add refdict class, for holding a dictionary of reference-counted objects

-- experimental



git-svn-id: http://skia.googlecode.com/svn/trunk@730 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 80 insertions, 0 deletions

diff --git a/src/core/SkRefDict.cpp b/src/core/SkRefDict.cpp
new file mode 100644
index 0000000000..572ed7e180
--- /dev/null
+++ b/src/core/SkRefDict.cpp
@@ -0,0 +1,80 @@
+#include "SkRefDict.h"
+#include "SkString.h"
+
+struct SkRefDict::Impl {
+    Impl*       fNext;
+    SkString    fName;
+    SkRefCnt*   fData;
+};
+
+SkRefDict::SkRefDict() : fImpl(NULL) {}
+
+SkRefDict::~SkRefDict() {
+    this->removeAll();
+}
+
+SkRefCnt* SkRefDict::find(const char name[]) const {
+    if (NULL == name) {
+        return NULL;
+    }
+
+    Impl* rec = fImpl;
+    while (rec) {
+        if (rec->fName.equals(name)) {
+            return rec->fData;
+        }
+        rec = rec->fNext;
+    }
+    return NULL;
+}
+
+void SkRefDict::set(const char name[], SkRefCnt* data) {
+    if (NULL == name) {
+        return;
+    }
+
+    Impl* rec = fImpl;
+    Impl* prev = NULL;
+    while (rec) {
+        if (rec->fName.equals(name)) {
+            if (data) {
+                // replace
+                data->ref();
+                rec->fData->unref();
+                rec->fData = data;
+            } else {
+                // remove
+                rec->fData->unref();
+                if (prev) {
+                    prev->fNext = rec->fNext;
+                } else {
+                    fImpl = rec->fNext;
+                }
+            }
+            return;
+        }
+        prev = rec;
+        rec = rec->fNext;
+    }
+
+    // if get here, name was not found, so add it
+    data->ref();
+    rec = new Impl;
+    rec->fName.set(name);
+    rec->fData = data;
+    // prepend to the head of our list
+    rec->fNext = fImpl;
+    fImpl = rec;
+}
+
+void SkRefDict::removeAll() {
+    Impl* rec = fImpl;
+    while (rec) {
+        Impl* next = rec->fNext;
+        rec->fData->unref();
+        delete rec;
+        rec = next;
+    }
+    fImpl = NULL;
+}
+