kernel: store a pointer to the callback function in .waits4irq

removes `proc.c`'s pointless dependency on `vfs/root.h`

3 files changed, 22 insertions, 21 deletions

diff --git a/src/kernel/proc.c b/src/kernel/proc.c
index 2c4cc5c..e97d5cf 100644
--- a/src/kernel/proc.c
+++ b/src/kernel/proc.c
@@ -6,7 +6,6 @@
 #include <kernel/vfs/mount.h>
 #include <shared/mem.h>
 #include <stdint.h>
-#include <kernel/vfs/root.h> // TODO
 
 struct process *process_first;
 struct process *process_current;
@@ -108,7 +107,7 @@ _Noreturn void process_idle(void) {
 			if (procs[i]->waits4irq.ready()) {
 				/* if this is entered during the first iteration, it indicates a
 				 * kernel bug. this should be logged. TODO? */
-				vfs_root_handler(&procs[i]->waits4irq.req); // TODO this should be a function pointer too
+				procs[i]->waits4irq.callback(procs[i]);
 				process_switch_any();
 			}
 		}
diff --git a/src/kernel/proc.h b/src/kernel/proc.h
index eaa649a..5daef31 100644
--- a/src/kernel/proc.h
+++ b/src/kernel/proc.h
@@ -40,6 +40,7 @@ struct process {
 		struct {
 			struct vfs_request req;
 			bool (*ready)();
+			void (*callback)(struct process *);
 		} waits4irq;
 	};
 	struct vfs_request *handled_req;
diff --git a/src/kernel/vfs/root.c b/src/kernel/vfs/root.c
index 4e49c3c..cdc388f 100644
--- a/src/kernel/vfs/root.c
+++ b/src/kernel/vfs/root.c
@@ -7,6 +7,7 @@
 #include <kernel/util.h>
 #include <kernel/vfs/root.h>
 #include <shared/mem.h>
+#include <stdbool.h>
 
 // TODO move to arch/
 
@@ -47,6 +48,23 @@ static void req_preprocess(struct vfs_request *req, size_t max_len) {
 	assert(req->input.len + req->offset <= max_len);
 }
 
+
+static void wait_callback(struct process *proc) {
+	vfs_root_handler(&proc->waits4irq.req);
+}
+
+static bool wait_setup(struct vfs_request *req, bool *ready, bool (*ready_fn)()) {
+	if (!ready_fn()) {
+		*ready = false;
+		req->caller->state = PS_WAITS4IRQ;
+		req->caller->waits4irq.req = *req;
+		req->caller->waits4irq.ready = ready_fn;
+		req->caller->waits4irq.callback = wait_callback;
+		return true;
+	}
+	return false;
+}
+
 static int handle(struct vfs_request *req, bool *ready) {
 	switch (req->type) {
 		case VFSOP_OPEN:
@@ -88,31 +106,14 @@ static int handle(struct vfs_request *req, bool *ready) {
 					return req->output.len;
 				}
 				case HANDLE_COM1: {
-					// yet another bit of code shared between serial and ps2.
-					// i really should think how i could unite both of those
-					if (!serial_ready()) {
-						*ready = false;
-						req->caller->state = PS_WAITS4IRQ;
-						req->caller->waits4irq.req = *req;
-						req->caller->waits4irq.ready = serial_ready;
-						return -1;
-					}
+					if (wait_setup(req, ready, serial_ready)) return -1;
 					char buf[16];
 					size_t len = serial_read(buf, min(req->output.len, sizeof buf));
 					virt_cpy_to(req->caller->pages, req->output.buf, buf, len);
 					return len;
 				}
 				case HANDLE_PS2: {
-					if (!ps2_ready()) {
-						*ready = false;
-						req->caller->state = PS_WAITS4IRQ;
-						/* not copying any memory, both sides point to the same
-						 * struct. this line's only there so i don't depend on
-						 * struct alignment always staying the same */
-						req->caller->waits4irq.req = *req;
-						req->caller->waits4irq.ready = ps2_ready;
-						return -1;
-					}
+					if (wait_setup(req, ready, ps2_ready)) return -1;
 					uint8_t buf[16];
 					size_t len = ps2_read(buf, min(req->output.len, sizeof buf));
 					virt_cpy_to(req->caller->pages, req->output.buf, buf, len);