[PATCH] Add $pager_min_index_lines config option.

[Piotr Durlej]

Hi everyone,

as a matter of exercise, I've implemented a new mutt option (see the 
description in init.h for the details).

If you like it, please feel free to merge.

Kind regards,
Piotr Durlej

---
 globals.h |  1 +
 init.h    | 14 ++++++++++++++
 pager.c   | 10 ++++++++--
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/globals.h b/globals.h
index fd63bd43..e20c4739 100644
--- a/globals.h
+++ b/globals.h
@@ -236,6 +236,7 @@ WHERE short HistSize;
 WHERE short MenuContext;
 WHERE short PagerContext;
 WHERE short PagerIndexLines;
+WHERE short PagerMinIndexLines;
 WHERE short PagerSkipQuotedContext;
 WHERE short ReadInc;
 WHERE short ReflowWrap;
diff --git a/init.h b/init.h
index dcb664f8..0d3fe87c 100644
--- a/init.h
+++ b/init.h
@@ -2440,6 +2440,20 @@ struct option_t MuttVars[] = {
   ** is less than $$pager_index_lines, then the index will only use as
   ** many lines as it needs.
   */
+  { "pager_min_index_lines", DT_NUM, R_PAGER, {.p=&PagerMinIndexLines}, {.l=0} 
},
+  /*
+  ** .pp
+  ** Controls the \fIminimum\fP number of lines of the mini-index.
+  ** .pp
+  ** If the number of messages in the current folder is less than
+  ** $$pager_min_index_lines, then the index will be padded with empty lines,
+  ** allowing for a mini-index of a constant height.
+  ** This option is otherwise same as the $$pager_index_lines option.
+  ** .pp
+  ** When both $pager_min_index_lines and $pager_index_lines are set, the
+  ** $pager_min_index_lines option determines the minimum number of rows, and
+  ** the $pager_index_lines controls the maximum.
+  */
   { "pager_skip_quoted_context", DT_NUM, R_NONE, {.p=&PagerSkipQuotedContext}, 
{.l=0} },
   /*
   ** .pp
diff --git a/pager.c b/pager.c
index 8df571ab..40b49425 100644
--- a/pager.c
+++ b/pager.c
@@ -1819,11 +1819,14 @@ static void pager_menu_redraw (MUTTMENU *pager_menu)
     memcpy (rd->pager_status_window, MuttStatusWindow, sizeof(mutt_window_t));
     rd->index_status_window->rows = rd->index_window->rows = 0;
 
-    if (IsHeader (rd->extra) && PagerIndexLines)
+    if (IsHeader (rd->extra) && (PagerIndexLines || PagerMinIndexLines))
     {
       memcpy (rd->index_window, MuttIndexWindow, sizeof(mutt_window_t));
       rd->index_window->rows = rd->indexlen > 0 ? rd->indexlen - 1 : 0;
 
+      if (PagerMinIndexLines && rd->index_window->rows <= PagerMinIndexLines)
+        rd->index_window->rows = PagerMinIndexLines - 1;
+
       if (option (OPTSTATUSONTOP))
       {
         memcpy (rd->index_status_window, MuttStatusWindow, 
sizeof(mutt_window_t));
@@ -1879,7 +1882,7 @@ static void pager_menu_redraw (MUTTMENU *pager_menu)
     }
 #endif
 
-    if (IsHeader (rd->extra) && PagerIndexLines)
+    if (IsHeader (rd->extra) && (PagerIndexLines || PagerMinIndexLines))
     {
       if (rd->index == NULL)
       {
@@ -1905,6 +1908,9 @@ static void pager_menu_redraw (MUTTMENU *pager_menu)
       else
         rd->index->top = rd->index->current - rd->indicator;
 
+      if (rd->index->top < 0)
+        rd->index->top = 0;
+
       menu_redraw_index(rd->index);
     }
 
-- 
2.44.0