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* File hash.c - generate hash tables for iso9660 filesystem.
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Written by Eric Youngdale (1993).
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Copyright 1993 Yggdrasil Computing, Incorporated
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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#define HASH_FN(DEV, INO) ((DEV + INO + (INO >> 2) + (INO << 8)) % NR_HASH)
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static struct file_hash * hash_table[NR_HASH] = {0,};
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void FDECL1(add_hash, struct directory_entry *, spnt){
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struct file_hash * s_hash;
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unsigned int hash_number;
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if(spnt->size == 0 || spnt->starting_block == 0)
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if(spnt->size != 0 || spnt->starting_block != 0) {
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fprintf(stderr,"Non zero-length file assigned zero extent.\n");
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if (spnt->dev == (dev_t) UNCACHED_DEVICE || spnt->inode == UNCACHED_INODE) return;
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hash_number = HASH_FN((unsigned int) spnt->dev, (unsigned int) spnt->inode);
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if (verbose > 1) fprintf(stderr,"%s ",spnt->name);
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s_hash = (struct file_hash *) e_malloc(sizeof(struct file_hash));
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s_hash->next = hash_table[hash_number];
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s_hash->inode = spnt->inode;
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s_hash->dev = spnt->dev;
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s_hash->starting_block = spnt->starting_block;
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s_hash->size = spnt->size;
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hash_table[hash_number] = s_hash;
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struct file_hash * FDECL2(find_hash, dev_t, dev, ino_t, inode){
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unsigned int hash_number;
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struct file_hash * spnt;
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hash_number = HASH_FN((unsigned int) dev, (unsigned int) inode);
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if (dev == (dev_t) UNCACHED_DEVICE || inode == UNCACHED_INODE) return NULL;
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spnt = hash_table[hash_number];
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if(spnt->inode == inode && spnt->dev == dev) return spnt;
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static struct file_hash * directory_hash_table[NR_HASH] = {0,};
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void FDECL2(add_directory_hash, dev_t, dev, ino_t, inode){
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struct file_hash * s_hash;
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unsigned int hash_number;
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if (dev == (dev_t) UNCACHED_DEVICE || inode == UNCACHED_INODE) return;
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hash_number = HASH_FN((unsigned int) dev, (unsigned int) inode);
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s_hash = (struct file_hash *) e_malloc(sizeof(struct file_hash));
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s_hash->next = directory_hash_table[hash_number];
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s_hash->inode = inode;
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directory_hash_table[hash_number] = s_hash;
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struct file_hash * FDECL2(find_directory_hash, dev_t, dev, ino_t, inode){
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unsigned int hash_number;
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struct file_hash * spnt;
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hash_number = HASH_FN((unsigned int) dev, (unsigned int) inode);
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if (dev == (dev_t) UNCACHED_DEVICE || inode == UNCACHED_INODE) return NULL;
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spnt = directory_hash_table[hash_number];
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if(spnt->inode == inode && spnt->dev == dev) return spnt;
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struct name_hash * next;
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struct directory_entry * de;
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#define NR_NAME_HASH 128
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static struct name_hash * name_hash_table[NR_NAME_HASH] = {0,};
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* Find the hash bucket for this name.
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static unsigned int FDECL1(name_hash, const char *, name)
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unsigned int hash = 0;
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* Don't hash the iso9660 version number. This way
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* we can detect duplicates in cases where we have
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* directories (i.e. foo) and non-directories
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hash = (hash << 15) + (hash << 3) + (hash >> 3) + *p++;
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return hash % NR_NAME_HASH;
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void FDECL1(add_file_hash, struct directory_entry *, de){
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struct name_hash * new;
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new = (struct name_hash *) e_malloc(sizeof(struct name_hash));
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hash = name_hash(de->isorec.name);
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/* Now insert into the hash table */
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new->next = name_hash_table[hash];
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name_hash_table[hash] = new;
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struct directory_entry * FDECL1(find_file_hash, char *, name)
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struct name_hash * nh;
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for(nh = name_hash_table[name_hash(name)]; nh; nh = nh->next)
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p2 = nh->de->isorec.name;
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* Look for end of string, or a mismatch.
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if( (*p1 == '\0' || *p1 == ';')
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|| (*p2 == '\0' || *p2 == ';')
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* If we are at the end of both strings, then
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if( (*p1 == '\0' || *p1 == ';')
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&& (*p2 == '\0' || *p2 == ';') )
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int FDECL1(delete_file_hash, struct directory_entry *, de){
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struct name_hash * nh, *prev;
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hash = name_hash(de->isorec.name);
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for(nh = name_hash_table[hash]; nh; nh = nh->next) {
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if(nh->de == de) break;
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name_hash_table[hash] = nh->next;
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prev->next = nh->next;
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void flush_file_hash(){
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struct name_hash * nh, *nh1;
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for(i=0; i<NR_NAME_HASH; i++) {
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nh = name_hash_table[i];
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name_hash_table[i] = NULL;