xpcom/io/nsScriptableInputStream.cpp@97036ab72558 (annotated)
xpcom/io/nsScriptableInputStream.cpp
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ |
| michael@0 | 2 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 4 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | #include "nsScriptableInputStream.h" |
| michael@0 | 7 | #include "nsMemory.h" |
| michael@0 | 8 | #include "nsString.h" |
| michael@0 | 9 | |
| michael@0 | 10 | NS_IMPL_ISUPPORTS(nsScriptableInputStream, nsIScriptableInputStream) |
| michael@0 | 11 | |
| michael@0 | 12 | // nsIScriptableInputStream methods |
| michael@0 | 13 | NS_IMETHODIMP |
| michael@0 | 14 | nsScriptableInputStream::Close(void) { |
| michael@0 | 15 | if (!mInputStream) return NS_ERROR_NOT_INITIALIZED; |
| michael@0 | 16 | return mInputStream->Close(); |
| michael@0 | 17 | } |
| michael@0 | 18 | |
| michael@0 | 19 | NS_IMETHODIMP |
| michael@0 | 20 | nsScriptableInputStream::Init(nsIInputStream *aInputStream) { |
| michael@0 | 21 | if (!aInputStream) return NS_ERROR_NULL_POINTER; |
| michael@0 | 22 | mInputStream = aInputStream; |
| michael@0 | 23 | return NS_OK; |
| michael@0 | 24 | } |
| michael@0 | 25 | |
| michael@0 | 26 | NS_IMETHODIMP |
| michael@0 | 27 | nsScriptableInputStream::Available(uint64_t *_retval) { |
| michael@0 | 28 | if (!mInputStream) return NS_ERROR_NOT_INITIALIZED; |
| michael@0 | 29 | return mInputStream->Available(_retval); |
| michael@0 | 30 | } |
| michael@0 | 31 | |
| michael@0 | 32 | NS_IMETHODIMP |
| michael@0 | 33 | nsScriptableInputStream::Read(uint32_t aCount, char **_retval) { |
| michael@0 | 34 | nsresult rv = NS_OK; |
| michael@0 | 35 | uint64_t count64 = 0; |
| michael@0 | 36 | char *buffer = nullptr; |
| michael@0 | 37 | |
| michael@0 | 38 | if (!mInputStream) return NS_ERROR_NOT_INITIALIZED; |
| michael@0 | 39 | |
| michael@0 | 40 | rv = mInputStream->Available(&count64); |
| michael@0 | 41 | if (NS_FAILED(rv)) return rv; |
| michael@0 | 42 | |
| michael@0 | 43 | // bug716556 - Ensure count+1 doesn't overflow |
| michael@0 | 44 | uint32_t count = XPCOM_MIN((uint32_t)XPCOM_MIN<uint64_t>(count64, aCount), UINT32_MAX - 1); |
| michael@0 | 45 | buffer = (char*)moz_malloc(count+1); // make room for '\0' |
| michael@0 | 46 | if (!buffer) return NS_ERROR_OUT_OF_MEMORY; |
| michael@0 | 47 | |
| michael@0 | 48 | rv = ReadHelper(buffer, count); |
| michael@0 | 49 | if (NS_FAILED(rv)) { |
| michael@0 | 50 | nsMemory::Free(buffer); |
| michael@0 | 51 | return rv; |
| michael@0 | 52 | } |
| michael@0 | 53 | |
| michael@0 | 54 | buffer[count] = '\0'; |
| michael@0 | 55 | *_retval = buffer; |
| michael@0 | 56 | return NS_OK; |
| michael@0 | 57 | } |
| michael@0 | 58 | |
| michael@0 | 59 | NS_IMETHODIMP |
| michael@0 | 60 | nsScriptableInputStream::ReadBytes(uint32_t aCount, nsACString &_retval) { |
| michael@0 | 61 | if (!mInputStream) { |
| michael@0 | 62 | return NS_ERROR_NOT_INITIALIZED; |
| michael@0 | 63 | } |
| michael@0 | 64 | |
| michael@0 | 65 | _retval.SetLength(aCount); |
| michael@0 | 66 | if (_retval.Length() != aCount) { |
| michael@0 | 67 | return NS_ERROR_OUT_OF_MEMORY; |
| michael@0 | 68 | } |
| michael@0 | 69 | |
| michael@0 | 70 | char *ptr = _retval.BeginWriting(); |
| michael@0 | 71 | nsresult rv = ReadHelper(ptr, aCount); |
| michael@0 | 72 | if (NS_FAILED(rv)) { |
| michael@0 | 73 | _retval.Truncate(); |
| michael@0 | 74 | } |
| michael@0 | 75 | return rv; |
| michael@0 | 76 | } |
| michael@0 | 77 | |
| michael@0 | 78 | nsresult |
| michael@0 | 79 | nsScriptableInputStream::ReadHelper(char* aBuffer, uint32_t aCount) |
| michael@0 | 80 | { |
| michael@0 | 81 | uint32_t totalBytesRead = 0; |
| michael@0 | 82 | while (1) { |
| michael@0 | 83 | uint32_t bytesRead; |
| michael@0 | 84 | nsresult rv = mInputStream->Read(aBuffer + totalBytesRead, |
| michael@0 | 85 | aCount - totalBytesRead, |
| michael@0 | 86 | &bytesRead); |
| michael@0 | 87 | if (NS_FAILED(rv)) { |
| michael@0 | 88 | return rv; |
| michael@0 | 89 | } |
| michael@0 | 90 | |
| michael@0 | 91 | totalBytesRead += bytesRead; |
| michael@0 | 92 | if (totalBytesRead == aCount) { |
| michael@0 | 93 | break; |
| michael@0 | 94 | } |
| michael@0 | 95 | |
| michael@0 | 96 | // If we have read zero bytes, we have hit EOF. |
| michael@0 | 97 | if (bytesRead == 0) { |
| michael@0 | 98 | return NS_ERROR_FAILURE; |
| michael@0 | 99 | } |
| michael@0 | 100 | |
| michael@0 | 101 | } |
| michael@0 | 102 | return NS_OK; |
| michael@0 | 103 | } |
| michael@0 | 104 | |
| michael@0 | 105 | nsresult |
| michael@0 | 106 | nsScriptableInputStream::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult) { |
| michael@0 | 107 | if (aOuter) return NS_ERROR_NO_AGGREGATION; |
| michael@0 | 108 | |
| michael@0 | 109 | nsScriptableInputStream *sis = new nsScriptableInputStream(); |
| michael@0 | 110 | if (!sis) return NS_ERROR_OUT_OF_MEMORY; |
| michael@0 | 111 | |
| michael@0 | 112 | NS_ADDREF(sis); |
| michael@0 | 113 | nsresult rv = sis->QueryInterface(aIID, aResult); |
| michael@0 | 114 | NS_RELEASE(sis); |
| michael@0 | 115 | return rv; |
| michael@0 | 116 | } |
