freebsd-dev/contrib/nvi/vi/v_word.c
2015-04-10 17:50:28 +00:00

527 lines
13 KiB
C

/*-
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1992, 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*
* See the LICENSE file for redistribution information.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "$Id: v_word.c,v 10.7 2011/12/27 00:49:31 zy Exp $";
#endif /* not lint */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <bitstring.h>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include "../common/common.h"
#include "vi.h"
/*
* There are two types of "words". Bigwords are easy -- groups of anything
* delimited by whitespace. Normal words are trickier. They are either a
* group of characters, numbers and underscores, or a group of anything but,
* delimited by whitespace. When for a word, if you're in whitespace, it's
* easy, just remove the whitespace and go to the beginning or end of the
* word. Otherwise, figure out if the next character is in a different group.
* If it is, go to the beginning or end of that group, otherwise, go to the
* beginning or end of the current group. The historic version of vi didn't
* get this right, so, for example, there were cases where "4e" was not the
* same as "eeee" -- in particular, single character words, and commands that
* began in whitespace were almost always handled incorrectly. To get it right
* you have to resolve the cursor after each search so that the look-ahead to
* figure out what type of "word" the cursor is in will be correct.
*
* Empty lines, and lines that consist of only white-space characters count
* as a single word, and the beginning and end of the file counts as an
* infinite number of words.
*
* Movements associated with commands are different than movement commands.
* For example, in "abc def", with the cursor on the 'a', "cw" is from
* 'a' to 'c', while "w" is from 'a' to 'd'. In general, trailing white
* space is discarded from the change movement. Another example is that,
* in the same string, a "cw" on any white space character replaces that
* single character, and nothing else. Ain't nothin' in here that's easy.
*
* One historic note -- in the original vi, the 'w', 'W' and 'B' commands
* would treat groups of empty lines as individual words, i.e. the command
* would move the cursor to each new empty line. The 'e' and 'E' commands
* would treat groups of empty lines as a single word, i.e. the first use
* would move past the group of lines. The 'b' command would just beep at
* you, or, if you did it from the start of the line as part of a motion
* command, go absolutely nuts. If the lines contained only white-space
* characters, the 'w' and 'W' commands would just beep at you, and the 'B',
* 'b', 'E' and 'e' commands would treat the group as a single word, and
* the 'B' and 'b' commands will treat the lines as individual words. This
* implementation treats all of these cases as a single white-space word.
*/
enum which {BIGWORD, LITTLEWORD};
static int bword(SCR *, VICMD *, enum which);
static int eword(SCR *, VICMD *, enum which);
static int fword(SCR *, VICMD *, enum which);
/*
* v_wordW -- [count]W
* Move forward a bigword at a time.
*
* PUBLIC: int v_wordW(SCR *, VICMD *);
*/
int
v_wordW(SCR *sp, VICMD *vp)
{
return (fword(sp, vp, BIGWORD));
}
/*
* v_wordw -- [count]w
* Move forward a word at a time.
*
* PUBLIC: int v_wordw(SCR *, VICMD *);
*/
int
v_wordw(SCR *sp, VICMD *vp)
{
return (fword(sp, vp, LITTLEWORD));
}
/*
* fword --
* Move forward by words.
*/
static int
fword(SCR *sp, VICMD *vp, enum which type)
{
enum { INWORD, NOTWORD } state;
VCS cs;
u_long cnt;
cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
cs.cs_lno = vp->m_start.lno;
cs.cs_cno = vp->m_start.cno;
if (cs_init(sp, &cs))
return (1);
/*
* If in white-space:
* If the count is 1, and it's a change command, we're done.
* Else, move to the first non-white-space character, which
* counts as a single word move. If it's a motion command,
* don't move off the end of the line.
*/
if (cs.cs_flags == CS_EMP || (cs.cs_flags == 0 && ISBLANK(cs.cs_ch))) {
if (ISMOTION(vp) && cs.cs_flags != CS_EMP && cnt == 1) {
if (ISCMD(vp->rkp, 'c'))
return (0);
if (ISCMD(vp->rkp, 'd') || ISCMD(vp->rkp, 'y')) {
if (cs_fspace(sp, &cs))
return (1);
goto ret;
}
}
if (cs_fblank(sp, &cs))
return (1);
--cnt;
}
/*
* Cyclically move to the next word -- this involves skipping
* over word characters and then any trailing non-word characters.
* Note, for the 'w' command, the definition of a word keeps
* switching.
