-
Notifications
You must be signed in to change notification settings - Fork 4
/
basic.c
345 lines (317 loc) · 7.75 KB
/
basic.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
/*
The routines in this file move the cursor around on the screen. They
compute a new value for the cursor, then adjust dot. The display code
always updates the cursor location, so only moves between lines, or
functions that adjust the top line in the window and invalidate the
framing, are hard.
*/
#include "ue.h"
static int curgoal; /* Goal column */
/* Move the cursor to the beginning of the current line.
*/
int gotobol(int f, int n)
{
UNUSED(f);
UNUSED(n);
curwp->w_doto = 0;
return TRUE;
}
/*
Move the cursor backwards by "n" characters. If "n" is less than zero call
"forwchar" to actually do the move. Otherwise compute the new cursor
location. Error if you try and move out of the buffer. Set the flag if the
line pointer for dot changes.
*/
int backchar(int f, int n)
{
ELINE *lp;
if (n < 0)
return forwchar(f, -n);
while (n--)
{
if (curwp->w_doto == 0)
{
if ((lp = lback(curwp->w_dotp)) == curbp->b_linep)
return FALSE;
curwp->w_dotp = lp;
curwp->w_doto = llength(lp);
curwp->w_flag |= WFMOVE;
} else
curwp->w_doto--;
}
return TRUE;
}
/*
Move the cursor to the end of the current line. Trivial. No errors.
*/
int gotoeol(int f, int n)
{
UNUSED(f);
UNUSED(n);
curwp->w_doto = llength(curwp->w_dotp);
return TRUE;
}
/*
Move the cursor forwwards by "n" characters. If "n" is less than zero call
"backchar" to actually do the move. Otherwise compute the new cursor
location, and move ".". Error if you try and move off the end of the
buffer. Set the flag if the line pointer for dot changes.
*/
int forwchar(int f, int n)
{
ELINE *lp;
if (n < 0)
return backchar(f, -n);
while (n--)
{
lp = curwp->w_dotp;
if (curwp->w_doto == llength(lp))
{
if (lp == curbp->b_linep)
return FALSE;
curwp->w_dotp = lforw(lp);
curwp->w_doto = 0;
curwp->w_flag |= WFMOVE;
} else
{
curwp->w_doto++;
}
}
return TRUE;
}
/*
Goto the beginning of the buffer. Massive adjustment of dot. This is
considered to be hard motion; it really isn't if the original value of dot
is the same as the new value of dot. Normally bound to "M-<".
*/
int gotobob(int f, int n)
{
setmark(f, n);
curwp->w_dotp = lforw(curbp->b_linep);
curwp->w_doto = 0;
curwp->w_flag |= WFHARD;
return TRUE;
}
/*
Move to the end of the buffer. Dot is always put at the end of the file
(ZJ). The standard screen code does most of the hard parts of update.
Bound to "M->".
*/
int igotoeob(void)
{
curwp->w_dotp = curbp->b_linep;
curwp->w_doto = 0;
curwp->w_flag |= WFHARD;
return TRUE;
}
int gotoeob(int f, int n)
{
setmark(f, n);
return igotoeob();
}
/*
This routine, given a pointer to a ELINE, and the current cursor goal
column, return the best choice for the offset. The offset is returned.
Used by "C-N" and "C-P".
*/
static int getgoal(ELINE *dlp)
{
int c;
int col;
int newcol;
int dbo;
col = 0;
dbo = 0;
while (dbo != llength(dlp))
{
c = lgetc(dlp, dbo);
newcol = col;
if (c == '\t')
newcol |= 0x07;
else if (c < 0x20 || c == 0x7F)
++newcol;
++newcol;
if (newcol > curgoal)
break;
col = newcol;
++dbo;
}
return dbo;
}
/*
Move forward by full lines. If the number of lines to move is less than
zero, call the backward line function to actually do it. The last command
controls how the goal column is set. Bound to "C-N". No errors are
possible.
*/
int forwline(int f, int n)
{
ELINE *dlp;
if (n < 0)
return backline(f, -n);
if ((lastflag & CFCPCN) == 0) /* Reset goal if last */
curgoal = curcol; /* not C-P or C-N */
thisflag |= CFCPCN;
dlp = curwp->w_dotp;
while (n-- && dlp != curbp->b_linep)
dlp = lforw(dlp);
curwp->w_dotp = dlp;
curwp->w_doto = getgoal(dlp);
curwp->w_flag |= WFMOVE;
return TRUE;
}
/*
This function is like "forwline", but goes backwards. The scheme is exactly
the same. Check for arguments that are less than zero and call your
alternate. Figure out the new line and call "movedot" to perform the
motion. No errors are possible. Bound to "C-P".
