From b41203897a7bfc7ab4a446808494e6216eff7c56 Mon Sep 17 00:00:00 2001 From: Chris Johns Date: Mon, 11 Apr 2016 13:53:58 +1000 Subject: Clean up and review of Networking User Guide. --- networking/using_networking_rtems_app.rst | 1254 ++++++++++++++--------------- 1 file changed, 625 insertions(+), 629 deletions(-) (limited to 'networking/using_networking_rtems_app.rst') diff --git a/networking/using_networking_rtems_app.rst b/networking/using_networking_rtems_app.rst index bd6f9f5..dfc422b 100644 --- a/networking/using_networking_rtems_app.rst +++ b/networking/using_networking_rtems_app.rst @@ -1,3 +1,8 @@ +.. COMMENT: Written by Eric Norum +.. COMMENT: COPYRIGHT (c) 1988-2002. +.. COMMENT: On-Line Applications Research Corporation (OAR). +.. COMMENT: All rights reserved. + Using Networking in an RTEMS Application ######################################## @@ -7,20 +12,20 @@ Makefile changes Including the required managers ------------------------------- -The FreeBSD networking code requires several RTEMS managers -in the application: -.. code:: c +The FreeBSD networking code requires several RTEMS managers in the application: + +.. code-block:: c MANAGERS = io event semaphore Increasing the size of the heap ------------------------------- -The networking tasks allocate a lot of memory. For most applications -the heap should be at least 256 kbytes. -The amount of memory set aside for the heap can be adjusted by setting -the ``CFLAGS_LD`` definition as shown below: -.. code:: c +The networking tasks allocate a lot of memory. For most applications the heap +should be at least 256 kbytes. The amount of memory set aside for the heap can +be adjusted by setting the ``CFLAGS_LD`` definition as shown below: + +.. code-block:: c CFLAGS_LD += -Wl,--defsym -Wl,HeapSize=0x80000 @@ -29,22 +34,20 @@ This sets aside 512 kbytes of memory for the heap. System Configuration ==================== -The networking tasks allocate some RTEMS objects. These -must be accounted for in the application configuration table. The following -lists the requirements. +The networking tasks allocate some RTEMS objects. These must be accounted for +in the application configuration table. The following lists the requirements. *TASKS* One network task plus a receive and transmit task for each device. *SEMAPHORES* - One network semaphore plus one syslog mutex semaphore if the application uses - openlog/syslog. + One network semaphore plus one syslog mutex semaphore if the application + uses openlog/syslog. *EVENTS* - The network stack uses ``RTEMS_EVENT_24`` and ``RTEMS_EVENT_25``. - This has no effect on the application configuration, but - application tasks which call the network functions should not - use these events for other purposes. + The network stack uses ``RTEMS_EVENT_24`` and ``RTEMS_EVENT_25``. This has + no effect on the application configuration, but application tasks which + call the network functions should not use these events for other purposes. Initialization ============== @@ -52,92 +55,92 @@ Initialization Additional include files ------------------------ -The source file which declares the network configuration -structures and calls the network initialization function must include -.. code:: c +The source file which declares the network configuration structures and calls +the network initialization function must include + +.. code-block:: c #include Network Configuration --------------------- -The network configuration is specified by declaring -and initializing the ``rtems_bsdnet_config`` -structure. -.. code:: c +The network configuration is specified by declaring and initializing the +``rtems_bsdnet_config`` structure. + +.. code-block:: c struct rtems_bsdnet_config { - /* - * This entry points to the head of the ifconfig chain. - \*/ - struct rtems_bsdnet_ifconfig \*ifconfig; - /* - * This entry should be rtems_bsdnet_do_bootp if BOOTP - * is being used to configure the network, and NULL - * if BOOTP is not being used. - \*/ - void (\*bootp)(void); - /* - * The remaining items can be initialized to 0, in - * which case the default value will be used. - \*/ - rtems_task_priority network_task_priority; /* 100 \*/ - unsigned long mbuf_bytecount; /* 64 kbytes \*/ - unsigned long mbuf_cluster_bytecount; /* 128 kbytes \*/ - char \*hostname; /* BOOTP \*/ - char \*domainname; /* BOOTP \*/ - char \*gateway; /* BOOTP \*/ - char \*log_host; /* BOOTP \*/ - char \*name_server[3]; /* BOOTP \*/ - char \*ntp_server[3]; /* BOOTP \*/ - unsigned long sb_efficiency; /* 2 \*/ - /* UDP TX: 9216 bytes \*/ - unsigned long udp_tx_buf_size; - /* UDP RX: 40 * (1024 + sizeof(struct sockaddr_in)) \*/ - unsigned long udp_rx_buf_size; - /* TCP TX: 16 * 1024 bytes \*/ - unsigned long tcp_tx_buf_size; - /* TCP TX: 16 * 1024 bytes \*/ - unsigned long tcp_rx_buf_size; - /* Default Network Tasks CPU Affinity \*/ - #ifdef RTEMS_SMP - const cpu_set_t \*network_task_cpuset; - size_t network_task_cpuset_size; - #endif + /* + * This entry points to the head of the ifconfig chain. + */ + struct rtems_bsdnet_ifconfig *ifconfig; + /* + * This entry should be rtems_bsdnet_do_bootp if BOOTP + * is being used to configure the network, and NULL + * if BOOTP is not being used. + */ + void (*bootp)(void); + /* + * The remaining items can be initialized to 0, in + * which case the default value will be used. + */ + rtems_task_priority network_task_priority; /* 100 */ + unsigned long mbuf_bytecount; /* 64 kbytes */ + unsigned long mbuf_cluster_bytecount; /* 128 kbytes */ + char *hostname; /* BOOTP */ + char *domainname; /* BOOTP */ + char *gateway; /* BOOTP */ + char *log_host; /* BOOTP */ + char *name_server[3]; /* BOOTP */ + char *ntp_server[3]; /* BOOTP */ + unsigned long sb_efficiency; /* 2 */ + /* UDP TX: 9216 bytes */ + unsigned long udp_tx_buf_size; + /* UDP RX: 40 * (1024 + sizeof(struct sockaddr_in)) */ + unsigned long udp_rx_buf_size; + /* TCP TX: 16 * 1024 bytes */ + unsigned long tcp_tx_buf_size; + /* TCP TX: 16 * 1024 bytes */ + unsigned long tcp_rx_buf_size; + /* Default Network Tasks CPU Affinity */ + #ifdef RTEMS_SMP + const cpu_set_t *network_task_cpuset; + size_t network_task_cpuset_size; + #endif }; -The structure entries are described in the following table. -If your application uses BOOTP/DHCP to obtain network configuration -information and if you are happy with the default values described -below, you need to provide only the first two entries in this structure. - -``struct rtems_bsdnet_ifconfig \*ifconfig`` - - A pointer to the first configuration structure of the first network - device. This structure is described in the following section. - You must provide a value for this entry since there is no default value for it. - -``void (\*bootp)(void)`` - - This entry should be set to ``rtems_bsdnet_do_bootp`` if your - application by default uses the BOOTP/DHCP client protocol to obtain - network configuration information. It should be set to ``NULL`` if - your application does not use BOOTP/DHCP. - You can also use ``rtems_bsdnet_do_bootp_rootfs`` to have a set of - standard files created with the information return by the BOOTP/DHCP - protocol. The IP address is added to :file:`/etc/hosts` with the host - name and domain returned. If no host name or domain is returned``me.mydomain`` is used. The BOOTP/DHCP server's address is also - added to :file:`/etc/hosts`. The domain name server listed in the - BOOTP/DHCP information are added to :file:`/etc/resolv.conf`. A``search`` record is also added if a domain is returned. The files - are created if they do not exist. - The default ``rtems_bsdnet_do_bootp`` and``rtems_bsdnet_do_bootp_rootfs`` handlers will loop for-ever - waiting for a BOOTP/DHCP server to respond. If an error is detected - such as not valid interface or valid hardware address the target will - reboot allowing any hardware reset to correct itself. - You can provide your own custom handler which allows you to perform - an initialization that meets your specific system requirements. For - example you could try BOOTP/DHCP then enter a configuration tool if no - server is found allowing the user to switch to a static configuration. +The structure entries are described in the following table. If your +application uses BOOTP/DHCP to obtain network configuration information and if +you are happy with the default values described below, you need to provide only +the first two entries in this structure. + +``struct rtems_bsdnet_ifconfig *ifconfig`` + A pointer to the first configuration structure of the first network device. + This structure is described in the following section. You must provide a + value for this entry since there is no default value for it. + +``void (*bootp)(void)`` + This entry should be set to ``rtems_bsdnet_do_bootp`` if your application + by default uses the BOOTP/DHCP client protocol to obtain network + configuration information. It should be set to ``NULL`` if your + application does not use BOOTP/DHCP. You can also use + ``rtems_bsdnet_do_bootp_rootfs`` to have a set of standard files created + with the information return by the BOOTP/DHCP protocol. The IP address is + added to :file:`/etc/hosts` with the host name and domain returned. If no + host name or domain is returned ``me.mydomain`` is used. The BOOTP/DHCP + server's address is also added to :file:`/etc/hosts`. The domain name + server listed in the BOOTP/DHCP information are added to + :file:`/etc/resolv.conf`. A``search`` record is also added if a domain is + returned. The files are created if they do not exist. The