commit to some level of style in variable naming

This is an ugly patch, and probably does more than I'd like it to. The
idea is that mkinitcpio adopts some sort of consistent style which I'm
actually happy with. I define 3 kinds of variables:

1) local variables: all lower case, and scoped within functions. Use
freely, as they're well contained.

2) global variables: these are known to mkinitcpio internally, but are
global in scope. They mainly carry runtime configuration and collected
data during the image generation process. These are always lower case,
but carry a leading underscore to denote that they're global.

3) "API" variables: also global in scope, but exist "outside" of
mkinitcpio -- either drawn in from the configuration file, or "exported"
to the install hooks. These are always all upper case. When introducing
new variables, extreme care must be taken to pick names that will not
conflict with the environment inherited by mkinitcpio.

A HACKING file is introduced with a similar description of the above,
and more.

Signed-off-by: Dave Reisner <dreisner@archlinux.org>

1 files changed, 46 insertions, 46 deletions

diff --git a/functions b/functions
index e213580..5a75a79 100644
--- a/functions
+++ b/functions
@@ -139,27 +139,31 @@ parseopts() {
 
 plain() {
     local mesg=$1; shift
-    printf "$BOLD    $mesg$NC\n" "$@" >&1
+    printf "    $_color_bold$mesg$_color_none\n" "$@" >&1
+}
+
+quiet() {
+    (( _optquiet )) || plain "$@"
 }
 
 msg() {
     local mesg=$1; shift
-    printf "$GREEN==>$NC$BOLD $mesg$NC\n" "$@" >&1
+    printf "$_color_green==>$_color_none $_color_bold$mesg$_color_none\n" "$@" >&1
 }
 
 msg2() {
     local mesg=$1; shift
-    printf "$BLUE  ->$NC$BOLD $mesg$NC\n" "$@" >&1
+    printf "  $_color_blue->$_color_none $_color_bold$mesg$_color_none\n" "$@" >&1
 }
 
 warning() {
     local mesg=$1; shift
-    printf "$YELLOW==> WARNING:$NC$BOLD $mesg$NC\n" "$@" >&2
+    printf "$_color_yellow==> WARNING:$_color_none $_color_bold$mesg$_color_none\n" "$@" >&2
 }
 
 error() {
     local mesg=$1; shift
-    printf "$RED==> ERROR:$NC$BOLD $mesg$NC\n" "$@" >&2
+    printf "$_color_red==> ERROR:$_color_none $_color_bold$mesg$_color_none\n" "$@" >&2
     return 1
 }
 
@@ -242,7 +246,7 @@ all_modules() {
         mod=${mod##*/}
         mod="${mod%.ko*}"
         printf '%s\n' "${mod//-/_}"
-    done < <(find "$MODULEDIR" -name '*.ko*' -print0 2>/dev/null | grep -EZz "$@")
+    done < <(find "$_d_kmoduledir" -name '*.ko*' -print0 2>/dev/null | grep -EZz "$@")
 
     (( count ))
 }
@@ -269,8 +273,8 @@ add_checked_modules() {
 
     local mod mods
 
-    if [[ -s $MODULE_FILE ]]; then
-        mapfile -t mods < <(all_modules "$@" | grep -xFf "$MODULE_FILE")
+    if [[ -s $_f_autodetect_cache ]]; then
+        mapfile -t mods < <(all_modules "$@" | grep -xFf "$_f_autodetect_cache")
     else
         mapfile -t mods < <(all_modules "$@")
     fi
@@ -289,8 +293,8 @@ checked_modules() {
     # DEPRECATED: Use add_checked_modules instead
     #
 
-    if [[ -s $MODULE_FILE ]]; then
-        grep -xFf "$MODULE_FILE" <(all_modules "$@")
+    if [[ -s $_f_autodetect_cache ]]; then
+        grep -xFf "$_f_autodetect_cache" <(all_modules "$@")
         return 1
     else
         all_modules "$@"
@@ -313,7 +317,7 @@ add_module() {
     module=${1%.ko*}
 
     # skip expensive stuff if this module has already been added
-    (( ADDED_MODULES["${module//-/_}"] )) && return
+    (( _addedmodules["${module//-/_}"] )) && return
 
     while IFS=':= ' read -r -d '' field value; do
         case "$field" in
@@ -341,9 +345,9 @@ add_module() {
     fi
 
     # aggregate modules and add them all at once to save some forks
-    (( QUIET )) || plain "adding module: %s" "$1"
-    MODPATHS+=("$path")
-    ADDED_MODULES["${module//-/_}"]=1
+    quiet "adding module: %s" "$1"
+    _modpaths+=("$path")
+    _addedmodules["${module//-/_}"]=1
 
     # handle module quirks
     case $module in
@@ -397,7 +401,7 @@ add_dir() {
         return 0
     fi
 
-    (( QUIET )) || plain "adding dir: %s" "$path"
+    quiet "adding dir: %s" "$path"
     command install -dm$mode "$BUILDROOT$path"
 }
 
