Improve coding style

Use CamelCase for inheritable variable names, avoid re-hashing each
module twice and add function and variable docstrings, remove unnecessary
whitespace

src/bin/sfembed

@@ -24,7 +24,7 @@ chk_applicable() {
 }
 
 mkbody() {
-    debug -v to_embed
+    debug -v ScriptFullPath
     mkhead      || return $?
     mkmodules   || return $?
     mkpayload   || return $?
@@ -35,21 +35,23 @@ mkmodules() {
     #
     # Print each module body w/ header
     #
-    local modlist="__shellfu_embed__modlist"
-    local module=""
+    local modlist=__shellfu_embed__modlist
+    local Module
+    local ModuleHash
     (
-        SHELLFU_EMBEDTMP="$modlist" "$to_embed" >&2
+        SHELLFU_EMBEDTMP="$modlist" "$ScriptFullPath" >&2
     )
     awk '!x[$0]++' "$modlist" \
-      | while read -r module;
+      | while read -r Module;
         do
-            think "appending: $module"
-            mkmodule "$module"
+            ModuleHash=$(md5sum "$Module")
+            think "appending: $Module"
+            mkmodule "$Module"
         done
 }
 
 mkpayload() {
-    cat "$to_embed"
+    cat "$ScriptFullPath"
 }
 
 mkfoot() {
@@ -63,21 +65,24 @@ mkmodule() {
     # Print single module body
     #
     echo "#"
-    echo "# begin module: $(md5sum "$module")"
+    echo "# begin module: $ModuleHash"
     echo "#"
     echo
-    cat "$module"
+    cat "$Module"
     echo
     echo "#"
-    echo "# end module: $(md5sum "$module")"
+    echo "# end module: $ModuleHash"
     echo "#"
     echo
 }
 
 mkhead() {
+    #
+    # Print header of the final script
+    #
     echo "#!/bin/bash"
     echo "#"
-    echo "# shellfu embedded: $to_embed"
+    echo "# shellfu embedded: $ScriptFullPath"
     echo "# shellfu version: $SHELLFU_VERSION"
     echo "#"
     echo
@@ -91,9 +96,11 @@ mkhead() {
 }
 
 do_embed() {
-    local tmp="$(mktemp -d -t shellfu_embed.XXXXXXXX)"
-    local es=0
-    local to_embed="$(readlink -f "$script")"
+    local tmp               # temporary dir to run in
+    local es=0              # exit status of this function
+    local ScriptFullPath    # full path to script to embed in
+    tmp=$(mktemp -d -t shellfu_embed.XXXXXXXX)
+    ScriptFullPath=$(readlink -f "$Script")
     pushd "$tmp" >/dev/null
         mkbody; es=$?
     popd >/dev/null
@@ -102,26 +109,20 @@ do_embed() {
 }
 
 main() {
-
-    local script=""     # script to embed libraries into
-
+    local Script        # script to embed libraries into
     while true; do case "$1" in
         -d) PRETTY_DEBUG=true; shift ;;
         -v) PRETTY_VERBOSE=true; shift ;;
         -*) usage ;;
         *)  break ;;
     esac done
-    script="$1"
-
-    test -n "$script" || usage
-    test -f "$script" || die "no such file: $script"
-    test -r "$script" || die "cannot read: $script"
-    chk_applicable "$script" || die "not applicable for embedding: $script"
-
-    debug -v script
-
+    Script="$1"
+    test -n "$Script" || usage
+    test -f "$Script" || die "no such file: $Script"
+    test -r "$Script" || die "cannot read: $Script"
+    chk_applicable "$Script" || die "not applicable for embedding: $Script"
+    debug -v Script
     do_embed
-
 }
 
 main "$@"