default + ``rtems_bsdnet_do_bootp`` and ``rtems_bsdnet_do_bootp_rootfs`` handlers + will loop for-ever waiting for a BOOTP/DHCP server to respond. If an error + is detected such as not valid interface or valid hardware address the + target will reboot allowing any hardware reset to correct itself. You can + provide your own custom handler which allows you to perform an + initialization that meets your specific system requirements. For example + you could try BOOTP/DHCP then enter a configuration tool if no server is + found allowing the user to switch to a static configuration. ``int network_task_priority`` The priority at which the network task and network device @@ -152,95 +155,88 @@ below, you need to provide only the first two entries in this structure. The number of bytes to allocate from the heap for use as mbuf clusters. If a value of 0 is specified, 128 kbytes will be allocated. -``char \*hostname`` +``char *hostname`` The host name of the system. If this, or any of the following, entries are ``NULL`` the value may be obtained from a BOOTP/DHCP server. -``char \*domainname`` +``char *domainname`` The name of the Internet domain to which the system belongs. -``char \*gateway`` - The Internet host number of the network gateway machine, - specified in 'dotted decimal' (``129.128.4.1``) form. +``char *gateway`` + The Internet host number of the network gateway machine, specified in + 'dotted decimal' (``129.128.4.1``) form. -``char \*log_host`` - The Internet host number of the machine to which ``syslog`` messages - will be sent. +``char *log_host`` + The Internet host number of the machine to which ``syslog`` messages will + be sent. -``char \*name_server[3]`` - The Internet host numbers of up to three machines to be used as - Internet Domain Name Servers. +``char *name_server[3]`` + The Internet host numbers of up to three machines to be used as Internet + Domain Name Servers. -``char \*ntp_server[3]`` +``char *ntp_server[3]`` The Internet host numbers of up to three machines to be used as Network Time Protocol (NTP) Servers. ``unsigned long sb_efficiency`` - This is the first of five configuration parameters related to - the amount of memory each socket may consume for buffers. The - TCP/IP stack reserves buffers (e.g. mbufs) for each open socket. The - TCP/IP stack has different limits for the transmit and receive - buffers associated with each TCP and UDP socket. By tuning these - parameters, the application developer can make trade-offs between - memory consumption and performance. The default parameters favor - performance over memory consumption. Seehttp://www.rtems.org/ml/rtems-users/2004/february/msg00200.html - for more details but note that after the RTEMS 4.8 release series, - the sb_efficiency default was changed from ``8`` to ``2``. - The user should also be aware of the ``SO_SNDBUF`` and ``SO_RCVBUF`` - IO control operations. These can be used to specify the - send and receive buffer sizes for a specific socket. There - is no standard IO control to change the ``sb_efficiency`` factor. - The ``sb_efficiency`` parameter is a buffering factor used - in the implementation of the TCP/IP stack. The default is ``2`` - which indicates double buffering. When allocating memory for each + This is the first of five configuration parameters related to the amount of + memory each socket may consume for buffers. The TCP/IP stack reserves + buffers (e.g. mbufs) for each open socket. The TCP/IP stack has different + limits for the transmit and receive buffers associated with each TCP and + UDP socket. By tuning these parameters, the application developer can make + trade-offs between memory consumption and performance. The default + parameters favor performance over memory consumption. See + http://www.rtems.org/ml/rtems-users/2004/february/msg00200.html for more + details but note that after the RTEMS 4.8 release series, the + ``sb_efficiency`` default was changed from ``8`` to ``2``. The user should + also be aware of the ``SO_SNDBUF`` and ``SO_RCVBUF`` IO control operations. + These can be used to specify the send and receive buffer sizes for a + specific socket. There is no standard IO control to change the + ``sb_efficiency`` factor. The ``sb_efficiency`` parameter is a buffering + factor used in the implementation of the TCP/IP stack. The default is + ``2`` which indicates double buffering. When allocating memory for each socket, this number is multiplied by the buffer sizes for that socket. ``unsigned long udp_tx_buf_size`` - - This configuration parameter specifies the maximum amount of - buffer memory which may be used for UDP sockets to transmit - with. The default size is 9216 bytes which corresponds to - the maximum datagram size. + This configuration parameter