xref: /netbsd/bin/ed/buf.c (revision 7cc84c81)
1 /*	$NetBSD: buf.c,v 1.27 2014/03/23 05:06:42 dholland Exp $	*/
2 
3 /* buf.c: This file contains the scratch-file buffer routines for the
4    ed line editor. */
5 /*-
6  * Copyright (c) 1993 Andrew Moore, Talke Studio.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 #ifndef lint
33 #if 0
34 static char *rcsid = "@(#)buf.c,v 1.4 1994/02/01 00:34:35 alm Exp";
35 #else
36 __RCSID("$NetBSD: buf.c,v 1.27 2014/03/23 05:06:42 dholland Exp $");
37 #endif
38 #endif /* not lint */
39 
40 #include <sys/file.h>
41 #include <sys/stat.h>
42 
43 #include <paths.h>
44 #include <stdio.h>
45 #include <err.h>
46 
47 #include "ed.h"
48 
49 
50 FILE *sfp;				/* scratch file pointer */
51 off_t sfseek;				/* scratch file position */
52 int seek_write;				/* seek before writing */
53 line_t buffer_head;			/* incore buffer */
54 
55 /* get_sbuf_line: get a line of text from the scratch file; return pointer
56    to the text */
57 char *
get_sbuf_line(line_t * lp)58 get_sbuf_line(line_t *lp)
59 {
60 	static char *sfbuf = NULL;	/* buffer */
61 	static int sfbufsz = 0;		/* buffer size */
62 
63 	int len, ct;
64 
65 	if (lp == &buffer_head)
66 		return NULL;
67 	seek_write = 1;				/* force seek on write */
68 	/* out of position */
69 	if (sfseek != lp->seek) {
70 		sfseek = lp->seek;
71 		if (fseek(sfp, sfseek, SEEK_SET) < 0) {
72 			fprintf(stderr, "%s\n", strerror(errno));
73 			seterrmsg("cannot seek temp file");
74 			return NULL;
75 		}
76 	}
77 	len = lp->len;
78 	REALLOC(sfbuf, sfbufsz, len + 1, NULL);
79 	if ((ct = fread(sfbuf, sizeof(char), len, sfp)) <  0 || ct != len) {
80 		fprintf(stderr, "%s\n", strerror(errno));
81 		seterrmsg("cannot read temp file");
82 		return NULL;
83 	}
84 	sfseek += len;				/* update file position */
85 	sfbuf[len] = '\0';
86 	return sfbuf;
87 }
88 
89 
90 /* put_sbuf_line: write a line of text to the scratch file and add a line node
91    to the editor buffer;  return a pointer to the end of the text */
92 char *
put_sbuf_line(char * cs)93 put_sbuf_line(char *cs)
94 {
95 	line_t *lp;
96 	int len, ct;
97 	char *s;
98 
99 	if ((lp = (line_t *) malloc(sizeof(line_t))) == NULL) {
100 		fprintf(stderr, "%s\n", strerror(errno));
101 		seterrmsg("out of memory");
102 		return NULL;
103 	}
104 	/* assert: cs is '\n' terminated */
105 	for (s = cs; *s != '\n'; s++)
106 		;
107 	if (s - cs >= LINECHARS) {
108 		seterrmsg("line too long");
109 		free(lp);
110 		return NULL;
111 	}
112 	len = s - cs;
113 	/* out of position */
114 	if (seek_write) {
115 		if (fseek(sfp, 0L, SEEK_END) < 0) {
116 			fprintf(stderr, "%s\n", strerror(errno));
117 			seterrmsg("cannot seek temp file");
118 			free(lp);
119 			return NULL;
120 		}
121 		sfseek = ftell(sfp);
122 		seek_write = 0;
123 	}
124 	/* assert: SPL1() */
125 	if ((ct = fwrite(cs, sizeof(char), len, sfp)) < 0 || ct != len) {
126 		sfseek = -1;
127 		fprintf(stderr, "%s\n", strerror(errno));
128 		seterrmsg("cannot write temp file");
129 		free(lp);
130 		return NULL;
131 	}
132 	lp->len = len;
133 	lp->seek  = sfseek;
134 	add_line_node(lp);
135 	sfseek += len;			/* update file position */
136 	return ++s;
137 }
138 
139 
140 /* add_line_node: add a line node in the editor buffer after the current line */
141 void
add_line_node(line_t * lp)142 add_line_node(line_t *lp)
143 {
144 	line_t *cp;
145 
146 	cp = get_addressed_line_node(current_addr); /* this get_addressed_line_node last! */
147 	INSQUE(lp, cp);
148 	addr_last++;
149 	current_addr++;
150 }
151 
152 
153 /* get_line_node_addr: return line number of pointer */
154 long
get_line_node_addr(line_t * lp)155 get_line_node_addr(line_t *lp)
