1 files changed, 101 insertions, 0 deletions
diff --git a/src/libc/stdio.c b/src/libc/stdio.c
index 9fdf510..e0b87a8 100644
--- a/src/libc/stdio.c
+++ b/src/libc/stdio.c
@@ -150,6 +150,107 @@ int vprintf( const char *format, va_list args )
 	return n;
 }
 
+int snprintf( char *buf, size_t n, const char *format, ... )
+{
+	va_list args;
+	
+	va_start( args, format );
+	int res = vsnprintf( buf, n, format, args );
+	va_end( args );
+	
+	return res;
+}
+
+#define EMIT( x ) if( len < n ) { *buf = ( x ); buf++; *buf = '\0'; len++; }
+
+#define APPEND_STRING( s, s2 ) \
+	strlcat( s, s2, n - len ); \
+	s += strlen( s2 ); \
+	len += strlen( s2 ); \
+	if( len < n ) { \
+		*s = '\0'; \
+	}
+
+int vsnprintf( char *buf, size_t n, const char *format, va_list args )
+{
+	const char *s = format;
+	int len = 0;
+
+	*buf = '\0';	
+	while( *s != '\0' && len < n ) {
+		switch( *s ) {
+			case '\n':
+				EMIT( '\n' );
+				break;
+			
+			case '%':
+				s++;
+				if( *s == '\0' ) {
+					strlcpy( buf, "<truncated % found at end of format string>", n - len );
+					strlcat( buf, "\n", n - len - 1 );
+					return -1;
+				}
+				
+				switch( *s ) {
+					case '%':
+						EMIT( '%' );
+						break;
+						
+					case 'X': {
+						char buf2[19];
+						itoa( va_arg( args, int ), (char *)buf2, 16 );
+						APPEND_STRING( buf, buf2 );
+						}
+						break;
+					
+					case 'd': {
+						char buf2[19];
+						itoa( va_arg( args, int ), (char *)buf2, 10 );
+						APPEND_STRING( buf, buf2 );
+						}
+						break;
+
+					case 'c': {
+						char buf2[2];
+						buf2[0] = (char)va_arg( args, int );
+						buf2[1] = '\0';
+						APPEND_STRING( buf, buf2 );
+						}
+						break;
+						
+					case 's': {
+						const char *s = va_arg( args, const char * );
+						APPEND_STRING( buf, s );
+						}
+						break;
+
+					default: {
+						APPEND_STRING( buf, "<illegal format string %" );
+						char buf2[2];
+						buf2[0] = (char)( *s );
+						buf2[1] = '\0';
+						APPEND_STRING( buf, buf2 );
+						buf2[0] = '\n';
+						APPEND_STRING( buf, buf2 );
+						}
+				}
+				
+				break;				
+			
+			default: {
+				char buf2[2];
+				buf2[0] = (char)( *s );
+				buf2[1] = '\0';
+				APPEND_STRING( buf, buf2 );
+				}
+		}
+		s++;
+	}
+	
+	return len;
+}
+
+
 #ifdef OS_ABAOS
 void __stdio_set_console( console_t *console )
 {