bsd/miscfs/synthfs/synthfs_util.c

   1 /*
   2  * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* Copyright (c) 1998, Apple Computer, Inc. All rights reserved. */
  23 /*
  24  * Change History:
  25  *
  26  *      17-Aug-1999     Pat Dirks       New today.
  27  *
  28  */
  29
  30 #include <mach/mach_types.h>
  31
  32 #include <sys/param.h>
  33 #include <sys/systm.h>
  34 #include <sys/kernel.h>
  35 #include <sys/file.h>
  36 #include <sys/stat.h>
  37 #include <sys/buf.h>
  38 #include <sys/proc.h>
  39 #include <sys/conf.h>
  40 #include <sys/mount.h>
  41 #include <sys/vnode.h>
  42 #include <sys/malloc.h>
  43 #include <sys/dirent.h>
  44 #include <sys/namei.h>
  45 #include <sys/attr.h>
  46 #include <sys/time.h>
  47
  48 #include <sys/vm.h>
  49 #include <sys/errno.h>
  50 #include <vfs/vfs_support.h>
  51
  52 #include "synthfs.h"
  53
  54 struct synthfs_direntry_head {
  55         u_int32_t d_fileno;             /* file number of entry */
  56         u_int16_t d_reclen;             /* length of this record */
  57         u_int8_t  d_type;               /* file type, see below */
  58         u_int8_t  d_namlen;             /* length of string in d_name */
  59 };
  60
  61
  62 #define PATHSEPARATOR '/'
  63 #define ROOTDIRID 2
  64
  65 void synthfs_setupuio(struct iovec *iov,
  66                                           struct uio *uio,
  67                                           void *buffer,
  68                                           size_t bufsize,
  69                                           enum uio_seg space,
  70                                           enum uio_rw direction,
  71                                           struct proc *p) {
  72         iov->iov_base = (char *)buffer;
  73         iov->iov_len = bufsize;
  74
  75         uio->uio_iov = iov;
  76         uio->uio_iovcnt = 1;
  77         uio->uio_offset = 0;
  78         uio->uio_resid = bufsize;
  79         uio->uio_segflg = space;
  80         uio->uio_rw = direction;
  81         uio->uio_procp = p;
  82 }
  83
  84
  85 static int synthfs_insertnode(struct synthfsnode *newnode_sp, struct synthfsnode *parent_sp) {
  86         struct timeval now;
  87
  88         DBG_ASSERT(parent_sp->s_type == SYNTHFS_DIRECTORY);
  89
  90     TAILQ_INSERT_TAIL(&parent_sp->s_u.d.d_subnodes, newnode_sp, s_sibling);
  91         ++parent_sp->s_u.d.d_entrycount;
  92         newnode_sp->s_parent = parent_sp;
  93
  94     parent_sp->s_nodeflags |= IN_CHANGE | IN_MODIFIED;
  95     now = time;
  96         VOP_UPDATE(STOV(parent_sp), &now, &now, 0);
  97
  98         return 0;
  99 }
 100
 101
 102
 103 static int synthfs_newnode(struct mount *mp, struct vnode *dp, const char *name, unsigned long nodeid, mode_t mode, struct proc *p, struct vnode **vpp) {
 104         int result;
 105     struct synthfsnode *sp;
 106         struct vnode *vp;
 107     struct timeval now;
 108     char *nodename;
 109
 110     /* Allocate the synthfsnode now to avoid blocking between the call
 111        to getnewvnode(), below, and the initialization of v_data: */
 112     MALLOC(sp, struct synthfsnode *, sizeof(struct synthfsnode), M_SYNTHFS, M_WAITOK);
 113
 114     if (name == NULL) {
 115         MALLOC(nodename, char *, 1, M_TEMP, M_WAITOK);
 116         nodename[0] = 0;
 117     } else {
 118         MALLOC(nodename, char *, strlen(name) + 1, M_TEMP, M_WAITOK);
 119         strcpy(nodename, name);
 120     };
 121
 122         /*
 123            Note that getnewvnode() returns the vnode with a refcount of +1;
 124            this routine returns the newly created vnode with this positive refcount.