*/
if (type == BIGWORD)
while (cnt--) {
for (;;) {
if (cs_next(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
break;
}
/*
* If a motion command and we're at the end of the
* last word, we're done. Delete and yank eat any
* trailing blanks, but we don't move off the end
* of the line regardless.
*/
if (cnt == 0 && ISMOTION(vp)) {
if ((ISCMD(vp->rkp, 'd') ||
ISCMD(vp->rkp, 'y')) &&
cs_fspace(sp, &cs))
return (1);
break;
}
/* Eat whitespace characters. */
if (cs_fblank(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
}
else
while (cnt--) {
state = cs.cs_flags == 0 &&
inword(cs.cs_ch) ? INWORD : NOTWORD;
for (;;) {
if (cs_next(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
break;
if (state == INWORD) {
if (!inword(cs.cs_ch))
break;
} else
if (inword(cs.cs_ch))
break;
}
/* See comment above. */
if (cnt == 0 && ISMOTION(vp)) {
if ((ISCMD(vp->rkp, 'd') ||
ISCMD(vp->rkp, 'y')) &&
cs_fspace(sp, &cs))
return (1);
break;
}
/* Eat whitespace characters. */
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
if (cs_fblank(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
}
/*
* If we didn't move, we must be at EOF.
*
* !!!
* That's okay for motion commands, however.
*/
ret: if (!ISMOTION(vp) &&
cs.cs_lno == vp->m_start.lno && cs.cs_cno == vp->m_start.cno) {
v_eof(sp, &vp->m_start);
return (1);
}
/* Adjust the end of the range for motion commands. */
vp->m_stop.lno = cs.cs_lno;
vp->m_stop.cno = cs.cs_cno;
if (ISMOTION(vp) && cs.cs_flags == 0)
--vp->m_stop.cno;
/*
* Non-motion commands move to the end of the range. Delete
* and yank stay at the start, ignore others.
*/
vp->m_final = ISMOTION(vp) ? vp->m_start : vp->m_stop;
return (0);
}
/*
* v_wordE -- [count]E
* Move forward to the end of the bigword.
*
* PUBLIC: int v_wordE(SCR *, VICMD *);
*/
int
v_wordE(SCR *sp, VICMD *vp)
{
return (eword(sp, vp, BIGWORD));
}
/*
* v_worde -- [count]e
* Move forward to the end of the word.
*
* PUBLIC: int v_worde(SCR *, VICMD *);
*/
int
v_worde(SCR *sp, VICMD *vp)
{
return (eword(sp, vp, LITTLEWORD));
}
/*
* eword --
* Move forward to the end of the word.
*/
static int
eword(SCR *sp, VICMD *vp, enum which type)
{
enum { INWORD, NOTWORD } state;
VCS cs;
u_long cnt;
cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
cs.cs_lno = vp->m_start.lno;
cs.cs_cno = vp->m_start.cno;
if (cs_init(sp, &cs))
return (1);
/*
* !!!
* If in whitespace, or the next character is whitespace, move past
* it. (This doesn't count as a word move.) Stay at the character
* past the current one, it sets word "state" for the 'e' command.
*/
if (cs.cs_flags == 0 && !ISBLANK(cs.cs_ch)) {
if (cs_next(sp, &cs))
return (1);
if (cs.cs_flags == 0 && !ISBLANK(cs.cs_ch))
goto start;
}
if (cs_fblank(sp, &cs))
return (1);
/*
* Cyclically move to the next word -- this involves skipping
* over word characters and then any trailing non-word characters.
* Note, for the 'e' command, the definition of a word keeps
* switching.
*/
start: if (type == BIGWORD)
while (cnt--) {
for (;;) {
if (cs_next(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
break;
}
/*
* When we reach the start of the word after the last
* word, we're done. If we changed state, back up one
* to the end of the previous word.
*/
if (cnt == 0) {
if (cs.cs_flags == 0 && cs_prev(sp, &cs))
return (1);
break;
}
/* Eat whitespace characters. */
if (cs_fblank(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
}
else
while (cnt--) {
state = cs.cs_flags == 0 &&
inword(cs.cs_ch) ? INWORD : NOTWORD;
for (;;) {
if (cs_next(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
break;
if (state == INWORD) {
if (!inword(cs.cs_ch))
break;
} else
if (inword(cs.cs_ch))
break;
}
/* See comment above. */
if (cnt == 0) {
if (cs.cs_flags == 0 && cs_prev(sp, &cs))
return (1);
break;
}
/* Eat whitespace characters. */
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
if (cs_fblank(sp, &cs))
return (1);
if (cs.cs_flags == CS_EOF)
goto ret;
}
/*
* If we didn't move, we must be at EOF.
