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#include <MacTypes.h> 38#include <MacErrors.h> 39#include <MacMemory.h> 40#include <Files.h> 41#include <TextUtils.h> 42#include <Aliases.h> 43 44#define __COMPILINGMOREFILES 45 46#include "FSpCompat.h" 47#include "FullPath.h" 48 49/* 50 IMPORTANT NOTE: 51 52 The use of full pathnames is strongly discouraged. Full pathnames are 53 particularly unreliable as a means of identifying files, directories 54 or volumes within your application, for two primary reasons: 55 56 � The user can change the name of any element in the path at virtually 57 any time. 58 � Volume names on the Macintosh are *not* unique. Multiple 59 mounted volumes can have the same name. For this reason, the use of 60 a full pathname to identify a specific volume may not produce the 61 results you expect. If more than one volume has the same name and 62 a full pathname is used, the File Manager currently uses the first 63 mounted volume it finds with a matching name in the volume queue. 64 65 In general, you should use a file�s name, parent directory ID, and 66 volume reference number to identify a file you want to open, delete, 67 or otherwise manipulate. 68 69 If you need to remember the location of a particular file across 70 subsequent system boots, use the Alias Manager to create an alias record 71 describing the file. If the Alias Manager is not available, you can save 72 the file�s name, its parent directory ID, and the name of the volume on 73 which it�s located. Although none of these methods is foolproof, they are 74 much more reliable than using full pathnames to identify files. 75 76 Nonetheless, it is sometimes useful to display a file�s full pathname to 77 the user. For example, a backup utility might display a list of full 78 pathnames of files as it copies them onto the backup medium. Or, a 79 utility might want to display a dialog box showing the full pathname of 80 a file when it needs the user�s confirmation to delete the file. No 81 matter how unreliable full pathnames may be from a file-specification 82 viewpoint, users understand them more readily than volume reference 83 numbers or directory IDs. (Hint: Use the TruncString function from 84 TextUtils.h with truncMiddle as the truncWhere argument to shorten 85 full pathnames to a displayable length.) 86 87 The following technique for constructing the full pathname of a file is 88 intended for display purposes only. Applications that depend on any 89 particular structure of a full pathname are likely to fail on alternate 90 foreign file systems or under future system software versions. 91*/ 92 93/*****************************************************************************/ 94 95pascal OSErr GetFullPath(short vRefNum, 96 long dirID, 97 ConstStr255Param name, 98 short *fullPathLength, 99 Handle *fullPath) 100{ 101 OSErr result; 102 FSSpec spec; 103 104 *fullPathLength = 0; 105 *fullPath = NULL; 106 107 result = FSMakeFSSpecCompat(vRefNum, dirID, name, &spec); 108 if ( (result == noErr) || (result == fnfErr) ) 109 { 110 result = FSpGetFullPath(&spec, fullPathLength, fullPath); 111 } 112 113 return ( result ); 114} 115 116/*****************************************************************************/ 117 118pascal OSErr FSpGetFullPath(const FSSpec *spec, 119 short *fullPathLength, 120 Handle *fullPath) 121{ 122 OSErr result; 123 OSErr realResult; 124 FSSpec tempSpec; 125 CInfoPBRec pb; 126 127 *fullPathLength = 0; 128 *fullPath = NULL; 129 130 131 /* Default to noErr */ 132 realResult = result = noErr; 133 134 /* work around Nav Services "bug" (it returns invalid FSSpecs with empty names) */ 135 if ( spec->name[0] == 0 ) 136 { 137 result = FSMakeFSSpecCompat(spec->vRefNum, spec->parID, spec->name, &tempSpec); 138 } 139 else 140 { 141 /* Make a copy of the input FSSpec that can be modified */ 142 BlockMoveData(spec, &tempSpec, sizeof(FSSpec)); 143 } 144 145 if ( result == noErr ) 146 { 147 if ( tempSpec.parID == fsRtParID ) 148 { 149 /* The object is a volume */ 150 151 /* Add a colon to make it a full pathname */ 152 ++tempSpec.name[0]; 153 tempSpec.name[tempSpec.name[0]] = ':'; 154 155 /* We're done */ 156 result = PtrToHand(&tempSpec.name[1], fullPath, tempSpec.name[0]); 157 } 158 else 159 { 160 /* The object isn't a volume */ 161 162 /* Is the object a file or a directory? */ 163 pb.dirInfo.ioNamePtr = tempSpec.name; 164 pb.dirInfo.ioVRefNum = tempSpec.vRefNum; 165 pb.dirInfo.ioDrDirID = tempSpec.parID; 166 pb.dirInfo.ioFDirIndex = 0; 167 result = PBGetCatInfoSync(&pb); 168 // Allow file/directory name at end of path to not exist. 169 realResult = result; 170 if ( (result == noErr) || (result == fnfErr) ) 171 { 172 /* if the object is a directory, append a colon so full pathname ends with colon */ 173 if ( (result == noErr) && (pb.hFileInfo.ioFlAttrib & kioFlAttribDirMask) != 0 ) 174 { 175 ++tempSpec.name[0]; 176 tempSpec.name[tempSpec.name[0]] = ':'; 177 } 178 179 /* Put the object name in first */ 180 result = PtrToHand(&tempSpec.name[1], fullPath, tempSpec.name[0]); 181 if ( result == noErr ) 182 { 183 /* Get the ancestor directory names */ 184 pb.dirInfo.ioNamePtr = tempSpec.name; 185 pb.dirInfo.ioVRefNum = tempSpec.vRefNum; 186 pb.dirInfo.ioDrParID = tempSpec.parID; 187 do /* loop until we have an error or find the root directory */ 188 { 189 pb.dirInfo.ioFDirIndex = -1; 190 pb.dirInfo.ioDrDirID = pb.dirInfo.ioDrParID; 191 result = PBGetCatInfoSync(&pb); 192 if ( result == noErr ) 193 { 194 /* Append colon to directory name */ 195 ++tempSpec.name[0]; 196 tempSpec.name[tempSpec.name[0]] = ':'; 197 198 /* Add directory name to beginning of fullPath */ 199 (void) Munger(*fullPath, 0, NULL, 0, &tempSpec.name[1], tempSpec.name[0]); 200 result = MemError(); 201 } 202 } while ( (result == noErr) && (pb.dirInfo.ioDrDirID != fsRtDirID) ); 203 } 204 } 205 } 206 } 207 208 if ( result == noErr ) 209 { 210 /* Return the length */ 211 *fullPathLength = GetHandleSize(*fullPath); 212 result = realResult; // return realResult in case it was fnfErr 213 } 214 else 215 { 216 /* Dispose of the handle and return NULL and zero length */ 217 if ( *fullPath != NULL ) 218 { 219 DisposeHandle(*fullPath); 220 } 221 *fullPath = NULL; 222 *fullPathLength = 0; 223 } 224 225 return ( result ); 226} 227 228/*****************************************************************************/ 229 230pascal OSErr FSpLocationFromFullPath(short fullPathLength, 231 const void *fullPath, 232 FSSpec *spec) 233{ 234 AliasHandle alias; 235 OSErr result; 236 Boolean wasChanged; 237 Str32 nullString; 238 239 /* Create a minimal alias from the full pathname */ 240 nullString[0] = 0; /* null string to indicate no zone or server name */ 241 result = NewAliasMinimalFromFullPath(fullPathLength, fullPath, nullString, nullString, &alias); 242 if ( result == noErr ) 243 { 244 /* Let the Alias Manager resolve the alias. */ 245 result = ResolveAlias(NULL, alias, spec, &wasChanged); 246 247 /* work around Alias Mgr sloppy volume matching bug */ 248 if ( spec->vRefNum == 0 ) 249 { 250 /* invalidate wrong FSSpec */ 251 spec->parID = 0; 252 spec->name[0] = 0; 253 result = nsvErr; 254 } 255 DisposeHandle((Handle)alias); /* Free up memory used */ 256 } 257 return ( result ); 258} 259 260/*****************************************************************************/ 261 262pascal OSErr LocationFromFullPath(short fullPathLength, 263 const void *fullPath, 264 short *vRefNum, 265 long *parID, 266 Str31 name) 267{ 268 OSErr result; 269 FSSpec spec; 270 271 result = FSpLocationFromFullPath(fullPathLength, fullPath, &spec); 272 if ( result == noErr ) 273 { 274 *vRefNum = spec.vRefNum; 275 *parID = spec.parID; 276 BlockMoveData(&spec.name[0], &name[0], spec.name[0] + 1); 277 } 278 return ( result ); 279} 280 281/*****************************************************************************/ 282 283