From a4099970069e8517dcad586ca63b370026f9f89e Mon Sep 17 00:00:00 2001
From: Francesco Cozzuto <francesco.cozzuto@gmail.com>
Date: Sat, 6 Dec 2025 01:03:10 +0100
Subject: [PATCH] Add url_decode_field

---
 url.c | 31 +++++++++++++++++++++++++++++++
 url.h |  2 ++
 2 files changed, 33 insertions(+)

diff --git a/url.c b/url.c
index 1307440..98fc93d 100644
--- a/url.c
+++ b/url.c
@@ -901,3 +901,34 @@ int url_remove_white_space(char *src, int len, char *dst, int cap)
 
     return copied;
 }
+
+int url_decode_field(URL_String field, char *dst, int cap)
+{
+    char *src = field.ptr;
+    int   len = field.len;
+    int   rd  = 0;
+    int   wr  = 0;
+
+    while (rd < len) {
+
+        int ret = is_percent_encoded(src, len, rd);
+        if (ret < 0)
+            return -1;
+
+        char c;
+        if (ret == 1) {
+            int h = hex_digit_to_int(src[rd+1]);
+            int l = hex_digit_to_int(src[rd+2]);
+            c = (char) ((h << 4) | l);
+            rd += 3;
+        } else {
+            c = src[rd];
+            rd++;
+        }
+
+        if (wr < cap)
+            dst[wr] = c;
+        wr++;
+    }
+    return wr;
+}
diff --git a/url.h b/url.h
index acaa2be..4021074 100644
--- a/url.h
+++ b/url.h
@@ -110,4 +110,6 @@ int url_resolve_reference(char *src, int len, int *pcur,
 
 int url_remove_white_space(char *src, int len, char *dst, int cap);
 
+int url_decode_field(URL_String field, char *dst, int cap);
+
 #endif // URL_INCLUDED