From c3b0ff9c7a62d837fcd673114aabc9989bfc2a0d Mon Sep 17 00:00:00 2001 From: Vadim Zeitlin Date: Mon, 20 Jul 1998 22:26:39 +0000 Subject: [PATCH] bug in wxFileConfig::DeleteEntry/Group corrected git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@318 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775 --- src/common/fileconf.cpp | 208 +++++++++++++++++++++++++++++++++------- 1 file changed, 176 insertions(+), 32 deletions(-) diff --git a/src/common/fileconf.cpp b/src/common/fileconf.cpp index d4a7cf6152..d0c6ac8062 100644 --- a/src/common/fileconf.cpp +++ b/src/common/fileconf.cpp @@ -512,10 +512,41 @@ bool wxFileConfig::Write(const char *szKey, const char *szValue) { PathChanger path(this, szKey); - ConfigEntry *pEntry = m_pCurrentGroup->FindEntry(path.Name()); - if ( pEntry == NULL ) - pEntry = m_pCurrentGroup->AddEntry(path.Name()); - pEntry->SetValue(szValue); + wxString strName = path.Name(); + if ( strName.IsEmpty() ) { + // setting the value of a group is an error + wxASSERT_MSG( IsEmpty(szValue), "can't set value of a group!" ); + + // ... except if it's empty in which case it's a way to force it's creation + m_pCurrentGroup->SetDirty(); + + // this will add a line for this group if it didn't have it before + (void)m_pCurrentGroup->GetGroupLine(); + } + else { + // writing an entry + + // check that the name is reasonable + if ( strName[0u] == APPCONF_IMMUTABLE_PREFIX ) { + wxLogError(_("Entry name can't start with '%c'."), + APPCONF_IMMUTABLE_PREFIX); + return FALSE; + } + + for ( const char *pc = strName; *pc != '\0'; pc++ ) { + if ( !IsValid(*pc) ) { + wxLogError(_("Character '%c' is invalid in a config entry name."), + *pc); + return FALSE; + } + } + + ConfigEntry *pEntry = m_pCurrentGroup->FindEntry(strName); + if ( pEntry == NULL ) + pEntry = m_pCurrentGroup->AddEntry(strName); + + pEntry->SetValue(szValue); + } return TRUE; } @@ -650,16 +681,18 @@ void wxFileConfig::LineListRemove(LineList *pLine) { LineList *pPrev = pLine->Prev(), *pNext = pLine->Next(); - if ( pPrev == NULL ) { - // deleting the first entry + + // first entry? + if ( pPrev == NULL ) m_linesHead = pNext; - } - else { - // not the first entry + else pPrev->SetNext(pNext); - } - pNext->SetPrev(pPrev); + // last entry? + if ( pNext == NULL ) + m_linesTail = pPrev; + else + pNext->SetPrev(pPrev); delete pLine; } @@ -687,8 +720,9 @@ wxFileConfig::ConfigGroup::ConfigGroup(wxFileConfig::ConfigGroup *pParent, { m_pConfig = pConfig; m_pParent = pParent; - m_pLine = NULL; m_bDirty = FALSE; + m_pLine = NULL; + m_pLastEntry = NULL; m_pLastGroup = NULL; } @@ -718,17 +752,52 @@ void wxFileConfig::ConfigGroup::SetLine(LineList *pLine) m_pLine = pLine; } -// return the line which contains "[our name]" +/* + This is a bit complicated, so let me explain it in details. All lines that + were read from the local file (the only one we will ever modify) are stored + in a (doubly) linked list. Our problem is to know at which position in this + list should we insert the new entries/subgroups. To solve it we keep three + variables for each group: m_pLine, m_pLastEntry and m_pLastGroup. + + m_pLine points to the line containing "[group_name]" + m_pLastEntry points to the last entry of this group in the local file. + m_pLastGroup subgroup + + Initially, they're NULL all three. When the group (an entry/subgroup) is read + from the local file, the corresponding variable is set. However, if the group + was read from the global file and then modified or created by the application + these variables are still NULL and we need to create the corresponding lines. + See the following functions (and comments preceding them) for the details of + how we do it. + + Also, when our last entry/group are deleted we need to find the new last + element - the code in DeleteEntry/Subgroup does this by backtracking the list + of lines until it either founds an entry/subgroup (and this is the new last + element) or the m_pLine of the group, in which case there are no more entries + (or subgroups) left and m_pLast becomes NULL. + + NB: This last problem could be avoided for entries if we added new entries + immediately after m_pLine, but in this case the entries would appear + backwards in the config file (OTOH, it's not that important) and as we + would still need to do it for the subgroups the code wouldn't have been + significantly less complicated. + */ + +// Return the line which contains "[our name]". If we're still not in the list, +// add our line to it immediately after the last line of our parent group if we +// have it or in the very beginning if we're the root group. wxFileConfig::LineList *wxFileConfig::ConfigGroup::GetGroupLine() { if ( m_pLine == NULL ) { + ConfigGroup *pParent = Parent(); + // this group wasn't present in local config file, add it now - if ( Parent() != NULL ) { + if ( pParent != NULL ) { wxString strFullName; strFullName << "[" << GetFullName().c_str() + 1 << "]"; // +1: no '/' m_pLine = m_pConfig->LineListInsert(strFullName, - Parent()->GetLastGroupLine()); - Parent()->SetLastGroup(this); + pParent->GetLastGroupLine()); + pParent->SetLastGroup(this); // we're surely after all the others } else { // we return NULL, so that LineListInsert() will insert us in the @@ -739,25 +808,27 @@ wxFileConfig::LineList *wxFileConfig::ConfigGroup::GetGroupLine() return m_pLine; } -// return the last line belonging to the subgroups of this group -// (after which we can add a new subgroup) +// Return the last line belonging to the subgroups of this group (after which +// we can add a new subgroup), if we don't have any subgroups or entries our +// last line is the group line (m_pLine) itself. wxFileConfig::LineList *wxFileConfig::ConfigGroup::GetLastGroupLine() { // if we have any subgroups, our last line is the last line of the last // subgroup - if ( m_pLastGroup != NULL ) - return m_pLastGroup->GetLastGroupLine(); + if ( m_pLastGroup != NULL ) { + wxFileConfig::LineList *pLine = m_pLastGroup->GetLastGroupLine(); - // if we have any entries, our last line is the last entry - if ( m_pLastEntry != NULL ) - return m_pLastEntry->GetLine(); + wxASSERT( pLine != NULL ); // last group must have !NULL associated line + return pLine; + } - // nothing at all: last line is the first one - return GetGroupLine(); + // no subgroups, so the last line is the line of thelast entry (if any) + return GetLastEntryLine(); } -// return the last line belonging to the entries of this group -// (after which we can add a new entry) +// return the last line belonging to the entries of this group (after which +// we can add a new entry), if we don't have any entries we will add the new +// one immediately after the group line itself. wxFileConfig::LineList *wxFileConfig::ConfigGroup::GetLastEntryLine() { if ( m_pLastEntry != NULL ) { @@ -767,7 +838,7 @@ wxFileConfig::LineList *wxFileConfig::ConfigGroup::GetLastEntryLine() return pLine; } - // no entrues: insert after the group header + // no entries: insert after the group header return GetGroupLine(); } @@ -880,6 +951,13 @@ wxFileConfig::ConfigGroup::AddSubgroup(const wxString& strName) // delete an item // ---------------------------------------------------------------------------- +/* + The delete operations are _very_ slow if we delete the last item of this + group (see comments before GetXXXLineXXX functions for more details), + so it's much better to start with the first entry/group if we want to + delete several of them. + */ + bool wxFileConfig::ConfigGroup::DeleteSubgroup(const char *szName) { ConfigGroup *pGroup = FindSubgroup(szName); @@ -894,8 +972,41 @@ bool wxFileConfig::ConfigGroup::DeleteSubgroup(const char *szName) } LineList *pLine = pGroup->m_pLine; - if ( pLine != NULL ) + if ( pLine != NULL ) { + // notice that we may do this test inside the previous "if" because the + // last entry's line is surely !NULL + if ( pGroup == m_pLastGroup ) { + // our last entry is being deleted - find the last one which stays + wxASSERT( m_pLine != NULL ); // we have a subgroup with !NULL pLine... + + // go back until we find a subgroup or reach the group's line + ConfigGroup *pNewLast = NULL; + uint n, nSubgroups = m_aSubgroups.Count(); + for ( LineList *pl = pLine->Prev(); pl != m_pLine; pl = pl->Prev() ) { + // is it our subgroup? + for ( n = 0; (pNewLast == NULL) && (n < nSubgroups); n++ ) { + // do _not_ call GetGroupLine! we don't want to add it to the local + // file if it's not already there + if ( m_aSubgroups[n]->m_pLine == m_pLine ) + pNewLast = m_aSubgroups[n]; + } + + if ( pNewLast != NULL ) // found? + break; + } + + if ( pl == m_pLine ) { + wxASSERT( !pNewLast ); // how comes it has the same line as we? + + // we've reached the group line without finding any subgroups + m_pLastGroup = NULL; + } + else + m_pLastGroup = pNewLast; + } + m_pConfig->LineListRemove(pLine); + } SetDirty(); @@ -908,13 +1019,44 @@ bool wxFileConfig::ConfigGroup::DeleteSubgroup(const char *szName) bool wxFileConfig::ConfigGroup::DeleteEntry(const char *szName) { ConfigEntry *pEntry = FindEntry(szName); - if ( pEntry == NULL ) - return FALSE; + wxCHECK( pEntry != NULL, FALSE ); // deleting non existing item? LineList *pLine = pEntry->GetLine(); - if ( pLine != NULL ) + if ( pLine != NULL ) { + // notice that we may do this test inside the previous "if" because the + // last entry's line is surely !NULL + if ( pEntry == m_pLastEntry ) { + // our last entry is being deleted - find the last one which stays + wxASSERT( m_pLine != NULL ); // if we have an entry with !NULL pLine... + + // go back until we find another entry or reach the group's line + ConfigEntry *pNewLast = NULL; + uint n, nEntries = m_aEntries.Count(); + for ( LineList *pl = pLine->Prev(); pl != m_pLine; pl = pl->Prev() ) { + // is it our subgroup? + for ( n = 0; (pNewLast == NULL) && (n < nEntries); n++ ) { + if ( m_aEntries[n]->GetLine() == m_pLine ) + pNewLast = m_aEntries[n]; + } + + if ( pNewLast != NULL ) // found? + break; + } + + if ( pl == m_pLine ) { + wxASSERT( !pNewLast ); // how comes it has the same line as we? + + // we've reached the group line without finding any subgroups + m_pLastEntry = NULL; + } + else + m_pLastEntry = pNewLast; + } + m_pConfig->LineListRemove(pLine); + } + // we must be written back for the changes to be saved SetDirty(); m_aEntries.Remove(pEntry); @@ -945,6 +1087,8 @@ wxFileConfig::ConfigEntry::ConfigEntry(wxFileConfig::ConfigGroup *pParent, int nLine) : m_strName(strName) { + wxASSERT( !strName.IsEmpty() ); + m_pParent = pParent; m_nLine = nLine; m_pLine = NULL; -- 2.47.2