Work on new history implementation

history.h

@@ -6,6 +6,137 @@
 #define FISH_HISTORY_H
 
 #include <wchar.h>
+#include "common.h"
+#include "pthread.h"
+#include <vector>
+#include <tr1/memory>
+using std::tr1::shared_ptr;
+
+class history_item_t {
+    friend class history_t;
+
+    private:
+    history_item_t(const wcstring &);
+    history_item_t(const wcstring &, time_t);
+
+	/** The actual contents of the entry */
+	wcstring contents;
+    	
+	/** Original creation time for the entry */
+	time_t timestamp;
+    
+    public:
+    const wcstring &str() const { return contents; }
+    bool empty() const { return contents.empty(); }
+    bool matches_search(const wcstring &val) const { return contents.find(val) != wcstring::npos; }
+};
+
+class history_t {
+private:
+    /** No copying */
+    history_t(const history_t&);
+    history_t &operator=(const history_t&);
+
+    /** Private creator */
+    history_t(const wcstring &pname);
+    
+    /** Destructor */
+    ~history_t();
+
+    /** Lock for thread safety */
+    pthread_mutex_t lock;
+
+	/** The name of this list. Used for picking a suitable filename and for switching modes. */
+	const wcstring name;
+	
+	/** New items. */
+	std::vector<history_item_t> new_items;
+    
+	/** The mmaped region for the history file */
+	const char *mmap_start;
+
+	/** The size of the mmaped region */
+	size_t mmap_length;
+
+	/**
+	   Timestamp of last save
+	*/
+	time_t save_timestamp;
+    
+    static history_item_t decode_item(const char *ptr, size_t len);
+    
+    void populate_from_mmap(void);
+    
+    /** List of old items, as offsets into out mmap data */
+    std::vector<size_t> old_item_offsets;
+    
+    /** Whether we've loaded old items */
+    bool loaded_old;
+    
+    /** Loads old if necessary */
+    void load_old_if_needed(void);
+    
+public:
+    /** Returns history with the given name, creating it if necessary */
+    static history_t & history_with_name(const wcstring &name);
+    
+    /** Add a new history item to the end */
+    void add(const wcstring &str);
+    
+    /** Saves history */
+    void save();
+    
+    /** Return the specified history at the specified index. 0 is the index of the current commandline. */
+    history_item_t item_at_index(size_t idx);
+};
+
+class history_search_t {
+
+    /** The history in which we are searching */
+    history_t * history;
+
+    /** The search term */
+    wcstring term;
+    
+    /** Current index into the history */
+    size_t idx;
+        
+public:
+
+    /** Finds the next search term (forwards in time). Returns true if one was found. */
+    bool go_forwards(void);
+    
+    /** Finds the previous search result (backwards in time). Returns true if one was found. */
+    bool go_backwards(void);
+    
+    /** Goes to the end (forwards) */
+    void go_to_end(void);
+    
+    /** Goes to the beginning (backwards) */
+    void go_to_beginning(void);
+    
+    /** Returns the current search result. asserts if there is no current item. */
+    history_item_t current_item(void) const;
+
+    /** Constructor */
+    history_search_t(history_t &hist, const wcstring &str) :
+        history(&hist),
+        term(str),
+        idx()
+    {
+    }
+    
+    /* Default constructor */
+    history_search_t() :
+        history(),
+        term(),
+        idx()
+    {
+    }
+    
+};
+
+
 
 /**
    Init history library. The history file won't actually be loaded
@@ -14,56 +145,10 @@
 void history_init();
 
 /**
-   Saves the new history to disc and frees all memory used by the history.
+   Saves the new history to disc.
 */
 void history_destroy();
 
-/**
-  Add a new history item to the bottom of the history, containing a
-  copy of str. Remove any duplicates. Moves the current item past the
-  end of the history list.
-*/
-void history_add( const wchar_t *str );
-
-/**
-  Find previous history item starting with str. If this moves before
-  the start of the history, str is returned.
-*/
-const wchar_t *history_prev_match( const wchar_t *str );
-
-/**
-   Return the specified history at the specified index, or 0 if out of bounds. 0 is the index of the current commandline.
-*/
-wchar_t *history_get( int idx );
-
-
-/**
-   Move to first history item
-*/
-void history_first();
-
-/**
-   Make current point to last history item
-*/
-void history_reset();
-
-
-/**
-  Find next history item starting with str. If this moves past
-  the end of the history, str is returned.  
-*/
-const wchar_t *history_next_match( const wchar_t *str);
-
-
-/**
-   Set the current mode name for history. Each application that uses
-   the history has it's own mode. This must be called prior to any use
-   of the history.
-*/
-
-void history_set_mode( const wchar_t *name );
-
-
 /**
    Perform sanity checks
 */