From 2d2d545966d5b5058a6a2dba434cc86679e06765 Mon Sep 17 00:00:00 2001
From: Joursoir <chat@joursoir.net>
Date: Sat, 22 May 2021 21:04:54 +0000
Subject: add sub-module 'url' to decode URL encoding

---
 url.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 url.h |  7 +++++++
 2 files changed, 69 insertions(+)
 create mode 100644 url.c
 create mode 100644 url.h

diff --git a/url.c b/url.c
new file mode 100644
index 0000000..23c0e45
--- /dev/null
+++ b/url.c
@@ -0,0 +1,62 @@
+#include <stddef.h>
+#include <ctype.h>
+
+#include "xstring.h"
+#include "url.h"
+
+static int url_decode_hex_char(const char *query)
+{
+	int out = 0, ch, i;
+	for(i = 0; i < 2; i++) {
+		ch = *query;
+		out <<= 4;
+		if(isdigit(ch))
+			out += ch - '0';
+		else if(isalpha(ch))
+			out += tolower(ch) - 'a' + 10;
+		else
+			return -1;
+		query++;
+	}
+	return out;
+}
+
+static string *url_decode(const char **query, char delimiter)
+{
+	int ch;
+	const char *str = *query;
+	string *dest = string_alloc(NULL, NULL);
+
+	while((ch = *str)) {
+		str++;
+
+		if(ch == delimiter)
+			break;
+
+		if(ch == '%') {
+			ch = url_decode_hex_char(str);
+			if(ch) {
+				string_addch(dest, ch);
+				str += 2;
+			}
+			continue;
+		}
+		
+		if(ch == '+')
+			string_addch(dest, ' ');
+		else
+			string_addch(dest, ch);
+	}
+	*query = str;
+	return dest;
+}
+
+string *url_get_param_name(const char **query)
+{
+	return url_decode(query, '=');
+}
+
+string *url_get_param_value(const char **query)
+{
+	return url_decode(query, '&');
+}
\ No newline at end of file
diff --git a/url.h b/url.h
new file mode 100644
index 0000000..8654094
--- /dev/null
+++ b/url.h
@@ -0,0 +1,7 @@
+#ifndef CTIMELINE_URL_H
+#define CTIMELINE_URL_H
+
+string *url_get_param_name(const char **query);
+string *url_get_param_value(const char **query);
+
+#endif /* CTIMELINE_UI_COMMON_H */
-- 
cgit v1.2.3-18-g5258