openenvutils/commandshell/shell/src/hashtable.c
changeset 0 2e3d3ce01487
child 4 0fdb7f6b0309
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/openenvutils/commandshell/shell/src/hashtable.c	Tue Feb 02 10:12:00 2010 +0200
@@ -0,0 +1,1571 @@
+//hashtable.c - hash tables
+//
+// © Portions Copyright (c) Symbian Software Ltd 2007. All rights reserved.
+//
+/*
+ * This file is part of zsh, the Z shell.
+ *
+ * Copyright (c) 1992-1997 Paul Falstad
+ * All rights reserved.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and to distribute modified versions of this software for any
+ * purpose, provided that the above copyright notice and the following
+ * two paragraphs appear in all copies of this software.
+ *
+ * In no event shall Paul Falstad or the Zsh Development Group be liable
+ * to any party for direct, indirect, special, incidental, or consequential
+ * damages arising out of the use of this software and its documentation,
+ * even if Paul Falstad and the Zsh Development Group have been advised of
+ * the possibility of such damage.
+ *
+ * Paul Falstad and the Zsh Development Group specifically disclaim any
+ * warranties, including, but not limited to, the implied warranties of
+ * merchantability and fitness for a particular purpose.  The software
+ * provided hereunder is on an "as is" basis, and Paul Falstad and the
+ * Zsh Development Group have no obligation to provide maintenance,
+ * support, updates, enhancements, or modifications.
+ *
+ */
+#include "config.h"
+
+#ifdef __SYMBIAN32__
+#ifdef __WINSCW__
+#pragma warn_unusedarg off
+#endif//__WINSCW__
+#endif//__SYMBIAN32__
+
+#ifdef ZSH_HASH_DEBUG
+# define HASHTABLE_DEBUG_MEMBERS \
+    /* Members of struct hashtable used for debugging hash tables */ \
+    HashTable next, last;	/* linked list of all hash tables           */ \
+    char *tablename;		/* string containing name of the hash table */ \
+    PrintTableStats printinfo;	/* pointer to function to print table stats */
+#else /* !ZSH_HASH_DEBUG */
+# define HASHTABLE_DEBUG_MEMBERS
+#endif /* !ZSH_HASH_DEBUG */
+
+#define HASHTABLE_INTERNAL_MEMBERS \
+    ScanStatus scan;		/* status of a scan over this hashtable     */ \
+    HASHTABLE_DEBUG_MEMBERS
+
+typedef struct scanstatus *ScanStatus;
+
+#include "zsh.mdh"
+#include "hashtable.pro"
+
+/* Structure for recording status of a hashtable scan in progress.  When a *
+ * scan starts, the .scan member of the hashtable structure points to one  *
+ * of these.  That member being non-NULL disables resizing of the          *
+ * hashtable (when adding elements).  When elements are deleted, the       *
+ * contents of this structure is used to make sure the scan won't stumble  *
+ * into the deleted element.                                               */
+
+struct scanstatus {
+    int sorted;
+    union {
+	struct {
+	    HashNode *tab;
+	    int ct;
+	} s;
+	HashNode u;
+    } u;
+};
+
+/********************************/
+/* Generic Hash Table functions */
+/********************************/
+
+#ifdef ZSH_HASH_DEBUG
+static HashTable firstht, lastht;
+#endif /* ZSH_HASH_DEBUG */
+
+/* Generic hash function */
+
+/**/
+mod_export unsigned
+hasher(char *str)
+{
+    unsigned hashval = 0, c;
+
+    while ((c = *((unsigned char *) str++)))
+	hashval += (hashval << 5) + c;
+
+    return hashval;
+}
+
+/* Get a new hash table */
+
+/**/
+mod_export HashTable
+newhashtable(int size, UNUSED(char const *name), UNUSED(PrintTableStats printinfo))
+{
+    HashTable ht;
+
+    ht = (HashTable) zshcalloc(sizeof *ht);
+#ifdef ZSH_HASH_DEBUG
+    ht->next = NULL;
+    if(!firstht)
+	firstht = ht;
+    ht->last = lastht;
+    if(lastht)
+	lastht->next = ht;
+    lastht = ht;
+    ht->printinfo = printinfo ? printinfo : printhashtabinfo;
+    ht->tablename = ztrdup(name);
+#endif /* ZSH_HASH_DEBUG */
+    ht->nodes = (HashNode *) zshcalloc(size * sizeof(HashNode));
+    ht->hsize = size;
+    ht->ct = 0;
+    ht->scan = NULL;
+    ht->scantab = NULL;
+    return ht;
+}
+
+/* Delete a hash table.  After this function has been used, any *
+ * existing pointers to the hash table are invalid.             */
+
+/**/
+mod_export void
+deletehashtable(HashTable ht)
+{
+    ht->emptytable(ht);
+#ifdef ZSH_HASH_DEBUG
+    if(ht->next)
+	ht->next->last = ht->last;
+    else
+	lastht = ht->last;
+    if(ht->last)
+	ht->last->next = ht->next;
+    else
+	firstht = ht->next;
+    zsfree(ht->tablename);
+#endif /* ZSH_HASH_DEBUG */
+    zfree(ht->nodes, ht->hsize * sizeof(HashNode));
+    zfree(ht, sizeof(*ht));
+}
+
+/* Add a node to a hash table.                          *
+ * nam is the key to use in hashing.  nodeptr points    *
+ * to the node to add.  If there is already a node in   *
+ * the table with the same key, it is first freed, and  *
+ * then the new node is added.  If the number of nodes  *
+ * is now greater than twice the number of hash values, *
+ * the table is then expanded.                          */
+
+/**/
+mod_export void
+addhashnode(HashTable ht, char *nam, void *nodeptr)
+{
+    HashNode oldnode = addhashnode2(ht, nam, nodeptr);
