diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,29 @@ +Copyright (c) 2010-2013, Salvatore Sanfilippo +Copyright (c) 2010-2013, Pieter Noordhuis +Copyright (c) 2014-2017, Stephen Diehl +Copyright (c) 2019, Eric Conlon + +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. diff --git a/README.md b/README.md new file mode 100644 --- /dev/null +++ b/README.md @@ -0,0 +1,44 @@ +# linenoise + +[![CircleCI](https://circleci.com/gh/ejconlon/haskell-linenoise/tree/master.svg?style=svg)](https://circleci.com/gh/ejconlon/haskell-linenoise/tree/master) + +A lightweight readline-replacement library for Haskell based on the `linenoise` library. (Not production ready!) +See the [demo app](https://github.com/ejconlon/haskell-linenoise/blob/master/app/Main.hs) for usage, or see the [climb](https://github.com/ejconlon/climb) library for higher-level building blocks for GHCi-like REPLs with colon-commands. + +## Differences from alternatives + +* `haskeline` + * This uses FFI to a minimal C library vs pure Haskell + * This uses standard MTL/Unlift typeclasses vs custom ones. + * This does not require the use of a specific monad transformer. +* `readline` + * This offers a `MonadIO/MonadUnliftIO` interface vs raw `IO`. + * This vendors and statically links its underlying library to simplify the build process. + +## License and attribution + +This library includes the source code and license for `linenoise` in `cbits`. +It is a fork of an older [library](https://github.com/sdiehl/haskell-linenoise) with all licensing and +attribution preserved. + +## Development workflow + +This project uses `stack` to build. + +The `Makefile` has a bunch of relevant phony targets for a development workflow including + +* `build` - Build the library and demo +* `download` - Update vendored `linenoise` +* `demo` - Run the demo app +* `deps` - Install dev tools +* `lint` - Lint with `hlint` +* `format` - Format with `stylish-haskell` +* `docs` - Generate docs + +In addition, there are targets starting with `ci` that are invoked in various CI phases. + +## TODO + +* Support unicode (may involve vendoring a `linenoise` [fork](https://github.com/yhirose/linenoise/tree/utf8-support)) +* Verify that the FFI modifications for `ByteString` are memory-safe +* Upload to Hackage diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/app/Main.hs b/app/Main.hs new file mode 100644 --- /dev/null +++ b/app/Main.hs @@ -0,0 +1,33 @@ +{-# LANGUAGE OverloadedStrings #-} + +module Main (main) where + +import Control.Monad (void) +import Control.Monad.IO.Class (liftIO) +import Control.Monad.State.Strict (get, modify) +import Data.Text (Text) +import qualified Data.Text as Text +import qualified Data.Text.IO as TIO +import Linenoise + +type History = [Text] + +type Repl a = ReplT () History IO a + +runRepl :: Repl a -> History -> IO (a, History) +runRepl n = runReplT n () + +completer :: Text -> Repl [Text] +completer line = filter (Text.isPrefixOf line) <$> get + +action :: Text -> Repl ReplDirective +action x = do + modify (x:) + liftIO (TIO.putStrLn x) + pure ReplContinue + +repl :: Repl () +repl = replM ReplContinue ">>> " action (byWord completer) + +main :: IO () +main = void (runRepl repl []) diff --git a/cbits/linenoise.c b/cbits/linenoise.c new file mode 100644 --- /dev/null +++ b/cbits/linenoise.c @@ -0,0 +1,1201 @@ +/* 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) 2010-2016, Salvatore Sanfilippo + * Copyright (c) 2010-2013, Pieter Noordhuis + * + * 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+ 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#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 struct termios orig_termios; /* In order to restore at exit.