VFS ready function and read yielding

3 files changed, 72 insertions, 10 deletions

diff --git a/kernel/features/fs.c b/kernel/features/fs.c
index 13ed0c2..45e744c 100644
--- a/kernel/features/fs.c
+++ b/kernel/features/fs.c
@@ -154,9 +154,32 @@ u32 vfs_write(const char *path, void *buf, u32 offset, u32 count)
 
 u32 vfs_stat(const char *path, struct stat *buf)
 {
-	struct device *dev = vfs_find_dev(path);
-	assert(dev && dev->vfs && dev->vfs->stat);
-	return dev->vfs->stat(path, buf, dev);
+	while (*path == ' ')
+		path++;
+
+	struct mount_info *m = vfs_find_mount_info(path);
+	assert(m && m->dev && m->dev->vfs && m->dev->vfs->stat);
+
+	u32 len = strlen(m->path);
+	if (len > 1)
+		path += len;
+
+	return m->dev->vfs->stat(path, buf, m->dev);
+}
+
+u32 vfs_ready(const char *path)
+{
+	while (*path == ' ')
+		path++;
+
+	struct mount_info *m = vfs_find_mount_info(path);
+	assert(m && m->dev && m->dev->vfs && m->dev->vfs->ready);
+
+	u32 len = strlen(m->path);
+	if (len > 1)
+		path += len;
+
+	return m->dev->vfs->ready(path, m->dev);
 }
 
 void vfs_install(void)
@@ -176,7 +199,7 @@ void device_add(struct device *dev)
 	list_add(devices, dev);
 }
 
-struct device *device_get(u32 id)
+struct device *device_get_by_id(u32 id)
 {
 	struct node *iterator = devices->head;
 	while (iterator) {
@@ -187,11 +210,33 @@ struct device *device_get(u32 id)
 	return NULL;
 }
 
+struct device *device_get_by_name(const char *name)
+{
+	struct node *iterator = devices->head;
+	while (iterator) {
+		if (!strcmp(((struct device *)iterator->data)->name, name))
+			return iterator->data;
+		iterator = iterator->next;
+	}
+	return NULL;
+}
+
 u32 devfs_read(const char *path, void *buf, u32 offset, u32 count, struct device *dev)
 {
-	assert(dev && dev->read);
-	printf("%s - off: %d, cnt: %d, buf: %x, dev %x\n", path, offset, count, buf, dev);
-	return dev->read(buf, offset, count, dev);
+	struct device *target = device_get_by_name(path + 1);
+	if (!target || !target->read)
+		return 0;
+	return target->read(buf, offset, count, dev);
+}
+
+u32 devfs_ready(const char *path, struct device *dev)
+{
+	(void)dev;
+
+	struct device *target = device_get_by_name(path + 1);
+	if (!target || !target->ready)
+		return 0;
+	return target->ready();
 }
 
 void device_install(void)
@@ -201,6 +246,7 @@ void device_install(void)
 	struct vfs *vfs = malloc(sizeof(*vfs));
 	vfs->type = VFS_DEVFS;
 	vfs->read = devfs_read;
+	vfs->ready = devfs_ready;
 	struct device *dev = malloc(sizeof(*dev));
 	dev->name = "dev";
 	dev->type = DEV_CHAR;
@@ -406,3 +452,10 @@ u32 ext2_stat(const char *path, struct stat *buf, struct device *dev)
 
 	return 0;
 }
+
+u32 ext2_ready(const char *path, struct device *dev)
+{
+	(void)path;
+	(void)dev;
+	return 1;
+}
diff --git a/kernel/features/proc.c b/kernel/features/proc.c
index 79bc6c8..8fbb4c5 100644
--- a/kernel/features/proc.c
+++ b/kernel/features/proc.c
@@ -44,8 +44,12 @@ void scheduler(struct regs *regs)
 	} else if (((struct proc *)proc_list->head->data)->state == PROC_RUNNING) {
 		current = proc_list->head;
 	} else {
-		print("TODO: All processes are sleeping!\n"); // TODO!
-		/* loop(); */
+		/* sti(); */
+		/* hlt(); */
+		/* cli(); */
+		//print("TODO: All processes are sleeping!\n"); // TODO!
+		//loop();
+		return;
 	}
 
 	memcpy(regs, &((struct proc *)current->data)->regs, sizeof(struct regs));
diff --git a/kernel/features/syscall.c b/kernel/features/syscall.c
index dbb7033..c5570c3 100644
--- a/kernel/features/syscall.c
+++ b/kernel/features/syscall.c
@@ -37,7 +37,12 @@ void syscall_handler(struct regs *r)
 		break;
 	}
 	case SYS_READ: {
-		r->eax = (u32)vfs_read((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
+		if (vfs_ready((char *)r->ebx)) {
+			r->eax = (u32)vfs_read((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
+		} else {
+			proc_current()->state = PROC_SLEEPING;
+			scheduler(r);
+		}
 		break;
 	}
 	case SYS_WRITE: {