1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/string/src/nsSubstring.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,342 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim:set ts=2 sw=2 sts=2 et cindent: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifdef DEBUG
1.11 +#define ENABLE_STRING_STATS
1.12 +#endif
1.13 +
1.14 +#include "mozilla/Atomics.h"
1.15 +#include "mozilla/MemoryReporting.h"
1.16 +
1.17 +#ifdef ENABLE_STRING_STATS
1.18 +#include <stdio.h>
1.19 +#endif
1.20 +
1.21 +#include <stdlib.h>
1.22 +#include "nsSubstring.h"
1.23 +#include "nsString.h"
1.24 +#include "nsStringBuffer.h"
1.25 +#include "nsDependentString.h"
1.26 +#include "nsMemory.h"
1.27 +#include "prprf.h"
1.28 +#include "nsStaticAtom.h"
1.29 +#include "nsCOMPtr.h"
1.30 +
1.31 +#include "mozilla/IntegerPrintfMacros.h"
1.32 +#ifdef XP_WIN
1.33 +#include <windows.h>
1.34 +#include <process.h>
1.35 +#define getpid() _getpid()
1.36 +#define pthread_self() GetCurrentThreadId()
1.37 +#else
1.38 +#include <pthread.h>
1.39 +#include <unistd.h>
1.40 +#endif
1.41 +
1.42 +using mozilla::Atomic;
1.43 +
1.44 +// ---------------------------------------------------------------------------
1.45 +
1.46 +static const char16_t gNullChar = 0;
1.47 +
1.48 +char* const nsCharTraits<char>::sEmptyBuffer =
1.49 + (char*) const_cast<char16_t*>(&gNullChar);
1.50 +char16_t* const nsCharTraits<char16_t>::sEmptyBuffer =
1.51 + const_cast<char16_t*>(&gNullChar);
1.52 +
1.53 +// ---------------------------------------------------------------------------
1.54 +
1.55 +#ifdef ENABLE_STRING_STATS
1.56 +class nsStringStats
1.57 + {
1.58 + public:
1.59 + nsStringStats()
1.60 + : mAllocCount(0), mReallocCount(0), mFreeCount(0), mShareCount(0) {}
1.61 +
1.62 + ~nsStringStats()
1.63 + {
1.64 + // this is a hack to suppress duplicate string stats printing
1.65 + // in seamonkey as a result of the string code being linked
1.66 + // into seamonkey and libxpcom! :-(
1.67 + if (!mAllocCount && !mAdoptCount)
1.68 + return;
1.69 +
1.70 + printf("nsStringStats\n");
1.71 + printf(" => mAllocCount: % 10d\n", int(mAllocCount));
1.72 + printf(" => mReallocCount: % 10d\n", int(mReallocCount));
1.73 + printf(" => mFreeCount: % 10d", int(mFreeCount));
1.74 + if (mAllocCount > mFreeCount)
1.75 + printf(" -- LEAKED %d !!!\n", mAllocCount - mFreeCount);
1.76 + else
1.77 + printf("\n");
1.78 + printf(" => mShareCount: % 10d\n", int(mShareCount));
1.79 + printf(" => mAdoptCount: % 10d\n", int(mAdoptCount));
1.80 + printf(" => mAdoptFreeCount: % 10d", int(mAdoptFreeCount));
1.81 + if (mAdoptCount > mAdoptFreeCount)
1.82 + printf(" -- LEAKED %d !!!\n", mAdoptCount - mAdoptFreeCount);
1.83 + else
1.84 + printf("\n");
1.85 + printf(" => Process ID: %" PRIuPTR ", Thread ID: %" PRIuPTR "\n",
1.86 + uintptr_t(getpid()), uintptr_t(pthread_self()));
1.87 + }
1.88 +
1.89 + Atomic<int32_t> mAllocCount;
1.90 + Atomic<int32_t> mReallocCount;
1.91 + Atomic<int32_t> mFreeCount;
1.92 + Atomic<int32_t> mShareCount;
1.93 + Atomic<int32_t> mAdoptCount;
1.94 + Atomic<int32_t> mAdoptFreeCount;
1.95 + };
1.96 +static nsStringStats gStringStats;
1.97 +#define STRING_STAT_INCREMENT(_s) (gStringStats.m ## _s ## Count)++
1.98 +#else
1.99 +#define STRING_STAT_INCREMENT(_s)
1.100 +#endif
1.101 +
1.102 +// ---------------------------------------------------------------------------
1.103 +
1.104 +inline void
1.105 +ReleaseData( void* data, uint32_t flags )
1.106 + {
1.107 + if (flags & nsSubstring::F_SHARED)
1.108 + {
1.109 + nsStringBuffer::FromData(data)->Release();
1.110 + }
1.111 + else if (flags & nsSubstring::F_OWNED)
1.112 + {
1.113 + nsMemory::Free(data);
1.114 + STRING_STAT_INCREMENT(AdoptFree);
1.115 +#ifdef NS_BUILD_REFCNT_LOGGING
1.116 + // Treat this as destruction of a "StringAdopt" object for leak
1.117 + // tracking purposes.
