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diff --git a/cddl/contrib/opensolaris/cmd/sgs/tools/common/string_table.c b/cddl/contrib/opensolaris/cmd/sgs/tools/common/string_table.c
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+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident "%Z%%M% %I% %E% SMI"
+
+#include <_string_table.h>
+#include <strings.h>
+#include <sgs.h>
+#include <stdio.h>
+
+/*
+ * This file provides the interfaces to build a Str_tbl suitable for use by
+ * either the sgsmsg message system, or a standard ELF string table (SHT_STRTAB)
+ * as created by ld(1).
+ *
+ * There are two modes which can be used when constructing a string table:
+ *
+ * st_new(0)
+ * standard string table - no compression. This is the
+ * traditional, fast method.
+ *
+ * st_new(FLG_STTAB_COMPRESS)
+ * builds a compressed string table which both eliminates
+ * duplicate strings, and permits strings with common suffixes
+ * (atexit vs. exit) to overlap in the table. This provides space
+ * savings for many string tables. Although more work than the
+ * traditional method, the algorithms used are designed to scale
+ * and keep any overhead at a minimum.
+ *
+ * These string tables are built with a common interface in a two-pass manner.
+ * The first pass finds all of the strings required for the string-table and
+ * calculates the size required for the final string table.
+ *
+ * The second pass allocates the string table, populates the strings into the
+ * table and returns the offsets the strings have been assigned.
+ *
+ * The calling sequence to build and populate a string table is:
+ *
+ * st_new(); // initialize strtab
+ *
+ * st_insert(st1); // first pass of strings ...
+ * // calculates size required for
+ * // string table
+ *
+ * st_delstring(st?); // remove string previously
+ * // inserted
+ * st_insert(stN);
+ *
+ * st_getstrtab_sz(); // freezes strtab and computes
+ * // size of table.
+ *
+ * st_setstrbuf(); // associates a final destination
+ * // for the string table
+ *
+ * st_setstring(st1); // populate the string table
+ * ... // offsets are based off of second
+ * // pass through the string table
+ * st_setstring(stN);
+ *
+ * st_destroy(); // tear down string table
+ * // structures.
+ *
+ * String Suffix Compression Algorithm:
+ *
+ * Here's a quick high level overview of the Suffix String
+ * compression algorithm used. First - the heart of the algorithm
+ * is a Hash table list which represents a dictionary of all unique
+ * strings inserted into the string table. The hash function for
+ * this table is a standard string hash except that the hash starts
+ * at the last character in the string (&str[n - 1]) and works towards
+ * the first character in the function (&str[0]). As we compute the
+ * HASH value for a given string, we also compute the hash values
+ * for all of the possible suffix strings for that string.
+ *
+ * As we compute the hash - at each character see if the current
+ * suffix string for that hash is already present in the table. If
+ * it is, and the string is a master string. Then change that
+ * string to a suffix string of the new string being inserted.
+ *
+ * When the final hash value is found (hash for str[0...n]), check
+ * to see if it is in the hash table - if so increment the reference
+ * count for the string. If it is not yet in the table, insert a
+ * new hash table entry for a master string.
+ *
+ * The above method will find all suffixes of a given string given
+ * that the strings are inserted from shortest to longest. That is
+ * why this is a two phase method, we first collect all of the
+ * strings and store them based off of their length in an AVL tree.
+ * Once all of the strings have been submitted we then start the
+ * hash table build by traversing the AVL tree in order and
+ * inserting the strings from shortest to longest as described
+ * above.
+ */
+
+/* LINTLIBRARY */
+
+static int
+avl_len_compare(const void *n1, const void *n2)
+{
+ size_t len1, len2;
+
+ len1 = ((LenNode *)n1)->ln_strlen;
+ len2 = ((LenNode *)n2)->ln_strlen;
+
+ if (len1 == len2)
+ return (0);
+ if (len2 < len1)
+ return (1);
+ return (-1);
+}
+
+static int
+avl_str_compare(const void *n1, const void *n2)
+{
+ const char *str1, *str2;
+ int rc;
+
+ str1 = ((StrNode *)n1)->sn_str;
+ str2 = ((StrNode *)n2)->sn_str;
+
+ rc = strcmp(str1, str2);
+ if (rc > 0)
+ return (1);
+ if (rc < 0)
+ return (-1);
+ return (0);
+}
+
+/*
+ * Return an initialized Str_tbl - returns NULL on failure.