*/ +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; + +/* The linenoiseState structure represents the state during line editing. + * We pass this state to functions implementing specific editing + * functionalities. */ +struct linenoiseState { + int ifd; /* Terminal stdin file descriptor. */ + int ofd; /* Terminal stdout file descriptor. */ + char *buf; /* Edited line buffer. */ + size_t buflen; /* Edited line buffer size. */ + const char *prompt; /* Prompt to display. */ + size_t plen; /* Prompt length. */ + size_t pos; /* Current cursor position. */ + size_t oldpos; /* Previous refresh cursor position. */ + size_t len; /* Current edited line length. */ + size_t cols; /* Number of columns in terminal. */ + size_t maxrows; /* Maximum num of rows used so far (multiline mode) */ + int history_index; /* The history index we are currently editing. */ +}; + +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); +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->maxrows,old_rows); \ + } \ + fprintf(lndebug_fp, ", " __VA_ARGS__); \ + fflush(lndebug_fp); \ + } while (0) +#else +#define lndebug(fmt, ...) +#endif + +/* ======================= Low level terminal handling ====================== */ + +/* 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); +} + +/* This is an helper function for linenoiseEdit() and is called when the + * user types the 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. */ +static int completeLine(struct linenoiseState *ls) { + linenoiseCompletions lc = { 0, NULL }; + int nread, nwritten; + char c = 0; + + completionCallback(ls->buf,&lc); + if (lc.len == 0) { + linenoiseBeep(); + } else { + size_t stop = 0, i = 0; + + while(!stop) { + /* Show completion or original buffer */ + if (i < lc.len) { + struct linenoiseState saved = *ls; + + ls->len = ls->pos = strlen(lc.cvec[i]); + ls->buf = lc.cvec[i]; + refreshLine(ls); + ls->len = saved.len; + ls->pos = saved.pos; + ls->buf = saved.buf; + } else { + refreshLine(ls); + } + + nread = read(ls->ifd,&c,1); + if (nread <= 0) { + freeCompletions(&lc); + return -1; + } + + switch(c) { + case 9: /* tab */ + i = (i+1) % (lc.len+1); + if (i == lc.len) linenoiseBeep(); + break; + case 27: /* escape */ + /* Re-show original buffer */ + if (i < lc.len) refreshLine(ls); + stop = 1; + break; + default: + /* Update buffer and return */ + if (i < lc.len) { + nwritten = snprintf(ls->buf,ls->buflen,"%s",lc.cvec[i]); + ls->len = ls->pos = nwritten; + } + stop = 1; + break; + } + } + } + + 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 . 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. */ +static void refreshSingleLine(struct linenoiseState *l) { + 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,64,"\r"); + abAppend(&ab,seq,strlen(seq)); + /* Write the prompt and the current buffer content */ + abAppend(&ab,l->prompt,strlen(l->prompt)); + abAppend(&ab,buf,len); + /* Show hits if any. */ + refreshShowHints(&ab,l,plen); + /* Erase to right */ + snprintf(seq,64,"\x1b[0K"); + abAppend(&ab,seq,strlen(seq)); + /* Move cursor to original position. */ + snprintf(seq,64,"\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. */ +static void refreshMultiLine(struct linenoiseState *l) { + 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->maxrows; + int fd = l->ofd, j; + struct abuf ab; + + /* Update maxrows if needed. */ + if (rows > (int)l->maxrows) l->maxrows = rows; + + /* First step: clear all the lines used before. To do so start by + * going to the last row. */ + abInit(&ab); + 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)); + } + + /* Clean the top line. */ + lndebug("clear"); + snprintf(seq,64,"\r\x1b[0K"); + abAppend(&ab,seq,strlen(seq)); + + /* Write the prompt and the current buffer content */ + abAppend(&ab,l->prompt,strlen(l->prompt)); + 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(""); + abAppend(&ab,"\n",1); + snprintf(seq,64,"\r"); + abAppend(&ab,seq,strlen(seq)); + rows++; + if (rows > (int)l->maxrows) l->maxrows = 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 refreshLine(struct linenoiseState *l) { + if (mlmode) + refreshMultiLine(l); + else + refreshSingleLine(l); +} + +/* 