Ensure that only DataStruct::mData + mDataLen, XOR
DataStruct::mCacheFD is used.
(Previously it was possible that all of these members were populated,
which is a waste of memory.)
The effect of this change is visible when SetTransferData is called
multiple times with the same flavor, but with one below the threshold
for storing in-memory, and the other above (=store in a file).
MozReview-Commit-ID: 4UlkKAYsjf
The cache file is never directly exposed to consumers of DataStruct,
so it does not make sense to keep the clipboardcache file around
forever.
The only change in this commit is to switch from using a filename to
using a file descriptor. In the destructor, the FD is explicitly closed
(which releases the file data). nsAnonymousTemporaryFile takes care
of removing the file when the destructor is not called (e.g. crashes).
Previously, the clipboard cache was stored in a file called:
TmpD/clipboardcache-N
As of this commit, the clipboard cache is stored at:
TmpD/mozilla-temp-randomN (macOS and Linux)
TmpD/mozilla-temp-files/mozilla-temp-randomN (Windows)
(see xpcom/io/nsAnonymousTemporaryFile.{h,cpp} for more details)
To verify that these files are really gone:
1. Create a document with 500k+ characters, open it in Firefox.
2. Copy its content - this will trigger the clipboard cache.
3. Look for the open file descriptor of the deleted file:
( macOS and Linux: )
lsof +L1 | grep mozilla-temp
4. Copy anything (under the 500k threshold), or quit/kill Firefox.
5. Repeat step 3 and observe that the number of file descriptors
has decreased.
MozReview-Commit-ID: 85GlKQrNUl5
Ensure that only DataStruct::mData + mDataLen, XOR
DataStruct::mCacheFD is used.
(Previously it was possible that all of these members were populated,
which is a waste of memory.)
The effect of this change is visible when SetTransferData is called
multiple times with the same flavor, but with one below the threshold
for storing in-memory, and the other above (=store in a file).
MozReview-Commit-ID: 4UlkKAYsjf
The cache file is never directly exposed to consumers of DataStruct,
so it does not make sense to keep the clipboardcache file around
forever.
The only change in this commit is to switch from using a filename to
using a file descriptor. In the destructor, the FD is explicitly closed
(which releases the file data). nsAnonymousTemporaryFile takes care
of removing the file when the destructor is not called (e.g. crashes).
Previously, the clipboard cache was stored in a file called:
TmpD/clipboardcache-N
As of this commit, the clipboard cache is stored at:
TmpD/mozilla-temp-randomN (macOS and Linux)
TmpD/mozilla-temp-files/mozilla-temp-randomN (Windows)
(see xpcom/io/nsAnonymousTemporaryFile.{h,cpp} for more details)
To verify that these files are really gone:
1. Create a document with 500k+ characters, open it in Firefox.
2. Copy its content - this will trigger the clipboard cache.
3. Look for the open file descriptor of the deleted file:
( macOS and Linux: )
lsof +L1 | grep mozilla-temp
4. Copy anything (under the 500k threshold), or quit/kill Firefox.
5. Repeat step 3 and observe that the number of file descriptors
has decreased.
MozReview-Commit-ID: 85GlKQrNUl5
This is straightforward, with only two notable things.
- `#include "nsXPIDLString.h" is replaced with `#include "nsString.h"`
throughout, because all nsXPIDLString.h did was include nsString.h. The
exception is for files which already include nsString.h, in which case the
patch just removes the nsXPIDLString.h inclusion.
- The patch removes the |xpidl_string| gtest, but improves the |voided| test to
cover some of its ground, e.g. testing Adopt(nullptr).
This converts |nsITransferable.flavorsTransferableCanExport| and
|nsITransferable.flavorsTransferableCanImport| to return a |nsIArray|.
|nsIFormatConverter.getInputDataFlavors| and
|nsIFormatConverter.getOutputDataFlavors| are updated as well.
This patch mitigates violation of private browsing disk access. The DataStruct API and implementation is modified to obey private browsing design when used by objects such as nsTransferable (during clipboard data caching for example.)
Without this patch, a user is misled by use of private browsing when copying (or in some case just selecting) large blocks of text. A condition (presently hard coded at one million bytes kLargeDatasetSize) produces a cache file on disk regardless of whether private browsing is in use. This violates Mozilla's design (documented online at https://support.mozilla.org/kb/private-browsing-browse-web-without-saving-info/ and https://wiki.mozilla.org/PrivateBrowsing) This patch simply corrects the violation, discovered and resolved by the Tor Browser community.
