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-rw-r--r--genisoimage/hash.c404
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diff --git a/genisoimage/hash.c b/genisoimage/hash.c
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+/*
+ * This file has been modified for the cdrkit suite.
+ *
+ * The behaviour and appearence of the program code below can differ to a major
+ * extent from the version distributed by the original author(s).
+ *
+ * For details, see Changelog file distributed with the cdrkit package. If you
+ * received this file from another source then ask the distributing person for
+ * a log of modifications.
+ *
+ */
+
+/* @(#)hash.c 1.18 04/06/18 joerg */
+/* @(#)hash.c 1.23 06/10/04 joerg */
+/*
+ * File hash.c - generate hash tables for iso9660 filesystem.
+ *
+ * Written by Eric Youngdale (1993).
+ *
+ * Copyright 1993 Yggdrasil Computing, Incorporated
+ * Copyright (c) 1999,2000-2006 J. Schilling
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/* APPLE_HYB James Pearson j.pearson@ge.ucl.ac.uk 23/2/2000 */
+
+/*
+ * From jb@danware.dk:
+ *
+ * Cygwin fakes inodes by hashing file info, actual collisions observed!
+ * This is documented in the cygwin source, look at winsup/cygwin/path.cc
+ * and search for the word 'Hash'. On NT, cygwin ORs together the
+ * high and low 32 bits of the 64 bit genuine inode, look at fhandler.cc.
+ *
+ * Note: Other operating systems which support the FAT filesystem may
+ * have the same problem because FAT does not use the inode
+ * concept. For NTFS, genuine inode numbers exist, but they are
+ * 64 bits and available only through an open file handle.
+ *
+ * The solution is the new options -no-cache-inodes/-cache-inodes that
+ * allow to disable the genisoimage inode cache.
+ */
+
+#include <mconfig.h>
+#include "genisoimage.h"
+#include <schily.h>
+
+#define NR_HASH (16*1024)
+
+#define HASH_FN(DEV, INO) ((DEV + INO + (INO >> 8) + (INO << 16)) % NR_HASH)
+
+static struct file_hash *hash_table[NR_HASH];
+
+void add_hash(struct directory_entry *spnt);
+struct file_hash *find_hash(dev_t dev, ino_t inode);
+void flush_hash(void);
+void add_directory_hash(dev_t dev, ino_t inode);
+struct file_hash *find_directory_hash(dev_t dev, ino_t inode);
+static unsigned int name_hash(const char *name);
+void add_file_hash(struct directory_entry *de);
+struct directory_entry *find_file_hash(char *name);
+static BOOL isoname_endsok(char *name);
+int delete_file_hash(struct directory_entry *de);
+void flush_file_hash(void);
+
+void
+add_hash(struct directory_entry *spnt)
+{
+ struct file_hash *s_hash;
+ unsigned int hash_number;
+
+ if (spnt->size == 0 || spnt->starting_block == 0)
+ if (spnt->size != 0 && spnt->starting_block == 0) {
+ comerrno(EX_BAD,
+ "Non zero-length file '%s' assigned zero extent.\n",
+ spnt->name);
+ };
+
+ if (!cache_inodes)
+ return;
+ if (spnt->dev == UNCACHED_DEVICE &&
+ (spnt->inode == TABLE_INODE || spnt->inode == UNCACHED_INODE)) {
+ return;
+ }
+ hash_number = HASH_FN((unsigned int) spnt->dev,
+ (unsigned int) spnt->inode);
+
+#if 0
+ if (verbose > 1)
+ fprintf(stderr, "%s ", spnt->name);
+#endif
+ s_hash = (struct file_hash *) e_malloc(sizeof (struct file_hash));
+ s_hash->next = hash_table[hash_number];
+ s_hash->inode = spnt->inode;
+ s_hash->dev = spnt->dev;
+ s_hash->nlink = 0;
+ s_hash->starting_block = spnt->starting_block;
+ s_hash->size = spnt->size;
+#ifdef SORTING
+ s_hash->de = spnt;
+#endif /* SORTING */
+ hash_table[hash_number] = s_hash;
+}
+
+struct file_hash *
+find_hash(dev_t dev, ino_t inode)
+{
+ unsigned int hash_number;
+ struct file_hash *spnt;
+
+ if (!cache_inodes)
+ return (NULL);
+ if (dev == UNCACHED_DEVICE &&
+ (inode == TABLE_INODE || inode == UNCACHED_INODE))
+ return (NULL);
+
+ hash_number = HASH_FN((unsigned int) dev, (unsigned int) inode);
+ spnt = hash_table[hash_number];
+ while (spnt) {
+ if (spnt->inode == inode && spnt->dev == dev)
+ return (spnt);
+ spnt = spnt->next;
+ };
+ return (NULL);
+}
+
+/*
+ * based on flush_file_hash() below - needed as we want to re-use the
+ * file hash table.
