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Diffstat (limited to 'contrib/syslinux-4.02/gpxe/src/hci/editstring.c')
-rw-r--r--contrib/syslinux-4.02/gpxe/src/hci/editstring.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/hci/editstring.c b/contrib/syslinux-4.02/gpxe/src/hci/editstring.c
new file mode 100644
index 0000000..648f338
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/hci/editstring.c
@@ -0,0 +1,192 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <assert.h>
+#include <string.h>
+#include <gpxe/keys.h>
+#include <gpxe/editstring.h>
+
+/** @file
+ *
+ * Editable strings
+ *
+ */
+
+static void insert_delete ( struct edit_string *string, size_t delete_len,
+ const char *insert_text )
+ __attribute__ (( nonnull (1) ));
+static void insert_character ( struct edit_string *string,
+ unsigned int character ) __nonnull;
+static void delete_character ( struct edit_string *string ) __nonnull;
+static void backspace ( struct edit_string *string ) __nonnull;
+static void kill_eol ( struct edit_string *string ) __nonnull;
+
+/**
+ * Insert and/or delete text within an editable string
+ *
+ * @v string Editable string
+ * @v delete_len Length of text to delete from current cursor position
+ * @v insert_text Text to insert at current cursor position, or NULL
+ */
+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, new_len;
+
+ /* Calculate lengths */
+ old_len = strlen ( string->buf );
+ assert ( string->cursor <= old_len );
+ max_delete_len = ( old_len - string->cursor );
+ if ( delete_len > max_delete_len )
+ delete_len = max_delete_len;
+ insert_len = ( insert_text ? strlen ( insert_text ) : 0 );
+ 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 ),
+ ( string->buf + string->cursor + delete_len ),
+ ( max_delete_len + 1 - delete_len ) );
+
+ /* Copy inserted text to cursor position */
+ memcpy ( ( string->buf + string->cursor ), insert_text, insert_len );
+ string->cursor += insert_len;
+}
+
+/**
+ * Insert character at current cursor position
+ *
+ * @v string Editable string
+ * @v character Character to insert
+ */
+static void insert_character ( struct edit_string *string,
+ unsigned int character ) {
+ char insert_text[2] = { character, '\0' };
+ insert_delete ( string, 0, insert_text );
+}
+
+/**
+ * Delete character at current cursor position
+ *
+ * @v string Editable string
+ */
+static void delete_character ( struct edit_string *string ) {
+ insert_delete ( string, 1, NULL );
+}
+
+/**
+ * Delete character to left of current cursor position
+ *
+ * @v string Editable string
+ */
+static void backspace ( struct edit_string *string ) {
+ if ( string->cursor > 0 ) {
+ string->cursor--;
+ delete_character ( string );
+ }
+}
+
+/**
+ * Delete to end of line
+ *
+ * @v string Editable string
+ */
+static void kill_eol ( struct edit_string *string ) {
+ insert_delete ( string, ~( ( size_t ) 0 ), NULL );
+}
+
+/**
+ * Edit editable string
+ *
+ * @v string Editable string
+ * @v key Key pressed by user
+ * @ret key Key returned to application, or zero
+ *
+ * Handles keypresses and updates the content of the editable string.
+ * Basic line editing facilities (delete/insert/cursor) are supported.
+ * If edit_string() understands and uses the keypress it will return
+ * 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;
+ size_t len = strlen ( string->buf );
+
+ /* 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 );
+ } else switch ( key ) {
+ case KEY_BACKSPACE:
+ /* Backspace */
+ backspace ( string );
+ break;
+ case KEY_DC:
+ case CTRL_D:
+ /* Delete character */
+ delete_character ( string );
+ break;
+ case CTRL_K:
+ /* Delete to end of line */
+ kill_eol ( string );
+ break;
+ case KEY_HOME:
+ case CTRL_A:
+ /* Start of line */
+ string->cursor = 0;
+ break;
+ case KEY_END:
+ case CTRL_E:
+ /* End of line */
+ string->cursor = len;
+ break;
+ case KEY_LEFT:
+ case CTRL_B:
+ /* Cursor left */
+ if ( string->cursor > 0 )
+ string->cursor--;
+ break;
+ case KEY_RIGHT:
+ case CTRL_F:
+ /* Cursor right */
+ if ( string->cursor < len )
+ string->cursor++;
+ break;
+ default:
+ retval = key;
+ break;
+ }
+
+ return retval;
+}