+    if (oldnode)
+	ht->freenode(oldnode);
+}
+
+/* Add a node to a hash table, returning the old node on replacement. */
+
+/**/
+HashNode
+addhashnode2(HashTable ht, char *nam, void *nodeptr)
+{
+    unsigned hashval;
+    HashNode hn, hp, hq;
+
+    hn = (HashNode) nodeptr;
+    hn->nam = nam;
+
+    hashval = ht->hash(hn->nam) % ht->hsize;
+    hp = ht->nodes[hashval];
+
+    /* check if this is the first node for this hash value */
+    if (!hp) {
+	hn->next = NULL;
+	ht->nodes[hashval] = hn;
+	if (++ht->ct >= ht->hsize * 2 && !ht->scan)
+	    expandhashtable(ht);
+	return NULL;
+    }
+
+    /* else check if the first node contains the same key */
+    if (ht->cmpnodes(hp->nam, hn->nam) == 0) {
+	ht->nodes[hashval] = hn;
+	replacing:
+	hn->next = hp->next;
+	if(ht->scan) {
+	    if(ht->scan->sorted) {
+		HashNode *tab = ht->scan->u.s.tab;
+		int i;
+		for(i = ht->scan->u.s.ct; i--; )
+		    if(tab[i] == hp)
+			tab[i] = hn;
+	    } else if(ht->scan->u.u == hp)
+		ht->scan->u.u = hn;
+	}
+	return hp;
+    }
+
+    /* else run through the list and check all the keys */
+    hq = hp;
+    hp = hp->next;
+    for (; hp; hq = hp, hp = hp->next) {
+	if (ht->cmpnodes(hp->nam, hn->nam) == 0) {
+	    hq->next = hn;
+	    goto replacing;
+	}
+    }
+
+    /* else just add it at the front of the list */
+    hn->next = ht->nodes[hashval];
+    ht->nodes[hashval] = hn;
+    if (++ht->ct >= ht->hsize * 2 && !ht->scan)
+        expandhashtable(ht);
+    return NULL;
+}
+
+/* Get an enabled entry in a hash table.  *
+ * If successful, it returns a pointer to *
+ * the hashnode.  If the node is DISABLED *
+ * or isn't found, it returns NULL        */
+
+/**/
+mod_export HashNode
+gethashnode(HashTable ht, char *nam)
+{
+    unsigned hashval;
+    HashNode hp;
+
+    hashval = ht->hash(nam) % ht->hsize;
+    for (hp = ht->nodes[hashval]; hp; hp = hp->next) {
+	if (ht->cmpnodes(hp->nam, nam) == 0) {
+	    if (hp->flags & DISABLED)
+		return NULL;
+	    else
+		return hp;
+	}
+    }
+    return NULL;
+}
+
+/* Get an entry in a hash table.  It will *
+ * ignore the DISABLED flag and return a  *
+ * pointer to the hashnode if found, else *
+ * it returns NULL.                       */
+
+/**/
+mod_export HashNode
+gethashnode2(HashTable ht, char *nam)
+{
+    unsigned hashval;
+    HashNode hp;
+
+    hashval = ht->hash(nam) % ht->hsize;
+    for (hp = ht->nodes[hashval]; hp; hp = hp->next) {
+	if (ht->cmpnodes(hp->nam, nam) == 0)
+	    return hp;
+    }
+    return NULL;
+}
+
+/* Remove an entry from a hash table.           *
+ * If successful, it removes the node from the  *
+ * table and returns a pointer to it.  If there *
+ * is no such node, then it returns NULL        */
+
+/**/
+mod_export HashNode
+removehashnode(HashTable ht, char *nam)
+{
+    unsigned hashval;
+    HashNode hp, hq;
+
+    hashval = ht->hash(nam) % ht->hsize;
+    hp = ht->nodes[hashval];
+
+    /* if no nodes at this hash value, return NULL */
+    if (!hp)
+	return NULL;
+
+    /* else check if the key in the first one matches */
+    if (ht->cmpnodes(hp->nam, nam) == 0) {
+	ht->nodes[hashval] = hp->next;
+	gotit:
+	ht->ct--;
+	if(ht->scan) {
+	    if(ht->scan->sorted) {
+		HashNode *tab = ht->scan->u.s.tab;
+		int i;
+		for(i = ht->scan->u.s.ct; i--; )
+		    if(tab[i] == hp)
+			tab[i] = NULL;
+	    } else if(ht->scan->u.u == hp)
+		ht->scan->u.u = hp->next;
+	}
+	return hp;
+    }
+
+    /* else run through the list and check the rest of the keys */
+    hq = hp;
+    hp = hp->next;
+    for (; hp; hq = hp, hp = hp->next) {
+	if (ht->cmpnodes(hp->nam, nam) == 0) {
+	    hq->next = hp->next;
+	    goto gotit;
+	}
+    }
+
+    /* else it is not in the list, so return NULL */
+    return NULL;
+}
+
+/* Disable a node in a hash table */
+
+/**/
+void
+disablehashnode(HashNode hn, UNUSED(int flags))
+{
+    hn->flags |= DISABLED;
+}
+
+/* Enable a node in a hash table */
+
+/**/
+void
+enablehashnode(HashNode hn, UNUSED(int flags))
+{
+    hn->flags &= ~DISABLED;
+}
+
+/* Compare two hash table entries by name */
+
+/**/
+static int
+hnamcmp(const void *ap, const void *bp)
+{
+    HashNode a = *(HashNode *)ap;
+    HashNode b = *(HashNode *)bp;
+    return ztrcmp((unsigned char *) a->nam, (unsigned char *) b->nam);
+}
+
+/* Scan the nodes in a hash table and execute scanfunc on nodes based on
+ * the flags that are set/unset.  scanflags is passed unchanged to
+ * scanfunc (if executed).
+ *
+ * If sorted != 0, then sort entries of hash table before scanning.
+ * If flags1 > 0, then execute scanfunc on a node only if at least one of
+ *                these flags is set.
+ * If flags2 > 0, then execute scanfunc on a node only if all of
+ *                these flags are NOT set.
+ * The conditions above for flags1/flags2 must both be true.
+ *
+ * It is safe to add, remove or replace hash table elements from within
+ * the scanfunc.  Replaced elements will appear in the scan exactly once,
+ * the new version if it was not scanned before the replacement was made.
+ * Added elements might or might not appear in the scan.
