Re: [OpenWrt-Devel] [PATCH v2] procd: delay inittab workers until the tty exists.

2015-01-21 Thread Owen Kirby 

John,

On 15-01-19 10:34 PM, John Crispin wrote:


On 20/01/2015 01:21, Owen Kirby wrote:

Add hotplug support for tty devices in /etc/inittab that are specified
by the askfirst
keyword so that terminals attached after boot time get console processes
started.

This was tested on an AT91 target using the gadget serial subsystem and
on an WNDR3800
with a USB serial adapter. One possible weirdness I encountered was that
the baud rates
and control modes sometimes need adjusting with a hotplug script after
reconnecting
the adapter. This is also only implemented for askfirst, but it might
also make sense
to do the same thing for respawn and askconsole.



i think it would be a lot simpler if you ...

* add a new cmd_handler inside hotplug/json_script called console or
spawn_console
* add a 2nd parameter to procd_inittab_run called char *tty that can be
NULL or act as a filter
* call procd_inittab_run with the 2nd parameter set from the new
json_script handler
* add a new if clause to package/system/procd/files/hotplug.json
I'm not sure that would really be any simpler. The cmd_handler would 
need to deal with respawning the console process and would wind up 
duplicating a the code already in inittab.c. It seemed like less work to 
simply extend the hotplug system to add a way for the inittab.c code to 
receive notifications of hotplug events. There is also the question of 
where this 2nd parameter to procd_inittab_run would come from, would we 
need to parse the /etc/hotplug.json script for anything that might spawn 
a console, and what if there were multiple consoles created this way in 
the hotplug script?


Furthermore, it seems like the description of which tty devices should 
spawn consoles and which devices don't is really a board-specific 
configuration item that seems inappropriate to put into /etc/hotplug.json.


Although, adding a new cmd_handler for creating consoles is an 
interesting idea. We could get rid of /etc/inittab entirely by creating 
all the consoles that way.


But, if you really think that's the best approach then I'll code up a 
3rd version of the patch for you.


Cheers,
Owen
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[OpenWrt-Devel] [PATCH v2] procd: delay inittab workers until the tty exists.

2015-01-19 Thread Owen Kirby 

Add hotplug support for tty devices in /etc/inittab that are specified by the 
askfirst
keyword so that terminals attached after boot time get console processes 
started.

This was tested on an AT91 target using the gadget serial subsystem and on an 
WNDR3800
with a USB serial adapter. One possible weirdness I encountered was that the 
baud rates
and control modes sometimes need adjusting with a hotplug script after 
reconnecting
the adapter. This is also only implemented for askfirst, but it might also make 
sense
to do the same thing for respawn and askconsole.

Signed-off-by: Owen Kirby o...@exegin.com
---
 inittab.c  | 35 ---
 plug/hotplug.c | 40 +++-
 plug/hotplug.h | 15 +++
 3 files changed, 82 insertions(+), 8 deletions(-)

diff --git a/inittab.c b/inittab.c
index 623103d..c9310e5 100644
--- a/inittab.c
+++ b/inittab.c
@@ -26,6 +26,7 @@
 #include libubox/utils.h
 #include libubox/list.h
 
+#include plug/hotplug.h

 #include utils/utils.h
 #include procd.h
 #include rcS.h
@@ -55,6 +56,7 @@ struct init_action {
 
 	struct init_handler *handler;

struct uloop_process proc;
+   struct hotplug_event event;
 
 	int respawn;

struct uloop_timeout tout;
@@ -90,6 +92,29 @@ static int dev_exist(const char *dev)
return (res != -1);
 }
 
+static void dev_hotplug(struct hotplug_event *event, struct blob_attr *msg)

+{
+   struct init_action *a = container_of(event, struct init_action, event);
+   char *action = hotplug_msg_find_var(msg, ACTION);
+   char *subsystem = hotplug_msg_find_var(msg, SUBSYSTEM);
+   char *devname = hotplug_msg_find_var(msg, DEVNAME);
+   
+   if (!action || !subsystem || !devname)
+   return;
+   if (strcmp(subsystem, tty) || strcmp(devname, a-id))
+   return;
+   
+   DEBUG(4, inittab hotplug: ACTION=\%s\, SUBSYSTEM=\%s\, 
DEVNAME=\%s\\n,
+   action, subsystem, devname);
+   if (!strcmp(action, add)) {
+   uloop_timeout_set(a-tout, a-respawn);
+   }
+   else if (!strcmp(action, remove)) {
+   uloop_process_delete(a-proc);
+   uloop_timeout_cancel(a-tout);
+   }
+}
+
 static void fork_worker(struct init_action *a)
 {
int fd;
@@ -130,7 +155,7 @@ static void child_exit(struct uloop_process *proc, int ret)
struct init_action *a = container_of(proc, struct init_action, proc);
 
