xref: /openbsd/usr.bin/mail/edit.c (revision 3aaa63eb)
1 /*	$OpenBSD: edit.c,v 1.21 2019/06/28 13:35:01 deraadt Exp $	*/
2 /*	$NetBSD: edit.c,v 1.5 1996/06/08 19:48:20 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1980, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/types.h>
34 #include <sys/wait.h>
35 
36 #include "rcv.h"
37 #include <errno.h>
38 #include <fcntl.h>
39 #include "extern.h"
40 
41 int editit(const char *, const char *);
42 
43 /*
44  * Mail -- a mail program
45  *
46  * Perform message editing functions.
47  */
48 
49 /*
50  * Edit a message list.
51  */
52 int
editor(void * v)53 editor(void *v)
54 {
55 	int *msgvec = v;
56 
57 	return(edit1(msgvec, 'e'));
58 }
59 
60 /*
61  * Invoke the visual editor on a message list.
62  */
63 int
visual(void * v)64 visual(void *v)
65 {
66 	int *msgvec = v;
67 
68 	return(edit1(msgvec, 'v'));
69 }
70 
71 /*
72  * Edit a message by writing the message into a funnily-named file
73  * (which should not exist) and forking an editor on it.
74  * We get the editor from the stuff above.
75  */
76 int
edit1(int * msgvec,int type)77 edit1(int *msgvec, int type)
78 {
79 	int nl = 0, c, i;
80 	FILE *fp;
81 	struct sigaction oact;
82 	sigset_t oset;
83 	struct message *mp;
84 	off_t size;
85 
86 	/*
87 	 * Deal with each message to be edited . . .
88 	 */
89 	for (i = 0; msgvec[i] && i < msgCount; i++) {
90 		if (i > 0) {
91 			char buf[100];
92 			char *p;
93 
94 			printf("Edit message %d [ynq]? ", msgvec[i]);
95 			if (fgets(buf, sizeof(buf), stdin) == NULL)
96 				break;
97 			for (p = buf; *p == ' ' || *p == '\t'; p++)
98 				;
99 			if (*p == 'q')
100 				break;
101 			if (*p == 'n')
102 				continue;
103 		}
104 		dot = mp = &message[msgvec[i] - 1];
105 		touch(mp);
106 		(void)ignoresig(SIGINT, &oact, &oset);
107 		fp = run_editor(setinput(mp), (off_t)mp->m_size, type, readonly);
108 		if (fp != NULL) {
109 			(void)fseek(otf, 0L, SEEK_END);
110 			size = ftell(otf);
111 			mp->m_block = blockof(size);
112 			mp->m_offset = offsetof(size);
113 			mp->m_size = fsize(fp);
114 			mp->m_lines = 0;
115 			mp->m_flag |= MODIFY;
116 			rewind(fp);
117 			while ((c = getc(fp)) != EOF) {
118 				if (c == '\n') {
119 					mp->m_lines++;
120 					nl++;
121 				} else
122 					nl = 0;
123 				if (putc(c, otf) == EOF)
124 					break;
125 			}
126 			for (; nl < 2; nl++) {
127 				mp->m_lines++;
128 				mp->m_size++;
129 				putc('\n', otf);
130 			}
131 			if (ferror(otf))
132 				warn("%s", tmpdir);
133 			(void)Fclose(fp);
134 		}
135 		(void)sigprocmask(SIG_SETMASK, &oset, NULL);
136 		(void)sigaction(SIGINT, &oact, NULL);
137 	}
138 	return(0);
139 }
140 
141 /*
142  * Run an editor on the file at "fpp" of "size" bytes,
143  * and return a new file pointer.
144  * Signals must be handled by the caller.
145  * "Type" is 'e' for _PATH_EX, 'v' for _PATH_VI.
