Edit
kc3-lang/linenoise/linenoise.c
antirez
- 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, Salvatore Sanfilippo <antirez 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. * * Neither the name of Redis nor the names of its contributors may be used * to endorse or promote products derived from this software without * specific prior written permission. * * 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 OWNER 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: * - Switch to gets() if $TERM is something we can't support. * - Filter bogus Ctrl+<char> combinations. * - Win32 support * * Bloat: * - Completion? * - 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. * * CHA (Cursor Horizontal Absolute) * Sequence: ESC [ n G * Effect: moves cursor to column n * * 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 of n chars * */ #include <termios.h> #include <unistd.h> #include <stdlib.h> #include <stdio.h> #include <errno.h> #include <string.h> #include <stdlib.h> #include <sys/types.h> #include <sys/ioctl.h> #include <unistd.h> #define LINENOISE_DEFAULT_HISTORY_MAX_LEN 100 #define LINENOISE_MAX_LINE 4096 static char *unsupported_term[] = {"dumb","cons25",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 atexit_registered = 0; /* register atexit just 1 time */ static int history_max_len = LINENOISE_DEFAULT_HISTORY_MAX_LEN; static int history_len = 0; char **history = NULL; static void linenoiseAtExit(void); int linenoiseHistoryAdd(const char *line); 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; } static void freeHistory(void) { if (history) { int j; for (j = 0; j < history_len; j++) free(history[j]); free(history); } } 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; } /* At exit we'll try to fix the terminal to the initial conditions. */ static void linenoiseAtExit(void) { disableRawMode(STDIN_FILENO); freeHistory(); } static int getColumns(void) { struct winsize ws; if (ioctl(1, TIOCGWINSZ, &ws) == -1) return 80; return ws.ws_col; } static void refreshLine(int fd, const char *prompt, char *buf, size_t len, size_t pos, size_t cols) { char seq[64]; size_t plen = strlen(prompt); while((plen+pos) >= cols) { buf++; len--; pos--; } while (plen+len > cols) { len--; } /* Cursor to left edge */ snprintf(seq,64,"\x1b[0G"); if (write(fd,seq,strlen(seq)) == -1) return; /* Write the prompt and the current buffer content */ if (write(fd,prompt,strlen(prompt)) == -1) return; if (write(fd,buf,len) == -1) return; /* Erase to right */ snprintf(seq,64,"\x1b[0K"); if (write(fd,seq,strlen(seq)) == -1) return; /* Move cursor to original position. */ snprintf(seq,64,"\x1b[0G\x1b[%dC", (int)(pos+plen)); if (write(fd,seq,strlen(seq)) == -1) return; } static int linenoisePrompt(int fd, char *buf, size_t buflen, const char *prompt) { size_t plen = strlen(prompt); size_t pos = 0; size_t len = 0; size_t cols = getColumns(); int history_index = 0; buf[0] = '\0'; 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(fd,prompt,plen) == -1) return -1; while(1) { char c; int nread; char seq[2]; nread = read(fd,&c,1); if (nread <= 0) return len; switch(c) { case 13: /* enter */ history_len--; return len; case 4: /* ctrl-d */ history_len--; return (len == 0) ? -1 : (int)len; case 3: /* ctrl-c */ errno = EAGAIN; return -1; case 127: /* backspace */ case 8: /* ctrl-h */ if (pos > 0 && len > 0) { memmove(buf+pos-1,buf+pos,len-pos); pos--; len--; buf[len] = '\0'; refreshLine(fd,prompt,buf,len,pos,cols); } break; case 20: /* ctrl-t */ if (pos > 0 && pos < len) { int aux = buf[pos-1]; buf[pos-1] = buf[pos]; buf[pos] = aux; if (pos != len-1) pos++; refreshLine(fd,prompt,buf,len,pos,cols); } break; case 2: /* ctrl-b */ goto left_arrow; case 6: /* ctrl-f */ goto right_arrow; case 16: /* ctrl-p */ seq[1] = 65; goto up_down_arrow; case 14: /* ctrl-n */ seq[1] = 66; goto up_down_arrow; break; case 27: /* escape sequence */ if (read(fd,seq,2) == -1) break; if (seq[0] == 91 && seq[1] == 68) { left_arrow: /* left arrow */ if (pos > 0) { pos--; refreshLine(fd,prompt,buf,len,pos,cols); } } else if (seq[0] == 91 && seq[1] == 67) { right_arrow: /* right arrow */ if (pos != len) { pos++; refreshLine(fd,prompt,buf,len,pos,cols); } } else if (seq[0] == 91 && (seq[1] == 65 || seq[1] == 66)) { up_down_arrow: /* up and down arrow: history */ if (history_len > 1) { /* Update the current history entry before to * overwrite it with tne next one. */ free(history[history_len-1-history_index]); history[history_len-1-history_index] = strdup(buf); /* Show the new entry */ history_index += (seq[1] == 65) ? 1 : -1; if (history_index < 0) { history_index = 0; break; } else if (history_index >= history_len) { history_index = history_len-1; break; } strncpy(buf,history[history_len-1-history_index],buflen); buf[buflen] = '\0'; len = pos = strlen(buf); refreshLine(fd,prompt,buf,len,pos,cols); } } break; default: if (len < buflen) { if (len == pos) { buf[pos] = c; pos++; len++; buf[len] = '\0'; if (plen+len < cols) { /* Avoid a full update of the line in the * trivial case. */ if (write(fd,&c,1) == -1) return -1; } else { refreshLine(fd,prompt,buf,len,pos,cols); } } else { memmove(buf+pos+1,buf+pos,len-pos); buf[pos] = c; len++; pos++; buf[len] = '\0'; refreshLine(fd,prompt,buf,len,pos,cols); } } break; case 21: /* Ctrl+u, delete the whole line. */ buf[0] = '\0'; pos = len = 0; refreshLine(fd,prompt,buf,len,pos,cols); break; case 11: /* Ctrl+k, delete from current to end of line. */ buf[pos] = '\0'; len = pos; refreshLine(fd,prompt,buf,len,pos,cols); break; case 1: /* Ctrl+a, go to the start of the line */ pos = 0; refreshLine(fd,prompt,buf,len,pos,cols); break; case 5: /* ctrl+e, go to the end of the line */ pos = len; refreshLine(fd,prompt,buf,len,pos,cols); break; } } return len; } static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) { int fd = STDIN_FILENO; int count; if (buflen == 0) { errno = EINVAL; return -1; } if (!isatty(STDIN_FILENO)) { if (fgets(buf, buflen, stdin) == NULL) return -1; count = strlen(buf); if (count && buf[count-1] == '\n') { count--; buf[count] = '\0'; } } else { if (enableRawMode(fd) == -1) return -1; count = linenoisePrompt(fd, buf, buflen, prompt); disableRawMode(fd); printf("\n"); } return count; } char *linenoise(const char *prompt) { char buf[LINENOISE_MAX_LINE]; int count; 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); } } /* 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; if (history == NULL) { history = malloc(sizeof(char*)*history_max_len); if (history == NULL) return 0; memset(history,0,(sizeof(char*)*history_max_len)); } 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; } 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 (len < tocopy) tocopy = len; memcpy(new,history+(history_max_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; }