 	DEBUG(4, pid:%d\n, proc-pid);

-uloop_timeout_set(a-tout, a-respawn);
+   uloop_timeout_set(a-tout, a-respawn);
 }
 
 static void respawn(struct uloop_timeout *tout)

@@ -157,7 +182,7 @@ static void askfirst(struct init_action *a)
 {
int i;
 
-	if (!dev_exist(a-id) || (console  !strcmp(console, a-id))) {

+   if (console  !strcmp(console, a-id)) {
DEBUG(4, Skipping %s\n, a-id);
return;
}
@@ -168,8 +193,12 @@ static void askfirst(struct init_action *a)
a-argv[0] = ask;
a-respawn = 500;
 
+	a-event.cb = dev_hotplug;

+   hotplug_event_add(a-event);
+
a-proc.cb = child_exit;
-   fork_worker(a);
+   if (dev_exist(a-id))
+   fork_worker(a);
 }
 
 static void askconsole(struct init_action *a)

diff --git a/plug/hotplug.c b/plug/hotplug.c
index 061833a..3aa87c0 100644
--- a/plug/hotplug.c
+++ b/plug/hotplug.c
@@ -44,13 +44,14 @@ struct cmd_queue {
 };
 
 static LIST_HEAD(cmd_queue);

+static LIST_HEAD(events);
 static struct uloop_process queue_proc;
 static struct uloop_timeout last_event;
 static struct blob_buf b;
 static char *rule_file;
 static struct blob_buf script;
 
-static char *hotplug_msg_find_var(struct blob_attr *msg, const char *name)

+char *hotplug_msg_find_var(struct blob_attr *msg, const char *name)
 {
struct blob_attr *cur;
int rem;
@@ -393,24 +394,30 @@ static struct json_script_ctx jctx = {
.handle_file = rule_handle_file,
 };
 
-static void hotplug_handler_debug(struct blob_attr *data)

+static void hotplug_handler_debug(struct hotplug_event *e, struct blob_attr 
*msg)
 {
char *str;
 
 	if (debug  3)

return;
 
-	str = blobmsg_format_json(data, true);

+   str = blobmsg_format_json(msg, true);
DEBUG(3, %s\n, str);
free(str);
 }
 
+static void hotplug_handler_script(struct hotplug_event *e, struct blob_attr *msg)

+{
+   json_script_run(jctx, rule_file, msg);
+}
+
 static void hotplug_handler(struct uloop_fd *u, unsigned int ev)
 {
int i = 0;
static char buf[4096];
int len = recv(u-fd, buf, sizeof(buf), MSG_DONTWAIT);
void *index;
+   struct hotplug_event *e, *tmp;
if (len  1)
return;
 
@@ -427,10 +434,16 @@ static void hotplug_handler(struct uloop_fd *u, unsigned int ev)

i += l;
}
blobmsg_close_table(b, index);
-   hotplug_handler_debug(b.head);
-

Re: [OpenWrt-Devel] [PATCH v2] procd: delay inittab workers until the tty exists.

2015-01-19 Thread John Crispin 


On 20/01/2015 01:21, Owen Kirby wrote:
 Add hotplug support for tty devices in /etc/inittab that are specified
 by the askfirst
 keyword so that terminals attached after boot time get console processes
 started.
 
 This was tested on an AT91 target using the gadget serial subsystem and
 on an WNDR3800
 with a USB serial adapter. One possible weirdness I encountered was that
 the baud rates
 and control modes sometimes need adjusting with a hotplug script after
 reconnecting
 the adapter. This is also only implemented for askfirst, but it might
 also make sense
 to do the same thing for respawn and askconsole.
 


i think it would be a lot simpler if you ...