specifies the maximum amount of buffer memory + which may be used for UDP sockets to transmit with. The default size is + 9216 bytes which corresponds to the maximum datagram size. ``unsigned long udp_rx_buf_size`` + This configuration parameter specifies the maximum amount of buffer memory + which may be used for UDP sockets to receive into. The default size is the + following length in bytes: - This configuration parameter specifies the maximum amount of - buffer memory which may be used for UDP sockets to receive - into. The default size is the following length in bytes: - - .. code:: c + .. code-block:: c 40 * (1024 + sizeof(struct sockaddr_in) ``unsigned long tcp_tx_buf_size`` - - This configuration parameter specifies the maximum amount of - buffer memory which may be used for TCP sockets to transmit - with. The default size is sixteen kilobytes. + This configuration parameter specifies the maximum amount of buffer memory + which may be used for TCP sockets to transmit with. The default size is + sixteen kilobytes. ``unsigned long tcp_rx_buf_size`` + This configuration parameter specifies the maximum amount of buffer memory + which may be used for TCP sockets to receive into. The default size is + sixteen kilobytes. - This configuration parameter specifies the maximum amount of - buffer memory which may be used for TCP sockets to receive - into. The default size is sixteen kilobytes. - -``const cpu_set_t \*network_task_cpuset`` - - This configuration parameter specifies the CPU affinity of the - network task. If set to ``0`` the network task can be scheduled on - any CPU. Only available in SMP configurations. +``const cpu_set_t *network_task_cpuset`` + This configuration parameter specifies the CPU affinity of the network + task. If set to ``0`` the network task can be scheduled on any CPU. Only + available in SMP configurations. ``size_t network_task_cpuset_size`` + This configuration parameter specifies the size of the + ``network_task_cpuset`` used. Only available in SMP configurations. - This configuration parameter specifies the size of the``network_task_cpuset`` used. Only available in SMP configurations. - -In addition, the following fields in the ``rtems_bsdnet_ifconfig`` -are of interest. +In addition, the following fields in the ``rtems_bsdnet_ifconfig`` are of +interest. *int port* - The I/O port number (ex: 0x240) on which the external Ethernet - can be accessed. + The I/O port number (ex: 0x240) on which the external Ethernet can be + accessed. *int irno* The interrupt number of the external Ethernet controller. @@ -251,133 +247,125 @@ are of interest. Network device configuration ---------------------------- -Network devices are specified and configured by declaring and initializing a``struct rtems_bsdnet_ifconfig`` structure for each network device. +Network devices are specified and configured by declaring and initializing a +``struct rtems_bsdnet_ifconfig`` structure for each network device. The structure entries are described in the following table. An application which uses a single network interface, gets network configuration information -from a BOOTP/DHCP server, and uses the default values for all driver -parameters needs to initialize only the first two entries in the -structure. - -``char \*name`` - The full name of the network device. This name consists of the - driver name and the unit number (e.g. ``"scc1"``). - The ``bsp.h`` include file usually defines RTEMS_BSP_NETWORK_DRIVER_NAME as - the name of the primary (or only) network driver. - -``int (\*attach)(struct rtems_bsdnet_ifconfig \*conf)`` - The address of the driver ``attach`` function. The network - initialization function calls this function to configure the driver and - attach it to the network stack. - The ``bsp.h`` include file usually defines RTEMS_BSP_NETWORK_DRIVER_ATTACH as - the name of the attach function of the primary (or only) network driver. - -``struct rtems_bsdnet_ifconfig \*next`` - A pointer to the network device configuration structure for the next network - interface, or ``NULL`` if this is the configuration structure of the - last network interface. - -``char \*ip_address`` - The Internet address of the device, - specified in 'dotted decimal' (``129.128.4.2``) form, or ``NULL`` - if the device configuration information is being obtained from a - BOOTP/DHCP server. - -``char \*ip_netmask`` - The Internet inetwork mask of the device, - specified in 'dotted decimal' (``255.255.255.0``) form, or ``NULL`` - if the device configuration information is being obtained from a - BOOTP/DHCP server. - -``void \*hardware_address`` - The hardware address of the device, or ``NULL`` if the driver is - to obtain the hardware address in some other way (usually by reading - it from the device