linenoise-0.4.0: cbits/linenoise.c
/* linenoise.c -- guerrilla line editing library against the idea that a
* line editing lib needs to be 20,000 lines of C code.
*
* You can find the latest source code at:
*
* http://github.com/antirez/linenoise
*
* Does a number of crazy assumptions that happen to be true in 99.9999% of
* the 2010 UNIX computers around.
*
* ------------------------------------------------------------------------
*
* Copyright (c) 2010-2023, Salvatore Sanfilippo <antirez at gmail dot com>
* Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ------------------------------------------------------------------------
*
* References:
* - http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
* - http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html
*
* Todo list:
* - Filter bogus Ctrl+<char> combinations.
* - Win32 support
*
* Bloat:
* - History search like Ctrl+r in readline?
*
* List of escape sequences used by this program, we do everything just
* with three sequences. In order to be so cheap we may have some
* flickering effect with some slow terminal, but the lesser sequences
* the more compatible.
*
* EL (Erase Line)
* Sequence: ESC [ n K
* Effect: if n is 0 or missing, clear from cursor to end of line
* Effect: if n is 1, clear from beginning of line to cursor
* Effect: if n is 2, clear entire line
*
* CUF (CUrsor Forward)
* Sequence: ESC [ n C
* Effect: moves cursor forward n chars
*
* CUB (CUrsor Backward)
* Sequence: ESC [ n D
* Effect: moves cursor backward n chars
*
* The following is used to get the terminal width if getting
* the width with the TIOCGWINSZ ioctl fails
*
* DSR (Device Status Report)
* Sequence: ESC [ 6 n
* Effect: reports the current cusor position as ESC [ n ; m R
* where n is the row and m is the column
*
* When multi line mode is enabled, we also use an additional escape
* sequence. However multi line editing is disabled by default.
*
* CUU (Cursor Up)
* Sequence: ESC [ n A
* Effect: moves cursor up of n chars.
*
* CUD (Cursor Down)
* Sequence: ESC [ n B
* Effect: moves cursor down of n chars.
*
* When linenoiseClearScreen() is called, two additional escape sequences
* are used in order to clear the screen and position the cursor at home
* position.
*
* CUP (Cursor position)
* Sequence: ESC [ H
* Effect: moves the cursor to upper left corner
*
* ED (Erase display)
* Sequence: ESC [ 2 J
* Effect: clear the whole screen
*
*/
#include <termios.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include "linenoise.h"
#define LINENOISE_DEFAULT_HISTORY_MAX_LEN 100
#define LINENOISE_MAX_LINE 4096
static char *unsupported_term[] = {"dumb","cons25","emacs",NULL};
static linenoiseCompletionCallback *completionCallback = NULL;
static linenoiseHintsCallback *hintsCallback = NULL;
static linenoiseFreeHintsCallback *freeHintsCallback = NULL;
static char *linenoiseNoTTY(void);
static void refreshLineWithCompletion(struct linenoiseState *ls, linenoiseCompletions *lc, int flags);
static void refreshLineWithFlags(struct linenoiseState *l, int flags);
static struct termios orig_termios; /* In order to restore at exit.*/
static int maskmode = 0; /* Show "***" instead of input. For passwords. */
static int rawmode = 0; /* For atexit() function to check if restore is needed*/
static int mlmode = 0; /* Multi line mode. Default is single line. */
static int atexit_registered = 0; /* Register atexit just 1 time. */
static int history_max_len = LINENOISE_DEFAULT_HISTORY_MAX_LEN;
static int history_len = 0;
static char **history = NULL;
enum KEY_ACTION{
KEY_NULL = 0, /* NULL */
CTRL_A = 1, /* Ctrl+a */
CTRL_B = 2, /* Ctrl-b */
CTRL_C = 3, /* Ctrl-c */
CTRL_D = 4, /* Ctrl-d */
CTRL_E = 5, /* Ctrl-e */
CTRL_F = 6, /* Ctrl-f */
CTRL_H = 8, /* Ctrl-h */
TAB = 9, /* Tab */
CTRL_K = 11, /* Ctrl+k */
CTRL_L = 12, /* Ctrl+l */
ENTER = 13, /* Enter */
CTRL_N = 14, /* Ctrl-n */
CTRL_P = 16, /* Ctrl-p */
CTRL_T = 20, /* Ctrl-t */
CTRL_U = 21, /* Ctrl+u */
CTRL_W = 23, /* Ctrl+w */
ESC = 27, /* Escape */
BACKSPACE = 127 /* Backspace */
};
static void linenoiseAtExit(void);
int linenoiseHistoryAdd(const char *line);
#define REFRESH_CLEAN (1<<0) // Clean the old prompt from the screen
#define REFRESH_WRITE (1<<1) // Rewrite the prompt on the screen.
#define REFRESH_ALL (REFRESH_CLEAN|REFRESH_WRITE) // Do both.
static void refreshLine(struct linenoiseState *l);
/* Debugging macro. */
#if 0
FILE *lndebug_fp = NULL;
#define lndebug(...) \
do { \
if (lndebug_fp == NULL) { \
lndebug_fp = fopen("/tmp/lndebug.txt","a"); \
fprintf(lndebug_fp, \
"[%d %d %d] p: %d, rows: %d, rpos: %d, max: %d, oldmax: %d\n", \
(int)l->len,(int)l->pos,(int)l->oldpos,plen,rows,rpos, \
(int)l->oldrows,old_rows); \
} \
fprintf(lndebug_fp, ", " __VA_ARGS__); \
fflush(lndebug_fp); \
} while (0)
#else
#define lndebug(fmt, ...)
