bslma_testallocatorexception.h

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/// @file bslma_testallocatorexception.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bslma_testallocatorexception.h                                     -*-C++-*-
#ifndef INCLUDED_BSLMA_TESTALLOCATOREXCEPTION
#define INCLUDED_BSLMA_TESTALLOCATOREXCEPTION
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bslma_testallocatorexception bslma_testallocatorexception
/// @brief  Provide an exception class for memory allocation operations.
/// @addtogroup bsl
/// @{
/// @addtogroup bslma
/// @{
/// @addtogroup bslma_testallocatorexception
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bslma_testallocatorexception-purpose"> Purpose</a>
/// * <a href="#bslma_testallocatorexception-classes"> Classes </a>
/// * <a href="#bslma_testallocatorexception-description"> Description </a>
///   * <a href="#bslma_testallocatorexception-usage"> Usage </a>
///
/// # Purpose {#bslma_testallocatorexception-purpose}
/// Provide an exception class for memory allocation operations.
///
/// # Classes {#bslma_testallocatorexception-classes}
///
/// -  bslma::TestAllocatorException: exception containing allocation information
///
/// # Description {#bslma_testallocatorexception-description}
/// This component defines a simple exception object for testing
/// exceptions during memory allocation operations.  The exception object
/// `bslma::TestAllocatorException` contains information about the allocation
/// request, which can be queried for by the "catcher" of this exception.
///
/// ## Usage {#bslma_testallocatorexception-usage}
///
///
/// In the following example, the `bslma::TestAllocatorException` object is
/// thrown by the `allocate` method of the `my_Allocator` object after the
/// number of allocation requests exceeds the allocator's allocation limit.
/// This example demonstrates how to use a user-defined allocator (e.g.,
/// `my_Allocator`) and `bslma::TestAllocatorException` to verify that an object
/// (e.g., `my_ShortArray`) under test is exception-neutral:
/// @code
/// // my_allocator.h
/// #include <bslma_allocator.h>
///
/// class my_Allocator : public bslma::Allocator {
///     int d_allocationLimit;
///     // ...
///
///   private:
///     // NOT IMPLEMENTED
///     my_Allocator(const my_Allocator&);
///     my_Allocator& operator=(const my_Allocator&);
///
///   public:
///     // CREATORS
///     my_Allocator() : d_allocationLimit(-1) {}
///     ~my_Allocator() {}
///
///     void *allocate(int size);
///     void deallocate(void *address) { free(address); }
///     void setAllocationLimit(int limit){ d_allocationLimit = limit; }
///     int allocationLimit() const { return d_allocationLimit; }
///     // ...
/// };
///
/// // my_allocator.cpp
/// #include <my_allocator.h>
///
/// void *my_Allocator::allocate(int size)
/// {
/// #ifdef BDE_BUILD_TARGET_EXC
///     if (0 <= d_allocationLimit) {
///         --d_allocationLimit;
///         if (0 > d_allocationLimit) {
///             throw bslma::TestAllocatorException(size);
///         }
///     }
/// #endif
///     return (void *)malloc(size);
/// }
/// @endcode
/// Note that the macro `BDE_BUILD_TARGET_EXC` is defined at compile-time to
/// indicate whether exceptions are enabled.  In the above code, if exceptions
/// are not enabled, the code that throws `bslma::TestAllocatorException` is
/// never executed.  The following is the test driver for `my_ShortArray`.
///
/// Note that "\$" must be replaced by "\" in the preprocessor macro definitions
/// that follow.  The "$" symbols are present in this header file to avoid a
/// diagnostic elicited by some compilers (e.g., "warning: multi-line comment").
/// @code
/// // my_shortarray.t.cpp
/// #include <my_shortarray.h>
/// #include <my_testallocator.h>
/// #include <bslma_testallocatorexception.h>
///
/// // ...
///
/// #ifdef BDE_BUILD_TARGET_EXC
/// #define BSLMA_TESTALLOCATOR_EXCEPTION_TEST_BEGIN {                       \$
/// {                                                                        \$
///     static int firstTime = 1;                                            \$
///     if (veryVerbose && firstTime) std::cout <<                           \$
///         "### BSLMA EXCEPTION TEST -- (ENABLED) --" << std::endl;         \$
///     firstTime = 0;                                                       \$
/// }                                                                        \$
/// if (veryVeryVerbose) std::cout <<                                        \$
///     "### Begin bslma exception test." << std::endl;                      \$
/// int bslmaExceptionCounter = 0;                                           \$
/// static int bslmaExceptionLimit = 100;                                    \$
/// testAllocator.setAllocationLimit(bslmaExceptionCounter);                 \$
/// do {                                                                     \$
///     try {
///
/// #define BSLMA_TESTALLOCATOR_EXCEPTION_TEST_END                           \$
///     } catch (bslma::TestAllocatorException& e) {                         \$
///         if (veryVerbose && bslmaExceptionLimit || veryVeryVerbose) {     \$
///             --bslmaExceptionLimit;                                       \$
///             std::cout << "(*** " << bslmaExceptionCounter << ')';        \$
///             if (veryVeryVerbose) { std::cout << " BSLMA_EXCEPTION: "     \$
///                 << "alloc limit = " << bslmaExceptionCounter << ", "     \$
///                 << "last alloc size = " << e.numBytes();                 \$
///             }                                                            \$
///             else if (0 == bslmaExceptionLimit) {                         \$
///                 std::cout << " [ Note: 'bslmaExceptionLimit' reached. ]";\$
///             }                                                            \$
///             std::cout << std::endl;                                      \$
///         }                                                                \$
///         testAllocator.setAllocationLimit(++bslmaExceptionCounter);       \$
///         continue;                                                        \$
///     }                                                                    \$
///     testAllocator.setAllocationLimit(-1);                                \$
///     break;                                                               \$
/// } while (1);                                                             \$
/// if (veryVeryVerbose) std::cout <<                                        \$
///     "### End bslma exception test." << std::endl;                        \$
/// }
/// #else
/// #define BSLMA_TESTALLOCATOR_EXCEPTION_TEST_BEGIN                         \$
/// {                                                                        \$
///     static int firstTime = 1;                                            \$
///     if (verbose && firstTime) { std::cout <<                             \$
///         "### BSLMA EXCEPTION TEST -- (NOT ENABLED) --" << std::endl;     \$
///         firstTime = 0;                                                   \$
///     }                                                                    \$
/// }
/// #define BSLMA_TESTALLOCATOR_EXCEPTION_TEST_END
/// #endif
///
/// // ...
///
/// /// Return `true` if the specified initial `numElement` in the specified
/// /// `array1` and `array2` have the same values, and `false` otherwise.
/// static
/// bool areEqual(const short *array1, const short *array2, int numElement)
/// {
///     for (int i = 0; i < numElement; ++i) {
///         if (array1[i] != array2[i]) return false;
///     }
///     return true;
/// }
///
/// int main(int argc, char *argv[]) {
///     int test = argc > 1 ? atoi(argv[1]) : 0;
///     int verbose = argc > 2;
///     int veryVerbose = argc > 3;
///     int veryVeryVerbose = argc > 4;
///
///     my_Allocator testAllocator;
///
///     switch (test) { case 0:
///
///       // ...
///
///       case 6: {
///         struct {
///             int d_line;
///             int d_numElem;
///             short d_exp[NUM_VALUES];
///         } DATA[] = {
///             { L_, 0, {} },
///             { L_, 1, { V0 } },
///             { L_, 5, { V0, V1, V2, V3, V4 } }
///         };
///
///         const int NUM_TEST = sizeof DATA / sizeof *DATA;
///
///         for (int ti = 0; ti < NUM_TEST; ++ti) {
///             const int    LINE     = DATA[ti].d_line;
///             const int    NUM_ELEM = DATA[ti].d_numElem;
///             const short *EXP      = DATA[ti].d_exp;
///
///             BSLMA_TESTALLOCATOR_EXCEPTION_TEST_BEGIN {
///                 my_ShortArray mA(&testAllocator);
///                 const my_ShortArray& A = mA;
///                 for (int ei = 0; ei < NUM_ELEM; ++ei) {
///                     mA.append(VALUES[ei]);
///                 }
///                 if (veryVerbose) { P_(ti); P_(NUM_ELEM); P(A); }
///                 LOOP2_ASSERT(LINE, ti, areEqual(EXP, A, NUM_ELEM));
///             } BSLMA_TESTALLOCATOR_EXCEPTION_TEST_END
///         }
///
///         if (veryVerbose) std::cout << testAllocator << std::endl;
///       } break;
///
///       // ...
///
///     }
///
///     // ...
/// }
/// @endcode
/// @}
/** @} */
/** @} */
 
