0965bee0 |
1 | /* |
2 | * ldisc.c: PuTTY line discipline. Sits between the input coming |
3 | * from keypresses in the window, and the output channel leading to |
4 | * the back end. Implements echo and/or local line editing, |
5 | * depending on what's currently configured. |
6 | */ |
7 | |
5bc238bb |
8 | #include <stdio.h> |
1d470ad2 |
9 | #include <ctype.h> |
5bc238bb |
10 | |
11 | #include "putty.h" |
12 | |
0965bee0 |
13 | #define ECHOING (cfg.localecho == LD_YES || \ |
14 | (cfg.localecho == LD_BACKEND && \ |
15 | (back->ldisc(LD_ECHO) || term_ldisc(LD_ECHO)))) |
16 | #define EDITING (cfg.localedit == LD_YES || \ |
17 | (cfg.localedit == LD_BACKEND && \ |
18 | (back->ldisc(LD_EDIT) || term_ldisc(LD_EDIT)))) |
5bc238bb |
19 | |
32874aea |
20 | static void c_write(char *buf, int len) |
21 | { |
fe50e814 |
22 | from_backend(0, buf, len); |
23 | } |
24 | |
5bc238bb |
25 | static char *term_buf = NULL; |
26 | static int term_buflen = 0, term_bufsiz = 0, term_quotenext = 0; |
27 | |
32874aea |
28 | static int plen(unsigned char c) |
29 | { |
8f22582c |
30 | if ((c >= 32 && c <= 126) || (c >= 160 && !in_utf)) |
32874aea |
31 | return 1; |
5bc238bb |
32 | else if (c < 128) |
32874aea |
33 | return 2; /* ^x for some x */ |
5bc238bb |
34 | else |
32874aea |
35 | return 4; /* <XY> for hex XY */ |
5bc238bb |
36 | } |
37 | |
32874aea |
38 | static void pwrite(unsigned char c) |
39 | { |
8f22582c |
40 | if ((c >= 32 && c <= 126) || (c >= 160 && !in_utf)) { |
32874aea |
41 | c_write(&c, 1); |
5bc238bb |
42 | } else if (c < 128) { |
32874aea |
43 | char cc[2]; |
44 | cc[1] = (c == 127 ? '?' : c + 0x40); |
45 | cc[0] = '^'; |
46 | c_write(cc, 2); |
5bc238bb |
47 | } else { |
32874aea |
48 | char cc[5]; |
49 | sprintf(cc, "<%02X>", c); |
50 | c_write(cc, 4); |
5bc238bb |
51 | } |
52 | } |
53 | |
32874aea |
54 | static void bsb(int n) |
55 | { |
5bc238bb |
56 | while (n--) |
57 | c_write("\010 \010", 3); |
58 | } |
59 | |
5d1d4279 |
60 | #define CTRL(x) (x^'@') |
a5f3e637 |
61 | #define KCTRL(x) ((x^'@') | 0x100) |
5d1d4279 |
62 | |
760e88b2 |
63 | void ldisc_send(char *buf, int len, int interactive) |
32874aea |
64 | { |
a5f3e637 |
65 | int keyflag = 0; |
0965bee0 |
66 | /* |
67 | * Called with len=0 when the options change. We must inform |
68 | * the front end in case it needs to know. |
69 | */ |
70 | if (len == 0) { |
32874aea |
71 | void ldisc_update(int echo, int edit); |
72 | ldisc_update(ECHOING, EDITING); |
5bc238bb |
73 | } |
0965bee0 |
74 | /* |
a5f3e637 |
75 | * Less than zero means null terminated special string. |
76 | */ |
77 | if (len < 0) { |
78 | len = strlen(buf); |
79 | keyflag = KCTRL('@'); |
80 | } |
81 | /* |
0965bee0 |
82 | * Either perform local editing, or just send characters. |
83 | */ |
84 | if (EDITING) { |
32874aea |
85 | while (len--) { |
a5f3e637 |
86 | int c; |
87 | c = *buf++ + keyflag; |
760e88b2 |
88 | if (!interactive && c == '\r') |
89 | c += KCTRL('@'); |
