Use the new 'select' option to make the shell config

much less evil and far more obvious.
 -Erik

1 files changed, 27 insertions, 38 deletions

diff --git a/shell/Config.in b/shell/Config.in
index 6103ccfda..bd6f39f7d 100644
--- a/shell/Config.in
+++ b/shell/Config.in
@@ -13,15 +13,19 @@ choice
           and full featured.
 
 config CONFIG_FEATURE_SH_IS_ASH
+        select CONFIG_ASH
         bool "ash"
 
 config CONFIG_FEATURE_SH_IS_HUSH
+        select CONFIG_HUSH
         bool "hush"
 
 config CONFIG_FEATURE_SH_IS_LASH
+        select CONFIG_LASH
         bool "lash"
 
 config CONFIG_FEATURE_SH_IS_MSH
+        select CONFIG_MSH
         bool "msh"
 
 config CONFIG_FEATURE_SH_IS_NONE
@@ -29,20 +33,15 @@ config CONFIG_FEATURE_SH_IS_NONE
 
 endchoice
 
-if CONFIG_FEATURE_SH_IS_ASH
-        config CONFIG_ASH
-        default y
-
-        comment "ash (forced enabled as default shell)"
-endif
-        
-if !CONFIG_FEATURE_SH_IS_ASH
 config CONFIG_ASH
         bool "ash"
         default y
         help
-          Make sh a link to ash.
-endif
+          Tha 'ash' shell adds about 60k in the default configuration and is
+          the most complete and most pedantically correct shell included with
+          busybox.  This shell is actually a derivitive the Debian 'dash' shell
+          (by Herbert Xu), which was created by porting the 'ash' shell
+          (written by Kenneth Almquist) from NetBSD.  
 
 comment "Ash Shell Options"
         depends on CONFIG_ASH
@@ -98,51 +97,41 @@ config CONFIG_ASH_OPTIMIZE_FOR_SIZE
         help
           Compile ash for reduced size at price of speed.
 
-if CONFIG_FEATURE_SH_IS_HUSH
-        config CONFIG_HUSH
-        default y
-
-        comment "hush (forced enabled as default shell)"
-endif
-        
-if !CONFIG_FEATURE_SH_IS_HUSH
 config CONFIG_HUSH
         bool "hush"
         default n
         help
-          Make sh a link to hush.
-endif
+          hush is very small shell (just 18k) and it has fairly complete Bourne
+          shell grammer.  It even handles all the normal flow control options
+          such as if/then/elif/else/fi, for/in/do/done, while loops, etc.
 
-if CONFIG_FEATURE_SH_IS_LASH
-        config CONFIG_LASH
-        default y
+          It does not handle case/esac, select, function, here documents ( <<
+          word ), arithmetic expansion, aliases, brace expansion, tilde
+          expansion, &> and >& redirection of stdout+stderr, etc.
 
-        comment "lash (forced enabled as default shell)"
-endif
 
-if !CONFIG_FEATURE_SH_IS_LASH
 config CONFIG_LASH
         bool "lash"
         default n
         help
-          Make sh a link to lash.
-endif
-
-if CONFIG_FEATURE_SH_IS_MSH
-        config CONFIG_MSH
-        default y
+          lash is the very smallest shell (adds just 10k) and it is quite
+          usable as a command prompt, but it is not suitable for any but the
+          most trivial scripting (such as an initrd that calls insmod a few
+          times) since it does not understand any Bourne shell grammer.  It
+          does handle pipes, redirects, and job control though.  Adding in
+          command editing makes it a very nice lightweight command prompt.
 
-        comment "msh (forced enabled as default shell)"
-endif
 
-if !CONFIG_FEATURE_SH_IS_MSH
 config CONFIG_MSH
         bool "msh"
         default n
         help
-          Make sh a link to msh.
-endif
-
+          The minix shell (adds just 30k) is quite complete and handles things
+          like for/do/done, case/esac and all the things you expect a Bourne
+          shell to do.  It is not always pedantically correct about Bourne
+          shell grammer (try running the shell testscript "tests/sh.testcases"
+          on it and compare vs bash) but for most things it works quite well.
+          It also uses only vfork, so it can be used on uClinux systems.
 
 comment "Bourne Shell Options"
         depends on CONFIG_MSH || CONFIG_LASH || CONFIG_HUSH || CONFIG_ASH