 125          */
 126     result = getnewvnode(VT_SYNTHFS, mp, synthfs_vnodeop_p, &vp);
 127     if (result != 0) {
 128         DBG_VOP(("getnewvnode failed with error code %d\n", result));
 129         FREE(nodename, M_TEMP);
 130         FREE(sp, M_TEMP);
 131         return result;
 132     }
 133     if (vp == NULL) {
 134         DBG_VOP(("getnewvnod returned NULL without an error!\n"));
 135         FREE(nodename, M_TEMP);
 136         FREE(sp, M_TEMP);
 137         return EINVAL;
 138     }
 139
 140     /* Initialize the relevant synthfsnode fields: */
 141     bzero(sp, sizeof(*sp));
 142     lockinit(&sp->s_lock, PINOD, "synthfsnode", 0, 0);
 143     sp->s_nodeid = nodeid;
 144
 145     /* Initialize all times from a consistent snapshot of the clock: */
 146     now = time;
 147     sp->s_createtime = now;
 148     sp->s_accesstime = now;
 149     sp->s_modificationtime = now;
 150     sp->s_changetime = now;
 151     sp->s_name = nodename;
 152     sp->s_mode = mode;
 153
 154     sp->s_vp = vp;
 155     vp->v_data = sp;
 156
 157     vget(vp, LK_EXCLUSIVE, p);
 158
 159     /* If there's a parent directory, update its subnode structures to insert this new node: */
 160     if (dp) {
 161         result = synthfs_insertnode(sp, VTOS(dp));
 162     };
 163
 164     *vpp = vp;
 165
 166     return result;
 167 }
 168
 169
 170
 171 int synthfs_remove_entry(struct vnode *vp) {
 172         struct synthfsnode *sp = VTOS(vp);
 173         struct synthfsnode *psp = sp->s_parent;
 174         struct timeval now;
 175
 176         if (psp) {
 177                 TAILQ_REMOVE(&psp->s_u.d.d_subnodes, sp, s_sibling);
 178                 --psp->s_u.d.d_entrycount;
 179
 180                 psp->s_nodeflags |= IN_CHANGE | IN_MODIFIED;
 181                 now = time;
 182                 VOP_UPDATE(STOV(psp), &now, &now, 0);
 183         };
 184
 185     return 0;
 186 }
 187
 188
 189
 190 int synthfs_move_rename_entry(struct vnode *source_vp, struct vnode *newparent_vp, char *new_name) {
 191         struct synthfsnode *source_sp = VTOS(source_vp);
 192         struct synthfsnode *parent_sp = VTOS(newparent_vp);
 193         char *new_name_ptr;
 194         int result = 0;
 195
 196         /* Unlink the entry from its current place: */
 197         result = synthfs_remove_entry(source_vp);
 198         if (result) goto err_exit;
 199
 200         /* Change the name as necessary: */
 201         if (new_name) {
 202                 FREE(source_sp->s_name, M_TEMP);
 203                 MALLOC(new_name_ptr, char *, strlen(new_name) + 1, M_TEMP, M_WAITOK);
 204                 strcpy(new_name_ptr, new_name);
 205                 source_sp->s_name = new_name_ptr;
 206         };
 207
 208         /* Insert the entry in its new home: */
 209         result = synthfs_insertnode(source_sp, parent_sp);
 210
 211 err_exit:
 212         return result;
 213 }
 214
 215
 216
 217 int synthfs_new_directory(struct mount *mp, struct vnode *dp, const char *name, unsigned long nodeid, mode_t mode, struct proc *p, struct vnode **vpp) {
 218         int result;
 219         struct vnode *vp;
 220     struct synthfsnode *sp;
 221
 222         result = synthfs_newnode(mp, dp, name, nodeid, mode, p, &vp);
 223         if (result) {
 224                 return result;
 225         };
 226     sp = VTOS(vp);
 227     sp->s_linkcount = 2;
 228
 229     /* Initialize the relevant vnode fields: */
 230     vp->v_type = VDIR;
 231     if (dp) {
 232         ++VTOS(dp)->s_linkcount;                                        /* Account for the [fictitious] ".." link */
 233     };
