From 98a78a708a970bcab41ce2e8e8a3e9549d4fcb03 Mon Sep 17 00:00:00 2001
From: 0xFEEDC0DE64 <daniel@brunner.ninja>
Date: Thu, 15 Jul 2021 17:04:27 +0200
Subject: [PATCH] added urldecode()

---
 src/espstrutils.cpp | 34 ++++++++++++++++++++++++++++++++++
 src/espstrutils.h   |  2 ++
 2 files changed, 36 insertions(+)

diff --git a/src/espstrutils.cpp b/src/espstrutils.cpp
index 2980659..95c9cf5 100644
--- a/src/espstrutils.cpp
+++ b/src/espstrutils.cpp
@@ -1,5 +1,8 @@
 #include "espstrutils.h"
 
+// system includes
+#include <cctype>
+
 namespace espcpputils {
 
 std::string toString(sntp_sync_mode_t val)
@@ -13,4 +16,35 @@ std::string toString(sntp_sync_mode_t val)
     return std::string{"Unknown sntp_sync_mode_t("} + std::to_string(int(val)) + ')';
 }
 
+void urldecode(char *dst, const char *src)
+{
+    while (*src) {
+        char a, b;
+        if ((*src == '%') && ((a = src[1]) && (b = src[2])) && (std::isxdigit(a) && std::isxdigit(b))) {
+            if (a >= 'a')
+                a -= 'a'-'A';
+            if (a >= 'A')
+                a -= ('A' - 10);
+            else
+                a -= '0';
+
+            if (b >= 'a')
+                b -= 'a'-'A';
+            if (b >= 'A')
+                b -= ('A' - 10);
+            else
+                b -= '0';
+
+            *dst++ = 16*a+b;
+            src+=3;
+        } else if (*src == '+') {
+            *dst++ = ' ';
+            src++;
+        } else
+            *dst++ = *src++;
+    }
+
+    *dst++ = '\0';
+}
+
 } // namespace espcpputils
diff --git a/src/espstrutils.h b/src/espstrutils.h
index 9c4ca5a..8694162 100644
--- a/src/espstrutils.h
+++ b/src/espstrutils.h
@@ -10,4 +10,6 @@ namespace espcpputils {
 
 std::string toString(sntp_sync_mode_t val);
 
+void urldecode(char *dst, const char *src);
+
 } // namespace espcpputils