Keep last file positions in last-use ordering

Using a map would sort the elements in alphabetic ordering, which
means that when the number of elements is larger than 100, the wrong
elements get pruned.

This commit uses a list instead. Searching an item needs linear time,
but this should not be a problem for a list with less than 100
elements.

Fixes bug #10310.

(cherry picked from commit 58d22e0c6edab4cb68af63d3ccaafcb875be995d)

diff --git a/src/BufferView.cpp b/src/BufferView.cpp
index 68d2c83f00bfecc543ea14d8d56f889ca7eecef6..d3d5dffea8027d4c8c4ec3f10096626bf63f47fb 100644 (file)
--- a/src/BufferView.cpp
+++ b/src/BufferView.cpp
@@ -351,9 +351,10 @@ BufferView::~BufferView()
        // That is to say, if a cursor is in a nested inset, it will be
        // restore to the left of the top level inset.
        LastFilePosSection::FilePos fp;
+       fp.file = buffer_.fileName();
        fp.pit = d->cursor_.bottom().pit();
        fp.pos = d->cursor_.bottom().pos();
-       theSession().lastFilePos().save(buffer_.fileName(), fp);
+       theSession().lastFilePos().save(fp);
 
        if (d->last_inset_)
                d->last_inset_->setMouseHover(this, false);

diff --git a/src/Session.cpp b/src/Session.cpp
index eb0fc64829f6a1226e82491284060490c30174bb..394788381ee38bbc6d78a33912677cf02a99c2d3 100644 (file)
--- a/src/Session.cpp
+++ b/src/Session.cpp
@@ -196,10 +196,10 @@ void LastFilePosSection::read(istream & is)
                        getline(itmp, fname);
                        if (!FileName::isAbsolute(fname))
                                continue;
-                       FileName const file(fname);
-                       if (file.exists() && !file.isDirectory()
+                       filepos.file = FileName(fname);
+                       if (filepos.file.exists() && !filepos.file.isDirectory()
                            && lastfilepos.size() < num_lastfilepos)
-                               lastfilepos[file] = filepos;
+                               lastfilepos.push_back(filepos);
                        else
                                LYXERR(Debug::INIT, "LyX: Warning: Ignore pos of last file: " << fname);
                } catch (...) {
@@ -212,26 +212,34 @@ void LastFilePosSection::read(istream & is)
 void LastFilePosSection::write(ostream & os) const
 {
        os << '\n' << sec_lastfilepos << '\n';
-       for (FilePosMap::const_iterator file = lastfilepos.begin();
-               file != lastfilepos.end(); ++file) {
-               os << file->second.pit << ", " << file->second.pos << ", "
-                  << file->first << '\n';
-       }
+       for (auto const & file_p : lastfilepos)
+               os << file_p.pit << ", " << file_p.pos << ", " << file_p.file << '\n';
 }
 
 
-void LastFilePosSection::save(FileName const & fname, FilePos const & pos)
+void LastFilePosSection::save(FilePos const & pos)
 {
-       lastfilepos[fname] = pos;
+       // Remove element if it was already present. Iterating should
+       // not be a problem since the list is small (<100 elements).
+       for (FilePosList::const_iterator it = lastfilepos.begin();
+            it != lastfilepos.end(); ++it)
+               if (it->file == pos.file) {
+                       lastfilepos.erase(it);
+                       break;
+               }
+
+       // insert new element at front.
+       lastfilepos.push_front(pos);
 }
 
 
 LastFilePosSection::FilePos LastFilePosSection::load(FileName const & fname) const
 {
-       FilePosMap::const_iterator entry = lastfilepos.find(fname);
-       // Has position information, return it.
-       if (entry != lastfilepos.end())
-               return entry->second;
+       for (auto & fp : lastfilepos)
+               if (fp.file == fname)
+                       // Has position information, return it.
+                       return fp;
+
        // Not found, return the first paragraph
        return FilePos();
 }

diff --git a/src/Session.h b/src/Session.h
index 31ffee8841bab4cb2ab98945058140ddbba2c8e9..65bf19de1342be91495ff0c51c33813d25a191a8 100644 (file)
--- a/src/Session.h
+++ b/src/Session.h
@@ -16,7 +16,7 @@
 #include "support/FileName.h"
 #include "support/types.h"
 
-#include <map>
+#include <list>
 #include <string>
 #include <vector>
 
@@ -148,12 +148,13 @@ public:
        ///
        struct FilePos {
                FilePos() : pit(0), pos(0) {}
+               support::FileName file;
                pit_type pit;
                pos_type pos;
        };
 
        ///
-       typedef std::map<support::FileName, FilePos> FilePosMap;
+       typedef std::list<FilePos> FilePosList;
 
 public:
        ///
@@ -165,13 +166,12 @@ public:
        ///
        void write(std::ostream & os) const;
 
-       /** add cursor position to the fname entry in the filepos map
-           @param fname file entry for which to save position information
-           @param pos position of the cursor when the BufferView is closed.
+       /** add cursor position to the fname entry in the filepos list
+           @param pos file name and position of the cursor when the BufferView is closed.
        */
-       void save(support::FileName const & fname, FilePos const & pos);
+       void save(FilePos const & pos);
 
-       /** load saved cursor position from the fname entry in the filepos map
+       /** load saved cursor position from the fname entry in the filepos list
            @param fname file entry for which to load position information
        */
        FilePos load(support::FileName const & fname) const;
@@ -181,8 +181,8 @@ private:
        unsigned int const num_lastfilepos;
 
 
-       /// a map of file positions
-       FilePosMap lastfilepos;
+       /// a list of file positions
+       FilePosList lastfilepos;
 };
 
 

diff --git a/status.23x b/status.23x
index ca88d6686ce9f4489a1028aaed9773a6ead707f8..23bd3edb119693c128ae1d08de0c5d0ff6f83e08 100644 (file)
--- a/status.23x
+++ b/status.23x
@@ -154,6 +154,9 @@ What's new
 
 - Avoid future crashes with math split insets by adding an extra test.
 
+- Properly remember cursor posoiton when many files have been opened
+  (bug 10310).
+
 
 * INTERNALS