1 /*
2 File: FullPath.c
3
4 Contains: Routines for dealing with full pathnames... if you really must.
5
6 Version: MoreFiles
7
8 Copyright: � 1995-2001 by Apple Computer, Inc., all rights reserved.
9
10 You may incorporate this sample code into your applications without
11 restriction, though the sample code has been provided "AS IS" and the
12 responsibility for its operation is 100% yours. However, what you are
13 not permitted to do is to redistribute the source as "DSC Sample Code"
14 after having made changes. If you're going to re-distribute the source,
15 we require that you make it clear in the source that the code was
16 descended from Apple Sample Code, but that you've made changes.
17
18 File Ownership:
19
20 DRI: Apple Macintosh Developer Technical Support
21
22 Other Contact: Apple Macintosh Developer Technical Support
23 <http://developer.apple.com/bugreporter/>
24
25 Technology: DTS Sample Code
26
27 Writers:
28
29 (JL) Jim Luther
30
31 Change History (most recent first):
32
33 <2> 2/7/01 JL Added standard header. Updated names of includes.
34 <1> 12/06/99 JL MoreFiles 1.5.
35 */
36
37 /*
38 This file has been slightly modified from the original by
39 the National Center for Biotechnology Information, National
40 Institutes of Health, Bethesda, Maryland, USA.
41 */
42
43 /* C++ style comments converted to C comments by NCBI */
44
45
46 #ifndef WIN32
47
48 #include <MacTypes.h>
49 #include <MacErrors.h>
50 #include <MacMemory.h>
51 #include <Files.h>
52 #include <TextUtils.h>
53 #include <Aliases.h>
54
55 #define __COMPILINGMOREFILES
56
57 #include "FSpCompat.h"
58 #include "FullPath.h"
59
60 /*
61 IMPORTANT NOTE:
62
63 The use of full pathnames is strongly discouraged. Full pathnames are
64 particularly unreliable as a means of identifying files, directories
65 or volumes within your application, for two primary reasons:
66
67 � The user can change the name of any element in the path at virtually
68 any time.
69 � Volume names on the Macintosh are *not* unique. Multiple
70 mounted volumes can have the same name. For this reason, the use of
71 a full pathname to identify a specific volume may not produce the
72 results you expect. If more than one volume has the same name and
73 a full pathname is used, the File Manager currently uses the first
74 mounted volume it finds with a matching name in the volume queue.
75
76 In general, you should use a file�s name, parent directory ID, and
77 volume reference number to identify a file you want to open, delete,
78 or otherwise manipulate.
79
80 If you need to remember the location of a particular file across
81 subsequent system boots, use the Alias Manager to create an alias record
82 describing the file. If the Alias Manager is not available, you can save
83 the file�s name, its parent directory ID, and the name of the volume on
84 which it�s located. Although none of these methods is foolproof, they are
85 much more reliable than using full pathnames to identify files.
86
87 Nonetheless, it is sometimes useful to display a file�s full pathname to
88 the user. For example, a backup utility might display a list of full
89 pathnames of files as it copies them onto the backup medium. Or, a
90 utility might want to display a dialog box showing the full pathname of
91 a file when it needs the user�s confirmation to delete the file. No
92 matter how unreliable full pathnames may be from a file-specification
93 viewpoint, users understand them more readily than volume reference
94 numbers or directory IDs. (Hint: Use the TruncString function from
95 TextUtils.h with truncMiddle as the truncWhere argument to shorten
96 full pathnames to a displayable length.)
97
98 The following technique for constructing the full pathname of a file is
99 intended for display purposes only. Applications that depend on any
100 particular structure of a full pathname are likely to fail on alternate
101 foreign file systems or under future system software versions.