+ */
+
+/**/
+mod_export void
+scanhashtable(HashTable ht, int sorted, int flags1, int flags2, ScanFunc scanfunc, int scanflags)
+{
+    struct scanstatus st;
+
+    if (ht->scantab) {
+	ht->scantab(ht, scanfunc, scanflags);
+	return;
+    }
+    if (sorted) {
+	int i, ct = ht->ct;
+	VARARR(HashNode, hnsorttab, ct);
+	HashNode *htp, hn;
+
+	for (htp = hnsorttab, i = 0; i < ht->hsize; i++)
+	    for (hn = ht->nodes[i]; hn; hn = hn->next)
+		*htp++ = hn;
+	qsort((void *)hnsorttab, ct, sizeof(HashNode), hnamcmp);
+
+	st.sorted = 1;
+	st.u.s.tab = hnsorttab;
+	st.u.s.ct = ct;
+	ht->scan = &st;
+
+	for (htp = hnsorttab, i = 0; i < ct; i++, htp++)
+	    if (*htp && ((*htp)->flags & flags1) + !flags1 &&
+		!((*htp)->flags & flags2))
+		scanfunc(*htp, scanflags);
+
+	ht->scan = NULL;
+    } else {
+	int i, hsize = ht->hsize;
+	HashNode *nodes = ht->nodes;
+
+	st.sorted = 0;
+	ht->scan = &st;
+
+	for (i = 0; i < hsize; i++)
+	    for (st.u.u = nodes[i]; st.u.u; ) {
+		HashNode hn = st.u.u;
+		st.u.u = st.u.u->next;
+		if ((hn->flags & flags1) + !flags1 && !(hn->flags & flags2))
+		    scanfunc(hn, scanflags);
+	    }
+
+	ht->scan = NULL;
+    }
+}
+
+/* Scan all nodes in a hash table and executes scanfunc on the *
+ * nodes which meet all the following criteria:                *
+ * The hash key must match the glob pattern given by `com'.    *
+ * If (flags1 > 0), then any flag in flags1 must be set.       *
+ * If (flags2 > 0), then all flags in flags2 must NOT be set.  *
+ *                                                             *
+ * scanflags is passed unchanged to scanfunc (if executed).    *
+ * The return value is the number of matches.                  */
+
+/**/
+int
+scanmatchtable(HashTable ht, Patprog pprog, int flags1, int flags2, ScanFunc scanfunc, int scanflags)
+{
+    int i, hsize = ht->hsize;
+    HashNode *nodes = ht->nodes;
+    int match = 0;
+    struct scanstatus st;
+
+    st.sorted = 0;
+    ht->scan = &st;
+
+    for (i = 0; i < hsize; i++)
+	for (st.u.u = nodes[i]; st.u.u; ) {
+	    HashNode hn = st.u.u;
+	    st.u.u = st.u.u->next;
+	    if ((hn->flags & flags1) + !flags1 && !(hn->flags & flags2) &&
+		pattry(pprog, hn->nam)) {
+		scanfunc(hn, scanflags);
+		match++;
+	    }
+	}
+
+    ht->scan = NULL;
+
+    return match;
+}
+
+/* Expand hash tables when they get too many entries. *
+ * The new size is 4 times the previous size.         */
+
+/**/
+static void
+expandhashtable(HashTable ht)
+{
+    struct hashnode **onodes, **ha, *hn, *hp;
+    int i, osize;
+
+    osize = ht->hsize;
+    onodes = ht->nodes;
+
+    ht->hsize = osize * 4;
+    ht->nodes = (HashNode *) zshcalloc(ht->hsize * sizeof(HashNode));
+    ht->ct = 0;
+
+    /* scan through the old list of nodes, and *
+     * rehash them into the new list of nodes  */
+    for (i = 0, ha = onodes; i < osize; i++, ha++) {
+	for (hn = *ha; hn;) {
+	    hp = hn->next;
+	    ht->addnode(ht, hn->nam, hn);
+	    hn = hp;
+	}
+    }
+    zfree(onodes, osize * sizeof(HashNode));
+}
+
+/* Empty the hash table and resize it if necessary */
+
+/**/
+static void
+resizehashtable(HashTable ht, int newsize)
+{
+    struct hashnode **ha, *hn, *hp;
+    int i;
+
+    /* free all the hash nodes */
+    ha = ht->nodes;
+    for (i = 0; i < ht->hsize; i++, ha++) {
+	for (hn = *ha; hn;) {
+	    hp = hn->next;
+	    ht->freenode(hn);
+	    hn = hp;
+	}
+    }
+
+    /* If new size desired is different from current size, *
+     * we free it and allocate a new nodes array.          */
+    if (ht->hsize != newsize) {
+	zfree(ht->nodes, ht->hsize * sizeof(HashNode));
+	ht->nodes = (HashNode *) zshcalloc(newsize * sizeof(HashNode));
+	ht->hsize = newsize;
+    } else {
+	/* else we just re-zero the current nodes array */
+	memset(ht->nodes, 0, newsize * sizeof(HashNode));
+    }
+
+    ht->ct = 0;
+}
+
+/* Generic method to empty a hash table */
+
+/**/
+mod_export void
+emptyhashtable(HashTable ht)
+{
+    resizehashtable(ht, ht->hsize);
+}
+
+/**/
+#ifdef ZSH_HASH_DEBUG
+
+/* Print info about hash table */
+
+#define MAXDEPTH 7
+
+/**/
+static void
+printhashtabinfo(HashTable ht)
+{
+    HashNode hn;
+    int chainlen[MAXDEPTH + 1];
+    int i, tmpcount, total;
+
+    printf("name of table   : %s\n",   ht->tablename);
