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21
22 // MARKER(update_precomp.py): autogen include statement, do not remove
23 #include "precompiled_desktop.hxx"
24
25 #include "dp_misc.h"
26 #include "dp_persmap.h"
27 #include "rtl/strbuf.hxx"
28
29 using namespace ::rtl;
30
31 // the persistent map is used to manage a handful of key-value string pairs
32 // this implementation replaces a rather heavy-weight berkeleydb integration
33
34 // the file backing up a persistent map consists of line pairs with
35 // - a key string (encoded with chars 0x00..0x0F being escaped)
36 // - a value string (encoded with chars 0x00..0x0F being escaped)
37
38 namespace dp_misc
39 {
40
41 static const char PmapMagic[4] = {'P','m','p','1'};
42
43 //______________________________________________________________________________
PersistentMap(OUString const & url_,bool readOnly)44 PersistentMap::PersistentMap( OUString const & url_, bool readOnly )
45 : m_MapFile( expandUnoRcUrl(url_) )
46 , m_bReadOnly( readOnly)
47 , m_bIsOpen( false)
48 , m_bToBeCreated( !readOnly)
49 , m_bIsDirty( false)
50 {
51 open();
52 }
53
54 //______________________________________________________________________________
PersistentMap()55 PersistentMap::PersistentMap()
56 : m_MapFile( OUString())
57 , m_bReadOnly( false)
58 , m_bIsOpen( false)
59 , m_bToBeCreated( false)
60 , m_bIsDirty( false)
61 {}
62
63 //______________________________________________________________________________
~PersistentMap()64 PersistentMap::~PersistentMap()
65 {
66 if( m_bIsDirty)
67 flush();
68 if( m_bIsOpen)
69 m_MapFile.close();
70 }
71
72 //______________________________________________________________________________
73
74 // replace 0x00..0x0F with "%0".."%F"
75 // replace "%" with "%%"
encodeString(const OString & rStr)76 static OString encodeString( const OString& rStr)
77 {
78 const sal_Char* pChar = rStr.getStr();
79 const sal_Int32 nLen = rStr.getLength();
80 sal_Int32 i = nLen;
81 // short circuit for the simple non-encoded case
82 while( --i >= 0)
83 {
84 const sal_Char c = *(pChar++);
85 if( (0x00 <= c) && (c <= 0x0F))
86 break;
87 if( c == '%')
88 break;
89 }
90 if( i < 0)
91 return rStr;
92
93 // escape chars 0x00..0x0F with "%0".."%F"
94 OStringBuffer aEncStr( nLen + 32);
95 aEncStr.append( pChar - (nLen-i), nLen - i);
96 while( --i >= 0)
97 {
98 sal_Char c = *(pChar++);
99 if( (0x00 <= c) && (c <= 0x0F))
100 {
101 aEncStr.append( '%');
102 c += (c <= 0x09) ? '0' : 'A'-10;
103 } else if( c == '%')
104 aEncStr.append( '%');
105 aEncStr.append( c);
106 }
107
108 return aEncStr.makeStringAndClear();
109 }
110
111 //______________________________________________________________________________
112
113 // replace "%0".."%F" with 0x00..0x0F
114 // replace "%%" with "%"
decodeString(const sal_Char * pEncChars,int nLen)115 static OString decodeString( const sal_Char* pEncChars, int nLen)
116 {
117 const char* pChar = pEncChars;
118 sal_Int32 i = nLen;
119 // short circuit for the simple non-encoded case
120 while( --i >= 0)
121 if( *(pChar++) == '%')
122 break;
123 if( i < 0)
124 return OString( pEncChars, nLen);
125
126 // replace escaped chars with their decoded counterparts
127 OStringBuffer aDecStr( nLen);
128 pChar = pEncChars;
129 for( i = nLen; --i >= 0;)
130 {
131 sal_Char c = *(pChar++);
132 // handle escaped character
133 if( c == '%')
134 {
135 --i;
136 OSL_ASSERT( i >= 0);
137 c = *(pChar++);
138 if( ('0' <= c) && (c <= '9'))
139 c -= '0';
140 else
141 {
142 OSL_ASSERT( ('A' <= c) && (c <= 'F'));
143 c -= ('A'-10);
144 }
145 }
146 aDecStr.append( c);
147 }
148
149 return aDecStr.makeStringAndClear();
150 }
151
152 //______________________________________________________________________________
open()153 bool PersistentMap::open()
154 {
155 // open the existing file
156 sal_uInt32 nOpenFlags = osl_File_OpenFlag_Read;
157 if( !m_bReadOnly)
158 nOpenFlags |= osl_File_OpenFlag_Write;
159
160 const osl::File::RC rcOpen = m_MapFile.open( nOpenFlags);
161 m_bIsOpen = (rcOpen == osl::File::E_None);
162
163 // or create later if needed
164 m_bToBeCreated &= (rcOpen == osl::File::E_NOENT) && !m_bIsOpen;
165
166 if( !m_bIsOpen)
167 return m_bToBeCreated;
168
169 const bool readOK = readAll();
170 return readOK;
171 }
172
173 //______________________________________________________________________________
readAll()174 bool PersistentMap::readAll()
175 {
176 // prepare for re-reading the map-file
177 m_MapFile.setPos( osl_Pos_Absolut, 0);
178 m_entries.clear();
179
180 // read header and check magic
181 char aHeaderBytes[ sizeof(PmapMagic)];
182 sal_uInt64 nBytesRead = 0;
183 m_MapFile.read( aHeaderBytes, sizeof(aHeaderBytes), nBytesRead);
184 OSL_ASSERT( nBytesRead == sizeof(aHeaderBytes));
185 if( nBytesRead != sizeof(aHeaderBytes))
186 return false;
187 // check header magic
188 for( int i = 0; i < (int)sizeof(PmapMagic); ++i)
189 if( aHeaderBytes[i] != PmapMagic[i])
190 return false;
191
