1 /* stty.c - Get/set terminal configuration.
2  *
3  * Copyright 2017 The Android Open Source Project.
4  *
5  * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/stty.html
6 
7 USE_STTY(NEWTOY(stty, "?aF:g[!ag]", TOYFLAG_BIN))
8 
9 config STTY
10   bool "stty"
11   default n
12   help
13     usage: stty [-ag] [-F device] SETTING...
14 
15     Get/set terminal configuration.
16 
17     -F	Open device instead of stdin
18     -a	Show all current settings (default differences from "sane")
19     -g	Show all current settings usable as input to stty
20 
21     Special characters (syntax ^c or undef): intr quit erase kill eof eol eol2
22     swtch start stop susp rprnt werase lnext discard
23 
24     Control/input/output/local settings as shown by -a, '-' prefix to disable
25 
26     Combo settings: cooked/raw, evenp/oddp/parity, nl, ek, sane
27 
28     N	set input and output speed (ispeed N or ospeed N for just one)
29     cols N	set number of columns
30     rows N	set number of rows
31     line N	set line discipline
32     min N	set minimum chars per read
33     time N	set read timeout
34     speed	show speed only
35     size	show size only
36 */
37 
38 #define FOR_stty
39 #include "toys.h"
40 
41 #include <linux/tty.h>
42 
43 GLOBALS(
44   char *F;
45 
46   int fd, col;
47   unsigned output_cols;
48 )
49 
50 static const int bauds[] = {
51   0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600,
52   19200, 38400, 57600, 115200, 230400, 460800, 500000, 576000, 921600,
53   1000000, 1152000, 1500000, 2000000, 2500000, 3000000, 3500000, 4000000
54 };
55 
baud(speed_t speed)56 static int baud(speed_t speed)
57 {
58   if (speed&CBAUDEX) speed=(speed&~CBAUDEX)+15;
59   return bauds[speed];
60 }
61 
speed(int baud)62 static speed_t speed(int baud)
63 {
64   int i;
65 
66   for (i=0;i<ARRAY_LEN(bauds);i++) if (bauds[i] == baud) break;
67   if (i == ARRAY_LEN(bauds)) error_exit("unknown speed: %d", baud);
68   return i+4081*(i>16);
69 }
70 
71 struct flag {
72   char *name;
73   int value;
74   int mask;
75 };
76 
77 static const struct flag chars[] = {
78   { "intr", VINTR }, { "quit", VQUIT }, { "erase", VERASE }, { "kill", VKILL },
79   { "eof", VEOF }, { "eol", VEOL }, { "eol2", VEOL2 }, { "swtch", VSWTC },
80   { "start", VSTART }, { "stop", VSTOP }, { "susp", VSUSP },
81   { "rprnt", VREPRINT }, { "werase", VWERASE }, { "lnext", VLNEXT },
82   { "discard", VDISCARD }, { "min", VMIN }, { "time", VTIME },
83 };
84 
85 static const struct flag cflags[] = {
86   { "parenb", PARENB }, { "parodd", PARODD }, { "cmspar", CMSPAR },
87   { "cs5", CS5, CSIZE }, { "cs6", CS6, CSIZE }, { "cs7", CS7, CSIZE },
88   { "cs8", CS8, CSIZE }, { "hupcl", HUPCL }, { "cstopb", CSTOPB },
89   { "cread", CREAD }, { "clocal", CLOCAL }, { "crtscts", CRTSCTS },
90 };
91 
92 static const struct flag iflags[] = {
93   { "ignbrk", IGNBRK }, { "brkint", BRKINT }, { "ignpar", IGNPAR },
