xref: /linux/drivers/accessibility/speakup/keyhelp.c (revision c16ce856e422e73a54c41131e0332de1afe09b8b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /* speakup_keyhelp.c
3  * help module for speakup
4  *
5  *written by David Borowski.
6  *
7  *  Copyright (C) 2003  David Borowski.
8  */
9 
10 #include <linux/keyboard.h>
11 #include <linux/ctype.h>
12 #include "spk_priv.h"
13 #include "speakup.h"
14 
15 #define MAXFUNCS 130
16 #define MAXKEYS 256
17 static const int num_key_names = MSG_KEYNAMES_END - MSG_KEYNAMES_START + 1;
18 static u16 key_offsets[MAXFUNCS], key_data[MAXKEYS];
19 static u16 masks[] = { 32, 16, 8, 4, 2, 1 };
20 
21 static short letter_offsets[26] = {
22 	-1, -1, -1, -1, -1, -1, -1, -1,
23 	-1, -1, -1, -1, -1, -1, -1, -1,
24 	-1, -1, -1, -1, -1, -1, -1, -1,
25 	-1, -1 };
26 
27 static u_char funcvals[] = {
28 	ATTRIB_BLEEP_DEC, ATTRIB_BLEEP_INC, BLEEPS_DEC, BLEEPS_INC,
29 	SAY_FIRST_CHAR, SAY_LAST_CHAR, SAY_CHAR, SAY_CHAR_NUM,
30 	SAY_NEXT_CHAR, SAY_PHONETIC_CHAR, SAY_PREV_CHAR, SPEAKUP_PARKED,
31 	SPEAKUP_CUT, EDIT_DELIM, EDIT_EXNUM, EDIT_MOST,
32 	EDIT_REPEAT, EDIT_SOME, SPEAKUP_GOTO, BOTTOM_EDGE,
33 	LEFT_EDGE, RIGHT_EDGE, TOP_EDGE, SPEAKUP_HELP,
34 	SAY_LINE, SAY_NEXT_LINE, SAY_PREV_LINE, SAY_LINE_INDENT,
35 	SPEAKUP_PASTE, PITCH_DEC, PITCH_INC, PUNCT_DEC,
36 	PUNCT_INC, PUNC_LEVEL_DEC, PUNC_LEVEL_INC, SPEAKUP_QUIET,
37 	RATE_DEC, RATE_INC, READING_PUNC_DEC, READING_PUNC_INC,
38 	SAY_ATTRIBUTES, SAY_FROM_LEFT, SAY_FROM_TOP, SAY_POSITION,
39 	SAY_SCREEN, SAY_TO_BOTTOM, SAY_TO_RIGHT, SPK_KEY,
40 	SPK_LOCK, SPEAKUP_OFF, SPEECH_KILL, SPELL_DELAY_DEC,
41 	SPELL_DELAY_INC, SPELL_WORD, SPELL_PHONETIC, TONE_DEC,
42 	TONE_INC, VOICE_DEC, VOICE_INC, VOL_DEC,
43 	VOL_INC, CLEAR_WIN, SAY_WIN, SET_WIN,
44 	ENABLE_WIN, SAY_WORD, SAY_NEXT_WORD, SAY_PREV_WORD, 0
45 };
46 
47 static u_char *state_tbl;
48 static int cur_item, nstates;
49 
50 static void build_key_data(void)
51 {
52 	u_char *kp, counters[MAXFUNCS], ch, ch1;
53 	u16 *p_key, key;
54 	int i, offset = 1;
55 
56 	nstates = (int)(state_tbl[-1]);
57 	memset(counters, 0, sizeof(counters));
58 	memset(key_offsets, 0, sizeof(key_offsets));
59 	kp = state_tbl + nstates + 1;
60 	while (*kp++) {
61 		/* count occurrences of each function */
62 		for (i = 0; i < nstates; i++, kp++) {
63 			if (!*kp)
64 				continue;
65 			if ((state_tbl[i] & 16) != 0 && *kp == SPK_KEY)
66 				continue;
67 			counters[*kp]++;
68 		}
69 	}
70 	for (i = 0; i < MAXFUNCS; i++) {
71 		if (counters[i] == 0)
72 			continue;
73 		key_offsets[i] = offset;
74 		offset += (counters[i] + 1);
75 		if (offset >= MAXKEYS)
76 			break;
77 	}
78 /* leave counters set so high keycodes come first.
79  * this is done so num pad and other extended keys maps are spoken before
80  * the alpha with speakup type mapping.
