[PATCH setup 1/3] Fix the reading and writing of the "extrakeys" user setting

[Ken Brown <kbrown@cornell.edu>]

ExtraKeysSetting::keybuffer is terminated by LF rather than NUL.  So
we have to replace NUL by LF after calling
UserSettings::get("extrakeys") in the ExtraKeysSetting constructor.
Otherwise the last saved key is discarded.  Also, bufsize has to be
set appropriately before the call to count_keys(), or else all saved
keys are discarded.

Similarly, the final LF in keybuffer has to be replaced by NUL in the
ExtraKeysSetting destructor before the call to
UserSettings::set("extrakeys", keybuffer).  Otherwise we get garbage
at the end of the "extrakeys" setting in setup.rc.
---
 KeysSetting.cc | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/KeysSetting.cc b/KeysSetting.cc
index a21c3c4..ec8e4f9 100644
--- a/KeysSetting.cc
+++ b/KeysSetting.cc
@@ -36,7 +36,10 @@ ExtraKeysSetting::ExtraKeysSetting ():
   const char *p = UserSettings::instance().get ("extrakeys");
   if (p)
     {
+      bufsize = strlen (p) + 1;	// Include final NUL.
       keybuffer = strdup (p);
+      // Replace final NUL by LF.
+      keybuffer[bufsize - 1] = 0x0a;
       // Calling count_keys gets the count but also sizes the buffer
       // correctly, discarding any trailing non-LF-terminated data.
       bufsize = count_keys ();
@@ -46,7 +49,11 @@ ExtraKeysSetting::ExtraKeysSetting ():
 ExtraKeysSetting::~ExtraKeysSetting ()
 {
   if (keybuffer)
-    UserSettings::instance().set ("extrakeys", keybuffer);
+    {
+      // Replace final LF by NUL.
+      keybuffer[bufsize - 1] = '\0';
+      UserSettings::instance().set ("extrakeys", keybuffer);
+    }
 }
 
 void
-- 
2.15.0