94   { "parmrk", PARMRK }, { "inpck", INPCK }, { "istrip", ISTRIP },
95   { "inlcr", INLCR }, { "igncr", IGNCR }, { "icrnl", ICRNL }, { "ixon", IXON },
96   { "ixoff", IXOFF }, { "iuclc", IUCLC }, { "ixany", IXANY },
97   { "imaxbel", IMAXBEL }, { "iutf8", IUTF8 },
98 };
99 
100 static const struct flag oflags[] = {
101   { "opost", OPOST }, { "olcuc", OLCUC }, { "ocrnl", OCRNL },
102   { "onlcr", ONLCR }, { "onocr", ONOCR }, { "onlret", ONLRET },
103   { "ofill", OFILL }, { "ofdel", OFDEL }, { "nl0", NL0, NLDLY },
104   { "nl1", NL1, NLDLY }, { "cr0", CR0, CRDLY }, { "cr1", CR1, CRDLY },
105   { "cr2", CR2, CRDLY }, { "cr3", CR3, CRDLY }, { "tab0", TAB0, TABDLY },
106   { "tab1", TAB1, TABDLY }, { "tab2", TAB2, TABDLY }, { "tab3", TAB3, TABDLY },
107   { "bs0", BS0, BSDLY }, { "bs1", BS1, BSDLY }, { "vt0", VT0, VTDLY },
108   { "vt1", VT1, VTDLY }, { "ff0", FF0, FFDLY }, { "ff1", FF1, FFDLY },
109 };
110 
111 static const struct flag lflags[] = {
112   { "isig", ISIG }, { "icanon", ICANON }, { "iexten", IEXTEN },
113   { "echo", ECHO }, { "echoe", ECHOE }, { "echok", ECHOK },
114   { "echonl", ECHONL }, { "noflsh", NOFLSH }, { "xcase", XCASE },
115   { "tostop", TOSTOP }, { "echoprt", ECHOPRT }, { "echoctl", ECHOCTL },
116   { "echoke", ECHOKE }, { "flusho", FLUSHO }, { "extproc", EXTPROC },
117 };
118 
119 static const struct synonym {
120   char *from;
121   char *to;
122 } synonyms[] = {
123   { "cbreak", "-icanon" }, { "-cbreak", "icanon" },
124   { "-cooked", "raw" }, { "-raw", "cooked" },
125   { "crterase", "echoe" }, { "-crterase", "-echoe" },
126   { "crtkill", "echoke" }, { "-crtkill", "-echoke" },
127   { "ctlecho", "echoctl" }, { "-ctlecho", "-echoctl" },
128   { "-tandem", "-ixoff" }, { "tandem", "ixoff" },
129   { "hup", "hupcl" }, { "-hup", "-hupcl" },
130   { "prterase", "echoprt" }, { "-prterase", "-echoprt" },
131   { "tabs", "tab0" }, { "-tabs", "tab3" },
132 };
133 
out(const char * fmt,...)134 static void out(const char *fmt, ...)
135 {
136   va_list va;
137   int len;
138   char *prefix = " ";
139 
140   va_start(va, fmt);
141   len = vsnprintf(toybuf, sizeof(toybuf), fmt, va);
142   va_end(va);
143 
144   if (TT.output_cols == 0) {
145     TT.output_cols = 80;
146     terminal_size(&TT.output_cols, NULL);
147   }
148 
149   if (TT.col == 0 || *fmt == '\n') prefix = "";
150   else if (TT.col + 1 + len >= TT.output_cols) {
151     prefix = "\n";
152     TT.col = 0;
153   }
154   xprintf("%s%s", prefix, toybuf);
155 
156   if (toybuf[len-1] == '\n') TT.col = 0;
157   else TT.col += strlen(prefix) + len;
158 }
159 
show_flags(tcflag_t actual,tcflag_t sane,const struct flag * flags,int len)160 static void show_flags(tcflag_t actual, tcflag_t sane,
161                        const struct flag *flags, int len)
162 {
163   int i, j, value, mask;
164 
165   // Implement -a by ensuring that sane != actual so we'll show everything.
