From 1a9d4e86538b2c8dbd8ad11c4333f0db64febd50 Mon Sep 17 00:00:00 2001
From: John Ericson <address@hidden>
Date: Sat, 21 Apr 2018 22:58:24 -0400
Subject: [PATCH 2/3] Rewrite logic handling n `-`-separated components

The old logic was a bit hard to follow due to lots of sed and
unintuitive collapsing of cases. The code now works like this

 - 4 components is always parsed as
   CPU_TYPE-MANUFACTURER-KERNEL-OPERATING_SYSTEM

 - 2 components is always parsed as
   CPU_TYPE-OPERATING_SYSTEM

 - 1 component is always parsed as
   CPU_TYPE

 - 3 components is ambiguous and parsed as either
   CPU_TYPE-MANUFACTURER-OPERATING_SYSTEM
   CPU_TYPE-KERNEL-OPERATING_SYSTEM

The old code differed semantically in that

 - The 4-case was awkwardly folded into the 3-case disambiguation

 - The "android-linux" ad-hoc fixdup did something different in the
   non-3 cases, but isn't intended to apply in those cases.
---
 config.sub | 60 ++++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 38 insertions(+), 22 deletions(-)

diff --git a/config.sub b/config.sub
index 721d1dc..24ffe7c 100755
--- a/config.sub
+++ b/config.sub
@@ -110,33 +110,49 @@ case $# in
     exit 1;;
 esac
 
-# Separate what the user gave into CPU-COMPANY and OS or KERNEL-OS (if any).
-# Here we must recognize all the valid KERNEL-OS combinations.
-maybe_os=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\2/'`
-case $maybe_os in
-  nto-qnx* | linux-gnu* | linux-android* | linux-dietlibc | linux-newlib* | \
-  linux-musl* | linux-uclibc* | uclinux-uclibc* | uclinux-gnu* | kfreebsd*-gnu* | \
-  knetbsd*-gnu* | netbsd*-gnu* | netbsd*-eabi* | \
-  kopensolaris*-gnu* | cloudabi*-eabi* | \
-  storm-chaos* | os2-emx* | rtmk-nova*)
-    os=-$maybe_os
-    basic_machine=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`
-    ;;
-  android-linux)
-    os=-linux-android
-    basic_machine=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`-unknown
+c1=`echo "$1" | sed 's/^\([^-]*\).*$/\1/'`
+c2=`echo "$1" | sed 's/^[^-]*-\([^-]*\).*$/\1/'`
+c3=`echo "$1" | sed 's/^[^-]*-[^-]*-\([^-]*\).*$/\1/'`
+c4=`echo "$1" | sed 's/^[^-]*-[^-]*-[^-]*-\([^-]*\).*$/\1/'`
+
+# Fix android-linux to be linux-android KERNEL-OS with unknown COMPANY
+if [ "$c2-$c3" = "android-linux" ]; then
+  c2=unknown
+  c3=linux
+  c4=android
+  set $c1-$c2-$c3-$c4
+fi
+
+case $1 in
+  *-*-*-*)
+    basic_machine=$c1-$c2
+    os=-$c3-$c4
     ;;
-  *)
-    basic_machine=`echo "$1" | sed 's/-[^-]*$//'`
-    case $1 in
-      *-*)
-        os=`echo "$1" | sed 's/.*-/-/'`
+  *-*-*)
+    # Ambiguous whether COMPANY is present, or skipped and KERNEL-OS is two parts
+    maybe_os=$c2-$c3
+    case $maybe_os in
+      nto-qnx* | linux-gnu* | linux-android* | linux-dietlibc | linux-newlib* | \
+      linux-musl* | linux-uclibc* | uclinux-uclibc* | uclinux-gnu* | kfreebsd*-gnu* | \
+      knetbsd*-gnu* | netbsd*-gnu* | netbsd*-eabi* | \
+      kopensolaris*-gnu* | cloudabi*-eabi* | \
+      storm-chaos* | os2-emx* | rtmk-nova*)
+        basic_machine=$c1
+        os=-$maybe_os
         ;;
       *)
-        os=
-        ;;
+        basic_machine=$c1-$c2
+        os=-$c3
     esac
     ;;
+  *-*)
+    basic_machine=$c1
+    os=-$c2
+    ;;
+  *)
+    basic_machine=$1
+    os=
+    ;;
 esac
 
 ### Let's recognize common machines as not being operating systems so
-- 
2.16.2