1 /*
2  * Copyright (c) 2021, 2024 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "compat.h"
18 
19 #include <stdlib.h>
20 #include <string.h>
21 
22 #include "hist.h"
23 
24 struct hist {
25 	TAILQ_HEAD(mhist, hist_item)	 head;
26 	int				 flags;
27 	size_t				 size;
28 	ssize_t				 off;
29 	struct hist_item		*cur;
30 };
31 
32 struct hist_item {
33 	char			*str;
34 	size_t			 line_off;
35 	size_t			 current_off;
36 	TAILQ_ENTRY(hist_item)	 entries;
37 };
38 
39 struct hist *
40 hist_new(int flags)
41 {
42 	struct hist	*hist;
43 
44 	if ((hist = calloc(1, sizeof(*hist))) == NULL)
45 		return (NULL);
46 
47 	TAILQ_INIT(&hist->head);
48 	hist->flags = flags;
49 	hist->off = -1;
50 	return (hist);
51 }
52 
53 void
54 hist_free(struct hist *hist)
55 {
56 	if (hist == NULL)
57 		return;
58 
59 	hist_erase(hist);
60 	free(hist);
61 }
62 
63 static void
64 hist_erase_from(struct hist *hist, struct hist_item *h)
65 {
66 	struct hist_item	*next;
67 
68 	while (h != NULL) {
69 		next = TAILQ_NEXT(h, entries);
70 
71 		hist->size--;
72 		TAILQ_REMOVE(&hist->head, h, entries);
73 		free(h->str);
74 		free(h);
75 		h = next;
76 	}
77 }
78 
79 void
80 hist_erase(struct hist *hist)
81 {
82 	hist_erase_from(hist, TAILQ_FIRST(&hist->head));
83 
84 	hist->size = 0;
85 	hist->off = -1;
86 	hist->cur = NULL;
87 }
88 
89 size_t
90 hist_size(struct hist *hist)
91 {
92 	return (hist->size);
93 }
94 
95 size_t
96 hist_off(struct hist *hist)
97 {
98 	if (hist->off == -1)
99 		return (0);
100 	return (hist->off);
101 }
102 
103 const char *
104 hist_cur(struct hist *hist)
105 {
106 	if (hist->cur == NULL)
107 		return (NULL);
108 	return (hist->cur->str);
109 }
110 
111 int
112 hist_cur_offs(struct hist *hist, size_t *line, size_t *curr)
113 {
114 	*line = 0;
115 	*curr = 0;
116 
117 	if (hist->cur == NULL)
118 		return (-1);
119 
120 	*line = hist->cur->line_off;
121 	*curr = hist->cur->current_off;
122 	return (0);
123 }
124 
125 int
126 hist_set_cur(struct hist *hist, const char *str)
127 {
128 	char		*d;
129 
130 	if (hist->cur == NULL)
131 		return (-1);
132 
133 	if ((d = strdup(str)) == NULL)
134 		return (-1);
135 
136 	free(hist->cur->str);
137 	hist->cur->str = d;
138 	return (0);
139 }
140 
141 int
142 hist_set_offs(struct hist *hist, size_t line, size_t curr)
143 {
144 	if (hist->cur == NULL)
145 		return (-1);
146 
147 	hist->cur->line_off = line;
148 	hist->cur->current_off = line;
149 	return (0);
150 }
151 
152 const char *
153 hist_nth(struct hist *hist, size_t n)
154 {
155 	size_t			 i;
156 	struct hist_item	*h;
157 
158 	i = 0;
159 	TAILQ_FOREACH(h, &hist->head, entries) {
160 		if (i++ == n)
161 			return (h->str);
162 	}
163 	return (NULL);
164 }
165 
166 const char *
167 hist_prev(struct hist *hist)
168 {
169 	struct hist_item	*h;
170 	int			 wrap = hist->flags & HIST_WRAP;
171 
172 	if (hist->cur == NULL && !wrap)
173 		return (NULL);
174 
175 	if (hist->cur == NULL ||
176 	    (h = TAILQ_PREV(hist->cur, mhist, entries)) == NULL) {
177 		if (!wrap || (h = TAILQ_LAST(&hist->head, mhist)) == NULL)
178 			return (NULL);
179 		hist->off = hist->size - 1;
180 	} else
181 		hist->off--;
182 
183 	hist->cur = h;
184 	return (h->str);
185 }
186 
187 const char *
188 hist_next(struct hist *hist)
189 {
190 	struct hist_item	*h;
191 	int			 wrap = hist->flags & HIST_WRAP;
192 
193 	if (hist->cur == NULL && !wrap)
194 		return (NULL);
195 
196 	if (hist->cur == NULL ||
197 	    (h = TAILQ_NEXT(hist->cur, entries)) == NULL) {
198 		if (!wrap || (h = TAILQ_FIRST(&hist->head)) == NULL)
199 			return (NULL);
200 		hist->off = 0;
201 	} else
202 		hist->off++;
203 
204 	hist->cur = h;
205 	return (h->str);
206 }
207 
208 void
209 hist_seek_start(struct hist *hist)
210 {
211 	hist->off = -1;
212 	hist->cur = NULL;
213 }
214 
215 int
216 hist_push(struct hist *hist, const char *str)
217 {
218 	struct hist_item	*h;
219 
220 	if ((h = calloc(1, sizeof(*h))) == NULL)
221 		return (-1);
222 
223 	if ((h->str = strdup(str)) == NULL) {
224 		free(h);
225 		return (-1);
226 	}
227 
228 	if (hist->cur != NULL)
229 		hist_erase_from(hist, TAILQ_NEXT(hist->cur, entries));
230 	hist->cur = h;
231 	hist->off++;
232 	hist->size++;
233 	TAILQ_INSERT_TAIL(&hist->head, h, entries);
234 	return (0);
235 }
236 
237 int
238 hist_prepend(struct hist *hist, const char *str)
239 {
240 	struct hist_item	*h;
241 
242 	if (hist->cur == NULL)
243 		return (-1);
244 
245 	if ((h = calloc(1, sizeof(*h))) == NULL)
246 		return (-1);
247 
248 	if ((h->str = strdup(str)) == NULL) {
249 		free(h);
250 		return (-1);
251 	}
252 
253 	hist->size++;
254 	hist->off++;
255 	TAILQ_INSERT_BEFORE(hist->cur, h, entries);
256 	return (0);
257 }
258 
259 int
260 hist_append(struct hist *hist, const char *str)
261 {
262 	struct hist_item	*h;
263 
264 	/*
265 	 * Not sure.  The minibuffer needs to append even when there
266 	 * are no items.
267 	 */
268 	if (hist->cur == NULL && !(hist->flags & HIST_WRAP))
269 		return (-1);
270 
271 	if ((h = calloc(1, sizeof(*h))) == NULL)
272 		return (-1);
273 
274 	if ((h->str = strdup(str)) == NULL) {
275 		free(h);
276 		return (-1);
277 	}
278 
279 	hist->size++;
280 	TAILQ_INSERT_TAIL(&hist->head, h, entries);
281 	return (0);
282 }