[vte] Interpret and document negative number of scrollback lines as infinite

[Behdad Esfahbod <behdad src gnome org>]

commit 592ba42cbfa3e9e948226bcef832e7fd30f5fae7
Author: Behdad Esfahbod <behdad behdad org>
Date:   Fri Oct 23 18:37:42 2009 -0400

    Interpret and document negative number of scrollback lines as infinite

 src/vte.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/src/vte.c b/src/vte.c
index f8eb3ad..5ae939f 100644
--- a/src/vte.c
+++ b/src/vte.c
@@ -12990,7 +12990,11 @@ vte_terminal_get_cursor_shape(VteTerminal *terminal)
  * Sets the length of the scrollback buffer used by the terminal.  The size of
  * the scrollback buffer will be set to the larger of this value and the number
  * of visible rows the widget can display, so 0 can safely be used to disable
- * scrollback.  Note that this setting only affects the normal screen buffer.
+ * scrollback.
+ *
+ * A negative value means "infinite scrollback".
+ *
+ * Note that this setting only affects the normal screen buffer.
  * For terminal types which have an alternate screen buffer, no scrollback is
  * allowed on the alternate screen buffer.
  *
@@ -13005,6 +13009,9 @@ vte_terminal_set_scrollback_lines(VteTerminal *terminal, glong lines)
 
 	g_return_if_fail(VTE_IS_TERMINAL(terminal));
 
+	if (lines < 0)
+		lines = G_MAXLONG;
+
         object = G_OBJECT(terminal);
         pvt = terminal->pvt;