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
|
/*
Copyright (C) 2014- The University of Notre Dame
This software is distributed under the GNU General Public License.
See the file COPYING for details.
*/
#include "catch.h"
#include "debug.h"
#include "full_io.h"
#include "stringtools.h"
#include "path.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef PATH_MAX
#define PATH_MAX 1024
#endif
static int file_fd = -1;
static struct stat file_stat;
static char file_path[PATH_MAX];
/* Default size of 0 will not roll over debug info. */
static off_t file_size_max = 0;
/* define custom debug for catch */
#undef debug
#define debug(l,fmt,...) fprintf(stderr, "%s: " fmt "\n", #l, __VA_ARGS__);
int debug_file_reopen (void)
{
int rc;
if (strlen(file_path)) {
int flags;
close(file_fd);
CATCHUNIX(file_fd = open(file_path, O_CREAT|O_APPEND|O_WRONLY|O_NOCTTY, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP));
CATCHUNIX(flags = fcntl(file_fd, F_GETFD));
flags |= FD_CLOEXEC;
CATCHUNIX(fcntl(file_fd, F_SETFD, flags));
CATCHUNIX(fstat(file_fd, &file_stat)); /* save inode */
/* canonicalize the debug_file path for future operations */
{
char tmp[PATH_MAX] = "";
CATCHUNIX(realpath(file_path, tmp) == NULL ? -1 : 0);
memcpy(file_path, tmp, sizeof(file_path));
}
}
rc = 0;
goto out;
out:
return RCUNIX(rc);
}
void debug_file_write (INT64_T flags, const char *str)
{
int rc;
/* Beware this code is racey and debug messages may be lost during
* rotations. Two processes rotating logs at the same time may create two
* new logs. The stat on the filename and inode comparison catches this
* after one lost debug message.
*/
if (file_size_max > 0) {
struct stat info;
rc = stat(file_path, &info);
if (rc == 0) {
if (info.st_size >= file_size_max) {
char old[PATH_MAX];
string_nformat(old, sizeof(old), "%s.old", file_path);
rename(file_path, old);
debug_file_reopen();
} else if (info.st_ino != file_stat.st_ino) {
/* another process rotated the log */
debug_file_reopen();
}
} else {
fprintf(stderr, "couldn't stat debug file: %s\n", strerror(errno));
abort();
}
}
rc = full_write(file_fd, str, strlen(str));
if (rc == -1) {
fprintf(stderr, "couldn't write to debug file: %s\n", strerror(errno));
abort();
}
}
int debug_file_path (const char *path)
{
strncpy(file_path, path, sizeof(file_path)-1);
return debug_file_reopen();
}
void debug_file_size (off_t size)
{
file_size_max = size;
}
void debug_file_rename (const char *suffix)
{
if (strlen(file_path)) {
char old[PATH_MAX] = "";
string_nformat(old, sizeof(old), "%s.%s", file_path, suffix);
rename(file_path, old);
debug_file_reopen();
}
}
/* vim: set noexpandtab tabstop=4: */
|