+ */
+void
+flush_hash()
+{
+ struct file_hash *fh;
+ struct file_hash *fh1;
+ int i;
+
+ for (i = 0; i < NR_HASH; i++) {
+ fh = hash_table[i];
+ while (fh) {
+ fh1 = fh->next;
+ free(fh);
+ fh = fh1;
+ }
+ hash_table[i] = NULL;
+ }
+}
+
+static struct file_hash *directory_hash_table[NR_HASH];
+
+void
+add_directory_hash(dev_t dev, ino_t inode)
+{
+ struct file_hash *s_hash;
+ unsigned int hash_number;
+
+ if (!cache_inodes)
+ return;
+ if (dev == UNCACHED_DEVICE &&
+ (inode == TABLE_INODE || inode == UNCACHED_INODE))
+ return;
+
+ hash_number = HASH_FN((unsigned int) dev, (unsigned int) inode);
+
+ s_hash = (struct file_hash *) e_malloc(sizeof (struct file_hash));
+ s_hash->next = directory_hash_table[hash_number];
+ s_hash->inode = inode;
+ s_hash->dev = dev;
+ s_hash->nlink = 0;
+ directory_hash_table[hash_number] = s_hash;
+}
+
+struct file_hash *
+find_directory_hash(dev_t dev, ino_t inode)
+{
+ unsigned int hash_number;
+ struct file_hash *spnt;
+
+ if (!cache_inodes)
+ return (NULL);
+ if (dev == UNCACHED_DEVICE &&
+ (inode == TABLE_INODE || inode == UNCACHED_INODE))
+ return (NULL);
+
+ hash_number = HASH_FN((unsigned int) dev, (unsigned int) inode);
+ spnt = directory_hash_table[hash_number];
+ while (spnt) {
+ if (spnt->inode == inode && spnt->dev == dev)
+ return (spnt);
+ spnt = spnt->next;
+ };
+ return (NULL);
+}
+
+struct name_hash {
+ struct name_hash *next;
+ struct directory_entry *de;
+ int sum;
+};
+
+#define NR_NAME_HASH (256*1024)
+
+static struct name_hash *name_hash_table[NR_NAME_HASH] = {0, };
+
+/*
+ * Find the hash bucket for this name.
+ */
+static unsigned int
+name_hash(const char *name)
+{
+ unsigned int hash = 0;
+ const char *p;
+
+ p = name;
+
+ while (*p) {
+ /*
+ * Don't hash the iso9660 version number.
+ * This way we can detect duplicates in cases where we have
+ * directories (i.e. foo) and non-directories (i.e. foo;1).
