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/*
* linux/fs/hfs/file_hdr.c
*
* Copyright (C) 1995-1997 Paul H. Hargrove
* This file may be distributed under the terms of the GNU General Public License.
*
* This file contains the file_ops and inode_ops for the metadata
* files under the AppleDouble and Netatalk representations.
*
* The source code distributions of Netatalk, versions 1.3.3b2 and
* 1.4b2, were used as a specification of the location and format of
* files used by Netatalk's afpd. No code from Netatalk appears in
* hfs_fs. hfs_fs is not a work ``derived'' from Netatalk in the
* sense of intellectual property law.
*
* "XXX" in a comment is a note to myself to consider changing something.
*
* In function preconditions the term "valid" applied to a pointer to
* a structure means that the pointer is non-NULL and the structure it
* points to has all fields initialized to consistent values.
*
* XXX: Note the reason that there is not bmap() for AppleDouble
* header files is that dynamic nature of their structure make it
* very difficult to safely mmap them. Maybe in the distant future
* I'll get bored enough to implement it.
*/
#include "hfs.h"
#include <linux/hfs_fs_sb.h>
#include <linux/hfs_fs_i.h>
#include <linux/hfs_fs.h>
/* prodos types */
#define PRODOSI_FTYPE_DIR 0x0F
#define PRODOSI_FTYPE_TEXT 0x04
#define PRODOSI_FTYPE_8BIT 0xFF
#define PRODOSI_FTYPE_16BIT 0xB3
#define PRODOSI_AUXTYPE_DIR 0x0200
/*================ Forward declarations ================*/
static loff_t hdr_llseek(struct file *, loff_t, int);
static hfs_rwret_t hdr_read(struct file *, char *, hfs_rwarg_t, loff_t *);
static hfs_rwret_t hdr_write(struct file *, const char *,
hfs_rwarg_t, loff_t *);
/*================ Global variables ================*/
struct file_operations hfs_hdr_operations = {
llseek: hdr_llseek,
read: hdr_read,
write: hdr_write,
fsync: file_fsync,
};
struct inode_operations hfs_hdr_inode_operations = {
setattr: hfs_notify_change_hdr,
};
const struct hfs_hdr_layout hfs_dbl_fil_hdr_layout = {
__constant_htonl(HFS_DBL_MAGIC), /* magic */
__constant_htonl(HFS_HDR_VERSION_2), /* version */
6, /* entries */
{ /* descr[] */
{HFS_HDR_FNAME, offsetof(struct hfs_dbl_hdr, real_name), ~0},
{HFS_HDR_DATES, offsetof(struct hfs_dbl_hdr, create_time), 16},
{HFS_HDR_FINFO, offsetof(struct hfs_dbl_hdr, finderinfo), 32},
{HFS_HDR_MACI, offsetof(struct hfs_dbl_hdr, fileinfo), 4},
{HFS_HDR_DID, offsetof(struct hfs_dbl_hdr, cnid), 4},
{HFS_HDR_RSRC, HFS_DBL_HDR_LEN, ~0}
},
{ /* order[] */
(struct hfs_hdr_descr *)&hfs_dbl_fil_hdr_layout.descr[0],
(struct hfs_hdr_descr *)&hfs_dbl_fil_hdr_layout.descr[1],
(struct hfs_hdr_descr *)&hfs_dbl_fil_hdr_layout.descr[2],
(struct hfs_hdr_descr *)&hfs_dbl_fil_hdr_layout.descr[3],
(struct hfs_hdr_descr *)&hfs_dbl_fil_hdr_layout.descr[4],
(struct hfs_hdr_descr *)&hfs_dbl_fil_hdr_layout.descr[5]
}
};
const struct hfs_hdr_layout hfs_dbl_dir_hdr_layout = {
__constant_htonl(HFS_DBL_MAGIC), /* magic */
__constant_htonl(HFS_HDR_VERSION_2), /* version */
5, /* entries */
{ /* descr[] */
{HFS_HDR_FNAME, offsetof(struct hfs_dbl_hdr, real_name), ~0},
