1 /*
2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2021, Dave Pare, Jeff Bailey, Thomas Ruschak,
4 * Ken Stevens, Steve McClure, Markus Armbruster
5 *
6 * Empire is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 *
19 * ---
20 *
21 * See files README, COPYING and CREDITS in the root of the source
22 * tree for related information and legal notices. It is expected
23 * that future projects/authors will amend these files as needed.
24 *
25 * ---
26 *
27 * log.c: Log an Empire error to a file
28 *
29 * Known contributors to this file:
30 * Dave Pare, 1989
31 * Markus Armbruster, 2003-2010
32 */
33
34 #include <config.h>
35
36 #include <errno.h>
37 #include <fcntl.h>
38 #include <stdarg.h>
39 #include <stdio.h>
40 #include <sys/stat.h>
41 #include <time.h>
42 #include <unistd.h>
43 #include "misc.h"
44 #include "prototypes.h"
45
46 void (*oops_handler)(void) = abort;
47
48 static char logfile[32];
49 static int logfd = -1;
50
51 static int logopen(void);
52
53 /*
54 * Points log file at @program.log
55 */
56 int
loginit(char * program)57 loginit(char *program)
58 {
59 sprintf(logfile, "%.*s.log", (int)sizeof(logfile) - 5, program);
60 logfd = logopen();
61 return logfd;
62 }
63
64 static int
logopen(void)65 logopen(void)
66 {
67 int fd;
68
69 fd = open(logfile, O_WRONLY | O_CREAT | O_APPEND,
70 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
71 if (fd < 0)
72 logerror("Can't open %s (%s)", logfile, strerror(errno));
73 return fd;
74 }
75
76 int
logreopen(void)77 logreopen(void)
78 {
79 int newfd, res;
80
81 if ((newfd = logopen()) < 0)
82 return -1;
83 res = close(logfd);
84 logfd = newfd;
85 if (res < 0)
86 logerror("Can't close %s (%s)", logfile, strerror(errno));
87 return res;
88 }
89
90 /*
91 * Write a line to the log file and to stderr.
92 * Messages are silently truncated after 512 characters or a newline.
93 */
94 void
logerror(char * format,...)95 logerror(char *format, ...)
96 {
97 enum {
98 ctime_len = 24, /* output of ctime() less the newline */
99 msg_space = 512 /* space for formatted message */
100 };
101 va_list list;
102 time_t now;
103 char buf[ctime_len + 1 + msg_space + 2];
104 char *msg, *p;
105
106 va_start(list, format);
107 msg = buf + ctime_len + 1;
108 vsnprintf(msg, msg_space, format, list);
109 buf[sizeof(buf)-2] = 0;
110 p = msg + strlen(msg);
111 p[0] = '\n';
112 p[1] = 0;
113 p = strchr(msg, '\n');
114 p[1] = 0;
115 fputs(msg, stderr);
116 if (logfd >= 0) {
117 time(&now);
118 memcpy(buf, ctime(&now), ctime_len);
119 buf[ctime_len] = ' ';
120 write(logfd, buf, strlen(buf));
121 }
122 va_end(list);
123 }
124
125 /*
126 * Log internal error @msg occured in @file:@line, call oops handler.
127 */
128 void
oops(char * msg,char * file,int line)129 oops(char *msg, char *file, int line)
130 {
131 logerror("Oops: %s in %s:%d", msg ? msg : "bug", file, line);
132 oops_handler();
133 }
134
135 /*
136 * Report out-of-memory condition and terminate the program.
137 * Use this with restraint! Clean error recovery is preferable, but
138 * not always feasible (e.g. halfway through the update) or worthwhile
139 * (during server startup).
140 */
141 void
exit_nomem(void)142 exit_nomem(void)
143 {
144 logerror("Memory exhausted");
145 exit(1);
146 }
147