Lab 1

user/sendpage.c

@@ -0,0 +1,39 @@
+// Test Conversation between parent and child environment
+// Contributed by Varun Agrawal at Stony Brook
+
+#include <inc/lib.h>
+
+const char *str1 = "hello child environment! how are you?";
+const char *str2 = "hello parent environment! I'm good.";
+
+#define TEMP_ADDR	((char*)0xa00000)
+#define TEMP_ADDR_CHILD	((char*)0xb00000)
+
+void
+umain(int argc, char **argv)
+{
+	envid_t who;
+
+	if ((who = fork()) == 0) {
+		// Child
+		ipc_recv(&who, TEMP_ADDR_CHILD, 0);
+		cprintf("%x got message: %s\n", who, TEMP_ADDR_CHILD);
+		if (strncmp(TEMP_ADDR_CHILD, str1, strlen(str1)) == 0)
+			cprintf("child received correct message\n");
+
+		memcpy(TEMP_ADDR_CHILD, str2, strlen(str2) + 1);
+		ipc_send(who, 0, TEMP_ADDR_CHILD, PTE_P | PTE_W | PTE_U);
+		return;
+	}
+
+	// Parent
+	sys_page_alloc(thisenv->env_id, TEMP_ADDR, PTE_P | PTE_W | PTE_U);
+	memcpy(TEMP_ADDR, str1, strlen(str1) + 1);
+	ipc_send(who, 0, TEMP_ADDR, PTE_P | PTE_W | PTE_U);
+
+	ipc_recv(&who, TEMP_ADDR, 0);
+	cprintf("%x got message: %s\n", who, TEMP_ADDR);
+	if (strncmp(TEMP_ADDR, str2, strlen(str2)) == 0)
+		cprintf("parent received correct message\n");
+	return;
+}