From 795b0ca8d46c9a697fac1eec472a091a55f5676e Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Mon, 19 Jun 2023 01:05:32 +0200
Subject: [PATCH] libc/scanf: Some refactoring

---
 libc/src/scanf.cpp | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/libc/src/scanf.cpp b/libc/src/scanf.cpp
index 472b99b5..acb9d7a5 100644
--- a/libc/src/scanf.cpp
+++ b/libc/src/scanf.cpp
@@ -108,6 +108,13 @@ static void write_parsed_unsigned_integer(size_t value, int flags, va_list ap)
         *va_arg(ap, unsigned int*) = (unsigned int)value;
 }
 
+#define WHITESPACE_CHARACTERS " \t\f\r\n\v"
+
+static void skip_whitespace(const char** str)
+{
+    *str += strspn(*str, WHITESPACE_CHARACTERS);
+}
+
 extern "C"
 {
     int vsscanf(const char* str, const char* format, va_list ap)
@@ -131,8 +138,8 @@ extern "C"
                     continue;
                 }
 
-                format += strspn(format, " \t\f\r\n\v");
-                str += strspn(str, " \t\f\r\n\v");
+                skip_whitespace(&format);
+                skip_whitespace(&str);
                 if (*str == 0) return parsed;
                 continue;
             }
@@ -141,7 +148,7 @@ extern "C"
                 format++;
                 if (*format == '%')
                 {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     goto normal;
                 }
 
@@ -154,8 +161,8 @@ extern "C"
                 switch (specifier)
                 {
                 case 's': {
-                    str += strspn(str, " \t\f\r\n\v");
-                    size_t chars = strcspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
+                    size_t chars = strcspn(str, WHITESPACE_CHARACTERS);
                     if (!chars) return parsed;
                     if ((flags & FLAG_WIDTH) && chars > width) chars = width;
                     if (!(flags & FLAG_DISCARD))
@@ -197,28 +204,28 @@ extern "C"
                     break;
                 }
                 case 'd': {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     ssize_t value = scan_signed_integer(&str, 10);
                     if (!(flags & FLAG_DISCARD)) write_parsed_signed_integer(value, flags, ap);
                     parsed++;
                     break;
                 }
                 case 'i': {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     ssize_t value = scan_signed_integer(&str, 0);
                     if (!(flags & FLAG_DISCARD)) write_parsed_signed_integer(value, flags, ap);
                     parsed++;
                     break;
                 }
                 case 'o': {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     size_t value = scan_unsigned_integer(&str, 8);
                     if (!(flags & FLAG_DISCARD)) write_parsed_unsigned_integer(value, flags, ap);
                     parsed++;
                     break;
                 }
                 case 'u': {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     size_t value = scan_unsigned_integer(&str, 10);
                     if (!(flags & FLAG_DISCARD)) write_parsed_unsigned_integer(value, flags, ap);
                     parsed++;
@@ -226,14 +233,14 @@ extern "C"
                 }
                 case 'X':
                 case 'x': {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     size_t value = scan_unsigned_integer(&str, 16);
                     if (!(flags & FLAG_DISCARD)) write_parsed_unsigned_integer(value, flags, ap);
                     parsed++;
                     break;
                 }
                 case 'p': {
-                    str += strspn(str, " \t\f\r\n\v");
+                    skip_whitespace(&str);
                     size_t value = scan_unsigned_integer(&str, 16);
                     if (!(flags & FLAG_DISCARD)) *va_arg(ap, void**) = (void*)value;
                     parsed++;