32874aea |
90 | switch (term_quotenext ? ' ' : c) { |
91 | /* |
92 | * ^h/^?: delete one char and output one BSB |
93 | * ^w: delete, and output BSBs, to return to last |
94 | * space/nonspace boundary |
95 | * ^u: delete, and output BSBs, to return to BOL |
96 | * ^c: Do a ^u then send a telnet IP |
97 | * ^z: Do a ^u then send a telnet SUSP |
98 | * ^\: Do a ^u then send a telnet ABORT |
99 | * ^r: echo "^R\n" and redraw line |
100 | * ^v: quote next char |
101 | * ^d: if at BOL, end of file and close connection, |
102 | * else send line and reset to BOL |
103 | * ^m: send line-plus-\r\n and reset to BOL |
104 | */ |
a5f3e637 |
105 | case KCTRL('H'): |
106 | case KCTRL('?'): /* backspace/delete */ |
32874aea |
107 | if (term_buflen > 0) { |
108 | if (ECHOING) |
109 | bsb(plen(term_buf[term_buflen - 1])); |
110 | term_buflen--; |
111 | } |
112 | break; |
113 | case CTRL('W'): /* delete word */ |
114 | while (term_buflen > 0) { |
115 | if (ECHOING) |
116 | bsb(plen(term_buf[term_buflen - 1])); |
117 | term_buflen--; |
118 | if (term_buflen > 0 && |
119 | isspace(term_buf[term_buflen - 1]) && |
120 | !isspace(term_buf[term_buflen])) |
121 | break; |
122 | } |
123 | break; |
124 | case CTRL('U'): /* delete line */ |
125 | case CTRL('C'): /* Send IP */ |
126 | case CTRL('\\'): /* Quit */ |
127 | case CTRL('Z'): /* Suspend */ |
128 | while (term_buflen > 0) { |
129 | if (ECHOING) |
130 | bsb(plen(term_buf[term_buflen - 1])); |
131 | term_buflen--; |
132 | } |
133 | back->special(TS_EL); |
2a8a449c |
134 | /* |
135 | * We don't send IP, SUSP or ABORT if the user has |
136 | * configured telnet specials off! This breaks |
137 | * talkers otherwise. |
138 | */ |
139 | if (!cfg.telnet_keyboard) |
140 | goto default_case; |
32874aea |
141 | if (c == CTRL('C')) |
142 | back->special(TS_IP); |
143 | if (c == CTRL('Z')) |
144 | back->special(TS_SUSP); |
145 | if (c == CTRL('\\')) |
146 | back->special(TS_ABORT); |
147 | break; |
148 | case CTRL('R'): /* redraw line */ |
149 | if (ECHOING) { |
150 | int i; |
151 | c_write("^R\r\n", 4); |
152 | for (i = 0; i < term_buflen; i++) |
153 | pwrite(term_buf[i]); |
154 | } |
155 | break; |
156 | case CTRL('V'): /* quote next char */ |
157 | term_quotenext = TRUE; |
158 | break; |
159 | case CTRL('D'): /* logout or send */ |
160 | if (term_buflen == 0) { |
161 | back->special(TS_EOF); |
162 | } else { |
163 | back->send(term_buf, term_buflen); |
164 | term_buflen = 0; |
165 | } |
166 | break; |
a5f3e637 |
167 | /* |
168 | * This particularly hideous bit of code from RDB |
169 | * allows ordinary ^M^J to do the same thing as |
170 | * magic-^M when in Raw protocol. The line `case |
171 | * KCTRL('M'):' is _inside_ the if block. Thus: |
172 | * |
173 | * - receiving regular ^M goes straight to the |
174 | * default clause and inserts as a literal ^M. |
175 | * - receiving regular ^J _not_ directly after a |
176 | * literal ^M (or not in Raw protocol) fails the |