{HFS_HDR_DATES, offsetof(struct hfs_dbl_hdr, create_time), 16},
{HFS_HDR_FINFO, offsetof(struct hfs_dbl_hdr, finderinfo), 32},
{HFS_HDR_MACI, offsetof(struct hfs_dbl_hdr, fileinfo), 4},
{HFS_HDR_DID, offsetof(struct hfs_dbl_hdr, cnid), 4}
},
{ /* order[] */
(struct hfs_hdr_descr *)&hfs_dbl_dir_hdr_layout.descr[0],
(struct hfs_hdr_descr *)&hfs_dbl_dir_hdr_layout.descr[1],
(struct hfs_hdr_descr *)&hfs_dbl_dir_hdr_layout.descr[2],
(struct hfs_hdr_descr *)&hfs_dbl_dir_hdr_layout.descr[3],
(struct hfs_hdr_descr *)&hfs_dbl_dir_hdr_layout.descr[4]
}
};
const struct hfs_hdr_layout hfs_nat2_hdr_layout = {
__constant_htonl(HFS_DBL_MAGIC), /* magic */
__constant_htonl(HFS_HDR_VERSION_2), /* version */
9, /* entries */
{ /* descr[] */
{HFS_HDR_FNAME, offsetof(struct hfs_dbl_hdr, real_name), ~0},
{HFS_HDR_COMNT, offsetof(struct hfs_dbl_hdr, comment), 0},
{HFS_HDR_DATES, offsetof(struct hfs_dbl_hdr, create_time), 16},
{HFS_HDR_FINFO, offsetof(struct hfs_dbl_hdr, finderinfo), 32},
{HFS_HDR_AFPI, offsetof(struct hfs_dbl_hdr, fileinfo), 4},
{HFS_HDR_DID, offsetof(struct hfs_dbl_hdr, cnid), 4},
{HFS_HDR_SNAME, offsetof(struct hfs_dbl_hdr, short_name), ~0},
{HFS_HDR_PRODOSI, offsetof(struct hfs_dbl_hdr, prodosi), 8},
{HFS_HDR_RSRC, HFS_NAT_HDR_LEN, ~0}
},
{ /* order[] */
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[0],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[1],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[2],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[3],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[4],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[5],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[6],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[7],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[8]
}
};
const struct hfs_hdr_layout hfs_nat_hdr_layout = {
__constant_htonl(HFS_DBL_MAGIC), /* magic */
__constant_htonl(HFS_HDR_VERSION_1), /* version */
5, /* entries */
{ /* descr[] */
{HFS_HDR_FNAME, offsetof(struct hfs_dbl_hdr, real_name), ~0},
{HFS_HDR_COMNT, offsetof(struct hfs_dbl_hdr, comment), 0},
{HFS_HDR_OLDI, offsetof(struct hfs_dbl_hdr, create_time), 16},
{HFS_HDR_FINFO, offsetof(struct hfs_dbl_hdr, finderinfo), 32},
{HFS_HDR_RSRC, HFS_NAT_HDR_LEN, ~0},
},
{ /* order[] */
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[0],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[1],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[2],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[3],
(struct hfs_hdr_descr *)&hfs_nat_hdr_layout.descr[4]
}
};
/*================ File-local variables ================*/
static const char fstype[16] =
{'M','a','c','i','n','t','o','s','h',' ',' ',' ',' ',' ',' ',' '};
/*================ File-local data types ================*/
struct hdr_hdr {
hfs_lword_t magic;
hfs_lword_t version;
hfs_byte_t filler[16];
hfs_word_t entries;
hfs_byte_t descrs[12*HFS_HDR_MAX];
} __attribute__((packed));
/*================ File-local functions ================*/
/*
* dlength()
*/
static int dlength(const struct hfs_hdr_descr *descr,
const struct hfs_cat_entry *entry)
{
hfs_u32 length = descr->length;
/* handle auto-sized entries */