*/
int backline(int f, int n)
{
ELINE *dlp;
if (n < 0)
return forwline(f, -n);
if ((lastflag & CFCPCN) == 0)
curgoal = curcol;
thisflag |= CFCPCN;
dlp = curwp->w_dotp;
while (n-- && lback(dlp) != curbp->b_linep)
dlp = lback(dlp);
curwp->w_dotp = dlp;
curwp->w_doto = getgoal(dlp);
curwp->w_flag |= WFMOVE;
return TRUE;
}
/*
Scroll forward by a specified number of lines, or by a full page if no
argument. Bound to "C-V". The "2" in the arithmetic on the window size is
the overlap; this value is the default overlap value in ITS EMACS. Because
this zaps the top line in the display window, we have to do a hard update.
*/
int forwpage(int f, int n)
{
ELINE *lp;
if (f == FALSE)
{
n = curwp->w_ntrows - 2; /* Default scroll. */
if (n <= 0) /* Forget the overlap */
n = 1; /* if tiny window. */
} else if (n < 0)
{
return backpage(f, -n);
} else /* Convert from pages */
{
n *= curwp->w_ntrows; /* to lines. */
}
lp = curwp->w_linep;
while (n-- && lp != curbp->b_linep)
lp = lforw(lp);
curwp->w_linep = lp;
curwp->w_dotp = lp;
curwp->w_doto = 0;
curwp->w_flag |= WFHARD;
return TRUE;
}
/*
This command is like "forwpage", but it goes backwards. The "2", like
above, is the overlap between the two windows. The value is from the ITS
EMACS manual. Bound to "M-V". We do a hard update for exactly the same
reason.
*/
int backpage(int f, int n)
{
ELINE *lp;
if (f == FALSE)
{
n = curwp->w_ntrows - 2; /* Default scroll. */
if (n <= 0) /* Don't blow up if the */
n = 1; /* window is tiny. */
} else if (n < 0)
{
return forwpage(f, -n);
} else /* Convert from pages */
{
n *= curwp->w_ntrows; /* to lines. */
}
lp = curwp->w_linep;
while (n-- && lback(lp) != curbp->b_linep)
lp = lback(lp);
curwp->w_linep = lp;
curwp->w_dotp = lp;
curwp->w_doto = 0;
curwp->w_flag |= WFHARD;
return TRUE;
}
void isetmark(void)
{
curwp->w_markp = curwp->w_dotp;
curwp->w_marko = curwp->w_doto;
}
/*
Set the mark in the current window to the value of "." in the window. No
errors are possible. Bound to "M-.".
*/
int setmark(int f, int n)
{
UNUSED(f);
UNUSED(n);
isetmark();
mlwrite("[Mark set]");
return TRUE;
}
/*
Swap the values of "." and "mark" in the current window. This is pretty
easy, bacause all of the hard work gets done by the standard routine
that moves the mark about. The only possible error is "no mark". Bound to
"C-X C-X".
*/
int swapmark(int f, int n)
{
ELINE *odotp;
int odoto;
UNUSED(f);
UNUSED(n);
if (curwp->w_markp == NULL)
{
mlwrite("No mark in this window");
return FALSE;
}
odotp = curwp->w_dotp;
odoto = curwp->w_doto;
curwp->w_dotp = curwp->w_markp;
curwp->w_doto = curwp->w_marko;
curwp->w_markp = odotp;
curwp->w_marko = odoto;
curwp->w_flag |= WFMOVE;
return TRUE;
}
/*
Go to a specific line, mostly for looking up errors in C programs,
which give the error a line number. If an argument is present, then
it is the line number, else prompt for a line number to use.
*/
int gotoline(int f, int n)
{
ELINE *clp;
char buf[32];
if (f == FALSE)
{
buf[0] = '\0';
mlreply("Goto line: ", buf, ((uint) sizeof(buf)));
if (buf[0] == '\0')
return ABORT;
n = atoi(buf);
}
clp = lforw(curbp->b_linep); /* "clp" is first line */
while (n > 1)
{
if (lforw(clp) == curbp->b_linep)
break;
clp = lforw(clp);
--n;
}
curwp->w_dotp = clp;
curwp->w_doto = 0;
curwp->w_flag |= WFMOVE;
return TRUE;
}