package/swconfig/src/swlib.h

   1 /*
   2  * swlib.h: Switch configuration API (user space part)
   3  *
   4  * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public License
   8  * version 2.1 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15
  16 Usage of the library functions:
  17
  18   The main datastructure for a switch is the struct switch_device
  19   To get started, you first need to use switch_connect() to probe
  20   for switches and allocate an instance of this struct.
  21
  22   There are two possible usage modes:
  23     dev = switch_connect("eth0");
  24       - this call will look for a switch registered for the linux device
  25           "eth0" and only allocate a switch_device for this particular switch.
  26
  27     dev = switch_connect(NULL)
  28       - this will return one switch_device struct for each available
  29           switch. The switch_device structs are chained with by ->next pointer
  30
  31   Then to query a switch for all available attributes, use:
  32     swlib_scan(dev);
  33
  34   All allocated datastructures for the switch_device struct can be freed with
  35     swlib_free(dev);
  36   or
  37     swlib_free_all(dev);
  38
  39   The latter traverses a whole chain of switch_device structs and frees them all
  40
  41   Switch attributes (struct switch_attr) are divided into three groups:
  42     dev->ops:
  43       - global settings
  44     dev->port_ops:
  45       - per-port settings
  46     dev->vlan_ops:
  47       - per-vlan settings
  48
  49   switch_lookup_attr() is a small helper function to locate attributes
  50   by name.
  51
  52   switch_set_attr() and switch_get_attr() can alter or request the values
  53   of attributes.
  54
  55 Usage of the switch_attr struct:
  56
  57   ->atype: attribute group, one of:
  58     - SWLIB_ATTR_GROUP_GLOBAL
  59     - SWLIB_ATTR_GROUP_VLAN
  60     - SWLIB_ATTR_GROUP_PORT
  61
  62   ->id: identifier for the attribute
  63
  64   ->type: data type, one of:
  65     - SWITCH_TYPE_INT
  66     - SWITCH_TYPE_STRING
  67     - SWITCH_TYPE_PORT
  68
  69   ->name: short name of the attribute
  70   ->description: longer description
  71   ->next: pointer to the next attribute of the current group
  72
  73
  74 Usage of the switch_val struct:
  75
  76   When setting attributes, following members of the struct switch_val need
  77   to be set up:
  78
  79     ->len (for attr->type == SWITCH_TYPE_PORT)
  80     ->port_vlan:
  81       - port number (for attr->atype == SWLIB_ATTR_GROUP_PORT), or:
  82       - vlan number (for attr->atype == SWLIB_ATTR_GROUP_VLAN)
  83     ->value.i (for attr->type == SWITCH_TYPE_INT)
  84     ->value.s (for attr->type == SWITCH_TYPE_STRING)
  85       - owned by the caller, not stored in the library internally
  86     ->value.ports (for attr->type == SWITCH_TYPE_PORT)
  87       - must point to an array of at lest val->len * sizeof(struct switch_port)
  88
  89   When getting string attributes, val->value.s must be freed by the caller
  90   When getting port list attributes, an internal static buffer is used,
  91   which changes from call to call.
  92
  93  */
  94
  95 #ifndef __SWLIB_H
  96 #define __SWLIB_H
  97
  98 enum swlib_attr_group {
  99         SWLIB_ATTR_GROUP_GLOBAL,
 100         SWLIB_ATTR_GROUP_VLAN,
 101         SWLIB_ATTR_GROUP_PORT,
 102 };
 103
 104 enum swlib_port_flags {
 105         SWLIB_PORT_FLAG_TAGGED = (1 << 0),
 106 };
 107
 108
 109 struct switch_dev;
 110 struct switch_attr;
 111 struct switch_port;
 112 struct switch_val;
 113
 114 struct switch_dev {
 115         int id;
 116         const char *name;
 117         const char *dev_name;
 118         int ports;
 119         int vlans;
 120         struct switch_attr *ops;
 121         struct switch_attr *port_ops;
 122         struct switch_attr *vlan_ops;
 123         struct switch_dev *next;
 124         void *priv;
 125 };
 126
 127 struct switch_val {
 128         struct switch_attr *attr;
 129         int len;
 130         int err;
 131         int port_vlan;
 132         union {
 133                 const char *s;
 134                 int i;
 135                 struct switch_port *ports;
 136         } value;
 137 };
 138
 139 struct switch_attr {
 140         struct switch_dev *dev;
 141         int atype;
 142         int id;
 143         int type;
 144         const char *name;
 145         const char *description;
 146         struct switch_attr *next;
 147 };
 148
 149 struct switch_port {
 150         unsigned int id;
 151         unsigned int flags;
 152 };
 153
 154 /**
 155  * swlib_connect: connect to the switch through netlink
 156  * @name: name of the ethernet interface,
 157  *
 158  * if name is NULL, it connect and builds a chain of all switches
 159  */
 160 struct switch_dev *swlib_connect(const char *name);
 161
 162 /**
 163  * swlib_free: free all dynamically allocated data for the switch connection
 164  * @dev: switch device struct
 165  *
 166  * all members of a switch device chain (generated by swlib_connect(NULL))
 167  * must be freed individually
 168  */
 169 void swlib_free(struct switch_dev *dev);
 170
 171 /**
 172  * swlib_free_all: run swlib_free on all devices in the chain
 173  * @dev: switch device struct
 174  */
 175 void swlib_free_all(struct switch_dev *dev);
 176
 177 /**
 178  * swlib_scan: probe the switch driver for available commands/attributes
 179  * @dev: switch device struct
 180  */
 181 int swlib_scan(struct switch_dev *dev);
 182
 183 /**
 184  * swlib_lookup_attr: look up a switch attribute
 185  * @dev: switch device struct
 186  * @type: global, port or vlan
 187  * @name: name of the attribute
 188  */
 189 struct switch_attr *swlib_lookup_attr(struct switch_dev *dev,
 190                 enum swlib_attr_group atype, const char *name);
 191
 192 /**
 193  * swlib_set_attr: set the value for an attribute
 194  * @dev: switch device struct
 195  * @attr: switch attribute struct
 196  * @val: attribute value pointer
 197  * returns 0 on success
 198  */
 199 int swlib_set_attr(struct switch_dev *dev, struct switch_attr *attr,
 200                 struct switch_val *val);
 201
 202 /**
 203  * swlib_get_attr: get the value for an attribute
 204  * @dev: switch device struct
 205  * @attr: switch attribute struct
 206  * @val: attribute value pointer
 207  * returns 0 on success
 208  * for string attributes, the result string must be freed by the caller
 209  */
 210 int swlib_get_attr(struct switch_dev *dev, struct switch_attr *attr,
 211                 struct switch_val *val);
 212
 213 #endif