166   if (FLAG(a)) sane = ~actual;
167 
168   for (i = j = 0; i<len; i++) {
169     value = flags[i].value;
170     if ((mask = flags[i].mask)) {
171       if ((actual&mask)==value && (sane&mask)!=value) {
172         out("%s", flags[i].name);
173         j++;
174       }
175     } else {
176       if ((actual&value) != (sane&value)) {
177         out("%s%s", actual&value?"":"-", flags[i].name);
178         j++;
179       }
180     }
181   }
182   if (j) out("\n");
183 }
184 
show_size(int verbose)185 static void show_size(int verbose)
186 {
187   struct winsize ws;
188 
189   if (ioctl(TT.fd, TIOCGWINSZ, &ws)) perror_exit("TIOCGWINSZ %s", TT.F);
190   out(verbose ? "rows %d; columns %d;" : "%d %d\n", ws.ws_row, ws.ws_col);
191 }
192 
show_speed(struct termios * t,int verbose)193 static void show_speed(struct termios *t, int verbose)
194 {
195   int ispeed = baud(cfgetispeed(t)), ospeed = baud(cfgetospeed(t));
196   char *fmt = verbose ? "ispeed %d baud; ospeed %d baud;" : "%d %d\n";
197 
198   if (ispeed == ospeed) fmt += (verbose ? 17 : 3);
199   out(fmt, ispeed, ospeed);
200 }
201 
get_arg(int * i,long long high)202 static int get_arg(int *i, long long high)
203 {
204   (*i)++;
205   if (!toys.optargs[*i]) error_exit("missing arg");
206   return atolx_range(toys.optargs[*i], 0, high);
207 }
208 
set_flag(tcflag_t * f,const struct flag * flags,int len,char * name,int on)209 static int set_flag(tcflag_t *f, const struct flag *flags, int len,
210                     char *name, int on)
211 {
212   int i;
213 
214   for (i=0;i<len;i++) {
215     if (!strcmp(flags[i].name, name)) {
216       if (on) {
217         *f &= ~flags[i].mask;
218         *f |= flags[i].value;
219       } else {
220         if (flags[i].mask) error_exit("%s isn't a boolean", name);
221         *f &= ~flags[i].value;
222       }
223       return 1;
224     }
225   }
226   return 0;
227 }
228 
set_option(struct termios * new,char * option)229 static void set_option(struct termios *new, char *option)
230 {
231   int on = (*option != '-');
232 
233   if (!on) option++;
234   if (!set_flag(&new->c_cflag, cflags, ARRAY_LEN(cflags), option, on) &&
235       !set_flag(&new->c_iflag, iflags, ARRAY_LEN(iflags), option, on) &&
236       !set_flag(&new->c_oflag, oflags, ARRAY_LEN(oflags), option, on) &&
237       !set_flag(&new->c_lflag, lflags, ARRAY_LEN(lflags), option, on))
238     error_exit("unknown option: %s", option);
239 }
240 
set_options(struct termios * new,...)241 static void set_options(struct termios* new, ...)
242 {
243   va_list va;
244   char *option;
245 
246   va_start(va, new);
247   while ((option = va_arg(va, char *))) set_option(new, option);
248   va_end(va);
249 }
250 
set_size(int is_rows,unsigned short value)251 static void set_size(int is_rows, unsigned short value)
252 {
253   struct winsize ws;
254 
255   if (ioctl(TT.fd, TIOCGWINSZ, &ws)) perror_exit("TIOCGWINSZ %s", TT.F);
256   if (is_rows) ws.ws_row = value;
257   else ws.ws_col = value;
258   if (ioctl(TT.fd, TIOCSWINSZ, &ws)) perror_exit("TIOCSWINSZ %s", TT.F);
259 }
260 
set_special_character(struct termios * new,int * i,char * char_name)261 static int set_special_character(struct termios *new, int *i, char *char_name)
262 {
263   int j;
264 
265   // The -2 is to ignore VMIN and VTIME, which are just unsigned integers.
266   for (j=0;j<ARRAY_LEN(chars)-2;j++) {
267     if (!strcmp(chars[j].name, char_name)) {
268       char *arg = toys.optargs[++(*i)];
269       cc_t ch;
270 
271       if (!arg) error_exit("missing arg");
272       if (!strcmp(arg, "^-") || !strcmp(arg, "undef")) ch = _POSIX_VDISABLE;
273       else if (!strcmp(arg, "^?")) ch = 0x7f;
274       else if (arg[0] == '^' && arg[2] == 0) ch = (toupper(arg[1])-'@');
275       else if (!arg[1]) ch = arg[0];
276       else error_exit("invalid arg: %s", arg);
277       new->c_cc[chars[j].value] = ch;
278       return 1;
279     }
280   }
281   return 0;
282 }
283 
make_sane(struct termios * t)284 static void make_sane(struct termios *t)
285 {
286   // POSIX has no opinion about what "sane" means. From "man stty".
287   // "cs8" is missing from the man page, but needed to get identical results.
