GDAL

cpl_vsi_virtual.h
1 /******************************************************************************
2 * $Id$
3 *
4 * Project: VSI Virtual File System
5 * Purpose: Declarations for classes related to the virtual filesystem.
6 * These would only be normally required by applications implementing
7 * their own virtual file system classes which should be rare.
8 * The class interface may be fragile through versions.
9 * Author: Frank Warmerdam, warmerdam@pobox.com
10 *
11 ******************************************************************************
12 * Copyright (c) 2005, Frank Warmerdam <warmerdam@pobox.com>
13 * Copyright (c) 2010-2014, Even Rouault <even dot rouault at spatialys.com>
14 *
15 * Permission is hereby granted, free of charge, to any person obtaining a
16 * copy of this software and associated documentation files (the "Software"),
17 * to deal in the Software without restriction, including without limitation
18 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
19 * and/or sell copies of the Software, and to permit persons to whom the
20 * Software is furnished to do so, subject to the following conditions:
21 *
22 * The above copyright notice and this permission notice shall be included
23 * in all copies or substantial portions of the Software.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
26 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
28 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
29 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
30 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
31 * DEALINGS IN THE SOFTWARE.
32 ****************************************************************************/
33
34 #ifndef CPL_VSI_VIRTUAL_H_INCLUDED
35 #define CPL_VSI_VIRTUAL_H_INCLUDED
36
37 #include "cpl_vsi.h"
38 #include "cpl_vsi_error.h"
39 #include "cpl_string.h"
40 #include "cpl_multiproc.h"
41
42 #include <map>
43 #include <vector>
44 #include <string>
45
46 // To avoid aliasing to GetDiskFreeSpace to GetDiskFreeSpaceA on Windows
47 #ifdef GetDiskFreeSpace
48 #undef GetDiskFreeSpace
49 #endif
50
51 /************************************************************************/
52 /* VSIVirtualHandle */
53 /************************************************************************/
54
56 class CPL_DLL VSIVirtualHandle {
57 public:
58 virtual int Seek( vsi_l_offset nOffset, int nWhence ) = 0;
59 virtual vsi_l_offset Tell() = 0;
60 virtual size_t Read( void *pBuffer, size_t nSize, size_t nCount ) = 0;
61 virtual int ReadMultiRange( int nRanges, void ** ppData,
62 const vsi_l_offset* panOffsets,
63 const size_t* panSizes );
64 virtual size_t Write( const void *pBuffer, size_t nSize,size_t nCount)=0;
65 virtual int Eof() = 0;
66 virtual int Flush() {return 0;}
67 virtual int Close() = 0;
68 // Base implementation that only supports file extension.
69 virtual int Truncate( vsi_l_offset nNewSize );
70 virtual void *GetNativeFileDescriptor() { return nullptr; }
71 virtual VSIRangeStatus GetRangeStatus( CPL_UNUSED vsi_l_offset nOffset,
72 CPL_UNUSED vsi_l_offset nLength )
73 { return VSI_RANGE_STATUS_UNKNOWN; }
74
75 virtual ~VSIVirtualHandle() { }
76 };
77
78 /************************************************************************/
79 /* VSIFilesystemHandler */
80 /************************************************************************/
81
82 #ifndef DOXYGEN_SKIP
83 class CPL_DLL VSIFilesystemHandler {
84
85 public:
86
87 virtual ~VSIFilesystemHandler() {}
88
89 VSIVirtualHandle *Open( const char *pszFilename,
90 const char *pszAccess );
91
92 virtual VSIVirtualHandle *Open( const char *pszFilename,
93 const char *pszAccess,
94 bool bSetError,
95 CSLConstList papszOptions ) = 0;
96 virtual int Stat( const char *pszFilename, VSIStatBufL *pStatBuf, int nFlags) = 0;
97 virtual int Unlink( const char *pszFilename )
98 { (void) pszFilename; errno=ENOENT; return -1; }
99 virtual int* UnlinkBatch( CSLConstList papszFiles );
100 virtual int Mkdir( const char *pszDirname, long nMode )
101 {(void)pszDirname; (void)nMode; errno=ENOENT; return -1;}
102 virtual int Rmdir( const char *pszDirname )
103 { (void) pszDirname; errno=ENOENT; return -1; }
104 virtual int RmdirRecursive( const char *pszDirname );
