The Tor Browser / file diff

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/gfx/skia/trunk/src/ports/SkPurgeableMemoryBlock_android.cpp	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,110 @@
     1.4 +/*
     1.5 + * Copyright 2013 Google Inc.
     1.6 + *
     1.7 + * Use of this source code is governed by a BSD-style license that can be
     1.8 + * found in the LICENSE file.
     1.9 + */
    1.10 +
    1.11 +#include "SkPurgeableMemoryBlock.h"
    1.12 +
    1.13 +#include "android/ashmem.h"
    1.14 +#include <sys/mman.h>
    1.15 +#include <unistd.h>
    1.16 +
    1.17 +bool SkPurgeableMemoryBlock::IsSupported() {
    1.18 +    return true;
    1.19 +}
    1.20 +
    1.21 +#ifdef SK_DEBUG
    1.22 +bool SkPurgeableMemoryBlock::PlatformSupportsPurgingAllUnpinnedBlocks() {
    1.23 +    return false;
    1.24 +}
    1.25 +
    1.26 +bool SkPurgeableMemoryBlock::PurgeAllUnpinnedBlocks() {
    1.27 +    return false;
    1.28 +}
    1.29 +
    1.30 +bool SkPurgeableMemoryBlock::purge() {
    1.31 +    SkASSERT(!fPinned);
    1.32 +    if (-1 != fFD) {
    1.33 +        ashmem_purge_all_caches(fFD);
    1.34 +        return true;
    1.35 +    } else {
    1.36 +        return false;
    1.37 +    }
    1.38 +}
    1.39 +#endif
    1.40 +
    1.41 +// ashmem likes lengths on page boundaries.
    1.42 +static size_t round_to_page_size(size_t size) {
    1.43 +    const size_t mask = getpagesize() - 1;
    1.44 +    size_t newSize = (size + mask) & ~mask;
    1.45 +    return newSize;
    1.46 +}
    1.47 +
    1.48 +SkPurgeableMemoryBlock::SkPurgeableMemoryBlock(size_t size)
    1.49 +    : fAddr(NULL)
    1.50 +    , fSize(round_to_page_size(size))
    1.51 +    , fPinned(false)
    1.52 +    , fFD(-1) {
    1.53 +}
    1.54 +
    1.55 +SkPurgeableMemoryBlock::~SkPurgeableMemoryBlock() {
    1.56 +    if (-1 != fFD) {
    1.57 +        munmap(fAddr, fSize);
    1.58 +        close(fFD);
    1.59 +    }
    1.60 +}
    1.61 +
    1.62 +void* SkPurgeableMemoryBlock::pin(SkPurgeableMemoryBlock::PinResult* pinResult) {
    1.63 +    SkASSERT(!fPinned);
    1.64 +    if (-1 == fFD) {
    1.65 +        int fd = ashmem_create_region(NULL, fSize);
    1.66 +        if (-1 == fd) {
    1.67 +            SkDebugf("ashmem_create_region failed\n");
    1.68 +            return NULL;
    1.69 +        }
    1.70 +
    1.71 +        int err = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE);
    1.72 +        if (err != 0) {
    1.73 +            SkDebugf("ashmem_set_prot_region failed\n");
    1.74 +            close(fd);
    1.75 +            return NULL;
    1.76 +        }
    1.77 +
    1.78 +        void* addr = mmap(NULL, fSize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
    1.79 +        if (-1 == (long) addr) {
    1.80 +            SkDebugf("mmap failed\n");
    1.81 +            close(fd);
    1.82 +            return NULL;
    1.83 +        }
    1.84 +        fAddr = addr;
    1.85 +        fFD = fd;
    1.86 +        (void) ashmem_pin_region(fd, 0, 0);
    1.87 +        *pinResult = kUninitialized_PinResult;
    1.88 +        fPinned = true;
    1.89 +    } else {
    1.90 +        int pin = ashmem_pin_region(fFD, 0, 0);
    1.91 +        if (ASHMEM_NOT_PURGED == pin) {
    1.92 +            fPinned = true;
    1.93 +            *pinResult = kRetained_PinResult;
    1.94 +        } else if (ASHMEM_WAS_PURGED == pin) {
    1.95 +            fPinned = true;
    1.96 +            *pinResult = kUninitialized_PinResult;
    1.97 +        } else {
    1.98 +            // Failed.
    1.99 +            munmap(fAddr, fSize);
   1.100 +            close(fFD);
   1.101 +            fFD = -1;
   1.102 +            fAddr = NULL;
   1.103 +        }
   1.104 +    }
   1.105 +    return fAddr;
   1.106 +}
   1.107 +
   1.108 +void SkPurgeableMemoryBlock::unpin() {
   1.109 +    if (-1 != fFD) {
   1.110 +        ashmem_unpin_region(fFD, 0, 0);
   1.111 +        fPinned = false;
   1.112 +    }
   1.113 +}