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Diffstat (limited to 'usr.bin/more/decode.c')
| -rw-r--r-- | usr.bin/more/decode.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/usr.bin/more/decode.c b/usr.bin/more/decode.c new file mode 100644 index 0000000..83fa624 --- /dev/null +++ b/usr.bin/more/decode.c @@ -0,0 +1,201 @@ +/* + * Copyright (c) 1988 Mark Nudleman + * Copyright (c) 1988, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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. + */ + +#ifndef lint +static char sccsid[] = "@(#)decode.c 8.1 (Berkeley) 6/6/93"; +#endif /* not lint */ + +/* + * Routines to decode user commands. + * + * This is all table driven. + * A command table is a sequence of command descriptors. + * Each command descriptor is a sequence of bytes with the following format: + * <c1><c2>...<cN><0><action> + * The characters c1,c2,...,cN are the command string; that is, + * the characters which the user must type. + * It is terminated by a null <0> byte. + * The byte after the null byte is the action code associated + * with the command string. + * + * The default commands are described by cmdtable. + */ + +#include <sys/param.h> +#include <sys/file.h> +#include <stdio.h> +#include <less.h> + +/* + * Command table is ordered roughly according to expected + * frequency of use, so the common commands are near the beginning. + */ +#define CONTROL(c) ((c)&037) + +static char cmdtable[] = { + '\r',0, A_F_LINE, + '\n',0, A_F_LINE, + 'j',0, A_F_LINE, + 'k',0, A_B_LINE, + 'd',0, A_F_SCROLL, + CONTROL('D'),0, A_F_SCROLL, + 'u',0, A_B_SCROLL, + CONTROL('U'),0, A_B_SCROLL, + ' ',0, A_F_SCREEN, + 'f',0, A_F_SCREEN, + CONTROL('F'),0, A_F_SCREEN, + 'b',0, A_B_SCREEN, + CONTROL('B'),0, A_B_SCREEN, + 'R',0, A_FREPAINT, + 'r',0, A_REPAINT, + CONTROL('L'),0, A_REPAINT, + 'g',0, A_GOLINE, + 'p',0, A_PERCENT, + '%',0, A_PERCENT, + 'G',0, A_GOEND, + '0',0, A_DIGIT, + '1',0, A_DIGIT, + '2',0, A_DIGIT, + '3',0, A_DIGIT, + '4',0, A_DIGIT, + '5',0, A_DIGIT, + '6',0, A_DIGIT, + '7',0, A_DIGIT, + '8',0, A_DIGIT, + '9',0, A_DIGIT, + + '=',0, A_STAT, + CONTROL('G'),0, A_STAT, + '/',0, A_F_SEARCH, + '?',0, A_B_SEARCH, + 'n',0, A_AGAIN_SEARCH, + 'm',0, A_SETMARK, + '\'',0, A_GOMARK, + 'E',0, A_EXAMINE, + 'N',0, A_NEXT_FILE, + ':','n',0, A_NEXT_FILE, + 'P',0, A_PREV_FILE, + ':','p',0, A_PREV_FILE, + 'v',0, A_VISUAL, + + 'h',0, A_HELP, + 'q',0, A_QUIT, + ':','q',0, A_QUIT, + ':','t',0, A_TAGFILE, + ':', 'a', 0, A_FILE_LIST, + 'Z','Z',0, A_QUIT, +}; + +char *cmdendtable = cmdtable + sizeof(cmdtable); + +#define MAX_CMDLEN 16 + +static char kbuf[MAX_CMDLEN+1]; +static char *kp = kbuf; + +/* + * Indicate that we're not in a prefix command + * by resetting the command buffer pointer. + */ +noprefix() +{ + kp = kbuf; +} + +/* + * Decode a command character and return the associated action. + */ +cmd_decode(c) + int c; +{ + register int action = A_INVALID; + + /* + * Append the new command character to the command string in kbuf. + */ + *kp++ = c; + *kp = '\0'; + + action = cmd_search(cmdtable, cmdendtable); + + /* This is not a prefix character. */ + if (action != A_PREFIX) + noprefix(); + return(action); +} + +/* + * Search a command table for the current command string (in kbuf). + */ +cmd_search(table, endtable) + char *table; + char *endtable; +{ + register char *p, *q; + + for (p = table, q = kbuf; p < endtable; p++, q++) { + if (*p == *q) { + /* + * Current characters match. + * If we're at the end of the string, we've found it. + * Return the action code, which is the character + * after the null at the end of the string + * in the command table. + */ + if (*p == '\0') + return(p[1]); + } + else if (*q == '\0') { + /* + * Hit the end of the user's command, + * but not the end of the string in the command table. + * The user's command is incomplete. + */ + return(A_PREFIX); + } else { + /* + * Not a match. + * Skip ahead to the next command in the + * command table, and reset the pointer + * to the user's command. + */ + while (*p++ != '\0'); + q = kbuf-1; + } + } + /* + * No match found in the entire command table. + */ + return(A_INVALID); +} |
