log_read.h revision 3cb54987857690fa5b73f0192cc052eb55b562f7 
1/*
2 * Copyright (C) 2013-2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef _LIBS_LOG_LOG_READ_H
18#define _LIBS_LOG_LOG_READ_H
19
20#include <stdint.h>
21#include <time.h>
22
23/* struct log_time is a wire-format variant of struct timespec */
24#define NS_PER_SEC 1000000000ULL
25
26#ifdef __cplusplus
27
28// NB: do NOT define a copy constructor. This will result in structure
29// no longer being compatible with pass-by-value which is desired
30// efficient behavior. Also, pass-by-reference breaks C/C++ ABI.
31struct log_time {
32public:
33    uint32_t tv_sec; // good to Feb 5 2106
34    uint32_t tv_nsec;
35
36    static const uint32_t tv_sec_max = 0xFFFFFFFFUL;
37    static const uint32_t tv_nsec_max = 999999999UL;
38
39    log_time(const timespec &T)
40    {
41        tv_sec = T.tv_sec;
42        tv_nsec = T.tv_nsec;
43    }
44    log_time(uint32_t sec, uint32_t nsec)
45    {
46        tv_sec = sec;
47        tv_nsec = nsec;
48    }
49    static const timespec EPOCH;
50    log_time()
51    {
52    }
53    log_time(clockid_t id)
54    {
55        timespec T;
56        clock_gettime(id, &T);
57        tv_sec = T.tv_sec;
58        tv_nsec = T.tv_nsec;
59    }
60    log_time(const char *T)
61    {
62        const uint8_t *c = (const uint8_t *) T;
63        tv_sec = c[0] | (c[1] << 8) | (c[2] << 16) | (c[3] << 24);
64        tv_nsec = c[4] | (c[5] << 8) | (c[6] << 16) | (c[7] << 24);
65    }
66
67    // timespec
68    bool operator== (const timespec &T) const
69    {
70        return (tv_sec == T.tv_sec) && (tv_nsec == T.tv_nsec);
71    }
72    bool operator!= (const timespec &T) const
73    {
74        return !(*this == T);
75    }
76    bool operator< (const timespec &T) const
77    {
78        return (tv_sec < T.tv_sec)
79            || ((tv_sec == T.tv_sec) && (tv_nsec < T.tv_nsec));
80    }
81    bool operator>= (const timespec &T) const
82    {
83        return !(*this < T);
84    }
85    bool operator> (const timespec &T) const
86    {
87        return (tv_sec > T.tv_sec)
88            || ((tv_sec == T.tv_sec) && (tv_nsec > T.tv_nsec));
89    }
90    bool operator<= (const timespec &T) const
91    {
92        return !(*this > T);
93    }
94    log_time operator-= (const timespec &T);
95    log_time operator- (const timespec &T) const
96    {
97        log_time local(*this);
98        return local -= T;
99    }
100
101    // log_time
102    bool operator== (const log_time &T) const
103    {
104        return (tv_sec == T.tv_sec) && (tv_nsec == T.tv_nsec);
105    }
106    bool operator!= (const log_time &T) const
107    {
108        return !(*this == T);
109    }
110    bool operator< (const log_time &T) const
111    {
112        return (tv_sec < T.tv_sec)
113            || ((tv_sec == T.tv_sec) && (tv_nsec < T.tv_nsec));
114    }
115    bool operator>= (const log_time &T) const
116    {
117        return !(*this < T);
118    }
119    bool operator> (const log_time &T) const
120    {
121        return (tv_sec > T.tv_sec)
122            || ((tv_sec == T.tv_sec) && (tv_nsec > T.tv_nsec));
123    }
124    bool operator<= (const log_time &T) const
125    {
126        return !(*this > T);
127    }
128    log_time operator-= (const log_time &T);
129    log_time operator- (const log_time &T) const
130    {
131        log_time local(*this);
132        return local -= T;
133    }
134
135    uint64_t nsec() const
136    {
137        return static_cast<uint64_t>(tv_sec) * NS_PER_SEC + tv_nsec;
138    }
139
140    static const char default_format[];
141
142    // Add %#q for the fraction of a second to the standard library functions
143    char *strptime(const char *s, const char *format = default_format);
144} __attribute__((__packed__));
145
146#else
147
148typedef struct log_time {
149    uint32_t tv_sec;
150    uint32_t tv_nsec;
151} __attribute__((__packed__)) log_time;
152
153#endif
154
155#endif /* define _LIBS_LOG_LOG_READ_H */
156