156 {
157 	line_t *cp = &buffer_head;
158 	long n = 0;
159 
160 	while (cp != lp && (cp = cp->q_forw) != &buffer_head)
161 		n++;
162 	if (n && cp == &buffer_head) {
163 		seterrmsg("invalid address");
164 		return ERR;
165 	}
166 	return n;
167 }
168 
169 
170 /* get_addressed_line_node: return pointer to a line node in the editor buffer */
171 line_t *
get_addressed_line_node(long n)172 get_addressed_line_node(long n)
173 {
174 	static line_t *lp = &buffer_head;
175 	static long on = 0;
176 
177 	SPL1();
178 	if (n > on) {
179 		if (n <= (on + addr_last) >> 1) {
180 			for (; on < n; on++)
181 				lp = lp->q_forw;
182 		} else {
183 			lp = buffer_head.q_back;
184 			for (on = addr_last; on > n; on--)
185 				lp = lp->q_back;
186 		}
187 	} else {
188 		if (n >= on >> 1) {
189 			for (; on > n; on--)
190 				lp = lp->q_back;
191 		} else {
192 			lp = &buffer_head;
193 			for (on = 0; on < n; on++)
194 				lp = lp->q_forw;
195 		}
196 	}
197 	SPL0();
198 	return lp;
199 }
200 
201 
202 char *sfn = NULL;				/* scratch file name */
203 
204 /* open_sbuf: open scratch file */
205 int
open_sbuf(void)206 open_sbuf(void)
207 {
208 	int u, fd;
209 	const char *tmp;
210 	size_t s;
211 
212 	isbinary = newline_added = 0;
213 	fd = -1;
214 	u = umask(077);
215 
216 	if ((tmp = getenv("TMPDIR")) == NULL)
217 		tmp = _PATH_TMP;
218 
219 	if ((s = strlen(tmp)) == 0 || tmp[s - 1] == '/')
220 		(void)asprintf(&sfn, "%sed.XXXXXX", tmp);
221 	else
222 		(void)asprintf(&sfn, "%s/ed.XXXXXX", tmp);
223 	if (sfn == NULL) {
224 		warn(NULL);
225 		seterrmsg("could not allocate memory");
226 		umask(u);
227 		return ERR;
228 	}
229 
230 
231 	if ((fd = mkstemp(sfn)) == -1 || (sfp = fdopen(fd, "w+")) == NULL) {
232 		if (fd != -1)
233 			close(fd);
234 		warn("%s", sfn);
235 		seterrmsg("cannot open temp file");
236 		umask(u);
237 		return ERR;
238 	}
239 	umask(u);
240 	return 0;
241 }
242 
243 
244 /* close_sbuf: close scratch file */
245 int
close_sbuf(void)246 close_sbuf(void)
247 {
248 	if (sfp) {
249 		if (fclose(sfp) < 0) {
250 			fprintf(stderr, "%s: %s\n", sfn, strerror(errno));
251 			seterrmsg("cannot close temp file");
252 			return ERR;
253 		}
254 		sfp = NULL;
255 		if (sfn) {
256 			unlink(sfn);
257 			free(sfn);
258 			sfn = NULL;
259 		}
260 	}
261 	sfseek = seek_write = 0;
262 	return 0;
263 }
264 
265 
266 /* quit: remove_lines scratch file and exit */
267 void
quit(int n)268 quit(int n)
269 {
270 	if (sfp) {
271 		fclose(sfp);
272 		if (sfn) {
273 			unlink(sfn);
274 			free(sfn);
275 			sfn = NULL;
276 		}
277 	}
278 	exit(n);
279 	/* NOTREACHED */
280 }
281 
282 
283 unsigned char ctab[256];		/* character translation table */
284 
285 /* init_buffers: open scratch buffer; initialize line queue */
286 void
init_buffers(void)287 init_buffers(void)
288 {
289 	int i = 0;
290 
291 	/* Read stdin one character at a time to avoid i/o contention
292 	   with shell escapes invoked by nonterminal input, e.g.,
293 	   ed - <<EOF
294 	   !cat
295 	   hello, world
296 	   EOF */
297 	setbuffer(stdin, stdinbuf, 1);
298 	if (open_sbuf() < 0)
299 		quit(2);
300 	REQUE(&buffer_head, &buffer_head);
301 	for (i = 0; i < 256; i++)
302 		ctab[i] = i;
303 }
304 
305 
306 /* translit_text: translate characters in a string */
307 char *
translit_text(char * s,int len,int from,int to)308 translit_text(char *s, int len, int from, int to)
309 {
310 	static int i = 0;
311 
312 	unsigned char *us;
313 
314 	ctab[i] = i;			/* restore table to initial state */
315 	ctab[i = from] = to;
316 	for (us = (unsigned char *) s; len-- > 0; us++)
317 		*us = ctab[*us];
318 	return s;
319 }
320