标准函数

29_day/stdlib/stdlib.c

@@ -0,0 +1,51 @@
+#include "../apilib.h"
+#include "../stdlib.h"
+
+#include <stdio.h>
+#include <stdarg.h>
+
+int putchar(int c)
+{
+	api_putchar(c);
+	return c;
+}
+
+void exit(int status)
+{
+	api_end();
+}
+
+int printf(char *format, ...)
+{
+	va_list ap;
+	char s[1000];
+	int i;
+
+	va_start(ap, format);
+	i = vsprintf(s, format, ap);
+	api_putstr0(s);
+	va_end(ap);
+	return i;
+}
+
+void *malloc(int size)
+{
+	char *p = api_malloc(size + 16);
+	if (p != 0) {
+		*((int *) p) = size;
+		p += 16;
+	}
+	return p;
+}
+
+void free(void *p)
+{
+	char *q = p;
+	int size;
+	if (q != 0) {
+		q -= 16;
+		size = *((int *) q);
+		api_free(q, size + 16);
+	}
+	return;
+}