if (length == ~0) {
switch (descr->id) {
case HFS_HDR_DATA:
if (entry->type == HFS_CDR_FIL) {
length = entry->u.file.data_fork.lsize;
} else {
length = 0;
}
break;
case HFS_HDR_RSRC:
if (entry->type == HFS_CDR_FIL) {
length = entry->u.file.rsrc_fork.lsize;
} else {
length = 0;
}
break;
case HFS_HDR_FNAME:
length = entry->key.CName.Len;
break;
case HFS_HDR_SNAME:
default:
length = 0;
}
}
return length;
}
/*
* hdr_build_meta()
*/
static void hdr_build_meta(struct hdr_hdr *meta,
const struct hfs_hdr_layout *layout,
const struct hfs_cat_entry *entry)
{
const struct hfs_hdr_descr *descr;
hfs_byte_t *ptr;
int lcv;
hfs_put_nl(layout->magic, meta->magic);
hfs_put_nl(layout->version, meta->version);
if (layout->version == htonl(HFS_HDR_VERSION_1)) {
memcpy(meta->filler, fstype, 16);
} else {
memset(meta->filler, 0, 16);
}
hfs_put_hs(layout->entries, meta->entries);
memset(meta->descrs, 0, sizeof(meta->descrs));
for (lcv = 0, descr = layout->descr, ptr = meta->descrs;
lcv < layout->entries; ++lcv, ++descr, ptr += 12) {
hfs_put_hl(descr->id, ptr);
hfs_put_hl(descr->offset, ptr + 4);
hfs_put_hl(dlength(descr, entry), ptr + 8);
}
}
/*
* dup_layout ()
*/
static struct hfs_hdr_layout *dup_layout(const struct hfs_hdr_layout *old)
{
struct hfs_hdr_layout *new;
int lcv;
if (HFS_NEW(new)) {
memcpy(new, old, sizeof(*new));
for (lcv = 0; lcv < new->entries; ++lcv) {
(char *)(new->order[lcv]) += (char *)new - (char *)old;
}
}
return new;
}
/*
* init_layout()
*/
static inline void init_layout(struct hfs_hdr_layout *layout,
const hfs_byte_t *descrs)
{
struct hfs_hdr_descr **base, **p, **q, *tmp;
int lcv, entries = layout->entries;
for (lcv = 0; lcv < entries; ++lcv, descrs += 12) {
layout->order[lcv] = &layout->descr[lcv];
layout->descr[lcv].id = hfs_get_hl(descrs);
layout->descr[lcv].offset = hfs_get_hl(descrs + 4);
layout->descr[lcv].length = hfs_get_hl(descrs + 8);
}
for (lcv = layout->entries; lcv < HFS_HDR_MAX; ++lcv) {
layout->order[lcv] = NULL;
layout->descr[lcv].id = 0;
layout->descr[lcv].offset = 0;
layout->descr[lcv].length = 0;
}
/* Sort the 'order' array using an insertion sort */
base = &layout->order[0];
for (p = (base+1); p < (base+entries); ++p) {
q=p;
while ((*q)->offset < (*(q-1))->offset) {
tmp = *q;
*q = *(q-1);
*(--q) = tmp;
if (q == base) break;
}
}
}
/*
* adjust_forks()
*/
static inline void adjust_forks(struct hfs_cat_entry *entry,
const struct hfs_hdr_layout *layout)
{
int lcv;
for (lcv = 0; lcv < layout->entries; ++lcv) {
const struct hfs_hdr_descr *descr = &layout->descr[lcv];
if ((descr->id == HFS_HDR_DATA) &&
(descr->length != entry->u.file.data_fork.lsize)) {
entry->u.file.data_fork.lsize = descr->length;
hfs_extent_adj(&entry->u.file.data_fork);
} else if ((descr->id == HFS_HDR_RSRC) &&
(descr->length != entry->u.file.rsrc_fork.lsize)) {
entry->u.file.rsrc_fork.lsize = descr->length;
hfs_extent_adj(&entry->u.file.rsrc_fork);
}
}
}
/*
* get_dates()
*/
static void get_dates(const struct hfs_cat_entry *entry,
const struct inode *inode, hfs_u32 dates[3])
{
dates[0] = hfs_m_to_htime(entry->create_date);
dates[1] = hfs_m_to_htime(entry->modify_date);
dates[2] = hfs_m_to_htime(entry->backup_date);
