1 files changed, 124 insertions, 0 deletions
diff --git a/scrollback.c b/scrollback.c
new file mode 100644
index 0000000..782afe4
--- /dev/null
+++ b/scrollback.c
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+/* $XTermId: scrollback.c,v 1.15 2011/09/11 14:59:40 tom Exp $ */
+
+/*
+ * Copyright 2009-2010,2011 by Thomas E. Dickey
+ *
+ *                         All Rights Reserved
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name(s) of the above copyright
+ * holders shall not be used in advertising or otherwise to promote the
+ * sale, use or other dealings in this Software without prior written
+ * authorization.
+ */
+
+#include <xterm.h>
+
+#define REAL_ROW(screen, row) ((row) + 1 + (screen)->saved_fifo)
+#define ROW2FIFO(screen, row) \
+	(unsigned) (REAL_ROW(screen, row) % (screen)->savelines)
+
+/*
+ * Given a row-number, find the corresponding data for the line in the VT100
+ * widget's saved-line FIFO.  The row-number (from getLineData) is negative.
+ * So we just count backwards from the last saved line.
+ */
+LineData *
+getScrollback(TScreen * screen, int row)
+{
+    LineData *result = 0;
+
+    if (screen->saved_fifo > 0 && REAL_ROW(screen, row) >= 0) {
+	unsigned which = ROW2FIFO(screen, row);
+	ScrnBuf where = scrnHeadAddr(screen, screen->saveBuf_index, which);
+	result = (LineData *) where;
+    }
+
+    TRACE(("getScrollback %d -> %d -> %p\n",
+	   row, ROW2FIFO(screen, row),
+	   (void *) result));
+    return result;
+}
+
+/*
+ * Allocate a new row in the scrollback FIFO, returning a pointer to it.
+ */
+LineData *
+addScrollback(TScreen * screen)
+{
+    ScrnBuf where = 0;
+    unsigned which;
+    unsigned ncols = (unsigned) MaxCols(screen);
+    Char *block;
+
+    if (screen->saveBuf_index != 0) {
+	screen->saved_fifo++;
+	TRACE(("addScrollback %lu\n", screen->saved_fifo));
+
+	/* first, see which index we'll use */
+	which = (unsigned) (screen->saved_fifo % screen->savelines);
+	where = scrnHeadAddr(screen, screen->saveBuf_index, which);
+
+	/* discard any obsolete index data */
+	if (screen->saved_fifo > screen->savelines) {
+	    LineData *prior = (LineData *) where;
+	    /*
+	     * setupLineData uses the attribs as the first address used from the
+	     * data block.
+	     */
+	    if (prior->attribs != 0) {
+		TRACE(("...freeing prior FIFO data in slot %d: %p->%p\n",
+		       which, (void *) prior, prior->attribs));
+		free(prior->attribs);
+		prior->attribs = 0;
+	    }
+	}
+
+	/* allocate the new data */
+	block = allocScrnData(screen, 1, ncols);
+
+	/* record the new data in the index */
+	setupLineData(screen, where, (Char *) block, 1, ncols);
+
+	TRACE(("...storing new FIFO data in slot %d: %p->%p\n",
+	       which, (void *) where, block));
+
+    }
+    return (LineData *) where;
+}
+
+void
+deleteScrollback(TScreen * screen, int row)
+{
+    unsigned which = ROW2FIFO(screen, row);
+    ScrnBuf where = scrnHeadAddr(screen, screen->saveBuf_index, which);
+    LineData *prior = (LineData *) where;
+    /*
+     * setupLineData uses the attribs as the first address used from the
+     * data block.
+     */
+    if (prior->attribs != 0) {
+	TRACE(("...freeing prior FIFO data in slot %d: %p->%p\n",
+	       which, (void *) prior, prior->attribs));
+	free(prior->attribs);
+	prior->attribs = 0;
+    }
+}