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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef nsGZFileWriter_h
#define nsGZFileWriter_h
#include "nsISupportsImpl.h"
#include "zlib.h"
#include "nsDependentString.h"
#include <stdio.h>
/**
* A simple class for writing to a .gz file.
*
* Note that the file that this interface produces has a different format than
* what you'd get if you compressed your data as a gzip stream and dumped the
* result to a file.
*
* The standard gunzip tool cannot decompress a raw gzip stream, but can handle
* the files produced by this interface.
*/
class nsGZFileWriter final {
virtual ~nsGZFileWriter();
public:
enum Operation { Append, Create };
explicit nsGZFileWriter(Operation aMode = Create);
NS_INLINE_DECL_REFCOUNTING(nsGZFileWriter)
/**
* Initialize this object. We'll write our gzip'ed data to the given file,
* overwriting its contents if the file exists.
*
* Init() will return an error if called twice. It's an error to call any
* other method on this interface without first calling Init().
*/
[[nodiscard]] nsresult Init(nsIFile* aFile);
/**
* Alternate version of Init() for use when the file is already opened;
* e.g., with a FileDescriptor passed over IPC.
*/
[[nodiscard]] nsresult InitANSIFileDesc(FILE* aFile);
/**
* Write the given string to the file.
*/
[[nodiscard]] nsresult Write(const nsACString& aStr);
/**
* Write |length| bytes of |str| to the file.
*/
[[nodiscard]] nsresult Write(const char* aStr, uint32_t aLen) {
return Write(nsDependentCSubstring(aStr, aLen));
}
/**
* Close this nsGZFileWriter. This method will be run when the underlying
* object is destroyed, so it's not strictly necessary to explicitly call it
* from your code.
*
* It's an error to call this method twice, and it's an error to call Write()
* after Finish() has been called.
*/
nsresult Finish();
private:
Operation mMode;
bool mInitialized;
bool mFinished;
gzFile mGZFile;
};
#endif