syscalls: fork

src/sys/syscalls/fork.c

@@ -0,0 +1,62 @@
+#include <kernel/syscalls.h>
+#include <kernel/vmm.h>
+#include <errno.h>
+#include <arch/spinlock.h>
+#include <kernel/sched.h>
+#include <arch/cls.h>
+#include <arch/regs.h>
+
+syscallret syscall_fork(arch_regs* ctx){
+	
+	syscallret retv;
+	retv.ret = -1;
+	thread_t* newthread = sched_newuthread(NULL, PAGE_SIZE*10, NULL, NULL, false, THREAD_PRIORITY_USER);
+	
+	if(!newthread){
+		retv.errno = ENOMEM;
+		return retv;
+	}
+	
+	proc_t* newproc = newthread->proc;
+	thread_t* thread = arch_getcls()->thread;
+	proc_t* proc = thread->proc;
+
+	spinlock_acquire(&proc->lock);		
+
+	fd_tableclone(&proc->fdtable, &newproc->fdtable);
+
+	int err = vmm_fork(thread->ctx, newthread->ctx);
+
+	if(err){
+		printf("fork: VMM_FORK FAILED BUT THREAD DEALLOCATION IS NOT SUPPORTED YET!\n");
+		retv.errno = err;
+		return retv;
+	}
+
+	newproc->parent = proc;
+	newproc->sibling = proc->child;
+       	proc->child = newproc;	
+	newproc->gid = proc->gid;
+	newproc->uid = proc->uid;
+
+	vfs_acquirenode(proc->root);
+	vfs_acquirenode(proc->cwd);
+
+	newproc->root = proc->root;
+	newproc->cwd  = proc->cwd;
+
+	memcpy(newthread->regs, ctx, sizeof(arch_regs));
+	arch_regs_saveextra(&newthread->extraregs);
+
+	arch_regs_setret(newthread->regs, 0);
+	arch_regs_seterrno(newthread->regs, 0);
+
+	spinlock_release(&proc->lock);
+
+	sched_queuethread(newthread);
+
+	retv.errno = 0;
+	retv.ret = newproc->pid;
+	return retv;
+
+}