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-rw-r--r--fs/isofs/dir.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/fs/isofs/dir.c b/fs/isofs/dir.c
new file mode 100644
index 000000000..b1934db04
--- /dev/null
+++ b/fs/isofs/dir.c
@@ -0,0 +1,258 @@
+/*
+ * linux/fs/isofs/dir.c
+ *
+ * (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO9660 filesystem.
+ *
+ * (C) 1991 Linus Torvalds - minix filesystem
+ *
+ * isofs directory handling functions
+ */
+
+#include <linux/errno.h>
+
+#include <asm/segment.h>
+
+#include <linux/fs.h>
+#include <linux/iso_fs.h>
+#include <linux/kernel.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/malloc.h>
+#include <linux/sched.h>
+#include <linux/locks.h>
+
+#define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
+#define ROUND_UP(x) (((x)+3) & ~3)
+
+static int isofs_readdir(struct inode *, struct file *, struct dirent *, int);
+
+static struct file_operations isofs_dir_operations = {
+ NULL, /* lseek - default */
+ NULL, /* read */
+ NULL, /* write - bad */
+ isofs_readdir, /* readdir */
+ NULL, /* select - default */
+ NULL, /* ioctl - default */
+ NULL, /* no special open code */
+ NULL, /* no special release code */
+ NULL /* fsync */
+};
+
+/*
+ * directories can handle most operations...
+ */
+struct inode_operations isofs_dir_inode_operations = {
+ &isofs_dir_operations, /* default directory file-ops */
+ NULL, /* create */
+ isofs_lookup, /* lookup */
+ NULL, /* link */
+ NULL, /* unlink */
+ NULL, /* symlink */
+ NULL, /* mkdir */
+ NULL, /* rmdir */
+ NULL, /* mknod */
+ NULL, /* rename */
+ NULL, /* readlink */
+ NULL, /* follow_link */
+ isofs_bmap, /* bmap */
+ NULL, /* truncate */
+ NULL /* permission */
+};
+
+static int isofs_readdir(struct inode * inode, struct file * filp,
+ struct dirent * dirent, int count)
+{
+ unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
+ unsigned char bufbits = ISOFS_BUFFER_BITS(inode);
+ unsigned int block,offset,i, j;
+ char c = 0;
+ int inode_number;
+ struct buffer_head * bh;
+ void * cpnt = NULL;
+ unsigned int old_offset;
+ int dlen, rrflag;
+ int high_sierra = 0;
+ char * dpnt, *dpnt1;
+ struct iso_directory_record * de;
+
+ dpnt1 = NULL;
+ if (!inode || !S_ISDIR(inode->i_mode))
+ return -EBADF;
+
+ offset = filp->f_pos & (bufsize - 1);
+ block = isofs_bmap(inode,filp->f_pos>>bufbits);
+
+ if(!block) return 0;
+
+ if(!(bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size)))
+ return 0;
+
+ while (filp->f_pos < inode->i_size) {
+#ifdef DEBUG
+ printk("Block, offset, f_pos: %x %x %x\n",
+ block, offset, filp->f_pos);
+#endif
+ de = (struct iso_directory_record *) (bh->b_data + offset);
+ inode_number = (block << bufbits) + (offset & (bufsize - 1));
+
+ /* If the length byte is zero, we should move on to the next
+ CDROM sector. If we are at the end of the directory, we
+ kick out of the while loop. */
+
+ if (*((unsigned char *) de) == 0) {
+ brelse(bh);
+ offset = 0;
+ filp->f_pos = ((filp->f_pos & ~(ISOFS_BLOCK_SIZE - 1))
+ + ISOFS_BLOCK_SIZE);
+ block = isofs_bmap(inode,(filp->f_pos)>>bufbits);
+ if (!block
+ || !(bh = breada(inode->i_dev, block, bufsize, filp->f_pos,
+ inode->i_size)))
+ return 0;
+ continue;
+ }
+
+ /* Make sure that the entire directory record is in the
+ current bh block.