/** @addtogroup bsl
 * @{
 */
/** @addtogroup bslma
 * @{
 */
/** @addtogroup bslma_testallocatorexception
 * @{
 */
 
#include <bslscm_version.h>
 
#include <bslma_allocator.h>
 
#include <bsls_exceptionutil.h>
#include <bsls_keyword.h>
 
#include <new>          // For 'std::bad_alloc'
 
 
 
namespace bslma {
 
                        // ============================
                        // class TestAllocatorException
                        // ============================
 
/// This class defines an exception object for memory allocation operations.
/// Objects of this class contain information about an allocation request.
///
/// See @ref bslma_testallocatorexception 
class TestAllocatorException : public std::bad_alloc {
 
  public:
    // PUBLIC TYPES
 
    /// Alias for the type used by the `Allocator` protocol to request a
    /// memory allocation of a given size.
    typedef Allocator::size_type size_type;
 
  private:
    // DATA
    size_type d_numBytes;  // number of bytes requested in an allocation
                           // operation
 
  public:
    // CREATORS
 
    /// Create an exception object initialized with the specified `numBytes`
    /// that indicates an allocation request size.
    explicit TestAllocatorException(size_type numBytes);
 
    /// Destroy this object.
     ~TestAllocatorException();
 
    // ACCESSORS
 
    /// Return the number of bytes (supplied at construction) that indicates
    /// an allocation request size.
    size_type numBytes() const;
 
    /// Return a pointer to the string literal "bslma::TestAllocatorException"
    /// having a storage duration of the lifetime of the program.  
    /// 
    /// \note Note that   the caller should *not* attempt to free this memory.
    const char *what() const BSLS_EXCEPTION_VIRTUAL_NOTHROW
                                                         BSLS_KEYWORD_OVERRIDE;
};
 
// ============================================================================
//                      INLINE FUNCTION DEFINITIONS
// ============================================================================
 
                        // ----------------------------
                        // class TestAllocatorException
                        // ----------------------------
 
// CREATORS
inline
TestAllocatorException::TestAllocatorException(size_type numBytes)
: d_numBytes(numBytes)
{
}
 
// ACCESSORS
inline
TestAllocatorException::size_type
TestAllocatorException::numBytes() const
{
    return d_numBytes;
}
 
inline
const char *
TestAllocatorException::what() const BSLS_EXCEPTION_VIRTUAL_NOTHROW
{
    return "bslma::TestAllocatorException";
}
 
}  // close package namespace
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2013 Bloomberg Finance L.P.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------- END-OF-FILE ----------------------------------
 
/** @} */
/** @} */
/** @} */