288   set_options(t, "cread", "-ignbrk", "brkint", "-inlcr", "-igncr", "icrnl",
289     "icanon", "iexten", "echo", "echoe", "echok", "-echonl", "-noflsh",
290     "-ixoff", "-iutf8", "-iuclc", "-ixany", "imaxbel", "-xcase", "-olcuc",
291     "-ocrnl", "opost", "-ofill", "onlcr", "-onocr", "-onlret", "nl0", "cr0",
292     "tab0", "bs0", "vt0", "ff0", "isig", "-tostop", "-ofdel", "-echoprt",
293     "echoctl", "echoke", "-extproc", "-flusho", "cs8", NULL);
294   memset(t->c_cc, 0, NCCS);
295   t->c_cc[VINTR] = 0x3;
296   t->c_cc[VQUIT] = 0x1c;
297   t->c_cc[VERASE] = 0x7f;
298   t->c_cc[VKILL] = 0x15;
299   t->c_cc[VEOF] = 0x4;
300   t->c_cc[VTIME] = 0;
301   t->c_cc[VMIN] = 1;
302   t->c_cc[VSWTC] = 0;
303   t->c_cc[VSTART] = 0x11;
304   t->c_cc[VSTOP] = 0x13;
305   t->c_cc[VSUSP] = 0x1a;
306   t->c_cc[VEOL] = 0;
307   t->c_cc[VREPRINT] = 0x12;
308   t->c_cc[VDISCARD] = 0xf;
309   t->c_cc[VWERASE] = 0x17;
310   t->c_cc[VLNEXT] = 0x16;
311   t->c_cc[VEOL2] = 0;
312 }
313 
xtcgetattr(struct termios * t)314 static void xtcgetattr(struct termios *t)
315 {
316   if (tcgetattr(TT.fd, t)) perror_exit("tcgetattr %s", TT.F);
317 }
318 
stty_main(void)319 void stty_main(void)
320 {
321   struct termios old, sane;
322   int i, j, n;
323 
324   if (toys.optflags&(FLAG_a|FLAG_g) && *toys.optargs)
325     error_exit("no settings with -a/-g");
326 
327   if (!TT.F) TT.F = "standard input";
328   else TT.fd = xopen(TT.F, (O_RDWR*!!*toys.optargs)|O_NOCTTY|O_NONBLOCK);
329 
330   xtcgetattr(&old);
331 
332   if (*toys.optargs) {
333     struct termios new = old, tmp;
334 
335     for (i=0; toys.optargs[i]; i++) {
336       char *arg = toys.optargs[i];
337 
338       if (!strcmp(arg, "size")) show_size(0);
339       else if (!strcmp(arg, "speed")) show_speed(&old, 0);
340       else if (!strcmp(arg, "line")) new.c_line = get_arg(&i, NR_LDISCS);
341       else if (!strcmp(arg, "min")) new.c_cc[VMIN] = get_arg(&i, 255);
342       else if (!strcmp(arg, "time")) new.c_cc[VTIME] = get_arg(&i, 255);
343       else if (sscanf(arg, "%x:%x:%x:%x:%n", &tmp.c_iflag, &tmp.c_oflag,
344                         &tmp.c_cflag, &tmp.c_lflag, &n) == 4)
345       {
346         int value;
347 
348         new.c_iflag = tmp.c_iflag;
349         new.c_oflag = tmp.c_oflag;
350         new.c_cflag = tmp.c_cflag;
351         new.c_lflag = tmp.c_lflag;
352         arg += n;
353         for (j=0;j<NCCS;j++) {
354           if (sscanf(arg, "%x%n", &value, &n) != 1) error_exit("bad -g string");
355           new.c_cc[j] = value;
356           arg += n+1;
357         }
358       } else if (atoi(arg) > 0) {
359         int new_speed = speed(atolx_range(arg, 0, 4000000));
360 
361         cfsetispeed(&new, new_speed);
362         cfsetospeed(&new, new_speed);
363       } else if (!strcmp(arg, "ispeed"))
364         cfsetispeed(&new, speed(get_arg(&i, 4000000)));
365       else if (!strcmp(arg, "ospeed"))
366         cfsetospeed(&new, speed(get_arg(&i, 4000000)));
367       else if (!strcmp(arg, "rows")) set_size(1, get_arg(&i, USHRT_MAX));
368       else if (!strcmp(arg, "cols") || !strcmp(arg, "columns"))
369         set_size(0, get_arg(&i, USHRT_MAX));
370       else if (set_special_character(&new, &i, arg));
371         // Already done as a side effect.
