parse_dep(): Rewrite parsing code to use sed's ERE

1 files changed, 25 insertions, 45 deletions

diff --git a/lib/deps.sh b/lib/deps.sh
index 27e1b77..c9b065f 100644
--- a/lib/deps.sh
+++ b/lib/deps.sh
@@ -34,10 +34,9 @@ ob_parse_dep()
 	local host_arch=
 	local host_plat=
 	local dep=
-	local pkgarchqual=
+	local dep_re=
 	local pkg=
 	local archqual=
-	local relver=
 	local rel=
 	local ver=
 	local arches=
@@ -97,54 +96,35 @@ ob_parse_dep()
 	shift $(($OPTIND - 1))
 
 	if [ ${#} -eq 1 ]; then
-		dep="$(printf '%s\n' "${1}" | sed -n '
-			H;                        # Store each input line in the hold space.
-			${
-			  g;                      # Restore everything to the pattern space.
-			  s/[\t\n]/ /g;           # Replace tabs and newlines with spaces.
-			  s/ *\([(\[<]\) */ \1/g; # One space before "(", "[", and "<".
-			  s/ *\([)\]>]\) */\1 /g; # One space after "(", "[", and "<".
-			  s/ *\(<[<=]\) */\1 /g;  # One space after "<<" and "<=".
-			  s/ *\(>[>=]\) */\1 /g;  # One space after ">>" and ">=".
-			  s/ *\(=\) */\1 /g;      # One space after "=".
-			  s/^ *//;                # Remove leading spaces.
-			  s/ *$//;                # Remove trailing spaces.
-			  s/  */ /g;              # Remove duplicate spaces.
-			  p;                      # Print the pattern space.
-			};
-			')"
+		dep="${1}"
 	else
 		return 125
 	fi
 
 	# pkg[:archqual] [(rel ver)] [\[arches\]] [<plats>]
-
-	pkgarchqual="${dep%% *}"
-	dep=" ${dep#* }"
-	pkg="${pkgarchqual%:*}"
-	if [ "${pkg}" != "${pkgarchqual}" ]; then
-		archqual="${pkgarchqual##*:}"
-	fi
-
-	if [ "${dep# (*)}" != "${dep}" ]; then
-		relver="${dep# (}"
-		relver="${relver%%)*}"
-		dep="${dep# (*)}"
-		rel="${relver% *}"
-		ver="${relver##* }"
-	fi
-
-	if [ "${dep# \[*\]}" != "${dep}" ]; then
-		arches="${dep# \[}"
-		arches="${arches%%\]*}"
-		dep="${dep# \[*\]}"
-	fi
-
-	if [ "${dep# <*>}" != "${dep}" ]; then
-		plats="${dep# <}"
-		plats="${plats%%>*}"
-		dep="${dep# <*>}"
-	fi
+	dep_re='s/^ *([^ \(\[<]+) *(\((<<|<=|=|>=|>>) *(.+)\))?'
+	dep_re="${dep_re}"' *(\[(.+)\])? *(<(.+)>)? *$/\1\n\3\n\4\n\6\n\8/;'
+
+	# BusyBox sed supports -r and (as of version 1.22.0) -E.
+	dep="$(printf '%s\n' "${dep}" | sed -nr '
+		H;
+		${
+			g;
+			s/[\t\n]/ /g;
+			'"${dep_re}"'
+			p;
+		};
+		')"
+
+	{
+		IFS=':' read pkg archqual
+		read rel
+		read ver
+		read arches
+		read plats
+	} <<-EOF
+		${dep}
+		EOF
 
 	# Set the specified variables.
 	for comp in pkg archqual rel ver arches plats; do