*
* !!!
* That's okay for motion commands, however.
*/
ret: if (!ISMOTION(vp) &&
cs.cs_lno == vp->m_start.lno && cs.cs_cno == vp->m_start.cno) {
v_eof(sp, &vp->m_start);
return (1);
}
/* Set the end of the range for motion commands. */
vp->m_stop.lno = cs.cs_lno;
vp->m_stop.cno = cs.cs_cno;
/*
* Non-motion commands move to the end of the range.
* Delete and yank stay at the start, ignore others.
*/
vp->m_final = ISMOTION(vp) ? vp->m_start : vp->m_stop;
return (0);
}
/*
* v_WordB -- [count]B
* Move backward a bigword at a time.
*
* PUBLIC: int v_wordB(SCR *, VICMD *);
*/
int
v_wordB(SCR *sp, VICMD *vp)
{
return (bword(sp, vp, BIGWORD));
}
/*
* v_wordb -- [count]b
* Move backward a word at a time.
*
* PUBLIC: int v_wordb(SCR *, VICMD *);
*/
int
v_wordb(SCR *sp, VICMD *vp)
{
return (bword(sp, vp, LITTLEWORD));
}
/*
* bword --
* Move backward by words.
*/
static int
bword(SCR *sp, VICMD *vp, enum which type)
{
enum { INWORD, NOTWORD } state;
VCS cs;
u_long cnt;
cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
cs.cs_lno = vp->m_start.lno;
cs.cs_cno = vp->m_start.cno;
if (cs_init(sp, &cs))
return (1);
/*
* !!!
* If in whitespace, or the previous character is whitespace, move
* past it. (This doesn't count as a word move.) Stay at the
* character before the current one, it sets word "state" for the
* 'b' command.
*/
if (cs.cs_flags == 0 && !ISBLANK(cs.cs_ch)) {
if (cs_prev(sp, &cs))
return (1);
if (cs.cs_flags == 0 && !ISBLANK(cs.cs_ch))
goto start;
}
if (cs_bblank(sp, &cs))
return (1);
/*
* Cyclically move to the beginning of the previous word -- this
* involves skipping over word characters and then any trailing
* non-word characters. Note, for the 'b' command, the definition
* of a word keeps switching.
*/
start: if (type == BIGWORD)
while (cnt--) {
for (;;) {
if (cs_prev(sp, &cs))
return (1);
if (cs.cs_flags == CS_SOF)
goto ret;
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
break;
}
/*
* When we reach the end of the word before the last
* word, we're done. If we changed state, move forward
* one to the end of the next word.
*/
if (cnt == 0) {
if (cs.cs_flags == 0 && cs_next(sp, &cs))
return (1);
break;
}
/* Eat whitespace characters. */
if (cs_bblank(sp, &cs))
return (1);
if (cs.cs_flags == CS_SOF)
goto ret;
}
else
while (cnt--) {
state = cs.cs_flags == 0 &&
inword(cs.cs_ch) ? INWORD : NOTWORD;
for (;;) {
if (cs_prev(sp, &cs))
return (1);
if (cs.cs_flags == CS_SOF)
goto ret;
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
break;
if (state == INWORD) {
if (!inword(cs.cs_ch))
break;
} else
if (inword(cs.cs_ch))
break;
}
/* See comment above. */
if (cnt == 0) {
if (cs.cs_flags == 0 && cs_next(sp, &cs))
return (1);
break;
}
/* Eat whitespace characters. */
if (cs.cs_flags != 0 || ISBLANK(cs.cs_ch))
if (cs_bblank(sp, &cs))
return (1);
if (cs.cs_flags == CS_SOF)
goto ret;
}
/* If we didn't move, we must be at SOF. */
ret: if (cs.cs_lno == vp->m_start.lno && cs.cs_cno == vp->m_start.cno) {
v_sof(sp, &vp->m_start);
return (1);
}
/* Set the end of the range for motion commands. */
vp->m_stop.lno = cs.cs_lno;
vp->m_stop.cno = cs.cs_cno;
/*
* All commands move to the end of the range. Motion commands
* adjust the starting point to the character before the current
* one.
*
* !!!
* The historic vi didn't get this right -- the `yb' command yanked
* the right stuff and even updated the cursor value, but the cursor
* was not actually updated on the screen.
*/
vp->m_final = vp->m_stop;
if (ISMOTION(vp))
--vp->m_start.cno;
return (0);
}