}
/*
* set_dates()
*/
static void set_dates(struct hfs_cat_entry *entry, struct inode *inode,
const hfs_u32 *dates)
{
hfs_u32 tmp;
tmp = hfs_h_to_mtime(dates[0]);
if (entry->create_date != tmp) {
entry->create_date = tmp;
hfs_cat_mark_dirty(entry);
}
tmp = hfs_h_to_mtime(dates[1]);
if (entry->modify_date != tmp) {
entry->modify_date = tmp;
inode->i_ctime = inode->i_atime = inode->i_mtime =
hfs_h_to_utime(dates[1]);
hfs_cat_mark_dirty(entry);
}
tmp = hfs_h_to_mtime(dates[2]);
if (entry->backup_date != tmp) {
entry->backup_date = tmp;
hfs_cat_mark_dirty(entry);
}
}
loff_t hdr_llseek(struct file *file, loff_t offset, int origin)
{
long long retval;
switch (origin) {
case 2:
offset += file->f_dentry->d_inode->i_size;
break;
case 1:
offset += file->f_pos;
}
retval = -EINVAL;
if (offset>=0 && offset<file->f_dentry->d_inode->i_size) {
if (offset != file->f_pos) {
file->f_pos = offset;
file->f_reada = 0;
file->f_version = ++event;
}
retval = offset;
}
return retval;
}
/*
* hdr_read()
*
* This is the read field in the inode_operations structure for
* header files. The purpose is to transfer up to 'count' bytes
* from the file corresponding to 'inode', beginning at
* 'filp->offset' bytes into the file. The data is transferred to
* user-space at the address 'buf'. Returns the number of bytes
* successfully transferred.
*/
/* XXX: what about the entry count changing on us? */
static hfs_rwret_t hdr_read(struct file * filp, char * buf,
hfs_rwarg_t count, loff_t *ppos)
{
struct inode *inode = filp->f_dentry->d_inode;
struct hfs_cat_entry *entry = HFS_I(inode)->entry;
const struct hfs_hdr_layout *layout;
off_t start, length, offset;
off_t pos = *ppos;
int left, lcv, read = 0;
if (!S_ISREG(inode->i_mode)) {
hfs_warn("hfs_hdr_read: mode = %07o\n",inode->i_mode);
return -EINVAL;
}
if (HFS_I(inode)->layout) {
layout = HFS_I(inode)->layout;
} else {
layout = HFS_I(inode)->default_layout;
}
/* Adjust count to fit within the bounds of the file */
if ((pos >= inode->i_size) || (count <= 0)) {
return 0;
} else if (count > inode->i_size - pos) {
count = inode->i_size - pos;
}
/* Handle the fixed-location portion */
length = sizeof(hfs_u32) + sizeof(hfs_u32) + 16 +
sizeof(hfs_u16) + layout->entries * (3 * sizeof(hfs_u32));
if (pos < length) {
struct hdr_hdr meta;
left = length - pos;
if (left > count) {
left = count;
}
hdr_build_meta(&meta, layout, entry);
left -= copy_to_user(buf, ((char *)&meta) + pos, left);
count -= left;
read += left;
pos += left;
buf += left;
}
if (!count) {
goto done;
}
/* Handle the actual data */
for (lcv = 0; count && (lcv < layout->entries); ++lcv) {
const struct hfs_hdr_descr *descr = layout->order[lcv];
struct hfs_fork *fork;
char tmp[16], *p;
off_t limit;
/* stop reading if we run out of descriptors early */
if (!descr) {
break;
}
/* find start and length of this entry */
start = descr->offset;
length = dlength(descr, entry);
/* Skip to next entry if this one is empty or isn't needed */
if (!length || (pos >= start + length)) {
continue;
}
/* Pad with zeros to the start of this entry if needed */
if (pos < start) {
left = start - pos;
if (left > count) {
