POSIXify ./configure, and comment some parts of it.

Thanks to Martin GUY for pointing out that ./configure was not POSIXly correct.

 /trunk/configure |   51    35    16     0 +++++++++++++++++++++++++++++++++++----------------
 1 file changed, 35 insertions(+), 16 deletions(-)

1 files changed, 35 insertions, 16 deletions

diff --git a/configure b/configure
index ad61765..a1175b5 100755
--- a/configure
+++ b/configure
@@ -11,9 +11,13 @@ DOCDIR_set=
 MANDIR_set=
 LOCAL_set=
 
-qo_quit=
+do_quit=
 CONTRIB_list=
 
+# Given an option string and the following argument,
+# echoes the value of the option.
+# If --var=val => echoes val and returns 0, meaning second arg was not consumed
+# If --var val => echoes val and returns non null, meaning second arg was used
 get_optval(){
     local ret
     case "$1" in
@@ -29,46 +33,55 @@ get_optval(){
     return ${ret}
 }
 
+# The set_xxx functions will set the corresponding configuration variable
+# They return 0 if second arg was not consumed, and non-zero if it was consumed.
 set_prefix() {
     PREFIX=$(get_optval "$1" "$2")
     return $?
 }
-
 set_bindir() {
     BINDIR_set=1
     BINDIR=$(get_optval "$1" "$2")
     return $?
 }
-
 set_libdir() {
     LIBDIR_set=1
     LIBDIR=$(get_optval "$1" "$2")
     return $?
 }
-
 set_docdir() {
     DOCDIR_set=1
     DOCDIR=$(get_optval "$1" "$2")
     return $?
 }
-
 set_mandir() {
     MANDIR_set=1
     MANDIR=$(get_optval "$1" "$2")
     return $?
 }
 
+# The set_contrib function is different in that it will work like the others,
+# except in two cases:
+# If all => replaces all with the list of all available contribs
+# If list => just echoes the list of all available contribs, and instructs
+# caller to quit immediately by setting do_quit to non null.
+# (can't use the return code, see above).
 set_contrib() {
     opt_val=$(get_optval "$1" "$2")
     local ret=$?
     case "${opt_val}" in
         all)
-            CONTRIB_list=$(LC_ALL=C ls -1 contrib/*.patch.lzma |sed -r -e 's|.*/||; s|\.patch\.lzma||;')
+            CONTRIB_list=$(LC_ALL=C ls -1 contrib/*.patch.lzma  \
+                           |xargs -I {} basename {} .patch.lzma \
+                           |sed -r -e ':a; /$/N; s/\n/,/; ta;'
+                          )
             ;;
         list)
             do_quit=1
             echo "Available contributions:"
-            LC_ALL=C ls -1 contrib/*.patch.lzma |sed -r -e 's|.*/||; s|\.patch\.lzma||; s|^|  |;'
+            LC_ALL=C ls -1 contrib/*.patch.lzma     \
+            |xargs -I {} basename {} .patch.lzma    \
+            |sed -r -e 's/^/  /;'
             ;;
         *)  CONTRIB_list="${CONTRIB_list},${opt_val}";;
     esac
@@ -136,7 +149,10 @@ while [ $# -ne 0 ]; do
     esac
 done
 
+# Use defaults
 [ -z "${PREFIX}" ] && set_prefix "" "${PREFIX_DEFAULT}"
+
+# Special case when installing locally
 if [ "${LOCAL_set}" = "1" ]; then
     set_prefix "" $(pwd)
     set_bindir "" $(pwd)
@@ -150,7 +166,7 @@ fi
 
 # If this version is a svn snapshot, try to get the revision number
 # If we can't get the revision number, use date
-echo -n "Computing version string... "
+printf "Computing version string... "
 case "${VERSION}" in
   *+svn)
     REVISION=$(LC_ALL=C svnversion)
@@ -163,7 +179,9 @@ case "${VERSION}" in
         VERSION="${VERSION}${URL#${ROOT}}@${REVISION}"
         ;;
     esac
-    VERSION="${VERSION/\//_}"
+    # Arrange to have no / in the directory name, no need to create an
+    # arbitrarily deep directory structure
+    VERSION=$(echo "${VERSION}" |sed -r -e 's|/+|_|g;')
     ;;
 esac
 echo "${VERSION}"
@@ -175,16 +193,18 @@ echo "${VERSION}"
 [ -z "${MANDIR_set}" ] && MANDIR="${PREFIX}/share/man/man1"
 
 # Check bash is present, and at least version 3.0
-echo -n "Checking bash is at least bash-3.0... "
+printf "Checking bash is at least bash-3.0... "
 [ -x /bin/bash ] || do_error "bash 3.0 or above was not found in /bin/bash"
 bash_version=$(/bin/bash -c 'echo ${BASH_VERSION}')
 bash_major=$(/bin/bash -c 'echo ${BASH_VERSINFO[0]}')
 [ ${bash_major} -ge 3 ] || do_error "bash 3.0 or above is needed (/bin/bash is ${bash_version})"
 echo "ok (${bash_version})"
 
-echo -n "Applying contributed code: "
-for c in ${CONTRIB_list//,/ }; do
-    echo -n "${c}... "
+printf "Applying contributed code: "
+# It's safer to change all ',' to spaces rather than setting IFS
+CONTRIB_list=$(echo "${CONTRIB_list}" |sed -r -e 's/,+/ /g;')
+for c in ${CONTRIB_list}; do
+    printf "${c}, "
     if [ ! -f "contrib/${c}.patch.lzma" ]; then
         do_error "Contribution '${c}' does not exist"
     fi
@@ -192,7 +212,7 @@ for c in ${CONTRIB_list//,/ }; do
 done
 echo "done"
 
-echo -n "Building up Makefile... "
+printf "Building up Makefile... "
 sed -r -e "s,@@BINDIR@@,${BINDIR},g;"   \
        -e "s,@@LIBDIR@@,${LIBDIR},g;"   \
        -e "s,@@DOCDIR@@,${DOCDIR},g;"   \
@@ -210,6 +230,5 @@ crosstool-NG configured as follows:
   LIBDIR='${LIBDIR}'
   DOCDIR='${DOCDIR}'
   MANDIR='${MANDIR}'
-  CONTRIB='${CONTRIB_list//
-/,}'
+  CONTRIB='${CONTRIB_list}'
 __EOF__