From a538c52bc4f12a9719915856d838f71631d7cac3 Mon Sep 17 00:00:00 2001
From: Enno Rehling <enno.rehling@gmail.com>
Date: Thu, 24 Feb 2011 22:27:04 -0800
Subject: [PATCH] quicklists can be used as a set of pointers (this will be
 useful).

---
 src/util/quicklist.c      | 35 ++++++++++++++++++++++++++++++++---
 src/util/quicklist.h      |  5 ++++-
 src/util/quicklist_test.c | 29 +++++++++++++++++++++++++++++
 3 files changed, 65 insertions(+), 4 deletions(-)

diff --git a/src/util/quicklist.c b/src/util/quicklist.c
index db06108c0..f5b0bc8bd 100644
--- a/src/util/quicklist.c
+++ b/src/util/quicklist.c
@@ -29,7 +29,7 @@ struct quicklist {
 };
 
 
-void * ql_get(quicklist * ql, int index) {
+void * ql_get(const quicklist * ql, int index) {
   return (ql && index<ql->num_elements)?ql->elements[index]:ql_get(ql->next, index-ql->num_elements);
 }
 
@@ -43,7 +43,7 @@ void ql_push(quicklist ** qlp, void * data) {
     qlp = &(*qlp)->next;
   }
   if (!*qlp) {
-    ql = malloc(sizeof(quicklist));
+    ql = (quicklist *)malloc(sizeof(quicklist));
     ql->num_elements = 0;
     ql->next = 0;
     *qlp = ql;
@@ -94,7 +94,7 @@ int ql_insert(quicklist ** qlp, int index, void * data) {
       ql->elements[index]=data;
       ++ql->num_elements;
     } else {
-      quicklist * qn = malloc(sizeof(quicklist));
+      quicklist * qn = (quicklist *)malloc(sizeof(quicklist));
       qn->next = ql->next;
       ql->next = qn;
       qn->num_elements = QL_LIMIT;
@@ -145,3 +145,32 @@ void ql_free(struct quicklist * ql)
   if (ql->next) ql_free(ql->next);
   free(ql);
 }
+
+int ql_set_insert(struct quicklist ** qlp, void * data)
+{
+  if (*qlp) {
+    quicklist * ql = *qlp;
+    if (ql->num_elements>0 && ql->elements[ql->num_elements-1] < data) {
+      if (ql->num_elements==QL_MAXSIZE || (ql->next && ql->next->elements[0]<=data)) {
+        return ql_set_insert(&ql->next, data);
+      } else {
+        ql->elements[ql->num_elements++] = data;
+      }
+      return 0;
+    } else {
+      int i;
+      /* TODO: OPT | binary search */
+      for (i=0;i!=ql->num_elements;++i) {
+        if (data < ql->elements[i]) {
+          ql_insert(qlp, i, data);
+          return 0;
+        }
+        if (data == ql->elements[i]) {
+          return 1;
+        }
+      }
+    }
+  }
+  ql_push(qlp, data);
+  return 0;
+}
\ No newline at end of file
diff --git a/src/util/quicklist.h b/src/util/quicklist.h
index 89fc95cf7..cc7186a31 100644
--- a/src/util/quicklist.h
+++ b/src/util/quicklist.h
@@ -23,7 +23,7 @@ extern "C" {
 
 /* see http://en.wikipedia.org/wiki/Unrolled_linked_list */
 typedef struct quicklist quicklist;
-void * ql_get(struct quicklist * ql, int index);
+void * ql_get(const struct quicklist * ql, int index);
 int ql_length(const struct quicklist * ql);
 void ql_push(struct quicklist ** qlp, void * data);
 int ql_delete(struct quicklist ** qlp, int index);
@@ -31,6 +31,9 @@ int ql_insert(struct quicklist ** qlp, int index, void * data);
 void ql_foreach(struct quicklist * ql, void (*cb)(void *));
 int ql_advance(struct quicklist ** iterator, int * index, int stride);
 void ql_free(struct quicklist * ql);
+
+/* you can use it as a set (sorted pointers)*/
+int ql_set_insert(struct quicklist ** qlp, void * data);
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/util/quicklist_test.c b/src/util/quicklist_test.c
index 5125a9b37..bb82afa12 100644
--- a/src/util/quicklist_test.c
+++ b/src/util/quicklist_test.c
@@ -17,6 +17,33 @@ static void test_insert(CuTest * tc) {
   }
 }
 
+static void test_insert_delete_gives_null(CuTest * tc) {
+  struct quicklist * ql = NULL;
+  ql_push(&ql, (void*)42);
+  ql_delete(&ql, 0);
+  CuAssertPtrEquals(tc, 0, ql);
+}
+
+static void test_set_insert(CuTest * tc) {
+  struct quicklist * ql = NULL;
+  int a;
+  a = ql_set_insert(&ql, (void*)42);
+  CuAssertIntEquals(tc, 1, ql_length(ql));
+  CuAssertIntEquals(tc, 0, a);
+  a = ql_set_insert(&ql, (void*)43);
+  CuAssertIntEquals(tc, 2, ql_length(ql));
+  CuAssertIntEquals(tc, 0, a);
+  a = ql_set_insert(&ql, (void*)42);
+  CuAssertIntEquals(tc, 2, ql_length(ql));
+  CuAssertIntEquals(tc, 1, a);
+  a = ql_set_insert(&ql, (void*)41);
+  CuAssertIntEquals(tc, 0, a);
+  CuAssertIntEquals(tc, 3, ql_length(ql));
+  CuAssertIntEquals(tc, 41, (int)ql_get(ql, 0));
+  CuAssertIntEquals(tc, 42, (int)ql_get(ql, 1));
+  CuAssertIntEquals(tc, 43, (int)ql_get(ql, 2));
+}
+
 static void test_advance(CuTest * tc) {
   struct quicklist * ql = NULL, *qli;
   int i, n = 31;
@@ -84,8 +111,10 @@ CuSuite* get_quicklist_suite(void)
   SUITE_ADD_TEST(suite, test_advance);
   SUITE_ADD_TEST(suite, test_push);
   SUITE_ADD_TEST(suite, test_insert);
+  SUITE_ADD_TEST(suite, test_insert_delete_gives_null);
   SUITE_ADD_TEST(suite, test_insert_many);
   SUITE_ADD_TEST(suite, test_delete_rand);
   SUITE_ADD_TEST(suite, test_delete_edgecases);
+  SUITE_ADD_TEST(suite, test_set_insert);
   return suite;
 }