left = count;
}
clear_user(buf, left);
count -= left;
read += left;
pos += left;
buf += left;
}
if (!count) {
goto done;
}
/* locate and/or construct the data for this entry */
fork = NULL;
p = NULL;
switch (descr->id) {
case HFS_HDR_DATA:
fork = &entry->u.file.data_fork;
limit = fork->lsize;
break;
case HFS_HDR_RSRC:
fork = &entry->u.file.rsrc_fork;
limit = fork->lsize;
break;
case HFS_HDR_FNAME:
p = entry->key.CName.Name;
limit = entry->key.CName.Len;
break;
case HFS_HDR_OLDI:
case HFS_HDR_DATES:
get_dates(entry, inode, (hfs_u32 *)tmp);
if (descr->id == HFS_HDR_DATES) {
/* XXX: access date. hfsplus actually
has this. */
memcpy(tmp + 12, tmp + 4, 4);
} else if ((entry->type == HFS_CDR_FIL) &&
(entry->u.file.flags & HFS_FIL_LOCK)) {
hfs_put_hl(HFS_AFP_RDONLY, tmp + 12);
} else {
hfs_put_nl(0, tmp + 12);
}
p = tmp;
limit = 16;
break;
case HFS_HDR_FINFO:
p = (char *)&entry->info;
limit = 32;
break;
case HFS_HDR_AFPI:
/* XXX: this needs to do more mac->afp mappings */
hfs_put_ns(0, tmp);
if ((entry->type == HFS_CDR_FIL) &&
(entry->u.file.flags & HFS_FIL_LOCK)) {
hfs_put_hs(HFS_AFP_RDONLY, tmp + 2);
} else {
hfs_put_ns(0, tmp + 2);
}
p = tmp;
limit = 4;
break;
case HFS_HDR_PRODOSI:
/* XXX: this needs to do mac->prodos translations */
memset(tmp, 0, 8);
#if 0
hfs_put_ns(0, tmp); /* access */
hfs_put_ns(0, tmp); /* type */
hfs_put_nl(0, tmp); /* aux type */
#endif
p = tmp;
limit = 8;
break;
case HFS_HDR_MACI:
hfs_put_ns(0, tmp);
if (entry->type == HFS_CDR_FIL) {
hfs_put_hs(entry->u.file.flags, tmp + 2);
} else {
hfs_put_ns(entry->u.dir.flags, tmp + 2);
}
p = tmp;
limit = 4;
break;
case HFS_HDR_DID:
/* if it's rootinfo, stick the next available did in
* the did slot. */
limit = 4;
if (entry->cnid == htonl(HFS_ROOT_CNID)) {
struct hfs_mdb *mdb = entry->mdb;
const struct hfs_name *reserved =
HFS_SB(mdb->sys_mdb)->s_reserved2;
while (reserved->Len) {
if (hfs_streq(reserved->Name,
reserved->Len,
entry->key.CName.Name,
entry->key.CName.Len)) {
hfs_put_hl(mdb->next_id, tmp);
p = tmp;
goto hfs_did_done;
}
reserved++;
}
}
p = (char *) &entry->cnid;
hfs_did_done:
break;
case HFS_HDR_SNAME:
default:
limit = 0;
}
/* limit the transfer to the available data
of to the stated length of the entry. */
if (length > limit) {
length = limit;
}
offset = pos - start;
left = length - offset;
if (left > count) {
left = count;
}
if (left <= 0) {
continue;
}
/* transfer the data */
if (p) {
left -= copy_to_user(buf, p + offset, left);
} else if (fork) {
left = hfs_do_read(inode, fork, offset, buf, left,
filp->f_reada != 0);
if (left > 0) {
filp->f_reada = 1;
} else if (!read) {
return left;
} else {
goto done;
}
}
count -= left;
read += left;
pos += left;
buf += left;
}
/* Pad the file out with zeros */
if (count) {
clear_user(buf, count);
read += count;
pos += count;
}
done:
if (read) {
inode->i_atime = CURRENT_TIME;
*ppos = pos;
mark_inode_dirty(inode);
}
return read;
}
/*
* hdr_write()
*
* This is the write() entry in the file_operations structure for
* header files. The purpose is to transfer up to 'count' bytes
* to the file corresponding to 'inode' beginning at offset
* '*ppos' from user-space at the address 'buf'.
