omhdfs: files now kept inside a hashtable for use by multiple actions

Note:compiles, but not yet tested

2 files changed, 30 insertions, 1 deletions

diff --git a/runtime/hashtable.h b/runtime/hashtable.h
index b90781ab..0f980127 100644
--- a/runtime/hashtable.h
+++ b/runtime/hashtable.h
@@ -196,4 +196,6 @@ hashtable_destroy(struct hashtable *h, int free_values);
  * 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.
-*/
+ */
+unsigned int hash_from_string(void *k) ;
+int key_equals_string(void *key1, void *key2);
diff --git a/runtime/hashtable/hashtable.c b/runtime/hashtable/hashtable.c
index a10e3bc6..e2a2b3f4 100644
--- a/runtime/hashtable/hashtable.c
+++ b/runtime/hashtable/hashtable.c
@@ -241,6 +241,33 @@ hashtable_destroy(struct hashtable *h, int free_values)
     free(h);
 }
 
+/* some generic hash functions */
+
+/* one provided by Aaaron Wiebe based on perl's hashng algorithm 
+ * (so probably pretty generic). Not for excessively large strings!
+ */
+unsigned int
+hash_from_string(void *k) 
+{
+    int len;
+    char *rkey = (char*) k;
+    unsigned hashval = 1;
+
+    len = (int) strlen(rkey);
+    while (len--)
+        hashval = hashval * 33 + *rkey++;
+
+    return hashval;
+}
+
+
+int
+key_equals_string(void *key1, void *key2)
+{
+	return strcmp(key1, key2);
+}
+
+
 /*
  * Copyright (c) 2002, Christopher Clark
  * All rights reserved.