+ */
+ if (*p == ';') {
+ break;
+ }
+ hash = (hash << 15) + (hash << 3) + (hash >> 3) + (*p++ & 0xFF);
+ }
+ return (hash % NR_NAME_HASH);
+}
+
+void
+add_file_hash(struct directory_entry *de)
+{
+ struct name_hash *new;
+ int hash;
+ Uchar *p;
+ int sum = 0;
+
+ new = (struct name_hash *) e_malloc(sizeof (struct name_hash));
+ new->de = de;
+ new->next = NULL;
+ for (p = (Uchar *)de->isorec.name; *p; p++) {
+ if (*p == ';')
+ break;
+ sum += *p & 0xFF;
+ }
+ new->sum = sum;
+ hash = name_hash(de->isorec.name);
+
+ /* Now insert into the hash table */
+ new->next = name_hash_table[hash];
+ name_hash_table[hash] = new;
+}
+
+struct directory_entry *
+find_file_hash(register char *name)
+{
+ register char *p1;
+ register char *p2;
+ register struct name_hash *nh;
+ register int sum = 0;
+
+ if (debug > 1)
+ fprintf(stderr, "find_hash('%s')\n", name);
+
+ for (p1 = name; *p1; p1++) {
+ if (*p1 == ';')
+ break;
+ sum += *p1 & 0xFF;
+ }
+
+ for (nh = name_hash_table[name_hash(name)]; nh; nh = nh->next) {
+ if (nh->sum != sum)
+ continue;
+
+ p1 = name;
+ p2 = nh->de->isorec.name;
+ if (debug > 1)
+ fprintf(stderr, "Checking name '%s' isorec.name '%s'\n", p1, p2);
+
+ /* Look for end of string, or a mismatch. */
+ while (1 == 1) {
+ if ((*p1 == '\0' || *p1 == ';') ||
+ (*p2 == '\0' || *p2 == ';') ||
+ (*p1 != *p2)) {
+ break;
+ }
+ p1++;
+ p2++;
+ }
+ if (!isoname_endsok(p1) || !isoname_endsok(p2)) {
+ if (debug > 1) {
+ if (!isoname_endsok(p1))
+ fprintf(stderr, "'%s' does NOT END OK\n", p1);
+ if (!isoname_endsok(p2))
+ fprintf(stderr, "'%s' does NOT END OK\n", p2);
+ }
+ /*
+ * If one file does not end with a valid version number
+ * and the other name ends here, we found a miss match.
+ */
+ if (*p1 == '\0' || *p2 == '\0')
+ continue;
+
+ if (*p1 == ';' && *p2 == ';') {
+ p1++;
+ p2++;
+ continue;
+ }
+ }
+
+ /*
+ * If we are at the end of both strings, then we have a match.
+ */
+ if ((*p1 == '\0' || *p1 == ';') &&
+ (*p2 == '\0' || *p2 == ';')) {
+ return (nh->de);
+ }
+ }
+ return (NULL);
+}
+
+/*
+ * The macro 'eo' is just an idea on how one might speed up isoname_endsok()
+ */
+#define eo(p) (((p)[0] == '\0') || \
+ ((p)[0] == ';' && (p)[1] == '1' && (p)[2] == '\0') || \
+ isoname_endsok(p))
+
+static BOOL
+isoname_endsok(char *name)
+{
+ int i;
+ char *p;
+
+ if (*name == '\0')
+ return (TRUE);
+ if (*name != ';')
+ return (FALSE);
+
+ for (p = ++name, i = 0; *p && i < 5; p++, i++) {
+ if (*p < '0' || *p > '9')
+ return (FALSE);
+ }
+ i = atoi(name);
+ if (i < 1 || i > 32767)
+ return (FALSE);
+ return (TRUE);
+}
+
+int
+delete_file_hash(struct directory_entry *de)
+{
+ struct name_hash *nh;
+ struct name_hash *prev;
+ int hash;
+
+ prev = NULL;
+ hash = name_hash(de->isorec.name);
+ for (nh = name_hash_table[hash]; nh; nh = nh->next) {
+ if (nh->de == de)
+ break;
+ prev = nh;
+ }
+ if (!nh)
+ return (1);
+ if (!prev)
+ name_hash_table[hash] = nh->next;
+ else
+ prev->next = nh->next;
+ free(nh);
+ return (0);
+}
+
+void
+flush_file_hash()
+{
+ struct name_hash *nh;
+ struct name_hash *nh1;
+ int i;
+
+ for (i = 0; i < NR_NAME_HASH; i++) {
+ nh = name_hash_table[i];
+ while (nh) {
+ nh1 = nh->next;
+ free(nh);
+ nh = nh1;
+ }
+ name_hash_table[i] = NULL;
+
+ }
+}
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