* The return value is the number of bytes actually transferred.
*/
static hfs_rwret_t hdr_write(struct file *filp, const char *buf,
hfs_rwarg_t count, loff_t *ppos)
{
struct inode *inode = filp->f_dentry->d_inode;
struct hfs_cat_entry *entry = HFS_I(inode)->entry;
struct hfs_hdr_layout *layout;
off_t start, length, offset;
int left, lcv, written = 0;
struct hdr_hdr meta;
int built_meta = 0;
off_t pos;
if (!S_ISREG(inode->i_mode)) {
hfs_warn("hfs_hdr_write: mode = %07o\n", inode->i_mode);
return -EINVAL;
}
if (count <= 0) {
return 0;
}
pos = (filp->f_flags & O_APPEND) ? inode->i_size : *ppos;
if (!HFS_I(inode)->layout) {
HFS_I(inode)->layout = dup_layout(HFS_I(inode)->default_layout);
}
layout = HFS_I(inode)->layout;
/* Handle the 'magic', 'version', 'filler' and 'entries' fields */
length = sizeof(hfs_u32) + sizeof(hfs_u32) + 16 + sizeof(hfs_u16);
if (pos < length) {
hdr_build_meta(&meta, layout, entry);
built_meta = 1;
left = length - pos;
if (left > count) {
left = count;
}
left -= copy_from_user(((char *)&meta) + pos, buf, left);
layout->magic = hfs_get_nl(meta.magic);
layout->version = hfs_get_nl(meta.version);
layout->entries = hfs_get_hs(meta.entries);
if (layout->entries > HFS_HDR_MAX) {
/* XXX: should allocate slots dynamically */
hfs_warn("hfs_hdr_write: TRUNCATING TO %d "
"DESCRIPTORS\n", HFS_HDR_MAX);
layout->entries = HFS_HDR_MAX;
}
count -= left;
written += left;
pos += left;
buf += left;
}
if (!count) {
goto done;
}
/* We know for certain how many entries we have, so process them */
length += layout->entries * 3 * sizeof(hfs_u32);
if (pos < length) {
if (!built_meta) {
hdr_build_meta(&meta, layout, entry);
}
left = length - pos;
if (left > count) {
left = count;
}
left -= copy_from_user(((char *)&meta) + pos, buf, left);
init_layout(layout, meta.descrs);
count -= left;
written += left;
pos += left;
buf += left;
/* Handle possible size changes for the forks */
if (entry->type == HFS_CDR_FIL) {
adjust_forks(entry, layout);
hfs_cat_mark_dirty(entry);
}
}
/* Handle the actual data */
for (lcv = 0; count && (lcv < layout->entries); ++lcv) {
struct hfs_hdr_descr *descr = layout->order[lcv];
struct hfs_fork *fork;
char tmp[16], *p;
off_t limit;
/* stop writing if we run out of descriptors early */
if (!descr) {
break;
}
/* find start and length of this entry */
start = descr->offset;
if ((descr->id == HFS_HDR_DATA) ||
(descr->id == HFS_HDR_RSRC)) {
if (entry->type == HFS_CDR_FIL) {
length = 0x7fffffff - start;
} else {
continue;
}
} else {
length = dlength(descr, entry);
}
/* Trim length to avoid overlap with the next entry */
if (layout->order[lcv+1] &&
((start + length) > layout->order[lcv+1]->offset)) {
length = layout->order[lcv+1]->offset - start;
