1 /* $OpenBSD: buf.c,v 1.25 2024/04/23 13:34:50 jsg Exp $ */
2 /* $NetBSD: buf.c,v 1.15 1995/04/23 10:07:28 cgd Exp $ */
3
4 /* buf.c: This file contains the scratch-file buffer routines for the
5 ed line editor. */
6 /*-
7 * Copyright (c) 1993 Andrew Moore, Talke Studio.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/types.h>
33 #include <sys/stat.h>
34
35 #include <limits.h>
36 #include <regex.h>
37 #include <signal.h>
38 #include <stdlib.h>
39 #include <stdio.h>
40 #include <string.h>
41 #include <unistd.h>
42
43 #include "ed.h"
44
45
46 static FILE *sfp; /* scratch file pointer */
47 static off_t sfseek; /* scratch file position */
48 static int seek_write; /* seek before writing */
49 static line_t buffer_head; /* incore buffer */
50
51 /* get_sbuf_line: get a line of text from the scratch file; return pointer
52 to the text */
53 char *
get_sbuf_line(line_t * lp)54 get_sbuf_line(line_t *lp)
55 {
56 static char *sfbuf = NULL; /* buffer */
57 static int sfbufsz = 0; /* buffer size */
58 int len;
59
60 if (lp == &buffer_head)
61 return NULL;
62 seek_write = 1; /* force seek on write */
63 /* out of position */
64 if (sfseek != lp->seek) {
65 sfseek = lp->seek;
66 if (fseeko(sfp, sfseek, SEEK_SET) == -1) {
67 perror(NULL);
68 seterrmsg("cannot seek temp file");
69 return NULL;
70 }
71 }
72 len = lp->len;
73 REALLOC(sfbuf, sfbufsz, len + 1, NULL);
74 if (fread(sfbuf, sizeof(char), len, sfp) != len) {
75 perror(NULL);
76 seterrmsg("cannot read temp file");
77 return NULL;
78 }
79 sfseek += len; /* update file position */
80 sfbuf[len] = '\0';
81 return sfbuf;
82 }
83
84
85 /* put_sbuf_line: write a line of text to the scratch file and add a line node
86 to the editor buffer; return a pointer to the end of the text */
87 char *
put_sbuf_line(char * cs)88 put_sbuf_line(char *cs)
89 {
90 line_t *lp;
91 int len;
92 char *s;
93
94 if ((lp = malloc(sizeof(line_t))) == NULL) {
95 perror(NULL);
96 seterrmsg("out of memory");
97 return NULL;
98 }
99 /* assert: cs is '\n' terminated */
100 for (s = cs; *s != '\n'; s++)
101 ;
102 if (s - cs >= LINECHARS) {
103 seterrmsg("line too long");
104 free(lp);
105 return NULL;
106 }
107 len = s - cs;
108 /* out of position */
109 if (seek_write) {
110 if (fseek(sfp, 0L, SEEK_END) == -1) {
111 perror(NULL);
112 seterrmsg("cannot seek temp file");
113 free(lp);
114 return NULL;
115 }
116 sfseek = ftello(sfp);
117 seek_write = 0;
118 }
119 /* assert: SPL1() */
120 if (fwrite(cs, sizeof(char), len, sfp) != len) {
121 sfseek = -1;
122 perror(NULL);
123 seterrmsg("cannot write temp file");
124 free(lp);
125 return NULL;
126 }
127 lp->len = len;
128 lp->seek = sfseek;
129 add_line_node(lp);
130 sfseek += len; /* update file position */
131 return ++s;
132 }
133
134
135 /* add_line_node: add a line node in the editor buffer after the current line */
136 void
add_line_node(line_t * lp)137 add_line_node(line_t *lp)
138 {
139 line_t *cp;
140
141 /* this get_addressed_line_node last! */
142 cp = get_addressed_line_node(current_addr);
143 INSQUE(lp, cp);
144 addr_last++;
145 current_addr++;
146 }
147
148
