1 /*
2  * libhfs - library for reading and writing Macintosh HFS volumes
3  * Copyright (C) 1996-1998 Robert Leslie
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
18  * MA 02110-1301, USA.
19  *
20  * $Id: file.c,v 1.9 1998/11/02 22:08:59 rob Exp $
21  */
22 
23 #include "config.h"
24 #include "libhfs.h"
25 #include "file.h"
26 #include "btree.h"
27 #include "record.h"
28 #include "volume.h"
29 
30 /*
31  * NAME:	file->init()
32  * DESCRIPTION:	initialize file structure
33  */
f_init(hfsfile * file,hfsvol * vol,long cnid,const char * name)34 void f_init(hfsfile *file, hfsvol *vol, long cnid, const char *name)
35 {
36   int i;
37 
38   file->vol   = vol;
39   file->parid = 0;
40 
41   strcpy(file->name, name);
42 
43   file->cat.cdrType          = cdrFilRec;
44   file->cat.cdrResrv2        = 0;
45 
46   file->cat.u.fil.filFlags   = 0;
47   file->cat.u.fil.filTyp     = 0;
48 
49   file->cat.u.fil.filUsrWds.fdType       = 0;
50   file->cat.u.fil.filUsrWds.fdCreator    = 0;
51   file->cat.u.fil.filUsrWds.fdFlags      = 0;
52   file->cat.u.fil.filUsrWds.fdLocation.v = 0;
53   file->cat.u.fil.filUsrWds.fdLocation.h = 0;
54   file->cat.u.fil.filUsrWds.fdFldr       = 0;
55 
56   file->cat.u.fil.filFlNum   = cnid;
57   file->cat.u.fil.filStBlk   = 0;
58   file->cat.u.fil.filLgLen   = 0;
59   file->cat.u.fil.filPyLen   = 0;
60   file->cat.u.fil.filRStBlk  = 0;
61   file->cat.u.fil.filRLgLen  = 0;
62   file->cat.u.fil.filRPyLen  = 0;
63   file->cat.u.fil.filCrDat   = 0;
64   file->cat.u.fil.filMdDat   = 0;
65   file->cat.u.fil.filBkDat   = 0;
66 
67   file->cat.u.fil.filFndrInfo.fdIconID = 0;
68   for (i = 0; i < 4; ++i)
69     file->cat.u.fil.filFndrInfo.fdUnused[i] = 0;
70   file->cat.u.fil.filFndrInfo.fdComment = 0;
71   file->cat.u.fil.filFndrInfo.fdPutAway = 0;
72 
73   file->cat.u.fil.filClpSize = 0;
74 
75   for (i = 0; i < 3; ++i)
76     {
77       file->cat.u.fil.filExtRec[i].xdrStABN     = 0;
78       file->cat.u.fil.filExtRec[i].xdrNumABlks  = 0;
79 
80       file->cat.u.fil.filRExtRec[i].xdrStABN    = 0;
81       file->cat.u.fil.filRExtRec[i].xdrNumABlks = 0;
82     }
83 
84   file->cat.u.fil.filResrv   = 0;
85 
86   f_selectfork(file, fkData);
87 
88   file->flags = 0;
89 
90   file->prev  = NULL;
91   file->next  = NULL;
92 }
93 
94 /*
95  * NAME:	file->selectfork()
96  * DESCRIPTION:	choose a fork for file operations
97  */
f_selectfork(hfsfile * file,int fork)98 void f_selectfork(hfsfile *file, int fork)
99 {
100   file->fork = fork;
101 
102   memcpy(&file->ext, fork == fkData ?
103 	 &file->cat.u.fil.filExtRec : &file->cat.u.fil.filRExtRec,
104 	 sizeof(ExtDataRec));
105 
106   file->fabn = 0;
107   file->pos  = 0;
108 }
109 
110 /*
111  * NAME:	file->getptrs()
112  * DESCRIPTION:	make pointers to the current fork's lengths and extents
113  */
f_getptrs(hfsfile * file,ExtDataRec ** extrec,unsigned long ** lglen,unsigned long ** pylen)114 void f_getptrs(hfsfile *file, ExtDataRec **extrec,
115 	       unsigned long **lglen, unsigned long **pylen)
116 {
117   if (file->fork == fkData)
118     {
119       if (extrec)
120 	*extrec = &file->cat.u.fil.filExtRec;
121       if (lglen)
122 	*lglen  = &file->cat.u.fil.filLgLen;
123       if (pylen)
124 	*pylen  = &file->cat.u.fil.filPyLen;
125     }
126   else
127     {
128       if (extrec)
129 	*extrec = &file->cat.u.fil.filRExtRec;
130       if (lglen)
131 	*lglen  = &file->cat.u.fil.filRLgLen;
132       if (pylen)
133 	*pylen  = &file->cat.u.fil.filRPyLen;
134     }
135 }
136 
137 /*
138  * NAME:	file->doblock()
139  * DESCRIPTION:	read or write a numbered block from a file
140  */
f_doblock(hfsfile * file,unsigned long num,block * bp,int (* func)(hfsvol *,unsigned int,unsigned int,block *))141 int f_doblock(hfsfile *file, unsigned long num, block *bp,
142 	      int (*func)(hfsvol *, unsigned int, unsigned int, block *))
143 {
144   unsigned int abnum;
145   unsigned int blnum;
146   unsigned int fabn;
147   int i;
148 
149   abnum = num / file->vol->lpa;
150   blnum = num % file->vol->lpa;
151 
152   /* locate the appropriate extent record */
153 
154   fabn = file->fabn;
155 
156   if (abnum < fabn)
157     {
158       ExtDataRec *extrec;
159 
160       f_getptrs(file, &extrec, NULL, NULL);
161 
162       fabn = file->fabn = 0;
163       memcpy(&file->ext, extrec, sizeof(ExtDataRec));
164     }
165   else
166     abnum -= fabn;
167 
168   while (1)
169     {
170       unsigned int n;
171 
172       for (i = 0; i < 3; ++i)
173 	{
174 	  n = file->ext[i].xdrNumABlks;
175 
176 	  if (abnum < n)
177 	    return func(file->vol, file->ext[i].xdrStABN + abnum, blnum, bp);
178 
179 	  fabn  += n;
180 	  abnum -= n;
181 	}
182 
183       if (v_extsearch(file, fabn, &file->ext, NULL) <= 0)
184 	goto fail;
185 
186       file->fabn = fabn;
187     }
188 
189 fail:
190   return -1;
191 }
192