* add a new cmd_handler inside hotplug/json_script called console or
spawn_console
* add a 2nd parameter to procd_inittab_run called char *tty that can be
NULL or act as a filter
* call procd_inittab_run with the 2nd parameter set from the new
json_script handler
* add a new if clause to package/system/procd/files/hotplug.json




 Signed-off-by: Owen Kirby o...@exegin.com
 ---
  inittab.c  | 35 ---
  plug/hotplug.c | 40 +++-
  plug/hotplug.h | 15 +++
  3 files changed, 82 insertions(+), 8 deletions(-)
 
 diff --git a/inittab.c b/inittab.c
 index 623103d..c9310e5 100644
 --- a/inittab.c
 +++ b/inittab.c
 @@ -26,6 +26,7 @@
  #include libubox/utils.h
  #include libubox/list.h
  
 +#include plug/hotplug.h
  #include utils/utils.h
  #include procd.h
  #include rcS.h
 @@ -55,6 +56,7 @@ struct init_action {
  
  struct init_handler *handler;
  struct uloop_process proc;
 +struct hotplug_event event;
  
  int respawn;
  struct uloop_timeout tout;
 @@ -90,6 +92,29 @@ static int dev_exist(const char *dev)
  return (res != -1);
  }
  
 +static void dev_hotplug(struct hotplug_event *event, struct blob_attr
 *msg)
 +{
 +struct init_action *a = container_of(event, struct init_action,
 event);
 +char *action = hotplug_msg_find_var(msg, ACTION);
 +char *subsystem = hotplug_msg_find_var(msg, SUBSYSTEM);
 +char *devname = hotplug_msg_find_var(msg, DEVNAME);
 +   
 +if (!action || !subsystem || !devname)
 +return;
 +if (strcmp(subsystem, tty) || strcmp(devname, a-id))
 +return;
 +   
 +DEBUG(4, inittab hotplug: ACTION=\%s\, SUBSYSTEM=\%s\,
 DEVNAME=\%s\\n,
 +action, subsystem, devname);
 +if (!strcmp(action, add)) {
 +uloop_timeout_set(a-tout, a-respawn);
 +}
 +else if (!strcmp(action, remove)) {
 +uloop_process_delete(a-proc);
 +uloop_timeout_cancel(a-tout);
 +}
 +}
 +
  static void fork_worker(struct init_action *a)
  {
  int fd;
 @@ -130,7 +155,7 @@ static void child_exit(struct uloop_process *proc,
 int ret)
  struct init_action *a = container_of(proc, struct init_action, proc);
  
  DEBUG(4, pid:%d\n, proc-pid);
 -uloop_timeout_set(a-tout, a-respawn);
 +uloop_timeout_set(a-tout, a-respawn);
  }
  
  static void respawn(struct uloop_timeout *tout)
 @@ -157,7 +182,7 @@ static void askfirst(struct init_action *a)
  {
  int i;
  
 -if (!dev_exist(a-id) || (console  !strcmp(console, a-id))) {
 +if (console  !strcmp(console, a-id)) {
  DEBUG(4, Skipping %s\n, a-id);
  return;
  }
 @@ -168,8 +193,12 @@ static void askfirst(struct init_action *a)
  a-argv[0] = ask;
  a-respawn = 500;
  
 +a-event.cb = dev_hotplug;
 +hotplug_event_add(a-event);
 +
  a-proc.cb = child_exit;
 -fork_worker(a);
 +if (dev_exist(a-id))
 +fork_worker(a);
  }
  
  static void askconsole(struct init_action *a)
 diff --git a/plug/hotplug.c b/plug/hotplug.c
 index 061833a..3aa87c0 100644
 --- a/plug/hotplug.c
 +++ b/plug/hotplug.c
 @@ -44,13 +44,14 @@ struct cmd_queue {
  };
  
  static LIST_HEAD(cmd_queue);
 +static LIST_HEAD(events);
  static struct uloop_process queue_proc;
  static struct uloop_timeout last_event;
  static struct blob_buf b;
  static char *rule_file;
  static struct blob_buf script;
  
 -static char *hotplug_msg_find_var(struct blob_attr *msg, const char *name)
 +char *hotplug_msg_find_var(struct blob_attr *msg, const char *name)
  {
  struct blob_attr *cur;
  int rem;
 @@ -393,24 +394,30 @@ static struct json_script_ctx jctx = {
  .handle_file = rule_handle_file,
  };
  
 -static void hotplug_handler_debug(struct blob_attr *data)
 +static void hotplug_handler_debug(struct hotplug_event *e, struct
 blob_attr *msg)
  {
  char *str;
  
  if (debug  3)
  return;
  
 -str = blobmsg_format_json(data, true);
 +str = blobmsg_format_json(msg, true);
  DEBUG(3, %s\n, str);
  free(str);
  }
  
 +static void hotplug_handler_script(struct hotplug_event *e, struct
 blob_attr *msg)
 +{
 +json_script_run(jctx, rule_file, msg);
 +}
 +
  static void hotplug_handler(struct uloop_fd *u, unsigned int ev)
  {
  int i = 0;
  static char buf[4096];