}
/* Skip to next entry if this one is empty or isn't needed */
if (!length || (pos >= start + length)) {
continue;
}
/* Skip any padding that may exist between entries */
if (pos < start) {
left = start - pos;
if (left > count) {
left = count;
}
count -= left;
written += left;
pos += left;
buf += left;
}
if (!count) {
goto done;
}
/* locate and/or construct the data for this entry */
fork = NULL;
p = NULL;
switch (descr->id) {
case HFS_HDR_DATA:
#if 0
/* Can't yet write to the data fork via a header file, since there is the
* possibility to write via the data file, and the only locking is at the
* inode level.
*/
fork = &entry->u.file.data_fork;
limit = length;
#else
limit = 0;
#endif
break;
case HFS_HDR_RSRC:
fork = &entry->u.file.rsrc_fork;
limit = length;
break;
case HFS_HDR_OLDI:
case HFS_HDR_DATES:
get_dates(entry, inode, (hfs_u32 *)tmp);
if (descr->id == HFS_HDR_DATES) {
memcpy(tmp + 12, tmp + 4, 4);
} else if ((entry->type == HFS_CDR_FIL) &&
(entry->u.file.flags & HFS_FIL_LOCK)) {
hfs_put_hl(HFS_AFP_RDONLY, tmp + 12);
} else {
hfs_put_nl(0, tmp + 12);
}
p = tmp;
limit = 16;
break;
case HFS_HDR_FINFO:
p = (char *)&entry->info;
limit = 32;
break;
case HFS_HDR_AFPI:
hfs_put_ns(0, tmp);
if ((entry->type == HFS_CDR_FIL) &&
(entry->u.file.flags & HFS_FIL_LOCK)) {
hfs_put_hs(HFS_AFP_RDONLY, tmp + 2);
} else {
hfs_put_ns(0, tmp + 2);
}
p = tmp;
limit = 4;
break;
case HFS_HDR_PRODOSI:
/* XXX: this needs to do mac->prodos translations */
memset(tmp, 0, 8);
#if 0
hfs_put_ns(0, tmp); /* access */
hfs_put_ns(0, tmp); /* type */
hfs_put_nl(0, tmp); /* aux type */
#endif
p = tmp;
limit = 8;
break;
case HFS_HDR_MACI:
hfs_put_ns(0, tmp);
if (entry->type == HFS_CDR_FIL) {
hfs_put_hs(entry->u.file.flags, tmp + 2);
} else {
hfs_put_ns(entry->u.dir.flags, tmp + 2);
}
p = tmp;
limit = 4;
break;
case HFS_HDR_FNAME: /* Can't rename a file this way */
case HFS_HDR_DID: /* can't specify a did this way */
default:
limit = 0;
}
/* limit the transfer to the available data
of to the stated length of the entry. */
if (length > limit) {
length = limit;
}
offset = pos - start;
left = length - offset;
if (left > count) {
left = count;
}
if (left <= 0) {
continue;
}
/* transfer the data from user space */
if (p) {
left -= copy_from_user(p + offset, buf, left);
} else if (fork) {
left = hfs_do_write(inode, fork, offset, buf, left);
}
/* process the data */
switch (descr->id) {
case HFS_HDR_OLDI:
set_dates(entry, inode, (hfs_u32 *)tmp);
if (entry->type == HFS_CDR_FIL) {
hfs_u8 new_flags = entry->u.file.flags;
if (hfs_get_nl(tmp+12) & htonl(HFS_AFP_WRI)) {
new_flags |= HFS_FIL_LOCK;
} else {
new_flags &= ~HFS_FIL_LOCK;
}
if (new_flags != entry->u.file.flags) {