 234
 235     /* Set up the directory-specific fields: */
 236     sp->s_type = SYNTHFS_DIRECTORY;
 237     sp->s_u.d.d_entrycount = 0;                                         /* No entries in this directory yet */
 238     TAILQ_INIT(&sp->s_u.d.d_subnodes);                          /* No subnodes of this directory yet */
 239
 240     *vpp = vp;
 241
 242     return 0;
 243 }
 244
 245
 246
 247 int synthfs_remove_directory(struct vnode *vp) {
 248         struct synthfsnode *sp = VTOS(vp);
 249         struct synthfsnode *psp = sp->s_parent;
 250
 251         if (psp && (sp->s_type == SYNTHFS_DIRECTORY) && (psp != sp)) {
 252                 --psp->s_linkcount;                                     /* account for the [fictitious] ".." link now removed */
 253         };
 254
 255         /* Do the standard cleanup involved in pruning an entry from the filesystem: */
 256         return synthfs_remove_entry(vp);                        /* Do whatever standard cleanup is required */
 257 }
 258
 259
 260
 261 int synthfs_new_symlink(
 262                 struct mount *mp,
 263                 struct vnode *dp,
 264                 const char *name,
 265                 unsigned long nodeid,
 266                 char *targetstring,
 267                 struct proc *p,
 268                 struct vnode **vpp) {
 269
 270         int result;
 271         struct vnode *vp;
 272         struct synthfsnode *sp;
 273
 274         result = synthfs_newnode(mp, dp, name, nodeid, 0, p, &vp);
 275         if (result) {
 276                 return result;
 277         };
 278     sp = VTOS(vp);
 279     sp->s_linkcount = 1;
 280
 281     /* Initialize the relevant vnode fields: */
 282     vp->v_type = VLNK;
 283
 284     /* Set up the symlink-specific fields: */
 285     sp->s_type = SYNTHFS_SYMLINK;
 286     sp->s_u.s.s_length = strlen(targetstring);
 287     MALLOC(sp->s_u.s.s_symlinktarget, char *, sp->s_u.s.s_length + 1, M_TEMP, M_WAITOK);
 288     strcpy(sp->s_u.s.s_symlinktarget, targetstring);
 289
 290     *vpp = vp;
 291
 292     return 0;
 293 }
 294
 295
 296
 297 int synthfs_remove_symlink(struct vnode *vp) {
 298         struct synthfsnode *sp = VTOS(vp);
 299
 300         FREE(sp->s_u.s.s_symlinktarget, M_TEMP);
 301
 302         /* Do the standard cleanup involved in pruning an entry from the filesystem: */
 303         return synthfs_remove_entry(vp);                                        /* Do whatever standard cleanup is required */
 304 }
 305
 306
 307
 308
 309
 310
 311 long synthfs_adddirentry(u_int32_t fileno, u_int8_t type, const char *name, struct uio *uio) {
 312     struct synthfs_direntry_head direntry;
 313         long namelength;
 314     int padding;
 315     long padtext = 0;
 316     unsigned short direntrylength;
 317
 318     namelength = ((name == NULL) ? 0 : strlen(name) + 1);
 319     padding = (4 - (namelength & 3)) & 3;
 320     direntrylength = sizeof(struct synthfs_direntry_head) + namelength + padding;
 321
 322         direntry.d_fileno = fileno;
 323     direntry.d_reclen = direntrylength;
 324         direntry.d_type = type;
 325         direntry.d_namlen = namelength;
 326
 327     if (uio->uio_resid < direntry.d_reclen) {
 328         direntrylength = 0;
 329     } else {
 330         uiomove((caddr_t)(&direntry), sizeof(direntry), uio);
 331         if (name != NULL) {
 332             uiomove((caddr_t)name, namelength, uio);
 333         };
 334         if (padding > 0) {
 335             uiomove((caddr_t)&padtext, padding, uio);
 336         };
 337     };
 338
 339     return direntrylength;
 340 }
 341
 342