177 | * if condition, leaps to the bottom of the if, |
178 | * and falls through into the default clause |
179 | * again. |
180 | * - receiving regular ^J just after a literal ^M |
181 | * in Raw protocol passes the if condition, |
182 | * deletes the literal ^M, and falls through |
183 | * into the magic-^M code |
184 | * - receiving a magic-^M empties the line buffer, |
185 | * signals end-of-line in one of the various |
186 | * entertaining ways, and _doesn't_ fall out of |
187 | * the bottom of the if and through to the |
188 | * default clause because of the break. |
189 | */ |
190 | case CTRL('J'): |
191 | if (cfg.protocol == PROT_RAW && |
192 | term_buflen > 0 && term_buf[term_buflen - 1] == '\r') { |
193 | if (ECHOING) |
194 | bsb(plen(term_buf[term_buflen - 1])); |
195 | term_buflen--; |
196 | /* FALLTHROUGH */ |
197 | case KCTRL('M'): /* send with newline */ |
198 | if (term_buflen > 0) |
199 | back->send(term_buf, term_buflen); |
200 | if (cfg.protocol == PROT_RAW) |
201 | back->send("\r\n", 2); |
eee63b77 |
202 | else if (cfg.protocol == PROT_TELNET && cfg.telnet_newline) |
a5f3e637 |
203 | back->special(TS_EOL); |
204 | else |
205 | back->send("\r", 1); |
206 | if (ECHOING) |
207 | c_write("\r\n", 2); |
208 | term_buflen = 0; |
209 | break; |
210 | } |
211 | /* FALLTHROUGH */ |
32874aea |
212 | default: /* get to this label from ^V handler */ |
2a8a449c |
213 | default_case: |
32874aea |
214 | if (term_buflen >= term_bufsiz) { |
215 | term_bufsiz = term_buflen + 256; |
216 | term_buf = saferealloc(term_buf, term_bufsiz); |
217 | } |
218 | term_buf[term_buflen++] = c; |
219 | if (ECHOING) |
a5f3e637 |
220 | pwrite((unsigned char) c); |
32874aea |
221 | term_quotenext = FALSE; |
222 | break; |
223 | } |
224 | } |
0965bee0 |
225 | } else { |
32874aea |
226 | if (term_buflen != 0) { |
227 | back->send(term_buf, term_buflen); |
228 | while (term_buflen > 0) { |
229 | bsb(plen(term_buf[term_buflen - 1])); |
230 | term_buflen--; |
231 | } |
232 | } |
233 | if (len > 0) { |
234 | if (ECHOING) |
235 | c_write(buf, len); |
a5f3e637 |
236 | if (keyflag && cfg.protocol == PROT_TELNET && len == 1) { |
237 | switch (buf[0]) { |
238 | case CTRL('M'): |
eee63b77 |
239 | if (cfg.protocol == PROT_TELNET && cfg.telnet_newline) |
240 | back->special(TS_EOL); |
241 | else |
242 | back->send("\r", 1); |
a5f3e637 |
243 | break; |
244 | case CTRL('?'): |
245 | case CTRL('H'): |
246 | if (cfg.telnet_keyboard) { |
247 | back->special(TS_EC); |
248 | break; |
249 | } |
250 | case CTRL('C'): |
251 | if (cfg.telnet_keyboard) { |
252 | back->special(TS_IP); |
253 | break; |
254 | } |
255 | case CTRL('Z'): |
256 | if (cfg.telnet_keyboard) { |
257 | back->special(TS_SUSP); |
258 | break; |
259 | } |
260 | |
261 | default: |
262 | back->send(buf, len); |
263 | break; |
264 | } |
265 | } else |
266 | back->send(buf, len); |
32874aea |
267 | } |
5d1d4279 |
268 | } |
5bc238bb |
269 | } |