Provide an edit history to allow caller to efficiently update display.

diff --git a/src/hci/editstring.c b/src/hci/editstring.c
index a17b57619ae1abcf445d29dc39413c685245dacc..f6a11617d684f2a7fa7a52b359b9022441e620bd 100644 (file)
--- a/src/hci/editstring.c
+++ b/src/hci/editstring.c
@@ -35,7 +35,7 @@
  */
 static void insert_delete ( struct edit_string *string, size_t delete_len,
                            const char *insert_text ) {
-       size_t old_len, max_delete_len, insert_len, max_insert_len;
+       size_t old_len, max_delete_len, insert_len, max_insert_len, new_len;
 
        /* Calculate lengths */
        old_len = strlen ( string->buf );
@@ -47,6 +47,11 @@ static void insert_delete ( struct edit_string *string, size_t delete_len,
        max_insert_len = ( ( string->len - 1 ) - ( old_len - delete_len ) );
        if ( insert_len > max_insert_len )
                insert_len = max_insert_len;
+       new_len = ( old_len - delete_len + insert_len );
+
+       /* Fill in edit history */
+       string->mod_start = string->cursor;
+       string->mod_end = ( ( new_len > old_len ) ? new_len : old_len );
 
        /* Move data following the cursor */
        memmove ( ( string->buf + string->cursor + insert_len ),
@@ -113,10 +118,19 @@ static void kill_eol ( struct edit_string *string ) {
  * zero, otherwise it will return the original key.
  *
  * This function does not update the display in any way.
+ *
+ * The string's edit history will be updated to allow the caller to
+ * efficiently bring the display into sync with the string content.
  */
 int edit_string ( struct edit_string *string, int key ) {
        int retval = 0;
 
+       /* Prepare edit history */
+       string->last_cursor = string->cursor;
+       string->mod_start = string->cursor;
+       string->mod_end = string->cursor;
+
+       /* Interpret key */
        if ( ( key >= 0x20 ) && ( key <= 0x7e ) ) {
                /* Printable character; insert at current position */
                insert_character ( string, key );

diff --git a/src/include/gpxe/editstring.h b/src/include/gpxe/editstring.h
index 7dc96d9aaeba71c2a091b4c048b724f7da9b5257..7f3c5dcb142512826f869f022dea743ce545ed88 100644 (file)
--- a/src/include/gpxe/editstring.h
+++ b/src/include/gpxe/editstring.h
@@ -1,5 +1,5 @@
-#ifndef _EDITSTRING_H
-#define _EDITSTRING_H
+#ifndef _GPXE_EDITSTRING_H
+#define _GPXE_EDITSTRING_H
 
 /** @file
  *
@@ -15,8 +15,17 @@ struct edit_string {
        size_t len;
        /** Cursor position */
        unsigned int cursor;
+
+       /* The following items are the edit history */
+
+       /** Last cursor position */
+       unsigned int last_cursor;
+       /** Start of modified portion of string */
+       unsigned int mod_start;
+       /** End of modified portion of string */
+       unsigned int mod_end;
 };
 
 extern int edit_string ( struct edit_string *string, int key );
 
-#endif /* _EDITSTRING_H */
+#endif /* _GPXE_EDITSTRING_H */