1/*****************************************************************************/
2/* */
3/* filestat.c */
4/* */
5/* Replacement for Windows code */
6/* */
7/* */
8/* */
9/* (C) 2012, Ullrich von Bassewitz */
10/* Roemerstrasse 52 */
11/* D-70794 Filderstadt */
12/* EMail: uz@cc65.org */
13/* */
14/* */
15/* This software is provided 'as-is', without any expressed or implied */
16/* warranty. In no event will the authors be held liable for any damages */
17/* arising from the use of this software. */
18/* */
19/* Permission is granted to anyone to use this software for any purpose, */
20/* including commercial applications, and to alter it and redistribute it */
21/* freely, subject to the following restrictions: */
22/* */
23/* 1. The origin of this software must not be misrepresented; you must not */
24/* claim that you wrote the original software. If you use this software */
25/* in a product, an acknowledgment in the product documentation would be */
26/* appreciated but is not required. */
27/* 2. Altered source versions must be plainly marked as such, and must not */
28/* be misrepresented as being the original software. */
29/* 3. This notice may not be removed or altered from any source */
30/* distribution. */
31/* */
32/*****************************************************************************/
33
34
35
36/* This module works around bugs in the time conversion code supplied by
37** Microsoft. See here for a description of the problem:
38** http://www.codeproject.com/KB/datetime/dstbugs.aspx
39** Please let me note that I find it absolutely unacceptable to just declare
40** buggy behaviour like this "works as designed" as Microsoft does. The
41** problems did even make it into .NET, where the DateTime builtin data type
42** has exactly the same problems as described in the article above.
43*/
44
45
46
47#include <sys/types.h>
48#include <sys/stat.h>
49#if defined(_WIN32)
50# include <errno.h>
51# include <windows.h>
52#endif
53
54/* common */
55#include "filestat.h"
56
57
58
59/*****************************************************************************/
60/* Code */
61/*****************************************************************************/
62
63
64
65#if defined(_WIN32)
66
67
68
69static time_t FileTimeToUnixTime (const FILETIME* T)
70/* Calculate a unix time_t value from a FILETIME. FILETIME contains a 64 bit
71** value with point zero at 1600-01-01 00:00:00 and counting 100ns intervals.
72** time_t is in seconds since 1970-01-01 00:00:00.
73*/
74{
75 /* Offset between 1600-01-01 and the Epoch in seconds. Watcom C has no
76 ** way to express a number > 32 bit (known to me) but is able to do
77 ** calculations with 64 bit integers, so we need to do it this way.
78 */
79 static const ULARGE_INTEGER Offs = { { 0xB6109100UL, 0x00000020UL } };
80 ULARGE_INTEGER V;
81 V.LowPart = T->dwLowDateTime;
82 V.HighPart = T->dwHighDateTime;
83 return (V.QuadPart / 10000000U) - Offs.QuadPart;
84}
85
86
87
88int FileStat (const char* Path, struct stat* Buf)
89/* Replacement function for stat() */
90{
91
92 HANDLE H;
93 BY_HANDLE_FILE_INFORMATION Info;
94
95 /* First call stat() */
96 int Error = stat (Path, Buf);
97 if (Error != 0) {
98 return Error;
99 }
100
101 /* Open the file using backup semantics, so we won't change atime. Then
102 ** retrieve the correct times in UTC and replace the ones in Buf. Return
103 ** EACCES in case of errors to avoid the hassle of translating windows
104 ** error codes to standard ones.
105 */
106 H = CreateFile (Path,
107 GENERIC_READ,
108 FILE_SHARE_READ,
109 0, /* Security attributes */
110 OPEN_EXISTING,
111 FILE_FLAG_BACKUP_SEMANTICS,
112 0); /* Template file */
113 if (H != INVALID_HANDLE_VALUE) {
114 if (GetFileInformationByHandle (H, &Info)) {
115 Buf->st_ctime = FileTimeToUnixTime (&Info.ftCreationTime);
116 Buf->st_atime = FileTimeToUnixTime (&Info.ftLastAccessTime);
117 Buf->st_mtime = FileTimeToUnixTime (&Info.ftLastWriteTime);
118 } else {
119 Error = EACCES;
120 }
121 (void) CloseHandle (H);
122 } else {
123 Error = EACCES;
124 }
125
126 /* Done */
127 return Error;
128}
129
130
131
132#else
133
134
135
136int FileStat (const char* Path, struct stat* Buf)
137/* Replacement function for stat() */
138{
139 /* Just call the function which works without errors */
140 return stat (Path, Buf);
141}
142
143
144
145#endif
146