From: heinzm@redhat.com <heinzm@redhat.com> Date: Wed, 27 Aug 2008 14:16:39 +0200 Subject: [md] add device-mapper message parser interface Message-id: 20080827121637.427194187@redhat.com O-Subject: [PATCH RHEL5.3 437180 03/11] dm-message.h.patch Bugzilla: 437180 This patch introduces the device-mapper message parser interface. It allows for parsing message strings calling callback functions with parsed parameters being passed to those. Heinz Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> diff --git a/drivers/md/dm-message.h b/drivers/md/dm-message.h new file mode 100644 index 0000000..ddc52c7 --- /dev/null +++ b/drivers/md/dm-message.h @@ -0,0 +1,89 @@ +/* + * Copyright (C) 2007,2008 Red Hat, Inc. All rights reserved. + * + * Module Author: Heinz Mauelshagen <heinzm@redhat.com> + * + * This file is released under the GPL. + * + */ + +#ifndef DM_MESSAGE_H +#define DM_MESSAGE_H + +/* Factor out to dm.h. */ +/* Reference to array end. */ +#define ARRAY_END(a) ((a) + ARRAY_SIZE(a)) + +/* Message return bits. */ +enum dm_message_return { + dm_msg_ret_ambiguous, /* Action ambiguous. */ + dm_msg_ret_inval, /* Action invalid. */ + dm_msg_ret_undef, /* Action undefined. */ + + dm_msg_ret_option, /* Option error. */ + dm_msg_ret_arg, /* Argument error. */ + dm_msg_ret_argcount, /* Argument count error. */ +}; + +/* Message argument type conversions. */ +enum dm_message_argument_type { + dm_msg_base_t, /* Basename string. */ + dm_msg_str_t, /* String. */ + dm_msg_int_t, /* Signed int. */ + dm_msg_uint_t, /* Unsigned int. */ + dm_msg_uint64_t, /* Unsigned int 64. */ +}; + +/* A message option. */ +struct dm_message_option { + unsigned num_options; + char **options; + unsigned long *actions; +}; + +/* Message arguments and types. */ +struct dm_message_argument { + unsigned num_args; + unsigned long **ptr; + enum dm_message_argument_type types[]; +}; + +/* Client message. */ +struct dm_msg { + unsigned long action; /* Identified action. */ + unsigned long ret; /* Return bits. */ + unsigned num_specs; /* # of sepcifications listed. */ + struct dm_msg_spec *specs; /* Specification list. */ + struct dm_msg_spec *spec; /* Specification selected. */ +}; + +/* Secification of the message. */ +struct dm_msg_spec { + const char *cmd; /* Name of the command (i.e. 'bandwidth'). */ + unsigned long action; + struct dm_message_option *options; + struct dm_message_argument *args; + unsigned long parm; /* Parameter to pass through to callback. */ + /* Function to process for action. */ + int (*f) (struct dm_msg *msg, void *context); +}; + +/* Parameter access macros. */ +#define DM_MSG_PARM(msg) ((msg)->spec->parm) + +#define DM_MSG_STR_ARGS(msg, idx) ((char*) *(msg)->spec->args->ptr[idx]) +#define DM_MSG_INT_ARGS(msg, idx) ((int) *(msg)->spec->args->ptr[idx]) +#define DM_MSG_UINT_ARGS(msg, idx) ((unsigned) DM_MSG_INT_ARG(msg, idx)) +#define DM_MSG_UINT64_ARGS(msg, idx) ((uint64_t) *(msg)->spec->args->ptr[idx]) + +#define DM_MSG_STR_ARG(msg) DM_MSG_STR_ARGS(msg, 0) +#define DM_MSG_INT_ARG(msg) DM_MSG_INT_ARGS(msg, 0) +#define DM_MSG_UINT_ARG(msg) DM_MSG_UINT_ARGS(msg, 0) +#define DM_MSG_UINT64_ARG(msg) DM_MSG_UINT64_ARGS(msg, 0) + + +/* Parse a message and its options and optionally call a function back. */ +int dm_message_parse(const char *caller, struct dm_msg *msg, void *context, + int argc, char **argv); + +#endif