1/*
2 * Copyright (C) 1984-2012 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, see the README file.
8 */
9
10
11#include "less.h"
12
13extern IFILE curr_ifile;
14extern int sc_height;
15extern int jump_sline;
16
17/*
18 * A mark is an ifile (input file) plus a position within the file.
19 */
20struct mark {
21 IFILE m_ifile;
22 struct scrpos m_scrpos;
23};
24
25/*
26 * The table of marks.
27 * Each mark is identified by a lowercase or uppercase letter.
28 * The final one is lmark, for the "last mark"; addressed by the apostrophe.
29 */
30#define NMARKS ((2*26)+1) /* a-z, A-Z, lastmark */
31#define LASTMARK (NMARKS-1)
32static struct mark marks[NMARKS];
33
34/*
35 * Initialize the mark table to show no marks are set.
36 */
37 public void
38init_mark()
39{
40 int i;
41
42 for (i = 0; i < NMARKS; i++)
43 marks[i].m_scrpos.pos = NULL_POSITION;
44}
45
46/*
47 * See if a mark letter is valid (between a and z).
48 */
49 static struct mark *
50getumark(c)
51 int c;
52{
53 if (c >= 'a' && c <= 'z')
54 return (&marks[c-'a']);
55
56 if (c >= 'A' && c <= 'Z')
57 return (&marks[c-'A'+26]);
58
59 error("Invalid mark letter", NULL_PARG);
60 return (NULL);
61}
62
63/*
64 * Get the mark structure identified by a character.
65 * The mark struct may come either from the mark table
66 * or may be constructed on the fly for certain characters like ^, $.
67 */
68 static struct mark *
69getmark(c)
70 int c;
71{
72 register struct mark *m;
73 static struct mark sm;
74
75 switch (c)
76 {
77 case '^':
78 /*
79 * Beginning of the current file.
80 */
81 m = &sm;
82 m->m_scrpos.pos = ch_zero();
83 m->m_scrpos.ln = 0;
84 m->m_ifile = curr_ifile;
85 break;
86 case '$':
87 /*
88 * End of the current file.
89 */
90 if (ch_end_seek())
91 {
92 error("Cannot seek to end of file", NULL_PARG);
93 return (NULL);
94 }
95 m = &sm;
96 m->m_scrpos.pos = ch_tell();
97 m->m_scrpos.ln = sc_height-1;
98 m->m_ifile = curr_ifile;
99 break;
100 case '.':
101 /*
102 * Current position in the current file.
103 */
104 m = &sm;
105 get_scrpos(&m->m_scrpos);
106 m->m_ifile = curr_ifile;
107 break;
108 case '\'':
109 /*
110 * The "last mark".
111 */
112 m = &marks[LASTMARK];
113 break;
114 default:
115 /*
116 * Must be a user-defined mark.
117 */
118 m = getumark(c);
119 if (m == NULL)
120 break;
121 if (m->m_scrpos.pos == NULL_POSITION)
122 {
123 error("Mark not set", NULL_PARG);
124 return (NULL);
125 }
126 break;
127 }
128 return (m);
129}
130
131/*
132 * Is a mark letter is invalid?
133 */
134 public int
135badmark(c)
136 int c;
137{
138 return (getmark(c) == NULL);
139}
140
141/*
142 * Set a user-defined mark.
143 */
144 public void
145setmark(c)
146 int c;
147{
148 register struct mark *m;
149 struct scrpos scrpos;
150
151 m = getumark(c);
152 if (m == NULL)
153 return;
154 get_scrpos(&scrpos);
155 m->m_scrpos = scrpos;
156 m->m_ifile = curr_ifile;
157}
158
159/*
160 * Set lmark (the mark named by the apostrophe).
161 */
162 public void
163lastmark()
164{
165 struct scrpos scrpos;
166
167 if (ch_getflags() & CH_HELPFILE)
168 return;
169 get_scrpos(&scrpos);
170 if (scrpos.pos == NULL_POSITION)
171 return;
172 marks[LASTMARK].m_scrpos = scrpos;
173 marks[LASTMARK].m_ifile = curr_ifile;
174}
175
176/*
177 * Go to a mark.
178 */
179 public void
180gomark(c)
181 int c;
182{
183 register struct mark *m;
184 struct scrpos scrpos;
185
186 m = getmark(c);
187 if (m == NULL)
188 return;
189
190 /*
191 * If we're trying to go to the lastmark and
192 * it has not been set to anything yet,
193 * set it to the beginning of the current file.
194 */
195 if (m == &marks[LASTMARK] && m->m_scrpos.pos == NULL_POSITION)
196 {
197 m->m_ifile = curr_ifile;
198 m->m_scrpos.pos = ch_zero();
199 m->m_scrpos.ln = jump_sline;
200 }
201
202 /*
203 * If we're using lmark, we must save the screen position now,
204 * because if we call edit_ifile() below, lmark will change.
205 * (We save the screen position even if we're not using lmark.)
206 */
207 scrpos = m->m_scrpos;
208 if (m->m_ifile != curr_ifile)
209 {
210 /*
211 * Not in the current file; edit the correct file.
212 */
213 if (edit_ifile(m->m_ifile))
214 return;
215 }
216
217 jump_loc(scrpos.pos, scrpos.ln);
218}
219
220/*
221 * Return the position associated with a given mark letter.
222 *
223 * We don't return which screen line the position
224 * is associated with, but this doesn't matter much,
225 * because it's always the first non-blank line on the screen.
226 */
227 public POSITION
228markpos(c)
229 int c;
230{
231 register struct mark *m;
232
233 m = getmark(c);
234 if (m == NULL)
235 return (NULL_POSITION);
236
237 if (m->m_ifile != curr_ifile)
238 {
239 error("Mark not in current file", NULL_PARG);
240 return (NULL_POSITION);
241 }
242 return (m->m_scrpos.pos);
243}
244
245/*
246 * Clear the marks associated with a specified ifile.
247 */
248 public void
249unmark(ifile)
250 IFILE ifile;
251{
252 int i;
253
254 for (i = 0; i < NMARKS; i++)
255 if (marks[i].m_ifile == ifile)
256 marks[i].m_scrpos.pos = NULL_POSITION;
257}