105 virtual char **ReadDir( const char *pszDirname )
106 { (void) pszDirname; return nullptr; }
107 virtual char **ReadDirEx( const char *pszDirname, int /* nMaxFiles */ )
108 { return ReadDir(pszDirname); }
109 virtual char **SiblingFiles( const char * /*pszFilename*/ )
110 { return nullptr; }
111 virtual int Rename( const char *oldpath, const char *newpath )
112 { (void) oldpath; (void)newpath; errno=ENOENT; return -1; }
113 virtual int IsCaseSensitive( const char* pszFilename )
114 { (void) pszFilename; return TRUE; }
115 virtual GIntBig GetDiskFreeSpace( const char* /* pszDirname */ ) { return -1; }
116 virtual int SupportsSparseFiles( const char* /* pszPath */ ) { return FALSE; }
117 virtual int HasOptimizedReadMultiRange(const char* /* pszPath */) { return FALSE; }
118 virtual const char* GetActualURL(const char* /*pszFilename*/) { return nullptr; }
119 virtual const char* GetOptions() { return nullptr; }
120 virtual char* GetSignedURL(const char* /*pszFilename*/, CSLConstList /* papszOptions */) { return nullptr; }
121 virtual bool Sync( const char* pszSource, const char* pszTarget,
122 const char* const * papszOptions,
123 GDALProgressFunc pProgressFunc,
124 void *pProgressData,
125 char*** ppapszOutputs );
126
127 virtual VSIDIR* OpenDir( const char *pszPath, int nRecurseDepth,
128 const char* const *papszOptions);
129
130 virtual char** GetFileMetadata( const char * pszFilename, const char* pszDomain,
131 CSLConstList papszOptions );
132
133 virtual bool SetFileMetadata( const char * pszFilename,
134 CSLConstList papszMetadata,
135 const char* pszDomain,
136 CSLConstList papszOptions );
137
138 virtual bool AbortPendingUploads(const char* /*pszFilename*/) { return true;}
139
140 virtual std::string GetStreamingFilename(const std::string& osFilename) const { return osFilename; }
141 };
142 #endif /* #ifndef DOXYGEN_SKIP */
143
144 /************************************************************************/
145 /* VSIFileManager */
146 /************************************************************************/
147
148 #ifndef DOXYGEN_SKIP
149 class CPL_DLL VSIFileManager
150 {
151 private:
152 VSIFilesystemHandler *poDefaultHandler = nullptr;
153 std::map<std::string, VSIFilesystemHandler *> oHandlers{};
154
155 VSIFileManager();
156
157 static VSIFileManager *Get();
158
159 CPL_DISALLOW_COPY_ASSIGN(VSIFileManager)
160
161 public:
162 ~VSIFileManager();
163
164 static VSIFilesystemHandler *GetHandler( const char * );
165 static void InstallHandler( const std::string& osPrefix,
166 VSIFilesystemHandler * );
167 /* RemoveHandler is never defined. */
168 /* static void RemoveHandler( const std::string& osPrefix ); */
169
170 static char** GetPrefixes();
171 };
172 #endif /* #ifndef DOXYGEN_SKIP */
173
174 /************************************************************************/
175 /* ==================================================================== */
176 /* VSIArchiveFilesystemHandler */
177 /* ==================================================================== */
178 /************************************************************************/
179
180 #ifndef DOXYGEN_SKIP
181
182 class VSIArchiveEntryFileOffset
183 {
184 public:
185 virtual ~VSIArchiveEntryFileOffset();
186 };
187
188 typedef struct
189 {
190 char *fileName;
191 vsi_l_offset uncompressed_size;
192 VSIArchiveEntryFileOffset* file_pos;
193 int bIsDir;
194 GIntBig nModifiedTime;
195 } VSIArchiveEntry;
196
197 class VSIArchiveContent
198 {
199 public:
200 time_t mTime = 0;
201 vsi_l_offset nFileSize = 0;
202 int nEntries = 0;
203 VSIArchiveEntry* entries = nullptr;
204
205 ~VSIArchiveContent();
206 };
207
208 class VSIArchiveReader
209 {
210 public:
211 virtual ~VSIArchiveReader();
212
213 virtual int GotoFirstFile() = 0;
214 virtual int GotoNextFile() = 0;
215 virtual VSIArchiveEntryFileOffset* GetFileOffset() = 0;
216 virtual GUIntBig GetFileSize() = 0;
217 virtual CPLString GetFileName() = 0;
218 virtual GIntBig GetModifiedTime() = 0;
219 virtual int GotoFileOffset(VSIArchiveEntryFileOffset* pOffset) = 0;
220 };
221
222 class VSIArchiveFilesystemHandler : public VSIFilesystemHandler
223 {
224 CPL_DISALLOW_COPY_ASSIGN(VSIArchiveFilesystemHandler)
