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comparison src/timeconv.c @ 182:b65e8d0a088a

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more cleanup on external names in the shared object file
author Carl Byington <carl@five-ten-sg.com>
date Mon, 13 Apr 2009 11:39:33 -0700
parents 6954d315aaa8
children 7c60d6d1c681
comparison
equal deleted inserted replaced
181:3b04745ff76d 182:b65e8d0a088a
1 /***********************************************************************
2 *
3 * Borrowed from WINE sources!! (http://www.winehq.com)
4 * Converts a Win32 FILETIME structure to a UNIX time_t value
5 */
6
7 /*** WARNING ****
8 * This file is not to be included in a Visual C++ Project
9 * It will make the whole project fail to compile
10 * There are functions in libpst.c to handle the dates
11 * Do not use this one
12 */
13
14 #ifndef _WIN32
15
16 #include "define.h" 1 #include "define.h"
17 2
18 char * pst_fileTimeToAscii (const FILETIME *filetime) {
19 time_t t1;
20 3
21 t1 = pst_fileTimeToUnixTime(filetime, NULL); 4
22 return ctime(&t1); 5 char * pst_fileTimeToAscii(const FILETIME* filetime) {
6 time_t t;
7 t = pst_fileTimeToUnixTime(filetime);
8 return ctime(&t);
23 } 9 }
10
24 11
25 struct tm * pst_fileTimeToStructTM (const FILETIME *filetime) { 12 struct tm * pst_fileTimeToStructTM (const FILETIME *filetime) {
26 time_t t1; 13 time_t t1;
27 t1 = pst_fileTimeToUnixTime(filetime, NULL); 14 t1 = pst_fileTimeToUnixTime(filetime);
28 return gmtime(&t1); 15 return gmtime(&t1);
29 } 16 }
30 17
31 /*********************************************************************** 18
32 * DOSFS_FileTimeToUnixTime 19 time_t pst_fileTimeToUnixTime(const FILETIME *filetime)
33 *
34 * Convert a FILETIME format to Unix time.
35 * If not NULL, 'remainder' contains the fractional part of the filetime,
36 * in the range of [0..9999999] (even if time_t is negative).
37 */
38 time_t pst_fileTimeToUnixTime( const FILETIME *filetime, DWORD *remainder )
39 { 20 {
40 /* Read the comment in the function DOSFS_UnixTimeToFileTime. */ 21 int64_t t = filetime->dwHighDateTime;
41 #if USE_LONG_LONG
42
43 long long int t = filetime->dwHighDateTime;
44 t <<= 32; 22 t <<= 32;
45 t += (UINT32)filetime->dwLowDateTime; 23 t += filetime->dwLowDateTime;
46 t -= 116444736000000000LL; 24 t -= 116444736000000000LL;
47 if (t < 0) 25 if (t < 0) {
48 { 26 return -1 - ((-t - 1) / 10000000);
49 if (remainder) *remainder = 9999999 - (-t - 1) % 10000000;
50 return -1 - ((-t - 1) / 10000000);
51 } 27 }
52 else 28 else {
53 { 29 return t / 10000000;
54 if (remainder) *remainder = t % 10000000;
55 return t / 10000000;
56 } 30 }
57
58 #else /* ISO version */
59
60 UINT32 a0; /* 16 bit, low bits */
61 UINT32 a1; /* 16 bit, medium bits */
62 UINT32 a2; /* 32 bit, high bits */
63 UINT32 r; /* remainder of division */
64 unsigned int carry; /* carry bit for subtraction */
65 int negative; /* whether a represents a negative value */
66
67 /* Copy the time values to a2/a1/a0 */
68 a2 = (UINT32)filetime->dwHighDateTime;
69 a1 = ((UINT32)filetime->dwLowDateTime ) >> 16;
70 a0 = ((UINT32)filetime->dwLowDateTime ) & 0xffff;
71
72 /* Subtract the time difference */
73 if (a0 >= 32768 ) a0 -= 32768 , carry = 0;
74 else a0 += (1 << 16) - 32768 , carry = 1;
75
76 if (a1 >= 54590 + carry) a1 -= 54590 + carry, carry = 0;
77 else a1 += (1 << 16) - 54590 - carry, carry = 1;
78
79 a2 -= 27111902 + carry;
80
81 /* If a is negative, replace a by (-1-a) */
82 negative = (a2 >= ((UINT32)1) << 31);
83 if (negative)
84 {
85 /* Set a to -a - 1 (a is a2/a1/a0) */
86 a0 = 0xffff - a0;
87 a1 = 0xffff - a1;
88 a2 = ~a2;
89 }
90
91 /* Divide a by 10000000 (a = a2/a1/a0), put the rest into r.
92 Split the divisor into 10000 * 1000 which are both less than 0xffff. */
93 a1 += (a2 % 10000) << 16;
94 a2 /= 10000;
95 a0 += (a1 % 10000) << 16;
96 a1 /= 10000;
97 r = a0 % 10000;
98 a0 /= 10000;
99
100 a1 += (a2 % 1000) << 16;
101 a2 /= 1000;
102 a0 += (a1 % 1000) << 16;
103 a1 /= 1000;
104 r += (a0 % 1000) * 10000;
105 a0 /= 1000;
106
107 /* If a was negative, replace a by (-1-a) and r by (9999999 - r) */
108 if (negative)
109 {
110 /* Set a to -a - 1 (a is a2/a1/a0) */
111 a0 = 0xffff - a0;
112 a1 = 0xffff - a1;
113 a2 = ~a2;
114
115 r = 9999999 - r;
116 }
117
118 if (remainder) *remainder = r;
119
120 /* Do not replace this by << 32, it gives a compiler warning and it does
121 not work. */
122 return ((((time_t)a2) << 16) << 16) + (a1 << 16) + a0;
123 #endif
124 } 31 }
125 32
126 #endif /* !_WIN32 */