+ If not, we malloc a buffer, and put the two halves together,
+ so that we can cleanly read the block */
+
+ old_offset = offset;
+ offset += *((unsigned char *) de);
+ filp->f_pos += *((unsigned char *) de);
+
+ if (offset > bufsize) {
+ unsigned int frag1;
+ frag1 = bufsize - old_offset;
+ cpnt = kmalloc(*((unsigned char *) de),GFP_KERNEL);
+ if (!cpnt) return 0;
+ memcpy(cpnt, bh->b_data + old_offset, frag1);
+ de = (struct iso_directory_record *) ((char *)cpnt);
+ brelse(bh);
+ offset = filp->f_pos & (bufsize - 1);
+ block = isofs_bmap(inode,(filp->f_pos)>> bufbits);
+ if (!block
+ || !(bh = breada(inode->i_dev, block, bufsize,
+ filp->f_pos, inode->i_size))) {
+ kfree(cpnt);
+ return 0;
+ };
+ memcpy((char *)cpnt+frag1, bh->b_data, offset);
+ }
+
+ /* Handle the case of the '.' directory */
+
+ rrflag = 0;
+ i = 1;
+ if (de->name_len[0] == 1 && de->name[0] == 0) {
+ put_fs_byte('.',dirent->d_name);
+ inode_number = inode->i_ino;
+ dpnt = ".";
+ }
+
+ /* Handle the case of the '..' directory */
+
+ else if (de->name_len[0] == 1 && de->name[0] == 1) {
+ put_fs_byte('.',dirent->d_name);
+ put_fs_byte('.',dirent->d_name+1);
+ i = 2;
+ dpnt = "..";
+ if((inode->i_sb->u.isofs_sb.s_firstdatazone) != inode->i_ino)
+ inode_number = inode->u.isofs_i.i_backlink;
+ else
+ inode_number = inode->i_ino;
+
+ /* This should never happen, but who knows. Try to be forgiving */
+ if(inode_number == -1) {
+ inode_number =
+ isofs_lookup_grandparent(inode,
+ find_rock_ridge_relocation(de, inode));
+ if(inode_number == -1){ /* Should never happen */
+ printk("Backlink not properly set.\n");
+ goto out;
+ };
+ }
+ }
+
+ /* Handle everything else. Do name translation if there
+ is no Rock Ridge NM field. */
+
+ else {
+ /* Do not report hidden or associated files */
+ high_sierra = inode->i_sb->u.isofs_sb.s_high_sierra;
+ if (de->flags[-high_sierra] & 5) {
+ if (cpnt) {
+ kfree(cpnt);
+ cpnt = NULL;
+ };
+ continue;
+ }
+ dlen = de->name_len[0];
+ dpnt = de->name;
+ i = dlen;
+ rrflag = get_rock_ridge_filename(de, &dpnt, &dlen, inode);
+ if (rrflag) {
+ if (rrflag == -1) { /* This is a rock ridge reloc dir */
+ if (cpnt) {
+ kfree(cpnt);
+ cpnt = NULL;
+ };
+ continue;
+ };
+ i = dlen;
+ }
+ else
+ if(inode->i_sb->u.isofs_sb.s_mapping == 'n') {
+ dpnt1 = dpnt;
+ dpnt = kmalloc(dlen, GFP_KERNEL);
+ if (!dpnt) goto out;
+ for (i = 0; i < dlen && i < NAME_MAX; i++) {
+ if (!(c = dpnt1[i])) break;
+ if (c >= 'A' && c <= 'Z') c |= 0x20; /* lower case */
+ if (c == '.' && i == dlen-3 && de->name[i+1] == ';' && de->name[i+2] == '1')
+ break; /* Drop trailing '.;1' (ISO9660:1988 7.5.1 requires period) */
+ if (c == ';' && i == dlen-2 && de->name[i+1] == '1')
+ break; /* Drop trailing ';1' */
+ if (c == ';') c = '.'; /* Convert remaining ';' to '.' */
+ dpnt[i] = c;
+ }
+ }
+ for(j=0; j<i; j++)
+ put_fs_byte(dpnt[j],j+dirent->d_name); /* And save it */
+ if(dpnt1) {
+ kfree(dpnt);
+ dpnt = dpnt1;
+ }
+
+ dcache_add(inode, dpnt, i, inode_number);
+ };
+#if 0
+ printk("Nchar: %d\n",i);
+#endif
+
+ if (rrflag) kfree(dpnt);
+ if (cpnt) {
+ kfree(cpnt);
+ cpnt = NULL;
+ };
+
+ if (i) {
+ put_fs_long(inode_number, &dirent->d_ino);
+ put_fs_byte(0,i+dirent->d_name);
+ put_fs_word(i,&dirent->d_reclen);
+ brelse(bh);
+ return ROUND_UP(NAME_OFFSET(dirent) + i + 1);
+ }
+ }
+ /* We go here for any condition we cannot handle. We also drop through
+ to here at the end of the directory. */
+ out:
+ if (cpnt)
+ kfree(cpnt);
+ brelse(bh);
+ return 0;
+}
+
+
+
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