+    printf("size of nodes[] : %d\n",   ht->hsize);
+    printf("number of nodes : %d\n\n", ht->ct);
+
+    memset(chainlen, 0, sizeof(chainlen));
+
+    /* count the number of nodes just to be sure */
+    total = 0;
+    for (i = 0; i < ht->hsize; i++) {
+	tmpcount = 0;
+	for (hn = ht->nodes[i]; hn; hn = hn->next)
+	    tmpcount++;
+	if (tmpcount >= MAXDEPTH)
+	    chainlen[MAXDEPTH]++;
+	else
+	    chainlen[tmpcount]++;
+	total += tmpcount;
+    }
+
+    for (i = 0; i < MAXDEPTH; i++)
+	printf("number of hash values with chain of length %d  : %4d\n", i, chainlen[i]);
+    printf("number of hash values with chain of length %d+ : %4d\n", MAXDEPTH, chainlen[MAXDEPTH]);
+    printf("total number of nodes                         : %4d\n", total);
+}
+
+/**/
+int
+bin_hashinfo(char *nam, char **args, Options ops, int func)
+{
+    HashTable ht;
+
+    printf("----------------------------------------------------\n");
+    queue_signals();
+    for(ht = firstht; ht; ht = ht->next) {
+	ht->printinfo(ht);
+	printf("----------------------------------------------------\n");
+    }
+    unqueue_signals();
+    return 0;
+}
+
+/**/
+#endif /* ZSH_HASH_DEBUG */
+
+/********************************/
+/* Command Hash Table Functions */
+/********************************/
+
+/* hash table containing external commands */
+ 
+/**/
+mod_export HashTable cmdnamtab;
+ 
+/* how far we've hashed the PATH so far */
+ 
+/**/
+mod_export char **pathchecked;
+ 
+/* Create a new command hash table */
+ 
+/**/
+void
+createcmdnamtable(void)
+{
+    cmdnamtab = newhashtable(201, "cmdnamtab", NULL);
+
+    cmdnamtab->hash        = hasher;
+    cmdnamtab->emptytable  = emptycmdnamtable;
+    cmdnamtab->filltable   = fillcmdnamtable;
+    cmdnamtab->cmpnodes    = strcmp;
+    cmdnamtab->addnode     = addhashnode;
+    cmdnamtab->getnode     = gethashnode2;
+    cmdnamtab->getnode2    = gethashnode2;
+    cmdnamtab->removenode  = removehashnode;
+    cmdnamtab->disablenode = NULL;
+    cmdnamtab->enablenode  = NULL;
+    cmdnamtab->freenode    = freecmdnamnode;
+    cmdnamtab->printnode   = printcmdnamnode;
+
+    pathchecked = path;
+}
+
+/**/
+static void
+emptycmdnamtable(HashTable ht)
+{
+    emptyhashtable(ht);
+    pathchecked = path;
+}
+
+/* Add all commands in a given directory *
+ * to the command hashtable.             */
+
+/**/
+void
+hashdir(char **dirp)
+{
+    Cmdnam cn;
+    DIR *dir;
+    char *fn;
+#if defined(_WIN32) || defined(__CYGWIN__)
+    char *exe;
+#endif /* _WIN32 || _CYGWIN__ */
+
+    if (isrelative(*dirp) || !(dir = opendir(unmeta(*dirp))))
+	return;
+
+    while ((fn = zreaddir(dir, 1))) {
+	if (!cmdnamtab->getnode(cmdnamtab, fn)) {
+	    cn = (Cmdnam) zshcalloc(sizeof *cn);
+	    cn->flags = 0;
+	    cn->u.name = dirp;
+	    cmdnamtab->addnode(cmdnamtab, ztrdup(fn), cn);
+	}
+#if defined(_WIN32) || defined(__CYGWIN__)
+	/* Hash foo.exe as foo, since when no real foo exists, foo.exe
+	   will get executed by DOS automatically.  This quiets
+	   spurious corrections when CORRECT or CORRECT_ALL is set. */
+	if ((exe = strrchr(fn, '.')) &&
+	    (exe[1] == 'E' || exe[1] == 'e') &&
+	    (exe[2] == 'X' || exe[2] == 'x') &&
+	    (exe[3] == 'E' || exe[3] == 'e') && exe[4] == 0) {
+	    *exe = 0;
+	    if (!cmdnamtab->getnode(cmdnamtab, fn)) {
+		cn = (Cmdnam) zshcalloc(sizeof *cn);
+		cn->flags = 0;
+		cn->u.name = dirp;
+		cmdnamtab->addnode(cmdnamtab, ztrdup(fn), cn);
+	    }
+	}
+#endif /* _WIN32 || __CYGWIN__ */
+    }
+    closedir(dir);
+}
+
+/* Go through user's PATH and add everything to *
+ * the command hashtable.                       */
+
+/**/
+static void
+fillcmdnamtable(UNUSED(HashTable ht))
+{
+    char **pq;
+ 
+    for (pq = pathchecked; *pq; pq++)
+	hashdir(pq);
+
+    pathchecked = pq;
+}
+
+/**/
+static void
+freecmdnamnode(HashNode hn)
+{
+    Cmdnam cn = (Cmdnam) hn;
+ 
+    zsfree(cn->nam);
+    if (cn->flags & HASHED)
+	zsfree(cn->u.cmd);
+ 
+    zfree(cn, sizeof(struct cmdnam));
+}
+
+/* Print an element of the cmdnamtab hash table (external command) */
+ 
+/**/
+static void
+printcmdnamnode(HashNode hn, int printflags)
+{
+    Cmdnam cn = (Cmdnam) hn;
+
+    if (printflags & PRINT_WHENCE_WORD) {
+	printf("%s: %s\n", cn->nam, (cn->flags & HASHED) ? 