+ *
+ * flags:
+ * FLG_STTAB_COMPRESS - build a compressed string table
+ */
+Str_tbl *
+st_new(uint_t flags)
+{
+ Str_tbl *stp;
+
+ if ((stp = calloc(sizeof (Str_tbl), 1)) == NULL)
+ return (NULL);
+
+ /*
+ * Start with a leading '\0' - it's tradition.
+ */
+ stp->st_strsize = stp->st_fullstrsize = stp->st_nextoff = 1;
+
+ /*
+ * Do we compress this string table?
+ */
+ stp->st_flags = flags;
+ if ((stp->st_flags & FLG_STTAB_COMPRESS) == 0)
+ return (stp);
+
+ if ((stp->st_lentree = calloc(sizeof (avl_tree_t), 1)) == NULL)
+ return (NULL);
+
+ avl_create(stp->st_lentree, &avl_len_compare, sizeof (LenNode),
+ SGSOFFSETOF(LenNode, ln_avlnode));
+
+ return (stp);
+}
+
+/*
+ * Insert a new string into the Str_tbl. There are two AVL trees used.
+ *
+ * . The first LenNode AVL tree maintains a tree of nodes based on string
+ * sizes.
+ * . Each LenNode maintains a StrNode AVL tree for each string. Large
+ * applications have been known to contribute thousands of strings of
+ * the same size. Should strings need to be removed (-z ignore), then
+ * the string AVL tree makes this removal efficient and scalable.
+ */
+int
+st_insert(Str_tbl *stp, const char *str)
+{
+ size_t len;
+ StrNode *snp, sn = { 0 };
+ LenNode *lnp, ln = { 0 };
+ avl_index_t where;
+
+ /*
+ * String table can't have been cooked
+ */
+ assert((stp->st_flags & FLG_STTAB_COOKED) == 0);
+
+ /*
+ * Null strings always point to the head of the string
+ * table - no reason to keep searching.
+ */
+ if ((len = strlen(str)) == 0)
+ return (0);
+
+ stp->st_fullstrsize += len + 1;
+ stp->st_strcnt++;
+
+ if ((stp->st_flags & FLG_STTAB_COMPRESS) == 0)
+ return (0);
+
+ /*
+ * From the controlling string table, determine which LenNode AVL node
+ * provides for this string length. If the node doesn't exist, insert
+ * a new node to represent this string length.
+ */
+ ln.ln_strlen = len;
+ if ((lnp = avl_find(stp->st_lentree, &ln, &where)) == NULL) {
+ if ((lnp = calloc(sizeof (LenNode), 1)) == NULL)
+ return (-1);
+ lnp->ln_strlen = len;
+ avl_insert(stp->st_lentree, lnp, where);
+
+ if ((lnp->ln_strtree = calloc(sizeof (avl_tree_t), 1)) == NULL)
+ return (0);
+
+ avl_create(lnp->ln_strtree, &avl_str_compare, sizeof (StrNode),
+ SGSOFFSETOF(StrNode, sn_avlnode));
+ }
+
+ /*
+ * From the string length AVL node determine whether a StrNode AVL node
+ * provides this string. If the node doesn't exist, insert a new node
+ * to represent this string.
+ */
+ sn.sn_str = str;
+ if ((snp = avl_find(lnp->ln_strtree, &sn, &where)) == NULL) {
+ if ((snp = calloc(sizeof (StrNode), 1)) == NULL)
+ return (-1);
+ snp->sn_str = str;
+ avl_insert(lnp->ln_strtree, snp, where);
+ }
+ snp->sn_refcnt++;
+
+ return (0);
+}
+
+/*
+ * Remove a previously inserted string from the Str_tbl.
+ */
+int
+st_delstring(Str_tbl *stp, const char *str)
+{
+ size_t len;
+ LenNode *lnp, ln = { 0 };
+ StrNode *snp, sn = { 0 };
+
+ /*
+ * String table can't have been cooked
+ */
+ assert((stp->st_flags & FLG_STTAB_COOKED) == 0);
+
+ len = strlen(str);
+ stp->st_fullstrsize -= len + 1;
+
+ if ((stp->st_flags & FLG_STTAB_COMPRESS) == 0)
+ return (0);
+
+ /*
+ * Determine which LenNode AVL node provides for this string length.