372       else if (!strcmp(arg, "cooked"))
373         set_options(&new, "brkint", "ignpar", "istrip", "icrnl", "ixon",
374           "opost", "isig", "icanon", NULL);
375       else if (!strcmp(arg, "evenp") || !strcmp(arg, "parity"))
376         set_options(&new, "parenb", "cs7", "-parodd", NULL);
377       else if (!strcmp(arg, "oddp"))
378         set_options(&new, "parenb", "cs7", "parodd", NULL);
379       else if (!strcmp(arg, "-parity") || !strcmp(arg, "-evenp") ||
380                  !strcmp(arg, "-oddp")) {
381         set_options(&new, "-parenb", "cs8", NULL);
382       } else if (!strcmp(arg, "raw")) {
383         // POSIX and "man stty" differ wildly. This is "man stty".
384         set_options(&new, "-ignbrk", "-brkint", "-ignpar", "-parmrk", "-inpck",
385           "-istrip", "-inlcr", "-igncr", "-icrnl", "-ixon", "-ixoff", "-iuclc",
386           "-ixany", "-imaxbel", "-opost", "-isig", "-icanon", "-xcase", NULL);
387         new.c_cc[VMIN] = 1;
388         new.c_cc[VTIME] = 0;
389       } else if (!strcmp(arg, "nl"))
390         set_options(&new, "-icrnl", "-ocrnl", NULL);
391       else if (!strcmp(arg, "-nl"))
392         set_options(&new, "icrnl", "ocrnl", "-inlcr", "-igncr", NULL);
393       else if (!strcmp(arg, "ek")) {
394         new.c_cc[VERASE] = 0x7f;
395         new.c_cc[VKILL] = 0x15;
396       } else if (!strcmp(arg, "sane")) make_sane(&new);
397       else {
398         // Translate historical cruft into canonical forms.
399         for (j=0; j<ARRAY_LEN(synonyms); j++) {
400           if (!strcmp(synonyms[j].from, arg)) {
401             arg = synonyms[j].to;
402             break;
403           }
404         }
405         set_option(&new, arg);
406       }
407     }
408 
409     tcsetattr(TT.fd, TCSAFLUSH, &new);
410     xtcgetattr(&old);
411     if (memcmp(&old, &new, sizeof(old)))
412       error_exit("unable to perform all requested operations on %s", TT.F);
413 
414     return;
415   }
416 
417   if (FLAG(g)) {
418     xprintf("%x:%x:%x:%x:", old.c_iflag, old.c_oflag, old.c_cflag, old.c_lflag);
419     for (i=0;i<NCCS;i++) xprintf("%x%c", old.c_cc[i], i==NCCS-1?'\n':':');
420     return;
421   }
422 
423   // Without arguments, "stty" only shows the speed, the line discipline,
424   // special characters and any flags that differ from the "sane" settings.
425   make_sane(&sane);
426   show_speed(&old, 1);
427   if (FLAG(a)) show_size(1);
428   out("line = %d;\n", old.c_line);
429 
430   for (i=j=0; i<ARRAY_LEN(chars); i++) {
431     char vis[16] = {};
432     cc_t ch = old.c_cc[chars[i].value];
433 
434     if (ch == sane.c_cc[chars[i].value] && !FLAG(a))
435       continue;
436 
437     if (chars[i].value == VMIN || chars[i].value == VTIME)
438       snprintf(vis, sizeof(vis), "%u", ch);
439     else if (ch == _POSIX_VDISABLE) strcat(vis, "<undef>");
440     else {
441       if (ch > 0x7f) {
442         strcat(vis, "M-");
443         ch -= 128;
444       }
445       if (ch < ' ') sprintf(vis+strlen(vis), "^%c", (ch+'@'));
446       else if (ch == 0x7f) strcat(vis, "^?");
447       else sprintf(vis+strlen(vis), "%c", ch);
448     }
449     out("%s = %s;", chars[i].name, vis);
450     j++;
451   }
452   if (j) out("\n");
453 
454   show_flags(old.c_cflag, sane.c_cflag, cflags, ARRAY_LEN(cflags));
455   show_flags(old.c_iflag, sane.c_iflag, iflags, ARRAY_LEN(iflags));
456   show_flags(old.c_oflag, sane.c_oflag, oflags, ARRAY_LEN(oflags));
457   show_flags(old.c_lflag, sane.c_lflag, lflags, ARRAY_LEN(lflags));
458 
459   if (TT.fd) close(TT.fd);
460 }
461