+	       "hashed" : "command");
+	return;
+    }
+
+    if ((printflags & PRINT_WHENCE_CSH) || (printflags & PRINT_WHENCE_SIMPLE)) {
+	if (cn->flags & HASHED) {
+	    zputs(cn->u.cmd, stdout);
+	    putchar('\n');
+	} else {
+	    zputs(*(cn->u.name), stdout);
+	    putchar('/');
+	    zputs(cn->nam, stdout);
+	    putchar('\n');
+	}
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_VERBOSE) {
+	if (cn->flags & HASHED) {
+	    nicezputs(cn->nam, stdout);
+	    printf(" is hashed to ");
+	    nicezputs(cn->u.cmd, stdout);
+	    putchar('\n');
+	} else {
+	    nicezputs(cn->nam, stdout);
+	    printf(" is ");
+	    nicezputs(*(cn->u.name), stdout);
+	    putchar('/');
+	    nicezputs(cn->nam, stdout);
+	    putchar('\n');
+	}
+	return;
+    }
+
+    if (printflags & PRINT_LIST) {
+	printf("hash ");
+
+	if(cn->nam[0] == '-')
+	    printf("-- ");
+    }
+
+    if (cn->flags & HASHED) {
+	quotedzputs(cn->nam, stdout);
+	putchar('=');
+	quotedzputs(cn->u.cmd, stdout);
+	putchar('\n');
+    } else {
+	quotedzputs(cn->nam, stdout);
+	putchar('=');
+	quotedzputs(*(cn->u.name), stdout);
+	putchar('/');
+	quotedzputs(cn->nam, stdout);
+	putchar('\n');
+    }
+}
+
+/***************************************/
+/* Shell Function Hash Table Functions */
+/***************************************/
+
+/* hash table containing the shell functions */
+
+/**/
+mod_export HashTable shfunctab;
+
+/**/
+void
+createshfunctable(void)
+{
+    shfunctab = newhashtable(7, "shfunctab", NULL);
+
+    shfunctab->hash        = hasher;
+    shfunctab->emptytable  = NULL;
+    shfunctab->filltable   = NULL;
+    shfunctab->cmpnodes    = strcmp;
+    shfunctab->addnode     = addhashnode;
+    shfunctab->getnode     = gethashnode;
+    shfunctab->getnode2    = gethashnode2;
+    shfunctab->removenode  = removeshfuncnode;
+    shfunctab->disablenode = disableshfuncnode;
+    shfunctab->enablenode  = enableshfuncnode;
+    shfunctab->freenode    = freeshfuncnode;
+    shfunctab->printnode   = printshfuncnode;
+}
+
+/* Remove an entry from the shell function hash table.   *
+ * It checks if the function is a signal trap and if so, *
+ * it will disable the trapping of that signal.          */
+
+/**/
+static HashNode
+removeshfuncnode(UNUSED(HashTable ht), char *nam)
+{
+    HashNode hn;
+    int signum;
+
+    if (!strncmp(nam, "TRAP", 4) && (signum = getsignum(nam + 4)) != -1)
+	hn = removetrap(signum);
+    else
+	hn = removehashnode(shfunctab, nam);
+
+    return hn;
+}
+
+/* Disable an entry in the shell function hash table.    *
+ * It checks if the function is a signal trap and if so, *
+ * it will disable the trapping of that signal.          */
+
+/**/
+static void
+disableshfuncnode(HashNode hn, UNUSED(int flags))
+{
+    hn->flags |= DISABLED;
+    if (!strncmp(hn->nam, "TRAP", 4)) {
+	int signum = getsignum(hn->nam + 4);
+	sigtrapped[signum] &= ~ZSIG_FUNC;
+	sigfuncs[signum] = NULL;
+	unsettrap(signum);
+    }
+}
+
+/* Re-enable an entry in the shell function hash table.  *
+ * It checks if the function is a signal trap and if so, *
+ * it will re-enable the trapping of that signal.        */
+
+/**/
+static void
+enableshfuncnode(HashNode hn, UNUSED(int flags))
+{
+    Shfunc shf = (Shfunc) hn;
+
+    shf->flags &= ~DISABLED;
+    if (!strncmp(shf->nam, "TRAP", 4)) {
+	int signum = getsignum(shf->nam + 4);
+	if (signum != -1) {
+	    settrap(signum, shf->funcdef);
+	    sigtrapped[signum] |= ZSIG_FUNC;
+	}
+    }
+}
+
+/**/
+static void
+freeshfuncnode(HashNode hn)
+{
+    Shfunc shf = (Shfunc) hn;
+
+    zsfree(shf->nam);
+    if (shf->funcdef)
+	freeeprog(shf->funcdef);
+    zfree(shf, sizeof(struct shfunc));
+}
+
+/* Print a shell function */
+ 
+/**/
+static void
+printshfuncnode(HashNode hn, int printflags)
+{
+    Shfunc f = (Shfunc) hn;
+    char *t = 0;
+ 
+    if ((printflags & PRINT_NAMEONLY) ||
+	((printflags & PRINT_WHENCE_SIMPLE) &&
+	!(printflags & PRINT_WHENCE_FUNCDEF))) {
+	zputs(f->nam, stdout);
+	putchar('\n');
+	return;
+    }
+ 
+    if ((printflags & (PRINT_WHENCE_VERBOSE|PRINT_WHENCE_WORD)) &&
+	!(printflags & PRINT_WHENCE_FUNCDEF)) {
+	nicezputs(f->nam, stdout);
+	printf((printflags & PRINT_WHENCE_WORD) ? ": function\n" :
+	       " is a shell function\n");
+	return;
+    }
+ 
+    quotedzputs(f->nam, stdout);
+    if (f->funcdef || f->flags & PM_UNDEFINED) {
+	printf(" () {\n\t");
+	if (f->flags & PM_UNDEFINED)
+	    printf("%c undefined\n\t", hashchar);
+	else
+	    t = getpermtext(f->funcdef, NULL);
+	if (f->flags & PM_TAGGED)
+	    printf("%c traced\n\t", hashchar);
+	if (!t) {
+	    char *fopt = "Utkz";
+	    int flgs[] = {
+		PM_UNALIASED, PM_TAGGED, PM_KSHSTORED, PM_ZSHSTORED, 0
+	    };
+	    int fl;;
+
+	    zputs("builtin autoload -X", stdout);
+	    for (fl=0;fopt[fl];fl++)
+		if (f->flags & flgs[fl]) putchar(fopt[fl]);
+	} else {
+	    zputs(t, stdout);
+	    zsfree(t);
+	    if (f->funcdef->flags & EF_RUN) {
+		printf("\n\t");
+		quotedzputs(f->nam, stdout);
+		printf(" \"$@\"");
+	    }
+	}   
+	printf("\n}\n");
+    } else {
