xpcom/base/nsGZFileWriter.cpp@b8a032363ba2 (annotated)
xpcom/base/nsGZFileWriter.cpp
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| michael@0 | 2 | /* vim: set ts=8 sts=2 et sw=2 tw=80: */ |
| michael@0 | 3 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 4 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 5 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 6 | |
| michael@0 | 7 | #include "nsGZFileWriter.h" |
| michael@0 | 8 | #include "nsIFile.h" |
| michael@0 | 9 | #include "nsString.h" |
| michael@0 | 10 | #include "zlib.h" |
| michael@0 | 11 | |
| michael@0 | 12 | #ifdef XP_WIN |
| michael@0 | 13 | #include <io.h> |
| michael@0 | 14 | #define _dup dup |
| michael@0 | 15 | #else |
| michael@0 | 16 | #include <unistd.h> |
| michael@0 | 17 | #endif |
| michael@0 | 18 | |
| michael@0 | 19 | NS_IMPL_ISUPPORTS(nsGZFileWriter, nsIGZFileWriter) |
| michael@0 | 20 | |
| michael@0 | 21 | nsGZFileWriter::nsGZFileWriter() |
| michael@0 | 22 | : mInitialized(false) |
| michael@0 | 23 | , mFinished(false) |
| michael@0 | 24 | {} |
| michael@0 | 25 | |
| michael@0 | 26 | nsGZFileWriter::~nsGZFileWriter() |
| michael@0 | 27 | { |
| michael@0 | 28 | if (mInitialized && !mFinished) { |
| michael@0 | 29 | Finish(); |
| michael@0 | 30 | } |
| michael@0 | 31 | } |
| michael@0 | 32 | |
| michael@0 | 33 | NS_IMETHODIMP |
| michael@0 | 34 | nsGZFileWriter::Init(nsIFile* aFile) |
| michael@0 | 35 | { |
| michael@0 | 36 | if (NS_WARN_IF(mInitialized) || |
| michael@0 | 37 | NS_WARN_IF(mFinished)) |
| michael@0 | 38 | return NS_ERROR_FAILURE; |
| michael@0 | 39 | |
| michael@0 | 40 | // Get a FILE out of our nsIFile. Convert that into a file descriptor which |
| michael@0 | 41 | // gzip can own. Then close our FILE, leaving only gzip's fd open. |
| michael@0 | 42 | |
| michael@0 | 43 | FILE* file; |
| michael@0 | 44 | nsresult rv = aFile->OpenANSIFileDesc("wb", &file); |
| michael@0 | 45 | if (NS_WARN_IF(NS_FAILED(rv))) |
| michael@0 | 46 | return rv; |
| michael@0 | 47 | |
| michael@0 | 48 | mGZFile = gzdopen(dup(fileno(file)), "wb"); |
| michael@0 | 49 | fclose(file); |
| michael@0 | 50 | |
| michael@0 | 51 | // gzdopen returns nullptr on error. |
| michael@0 | 52 | if (NS_WARN_IF(!mGZFile)) |
| michael@0 | 53 | return NS_ERROR_FAILURE; |
| michael@0 | 54 | |
| michael@0 | 55 | mInitialized = true; |
| michael@0 | 56 | |
| michael@0 | 57 | return NS_OK; |
| michael@0 | 58 | } |
| michael@0 | 59 | |
| michael@0 | 60 | NS_IMETHODIMP |
| michael@0 | 61 | nsGZFileWriter::Write(const nsACString& aStr) |
| michael@0 | 62 | { |
| michael@0 | 63 | if (NS_WARN_IF(!mInitialized) || |
| michael@0 | 64 | NS_WARN_IF(mFinished)) |
| michael@0 | 65 | return NS_ERROR_FAILURE; |
| michael@0 | 66 | |
| michael@0 | 67 | // gzwrite uses a return value of 0 to indicate failure. Otherwise, it |
| michael@0 | 68 | // returns the number of uncompressed bytes written. To ensure we can |
| michael@0 | 69 | // distinguish between success and failure, don't call gzwrite when we have 0 |
| michael@0 | 70 | // bytes to write. |
| michael@0 | 71 | if (aStr.IsEmpty()) { |
| michael@0 | 72 | return NS_OK; |
| michael@0 | 73 | } |
| michael@0 | 74 | |
| michael@0 | 75 | // gzwrite never does a short write -- that is, the return value should |
| michael@0 | 76 | // always be either 0 or aStr.Length(), and we shouldn't have to call it |
| michael@0 | 77 | // multiple times in order to get it to read the whole buffer. |
| michael@0 | 78 | int rv = gzwrite(mGZFile, aStr.BeginReading(), aStr.Length()); |
| michael@0 | 79 | if (NS_WARN_IF(rv != static_cast<int>(aStr.Length()))) |
| michael@0 | 80 | return NS_ERROR_FAILURE; |
| michael@0 | 81 | |
| michael@0 | 82 | return NS_OK; |
| michael@0 | 83 | } |
| michael@0 | 84 | |
| michael@0 | 85 | NS_IMETHODIMP |
| michael@0 | 86 | nsGZFileWriter::Finish() |
| michael@0 | 87 | { |
| michael@0 | 88 | if (NS_WARN_IF(!mInitialized) || |
| michael@0 | 89 | NS_WARN_IF(mFinished)) |
| michael@0 | 90 | return NS_ERROR_FAILURE; |
| michael@0 | 91 | |
| michael@0 | 92 | mFinished = true; |
| michael@0 | 93 | gzclose(mGZFile); |
| michael@0 | 94 | |
| michael@0 | 95 | // Ignore errors from gzclose; it's not like there's anything we can do about |
| michael@0 | 96 | // it, at this point! |
| michael@0 | 97 | return NS_OK; |
| michael@0 | 98 | } |
