apps: Add more simple apps

Now that we can start them at will from the command line, bring them on!!

apps/Makefile

@@ -1,4 +1,4 @@
-APPS := init sym sh
+APPS := init sym sh crash uname uptime
 
 APPS_DIR := $(LUNA_ROOT)/apps
 APPS_SRC := $(APPS_DIR)/src

apps/src/crash.c

@@ -0,0 +1,5 @@
+int main()
+{
+    int* ptr = (int*)0xdeadbeef;
+    *ptr = 6;
+}

apps/src/init.c

@@ -1,43 +1,8 @@
 #include <luna.h>
-#include <setjmp.h>
 #include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/stat.h>
 #include <sys/wait.h>
 #include <unistd.h>
 
-int print_version()
-{
-    char version[4096];
-
-    FILE* fp = fopen("/dev/version", "r");
-    if (!fp)
-    {
-        perror("fopen");
-        return 1;
-    }
-
-    size_t nread = fread(version, 4096, 1, fp);
-    if (ferror(fp))
-    {
-        perror("fread");
-        return 1;
-    }
-
-    version[nread] = 0;
-
-    if (fclose(fp) < 0)
-    {
-        perror("fclose");
-        return 1;
-    }
-
-    printf("Your kernel version is %s\n\n", version);
-
-    return 0;
-}
-
 int main()
 {
     if (getpid() != 1)
@@ -46,11 +11,7 @@ int main()
         return 1;
     }
 
-    printf("Welcome to Luna!\n");
+    printf("Welcome to Luna!\n\n");
-
-    printf("Running as PID %ld\n", getpid());
-
-    if (print_version()) return 1;
 
     msleep(200);
 

apps/src/uname.c

@@ -0,0 +1,26 @@
+#include <stdio.h>
+
+int main()
+{
+    FILE* fp = fopen("/dev/version", "r");
+    if (!fp)
+    {
+        perror("fopen");
+        return 1;
+    }
+
+    char buf[4096];
+    size_t nread = fread(buf, sizeof(buf) - 1, 1, fp);
+
+    if (ferror(fp))
+    {
+        perror("fread");
+        return 1;
+    }
+
+    buf[nread] = 0; // null terminate it :)
+
+    printf("%s\n", buf);
+
+    fclose(fp);
+}

apps/src/uptime.c

@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main()
+{
+    FILE* fp = fopen("/dev/uptime", "r");
+    if (!fp)
+    {
+        perror("fopen");
+        return 1;
+    }
+
+    char buf[4096];
+    size_t nread = fread(buf, sizeof(buf) - 1, 1, fp);
+
+    if (ferror(fp))
+    {
+        perror("fread");
+        return 1;
+    }
+
+    buf[nread] = 0; // null terminate it :)
+
+    long ms_uptime = atol(buf);
+
+    printf("up for %ld seconds\n", ms_uptime / 1000);
+
+    fclose(fp);
+}