+	printf(" () { }\n");
+    }
+}
+
+/**************************************/
+/* Reserved Word Hash Table Functions */
+/**************************************/
+
+/* Nodes for reserved word hash table */
+
+static struct reswd reswds[] = {
+    {NULL, "!", 0, BANG},
+    {NULL, "[[", 0, DINBRACK},
+    {NULL, "{", 0, INBRACE},
+    {NULL, "}", 0, OUTBRACE},
+    {NULL, "case", 0, CASE},
+    {NULL, "coproc", 0, COPROC},
+    {NULL, "do", 0, DOLOOP},
+    {NULL, "done", 0, DONE},
+    {NULL, "elif", 0, ELIF},
+    {NULL, "else", 0, ELSE},
+    {NULL, "end", 0, ZEND},
+    {NULL, "esac", 0, ESAC},
+    {NULL, "fi", 0, FI},
+    {NULL, "for", 0, FOR},
+    {NULL, "foreach", 0, FOREACH},
+    {NULL, "function", 0, FUNC},
+    {NULL, "if", 0, IF},
+    {NULL, "nocorrect", 0, NOCORRECT},
+    {NULL, "repeat", 0, REPEAT},
+    {NULL, "select", 0, SELECT},
+    {NULL, "then", 0, THEN},
+    {NULL, "time", 0, TIME},
+    {NULL, "until", 0, UNTIL},
+    {NULL, "while", 0, WHILE},
+    {NULL, NULL, 0, 0}
+};
+
+/* hash table containing the reserved words */
+
+/**/
+mod_export HashTable reswdtab;
+
+/* Build the hash table containing zsh's reserved words. */
+
+/**/
+void
+createreswdtable(void)
+{
+    Reswd rw;
+
+    reswdtab = newhashtable(23, "reswdtab", NULL);
+
+    reswdtab->hash        = hasher;
+    reswdtab->emptytable  = NULL;
+    reswdtab->filltable   = NULL;
+    reswdtab->cmpnodes    = strcmp;
+    reswdtab->addnode     = addhashnode;
+    reswdtab->getnode     = gethashnode;
+    reswdtab->getnode2    = gethashnode2;
+    reswdtab->removenode  = NULL;
+    reswdtab->disablenode = disablehashnode;
+    reswdtab->enablenode  = enablehashnode;
+    reswdtab->freenode    = NULL;
+    reswdtab->printnode   = printreswdnode;
+
+    for (rw = reswds; rw->nam; rw++)
+	reswdtab->addnode(reswdtab, rw->nam, rw);
+}
+
+/* Print a reserved word */
+
+/**/
+static void
+printreswdnode(HashNode hn, int printflags)
+{
+    Reswd rw = (Reswd) hn;
+
+    if (printflags & PRINT_WHENCE_WORD) {
+	printf("%s: reserved\n", rw->nam);
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_CSH) {
+	printf("%s: shell reserved word\n", rw->nam);
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_VERBOSE) {
+	printf("%s is a reserved word\n", rw->nam);
+	return;
+    }
+
+    /* default is name only */
+    printf("%s\n", rw->nam);
+}
+
+/********************************/
+/* Aliases Hash Table Functions */
+/********************************/
+
+/* hash table containing the aliases */
+ 
+/**/
+mod_export HashTable aliastab;
+ 
+/* has table containing suffix aliases */
+
+/**/
+mod_export HashTable sufaliastab;
+ 
+/* Create new hash tables for aliases */
+
+/**/
+void
+createaliastable(HashTable ht)
+{
+    ht->hash        = hasher;
+    ht->emptytable  = NULL;
+    ht->filltable   = NULL;
+    ht->cmpnodes    = strcmp;
+    ht->addnode     = addhashnode;
+    ht->getnode     = gethashnode;
+    ht->getnode2    = gethashnode2;
+    ht->removenode  = removehashnode;
+    ht->disablenode = disablehashnode;
+    ht->enablenode  = enablehashnode;
+    ht->freenode    = freealiasnode;
+    ht->printnode   = printaliasnode;
+}
+
+/**/
+void
+createaliastables(void)
+{
+    /* Table for regular and global aliases */
+
+    aliastab = newhashtable(23, "aliastab", NULL);
+
+    createaliastable(aliastab);
+
+    /* add the default aliases */
+    aliastab->addnode(aliastab, ztrdup("run-help"), createaliasnode(ztrdup("man"), 0));
+    aliastab->addnode(aliastab, ztrdup("which-command"), createaliasnode(ztrdup("whence"), 0));
+
+
+    /* Table for suffix aliases --- make this smaller */
+
+    sufaliastab = newhashtable(11, "sufaliastab", NULL);
+
+    createaliastable(sufaliastab);
+}
+
+/* Create a new alias node */
+
+/**/
+mod_export Alias
+createaliasnode(char *txt, int flags)
+{
+    Alias al;
+
+    al = (Alias) zshcalloc(sizeof *al);
+    al->flags = flags;
+    al->text = txt;
+    al->inuse = 0;
+    return al;
+}
+
+/**/
+static void
+freealiasnode(HashNode hn)
+{
+    Alias al = (Alias) hn;
+ 
+    zsfree(al->nam);
+    zsfree(al->text);
+    zfree(al, sizeof(struct alias));
+}
+
+/* Print an alias */
+
+/**/
+static void
+printaliasnode(HashNode hn, int printflags)
+{
+    Alias a = (Alias) hn;
+
+    if (printflags & PRINT_NAMEONLY) {
+	zputs(a->nam, stdout);
+	putchar('\n');
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_WORD) {
+	printf("%s: alias\n", a->nam);
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_SIMPLE) {
+	zputs(a->text, stdout);
+	putchar('\n');
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_CSH) {
+	nicezputs(a->nam, stdout);
+	printf(": ");
+	if (a->flags & ALIAS_SUFFIX)
+	    printf("suffix ");
+	else if (a->flags & ALIAS_GLOBAL)
+	    printf("globally ");
+	printf ("aliased to ");
+	nicezputs(a->text, stdout);
+	putchar('\n');
+	return;
+    }
+
+    if (printflags & PRINT_WHENCE_VERBOSE) {
+	nicezputs(a->nam, stdout);
+	printf(" is a");
+	if (a->flags & ALIAS_SUFFIX)
+	    printf(" suffix");
+	else if (a->flags & ALIAS_GLOBAL)