#endif
/* ======================= Low level terminal handling ====================== */
/* Enable "mask mode". When it is enabled, instead of the input that
* the user is typing, the terminal will just display a corresponding
* number of asterisks, like "****". This is useful for passwords and other
* secrets that should not be displayed. */
void linenoiseMaskModeEnable(void) {
maskmode = 1;
}
/* Disable mask mode. */
void linenoiseMaskModeDisable(void) {
maskmode = 0;
}
/* Set if to use or not the multi line mode. */
void linenoiseSetMultiLine(int ml) {
mlmode = ml;
}
/* Return true if the terminal name is in the list of terminals we know are
* not able to understand basic escape sequences. */
static int isUnsupportedTerm(void) {
char *term = getenv("TERM");
int j;
if (term == NULL) return 0;
for (j = 0; unsupported_term[j]; j++)
if (!strcasecmp(term,unsupported_term[j])) return 1;
return 0;
}
/* Raw mode: 1960 magic shit. */
static int enableRawMode(int fd) {
struct termios raw;
if (!isatty(STDIN_FILENO)) goto fatal;
if (!atexit_registered) {
atexit(linenoiseAtExit);
atexit_registered = 1;
}
if (tcgetattr(fd,&orig_termios) == -1) goto fatal;
raw = orig_termios; /* modify the original mode */
/* input modes: no break, no CR to NL, no parity check, no strip char,
* no start/stop output control. */
raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
/* output modes - disable post processing */
raw.c_oflag &= ~(OPOST);
/* control modes - set 8 bit chars */
raw.c_cflag |= (CS8);
/* local modes - choing off, canonical off, no extended functions,
* no signal chars (^Z,^C) */
raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
/* control chars - set return condition: min number of bytes and timer.
* We want read to return every single byte, without timeout. */
raw.c_cc[VMIN] = 1; raw.c_cc[VTIME] = 0; /* 1 byte, no timer */
/* put terminal in raw mode after flushing */
if (tcsetattr(fd,TCSAFLUSH,&raw) < 0) goto fatal;
rawmode = 1;
return 0;
fatal:
errno = ENOTTY;
return -1;
}
static void disableRawMode(int fd) {
/* Don't even check the return value as it's too late. */
if (rawmode && tcsetattr(fd,TCSAFLUSH,&orig_termios) != -1)
rawmode = 0;
}
/* Use the ESC [6n escape sequence to query the horizontal cursor position
* and return it. On error -1 is returned, on success the position of the
* cursor. */
static int getCursorPosition(int ifd, int ofd) {
char buf[32];
int cols, rows;
unsigned int i = 0;
/* Report cursor location */
if (write(ofd, "\x1b[6n", 4) != 4) return -1;
/* Read the response: ESC [ rows ; cols R */
while (i < sizeof(buf)-1) {
if (read(ifd,buf+i,1) != 1) break;
if (buf[i] == 'R') break;
i++;
}
buf[i] = '\0';
/* Parse it. */
if (buf[0] != ESC || buf[1] != '[') return -1;
if (sscanf(buf+2,"%d;%d",&rows,&cols) != 2) return -1;
return cols;
}
/* Try to get the number of columns in the current terminal, or assume 80
* if it fails. */
static int getColumns(int ifd, int ofd) {
struct winsize ws;
if (ioctl(1, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
/* ioctl() failed. Try to query the terminal itself. */
int start, cols;
/* Get the initial position so we can restore it later. */
start = getCursorPosition(ifd,ofd);
if (start == -1) goto failed;
/* Go to right margin and get position. */
if (write(ofd,"\x1b[999C",6) != 6) goto failed;
cols = getCursorPosition(ifd,ofd);
if (cols == -1) goto failed;
/* Restore position. */
if (cols > start) {
char seq[32];
snprintf(seq,32,"\x1b[%dD",cols-start);
if (write(ofd,seq,strlen(seq)) == -1) {
/* Can't recover... */
}
}
return cols;
} else {
return ws.ws_col;
}
failed:
return 80;
}
/* Clear the screen. Used to handle ctrl+l */
void linenoiseClearScreen(void) {
if (write(STDOUT_FILENO,"\x1b[H\x1b[2J",7) <= 0) {
/* nothing to do, just to avoid warning. */
}
}
/* Beep, used for completion when there is nothing to complete or when all
* the choices were already shown. */
static void linenoiseBeep(void) {
fprintf(stderr, "\x7");
fflush(stderr);
}
/* ============================== Completion ================================ */
/* Free a list of completion option populated by linenoiseAddCompletion(). */
static void freeCompletions(linenoiseCompletions *lc) {
size_t i;
for (i = 0; i < lc->len; i++)
free(lc->cvec[i]);
if (lc->cvec != NULL)
free(lc->cvec);
}
/* Called by completeLine() and linenoiseShow() to render the current
* edited line with the proposed completion. If the current completion table
* is already available, it is passed as second argument, otherwise the
* function will use the callback to obtain it.
