Amebis/wxWidgets
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fix dereferencing invalid iterator in wxMemoryFSHandlerBase

Browse Source 
Don't assume that m_findIter is always valid initially, i.e. after
FindFirst() is called, as this is not the case if the memory FS is
empty, i.e. which no files had been added to it yet.

This also allows to simplify the iteration logic, as we don't need to
check m_findArgument (which, in turn, obviates the need to clear it when
we reach the end of the iteration) and can just use m_findIter directly.

Closes #18416.
This commit is contained in:
Vadim Zeitlin
2019-06-10 18:07:57 +02:00
parent 3ff6647886
commit 39bab48dee
2 changed files with 7 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
include/wx/fs_mem.h
View File

@@ -64,11 +64,10 @@ protected:
// the file name currently being searched for, i.e. the argument of the // the file name currently being searched for, i.e. the argument of the
// last FindFirst() call or empty string if FindFirst() hasn't been called // last FindFirst() call or empty string if FindFirst() hasn't been called
// yet or FindNext() didn't find anything // yet
wxString m_findArgument; wxString m_findArgument;
// iterator into m_Hash used by FindFirst/Next(), possibly m_Hash.end() or // iterator into m_Hash used by FindFirst/Next(), possibly m_Hash.end()
// even invalid (can only be used when m_findArgument is not empty)
wxMemoryFSHash::const_iterator m_findIter; wxMemoryFSHash::const_iterator m_findIter;
}; };

16
src/common/fs_mem.cpp
View File

@@ -147,22 +147,16 @@ wxString wxMemoryFSHandlerBase::FindFirst(const wxString& url, int flags)
wxString wxMemoryFSHandlerBase::FindNext() wxString wxMemoryFSHandlerBase::FindNext()
{ {
// m_findArgument is used to indicate that search is in progress, we reset while ( m_findIter != m_Hash.end() )
// it to empty string after iterating over all elements
while ( !m_findArgument.empty() )
{ {
// test for the match before (possibly) clearing m_findArgument below const wxString& path = m_findIter->first;
const bool found = m_findIter->first.Matches(m_findArgument);
// advance m_findIter first as we need to do it anyhow, whether it // advance m_findIter first as we need to do it anyhow, whether it
// matches or not // matches or not
const wxMemoryFSHash::const_iterator current = m_findIter; ++m_findIter;
if ( ++m_findIter == m_Hash.end() ) if ( path.Matches(m_findArgument) )
m_findArgument.clear(); return "memory:" + path;
if ( found )
return "memory:" + current->first;
} }
return wxString(); return wxString();