1 files changed, 156 insertions, 0 deletions

diff --git a/lib/libpmcstat/libpmcstat_string.c b/lib/libpmcstat/libpmcstat_string.c
new file mode 100644
index 000000000000..d7932c680eb4
--- /dev/null
+++ b/lib/libpmcstat/libpmcstat_string.c
@@ -0,0 +1,156 @@
+/*-
+ * Copyright (c) 2003-2008 Joseph Koshy
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/cpuset.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/pmc.h>
+
+#include <assert.h>
+#include <err.h>
+#include <errno.h>
+#include <pmc.h>
+#include <pmclog.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+
+#include "libpmcstat.h"
+
+static LIST_HEAD(,pmcstat_string)	pmcstat_string_hash[PMCSTAT_NHASH];
+
+/*
+ * Intern a copy of string 's', and return a pointer to the
+ * interned structure.
+ */
+
+pmcstat_interned_string
+pmcstat_string_intern(const char *s)
+{
+	struct pmcstat_string *ps;
+	const struct pmcstat_string *cps;
+	int hash, len;
+
+	if ((cps = pmcstat_string_lookup(s)) != NULL)
+		return (cps);
+
+	hash = pmcstat_string_compute_hash(s);
+	len  = strlen(s);
+
+	if ((ps = malloc(sizeof(*ps))) == NULL)
+		err(EX_OSERR, "ERROR: Could not intern string");
+	ps->ps_len = len;
+	ps->ps_hash = hash;
+	ps->ps_string = strdup(s);
+	LIST_INSERT_HEAD(&pmcstat_string_hash[hash], ps, ps_next);
+	return ((pmcstat_interned_string) ps);
+}
+
+const char *
+pmcstat_string_unintern(pmcstat_interned_string str)
+{
+	const char *s;
+
+	s = ((const struct pmcstat_string *) str)->ps_string;
+	return (s);
+}
+
+/*
+ * Compute a 'hash' value for a string.
+ */
+
+int
+pmcstat_string_compute_hash(const char *s)
+{
+	unsigned hash;
+
+	for (hash = 2166136261; *s; s++)
+		hash = (hash ^ *s) * 16777619;
+
+	return (hash & PMCSTAT_HASH_MASK);
+}
+
+pmcstat_interned_string
+pmcstat_string_lookup(const char *s)
+{
+	struct pmcstat_string *ps;
+	int hash, len;
+
+	hash = pmcstat_string_compute_hash(s);
+	len = strlen(s);
+
+	LIST_FOREACH(ps, &pmcstat_string_hash[hash], ps_next)
+	    if (ps->ps_len == len && ps->ps_hash == hash &&
+		strcmp(ps->ps_string, s) == 0)
+		    return (ps);
+	return (NULL);
+}
+
+int
+pmcstat_string_lookup_hash(pmcstat_interned_string s)
+{
+	const struct pmcstat_string *ps;
+
+	ps = (const struct pmcstat_string *) s;
+	return (ps->ps_hash);
+}
+
+/*
+ * Destroy the string table, free'ing up space.
+ */
+
+void
+pmcstat_string_shutdown(void)
+{
+	int i;
+	struct pmcstat_string *ps, *pstmp;
+
+	for (i = 0; i < PMCSTAT_NHASH; i++)
+		LIST_FOREACH_SAFE(ps, &pmcstat_string_hash[i], ps_next,
+		    pstmp) {
+			LIST_REMOVE(ps, ps_next);
+			free(ps->ps_string);
+			free(ps);
+		}
+}
+
+/*
+ * Initialize the string interning facility.
+ */
+
+void
+pmcstat_string_initialize(void)
+{
+	int i;
+
+	for (i = 0; i < PMCSTAT_NHASH; i++)
+		LIST_INIT(&pmcstat_string_hash[i]);
+}