*
* Flags are the same as refreshLine*(), that is REFRESH_* macros. */
static void refreshLineWithCompletion(struct linenoiseState *ls, linenoiseCompletions *lc, int flags) {
/* Obtain the table of completions if the caller didn't provide one. */
linenoiseCompletions ctable = { 0, NULL };
if (lc == NULL) {
completionCallback(ls->buf,&ctable);
lc = &ctable;
}
/* Show the edited line with completion if possible, or just refresh. */
if (ls->completion_idx < lc->len) {
struct linenoiseState saved = *ls;
ls->len = ls->pos = strlen(lc->cvec[ls->completion_idx]);
ls->buf = lc->cvec[ls->completion_idx];
refreshLineWithFlags(ls,flags);
ls->len = saved.len;
ls->pos = saved.pos;
ls->buf = saved.buf;
} else {
refreshLineWithFlags(ls,flags);
}
/* Free the completions table if needed. */
if (lc != &ctable) freeCompletions(&ctable);
}
/* This is an helper function for linenoiseEdit*() and is called when the
* user types the <tab> key in order to complete the string currently in the
* input.
*
* The state of the editing is encapsulated into the pointed linenoiseState
* structure as described in the structure definition.
*
* If the function returns non-zero, the caller should handle the
* returned value as a byte read from the standard input, and process
* it as usually: this basically means that the function may return a byte
* read from the termianl but not processed. Otherwise, if zero is returned,
* the input was consumed by the completeLine() function to navigate the
* possible completions, and the caller should read for the next characters
* from stdin. */
static int completeLine(struct linenoiseState *ls, int keypressed) {
linenoiseCompletions lc = { 0, NULL };
int nwritten;
char c = keypressed;
completionCallback(ls->buf,&lc);
if (lc.len == 0) {
linenoiseBeep();
ls->in_completion = 0;
} else {
switch(c) {
case 9: /* tab */
if (ls->in_completion == 0) {
ls->in_completion = 1;
ls->completion_idx = 0;
} else {
ls->completion_idx = (ls->completion_idx+1) % (lc.len+1);
if (ls->completion_idx == lc.len) linenoiseBeep();
}
c = 0;
break;
case 27: /* escape */
/* Re-show original buffer */
if (ls->completion_idx < lc.len) refreshLine(ls);
ls->in_completion = 0;
c = 0;
break;
default:
/* Update buffer and return */
if (ls->completion_idx < lc.len) {
nwritten = snprintf(ls->buf,ls->buflen,"%s",
lc.cvec[ls->completion_idx]);
ls->len = ls->pos = nwritten;
}
ls->in_completion = 0;
break;
}
/* Show completion or original buffer */
if (ls->in_completion && ls->completion_idx < lc.len) {
refreshLineWithCompletion(ls,&lc,REFRESH_ALL);
} else {
refreshLine(ls);
}
}
freeCompletions(&lc);
return c; /* Return last read character */
}
/* Register a callback function to be called for tab-completion. */
void linenoiseSetCompletionCallback(linenoiseCompletionCallback *fn) {
completionCallback = fn;
}
/* Register a hits function to be called to show hits to the user at the
* right of the prompt. */
void linenoiseSetHintsCallback(linenoiseHintsCallback *fn) {
hintsCallback = fn;
}
/* Register a function to free the hints returned by the hints callback
* registered with linenoiseSetHintsCallback(). */
void linenoiseSetFreeHintsCallback(linenoiseFreeHintsCallback *fn) {
freeHintsCallback = fn;
}
/* This function is used by the callback function registered by the user
* in order to add completion options given the input string when the
* user typed <tab>. See the example.c source code for a very easy to
* understand example. */
void linenoiseAddCompletion(linenoiseCompletions *lc, const char *str) {
size_t len = strlen(str);
char *copy, **cvec;
copy = malloc(len+1);
if (copy == NULL) return;
memcpy(copy,str,len+1);
cvec = realloc(lc->cvec,sizeof(char*)*(lc->len+1));
if (cvec == NULL) {
free(copy);
return;
}
lc->cvec = cvec;
lc->cvec[lc->len++] = copy;
}
/* =========================== Line editing ================================= */
/* We define a very simple "append buffer" structure, that is an heap
* allocated string where we can append to. This is useful in order to
* write all the escape sequences in a buffer and flush them to the standard
* output in a single call, to avoid flickering effects. */
struct abuf {
char *b;
int len;
};
static void abInit(struct abuf *ab) {
ab->b = NULL;
ab->len = 0;
}
static void abAppend(struct abuf *ab, const char *s, int len) {
char *new = realloc(ab->b,ab->len+len);
if (new == NULL) return;
memcpy(new+ab->len,s,len);
ab->b = new;
ab->len += len;
}
static void abFree(struct abuf *ab) {
free(ab->b);
}
/* Helper of refreshSingleLine() and refreshMultiLine() to show hints
* to the right of the prompt. */
void refreshShowHints(struct abuf *ab, struct linenoiseState *l, int plen) {
char seq[64];
if (hintsCallback && plen+l->len < l->cols) {
int color = -1, bold = 0;
char *hint = hintsCallback(l->buf,&color,&bold);
if (hint) {
int hintlen = strlen(hint);
int hintmaxlen = l->cols-(plen+l->len);
if (hintlen > hintmaxlen) hintlen = hintmaxlen;
if (bold == 1 && color == -1) color = 37;
if (color != -1 || bold != 0)
snprintf(seq,64,"\033[%d;%d;49m",bold,color);
else
seq[0] = '\0';
abAppend(ab,seq,strlen(seq));
abAppend(ab,hint,hintlen);
if (color != -1 || bold != 0)
abAppend(ab,"\033[0m",4);
/* Call the function to free the hint returned. */
if (freeHintsCallback) freeHintsCallback(hint);
}
}
}
/* Single line low level line refresh.
