1 /* linenoise.c -- guerrilla line editing library against the idea that a
2 * line editing lib needs to be 20,000 lines of C code.
4 * You can find the latest source code at:
6 * http://github.com/antirez/linenoise
8 * Does a number of crazy assumptions that happen to be true in 99.9999% of
9 * the 2010 UNIX computers around.
11 * Copyright (c) 2010, Salvatore Sanfilippo <antirez at gmail dot com>
12 * All rights reserved.
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are met:
17 * * Redistributions of source code must retain the above copyright notice,
18 * this list of conditions and the following disclaimer.
19 * * Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 * * Neither the name of Redis nor the names of its contributors may be used
23 * to endorse or promote products derived from this software without
24 * specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
39 * - http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
40 * - http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html
43 * - Switch to gets() if $TERM is something we can't support.
44 * - Filter bogus Ctrl+<char> combinations.
49 * - History search like Ctrl+r in readline?
51 * List of escape sequences used by this program, we do everything just
52 * with three sequences. In order to be so cheap we may have some
53 * flickering effect with some slow terminal, but the lesser sequences
54 * the more compatible.
56 * CHA (Cursor Horizontal Absolute)
58 * Effect: moves cursor to column n
62 * Effect: if n is 0 or missing, clear from cursor to end of line
63 * Effect: if n is 1, clear from beginning of line to cursor
64 * Effect: if n is 2, clear entire line
66 * CUF (CUrsor Forward)
68 * Effect: moves cursor forward of n chars
79 #include <sys/types.h>
80 #include <sys/ioctl.h>
82 #include "linenoise.h"
84 #define LINENOISE_DEFAULT_HISTORY_MAX_LEN 100
85 #define LINENOISE_MAX_LINE 4096
86 static char *unsupported_term[] = {"dumb","cons25",NULL};
87 static linenoiseCompletionCallback *completionCallback = NULL;
89 static struct termios orig_termios; /* in order to restore at exit */
90 static int rawmode = 0; /* for atexit() function to check if restore is needed*/
91 static int atexit_registered = 0; /* register atexit just 1 time */
92 static int history_max_len = LINENOISE_DEFAULT_HISTORY_MAX_LEN;
93 static int history_len = 0;
94 char **history = NULL;
96 static void linenoiseAtExit(void);
97 int linenoiseHistoryAdd(const char *line);
99 static int isUnsupportedTerm(void) {
100 char *term = getenv("TERM");
103 if (term == NULL) return 0;
104 for (j = 0; unsupported_term[j]; j++)
105 if (!strcasecmp(term,unsupported_term[j])) return 1;
109 static void freeHistory(void) {
113 for (j = 0; j < history_len; j++)
119 static int enableRawMode(int fd) {
122 if (!isatty(STDIN_FILENO)) goto fatal;
123 if (!atexit_registered) {
124 atexit(linenoiseAtExit);
125 atexit_registered = 1;
127 if (tcgetattr(fd,&orig_termios) == -1) goto fatal;
129 raw = orig_termios; /* modify the original mode */
130 /* input modes: no break, no CR to NL, no parity check, no strip char,
131 * no start/stop output control. */
132 raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
133 /* output modes - disable post processing */
134 raw.c_oflag &= ~(OPOST);
135 /* control modes - set 8 bit chars */
136 raw.c_cflag |= (CS8);
137 /* local modes - choing off, canonical off, no extended functions,
138 * no signal chars (^Z,^C) */
139 raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
140 /* control chars - set return condition: min number of bytes and timer.