or from the bootstrap ROM). +from a BOOTP/DHCP server, and uses the default values for all driver parameters +needs to initialize only the first two entries in the structure. + +``char *name`` + The full name of the network device. This name consists of the driver name + and the unit number (e.g. ``"scc1"``). The ``bsp.h`` include file usually + defines ``RTEMS_BSP_NETWORK_DRIVER_NAME`` as the name of the primary (or + only) network driver. + +``int (*attach)(struct rtems_bsdnet_ifconfig *conf)`` + + The address of the driver ``attach`` function. The network initialization + function calls this function to configure the driver and attach it to the + network stack. The ``bsp.h`` include file usually defines + ``RTEMS_BSP_NETWORK_DRIVER_ATTACH`` as the name of the attach function of + the primary (or only) network driver. + +``struct rtems_bsdnet_ifconfig *next`` + A pointer to the network device configuration structure for the next + network interface, or ``NULL`` if this is the configuration structure of + the last network interface. + +``char *ip_address`` + The Internet address of the device, specified in 'dotted decimal' + (``129.128.4.2``) form, or ``NULL`` if the device configuration information + is being obtained from a BOOTP/DHCP server. + +``char *ip_netmask`` + The Internet inetwork mask of the device, specified in 'dotted decimal' + (``255.255.255.0``) form, or ``NULL`` if the device configuration + information is being obtained from a BOOTP/DHCP server. + +``void *hardware_address`` + The hardware address of the device, or ``NULL`` if the driver is to obtain + the hardware address in some other way (usually by reading it from the + device or from the bootstrap ROM). ``int ignore_broadcast`` Zero if the device is to accept broadcast packets, non-zero if the device is to ignore broadcast packets. ``int mtu`` - The maximum transmission unit of the device, or zero if the driver - is to choose a default value (typically 1500 for Ethernet devices). + The maximum transmission unit of the device, or zero if the driver is to + choose a default value (typically 1500 for Ethernet devices). ``int rbuf_count`` - The number of receive buffers to use, or zero if the driver is to - choose a default value + The number of receive buffers to use, or zero if the driver is to choose a + default value ``int xbuf_count`` - The number of transmit buffers to use, or zero if the driver is to - choose a default value - Keep in mind that some network devices may use 4 or more + The number of transmit buffers to use, or zero if the driver is to choose a + default value Keep in mind that some network devices may use 4 or more transmit descriptors for a single transmit buffer. A complete network configuration specification can be as simple as the one -shown in the following example. -This configuration uses a single network interface, gets -network configuration information -from a BOOTP/DHCP server, and uses the default values for all driver -parameters. -.. code:: c +shown in the following example. This configuration uses a single network +interface, gets network configuration information from a BOOTP/DHCP server, and +uses the default values for all driver parameters. + +.. code-block:: c static struct rtems_bsdnet_ifconfig netdriver_config = { - RTEMS_BSP_NETWORK_DRIVER_NAME, - RTEMS_BSP_NETWORK_DRIVER_ATTACH + RTEMS_BSP_NETWORK_DRIVER_NAME, + RTEMS_BSP_NETWORK_DRIVER_ATTACH }; struct rtems_bsdnet_config rtems_bsdnet_config = { - &netdriver_config, - rtems_bsdnet_do_bootp, + &netdriver_config, + rtems_bsdnet_do_bootp, }; Network initialization ---------------------- -The networking tasks must be started before any network I/O operations -can be performed. This is done by calling: +The networking tasks must be started before any network I/O operations can be +performed. This is done by calling: -.. code:: c +.. code-block:: c rtems_bsdnet_initialize_network (); -This function is declared in ``rtems/rtems_bsdnet.h``. -t returns 0 on success and -1 on failure with an error code -in ``errno``. It is not possible to undo the effects of -a partial initialization, though, so the function can be -called only once irregardless of the return code. Consequently, -if the condition for the failure can be corrected, the -system must be reset to permit another network initialization -attempt. +This function is declared in ``rtems/rtems_bsdnet.h``. t returns 0 on success +and -1 on failure with an error code in ``errno``. It is not possible to undo +the effects of a partial initialization, though, so the function can be called +only once irregardless of the return code. Consequently, if the condition for +the failure can be corrected, the system must be reset to permit another +network initialization attempt. Application Programming Interface ================================= The RTEMS network package provides almost a complete set of BSD network -services. The network functions work like their BSD counterparts -with the following exceptions: +services. The network functions work like their BSD counterparts with the +following exceptions: - A given socket can be read or written by only one task at a time. -- The ``select`` function only works for file descriptors associated - with sockets. +- The ``select`` function only works for file descriptors associated with + sockets. - You must call ``openlog`` before calling any of the ``syslog`` functions. -- *Some of the network functions are not thread-safe.