225
226 protected:
227 CPLMutex* hMutex = nullptr;
228 /* We use a cache that contains the list of files contained in a VSIArchive file as */
229 /* unarchive.c is quite inefficient in listing them. This speeds up access to VSIArchive files */
230 /* containing ~1000 files like a CADRG product */
231 std::map<CPLString,VSIArchiveContent*> oFileList{};
232
233 virtual const char* GetPrefix() = 0;
234 virtual std::vector<CPLString> GetExtensions() = 0;
235 virtual VSIArchiveReader* CreateReader(const char* pszArchiveFileName) = 0;
236
237 public:
238 VSIArchiveFilesystemHandler();
239 virtual ~VSIArchiveFilesystemHandler();
240
241 int Stat( const char *pszFilename, VSIStatBufL *pStatBuf,
242 int nFlags ) override;
243 int Unlink( const char *pszFilename ) override;
244 int Rename( const char *oldpath, const char *newpath ) override;
245 int Mkdir( const char *pszDirname, long nMode ) override;
246 int Rmdir( const char *pszDirname ) override;
247 char **ReadDirEx( const char *pszDirname, int nMaxFiles ) override;
248
249 virtual const VSIArchiveContent* GetContentOfArchive(const char* archiveFilename, VSIArchiveReader* poReader = nullptr);
250 virtual char* SplitFilename(const char *pszFilename, CPLString &osFileInArchive, int bCheckMainFileExists);
251 virtual VSIArchiveReader* OpenArchiveFile(const char* archiveFilename, const char* fileInArchiveName);
252 virtual int FindFileInArchive(const char* archiveFilename, const char* fileInArchiveName, const VSIArchiveEntry** archiveEntry);
253 };
254
255 /************************************************************************/
256 /* VSIDIR */
257 /************************************************************************/
258
259 struct CPL_DLL VSIDIR
260 {
261 VSIDIR() = default;
262 virtual ~VSIDIR();
263
264 virtual const VSIDIREntry* NextDirEntry() = 0;
265
266 private:
267 VSIDIR(const VSIDIR&) = delete;
268 VSIDIR& operator=(const VSIDIR&) = delete;
269 };
270
271 #endif /* #ifndef DOXYGEN_SKIP */
272
273 VSIVirtualHandle CPL_DLL *VSICreateBufferedReaderHandle(VSIVirtualHandle* poBaseHandle);
274 VSIVirtualHandle* VSICreateBufferedReaderHandle(VSIVirtualHandle* poBaseHandle,
275 const GByte* pabyBeginningContent,
276 vsi_l_offset nCheatFileSize);
277 VSIVirtualHandle CPL_DLL *VSICreateCachedFile( VSIVirtualHandle* poBaseHandle, size_t nChunkSize = 32768, size_t nCacheSize = 0 );
278
279 const int CPL_DEFLATE_TYPE_GZIP = 0;
280 const int CPL_DEFLATE_TYPE_ZLIB = 1;
281 const int CPL_DEFLATE_TYPE_RAW_DEFLATE = 2;
282 VSIVirtualHandle CPL_DLL *VSICreateGZipWritable( VSIVirtualHandle* poBaseHandle, int nDeflateType, int bAutoCloseBaseHandle );
283
284 VSIVirtualHandle *VSICreateUploadOnCloseFile( VSIVirtualHandle* poBaseHandle );
285
286 #endif /* ndef CPL_VSI_VIRTUAL_H_INCLUDED */
GByte
unsigned char GByte
Unsigned byte type.
Definition: cpl_port.h:203
cpl_vsi.h
VSIRangeStatus
VSIRangeStatus
Range status.
Definition: cpl_vsi.h:176
CPLString
Convenient string class based on std::string.
Definition: cpl_string.h:319
VSI_RANGE_STATUS_UNKNOWN
@ VSI_RANGE_STATUS_UNKNOWN
Unknown.
Definition: cpl_vsi.h:178
CSLConstList
char ** CSLConstList
Type of a constant null-terminated list of nul terminated strings.
Definition: cpl_port.h:1053
GUIntBig
unsigned long long GUIntBig
Large unsigned integer type (generally 64-bit unsigned integer type).
Definition: cpl_port.h:233
VSIDIREntry
Directory entry.
Definition: cpl_vsi.h:340
cpl_string.h
vsi_l_offset
GUIntBig vsi_l_offset
Type for a file offset.
Definition: cpl_vsi.h:140
GIntBig
long long GIntBig
Large signed integer type (generally 64-bit integer type).
Definition: cpl_port.h:230
CPL_UNUSED
#define CPL_UNUSED
Qualifier for an argument that is unused.
Definition: cpl_port.h:875
VSIDIR
struct VSIDIR VSIDIR
Opaque type for a directory iterator.
Definition: cpl_vsi.h:329
VSIStatBufL
#define VSIStatBufL
Type for VSIStatL()
Definition: cpl_vsi.h:198
VSIVirtualHandle
Virtual file handle.
Definition: cpl_vsi_virtual.h:56
CPL_DISALLOW_COPY_ASSIGN
#define CPL_DISALLOW_COPY_ASSIGN(ClassName)
Helper to remove the copy and assignment constructors so that the compiler will not generate the defa...
Definition: cpl_port.h:927