+ */
+ ln.ln_strlen = len;
+ if ((lnp = avl_find(stp->st_lentree, &ln, 0)) != NULL) {
+ sn.sn_str = str;
+ if ((snp = avl_find(lnp->ln_strtree, &sn, 0)) != NULL) {
+ /*
+ * Reduce the reference count, and if zero remove the
+ * node.
+ */
+ if (--snp->sn_refcnt == 0)
+ avl_remove(lnp->ln_strtree, snp);
+ return (0);
+ }
+ }
+
+ /*
+ * No strings of this length, or no string itself - someone goofed.
+ */
+ return (-1);
+}
+
+/*
+ * Tear down a String_Table structure.
+ */
+void
+st_destroy(Str_tbl *stp)
+{
+ Str_hash *sthash, *psthash;
+ Str_master *mstr, *pmstr;
+ uint_t i;
+
+ /*
+ * cleanup the master strings
+ */
+ for (mstr = stp->st_mstrlist, pmstr = 0; mstr;
+ mstr = mstr->sm_next) {
+ if (pmstr)
+ free(pmstr);
+ pmstr = mstr;
+ }
+ if (pmstr)
+ free(pmstr);
+
+ if (stp->st_hashbcks) {
+ for (i = 0; i < stp->st_hbckcnt; i++) {
+ for (sthash = stp->st_hashbcks[i], psthash = 0;
+ sthash; sthash = sthash->hi_next) {
+ if (psthash)
+ free(psthash);
+ psthash = sthash;
+ }
+ if (psthash)
+ free(psthash);
+ }
+ free(stp->st_hashbcks);
+ }
+ free(stp);
+}
+
+
+/*
+ * For a given string - copy it into the buffer associated with
+ * the string table - and return the offset it has been assigned.
+ *
+ * If a value of '-1' is returned - the string was not found in
+ * the Str_tbl.
+ */
+int
+st_setstring(Str_tbl *stp, const char *str, size_t *stoff)
+{
+ size_t stlen;
+ uint_t hashval;
+ Str_hash *sthash;
+ Str_master *mstr;
+ int i;
+
+ /*
+ * String table *must* have been previously cooked
+ */
+ assert(stp->st_strbuf);
+
+ assert(stp->st_flags & FLG_STTAB_COOKED);
+ stlen = strlen(str);
+ /*
+ * Null string always points to head of string table
+ */
+ if (stlen == 0) {
+ *stoff = 0;
+ return (0);
+ }
+
+ if ((stp->st_flags & FLG_STTAB_COMPRESS) == 0) {
+ size_t _stoff;
+
+ stlen++; /* count for trailing '\0' */
+ _stoff = stp->st_nextoff;
+ /*
+ * Have we overflowed our assigned buffer?
+ */
+ if ((_stoff + stlen) > stp->st_fullstrsize)
+ return (-1);
+ memcpy(stp->st_strbuf + _stoff, str, stlen);
+ *stoff = _stoff;
+ stp->st_nextoff += stlen;
+ return (0);
+ }
+
+ /*
+ * Calculate reverse hash for string.
+ */
+ hashval = HASHSEED;
+ for (i = stlen; i >= 0; i--) {
+ hashval = ((hashval << 5) + hashval) +
+ str[i]; /* h = ((h * 33) + c) */
+ }
+
+ for (sthash = stp->st_hashbcks[hashval % stp->st_hbckcnt]; sthash;
+ sthash = sthash->hi_next) {
+ const char *hstr;
+
+ if (sthash->hi_hashval != hashval)
+ continue;
+
+ hstr = &sthash->hi_mstr->sm_str[sthash->hi_mstr->sm_strlen -
+ sthash->hi_strlen];
+ if (strcmp(str, hstr) == 0)
+ break;
+ }
+
+ /*
+ * Did we find the string?
+ */
+ if (sthash == 0)
+ return (-1);
+
+ /*
+ * Has this string been copied into the string table?
