filesystem stuff and experimenting with userspace tasks

3 files changed, 41 insertions, 13 deletions

diff --git a/userspace/foolshell.c b/userspace/foolshell.c
index bf0501f..2abb549 100644
--- a/userspace/foolshell.c
+++ b/userspace/foolshell.c
@@ -227,7 +227,7 @@ int process(char *buf)
 	int pid=fork();
 	if(pid!=0)
 	{
-//	    printf("new task pid: %i \n",pid);
+	    printf("new task pid: %i \n",pid);
 	}
 	if(pid==0)
 	{
diff --git a/userspace/sys/syscalls.c b/userspace/sys/syscalls.c
index e6a6a4d..9dfd313 100644
--- a/userspace/sys/syscalls.c
+++ b/userspace/sys/syscalls.c
@@ -92,8 +92,6 @@ int gettimeofday(struct timeval *tv, void *tz)
     return syscall(SYSCALL_GETTIMEOFDAY,tv,tz,0);
 }
 
-
-
 int fork(void)
 {
     return syscall(SYSCALL_FORK,0,0,0);
@@ -109,9 +107,6 @@ int kill(int pid, int sig)
     return syscall(SYSCALL_KILL,pid,sig,0);
 }
 
-
-
-
 int link(char *old, char *ne)
 {
     return syscall(SYSCALL_LINK,old,ne,0);
@@ -122,20 +117,16 @@ int unlink(char *name)
     return syscall(SYSCALL_UNLINK,name,0,0);
 }
 
-
-
 int times(struct tms *buf)
 {
     return syscall(SYSCALL_TIMES,buf,0,0);
 }
 
-
 int wait(int *status)
 {
     return syscall(SYSCALL_WAIT,status,0,0);
 }
 
-
 int stat(const char *file, struct stat *st)
 {
     return syscall(SYSCALL_STAT,file,st,0);
diff --git a/userspace/task1.c b/userspace/task1.c
index d3706ee..d9875f4 100644
--- a/userspace/task1.c
+++ b/userspace/task1.c
@@ -1,11 +1,48 @@
-int main(int argc, char **argv)
+typedef unsigned long long ULL;
+
+// a simple cache to speedup successive requests!
+static ULL fib1_cached_index=0;
+static ULL fib1_cached_value=0;
+
+static ULL fib2_cached_index=1;
+static ULL fib2_cached_value=1;
+
+
+ULL fib(ULL i)
 {
-    signed int i=0;
+    if(i==0)return 0;
+    if(i==1)return 1;
+    if(i==fib1_cached_index)return fib1_cached_value;
+    if(i==fib2_cached_index)return fib2_cached_value;
+
+    ULL value=fib(i-1)+fib(i-2);
+
+    fib1_cached_index=fib2_cached_index;
+    fib1_cached_value=fib2_cached_value;
+
+    fib2_cached_index=i;
+    fib2_cached_value=value;
+
+    return value;
+}
+
+
+
+int main(unsigned int argc, char **argv)
+{
+    ULL i=0;
 
     while(1)
     {
 	i++;
-	printf("task 1 : %i \n",i);
+
+	fib(i); //precalc
+
+	// this will exhaust the stack so we call fib every time above
+	#ifdef __linux__
+	    if((i%100000000)==1)printf("gcc-fibonacci(%llu) = %llu \n",i,fib(i));
+	#endif
+	    if((i%100000000)==1)printf("fibonacci(%u...) = %u... \n",(unsigned)i,(unsigned)fib(i));
     }
 
     return 0;