192 // read key value pairs and add them to the map
193 ByteSequence aKeyLine;
194 ByteSequence aValLine;
195 for(;;)
196 {
197 // read key-value line pair
198 // an empty key name indicates the end of the line pairs
199 if( m_MapFile.readLine( aKeyLine) != osl::File::E_None)
200 return false;
201 if( !aKeyLine.getLength())
202 break;
203 if( m_MapFile.readLine( aValLine) != osl::File::E_None)
204 return false;
205 // decode key and value strings
206 const OString aKeyName = decodeString( (sal_Char*)aKeyLine.getConstArray(), aKeyLine.getLength());
207 const OString aValName = decodeString( (sal_Char*)aValLine.getConstArray(), aValLine.getLength());
208 // insert key-value pair into map
209 add( aKeyName, aValName);
210 // check end-of-file status
211 sal_Bool bIsEOF = true;
212 if( m_MapFile.isEndOfFile( &bIsEOF) != osl::File::E_None)
213 return false;
214 if( bIsEOF)
215 break;
216 }
217
218 m_bIsDirty = false;
219 return true;
220 }
221
222 //______________________________________________________________________________
flush(void)223 void PersistentMap::flush( void)
224 {
225 if( !m_bIsDirty)
226 return;
227 OSL_ASSERT( !m_bReadOnly);
228 if( m_bToBeCreated && !m_entries.empty())
229 {
230 const sal_uInt32 nOpenFlags = osl_File_OpenFlag_Read | osl_File_OpenFlag_Write | osl_File_OpenFlag_Create;
231 const osl::File::RC rcOpen = m_MapFile.open( nOpenFlags);
232 m_bIsOpen = (rcOpen == osl::File::E_None);
233 m_bToBeCreated = !m_bIsOpen;
234 }
235 if( !m_bIsOpen)
236 return;
237
238 // write header magic
239 m_MapFile.setPos( osl_Pos_Absolut, 0);
240 sal_uInt64 nBytesWritten = 0;
241 m_MapFile.write( PmapMagic, sizeof(PmapMagic), nBytesWritten);
242
243 // write key value pairs
244 t_string2string_map::const_iterator it = m_entries.begin();
245 for(; it != m_entries.end(); ++it) {
246 // write line for key
247 const OString aKeyString = encodeString( (*it).first);
248 const sal_Int32 nKeyLen = aKeyString.getLength();
249 m_MapFile.write( aKeyString.getStr(), nKeyLen, nBytesWritten);
250 OSL_ASSERT( nKeyLen == (sal_Int32)nBytesWritten);
251 m_MapFile.write( "\n", 1, nBytesWritten);
252 // write line for value
253 const OString& rValString = encodeString( (*it).second);
254 const sal_Int32 nValLen = rValString.getLength();
255 m_MapFile.write( rValString.getStr(), nValLen, nBytesWritten);
256 OSL_ASSERT( nValLen == (sal_Int32)nBytesWritten);
257 m_MapFile.write( "\n", 1, nBytesWritten);
258 }
259
260 // write a file delimiter (an empty key-string)
261 m_MapFile.write( "\n", 1, nBytesWritten);
262 // truncate file here
263 sal_uInt64 nNewFileSize;
264 if( m_MapFile.getPos( nNewFileSize) == osl::File::E_None)
265 m_MapFile.setSize( nNewFileSize);
266 // flush to disk
267 m_MapFile.sync();
268 // the in-memory map now matches to the file on disk
269 m_bIsDirty = false;
270 }
271
272 //______________________________________________________________________________
has(OString const & key) const273 bool PersistentMap::has( OString const & key ) const
274 {
275 return get( NULL, key );
276 }
277
278 //______________________________________________________________________________
get(OString * value,OString const & key) const279 bool PersistentMap::get( OString * value, OString const & key ) const
280 {
281 t_string2string_map::const_iterator it = m_entries.find( key);
282 if( it == m_entries.end())
283 return false;
284 if( value)
285 *value = it->second;
286 return true;
287 }
288
289 //______________________________________________________________________________
add(OString const & key,OString const & value)290 void PersistentMap::add( OString const & key, OString const & value )
291 {
292 if( m_bReadOnly)
293 return;
294 typedef std::pair<t_string2string_map::iterator,bool> InsertRC;
295 InsertRC r = m_entries.insert( t_string2string_map::value_type(key,value));
296 m_bIsDirty = r.second;
297 }
298
299 //______________________________________________________________________________
put(OString const & key,OString const & value)300 void PersistentMap::put( OString const & key, OString const & value )
301 {
302 add( key, value);
303 // HACK: flush now as the extension manager does not seem
304 // to properly destruct this object in some situations
305 if( m_bIsDirty)
306 flush();
307 }
308
309 //______________________________________________________________________________
erase(OString const & key,bool flush_immediately)310 bool PersistentMap::erase( OString const & key, bool flush_immediately )
311 {
312 if( m_bReadOnly)
313 return false;
314 size_t nCount = m_entries.erase( key);
315 if( !nCount)
316 return false;
317 m_bIsDirty = true;
318 if( flush_immediately)
319 flush();
320 return true;
321 }
322
323 //______________________________________________________________________________
getEntries() const324 t_string2string_map PersistentMap::getEntries() const
325 {
326 // TODO: return by const reference instead?
327 return m_entries;
328 }
329
330 }
331
332