@@ -407,28 +411,26 @@ add_symlink() {
     #   $1: pathname of symlink on image
     #   $2: absolute path to target of symlink (optional, can be read from $1)
 
-    local name_=$1 target_=$2
+    local name=$1 target=$2
 
     (( $# == 1 || $# == 2 )) || return 1
 
-    if [[ -z $target_ ]]; then
-        target_=$(readlink -f "$name_")
-        if [[ -z $target_ ]]; then
-            error 'invalid symlink: %s' "$name_"
+    if [[ -z $target ]]; then
+        target=$(readlink -f "$name")
+        if [[ -z $target ]]; then
+            error 'invalid symlink: %s' "$name"
             return 1
         fi
     fi
 
-    add_dir "${name_%/*}"
+    add_dir "${name%/*}"
 
-    if (( ! QUIET )); then
-        if [[ -L $BUILDROOT$1 ]]; then
-            plain "overwriting symlink %s -> %s" "$name_" "$target_"
-        else
-            plain "adding symlink: %s -> %s" "$name_" "$target_"
-        fi
+    if [[ -L $BUILDROOT$1 ]]; then
+        quiet "overwriting symlink %s -> %s" "$name" "$target"
+    else
+        quiet "adding symlink: %s -> %s" "$name" "$target"
     fi
-    ln -sfn "$target_" "$BUILDROOT$name_"
+    ln -sfn "$target" "$BUILDROOT$name"
 }
 
 add_file() {
@@ -454,12 +456,10 @@ add_file() {
         return 1
     fi
 
-    if (( ! QUIET )); then
-        if [[ -e $BUILDROOT$dest ]]; then
-            plain "overwriting file: %s" "$dest"
-        else
-            plain "adding file: %s" "$dest"
-        fi
+    if [[ -e $BUILDROOT$dest ]]; then
+        quiet "overwriting file: %s" "$dest"
+    else
+        quiet "adding file: %s" "$dest"
     fi
     command install -Dm$mode "$src" "$BUILDROOT$dest"
 }
@@ -473,7 +473,7 @@ add_runscript() {
 
     local funcs fn script hookname=${SCRIPT:-${BASH_SOURCE[1]##*/}}
 
-    if ! script=$(find_in_dirs "$hookname" "${HOOKDIR[@]}"); then
+    if ! script=$(find_in_dirs "$hookname" "${_d_hooks[@]}"); then
         error "runtime script for \`%s' not found" "$hookname"
         return
     fi
@@ -485,16 +485,16 @@ add_runscript() {
     for fn in "${funcs[@]}"; do
         case $fn in
             run_earlyhook)
-                RUNHOOKS['early']+=" $hookname"
+                _runhooks['early']+=" $hookname"
                 ;;
             run_hook)
-                RUNHOOKS['hooks']+=" $hookname"
+                _runhooks['hooks']+=" $hookname"
                 ;;
             run_latehook)
-                RUNHOOKS['late']+=" $hookname"
+                _runhooks['late']+=" $hookname"
                 ;;
             run_cleanuphook)
-                RUNHOOKS['cleanup']="$hookname ${RUNHOOKS['cleanup']}"
+                _runhooks['cleanup']="$hookname ${_runhooks['cleanup']}"
                 ;;
         esac
     done
@@ -595,22 +595,22 @@ write_image_config() {
     # write the config as runtime config and as a pristine build config
     # (for audting purposes) to the image.
 
-    tee "$BUILDROOT/buildconfig" < "$CONFIG" | {
+    tee "$BUILDROOT/buildconfig" < "$_f_config" | {
         . /dev/stdin
 
         # sanitize of any extra whitespace
         read -ra modules <<<"${MODULES//-/_}"
         for mod in "${modules[@]%\?}"; do
             # only add real modules (2 == builtin)
-            (( ADDED_MODULES["$mod"] == 1 )) && add+=("$mod")
+            (( _addedmodules["$mod"] == 1 )) && add+=("$mod")
         done
         (( ${#add[*]} )) && printf 'MODULES="%s"\n' "${add[*]}"
 
         printf '%s="%s"\n' \
-            'EARLYHOOKS' "${RUNHOOKS['early']# }" \
-            'HOOKS' "${RUNHOOKS['hooks']# }" \
-            'LATEHOOKS' "${RUNHOOKS['late']# }" \
-            'CLEANUPHOOKS' "${RUNHOOKS['cleanup']% }"
+            'EARLYHOOKS' "${_runhooks['early']# }" \
+            'HOOKS' "${_runhooks['hooks']# }" \
+            'LATEHOOKS' "${_runhooks['late']# }" \
+            'CLEANUPHOOKS' "${_runhooks['cleanup']% }"
     } >"$BUILDROOT/config"
 }
 
@@ -653,7 +653,7 @@ run_build_hook() {
     local MODULES= BINARIES= FILES= SCRIPT=
 
     # find script in install dirs
-    if ! script=$(find_in_dirs "$hook" "${INSTDIR[@]}"); then
+    if ! script=$(find_in_dirs "$hook" "${_d_install[@]}"); then
         error "Hook '$hook' cannot be found"
         return 1
     fi