*
* Rewrite the currently edited line accordingly to the buffer content,
* cursor position, and number of columns of the terminal.
*
* Flags is REFRESH_* macros. The function can just remove the old
* prompt, just write it, or both. */
static void refreshSingleLine(struct linenoiseState *l, int flags) {
char seq[64];
size_t plen = strlen(l->prompt);
int fd = l->ofd;
char *buf = l->buf;
size_t len = l->len;
size_t pos = l->pos;
struct abuf ab;
while((plen+pos) >= l->cols) {
buf++;
len--;
pos--;
}
while (plen+len > l->cols) {
len--;
}
abInit(&ab);
/* Cursor to left edge */
snprintf(seq,sizeof(seq),"\r");
abAppend(&ab,seq,strlen(seq));
if (flags & REFRESH_WRITE) {
/* Write the prompt and the current buffer content */
abAppend(&ab,l->prompt,strlen(l->prompt));
if (maskmode == 1) {
while (len--) abAppend(&ab,"*",1);
} else {
abAppend(&ab,buf,len);
}
/* Show hits if any. */
refreshShowHints(&ab,l,plen);
}
/* Erase to right */
snprintf(seq,sizeof(seq),"\x1b[0K");
abAppend(&ab,seq,strlen(seq));
if (flags & REFRESH_WRITE) {
/* Move cursor to original position. */
snprintf(seq,sizeof(seq),"\r\x1b[%dC", (int)(pos+plen));
abAppend(&ab,seq,strlen(seq));
}
if (write(fd,ab.b,ab.len) == -1) {} /* Can't recover from write error. */
abFree(&ab);
}
/* Multi line low level line refresh.
*
* Rewrite the currently edited line accordingly to the buffer content,
* cursor position, and number of columns of the terminal.
*
* Flags is REFRESH_* macros. The function can just remove the old
* prompt, just write it, or both. */
static void refreshMultiLine(struct linenoiseState *l, int flags) {
char seq[64];
int plen = strlen(l->prompt);
int rows = (plen+l->len+l->cols-1)/l->cols; /* rows used by current buf. */
int rpos = (plen+l->oldpos+l->cols)/l->cols; /* cursor relative row. */
int rpos2; /* rpos after refresh. */
int col; /* colum position, zero-based. */
int old_rows = l->oldrows;
int fd = l->ofd, j;
struct abuf ab;
l->oldrows = rows;
/* First step: clear all the lines used before. To do so start by
* going to the last row. */
abInit(&ab);
if (flags & REFRESH_CLEAN) {
if (old_rows-rpos > 0) {
lndebug("go down %d", old_rows-rpos);
snprintf(seq,64,"\x1b[%dB", old_rows-rpos);
abAppend(&ab,seq,strlen(seq));
}
/* Now for every row clear it, go up. */
for (j = 0; j < old_rows-1; j++) {
lndebug("clear+up");
snprintf(seq,64,"\r\x1b[0K\x1b[1A");
abAppend(&ab,seq,strlen(seq));
}
}
if (flags & REFRESH_ALL) {
/* Clean the top line. */
lndebug("clear");
snprintf(seq,64,"\r\x1b[0K");
abAppend(&ab,seq,strlen(seq));
}
if (flags & REFRESH_WRITE) {
/* Write the prompt and the current buffer content */
abAppend(&ab,l->prompt,strlen(l->prompt));
if (maskmode == 1) {
unsigned int i;
for (i = 0; i < l->len; i++) abAppend(&ab,"*",1);
} else {
abAppend(&ab,l->buf,l->len);
}
/* Show hits if any. */
refreshShowHints(&ab,l,plen);
/* If we are at the very end of the screen with our prompt, we need to
* emit a newline and move the prompt to the first column. */
if (l->pos &&
l->pos == l->len &&
(l->pos+plen) % l->cols == 0)
{
lndebug("<newline>");
abAppend(&ab,"\n",1);
snprintf(seq,64,"\r");
abAppend(&ab,seq,strlen(seq));
rows++;
if (rows > (int)l->oldrows) l->oldrows = rows;
}
/* Move cursor to right position. */
rpos2 = (plen+l->pos+l->cols)/l->cols; /* Current cursor relative row */
lndebug("rpos2 %d", rpos2);
/* Go up till we reach the expected positon. */
if (rows-rpos2 > 0) {
lndebug("go-up %d", rows-rpos2);
snprintf(seq,64,"\x1b[%dA", rows-rpos2);
abAppend(&ab,seq,strlen(seq));
}
/* Set column. */
col = (plen+(int)l->pos) % (int)l->cols;
lndebug("set col %d", 1+col);
if (col)
snprintf(seq,64,"\r\x1b[%dC", col);
else
snprintf(seq,64,"\r");
abAppend(&ab,seq,strlen(seq));
}
lndebug("\n");
l->oldpos = l->pos;
if (write(fd,ab.b,ab.len) == -1) {} /* Can't recover from write error. */
abFree(&ab);
}
/* Calls the two low level functions refreshSingleLine() or
* refreshMultiLine() according to the selected mode. */
static void refreshLineWithFlags(struct linenoiseState *l, int flags) {
if (mlmode)
refreshMultiLine(l,flags);
else
refreshSingleLine(l,flags);
}
/* Utility function to avoid specifying REFRESH_ALL all the times. */
static void refreshLine(struct linenoiseState *l) {
refreshLineWithFlags(l,REFRESH_ALL);
}
/* Hide the current line, when using the multiplexing API. */
void linenoiseHide(struct linenoiseState *l) {
if (mlmode)
refreshMultiLine(l,REFRESH_CLEAN);
else
refreshSingleLine(l,REFRESH_CLEAN);
}
/* Show the current line, when using the multiplexing API. */
void linenoiseShow(struct linenoiseState *l) {
if (l->in_completion) {
refreshLineWithCompletion(l,NULL,REFRESH_WRITE);
} else {
refreshLineWithFlags(l,REFRESH_WRITE);
}
}
/* Insert the character 'c' at cursor current position.
