ICU-62108.0.1.tar.gz

[apple/icu.git] / icuSources / common / cmemory.h

diff --git a/icuSources/common/cmemory.h b/icuSources/common/cmemory.h
index 665a82276927a481324e5e568397af52c8ffcc4e..e3532c759e1e982425ae2bfdc7d2f9de1e8724d2 100644 (file)
--- a/icuSources/common/cmemory.h
+++ b/icuSources/common/cmemory.h
@@ -36,31 +36,10 @@
 #include <stdio.h>
 #endif
 
-#if U_DEBUG
-
-/*
- * The C++ standard requires that the source pointer for memcpy() & memmove()
- * is valid, not NULL, and not at the end of an allocated memory block.
- * In debug mode, we read one byte from the source point to verify that it's
- * a valid, readable pointer.
- */
-
-U_CAPI void uprv_checkValidMemory(const void *p, size_t n);
-
-#define uprv_memcpy(dst, src, size) ( \
-    uprv_checkValidMemory(src, 1), \
-    U_STANDARD_CPP_NAMESPACE memcpy(dst, src, size))
-#define uprv_memmove(dst, src, size) ( \
-    uprv_checkValidMemory(src, 1), \
-    U_STANDARD_CPP_NAMESPACE memmove(dst, src, size))
-
-#else
 
 #define uprv_memcpy(dst, src, size) U_STANDARD_CPP_NAMESPACE memcpy(dst, src, size)
 #define uprv_memmove(dst, src, size) U_STANDARD_CPP_NAMESPACE memmove(dst, src, size)
 
-#endif  /* U_DEBUG */
-
 /**
  * \def UPRV_LENGTHOF
  * Convenience macro to determine the length of a fixed array at compile-time.
@@ -162,7 +141,6 @@ public:
      * @param p simple pointer to an array of T items that is adopted
      */
     explicit LocalMemory(T *p=NULL) : LocalPointerBase<T>(p) {}
-#if U_HAVE_RVALUE_REFERENCES
     /**
      * Move constructor, leaves src with isNull().
      * @param src source smart pointer
@@ -170,14 +148,12 @@ public:
     LocalMemory(LocalMemory<T> &&src) U_NOEXCEPT : LocalPointerBase<T>(src.ptr) {
         src.ptr=NULL;
     }
-#endif
     /**
      * Destructor deletes the memory it owns.
      */
     ~LocalMemory() {
         uprv_free(LocalPointerBase<T>::ptr);
     }
-#if U_HAVE_RVALUE_REFERENCES
     /**
      * Move assignment operator, leaves src with isNull().
      * The behavior is undefined if *this and src are the same object.
@@ -187,7 +163,6 @@ public:
     LocalMemory<T> &operator=(LocalMemory<T> &&src) U_NOEXCEPT {
         return moveFrom(src);
     }
-#endif
     /**
      * Move assignment, leaves src with isNull().
      * The behavior is undefined if *this and src are the same object.
@@ -312,10 +287,26 @@ public:
      * Default constructor initializes with internal T[stackCapacity] buffer.
      */
     MaybeStackArray() : ptr(stackArray), capacity(stackCapacity), needToRelease(FALSE) {}
+    /**
+     * Automatically allocates the heap array if the argument is larger than the stack capacity.
+     * Intended for use when an approximate capacity is known at compile time but the true
+     * capacity is not known until runtime.
+     */
+    MaybeStackArray(int32_t newCapacity) : MaybeStackArray() {
+        if (capacity < newCapacity) { resize(newCapacity); }
+    };
     /**
      * Destructor deletes the array (if owned).
      */
     ~MaybeStackArray() { releaseArray(); }
+    /**
+     * Move constructor: transfers ownership or copies the stack array.
+     */
+    MaybeStackArray(MaybeStackArray<T, stackCapacity> &&src) U_NOEXCEPT;
+    /**
+     * Move assignment: transfers ownership or copies the stack array.
+     */
+    MaybeStackArray<T, stackCapacity> &operator=(MaybeStackArray<T, stackCapacity> &&src) U_NOEXCEPT;
     /**
      * Returns the array capacity (number of T items).
      * @return array capacity
@@ -393,6 +384,11 @@ private:
             uprv_free(ptr);
         }
     }
+    void resetToStackArray() {
+        ptr=stackArray;
+        capacity=stackCapacity;
+        needToRelease=FALSE;
+    }
     /* No comparison operators with other MaybeStackArray's. */
     bool operator==(const MaybeStackArray & /*other*/) {return FALSE;}
     bool operator!=(const MaybeStackArray & /*other*/) {return TRUE;}
@@ -415,6 +411,34 @@ private:
 #endif
 };
 
+template<typename T, int32_t stackCapacity>
+icu::MaybeStackArray<T, stackCapacity>::MaybeStackArray(
+        MaybeStackArray <T, stackCapacity>&& src) U_NOEXCEPT
+        : ptr(src.ptr), capacity(src.capacity), needToRelease(src.needToRelease) {
+    if (src.ptr == src.stackArray) {
+        ptr = stackArray;
+        uprv_memcpy(stackArray, src.stackArray, sizeof(T) * src.capacity);
+    } else {
+        src.resetToStackArray();  // take ownership away from src
+    }
+}
+
+template<typename T, int32_t stackCapacity>
+inline MaybeStackArray <T, stackCapacity>&
+MaybeStackArray<T, stackCapacity>::operator=(MaybeStackArray <T, stackCapacity>&& src) U_NOEXCEPT {
+    releaseArray();  // in case this instance had its own memory allocated
+    capacity = src.capacity;
+    needToRelease = src.needToRelease;
+    if (src.ptr == src.stackArray) {
+        ptr = stackArray;
+        uprv_memcpy(stackArray, src.stackArray, sizeof(T) * src.capacity);
+    } else {
+        ptr = src.ptr;
+        src.resetToStackArray();  // take ownership away from src
+    }
+    return *this;
+}
+
 template<typename T, int32_t stackCapacity>
 inline T *MaybeStackArray<T, stackCapacity>::resize(int32_t newCapacity, int32_t length) {
     if(newCapacity>0) {
@@ -464,9 +488,7 @@ inline T *MaybeStackArray<T, stackCapacity>::orphanOrClone(int32_t length, int32
         uprv_memcpy(p, ptr, (size_t)length*sizeof(T));
     }
     resultCapacity=length;
-    ptr=stackArray;
-    capacity=stackCapacity;
-    needToRelease=FALSE;
+    resetToStackArray();
     return p;
 }