141 * We want read to return every single byte, without timeout. */
142 raw.c_cc[VMIN] = 1; raw.c_cc[VTIME] = 0; /* 1 byte, no timer */
144 /* put terminal in raw mode after flushing */
145 if (tcsetattr(fd,TCSAFLUSH,&raw) < 0) goto fatal;
154 static void disableRawMode(int fd) {
155 /* Don't even check the return value as it's too late. */
156 if (rawmode && tcsetattr(fd,TCSAFLUSH,&orig_termios) != -1)
160 /* At exit we'll try to fix the terminal to the initial conditions. */
161 static void linenoiseAtExit(void) {
162 disableRawMode(STDIN_FILENO);
166 static int getColumns(void) {
169 if (ioctl(1, TIOCGWINSZ, &ws) == -1) return 80;
173 static void refreshLine(int fd, const char *prompt, char *buf, size_t len, size_t pos, size_t cols) {
175 size_t plen = strlen(prompt);
177 while((plen+pos) >= cols) {
182 while (plen+len > cols) {
186 /* Cursor to left edge */
187 snprintf(seq,64,"\x1b[0G");
188 if (write(fd,seq,strlen(seq)) == -1) return;
189 /* Write the prompt and the current buffer content */
190 if (write(fd,prompt,strlen(prompt)) == -1) return;
191 if (write(fd,buf,len) == -1) return;
193 snprintf(seq,64,"\x1b[0K");
194 if (write(fd,seq,strlen(seq)) == -1) return;
195 /* Move cursor to original position. */
196 snprintf(seq,64,"\x1b[0G\x1b[%dC", (int)(pos+plen));
197 if (write(fd,seq,strlen(seq)) == -1) return;
201 fprintf(stderr, "\x7");
205 static void freeCompletions(linenoiseCompletions *lc) {
207 for (i = 0; i < lc->len; i++)
209 if (lc->cvec != NULL)
213 static int completeLine(int fd, const char *prompt, char *buf, size_t buflen, size_t *len, size_t *pos, size_t cols) {
214 linenoiseCompletions lc = { 0, NULL };
218 completionCallback(buf,&lc);
222 size_t stop = 0, i = 0;
226 /* Show completion or original buffer */
228 clen = strlen(lc.cvec[i]);
229 refreshLine(fd,prompt,lc.cvec[i],clen,clen,cols);
231 refreshLine(fd,prompt,buf,*len,*pos,cols);
234 nread = read(fd,&c,1);
236 freeCompletions(&lc);
242 i = (i+1) % (lc.len+1);
243 if (i == lc.len) beep();
245 case 27: /* escape */
246 /* Re-show original buffer */
248 refreshLine(fd,prompt,buf,*len,*pos,cols);
253 /* Update buffer and return */
255 nwritten = snprintf(buf,buflen,"%s",lc.cvec[i]);
256 *len = *pos = nwritten;
264 freeCompletions(&lc);
265 return c; /* Return last read character */
268 static int linenoisePrompt(int fd, char *buf, size_t buflen, const char *prompt) {
269 size_t plen = strlen(prompt);
272 size_t cols = getColumns();
273 int history_index = 0;
276 buflen--; /* Make sure there is always space for the nulterm */
278 /* The latest history entry is always our current buffer, that
279 * initially is just an empty string. */
280 linenoiseHistoryAdd("");
282 if (write(fd,prompt,plen) == -1) return -1;
286 char seq[2], seq2[2];
288 nread = read(fd,&c,1);
289 if (nread <= 0) return len;
291 /* Only autocomplete when the callback is set. It returns < 0 when
292 * there was an error reading from fd. Otherwise it will return the
293 * character that should be handled next. */
294 if (c == 9 && completionCallback != NULL) {
295 c = completeLine(fd,prompt,buf,buflen,&len,&pos,cols);
296 /* Return on errors */
297 if (c < 0) return len;
298 /* Read next character when 0 */
299 if (c == 0) continue;
306 free(history[history_len]);
307 return (len == 0 && c == 4) ? -1 : (int)len;
311 case 127: /* backspace */
313 if (pos > 0 && len > 0) {
314 memmove(buf+pos-1,buf+pos,len-pos);
318 refreshLine(fd,prompt,buf,len,pos,cols);
321 case 20: /* ctrl-t */
322 if (pos > 0 && pos < len) {
323 int aux = buf[pos-1];
324 buf[pos-1] = buf[pos];
326 if (pos != len-1) pos++;
327 refreshLine(fd,prompt,buf,len,pos,cols);
334 case 16: /* ctrl-p */
337 case 14: /* ctrl-n */
341 case 27: /* escape sequence */
342 if (read(fd,seq,2) == -1) break;
343 if (seq[0] == 91 && seq[1] == 68) {
348 refreshLine(fd,prompt,buf,len,pos,cols);
350 } else if (seq[0] == 91 && seq[1] == 67) {
355 refreshLine(fd,prompt,buf,len,pos,cols);
357 } else if (seq[0] == 91 && (seq[1] == 65 || seq[1] == 66)) {
359 /* up and down arrow: history */
360 if (history_len > 1) {
361 /* Update the current history entry before to
362 * overwrite it with tne next one. */