*
* On error writing to the terminal -1 is returned, otherwise 0. */
int linenoiseEditInsert(struct linenoiseState *l, char c) {
if (l->len < l->buflen) {
if (l->len == l->pos) {
l->buf[l->pos] = c;
l->pos++;
l->len++;
l->buf[l->len] = '\0';
if ((!mlmode && l->plen+l->len < l->cols && !hintsCallback)) {
/* Avoid a full update of the line in the
* trivial case. */
char d = (maskmode==1) ? '*' : c;
if (write(l->ofd,&d,1) == -1) return -1;
} else {
refreshLine(l);
}
} else {
memmove(l->buf+l->pos+1,l->buf+l->pos,l->len-l->pos);
l->buf[l->pos] = c;
l->len++;
l->pos++;
l->buf[l->len] = '\0';
refreshLine(l);
}
}
return 0;
}
/* Move cursor on the left. */
void linenoiseEditMoveLeft(struct linenoiseState *l) {
if (l->pos > 0) {
l->pos--;
refreshLine(l);
}
}
/* Move cursor on the right. */
void linenoiseEditMoveRight(struct linenoiseState *l) {
if (l->pos != l->len) {
l->pos++;
refreshLine(l);
}
}
/* Move cursor to the start of the line. */
void linenoiseEditMoveHome(struct linenoiseState *l) {
if (l->pos != 0) {
l->pos = 0;
refreshLine(l);
}
}
/* Move cursor to the end of the line. */
void linenoiseEditMoveEnd(struct linenoiseState *l) {
if (l->pos != l->len) {
l->pos = l->len;
refreshLine(l);
}
}
/* Substitute the currently edited line with the next or previous history
* entry as specified by 'dir'. */
#define LINENOISE_HISTORY_NEXT 0
#define LINENOISE_HISTORY_PREV 1
void linenoiseEditHistoryNext(struct linenoiseState *l, int dir) {
if (history_len > 1) {
/* Update the current history entry before to
* overwrite it with the next one. */
free(history[history_len - 1 - l->history_index]);
history[history_len - 1 - l->history_index] = strdup(l->buf);
/* Show the new entry */
l->history_index += (dir == LINENOISE_HISTORY_PREV) ? 1 : -1;
if (l->history_index < 0) {
l->history_index = 0;
return;
} else if (l->history_index >= history_len) {
l->history_index = history_len-1;
return;
}
strncpy(l->buf,history[history_len - 1 - l->history_index],l->buflen);
l->buf[l->buflen-1] = '\0';
l->len = l->pos = strlen(l->buf);
refreshLine(l);
}
}
/* Delete the character at the right of the cursor without altering the cursor
* position. Basically this is what happens with the "Delete" keyboard key. */
void linenoiseEditDelete(struct linenoiseState *l) {
if (l->len > 0 && l->pos < l->len) {
memmove(l->buf+l->pos,l->buf+l->pos+1,l->len-l->pos-1);
l->len--;
l->buf[l->len] = '\0';
refreshLine(l);
}
}
/* Backspace implementation. */
void linenoiseEditBackspace(struct linenoiseState *l) {
if (l->pos > 0 && l->len > 0) {
memmove(l->buf+l->pos-1,l->buf+l->pos,l->len-l->pos);
l->pos--;
l->len--;
l->buf[l->len] = '\0';
refreshLine(l);
}
}
/* Delete the previosu word, maintaining the cursor at the start of the
* current word. */
void linenoiseEditDeletePrevWord(struct linenoiseState *l) {
size_t old_pos = l->pos;
size_t diff;
while (l->pos > 0 && l->buf[l->pos-1] == ' ')
l->pos--;
while (l->pos > 0 && l->buf[l->pos-1] != ' ')
l->pos--;
diff = old_pos - l->pos;
memmove(l->buf+l->pos,l->buf+old_pos,l->len-old_pos+1);
l->len -= diff;
refreshLine(l);
}
/* This function is part of the multiplexed API of Linenoise, that is used
* in order to implement the blocking variant of the API but can also be
* called by the user directly in an event driven program. It will:
*
* 1. Initialize the linenoise state passed by the user.
* 2. Put the terminal in RAW mode.
* 3. Show the prompt.