+ */
+ mstr = sthash->hi_mstr;
+ if (mstr->sm_stroff == 0) {
+ size_t mstrlen = mstr->sm_strlen + 1;
+
+ mstr->sm_stroff = stp->st_nextoff;
+
+ /*
+ * Have we overflowed our assigned buffer?
+ */
+ if ((mstr->sm_stroff + mstrlen) > stp->st_fullstrsize)
+ return (-1);
+
+ (void) memcpy(stp->st_strbuf + mstr->sm_stroff,
+ mstr->sm_str, mstrlen);
+ stp->st_nextoff += mstrlen;
+ }
+
+ /*
+ * Calculate offset of (sub)string.
+ */
+ *stoff = mstr->sm_stroff + mstr->sm_strlen - sthash->hi_strlen;
+
+ return (0);
+}
+
+
+static int
+st_hash_insert(Str_tbl *stp, const char *str, size_t len)
+{
+ int i;
+ uint_t hashval = HASHSEED;
+ uint_t bckcnt = stp->st_hbckcnt;
+ Str_hash **hashbcks = stp->st_hashbcks;
+ Str_hash *sthash;
+ Str_master *mstr = 0;
+
+ /*
+ * We use a classic 'Bernstein k=33' hash function. But
+ * instead of hashing from the start of the string to the
+ * end, we do it in reverse.
+ *
+ * This way - we are essentially building all of the
+ * suffix hashvalues as we go. We can check to see if
+ * any suffixes already exist in the tree as we generate
+ * the hash.
+ */
+ for (i = len; i >= 0; i--) {
+ hashval = ((hashval << 5) + hashval) +
+ str[i]; /* h = ((h * 33) + c) */
+
+ for (sthash = hashbcks[hashval % bckcnt];
+ sthash; sthash = sthash->hi_next) {
+ const char *hstr;
+ Str_master *_mstr;
+
+ if (sthash->hi_hashval != hashval)
+ continue;
+
+ _mstr = sthash->hi_mstr;
+ hstr = &_mstr->sm_str[_mstr->sm_strlen -
+ sthash->hi_strlen];
+
+ if (strcmp(&str[i], hstr))
+ continue;
+
+ if (i == 0) {
+ /*
+ * Entry already in table, increment refcnt and
+ * get out.
+ */
+ sthash->hi_refcnt++;
+ return (0);
+ } else {
+ /*
+ * If this 'suffix' is presently a 'master
+ * string, then take over it's record.
+ */
+ if (sthash->hi_strlen == _mstr->sm_strlen) {
+ /*
+ * we should only do this once.
+ */
+ assert(mstr == 0);
+ mstr = _mstr;
+ }
+ }
+ }
+ }
+
+ /*
+ * Do we need a new master string, or can we take over
+ * one we already found in the table?
+ */
+ if (mstr == 0) {
+ /*
+ * allocate a new master string
+ */
+ if ((mstr = calloc(sizeof (Str_hash), 1)) == 0)
+ return (-1);
+ mstr->sm_next = stp->st_mstrlist;
+ stp->st_mstrlist = mstr;
+ stp->st_strsize += len + 1;
+ } else {
+ /*
+ * We are taking over a existing master string, the string size
+ * only increments by the difference between the current string
+ * and the previous master.
+ */
+ assert(len > mstr->sm_strlen);
+ stp->st_strsize += len - mstr->sm_strlen;
+ }
+
+ if ((sthash = calloc(sizeof (Str_hash), 1)) == 0)
+ return (-1);
+
+ mstr->sm_hashval = sthash->hi_hashval = hashval;
+ mstr->sm_strlen = sthash->hi_strlen = len;
+ mstr->sm_str = str;
+ sthash->hi_refcnt = 1;
+ sthash->hi_mstr = mstr;
+
+ /*
+ * Insert string element into head of hash list
+ */
+ hashval = hashval % bckcnt;
+ sthash->hi_next = hashbcks[hashval];
+ hashbcks[hashval] = sthash;
+ return (0);
+}
+
+/*
+ * Return amount of space required for the string table.
