From 448bcba1dc0825d60fc10f838e02687943cd9464 Mon Sep 17 00:00:00 2001
From: Alexander Hoffer <contact@alexanderhoffer.com>
Date: Tue, 21 Jul 2026 16:14:49 +0100
Subject: [PATCH] Fix region command whitespace parsing

---
 src/Utils.cpp                  | 18 ++++++++++++-
 src/Utils.h                    | 10 ++++++++
 src/helpers/CommonCLI.cpp      |  2 +-
 test/test_utils/test_tohex.cpp | 47 ++++++++++++++++++++++++++++++++++
 4 files changed, 75 insertions(+), 2 deletions(-)

diff --git a/src/Utils.cpp b/src/Utils.cpp
index 186c8720a2..1263ce5f44 100644
--- a/src/Utils.cpp
+++ b/src/Utils.cpp
@@ -150,4 +150,20 @@ int Utils::parseTextParts(char* text, const char* parts[], int max_num, char sep
   return num;
 }
 
-}
\ No newline at end of file
+int Utils::parseTextPartsSkippingEmpty(char* text, const char* parts[], int max_num, char separator) {
+  int num = 0;
+  char* sp = text;
+  while (*sp && num < max_num) {
+    while (*sp == separator) sp++;
+    if (*sp == '\0') break;
+
+    parts[num++] = sp;
+    while (*sp && *sp != separator) sp++;
+    if (*sp) {
+      *sp++ = 0;
+    }
+  }
+  return num;
+}
+
+}
diff --git a/src/Utils.h b/src/Utils.h
index 5736b8747a..549269b9a4 100644
--- a/src/Utils.h
+++ b/src/Utils.h
@@ -81,6 +81,16 @@ class Utils {
    */
   static int parseTextParts(char* text, const char* parts[], int max_num, char separator=',');
 
+  /**
+   * \brief  parse 'text' into non-empty parts separated by 'separator' char.
+   * \param  text  the text to parse (note is MODIFIED!)
+   * \param  parts  destination array to store pointers to starts of parse parts
+   * \param  max_num  max elements to store in 'parts' array
+   * \param  separator  the separator character; consecutive instances are treated as one
+   * \returns  the number of non-empty parts parsed (in 'parts')
+   */
+  static int parseTextPartsSkippingEmpty(char* text, const char* parts[], int max_num, char separator=',');
+
   static bool isHexChar(char c);
 };
 
diff --git a/src/helpers/CommonCLI.cpp b/src/helpers/CommonCLI.cpp
index b78ad6ebd6..7faee572a9 100644
--- a/src/helpers/CommonCLI.cpp
+++ b/src/helpers/CommonCLI.cpp
@@ -1002,7 +1002,7 @@ void CommonCLI::handleRegionCmd(char* command, char* reply) {
   }
 
   const char* parts[4];
-  int n = mesh::Utils::parseTextParts(command, parts, 4, ' ');
+  int n = mesh::Utils::parseTextPartsSkippingEmpty(command, parts, 4, ' ');
   if (n == 1) {
     _region_map->exportTo(reply, 160);
   } else if (n >= 2 && strcmp(parts[1], "load") == 0) {
diff --git a/test/test_utils/test_tohex.cpp b/test/test_utils/test_tohex.cpp
index fec3ae4877..37c1e2353d 100644
--- a/test/test_utils/test_tohex.cpp
+++ b/test/test_utils/test_tohex.cpp
@@ -51,6 +51,53 @@ TEST(UtilsToHex, NullTerminatesOnEmptyInput) {
     EXPECT_EQ('\0', output[0]);
 }
 
+TEST(UtilsParseTextParts, PreservesEmptyPartsByDefault) {
+    char input[] = "region default  ";
+    const char* parts[4];
+
+    int count = Utils::parseTextParts(input, parts, 4, ' ');
+
+    ASSERT_EQ(3, count);
+    EXPECT_STREQ("region", parts[0]);
+    EXPECT_STREQ("default", parts[1]);
+    EXPECT_STREQ("", parts[2]);
+}
+
+TEST(UtilsParseTextParts, SkippingEmptyTreatsTrailingSpacesAsNoArgument) {
+    char input[] = "region default  ";
+    const char* parts[4];
+
+    int count = Utils::parseTextPartsSkippingEmpty(input, parts, 4, ' ');
+
+    ASSERT_EQ(2, count);
+    EXPECT_STREQ("region", parts[0]);
+    EXPECT_STREQ("default", parts[1]);
+}
+
+TEST(UtilsParseTextParts, SkippingEmptyKeepsNamedArgumentBetweenRepeatedSpaces) {
+    char input[] = "region  default  au-nsw  ";
+    const char* parts[4];
+
+    int count = Utils::parseTextPartsSkippingEmpty(input, parts, 4, ' ');
+
+    ASSERT_EQ(3, count);
+    EXPECT_STREQ("region", parts[0]);
+    EXPECT_STREQ("default", parts[1]);
+    EXPECT_STREQ("au-nsw", parts[2]);
+}
+
+TEST(UtilsParseTextParts, KeepsExplicitNullRegionArgument) {
+    char input[] = "region  default  <null>  ";
+    const char* parts[4];
+
+    int count = Utils::parseTextPartsSkippingEmpty(input, parts, 4, ' ');
+
+    ASSERT_EQ(3, count);
+    EXPECT_STREQ("region", parts[0]);
+    EXPECT_STREQ("default", parts[1]);
+    EXPECT_STREQ("<null>", parts[2]);
+}
+
 int main(int argc, char **argv) {
     ::testing::InitGoogleTest(&argc, argv);
     return RUN_ALL_TESTS();