* 4. Return control to the user, that will have to call linenoiseEditFeed()
* each time there is some data arriving in the standard input.
*
* The user can also call linenoiseEditHide() and linenoiseEditShow() if it
* is required to show some input arriving asyncronously, without mixing
* it with the currently edited line.
*
* When linenoiseEditFeed() returns non-NULL, the user finished with the
* line editing session (pressed enter CTRL-D/C): in this case the caller
* needs to call linenoiseEditStop() to put back the terminal in normal
* mode. This will not destroy the buffer, as long as the linenoiseState
* is still valid in the context of the caller.
*
* The function returns 0 on success, or -1 if writing to standard output
* fails. If stdin_fd or stdout_fd are set to -1, the default is to use
* STDIN_FILENO and STDOUT_FILENO.
*/
int linenoiseEditStart(struct linenoiseState *l, int stdin_fd, int stdout_fd, char *buf, size_t buflen, const char *prompt) {
/* Populate the linenoise state that we pass to functions implementing
* specific editing functionalities. */
l->in_completion = 0;
l->ifd = stdin_fd != -1 ? stdin_fd : STDIN_FILENO;
l->ofd = stdout_fd != -1 ? stdout_fd : STDOUT_FILENO;
l->buf = buf;
l->buflen = buflen;
l->prompt = prompt;
l->plen = strlen(prompt);
l->oldpos = l->pos = 0;
l->len = 0;
l->cols = getColumns(stdin_fd, stdout_fd);
l->oldrows = 0;
l->history_index = 0;
/* Buffer starts empty. */
l->buf[0] = '\0';
l->buflen--; /* Make sure there is always space for the nulterm */
/* If stdin is not a tty, stop here with the initialization. We
* will actually just read a line from standard input in blocking
* mode later, in linenoiseEditFeed(). */
if (!isatty(l->ifd)) return 0;
/* Enter raw mode. */
if (enableRawMode(l->ifd) == -1) return -1;
/* The latest history entry is always our current buffer, that
* initially is just an empty string. */
linenoiseHistoryAdd("");
if (write(l->ofd,prompt,l->plen) == -1) return -1;
return 0;
}
char *linenoiseEditMore = "If you see this, you are misusing the API: when linenoiseEditFeed() is called, if it returns linenoiseEditMore the user is yet editing the line. See the README file for more information.";
/* This function is part of the multiplexed API of linenoise, see the top
* comment on linenoiseEditStart() for more information. Call this function
* each time there is some data to read from the standard input file
* descriptor. In the case of blocking operations, this function can just be
* called in a loop, and block.
*
* The function returns linenoiseEditMore to signal that line editing is still
* in progress, that is, the user didn't yet pressed enter / CTRL-D. Otherwise
* the function returns the pointer to the heap-allocated buffer with the
* edited line, that the user should free with linenoiseFree().
*
* On special conditions, NULL is returned and errno is populated:
*
* EAGAIN if the user pressed Ctrl-C
* ENOENT if the user pressed Ctrl-D
*
* Some other errno: I/O error.
*/
char *linenoiseEditFeed(struct linenoiseState *l) {
/* Not a TTY, pass control to line reading without character
* count limits. */
if (!isatty(l->ifd)) return linenoiseNoTTY();
char c;
int nread;
char seq[3];
nread = read(l->ifd,&c,1);
if (nread <= 0) return NULL;
/* Only autocomplete when the callback is set. It returns < 0 when
* there was an error reading from fd. Otherwise it will return the
* character that should be handled next. */
if ((l->in_completion || c == 9) && completionCallback != NULL) {
c = completeLine(l,c);
/* Return on errors */
if (c < 0) return NULL;
/* Read next character when 0 */
if (c == 0) return linenoiseEditMore;
}
switch(c) {
case ENTER: /* enter */
history_len--;
free(history[history_len]);
if (mlmode) linenoiseEditMoveEnd(l);
if (hintsCallback) {
/* Force a refresh without hints to leave the previous
* line as the user typed it after a newline. */
linenoiseHintsCallback *hc = hintsCallback;
hintsCallback = NULL;
refreshLine(l);
hintsCallback = hc;
}
return strdup(l->buf);
case CTRL_C: /* ctrl-c */
errno = EAGAIN;
return NULL;
case BACKSPACE: /* backspace */
case 8: /* ctrl-h */
linenoiseEditBackspace(l);
break;
case CTRL_D: /* ctrl-d, remove char at right of cursor, or if the
line is empty, act as end-of-file. */
if (l->len > 0) {
linenoiseEditDelete(l);
} else {
history_len--;
free(history[history_len]);
errno = ENOENT;
return NULL;
}
break;
case CTRL_T: /* ctrl-t, swaps current character with previous. */
if (l->pos > 0 && l->pos < l->len) {
int aux = l->buf[l->pos-1];
l->buf[l->pos-1] = l->buf[l->pos];
l->buf[l->pos] = aux;
if (l->pos != l->len-1) l->pos++;
refreshLine(l);
}
break;
case CTRL_B: /* ctrl-b */
linenoiseEditMoveLeft(l);
break;
case CTRL_F: /* ctrl-f */
linenoiseEditMoveRight(l);
break;
case CTRL_P: /* ctrl-p */
linenoiseEditHistoryNext(l, LINENOISE_HISTORY_PREV);
break;
case CTRL_N: /* ctrl-n */
linenoiseEditHistoryNext(l, LINENOISE_HISTORY_NEXT);
break;
case ESC: /* escape sequence */
/* Read the next two bytes representing the escape sequence.