entry->u.file.flags = new_flags;
hfs_cat_mark_dirty(entry);
hfs_file_fix_mode(entry);
}
}
break;
case HFS_HDR_DATES:
set_dates(entry, inode, (hfs_u32 *)tmp);
break;
case HFS_HDR_FINFO:
hfs_cat_mark_dirty(entry);
break;
case HFS_HDR_MACI:
if (entry->type == HFS_CDR_DIR) {
hfs_u16 new_flags = hfs_get_ns(tmp + 2);
if (entry->u.dir.flags != new_flags) {
entry->u.dir.flags = new_flags;
hfs_cat_mark_dirty(entry);
}
} else {
hfs_u8 new_flags = tmp[3];
hfs_u8 changed = entry->u.file.flags^new_flags;
if (changed) {
entry->u.file.flags = new_flags;
hfs_cat_mark_dirty(entry);
if (changed & HFS_FIL_LOCK) {
hfs_file_fix_mode(entry);
}
}
}
break;
case HFS_HDR_DATA:
case HFS_HDR_RSRC:
if (left <= 0) {
if (!written) {
return left;
} else {
goto done;
}
} else if (fork->lsize > descr->length) {
descr->length = fork->lsize;
}
break;
case HFS_HDR_FNAME: /* Can't rename a file this way */
case HFS_HDR_DID: /* Can't specify a did this way */
case HFS_HDR_PRODOSI: /* not implemented yet */
case HFS_HDR_AFPI: /* ditto */
default:
break;
}
count -= left;
written += left;
pos += left;
buf += left;
}
/* Skip any padding at the end */
if (count) {
written += count;
pos += count;
}
done:
*ppos = pos;
if (written > 0) {
if (pos > inode->i_size)
inode->i_size = pos;
inode->i_mtime = inode->i_atime = CURRENT_TIME;
mark_inode_dirty(inode);
}
return written;
}
/*
* hdr_truncate()
*
* This is the truncate field in the inode_operations structure for
* header files. The purpose is to allocate or release blocks as needed
* to satisfy a change in file length.
*/
void hdr_truncate(struct inode *inode, size_t size)
{
struct hfs_cat_entry *entry = HFS_I(inode)->entry;
struct hfs_hdr_layout *layout;
int lcv, last;
inode->i_size = size;
if (!HFS_I(inode)->layout) {
HFS_I(inode)->layout = dup_layout(HFS_I(inode)->default_layout);
}
layout = HFS_I(inode)->layout;
last = layout->entries - 1;
for (lcv = 0; lcv <= last; ++lcv) {
struct hfs_hdr_descr *descr = layout->order[lcv];
struct hfs_fork *fork;
hfs_u32 offset;
if (!descr) {
break;
}
if (descr->id == HFS_HDR_RSRC) {
fork = &entry->u.file.rsrc_fork;
#if 0
/* Can't yet truncate the data fork via a header file, since there is the
* possibility to truncate via the data file, and the only locking is at
* the inode level.
*/
} else if (descr->id == HFS_HDR_DATA) {
fork = &entry->u.file.data_fork;
#endif
} else {
continue;
}
offset = descr->offset;
if ((lcv != last) && ((offset + descr->length) <= size)) {
continue;
}
if (offset < size) {
descr->length = size - offset;
} else {
descr->length = 0;
}
if (fork->lsize != descr->length) {
fork->lsize = descr->length;
hfs_extent_adj(fork);
hfs_cat_mark_dirty(entry);
}
}
}
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