From 3ef95f36437b4995d963387a04cbdfe34efb15eb Mon Sep 17 00:00:00 2001
From: Lubomir Rintel <lkundrak@v3.sk>
Date: Sat, 30 Jan 2016 23:07:11 +0100
Subject: [PATCH] SortableVector: avoid qsort()ing C++ objects

That's a sin to memcpy() a non-primitive type such as std::string. With
the current GCC libstdc++ implementation std::string inlines and copying
them directly causes no end of mayhem.

Valgrind just waved goodbye and exited through an open window.

Let's just get rid of the broken SortableVector class altogether, use
the standard std::sort interface, overload < instead of using a custom
comparator and implement swap to do the replaces correctly.
---
 src/Levels.cpp | 31 +++++++++++++++++++++++--------
 src/Levels.h   | 21 ++++-----------------
 2 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/src/Levels.cpp b/src/Levels.cpp
index 2579fcf..669a3c7 100644
--- a/src/Levels.cpp
+++ b/src/Levels.cpp
@@ -27,6 +27,7 @@
 
 #include <iostream>
 #include <string>
+#include <algorithm>
 
 
 static const char MISC_COLLECTION[] = "C99_My Levels";
@@ -99,16 +100,30 @@ compare_names(const std::string &a, const std::string &b)
     return ma[2].compare(mb[2]);
 }
 
-int
-LevelDesc::compare(const LevelDesc *a, const LevelDesc *b)
+bool
+operator<(LevelDesc a, LevelDesc b)
 {
-    return compare_names(a->file, b->file);
+    return compare_names(a.file, b.file) < 0;
 }
 
-int
-Collection::compare(const Collection *a, const Collection *b)
+void
+LevelDesc::swap(LevelDesc &a, LevelDesc &b)
+{
+    std::swap(a.file, b.file);
+}
+
+bool
+operator<(Collection a, Collection b)
+{
+    return compare_names(a.name, b.name) < 0;
+}
+
+void
+Collection::swap(Collection &a, Collection &b)
 {
-    return compare_names(a->name, b->name);
+    std::swap(a.file, b.file);
+    std::swap(a.name, b.name);
+    std::swap(a.levels, b.levels);
 }
 
 Levels::Levels(std::vector<std::string> dirs)
@@ -242,9 +257,9 @@ std::string Levels::levelName( int i, bool pretty )
 void
 Levels::sort()
 {
-    m_collections.sort();
+    std::sort(m_collections.begin(), m_collections.end());
     for (auto &collection: m_collections) {
-        collection.levels.sort();
+        std::sort(collection.levels.begin(), collection.levels.end());
     }
 }
 
diff --git a/src/Levels.h b/src/Levels.h
index aafe521..796fda2 100644
--- a/src/Levels.h
+++ b/src/Levels.h
@@ -20,19 +20,6 @@
 #include <cstdio>
 #include <sstream>
 #include <vector>
-#include <stdlib.h>
-
-template <typename T>
-class SortableVector : public std::vector<T> {
-public:
-    SortableVector() : std::vector<T>() {}
-
-    void sort()
-    {
-        qsort(std::vector<T>::data(), std::vector<T>::size(), sizeof(T),
-              (int (*)(const void *, const void *))T::compare);
-    }
-};
 
 struct LevelDesc {
     LevelDesc()
@@ -45,7 +32,7 @@ struct LevelDesc {
     {
     }
 
-    static int compare(const LevelDesc *a, const LevelDesc *b);
+    void swap(LevelDesc &a, LevelDesc &b);
 
     std::string file;
 };
@@ -65,11 +52,11 @@ struct Collection {
     {
     }
 
-    static int compare(const Collection *a, const Collection *b);
+    void swap(Collection &a, Collection &b);
 
     std::string file;
     std::string name;
-    SortableVector<LevelDesc> levels;
+    std::vector<LevelDesc> levels;
 };
 
 class Levels
@@ -107,7 +94,7 @@ class Levels
   bool scanCollection(const std::string& file);
 
   int m_numLevels;
-  SortableVector<Collection> m_collections;
+  std::vector<Collection> m_collections;
 };
 
 #endif //LEVELS_H