81  */
82 	kp = state_tbl + nstates + 1;
83 	while ((ch = *kp++)) {
84 		for (i = 0; i < nstates; i++) {
85 			ch1 = *kp++;
86 			if (!ch1)
87 				continue;
88 			if ((state_tbl[i] & 16) != 0 && ch1 == SPK_KEY)
89 				continue;
90 			key = (state_tbl[i] << 8) + ch;
91 			counters[ch1]--;
92 			offset = key_offsets[ch1];
93 			if (!offset)
94 				continue;
95 			p_key = key_data + offset + counters[ch1];
96 			*p_key = key;
97 		}
98 	}
99 }
100 
101 static void say_key(int key)
102 {
103 	int i, state = key >> 8;
104 
105 	key &= 0xff;
106 	for (i = 0; i < 6; i++) {
107 		if (state & masks[i])
108 			synth_printf(" %s", spk_msg_get(MSG_STATES_START + i));
109 	}
110 	if ((key > 0) && (key <= num_key_names))
111 		synth_printf(" %s\n",
112 			     spk_msg_get(MSG_KEYNAMES_START + (key - 1)));
113 }
114 
115 static void help_init(void)
116 {
117 	char start = SPACE;
118 	int i;
119 	int num_funcs = MSG_FUNCNAMES_END - MSG_FUNCNAMES_START + 1;
120 
121 	state_tbl = spk_our_keys[0] + SHIFT_TBL_SIZE + 2;
122 	for (i = 0; i < num_funcs; i++) {
123 		char *cur_funcname = spk_msg_get(MSG_FUNCNAMES_START + i);
124 		char first_letter;
125 
126 		first_letter = tolower(*cur_funcname);
127 
128 		/* Accept only 'a'..'z' to index letter_offsets[] safely */
129 		if (first_letter < 'a' || first_letter > 'z')
130 			continue;
131 
132 		if (start == first_letter)
133 			continue;
134 		start = first_letter;
135 		letter_offsets[(start & 31) - 1] = i;
136 	}
137 }
138 
139 int spk_handle_help(struct vc_data *vc, u_char type, u_char ch, u16 key)
140 {
141 	int i, n;
142 	char *name;
143 	u_char func, *kp;
144 	u16 *p_keys, val;
145 
146 	if (letter_offsets[0] == -1)
147 		help_init();
148 	if (type == KT_LATIN) {
149 		if (ch == SPACE) {
150 			spk_special_handler = NULL;
151 			synth_printf("%s\n", spk_msg_get(MSG_LEAVING_HELP));
152 			return 1;
153 		}
154 		ch = tolower(ch);
155 		if (ch < 'a' || ch > 'z')
156 			return -1;
157 		if (letter_offsets[ch - 'a'] == -1) {
158 			synth_printf(spk_msg_get(MSG_NO_COMMAND), ch);
159 			synth_printf("\n");
160 			return 1;
161 		}
162 		cur_item = letter_offsets[ch - 'a'];
163 	} else if (type == KT_CUR) {
164 		if (ch == 0 &&
165 		    (MSG_FUNCNAMES_START + cur_item + 1) <= MSG_FUNCNAMES_END)
166 			cur_item++;
167 		else if (ch == 3 && cur_item > 0)
168 			cur_item--;
169 		else
170 			return -1;
171 	} else if (type == KT_SPKUP && ch == SPEAKUP_HELP &&
172 		   !spk_special_handler) {
173 		spk_special_handler = spk_handle_help;
174 		synth_printf("%s\n", spk_msg_get(MSG_HELP_INFO));
175 		build_key_data(); /* rebuild each time in case new mapping */
176 		return 1;
177 	} else {
178 		name = NULL;
179 		if ((type != KT_SPKUP) && (key > 0) && (key <= num_key_names)) {
180 			synth_printf("%s\n",
181 				     spk_msg_get(MSG_KEYNAMES_START + key - 1));
182 			return 1;
183 		}
184 		for (i = 0; funcvals[i] != 0 && !name; i++) {
185 			if (ch == funcvals[i])
186 				name = spk_msg_get(MSG_FUNCNAMES_START + i);
187 		}
188 		if (!name)
189 			return -1;
190 		kp = spk_our_keys[key] + 1;
191 		for (i = 0; i < nstates; i++) {
192 			if (ch == kp[i])
193 				break;
194 		}
195 		key += (state_tbl[i] << 8);
196 		say_key(key);
197 		synth_printf(spk_msg_get(MSG_KEYDESC), name);
198 		synth_printf("\n");
199 		return 1;
200 	}
201 	name = spk_msg_get(MSG_FUNCNAMES_START + cur_item);
202 	func = funcvals[cur_item];
203 	synth_printf("%s", name);
204 	if (key_offsets[func] == 0) {
205 		synth_printf(" %s\n", spk_msg_get(MSG_IS_UNASSIGNED));
206 		return 1;
207 	}
208 	p_keys = key_data + key_offsets[func];
209 	for (n = 0; p_keys[n]; n++) {
210 		val = p_keys[n];
211 		if (n > 0)
212 			synth_printf("%s ", spk_msg_get(MSG_DISJUNCTION));
213 		say_key(val);
214 	}
215 	return 1;
216 }
217