102 */
103
104 /*****************************************************************************/
105
GetFullPath(short vRefNum,long dirID,ConstStr255Param name,short * fullPathLength,Handle * fullPath)106 pascal OSErr GetFullPath(short vRefNum,
107 long dirID,
108 ConstStr255Param name,
109 short *fullPathLength,
110 Handle *fullPath)
111 {
112 OSErr result;
113 FSSpec spec;
114
115 *fullPathLength = 0;
116 *fullPath = NULL;
117
118 result = FSMakeFSSpecCompat(vRefNum, dirID, name, &spec);
119 if ( (result == noErr) || (result == fnfErr) )
120 {
121 result = FSpGetFullPath(&spec, fullPathLength, fullPath);
122 }
123
124 return ( result );
125 }
126
127 /*****************************************************************************/
128
FSpGetFullPath(const FSSpec * spec,short * fullPathLength,Handle * fullPath)129 pascal OSErr FSpGetFullPath(const FSSpec *spec,
130 short *fullPathLength,
131 Handle *fullPath)
132 {
133 OSErr result;
134 OSErr realResult;
135 FSSpec tempSpec;
136 CInfoPBRec pb;
137
138 *fullPathLength = 0;
139 *fullPath = NULL;
140
141
142 /* Default to noErr */
143 realResult = result = noErr;
144
145 /* work around Nav Services "bug" (it returns invalid FSSpecs with empty names) */
146 if ( spec->name[0] == 0 )
147 {
148 result = FSMakeFSSpecCompat(spec->vRefNum, spec->parID, spec->name, &tempSpec);
149 }
150 else
151 {
152 /* Make a copy of the input FSSpec that can be modified */
153 BlockMoveData(spec, &tempSpec, sizeof(FSSpec));
154 }
155
156 if ( result == noErr )
157 {
158 if ( tempSpec.parID == fsRtParID )
159 {
160 /* The object is a volume */
161
162 /* Add a colon to make it a full pathname */
163 ++tempSpec.name[0];
164 tempSpec.name[tempSpec.name[0]] = ':';
165
166 /* We're done */
167 result = PtrToHand(&tempSpec.name[1], fullPath, tempSpec.name[0]);
168 }
169 else
170 {
171 /* The object isn't a volume */
172
173 /* Is the object a file or a directory? */
174 pb.dirInfo.ioNamePtr = tempSpec.name;
175 pb.dirInfo.ioVRefNum = tempSpec.vRefNum;
176 pb.dirInfo.ioDrDirID = tempSpec.parID;
177 pb.dirInfo.ioFDirIndex = 0;
178 result = PBGetCatInfoSync(&pb);
179 /* Allow file/directory name at end of path to not exist. */
180 realResult = result;
181 if ( (result == noErr) || (result == fnfErr) )
182 {
183 /* if the object is a directory, append a colon so full pathname ends with colon */
184 if ( (result == noErr) && (pb.hFileInfo.ioFlAttrib & kioFlAttribDirMask) != 0 )
185 {
186 ++tempSpec.name[0];
187 tempSpec.name[tempSpec.name[0]] = ':';
188 }
189
190 /* Put the object name in first */
191 result = PtrToHand(&tempSpec.name[1], fullPath, tempSpec.name[0]);
192 if ( result == noErr )
193 {
194 /* Get the ancestor directory names */
195 pb.dirInfo.ioNamePtr = tempSpec.name;
196 pb.dirInfo.ioVRefNum = tempSpec.vRefNum;
197 pb.dirInfo.ioDrParID = tempSpec.parID;
198 do /* loop until we have an error or find the root directory */
199 {
200 pb.dirInfo.ioFDirIndex = -1;
201 pb.dirInfo.ioDrDirID = pb.dirInfo.ioDrParID;
202 result = PBGetCatInfoSync(&pb);
203 if ( result == noErr )
204 {
205 /* Append colon to directory name */
206 ++tempSpec.name[0];
207 tempSpec.name[tempSpec.name[0]] = ':';
208
209 /* Add directory name to beginning of fullPath */
210 (void) Munger(*fullPath, 0, NULL, 0, &tempSpec.name[1], tempSpec.name[0]);
211 result = MemError();
212 }
213 } while ( (result == noErr) && (pb.dirInfo.ioDrDirID != fsRtDirID) );
214 }
215 }
216 }
217 }
218
219 if ( result == noErr )
220 {
221 /* Return the length */
222 *fullPathLength = GetHandleSize(*fullPath);
223 result = realResult; /* return realResult in case it was fnfErr */
224 }
225 else
226 {
227 /* Dispose of the handle and return NULL and zero length */
228 if ( *fullPath != NULL )
229 {
230 DisposeHandle(*fullPath);
231 }
232 *fullPath = NULL;
233 *fullPathLength = 0;
234 }
235
236 return ( result );
237 }
238
239 /*****************************************************************************/
240
FSpLocationFromFullPath(short fullPathLength,const void * fullPath,FSSpec * spec)241 pascal OSErr FSpLocationFromFullPath(short fullPathLength,
242 const void *fullPath,
243 FSSpec *spec)
244 {
245 AliasHandle alias;
246 OSErr result;
247 Boolean wasChanged;
248 Str32 nullString;
249
250 /* Create a minimal alias from the full pathname */
251 nullString[0] = 0; /* null string to indicate no zone or server name */
252 result = NewAliasMinimalFromFullPath(fullPathLength, fullPath, nullString, nullString, &alias);
253 if ( result == noErr )
254 {
255 /* Let the Alias Manager resolve the alias. */
256 result = ResolveAlias(NULL, alias, spec, &wasChanged);
257
258 /* work around Alias Mgr sloppy volume matching bug */
259 if ( spec->vRefNum == 0 )
260 {
261 /* invalidate wrong FSSpec */
262 spec->parID = 0;
263 spec->name[0] = 0;
264 result = nsvErr;
265 }
266 DisposeHandle((Handle)alias); /* Free up memory used */
267 }
268 return ( result );
269 }
270
271 /*****************************************************************************/
272
LocationFromFullPath(short fullPathLength,const void * fullPath,short * vRefNum,long * parID,Str31 name)273 pascal OSErr LocationFromFullPath(short fullPathLength,
274 const void *fullPath,
275 short *vRefNum,
276 long *parID,
277 Str31 name)
278 {
279 OSErr result;
280 FSSpec spec;
281
282 result = FSpLocationFromFullPath(fullPathLength, fullPath, &spec);
283 if ( result == noErr )
284 {
285 *vRefNum = spec.vRefNum;
286 *parID = spec.parID;
287 BlockMoveData(&spec.name[0], &name[0], spec.name[0] + 1);
288 }
289 return ( result );
290 }
291
292 /*****************************************************************************/
293
294 #endif /* WIN32 */
295