syscalls: ftruncate

kernel-src/sys/syscalls/truncate.c

@@ -0,0 +1,27 @@
+#include <kernel/syscalls.h>
+
+syscallret_t syscall_ftruncate(int fd, size_t size) {
+	syscallret_t ret = {
+		.ret = -1
+	};
+
+	file_t *file = fd_get(fd);
+	if (file == NULL) {
+		ret.errno = EBADF;
+		return ret;
+	}
+
+	if ((file->flags & FILE_WRITE) == 0 || file->vnode->type != V_TYPE_REGULAR) {
+		ret.errno = EINVAL;
+		goto cleanup;
+	}
+
+	ret.errno = VOP_RESIZE(file->vnode, size, &_cpu()->thread->proc->cred);
+	ret.ret = ret.errno ? -1 : 0;
+
+	cleanup:
+
+	fd_release(file);
+
+	return ret;	
+}