1/*
2 * Copyright (C) 1984-2011 Mark Nudelman
3 *
4 * You may distribute under the terms of either the GNU General Public
5 * License or the Less License, as specified in the README file.
6 *
7 * For more information about less, or for information on how to
8 * contact the author, see the README file.
9 */
10
11
12#include "less.h"
13
14extern IFILE curr_ifile;
15extern int sc_height;
16extern int jump_sline;
17
18/*
19 * A mark is an ifile (input file) plus a position within the file.
20 */
21struct mark {
22 IFILE m_ifile;
23 struct scrpos m_scrpos;
24};
25
26/*
27 * The table of marks.
28 * Each mark is identified by a lowercase or uppercase letter.
29 * The final one is lmark, for the "last mark"; addressed by the apostrophe.
30 */
31#define NMARKS ((2*26)+1) /* a-z, A-Z, lastmark */
32#define LASTMARK (NMARKS-1)
33static struct mark marks[NMARKS];
34
35/*
36 * Initialize the mark table to show no marks are set.
37 */
38 public void
39init_mark()
40{
41 int i;
42
43 for (i = 0; i < NMARKS; i++)
44 marks[i].m_scrpos.pos = NULL_POSITION;
45}
46
47/*
48 * See if a mark letter is valid (between a and z).
49 */
50 static struct mark *
51getumark(c)
52 int c;
53{
54 if (c >= 'a' && c <= 'z')
55 return (&marks[c-'a']);
56
57 if (c >= 'A' && c <= 'Z')
58 return (&marks[c-'A'+26]);
59
60 error("Invalid mark letter", NULL_PARG);
61 return (NULL);
62}
63
64/*
65 * Get the mark structure identified by a character.
66 * The mark struct may come either from the mark table
67 * or may be constructed on the fly for certain characters like ^, $.
68 */
69 static struct mark *
70getmark(c)
71 int c;
72{
73 register struct mark *m;
74 static struct mark sm;
75
76 switch (c)
77 {
78 case '^':
79 /*
80 * Beginning of the current file.
81 */
82 m = &sm;
83 m->m_scrpos.pos = ch_zero();
84 m->m_scrpos.ln = 0;
85 m->m_ifile = curr_ifile;
86 break;
87 case '$':
88 /*
89 * End of the current file.
90 */
91 if (ch_end_seek())
92 {
93 error("Cannot seek to end of file", NULL_PARG);
94 return (NULL);
95 }
96 m = &sm;
97 m->m_scrpos.pos = ch_tell();
98 m->m_scrpos.ln = sc_height-1;
99 m->m_ifile = curr_ifile;
100 break;
101 case '.':
102 /*
103 * Current position in the current file.
104 */
105 m = &sm;
106 get_scrpos(&m->m_scrpos);
107 m->m_ifile = curr_ifile;
108 break;
109 case '\'':
110 /*
111 * The "last mark".
112 */
113 m = &marks[LASTMARK];
114 break;
115 default:
116 /*
117 * Must be a user-defined mark.
118 */
119 m = getumark(c);
120 if (m == NULL)
121 break;
122 if (m->m_scrpos.pos == NULL_POSITION)
123 {
124 error("Mark not set", NULL_PARG);
125 return (NULL);
126 }
127 break;
128 }
129 return (m);
130}
131
132#if PIPEC
133/*
134 * Is a mark letter is invalid?
135 */
136 public int
137badmark(c)
138 int c;
139{
140 return (getmark(c) == NULL);
141}
142#endif
143
144/*
145 * Set a user-defined mark.
146 */
147 public void
148setmark(c)
149 int c;
150{
151 register struct mark *m;
152 struct scrpos scrpos;
153
154 m = getumark(c);
155 if (m == NULL)
156 return;
157 get_scrpos(&scrpos);
158 m->m_scrpos = scrpos;
159 m->m_ifile = curr_ifile;
160}
161
162/*
163 * Set lmark (the mark named by the apostrophe).
164 */
165 public void
166lastmark()
167{
168 struct scrpos scrpos;
169
170 if (ch_getflags() & CH_HELPFILE)
171 return;
172 get_scrpos(&scrpos);
173 if (scrpos.pos == NULL_POSITION)
174 return;
175 marks[LASTMARK].m_scrpos = scrpos;
176 marks[LASTMARK].m_ifile = curr_ifile;
177}
178
179/*
180 * Go to a mark.
181 */
182 public void
183gomark(c)
184 int c;
185{
186 register struct mark *m;
187 struct scrpos scrpos;
188
189 m = getmark(c);
190 if (m == NULL)
191 return;
192
193 /*
194 * If we're trying to go to the lastmark and
195 * it has not been set to anything yet,
196 * set it to the beginning of the current file.
197 */
198 if (m == &marks[LASTMARK] && m->m_scrpos.pos == NULL_POSITION)
199 {
200 m->m_ifile = curr_ifile;
201 m->m_scrpos.pos = ch_zero();
202 m->m_scrpos.ln = jump_sline;
203 }
204
205 /*
206 * If we're using lmark, we must save the screen position now,
207 * because if we call edit_ifile() below, lmark will change.
208 * (We save the screen position even if we're not using lmark.)
209 */
210 scrpos = m->m_scrpos;
211 if (m->m_ifile != curr_ifile)
212 {
213 /*
214 * Not in the current file; edit the correct file.
215 */
216 if (edit_ifile(m->m_ifile))
217 return;
218 }
219
220 jump_loc(scrpos.pos, scrpos.ln);
221}
222
223#if PIPEC
224/*
225 * Return the position associated with a given mark letter.
226 *
227 * We don't return which screen line the position
228 * is associated with, but this doesn't matter much,
229 * because it's always the first non-blank line on the screen.
230 */
231 public POSITION
232markpos(c)
233 int c;
234{
235 register struct mark *m;
236
237 m = getmark(c);
238 if (m == NULL)
239 return (NULL_POSITION);
240
241 if (m->m_ifile != curr_ifile)
242 {
243 error("Mark not in current file", NULL_PARG);
244 return (NULL_POSITION);
245 }
246 return (m->m_scrpos.pos);
247}
248#endif /* PIPEC */
249
250/*
251 * Clear the marks associated with a specified ifile.
252 */
253 public void
254unmark(ifile)
255 IFILE ifile;
256{
257 int i;
258
259 for (i = 0; i < NMARKS; i++)
260 if (marks[i].m_ifile == ifile)
261 marks[i].m_scrpos.pos = NULL_POSITION;
262}