1.118 + NS_LogDtor(data, "StringAdopt", 1);
1.119 +#endif // NS_BUILD_REFCNT_LOGGING
1.120 + }
1.121 + // otherwise, nothing to do.
1.122 + }
1.123 +
1.124 +// ---------------------------------------------------------------------------
1.125 +
1.126 +// XXX or we could make nsStringBuffer be a friend of nsTAString
1.127 +
1.128 +class nsAStringAccessor : public nsAString
1.129 + {
1.130 + private:
1.131 + nsAStringAccessor(); // NOT IMPLEMENTED
1.132 +
1.133 + public:
1.134 + char_type *data() const { return mData; }
1.135 + size_type length() const { return mLength; }
1.136 + uint32_t flags() const { return mFlags; }
1.137 +
1.138 + void set(char_type *data, size_type len, uint32_t flags)
1.139 + {
1.140 + ReleaseData(mData, mFlags);
1.141 + mData = data;
1.142 + mLength = len;
1.143 + mFlags = flags;
1.144 + }
1.145 + };
1.146 +
1.147 +class nsACStringAccessor : public nsACString
1.148 + {
1.149 + private:
1.150 + nsACStringAccessor(); // NOT IMPLEMENTED
1.151 +
1.152 + public:
1.153 + char_type *data() const { return mData; }
1.154 + size_type length() const { return mLength; }
1.155 + uint32_t flags() const { return mFlags; }
1.156 +
1.157 + void set(char_type *data, size_type len, uint32_t flags)
1.158 + {
1.159 + ReleaseData(mData, mFlags);
1.160 + mData = data;
1.161 + mLength = len;
1.162 + mFlags = flags;
1.163 + }
1.164 + };
1.165 +
1.166 +// ---------------------------------------------------------------------------
1.167 +
1.168 +void
1.169 +nsStringBuffer::AddRef()
1.170 + {
1.171 + ++mRefCount;
1.172 + STRING_STAT_INCREMENT(Share);
1.173 + NS_LOG_ADDREF(this, mRefCount, "nsStringBuffer", sizeof(*this));
1.174 + }
1.175 +
1.176 +void
1.177 +nsStringBuffer::Release()
1.178 + {
1.179 + int32_t count = --mRefCount;
1.180 + NS_LOG_RELEASE(this, count, "nsStringBuffer");
1.181 + if (count == 0)
1.182 + {
1.183 + STRING_STAT_INCREMENT(Free);
1.184 + free(this); // we were allocated with |malloc|
1.185 + }
1.186 + }
1.187 +
1.188 + /**
1.189 + * Alloc returns a pointer to a new string header with set capacity.
1.190 + */
1.191 +already_AddRefed<nsStringBuffer>
1.192 +nsStringBuffer::Alloc(size_t size)
1.193 + {
1.194 + NS_ASSERTION(size != 0, "zero capacity allocation not allowed");
1.195 + NS_ASSERTION(sizeof(nsStringBuffer) + size <= size_t(uint32_t(-1)) &&
1.196 + sizeof(nsStringBuffer) + size > size,
1.197 + "mStorageSize will truncate");
1.198 +
1.199 + nsStringBuffer *hdr =
1.200 + (nsStringBuffer *) malloc(sizeof(nsStringBuffer) + size);
1.201 + if (hdr)
1.202 + {
1.203 + STRING_STAT_INCREMENT(Alloc);
1.204 +
1.205 + hdr->mRefCount = 1;
1.206 + hdr->mStorageSize = size;
1.207 + NS_LOG_ADDREF(hdr, 1, "nsStringBuffer", sizeof(*hdr));
1.208 + }
1.209 + return dont_AddRef(hdr);
1.210 + }
1.211 +
1.212 +nsStringBuffer*
1.213 +nsStringBuffer::Realloc(nsStringBuffer* hdr, size_t size)
1.214 + {
1.215 + STRING_STAT_INCREMENT(Realloc);
1.216 +
1.217 + NS_ASSERTION(size != 0, "zero capacity allocation not allowed");
1.218 + NS_ASSERTION(sizeof(nsStringBuffer) + size <= size_t(uint32_t(-1)) &&
1.219 + sizeof(nsStringBuffer) + size > size,
1.220 + "mStorageSize will truncate");
1.221 +
1.222 + // no point in trying to save ourselves if we hit this assertion
1.223 + NS_ASSERTION(!hdr->IsReadonly(), "|Realloc| attempted on readonly string");
1.224 +
1.225 + // Treat this as a release and addref for refcounting purposes, since we
1.226 + // just asserted that the refcount is 1. If we don't do that, refcount
1.227 + // logging will claim we've leaked all sorts of stuff.