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. */ + if (write(l->ofd,&c,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 the core of the line editing capability of linenoise. + * It expects 'fd' to be already in "raw mode" so that every key pressed + * will be returned ASAP to read(). + * + * The resulting string is put into 'buf' when the user type enter, or + * when ctrl+d is typed. + * + * The function returns the length of the current buffer. */ +static int linenoiseEdit(int stdin_fd, int stdout_fd, char *buf, size_t buflen, const char *prompt) +{ + struct linenoiseState l; + + /* Populate the linenoise state that we pass to functions implementing + * specific editing functionalities. */ + l.ifd = stdin_fd; + l.ofd = stdout_fd; + 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.maxrows = 0; + l.history_index = 0; + + /* Buffer starts empty. */ + l.buf[0] = '\0'; + l.buflen--; /* Make sure there is always space for the nulterm */ + + /* 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; + while(1) { + char c; + int nread; + char seq[3]; + + nread = read(l.ifd,&c,1); + if (nread <= 0) return l.len; + + /* 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 (c == 9 && completionCallback != NULL) { + c = completeLine(&l); + /* Return on errors */ + if (c < 0) return l.len; + /* Read next character when 0 */ + if (c == 0) continue; + } + + 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 (int)l.len; + case CTRL_C: /* ctrl-c */ + errno = EAGAIN; + return -1; + 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]); + return -1; + } + break; + case CTRL_T: /* ctrl-t, swaps current character with previous. */ + if (l.pos > 0 && l.pos < l.len) { + int aux = buf[l.pos-1]; + buf[l.pos-1] = buf[l.pos]; + 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 -1; + break; + case CTRL_U: /* Ctrl+u, delete the whole line. */ + buf[0] = '\0'; + l.pos = l.len = 0; + refreshLine(&l); + break; + case CTRL_K: /* Ctrl+k, delete from current to end of line. */ + 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 l.len; +} + +/* 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 calls the line editing function linenoiseEdit() using + * the STDIN file descriptor set in raw mode. */ +static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) { + int count; + + if (buflen == 0) { + errno = EINVAL; + return -1; + } + + if (enableRawMode(STDIN_FILENO) == -1) return -1; + count = linenoiseEdit(STDIN_FILENO, STDOUT_FILENO, buf, buflen, prompt); + disableRawMode(STDIN_FILENO); + printf("\n"); + return count; +} + +/* 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]; + int count; + + 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 { + count = linenoiseRaw(buf,LINENOISE_MAX_LINE,prompt); + if (count == -1) return NULL; + return strdup(buf); + } +} + +/* 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) { + 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; +} diff --git a/linenoise.cabal b/linenoise.cabal new file mode 100644 --- /dev/null +++ b/linenoise.cabal @@ -0,0 +1,69 @@ +cabal-version: 1.12 + +-- This file has been generated from package.yaml by hpack version 0.31.2. +-- +-- see: https://github.com/sol/hpack +-- +-- hash: 9c5adcaeb5854166e0c083c000d0b95aefa62722036500d6cc7104cdd13c9ea3 + +name: linenoise +version: 0.3.0 +synopsis: A lightweight readline-replacement library for Haskell +description: Please see the README on GitHub at +category: User Interfaces +homepage: https://github.com/ejconlon/haskell-linenoise#readme +bug-reports: https://github.com/ejconlon/haskell-linenoise/issues +author: Stephen Diehl, Eric Conlon +maintainer: ejconlon@gmail.com +copyright: 2014 Stephen Diehl, 2019 Eric Conlon +license: BSD3 +license-file: LICENSE +build-type: Simple +extra-source-files: + README.md + +source-repository head + type: git + location: https://github.com/ejconlon/haskell-linenoise + +library + exposed-modules: + Linenoise + Linenoise.Unlift + Linenoise.Repl + Linenoise.Completion + other-modules: + Linenoise.FFI + Paths_linenoise + hs-source-dirs: + src + ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wpartial-fields -Wredundant-constraints -fno-warn-unused-top-binds + include-dirs: + cbits + c-sources: + cbits/linenoise.c + build-depends: + base >=4.12 && <5 + , bytestring >=0.10 + , exceptions >=0.10 + , mtl >=2.2 + , text >=1.2 + , unliftio-core >=0.1 + default-language: Haskell2010 + +executable linenoise-demo + main-is: Main.hs + other-modules: + Paths_linenoise + hs-source-dirs: + app + ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wpartial-fields -Wredundant-constraints -fno-warn-unused-top-binds -threaded -rtsopts -with-rtsopts=-N + build-depends: + base >=4.12 && <5 + , bytestring >=0.10 + , exceptions >=0.10 + , linenoise + , mtl >=2.2 + , text >=1.2 + , unliftio-core >=0.1 + default-language: Haskell2010 diff --git a/src/Linenoise.hs b/src/Linenoise.hs new file mode 100644 --- /dev/null +++ b/src/Linenoise.hs @@ -0,0 +1,23 @@ +-- | Re-exports of all public entities. +module Linenoise + ( InputResult (..) + , ReplDirective (..) + , ReplT (..) + , addHistory + , byWord + , clearScreen + , getInputLine + , historyLoad + , historySave + , printKeycodes + , replM + , runReplT + , setCompletion + , setMultiline + , stifleHistory + ) where + +import Linenoise.Completion (byWord) +import Linenoise.Repl (ReplDirective (..), ReplT (..), replM, runReplT) +import Linenoise.Unlift (InputResult (..), addHistory, clearScreen, getInputLine, historyLoad, historySave, + printKeycodes, setCompletion, setMultiline, stifleHistory) diff --git a/src/Linenoise/Completion.hs b/src/Linenoise/Completion.hs new file mode 100644 --- /dev/null +++ b/src/Linenoise/Completion.hs @@ -0,0 +1,32 @@ +{-# LANGUAGE OverloadedStrings #-} + +module Linenoise.Completion + ( byWord + ) where + +import Data.Text (Text) +import qualified Data.Text as Text + +-- | Complete by word. +byWord :: Monad m => (Text -> m [Text]) -> (Text -> m [Text]) +byWord f line = do + let split = Text.words line + case split of + [] -> f line + [_] -> f line + sp -> do + let (x,xs) = (last sp, init sp) + res <- f x + case res of + [] -> pure [line] + [y] -> + pure [Text.unwords xs <> " " <> x <> trimComplete x y <> " "] + ys -> + pure (map (complete x xs) ys) + +complete :: Text -> [Text] -> Text -> Text +complete x xs y = + Text.unwords xs <> " " <> x <> trimComplete x y + +trimComplete :: Text -> Text -> Text +trimComplete = Text.drop . Text.length diff --git a/src/Linenoise/FFI.hs b/src/Linenoise/FFI.hs new file mode 100644 --- /dev/null +++ b/src/Linenoise/FFI.hs @@ -0,0 +1,135 @@ +{-# LANGUAGE DeriveFunctor #-} +{-# LANGUAGE DeriveFoldable #-} +{-# LANGUAGE DeriveTraversable #-} +{-# LANGUAGE ForeignFunctionInterface #-} + +-- | Just an FFI layer over the C library. +module Linenoise.FFI + ( InputResult (..) + , addHistory + , clearScreen + , getInputLine + , historyLoad + , historySave + , printKeycodes + , setCompletion + , setMultiline + , stifleHistory + ) where + +import Data.ByteString (ByteString) +import qualified Data.ByteString.Unsafe as BSU +import Data.Foldable (forM_) +import Foreign +import Foreign.C.Error (eAGAIN, getErrno, resetErrno) +import Foreign.C.String +import Foreign.C.Types (CChar, CInt (..), CSize) + +foreign import ccall "linenoise.h linenoise" + linenoise :: CString -> IO CString +foreign import ccall "linenoise.h linenoiseHistoryAdd" + linenoiseHistoryAdd :: Ptr CChar -> IO CInt +foreign import ccall "linenoise.h linenoiseHistorySetMaxLen" + linenoiseHistorySetMaxLen :: CInt -> IO CInt +foreign import ccall "linenoise.h linenoiseHistorySave" + linenoiseHistorySave :: CString -> IO () +foreign import ccall "linenoise.h linenoiseHistoryLoad" + linenoiseHistoryLoad :: CString -> IO () +foreign import ccall "linenoise.h linenoiseClearScreen" + linenoiseClearScreen :: IO () +foreign import ccall "linenoise.h linenoiseSetMultiLine" + linenoiseSetMultiLine :: CInt -> IO () +foreign import ccall "linenoise.h linenoisePrintKeyCodes" + linenoisePrintKeyCodes :: IO () +foreign import ccall "linenoise.h linenoiseSetCompletionCallback" + linenoiseSetCompletionCallback :: FunPtr CompleteFunc -> IO () +foreign import ccall "linenoise.h linenoiseAddCompletion" + linenoiseAddCompletion :: Completion -> CString -> IO () + +foreign import ccall "wrapper" + makeFunPtr :: CompleteFunc -> IO (FunPtr CompleteFunc) + +data CompletionType = CompletionType CSize (Ptr (Ptr CChar)) + deriving (Show, Eq) + +type Completion = Ptr CompletionType + +instance Storable CompletionType where + sizeOf _ = 8 + alignment = sizeOf + peek ptr = do + a <- peekByteOff ptr 0 + b <- peekByteOff ptr 4 + pure (CompletionType a b) + poke = error "no poke" + +-- Completion C callback +type CompleteFunc = (CString -> Completion -> IO ()) + +-- Make a completion function pointer. +makeCompletion :: (ByteString -> IO [ByteString]) -> (CString -> Completion -> IO ()) +makeCompletion f buf lc = do + line <- BSU.unsafePackCString buf + comps <- f line + forM_ comps (`BSU.unsafeUseAsCString` linenoiseAddCompletion lc) + +-- | Result of getInputLine. +data InputResult a + = InterruptResult -- ^ ctrl+c + | EofResult -- ^ ctrl+d + | LineResult !a -- Possibly empty line. + deriving (Eq, Show, Functor, Foldable, Traversable) + +-- | Run the prompt, yielding a string. +getInputLine :: ByteString -> IO (InputResult ByteString) +getInputLine prompt = do + res <- BSU.unsafeUseAsCString prompt $ \str -> do + ptr <- linenoise str + maybePeek BSU.unsafePackCString ptr + errno <- getErrno + if errno == eAGAIN + then resetErrno >> pure InterruptResult + else pure (maybe EofResult LineResult res) + +-- | Add to current history. +addHistory :: ByteString -> IO () +addHistory = + flip BSU.unsafeUseAsCString $ \str -> do + _ <- linenoiseHistoryAdd str + pure () + +-- | Limit the maximum history length. +stifleHistory :: Int -> IO () +stifleHistory len = do + _ <- linenoiseHistorySetMaxLen $ fromIntegral len + pure () + +-- | Save history to a file. +historySave :: FilePath -> IO () +historySave fname = do + str <- newCString fname + linenoiseHistorySave str + +-- | Load history from a file. +historyLoad :: FilePath -> IO () +historyLoad fname = do + str <- newCString fname + linenoiseHistoryLoad str + +-- | Clear the screen. +clearScreen :: IO () +clearScreen = linenoiseClearScreen + +-- | Enable/Disable multiline input. +setMultiline :: Bool -> IO () +setMultiline = linenoiseSetMultiLine . fromBool + +-- | Print keycodes. +printKeycodes :: IO () +printKeycodes = linenoisePrintKeyCodes + +-- | Set the current completion function. +setCompletion :: (ByteString -> IO [ByteString]) -> IO () +setCompletion f = do + cb <- makeFunPtr (makeCompletion f) + linenoiseSetCompletionCallback cb diff --git a/src/Linenoise/Repl.hs b/src/Linenoise/Repl.hs new file mode 100644 --- /dev/null +++ b/src/Linenoise/Repl.hs @@ -0,0 +1,93 @@ +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE GeneralizedNewtypeDeriving #-} +{-# LANGUAGE MultiParamTypeClasses #-} + +-- | Helper functions and transformer to write your own REPLs. +module Linenoise.Repl + ( ReplDirective (..) + , ReplT (..) + , replM + , runReplT + ) where + +import Control.Applicative (Alternative) +import Control.Monad (MonadPlus) +import Control.Monad.Catch (MonadCatch, MonadThrow) +import Control.Monad.Fail (MonadFail) +import Control.Monad.Fix (MonadFix) +import Control.Monad.IO.Class (MonadIO (..)) +import Control.Monad.IO.Unlift (MonadUnliftIO (..), UnliftIO (..)) +import Control.Monad.Reader (MonadReader, ReaderT (..), ask) +import Control.Monad.State.Strict (MonadState (..)) +import Control.Monad.Trans (MonadTrans (..)) +import Control.Monad.Zip (MonadZip) +import Data.Text (Text) +import Data.IORef (IORef, newIORef, readIORef, writeIORef) +import Linenoise.Unlift (InputResult (..)) +import qualified Linenoise.Unlift as Unlift + +-- | Basic monad