* Use two calls to handle slow terminals returning the two
* chars at different times. */
if (read(l->ifd,seq,1) == -1) break;
if (read(l->ifd,seq+1,1) == -1) break;
/* ESC [ sequences. */
if (seq[0] == '[') {
if (seq[1] >= '0' && seq[1] <= '9') {
/* Extended escape, read additional byte. */
if (read(l->ifd,seq+2,1) == -1) break;
if (seq[2] == '~') {
switch(seq[1]) {
case '3': /* Delete key. */
linenoiseEditDelete(l);
break;
}
}
} else {
switch(seq[1]) {
case 'A': /* Up */
linenoiseEditHistoryNext(l, LINENOISE_HISTORY_PREV);
break;
case 'B': /* Down */
linenoiseEditHistoryNext(l, LINENOISE_HISTORY_NEXT);
break;
case 'C': /* Right */
linenoiseEditMoveRight(l);
break;
case 'D': /* Left */
linenoiseEditMoveLeft(l);
break;
case 'H': /* Home */
linenoiseEditMoveHome(l);
break;
case 'F': /* End*/
linenoiseEditMoveEnd(l);
break;
}
}
}
/* ESC O sequences. */
else if (seq[0] == 'O') {
switch(seq[1]) {
case 'H': /* Home */
linenoiseEditMoveHome(l);
break;
case 'F': /* End*/
linenoiseEditMoveEnd(l);
break;
}
}
break;
default:
if (linenoiseEditInsert(l,c)) return NULL;
break;
case CTRL_U: /* Ctrl+u, delete the whole line. */
l->buf[0] = '\0';
l->pos = l->len = 0;
refreshLine(l);
break;
case CTRL_K: /* Ctrl+k, delete from current to end of line. */
l->buf[l->pos] = '\0';
l->len = l->pos;
refreshLine(l);
break;
case CTRL_A: /* Ctrl+a, go to the start of the line */
linenoiseEditMoveHome(l);
break;
case CTRL_E: /* ctrl+e, go to the end of the line */
linenoiseEditMoveEnd(l);
break;
case CTRL_L: /* ctrl+l, clear screen */
linenoiseClearScreen();
refreshLine(l);
break;
case CTRL_W: /* ctrl+w, delete previous word */
linenoiseEditDeletePrevWord(l);
break;
}
return linenoiseEditMore;
}
/* This is part of the multiplexed linenoise API. See linenoiseEditStart()
* for more information. This function is called when linenoiseEditFeed()
* returns something different than NULL. At this point the user input
* is in the buffer, and we can restore the terminal in normal mode. */
void linenoiseEditStop(struct linenoiseState *l) {
if (!isatty(l->ifd)) return;
disableRawMode(l->ifd);
printf("\n");
}
/* This just implements a blocking loop for the multiplexed API.
* In many applications that are not event-drivern, we can just call
* the blocking linenoise API, wait for the user to complete the editing
* and return the buffer. */
static char *linenoiseBlockingEdit(int stdin_fd, int stdout_fd, char *buf, size_t buflen, const char *prompt)
{
struct linenoiseState l;
/* Editing without a buffer is invalid. */
if (buflen == 0) {
errno = EINVAL;
return NULL;
}
linenoiseEditStart(&l,stdin_fd,stdout_fd,buf,buflen,prompt);
char *res;
while((res = linenoiseEditFeed(&l)) == linenoiseEditMore);
linenoiseEditStop(&l);
return res;
}
/* This special mode is used by linenoise in order to print scan codes
* on screen for debugging / development purposes. It is implemented
* by the linenoise_example program using the --keycodes option. */
void linenoisePrintKeyCodes(void) {
char quit[4];
printf("Linenoise key codes debugging mode.\n"
"Press keys to see scan codes. Type 'quit' at any time to exit.\n");
if (enableRawMode(STDIN_FILENO) == -1) return;
memset(quit,' ',4);
while(1) {
char c;
int nread;
nread = read(STDIN_FILENO,&c,1);
if (nread <= 0) continue;
memmove(quit,quit+1,sizeof(quit)-1); /* shift string to left. */
quit[sizeof(quit)-1] = c; /* Insert current char on the right. */
if (memcmp(quit,"quit",sizeof(quit)) == 0) break;
printf("'%c' %02x (%d) (type quit to exit)\n",
isprint(c) ? c : '?', (int)c, (int)c);
printf("\r"); /* Go left edge manually, we are in raw mode. */
fflush(stdout);
}
disableRawMode(STDIN_FILENO);
}
/* This function is called when linenoise() is called with the standard
* input file descriptor not attached to a TTY. So for example when the
* program using linenoise is called in pipe or with a file redirected
* to its standard input. In this case, we want to be able to return the
* line regardless of its length (by default we are limited to 4k). */
static char *linenoiseNoTTY(void) {
char *line = NULL;
size_t len = 0, maxlen = 0;
while(1) {
if (len == maxlen) {
if (maxlen == 0) maxlen = 16;
maxlen *= 2;
char *oldval = line;
line = realloc(line,maxlen);
if (line == NULL) {
if (oldval) free(oldval);
return NULL;
}
}
int c = fgetc(stdin);
if (c == EOF || c == '\n') {
if (c == EOF && len == 0) {
free(line);
return NULL;
} else {
line[len] = '\0';
return line;
}
} else {
line[len] = c;
len++;
}
}
}
/* The high level function that is the main API of the linenoise library.