+	    printf(" global");
+	else
+	    printf("n");
+	printf(" alias for ");
+	nicezputs(a->text, stdout);
+	putchar('\n');
+	return;
+    }
+
+    if (printflags & PRINT_LIST) {
+	printf("alias ");
+	if (a->flags & ALIAS_SUFFIX)
+	    printf("-s ");
+	else if (a->flags & ALIAS_GLOBAL)
+	    printf("-g ");
+
+	/* If an alias begins with `-', then we must output `-- ' *
+	 * first, so that it is not interpreted as an option.     */
+	if(a->nam[0] == '-')
+	    printf("-- ");
+    }
+
+    quotedzputs(a->nam, stdout);
+    putchar('=');
+    quotedzputs(a->text, stdout);
+
+    putchar('\n');
+}
+
+/****************************************/
+/* Named Directory Hash Table Functions */
+/****************************************/
+
+#ifdef HAVE_NIS_PLUS
+# include <rpcsvc/nis.h>
+#else
+# ifdef HAVE_NIS
+#  include	<rpc/types.h>
+#  include	<rpc/rpc.h>
+#  include	<rpcsvc/ypclnt.h>
+#  include	<rpcsvc/yp_prot.h>
+# endif
+#endif
+
+/* hash table containing named directories */
+
+/**/
+mod_export HashTable nameddirtab;
+ 
+/* != 0 if all the usernames have already been *
+ * added to the named directory hash table.    */
+
+static int allusersadded;
+
+/* Create new hash table for named directories */
+
+/**/
+void
+createnameddirtable(void)
+{
+    nameddirtab = newhashtable(201, "nameddirtab", NULL);
+
+    nameddirtab->hash        = hasher;
+    nameddirtab->emptytable  = emptynameddirtable;
+    nameddirtab->filltable   = fillnameddirtable;
+    nameddirtab->cmpnodes    = strcmp;
+    nameddirtab->addnode     = addnameddirnode;
+    nameddirtab->getnode     = gethashnode;
+    nameddirtab->getnode2    = gethashnode2;
+    nameddirtab->removenode  = removenameddirnode;
+    nameddirtab->disablenode = NULL;
+    nameddirtab->enablenode  = NULL;
+    nameddirtab->freenode    = freenameddirnode;
+    nameddirtab->printnode   = printnameddirnode;
+
+    allusersadded = 0;
+    finddir(NULL);		/* clear the finddir cache */
+}
+
+/* Empty the named directories table */
+
+/**/
+static void
+emptynameddirtable(HashTable ht)
+{
+    emptyhashtable(ht);
+    allusersadded = 0;
+    finddir(NULL);		/* clear the finddir cache */
+}
+
+/* Add all the usernames in the password file/database *
+ * to the named directories table.                     */
+
+#ifdef HAVE_NIS_PLUS
+static int
+add_userdir(nis_name table, nis_object *object, void *userdata)
+{
+    if (object->zo_data.objdata_u.en_data.en_cols.en_cols_len >= 6) {
+	static char name[40], dir[PATH_MAX + 1];
+	register entry_col *ec =
+	    object->zo_data.objdata_u.en_data.en_cols.en_cols_val;
+	register int nl = minimum(ec[0].ec_value.ec_value_len, 39);
+	register int dl = minimum(ec[5].ec_value.ec_value_len, PATH_MAX);
+
+	memcpy(name, ec[0].ec_value.ec_value_val, nl);
+	name[nl] = '\0';
+	memcpy(dir, ec[5].ec_value.ec_value_val, dl);
+	dir[dl] = '\0';
+
+	adduserdir(name, dir, ND_USERNAME, 1);
+    }
+    return 0;
+}
+#else
+# ifdef HAVE_NIS
+static int
+add_userdir(int status, char *key, int keylen, char *val, int vallen, char *dummy)
+{
+    char *p, *d, *de;
+
+    if (status != YP_TRUE)
+	return 1;
+
+    if (vallen > keylen && *(p = val + keylen) == ':') {
+	*p++ = '\0';
+	if ((de = strrchr(p, ':'))) {
+	    *de = '\0';
+	    if ((d = strrchr(p, ':'))) {
+		if (*++d && val[0])
+		    adduserdir(val, d, ND_USERNAME, 1);
+	    }
+	}
+    }
+    return 0;
+}
+# endif /* HAVE_NIS */
+#endif  /* HAVE_NIS_PLUS */
+
+/**/
+static void
+fillnameddirtable(UNUSED(HashTable ht))
+{
+    if (!allusersadded) {
+#if defined(HAVE_NIS) || defined(HAVE_NIS_PLUS)
+	FILE *pwf;
+	char buf[BUFSIZ], *p, *d, *de;
+	int skipping, oldct = nameddirtab->ct, usepwf = 1;
+
+# ifndef HAVE_NIS_PLUS
+	char domain[YPMAXDOMAIN];
+	struct ypall_callback cb;
+
+	/* Get potential matches from NIS and cull those without local accounts */
+	if (getdomainname(domain, YPMAXDOMAIN) == 0) {
+	    cb.foreach = (int (*)()) add_userdir;
+	    cb.data = NULL;
+	    yp_all(domain, PASSWD_MAP, &cb);
+    }
+# else  /* HAVE_NIS_PLUS */
+	/* Maybe we should turn this string into a #define'd constant...? */
+
+	nis_list("passwd.org_dir", EXPAND_NAME|ALL_RESULTS|FOLLOW_LINKS|FOLLOW_PATH,
+		 add_userdir, 0);
+# endif
+	if (nameddirtab->ct == oldct) {
+	    /* Using NIS or NIS+ didn't add any user directories. This seems
+	     * fishy, so we fall back to using getpwent(). If we don't have
+	     * that, we only use the passwd file. */
+#ifdef HAVE_GETPWENT
+	    struct passwd *pw;
+ 
+	    setpwent();
+ 
+	    /* loop through the password file/database *
+	     * and add all entries returned.           */
+	    while ((pw = getpwent()) && !errflag)
+		adduserdir(pw->pw_name, pw->pw_dir, ND_USERNAME, 1);
+ 
+	    endpwent();
+	    usepwf = 0;
+#endif /* HAVE_GETPWENT */
+	}
+	if (usepwf) {
+	    /* Don't forget the non-NIS matches from the flat passwd file */
+	    if ((pwf = fopen(PASSWD_FILE, "r")) != NULL) {
+		skipping = 0;
+		while (fgets(buf, BUFSIZ, pwf) != NULL) {
+		    if (strchr(buf, '\n') != NULL) {
+			if (!skipping) {