1.228 + NS_LOG_RELEASE(hdr, 0, "nsStringBuffer");
1.229 +
1.230 + hdr = (nsStringBuffer*) realloc(hdr, sizeof(nsStringBuffer) + size);
1.231 + if (hdr) {
1.232 + NS_LOG_ADDREF(hdr, 1, "nsStringBuffer", sizeof(*hdr));
1.233 + hdr->mStorageSize = size;
1.234 + }
1.235 +
1.236 + return hdr;
1.237 + }
1.238 +
1.239 +nsStringBuffer*
1.240 +nsStringBuffer::FromString(const nsAString& str)
1.241 + {
1.242 + const nsAStringAccessor* accessor =
1.243 + static_cast<const nsAStringAccessor*>(&str);
1.244 +
1.245 + if (!(accessor->flags() & nsSubstring::F_SHARED))
1.246 + return nullptr;
1.247 +
1.248 + return FromData(accessor->data());
1.249 + }
1.250 +
1.251 +nsStringBuffer*
1.252 +nsStringBuffer::FromString(const nsACString& str)
1.253 + {
1.254 + const nsACStringAccessor* accessor =
1.255 + static_cast<const nsACStringAccessor*>(&str);
1.256 +
1.257 + if (!(accessor->flags() & nsCSubstring::F_SHARED))
1.258 + return nullptr;
1.259 +
1.260 + return FromData(accessor->data());
1.261 + }
1.262 +
1.263 +void
1.264 +nsStringBuffer::ToString(uint32_t len, nsAString &str,
1.265 + bool aMoveOwnership)
1.266 + {
1.267 + char16_t* data = static_cast<char16_t*>(Data());
1.268 +
1.269 + nsAStringAccessor* accessor = static_cast<nsAStringAccessor*>(&str);
1.270 + NS_ASSERTION(data[len] == char16_t(0), "data should be null terminated");
1.271 +
1.272 + // preserve class flags
1.273 + uint32_t flags = accessor->flags();
1.274 + flags = (flags & 0xFFFF0000) | nsSubstring::F_SHARED | nsSubstring::F_TERMINATED;
1.275 +
1.276 + if (!aMoveOwnership) {
1.277 + AddRef();
1.278 + }
1.279 + accessor->set(data, len, flags);
1.280 + }
1.281 +
1.282 +void
1.283 +nsStringBuffer::ToString(uint32_t len, nsACString &str,
1.284 + bool aMoveOwnership)
1.285 + {
1.286 + char* data = static_cast<char*>(Data());
1.287 +
1.288 + nsACStringAccessor* accessor = static_cast<nsACStringAccessor*>(&str);
1.289 + NS_ASSERTION(data[len] == char(0), "data should be null terminated");
1.290 +
1.291 + // preserve class flags
1.292 + uint32_t flags = accessor->flags();
1.293 + flags = (flags & 0xFFFF0000) | nsCSubstring::F_SHARED | nsCSubstring::F_TERMINATED;
1.294 +
1.295 + if (!aMoveOwnership) {
1.296 + AddRef();
1.297 + }
1.298 + accessor->set(data, len, flags);
1.299 + }
1.300 +
1.301 +size_t
1.302 +nsStringBuffer::SizeOfIncludingThisMustBeUnshared(mozilla::MallocSizeOf aMallocSizeOf) const
1.303 + {
1.304 + NS_ASSERTION(!IsReadonly(),
1.305 + "shared StringBuffer in SizeOfIncludingThisMustBeUnshared");
1.306 + return aMallocSizeOf(this);
1.307 + }
1.308 +
1.309 +size_t
1.310 +nsStringBuffer::SizeOfIncludingThisIfUnshared(mozilla::MallocSizeOf aMallocSizeOf) const
1.311 + {
1.312 + if (!IsReadonly())
1.313 + {
1.314 + return SizeOfIncludingThisMustBeUnshared(aMallocSizeOf);
1.315 + }
1.316 + return 0;
1.317 + }
1.318 +
1.319 +size_t
1.320 +nsStringBuffer::SizeOfIncludingThisEvenIfShared(mozilla::MallocSizeOf aMallocSizeOf) const
1.321 + {
1.322 + return aMallocSizeOf(this);
1.323 + }
1.324 +
1.325 +// ---------------------------------------------------------------------------
1.326 +
1.327 +
1.328 + // define nsSubstring
1.329 +#include "string-template-def-unichar.h"
1.330 +#include "nsTSubstring.cpp"
1.331 +#include "string-template-undef.h"
1.332 +
1.333 + // define nsCSubstring
1.334 +#include "string-template-def-char.h"
1.335 +#include "nsTSubstring.cpp"
1.336 +#include "string-template-undef.h"
1.337 +
1.338 +// Check that internal and external strings have the same size.
1.339 +// See https://bugzilla.mozilla.org/show_bug.cgi?id=430581
1.340 +
1.341 +#include "prlog.h"
1.342 +#include "nsXPCOMStrings.h"
1.343 +
1.344 +static_assert(sizeof(nsStringContainer_base) == sizeof(nsSubstring),
1.345 + "internal and external strings must have the same size");
