From 0e35d77b9cb1376c8310923db69dc2bc7fbe0715 Mon Sep 17 00:00:00 2001
From: Simon Schmid <mail@sschmid.com>
Date: Mon, 28 Oct 2024 21:49:56 +0100
Subject: [PATCH] Fix character classes for BusyBox tr to avoid using sed

---
 src/pw       |  8 ++++++--
 test/pw.bats | 16 ++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/pw b/src/pw
index 28c607d..11c944f 100755
--- a/src/pw
+++ b/src/pw
@@ -187,9 +187,13 @@ pw::output() {
 pw::gen() {
   local -i length=${1:-${PW_GEN_LENGTH}}
   local password="" class="${2:-"${PW_GEN_CLASS}"}"
+
+  # Fix character classes for BusyBox tr
+  [[ "${class}" == "[:graph:]" ]] && class="[:alnum:][:punct:]"
+  [[ "${class}" == "[:print:]" ]] && class="[:alnum:][:punct:][:space:]"
+
   while (( "${#password}" != length )); do
-    # alpine tr does not support [:graph:], use sed instead
-    password+=$(dd if=/dev/urandom bs=$(( length / 64 + 1 )) count=1 2>/dev/null | LC_CTYPE=C LC_ALL=C tr -d '\0[:space:]' | LC_CTYPE=C LC_ALL=C sed "s/[^${class}]//g" | head -c $(( length - ${#password} )))
+    password+=$(dd if=/dev/urandom bs=$(( length / 64 + 1 )) count=1 2>/dev/null | LC_CTYPE=C LC_ALL=C tr -dc "${class}" | head -c $(( length - ${#password} )))
   done
   pw::output "${password}"
 }
diff --git a/test/pw.bats b/test/pw.bats
index 9b0e0cd..70b33a3 100644
--- a/test/pw.bats
+++ b/test/pw.bats
@@ -78,3 +78,19 @@ assert_pw_home() {
   assert_success
   assert_output "22222222"
 }
+
+# @test "BusyBox: replaces [:graph:] with [:alnum:][:punct:]" {
+#   export PW_GEN_LENGTH=64
+#   export PW_GEN_CLASS="[:graph:]"
+#   run pw -p gen
+#   assert_success
+#   assert_output "check manually"
+# }
+
+# @test "alpine: replaces [:print:] with [:alnum:][:punct:][:space:]" {
+#   export PW_GEN_LENGTH=64
+#   export PW_GEN_CLASS="[:print:]"
+#   run pw -p gen
+#   assert_success
+#   assert_output "check manually"
+# }