149 /* get_line_node_addr: return line number of pointer */
150 int
get_line_node_addr(line_t * lp)151 get_line_node_addr(line_t *lp)
152 {
153 line_t *cp = &buffer_head;
154 int n = 0;
155
156 while (cp != lp && (cp = cp->q_forw) != &buffer_head)
157 n++;
158 if (n && cp == &buffer_head) {
159 seterrmsg("invalid address");
160 return ERR;
161 }
162 return n;
163 }
164
165
166 /* get_addressed_line_node: return pointer to a line node in the editor buffer */
167 line_t *
get_addressed_line_node(int n)168 get_addressed_line_node(int n)
169 {
170 static line_t *lp = &buffer_head;
171 static int on = 0;
172
173 SPL1();
174 if (n > on) {
175 if (n <= (on + addr_last) >> 1)
176 for (; on < n; on++)
177 lp = lp->q_forw;
178 else {
179 lp = buffer_head.q_back;
180 for (on = addr_last; on > n; on--)
181 lp = lp->q_back;
182 }
183 } else {
184 if (n >= on >> 1)
185 for (; on > n; on--)
186 lp = lp->q_back;
187 else {
188 lp = &buffer_head;
189 for (on = 0; on < n; on++)
190 lp = lp->q_forw;
191 }
192 }
193 SPL0();
194 return lp;
195 }
196
197
198 extern int newline_added;
199
200 #define SCRATCH_TEMPLATE "/tmp/ed.XXXXXXXXXX"
201 static char sfn[sizeof(SCRATCH_TEMPLATE)+1] = ""; /* scratch file name */
202
203 /* open_sbuf: open scratch file */
204 int
open_sbuf(void)205 open_sbuf(void)
206 {
207 int fd = -1;
208
209 isbinary = newline_added = 0;
210 strlcpy(sfn, SCRATCH_TEMPLATE, sizeof sfn);
211 if ((fd = mkstemp(sfn)) == -1 ||
212 (sfp = fdopen(fd, "w+")) == NULL) {
213 if (fd != -1)
214 close(fd);
215 perror(sfn);
216 seterrmsg("cannot open temp file");
217 return ERR;
218 }
219 return 0;
220 }
221
222
223 /* close_sbuf: close scratch file */
224 int
close_sbuf(void)225 close_sbuf(void)
226 {
227 if (sfp) {
228 if (fclose(sfp) == EOF) {
229 perror(sfn);
230 seterrmsg("cannot close temp file");
231 return ERR;
232 }
233 sfp = NULL;
234 unlink(sfn);
235 }
236 sfseek = seek_write = 0;
237 return 0;
238 }
239
240
241 /* quit: remove_lines scratch file and exit */
242 void
quit(int n)243 quit(int n)
244 {
245 if (sfp) {
246 fclose(sfp);
247 unlink(sfn);
248 }
249 exit(n);
250 }
251
252
253 static unsigned char ctab[256]; /* character translation table */
254
255 /* init_buffers: open scratch buffer; initialize line queue */
256 void
init_buffers(void)257 init_buffers(void)
258 {
259 int i = 0;
260
261 /* Read stdin one character at a time to avoid i/o contention
262 with shell escapes invoked by nonterminal input, e.g.,
263 ed - <<EOF
264 !cat
265 hello, world
266 EOF */
267 setvbuf(stdin, NULL, _IONBF, 0);
268 if (open_sbuf() < 0)
269 quit(2);
270 REQUE(&buffer_head, &buffer_head);
271 for (i = 0; i < 256; i++)
272 ctab[i] = i;
273 }
274
275
276 /* translit_text: translate characters in a string */
277 char *
translit_text(char * s,int len,int from,int to)278 translit_text(char *s, int len, int from, int to)
279 {
280 static int i = 0;
281
282 unsigned char *us;
283
284 ctab[i] = i; /* restore table to initial state */
285 ctab[i = from] = to;
286 for (us = (unsigned char *) s; len-- > 0; us++)
287 *us = ctab[*us];
288 return s;
289 }
290