1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
|
/* $OpenBSD: edit.c,v 1.8 2005/12/27 05:00:28 deraadt Exp $ */
/*
* Written by Raymond Lai <ray@cyth.net>.
* Public domain.
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <ctype.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "extern.h"
__dead static void cleanup(const char *);
static void edit(const char *);
static char *xmktemp(const char *);
static void
cleanup(const char *filename)
{
if (unlink(filename))
err(2, "could not delete: %s", filename);
exit(2);
}
/*
* Takes the name of a file and opens it with an editor.
*/
static void
edit(const char *filename)
{
int status;
pid_t pid;
const char *editor;
editor = getenv("VISUAL");
if (editor == NULL)
editor = getenv("EDITOR");
if (editor == NULL)
editor = "vi";
/* Start editor on temporary file. */
switch (pid = fork()) {
case 0:
/* child */
execlp(editor, editor, filename, (void *)NULL);
warn("could not execute editor: %s", editor);
cleanup(filename);
/* NOTREACHED */
case -1:
warn("could not fork");
cleanup(filename);
/* NOTREACHED */
}
/* parent */
/* Wait for editor to exit. */
if (waitpid(pid, &status, 0) == -1) {
warn("waitpid");
cleanup(filename);
/* NOTREACHED */
}
/* Check that editor terminated normally. */
if (!WIFEXITED(status)) {
warn("%s terminated abnormally", editor);
cleanup(filename);
/* NOTREACHED */
}
}
/*
* Creates and returns the name of a temporary file. Takes a string
* (or NULL) is written to the temporary file. The returned string
* needs to be freed.
*/
static char *
xmktemp(const char *s)
{
FILE *file;
int fd;
const char *tmpdir;
char *filename;
/* If TMPDIR is set, use it; otherwise use /tmp. */
if (!(tmpdir = getenv("TMPDIR")))
tmpdir = "/tmp";
if (asprintf(&filename, "%s/sdiff.XXXXXXXXXX", tmpdir) == -1)
err(2, "xmktemp");
/* Create temp file. */
if ((fd = mkstemp(filename)) == -1)
err(2, "could not create temporary file");
/* If we don't write anything to the file, just close. */
if (s == NULL) {
close(fd);
return (filename);
}
/* Open temp file for writing. */
if ((file = fdopen(fd, "w")) == NULL) {
warn("could not open %s", filename);
cleanup(filename);
/* NOTREACHED */
}
/* Write to file. */
if (fputs(s, file)) {
warn("could not write to %s", filename);
cleanup(filename);
/* NOTREACHED */
}
/* Close temp file. */
fclose(file);
return (filename);
}
/*
* Parse edit command. Returns 0 on success, -1 on error.
*/
int
eparse(const char *cmd, const char *left, const char *right)
{
FILE *file;
size_t nread, nwritten;
const char *filename;
char buf[BUFSIZ], *text;
/* Skip whitespace. */
while (isspace(*cmd))
++cmd;
text = NULL;
switch (*cmd) {
case '\0':
/* Edit empty file. */
break;
case 'b':
/* Both strings. */
if (left == NULL)
goto RIGHT;
if (right == NULL)
goto LEFT;
/* Neither column is blank, so print both. */
if (asprintf(&text, "%s%s\n", left, right) == -1)
err(2, "could not allocate memory");
break;
case 'l':
LEFT:
/* Skip if there is no left column. */
if (left == NULL)
break;
if (asprintf(&text, "%s\n", left) == -1)
err(2, "could not allocate memory");
break;
case 'r':
RIGHT:
/* Skip if there is no right column. */
if (right == NULL)
break;
if (asprintf(&text, "%s\n", right) == -1)
err(2, "could not allocate memory");
break;
default:
return (-1);
}
/* Create temp file. */
filename = xmktemp(text);
/* text is no longer used. */
free(text);
/* Edit temp file. */
edit(filename);
/* Open temporary file. */
if (!(file = fopen(filename, "r"))) {
warn("could not open edited file: %s", filename);
cleanup(filename);
/* NOTREACHED */
}
/* Copy temporary file contents to output file. */
for (nread = sizeof(buf); nread == sizeof(buf);) {
nread = fread(buf, sizeof(*buf), sizeof(buf), file);
/* Test for error or end of file. */
if (nread != sizeof(buf) &&
(ferror(file) || !feof(file))) {
warnx("error reading edited file: %s", filename);
cleanup(filename);
/* NOTREACHED */
}
/*
* If we have nothing to read, break out of loop
* instead of writing nothing.
*/
if (!nread)
break;
/* Write data we just read. */
nwritten = fwrite(buf, sizeof(*buf), nread, outfile);
if (nwritten != nread) {
warnx("error writing to output file");
cleanup(filename);
/* NOTREACHED */
}
}
/* We've reached the end of the temporary file, so remove it. */
if (unlink(filename))
warn("could not delete: %s", filename);
fclose(file);
/* filename was malloc()ed in xmktemp(). */
free((void *)filename);
return (0);
}
|