 0;
+
+ /* Search was ambiguous or successful */
+
+ return (minaddr == maxaddr) ? 0 : 1;
+
+}/* completion */