+ */
+size_t
+st_getstrtab_sz(Str_tbl *stp)
+{
+ assert(stp->st_fullstrsize > 0);
+
+ if ((stp->st_flags & FLG_STTAB_COMPRESS) == 0) {
+ stp->st_flags |= FLG_STTAB_COOKED;
+ return (stp->st_fullstrsize);
+ }
+
+ if ((stp->st_flags & FLG_STTAB_COOKED) == 0) {
+ LenNode *lnp;
+ void *cookie;
+
+ stp->st_flags |= FLG_STTAB_COOKED;
+ /*
+ * allocate a hash table about the size of # of
+ * strings input.
+ */
+ stp->st_hbckcnt = findprime(stp->st_strcnt);
+ if ((stp->st_hashbcks =
+ calloc(sizeof (Str_hash), stp->st_hbckcnt)) == NULL)
+ return (0);
+
+ /*
+ * We now walk all of the strings in the list, from shortest to
+ * longest, and insert them into the hashtable.
+ */
+ if ((lnp = avl_first(stp->st_lentree)) == NULL) {
+ /*
+ * Is it possible we have an empty string table, if so,
+ * the table still contains '\0', so return the size.
+ */
+ if (avl_numnodes(stp->st_lentree) == 0) {
+ assert(stp->st_strsize == 1);
+ return (stp->st_strsize);
+ }
+ return (0);
+ }
+
+ while (lnp) {
+ StrNode *snp;
+
+ /*
+ * Walk the string lists and insert them into the hash
+ * list. Once a string is inserted we no longer need
+ * it's entry, so the string can be freed.
+ */
+ for (snp = avl_first(lnp->ln_strtree); snp;
+ snp = AVL_NEXT(lnp->ln_strtree, snp)) {
+ if (st_hash_insert(stp, snp->sn_str,
+ lnp->ln_strlen) == -1)
+ return (0);
+ }
+
+ /*
+ * Now that the strings have been copied, walk the
+ * StrNode tree and free all the AVL nodes. Note,
+ * avl_destroy_nodes() beats avl_remove() as the
+ * latter balances the nodes as they are removed.
+ * We just want to tear the whole thing down fast.
+ */
+ cookie = NULL;
+ while ((snp = avl_destroy_nodes(lnp->ln_strtree,
+ &cookie)) != NULL)
+ free(snp);
+ avl_destroy(lnp->ln_strtree);
+ free(lnp->ln_strtree);
+ lnp->ln_strtree = NULL;
+
+ /*
+ * Move on to the next LenNode.
+ */
+ lnp = AVL_NEXT(stp->st_lentree, lnp);
+ }
+
+ /*
+ * Now that all of the strings have been freed, walk the
+ * LenNode tree and free all of the AVL nodes. Note,
+ * avl_destroy_nodes() beats avl_remove() as the latter
+ * balances the nodes as they are removed. We just want to
+ * tear the whole thing down fast.
+ */
+ cookie = NULL;
+ while ((lnp = avl_destroy_nodes(stp->st_lentree,
+ &cookie)) != NULL)
+ free(lnp);
+ avl_destroy(stp->st_lentree);
+ free(stp->st_lentree);
+ stp->st_lentree = 0;
+ }
+
+ assert(stp->st_strsize > 0);
+ assert(stp->st_fullstrsize >= stp->st_strsize);
+
+ return (stp->st_strsize);
+}
+
+/*
+ * Associate a buffer with a string table.
+ */
+const char *
+st_getstrbuf(Str_tbl *stp)
+{
+ return (stp->st_strbuf);
+}
+
+int
+st_setstrbuf(Str_tbl *stp, char *stbuf, size_t bufsize)
+{
+ assert(stp->st_flags & FLG_STTAB_COOKED);
+
+ if ((stp->st_flags & FLG_STTAB_COMPRESS) == 0) {
+ if (bufsize < stp->st_fullstrsize)
+ return (-1);
+ } else {
+ if (bufsize < stp->st_strsize)
+ return (-1);
+ }
+
+ stp->st_strbuf = stbuf;
+#ifdef DEBUG
+ /*
+ * for debug builds - start with a stringtable filled in
+ * with '0xff'. This makes it very easy to find wholes
+ * which we failed to fill in - in the strtab.
+ */
+ memset(stbuf, 0xff, bufsize);
+ stbuf[0] = '\0';
+#else
+ memset(stbuf, 0x0, bufsize);
+#endif
+ return (0);
+}
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