transformer with mutable state that can be used with all "Linenoise.Unlift" functions. +-- You do not have to use this, but it's here to cover most of what you would need without having +-- to roll your own newtype. +newtype ReplT r s m a = ReplT { unReplT :: ReaderT r (ReaderT (IORef s) m) a } + deriving (Functor, Applicative, Monad, MonadIO, + Alternative, MonadPlus, MonadFix, MonadZip, + MonadFail, MonadThrow, MonadCatch, + MonadReader r) + +askRef :: Applicative m => ReplT r s m (IORef s) +askRef = ReplT (ReaderT (const (ReaderT pure))) + +refReplT :: ReplT r s m a -> r -> IORef s -> m a +refReplT n r = runReaderT (runReaderT (unReplT n) r) + +instance MonadTrans (ReplT r s) where + lift = ReplT . lift . lift + +instance MonadUnliftIO m => MonadUnliftIO (ReplT r s m) where + askUnliftIO = do + UnliftIO run <- lift askUnliftIO + r <- ask + ref <- askRef + pure (UnliftIO (\n -> run (refReplT n r ref))) + +instance MonadIO m => MonadState s (ReplT r s m) where + get = ReplT (ReaderT (const (ReaderT (liftIO . readIORef)))) + put s = ReplT (ReaderT (const (ReaderT (\ref -> liftIO (writeIORef ref s))))) + +-- | Run a ReplT. +runReplT :: MonadIO m => ReplT r s m a -> r -> s -> m (a, s) +runReplT n r s = do + ref <- liftIO (newIORef s) + res <- refReplT n r ref + final <- liftIO (readIORef ref) + pure (res, final) + +-- | Directive to control voluntary REPL termination. +data ReplDirective + = ReplQuit + | ReplContinue + deriving (Eq, Show) + +-- | Run a simple REPL. +replM + :: MonadUnliftIO m + => ReplDirective -- ^ Directive on interrupt + -> Text -- ^ Prompt + -> (Text -> m ReplDirective) -- ^ Action + -> (Text -> m [Text]) -- ^ Completion + -> m () +replM onInterrupt prompt action comp = loop where + loop = do + Unlift.setCompletion comp + res <- Unlift.getInputLine prompt + directive <- case res of + InterruptResult -> pure onInterrupt + EofResult -> pure ReplQuit + LineResult line -> do + directive <- action line + Unlift.addHistory line + pure directive + case directive of + ReplContinue -> loop + ReplQuit -> pure () diff --git a/src/Linenoise/Unlift.hs b/src/Linenoise/Unlift.hs new file mode 100644 --- /dev/null +++ b/src/Linenoise/Unlift.hs @@ -0,0 +1,58 @@ +-- | Unlifted versions of all FFI methods. +module Linenoise.Unlift + ( InputResult (..) + , addHistory + , clearScreen + , getInputLine + , historyLoad + , historySave + , printKeycodes + , setCompletion + , setMultiline + , stifleHistory + ) where + +import Control.Monad.IO.Class (MonadIO, liftIO) +import Control.Monad.IO.Unlift (MonadUnliftIO, withRunInIO) +import Data.Text (Text) +import Data.Text.Encoding (decodeUtf8, encodeUtf8) +import Linenoise.FFI (InputResult (..)) +import qualified Linenoise.FFI as FFI + +-- | Add to current history. +addHistory :: MonadIO m => Text -> m () +addHistory = liftIO . FFI.addHistory . encodeUtf8 + +-- | Clear the screen. +clearScreen :: MonadIO m => m () +clearScreen = liftIO FFI.clearScreen + +-- | Run the prompt, yielding a string. +getInputLine :: MonadIO m => Text -> m (InputResult Text) +getInputLine = liftIO . fmap (fmap decodeUtf8) . FFI.getInputLine . encodeUtf8 + +-- | Load history from a file. +historyLoad :: MonadIO m => FilePath -> m () +historyLoad = liftIO . FFI.historyLoad + +-- | Save history to a file. +historySave :: MonadIO m => FilePath -> m () +historySave = liftIO . FFI.historySave + +-- | Print keycodes. +printKeycodes :: MonadIO m => m () +printKeycodes = liftIO FFI.printKeycodes + +-- | Set the current completion function. +setCompletion :: MonadUnliftIO m => (Text -> m [Text]) -> m () +setCompletion f = + let g = fmap (fmap encodeUtf8) . f . decodeUtf8 + in withRunInIO (\runInIO -> FFI.setCompletion (runInIO . g)) + +-- | Enable/Disable multiline input. +setMultiline :: MonadIO m => Bool -> m () +setMultiline = liftIO . FFI.setMultiline + +-- | Limit the maximum history length. +stifleHistory :: MonadIO m => Int -> m () +stifleHistory = liftIO . FFI.stifleHistory