From 44a0e21795dcbd94d45ff143123f8b085754ea81 Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Wed, 7 Aug 2013 18:46:58 +0200 Subject: PcmBuffer: move code to new class ReusableBuffer ReusableBuffer is more generic. --- Makefile.am | 1 + src/pcm/PcmBuffer.cxx | 25 +------------ src/pcm/PcmBuffer.hxx | 23 ++++-------- src/pcm/PcmChannels.hxx | 2 +- src/pcm/PcmDsdUsb.hxx | 2 +- src/pcm/PcmFormat.hxx | 2 +- src/util/ReusableArray.hxx | 88 ++++++++++++++++++++++++++++++++++++++++++++++ 7 files changed, 99 insertions(+), 44 deletions(-) create mode 100644 src/util/ReusableArray.hxx diff --git a/Makefile.am b/Makefile.am index ffe1d8e42..00e9f6db5 100644 --- a/Makefile.am +++ b/Makefile.am @@ -261,6 +261,7 @@ endif # Generic utility library libutil_a_SOURCES = \ + src/util/ReusableArray.hxx \ src/util/AllocatedArray.hxx \ src/util/StringUtil.cxx src/util/StringUtil.hxx \ src/util/Tokenizer.cxx src/util/Tokenizer.hxx \ diff --git a/src/pcm/PcmBuffer.cxx b/src/pcm/PcmBuffer.cxx index adfd0e518..6ace399f3 100644 --- a/src/pcm/PcmBuffer.cxx +++ b/src/pcm/PcmBuffer.cxx @@ -21,16 +21,6 @@ #include "PcmBuffer.hxx" #include "poison.h" -/** - * Align the specified size to the next 8k boundary. - */ -constexpr -static size_t -align_8k(size_t size) -{ - return ((size - 1) | 0x1fff) + 1; -} - void * PcmBuffer::Get(size_t new_size) { @@ -39,18 +29,5 @@ PcmBuffer::Get(size_t new_size) be an error condition */ new_size = 1; - if (size < new_size) { - /* free the old buffer */ - g_free(buffer); - - size = align_8k(new_size); - buffer = g_malloc(size); - } else { - /* discard old buffer contents */ - poison_undefined(buffer, size); - } - - assert(size >= new_size); - - return buffer; + return buffer.Get(new_size); } diff --git a/src/pcm/PcmBuffer.hxx b/src/pcm/PcmBuffer.hxx index ae7030f76..2eddfb7f9 100644 --- a/src/pcm/PcmBuffer.hxx +++ b/src/pcm/PcmBuffer.hxx @@ -20,33 +20,22 @@ #ifndef PCM_BUFFER_HXX #define PCM_BUFFER_HXX -#include "check.h" +#include "util/ReusableArray.hxx" #include "gcc.h" -#include - -#include +#include /** * Manager for a temporary buffer which grows as needed. We could * allocate a new buffer every time pcm_convert() is called, but that * would put too much stress on the allocator. */ -struct PcmBuffer { - void *buffer; - - size_t size; - - PcmBuffer():buffer(nullptr), size(0) {} - - ~PcmBuffer() { - g_free(buffer); - } +class PcmBuffer { + ReusableArray buffer; +public: void Clear() { - g_free(buffer); - buffer = nullptr; - size = 0; + buffer.Clear(); } /** diff --git a/src/pcm/PcmChannels.hxx b/src/pcm/PcmChannels.hxx index 889a14a60..c67822825 100644 --- a/src/pcm/PcmChannels.hxx +++ b/src/pcm/PcmChannels.hxx @@ -23,7 +23,7 @@ #include #include -struct PcmBuffer; +class PcmBuffer; /** * Changes the number of channels in 16 bit PCM data. diff --git a/src/pcm/PcmDsdUsb.hxx b/src/pcm/PcmDsdUsb.hxx index 2cf8bfbba..3b7121465 100644 --- a/src/pcm/PcmDsdUsb.hxx +++ b/src/pcm/PcmDsdUsb.hxx @@ -25,7 +25,7 @@ #include #include -struct PcmBuffer; +class PcmBuffer; /** * Pack DSD 1 bit samples into (padded) 24 bit PCM samples for diff --git a/src/pcm/PcmFormat.hxx b/src/pcm/PcmFormat.hxx index b18b4f932..cc44d6dd5 100644 --- a/src/pcm/PcmFormat.hxx +++ b/src/pcm/PcmFormat.hxx @@ -25,7 +25,7 @@ #include #include -struct PcmBuffer; +class PcmBuffer; class PcmDither; /** diff --git a/src/util/ReusableArray.hxx b/src/util/ReusableArray.hxx new file mode 100644 index 000000000..30b1a9cd9 --- /dev/null +++ b/src/util/ReusableArray.hxx @@ -0,0 +1,88 @@ +/* + * Copyright (C) 2013 Max Kellermann + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * - Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef REUSABLE_ARRAY_HXX +#define REUSABLE_ARRAY_HXX + +#include + +#include "gcc.h" + +/** + * Manager for a temporary array which grows as needed. This attempts + * to reduce the number of consecutive heap allocations and + * deallocations. + * + * @param T the array element type + * @param M always allocate multiples of this number; must be a power of 2 + */ +template +class ReusableArray { + T *buffer; + size_t capacity; + +public: + ReusableArray():buffer(nullptr), capacity(0) {} + + ReusableArray(const ReusableArray &other) = delete; + ReusableArray &operator=(const ReusableArray &other) = delete; + + ~ReusableArray() { + delete[] buffer; + } + + /** + * Free resources allocated by this object. This invalidates + * the buffer returned by Get(). + */ + void Clear() { + delete[] buffer; + buffer = nullptr; + capacity = 0; + } + + /** + * Get the buffer, and guarantee a minimum size. This buffer + * becomes invalid with the next Get() call. + */ + gcc_malloc + T *Get(size_t size) { + if (gcc_unlikely(size > capacity)) { + /* too small: grow */ + delete[] buffer; + + capacity = ((size - 1) | (M - 1)) + 1; + buffer = new T[capacity]; + } + + return buffer; + } +}; + +#endif -- cgit v1.2.3