363 free(history[history_len-1-history_index]);
364 history[history_len-1-history_index] = strdup(buf);
365 /* Show the new entry */
366 history_index += (seq[1] == 65) ? 1 : -1;
367 if (history_index < 0) {
370 } else if (history_index >= history_len) {
371 history_index = history_len-1;
374 strncpy(buf,history[history_len-1-history_index],buflen);
376 len = pos = strlen(buf);
377 refreshLine(fd,prompt,buf,len,pos,cols);
379 } else if (seq[0] == 91 && seq[1] > 48 && seq[1] < 55) {
380 /* extended escape */
381 if (read(fd,seq2,2) == -1) break;
382 if (seq[1] == 51 && seq2[0] == 126) {
384 if (len > 0 && pos < len) {
385 memmove(buf+pos,buf+pos+1,len-pos-1);
388 refreshLine(fd,prompt,buf,len,pos,cols);
400 if (plen+len < cols) {
401 /* Avoid a full update of the line in the
403 if (write(fd,&c,1) == -1) return -1;
405 refreshLine(fd,prompt,buf,len,pos,cols);
408 memmove(buf+pos+1,buf+pos,len-pos);
413 refreshLine(fd,prompt,buf,len,pos,cols);
417 case 21: /* Ctrl+u, delete the whole line. */
420 refreshLine(fd,prompt,buf,len,pos,cols);
422 case 11: /* Ctrl+k, delete from current to end of line. */
425 refreshLine(fd,prompt,buf,len,pos,cols);
427 case 1: /* Ctrl+a, go to the start of the line */
429 refreshLine(fd,prompt,buf,len,pos,cols);
431 case 5: /* ctrl+e, go to the end of the line */
433 refreshLine(fd,prompt,buf,len,pos,cols);
440 static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) {
441 int fd = STDIN_FILENO;
448 if (!isatty(STDIN_FILENO)) {
449 if (fgets(buf, buflen, stdin) == NULL) return -1;
451 if (count && buf[count-1] == '\n') {
456 if (enableRawMode(fd) == -1) return -1;
457 count = linenoisePrompt(fd, buf, buflen, prompt);
464 char *linenoise(const char *prompt) {
465 char buf[LINENOISE_MAX_LINE];
468 if (isUnsupportedTerm()) {
473 if (fgets(buf,LINENOISE_MAX_LINE,stdin) == NULL) return NULL;
475 while(len && (buf[len-1] == '\n' || buf[len-1] == '\r')) {
481 count = linenoiseRaw(buf,LINENOISE_MAX_LINE,prompt);
482 if (count == -1) return NULL;
487 /* Register a callback function to be called for tab-completion. */
488 void linenoiseSetCompletionCallback(linenoiseCompletionCallback *fn) {
489 completionCallback = fn;
492 void linenoiseAddCompletion(linenoiseCompletions *lc, char *str) {
493 size_t len = strlen(str);
494 char *copy = malloc(len+1);
495 memcpy(copy,str,len+1);
496 lc->cvec = realloc(lc->cvec,sizeof(char*)*(lc->len+1));
497 lc->cvec[lc->len++] = copy;
500 /* Using a circular buffer is smarter, but a bit more complex to handle. */
501 int linenoiseHistoryAdd(const char *line) {
504 if (history_max_len == 0) return 0;
505 if (history == NULL) {
506 history = malloc(sizeof(char*)*history_max_len);
507 if (history == NULL) return 0;
508 memset(history,0,(sizeof(char*)*history_max_len));
510 linecopy = strdup(line);
511 if (!linecopy) return 0;
512 if (history_len == history_max_len) {
514 memmove(history,history+1,sizeof(char*)*(history_max_len-1));
517 history[history_len] = linecopy;
522 int linenoiseHistorySetMaxLen(int len) {
525 if (len < 1) return 0;
527 int tocopy = history_len;
529 new = malloc(sizeof(char*)*len);
530 if (new == NULL) return 0;
531 if (len < tocopy) tocopy = len;
532 memcpy(new,history+(history_max_len-tocopy), sizeof(char*)*tocopy);
536 history_max_len = len;
537 if (history_len > history_max_len)
538 history_len = history_max_len;
542 /* Save the history in the specified file. On success 0 is returned
543 * otherwise -1 is returned. */
544 int linenoiseHistorySave(char *filename) {
545 FILE *fp = fopen(filename,"w");
548 if (fp == NULL) return -1;
549 for (j = 0; j < history_len; j++)
550 fprintf(fp,"%s\n",history[j]);
555 /* Load the history from the specified file. If the file does not exist
556 * zero is returned and no operation is performed.
558 * If the file exists and the operation succeeded 0 is returned, otherwise
559 * on error -1 is returned. */
560 int linenoiseHistoryLoad(char *filename) {
561 FILE *fp = fopen(filename,"r");
562 char buf[LINENOISE_MAX_LINE];
564 if (fp == NULL) return -1;
566 while (fgets(buf,LINENOISE_MAX_LINE,fp) != NULL) {
569 p = strchr(buf,'\r');
570 if (!p) p = strchr(buf,'\n');
572 linenoiseHistoryAdd(buf);