146  */
147 FILE *
run_editor(FILE * fp,off_t size,int type,int readonly)148 run_editor(FILE *fp, off_t size, int type, int readonly)
149 {
150 	FILE *nf = NULL;
151 	int t;
152 	time_t modtime;
153 	char *edit, tempname[PATHSIZE];
154 	struct stat statb;
155 
156 	(void)snprintf(tempname, sizeof(tempname),
157 	    "%s/mail.ReXXXXXXXXXX", tmpdir);
158 	if ((t = mkstemp(tempname)) == -1 ||
159 	    (nf = Fdopen(t, "w")) == NULL) {
160 		warn("%s", tempname);
161 		goto out;
162 	}
163 	if (readonly && fchmod(t, 0400) == -1) {
164 		warn("%s", tempname);
165 		(void)rm(tempname);
166 		goto out;
167 	}
168 	if (size >= 0)
169 		while (--size >= 0 && (t = getc(fp)) != EOF)
170 			(void)putc(t, nf);
171 	else
172 		while ((t = getc(fp)) != EOF)
173 			(void)putc(t, nf);
174 	(void)fflush(nf);
175 	if (fstat(fileno(nf), &statb) == -1)
176 		modtime = 0;
177 	else
178 		modtime = statb.st_mtime;
179 	if (ferror(nf)) {
180 		(void)Fclose(nf);
181 		warn("%s", tempname);
182 		(void)rm(tempname);
183 		nf = NULL;
184 		goto out;
185 	}
186 	if (Fclose(nf) < 0) {
187 		warn("%s", tempname);
188 		(void)rm(tempname);
189 		nf = NULL;
190 		goto out;
191 	}
192 	nf = NULL;
193 	if (type == 'e') {
194 		edit = value("EDITOR");
195 		if (edit == NULL || edit[0] == '\0')
196 			edit = _PATH_EX;
197 	} else {
198 		edit = value("VISUAL");
199 		if (edit == NULL || edit[0] == '\0')
200 			edit = _PATH_VI;
201 	}
202 	if (editit(edit, tempname) == -1) {
203 		(void)rm(tempname);
204 		goto out;
205 	}
206 	/*
207 	 * If in read only mode or file unchanged, just remove the editor
208 	 * temporary and return.
209 	 */
210 	if (readonly) {
211 		(void)rm(tempname);
212 		goto out;
213 	}
214 	if (stat(tempname, &statb) == -1) {
215 		warn("%s", tempname);
216 		goto out;
217 	}
218 	if (modtime == statb.st_mtime) {
219 		(void)rm(tempname);
220 		goto out;
221 	}
222 	/*
223 	 * Now switch to new file.
224 	 */
225 	if ((nf = Fopen(tempname, "a+")) == NULL) {
226 		warn("%s", tempname);
227 		(void)rm(tempname);
228 		goto out;
229 	}
230 	(void)rm(tempname);
231 out:
232 	return(nf);
233 }
234 
235 /*
236  * Execute an editor on the specified pathname, which is interpreted
237  * from the shell.  This means flags may be included.
238  *
239  * Returns -1 on error, or the exit value on success.
240  */
241 int
editit(const char * ed,const char * pathname)242 editit(const char *ed, const char *pathname)
243 {
244 	char *argp[] = {"sh", "-c", NULL, NULL}, *p;
245 	sig_t sighup, sigint, sigquit, sigchld;
246 	pid_t pid;
247 	int saved_errno, st, ret = -1;
248 
249 	if (ed == NULL)
250 		ed = getenv("VISUAL");
251 	if (ed == NULL || ed[0] == '\0')
252 		ed = getenv("EDITOR");
253 	if (ed == NULL || ed[0] == '\0')
254 		ed = _PATH_VI;
255 	if (asprintf(&p, "%s %s", ed, pathname) == -1)
256 		return (-1);
257 	argp[2] = p;
258 
259 	sighup = signal(SIGHUP, SIG_IGN);
260 	sigint = signal(SIGINT, SIG_IGN);
261 	sigquit = signal(SIGQUIT, SIG_IGN);
262 	sigchld = signal(SIGCHLD, SIG_DFL);
263 	if ((pid = fork()) == -1)
264 		goto fail;
265 	if (pid == 0) {
266 		execv(_PATH_BSHELL, argp);
267 		_exit(127);
268 	}
269 	while (waitpid(pid, &st, 0) == -1)
270 		if (errno != EINTR)
271 			goto fail;
272 	if (!WIFEXITED(st))
273 		errno = EINTR;
274 	else
275 		ret = WEXITSTATUS(st);
276 
277  fail:
278 	saved_errno = errno;
279 	(void)signal(SIGHUP, sighup);
280 	(void)signal(SIGINT, sigint);
281 	(void)signal(SIGQUIT, sigquit);
282 	(void)signal(SIGCHLD, sigchld);
283 	free(p);
284 	errno = saved_errno;
285 	return (ret);
286 }
287