+			    if ((p = strchr(buf, ':')) != NULL) {
+				*p++ = '\0';
+				if ((de = strrchr(p, ':'))) {
+				    *de = '\0';
+				    if ((d = strrchr(p, ':'))) {
+					if (*++d && buf[0])
+					    adduserdir(buf, d, ND_USERNAME, 1);
+				    }
+				}
+			    }
+			} else
+			    skipping = 0;
+		    } else
+			skipping = 1;
+		}
+		fclose(pwf);
+	    }
+	}
+#else  /* no NIS or NIS_PLUS */
+#ifdef HAVE_GETPWENT
+	struct passwd *pw;
+ 
+	setpwent();
+ 
+	/* loop through the password file/database *
+	 * and add all entries returned.           */
+	while ((pw = getpwent()) && !errflag)
+	    adduserdir(pw->pw_name, pw->pw_dir, ND_USERNAME, 1);
+ 
+	endpwent();
+#endif /* HAVE_GETPWENT */
+#endif
+	allusersadded = 1;
+    }
+}
+
+/* Add an entry to the named directory hash *
+ * table, clearing the finddir() cache and  *
+ * initialising the `diff' member.          */
+
+/**/
+static void
+addnameddirnode(HashTable ht, char *nam, void *nodeptr)
+{
+    Nameddir nd = (Nameddir) nodeptr;
+
+    nd->diff = strlen(nd->dir) - strlen(nam);
+    finddir(NULL);		/* clear the finddir cache */
+    addhashnode(ht, nam, nodeptr);
+}
+
+/* Remove an entry from the named directory  *
+ * hash table, clearing the finddir() cache. */
+
+/**/
+static HashNode
+removenameddirnode(HashTable ht, char *nam)
+{
+    HashNode hn = removehashnode(ht, nam);
+
+    if(hn)
+	finddir(NULL);		/* clear the finddir cache */
+    return hn;
+}
+
+/* Free up the memory used by a named directory hash node. */
+
+/**/
+static void
+freenameddirnode(HashNode hn)
+{
+    Nameddir nd = (Nameddir) hn;
+ 
+    zsfree(nd->nam);
+    zsfree(nd->dir);
+    zfree(nd, sizeof(struct nameddir));
+}
+
+/* Print a named directory */
+
+/**/
+static void
+printnameddirnode(HashNode hn, int printflags)
+{
+    Nameddir nd = (Nameddir) hn;
+
+    if (printflags & PRINT_NAMEONLY) {
+	zputs(nd->nam, stdout);
+	putchar('\n');
+	return;
+    }
+    
+    if (printflags & PRINT_LIST) {
+      printf("hash -d ");
+
+      if(nd->nam[0] == '-')
+	    printf("-- ");
+    }
+
+    quotedzputs(nd->nam, stdout);
+    putchar('=');
+    quotedzputs(nd->dir, stdout);
+    putchar('\n');
+}
+
+/*************************************/
+/* History Line Hash Table Functions */
+/*************************************/
+
+/**/
+void
+createhisttable(void)
+{
+    histtab = newhashtable(599, "histtab", NULL);
+
+    histtab->hash        = histhasher;
+    histtab->emptytable  = emptyhisttable;
+    histtab->filltable   = NULL;
+    histtab->cmpnodes    = histstrcmp;
+    histtab->addnode     = addhistnode;
+    histtab->getnode     = gethashnode2;
+    histtab->getnode2    = gethashnode2;
+    histtab->removenode  = removehashnode;
+    histtab->disablenode = NULL;
+    histtab->enablenode  = NULL;
+    histtab->freenode    = freehistnode;
+    histtab->printnode   = NULL;
+}
+
+/**/
+unsigned
+histhasher(char *str)
+{
+    unsigned hashval = 0;
+
+    while (inblank(*str)) str++;
+
+    while (*str) {
+	if (inblank(*str)) {
+	    do str++; while (inblank(*str));
+	    if (*str)
+		hashval += (hashval << 5) + ' ';
+	}
+	else
+	    hashval += (hashval << 5) + *(unsigned char *)str++;
+    }
+    return hashval;
+}
+
+/**/
+void
+emptyhisttable(HashTable ht)
+{
+    emptyhashtable(ht);
+    if (hist_ring)
+	histremovedups();
+}
+
+/* Compare two strings with normalized white-space */
+
+/**/
+int
+histstrcmp(const char *str1, const char *str2)
+{
+    while (inblank(*str1)) str1++;
+    while (inblank(*str2)) str2++;
+    while (*str1 && *str2) {
+	if (inblank(*str1)) {
+	    if (!inblank(*str2))
+		break;
+	    do str1++; while (inblank(*str1));
+	    do str2++; while (inblank(*str2));
+	}
+	else {
+	    if (*str1 != *str2)
+		break;
+	    str1++;
+	    str2++;
+	}
+    }
+    return *str1 - *str2;
+}
+
+/**/
+void
+addhistnode(HashTable ht, char *nam, void *nodeptr)
+{
+    HashNode oldnode = addhashnode2(ht, nam, nodeptr);
+    Histent he = (Histent)nodeptr;
+    if (oldnode && oldnode != (HashNode)nodeptr) {
+	if (he->flags & HIST_MAKEUNIQUE
+	 || (he->flags & HIST_FOREIGN && (Histent)oldnode == he->up)) {
+	    (void) addhashnode2(ht, oldnode->nam, oldnode); /* restore hash */
+	    he->flags |= HIST_DUP;
+	    he->flags &= ~HIST_MAKEUNIQUE;
+	}
+	else {
+	    oldnode->flags |= HIST_DUP;
+	    if (hist_ignore_all_dups)
+		freehistnode(oldnode); /* Remove the old dup */
+	}
+    }
+    else
+	he->flags &= ~HIST_MAKEUNIQUE;
+}
+
+/**/
+void
+freehistnode(HashNode nodeptr)
+{
+    freehistdata((Histent)nodeptr, 1);
+    zfree(nodeptr, sizeof (struct histent));
+}
+
+/**/
+void
+freehistdata(Histent he, int unlink)
+{
+    if (!he)
+	return;
+
+    if (!(he->flags & (HIST_DUP | HIST_TMPSTORE)))
+	removehashnode(histtab, he->text);
+
+    zsfree(he->text);
+    if (he->nwords)
+	zfree(he->words, he->nwords*2*sizeof(short));
+
+    if (unlink) {
+	if (!--histlinect)
+	    hist_ring = NULL;
+	else {
+	    if (he == hist_ring)
+		hist_ring = hist_ring->up;
+	    he->up->down = he->down;
+	    he->down->up = he->up;
+	}
+    }
+}