* This function checks if the terminal has basic capabilities, just checking
* for a blacklist of stupid terminals, and later either calls the line
* editing function or uses dummy fgets() so that you will be able to type
* something even in the most desperate of the conditions. */
char *linenoise(const char *prompt) {
char buf[LINENOISE_MAX_LINE];
if (!isatty(STDIN_FILENO)) {
/* Not a tty: read from file / pipe. In this mode we don't want any
* limit to the line size, so we call a function to handle that. */
return linenoiseNoTTY();
} else if (isUnsupportedTerm()) {
size_t len;
printf("%s",prompt);
fflush(stdout);
if (fgets(buf,LINENOISE_MAX_LINE,stdin) == NULL) return NULL;
len = strlen(buf);
while(len && (buf[len-1] == '\n' || buf[len-1] == '\r')) {
len--;
buf[len] = '\0';
}
return strdup(buf);
} else {
char *retval = linenoiseBlockingEdit(STDIN_FILENO,STDOUT_FILENO,buf,LINENOISE_MAX_LINE,prompt);
return retval;
}
}
/* This is just a wrapper the user may want to call in order to make sure
* the linenoise returned buffer is freed with the same allocator it was
* created with. Useful when the main program is using an alternative
* allocator. */
void linenoiseFree(void *ptr) {
if (ptr == linenoiseEditMore) return; // Protect from API misuse.
free(ptr);
}
/* ================================ History ================================= */
/* Free the history, but does not reset it. Only used when we have to
* exit() to avoid memory leaks are reported by valgrind & co. */
static void freeHistory(void) {
if (history) {
int j;
for (j = 0; j < history_len; j++)
free(history[j]);
free(history);
}
}
/* At exit we'll try to fix the terminal to the initial conditions. */
static void linenoiseAtExit(void) {
disableRawMode(STDIN_FILENO);
freeHistory();
}
/* This is the API call to add a new entry in the linenoise history.
* It uses a fixed array of char pointers that are shifted (memmoved)
* when the history max length is reached in order to remove the older
* entry and make room for the new one, so it is not exactly suitable for huge
* histories, but will work well for a few hundred of entries.
*
* Using a circular buffer is smarter, but a bit more complex to handle. */
int linenoiseHistoryAdd(const char *line) {
char *linecopy;
if (history_max_len == 0) return 0;
/* Initialization on first call. */
if (history == NULL) {
history = malloc(sizeof(char*)*history_max_len);
if (history == NULL) return 0;
memset(history,0,(sizeof(char*)*history_max_len));
}
/* Don't add duplicated lines. */
if (history_len && !strcmp(history[history_len-1], line)) return 0;
/* Add an heap allocated copy of the line in the history.
* If we reached the max length, remove the older line. */
linecopy = strdup(line);
if (!linecopy) return 0;
if (history_len == history_max_len) {
free(history[0]);
memmove(history,history+1,sizeof(char*)*(history_max_len-1));
history_len--;
}
history[history_len] = linecopy;
history_len++;
return 1;
}
/* Set the maximum length for the history. This function can be called even
* if there is already some history, the function will make sure to retain
* just the latest 'len' elements if the new history length value is smaller
* than the amount of items already inside the history. */
int linenoiseHistorySetMaxLen(int len) {
char **new;
if (len < 1) return 0;
if (history) {
int tocopy = history_len;
new = malloc(sizeof(char*)*len);
if (new == NULL) return 0;
/* If we can't copy everything, free the elements we'll not use. */
if (len < tocopy) {
int j;
for (j = 0; j < tocopy-len; j++) free(history[j]);
tocopy = len;
}
memset(new,0,sizeof(char*)*len);
memcpy(new,history+(history_len-tocopy), sizeof(char*)*tocopy);
free(history);
history = new;
}
history_max_len = len;
if (history_len > history_max_len)
history_len = history_max_len;
return 1;
}
/* Save the history in the specified file. On success 0 is returned
* otherwise -1 is returned. */
int linenoiseHistorySave(const char *filename) {
mode_t old_umask = umask(S_IXUSR|S_IRWXG|S_IRWXO);
FILE *fp;
int j;
fp = fopen(filename,"w");
umask(old_umask);
if (fp == NULL) return -1;
chmod(filename,S_IRUSR|S_IWUSR);
for (j = 0; j < history_len; j++)
fprintf(fp,"%s\n",history[j]);
fclose(fp);
return 0;
}
/* Load the history from the specified file. If the file does not exist
* zero is returned and no operation is performed.
*
* If the file exists and the operation succeeded 0 is returned, otherwise
* on error -1 is returned. */
int linenoiseHistoryLoad(const char *filename) {
FILE *fp = fopen(filename,"r");
char buf[LINENOISE_MAX_LINE];
if (fp == NULL) return -1;
while (fgets(buf,LINENOISE_MAX_LINE,fp) != NULL) {
char *p;
p = strchr(buf,'\r');
if (!p) p = strchr(buf,'\n');
if (p) *p = '\0';
linenoiseHistoryAdd(buf);
}
fclose(fp);
return 0;
}