* - For example the following functions return a pointer to a static - buffer which remains valid only until the next call: +- *Some of the network functions are not thread-safe.* For example the + following functions return a pointer to a static buffer which remains valid + only until the next call: ``gethostbyaddr`` - ``gethostbyname`` - ``inet_ntoa`` - (``inet_ntop`` is thread-safe, though). - The RTEMS network package gathers statistics. -- Addition of a mechanism to "tap onto" an interface - and monitor every packet received and transmitted. +- Addition of a mechanism to "tap onto" an interface and monitor every packet + received and transmitted. - Addition of ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP`` socket options. @@ -387,9 +375,8 @@ sections. Network Statistics ------------------ -There are a number of functions to print statistics gathered by -the network stack. -These function are declared in ``rtems/rtems_bsdnet.h``. +There are a number of functions to print statistics gathered by the network +stack. These function are declared in ``rtems/rtems_bsdnet.h``. ``rtems_bsdnet_show_if_stats`` Display statistics gathered by network interfaces. @@ -415,442 +402,451 @@ These function are declared in ``rtems/rtems_bsdnet.h``. Tapping Into an Interface ------------------------- -RTEMS add two new ioctls to the BSD networking code: -SIOCSIFTAP and SIOCGIFTAP. These may be used to set and get a*tap function*. The tap function will be called for every -Ethernet packet received by the interface. +RTEMS add two new ioctls to the BSD networking code, ``SIOCSIFTAP`` and +``SIOCGIFTAP``. These may be used to set and get a *tap function*. The tap +function will be called for every Ethernet packet received by the interface. -These are called like other interface ioctls, such as SIOCSIFADDR. -When setting the tap function with SIOCSIFTAP, set the ifr_tap field -of the ifreq struct to the tap function. When retrieving the tap -function with SIOCGIFTAP, the current tap function will be returned in -the ifr_tap field. To stop tapping packets, call SIOCSIFTAP with a -ifr_tap field of 0. +These are called like other interface ioctls, such as ``SIOCSIFADDR``. When +setting the tap function with ``SIOCSIFTAP``, set the ifr_tap field of the +ifreq struct to the tap function. When retrieving the tap function with +``SIOCGIFTAP``, the current tap function will be returned in the ifr_tap field. +To stop tapping packets, call ``SIOCSIFTAP`` with a ``ifr_tap`` field of ``0``. The tap function is called like this: -.. code:: c - int tap (struct ifnet \*, struct ether_header \*, struct mbuf \*) +.. code-block:: c -The tap function should return 1 if the packet was fully handled, in -which case the caller will simply discard the mbuf. The tap function -should return 0 if the packet should be passed up to the higher -networking layers. + int tap (struct ifnet *, struct ether_header *, struct mbuf *) -The tap function is called with the network semaphore locked. It must -not make any calls on the application levels of the networking level -itself. It is safe to call other non-networking RTEMS functions. +The tap function should return ``1`` if the packet was fully handled, in which +case the caller will simply discard the mbuf. The tap function should return +``0`` if the packet should be passed up to the higher networking layers. + +The tap function is called with the network semaphore locked. It must not make +any calls on the application levels of the networking level itself. It is safe +to call other non-networking RTEMS functions. Socket Options -------------- -RTEMS adds two new ``SOL_SOCKET`` level options for ``setsockopt`` and``getsockopt``: ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP``. For both, the -option value should point to a sockwakeup structure. The sockwakeup -structure has the following fields: -.. code:: c +RTEMS adds two new ``SOL_SOCKET`` level options for ``setsockopt`` and +``getsockopt``: ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP``. For both, the option +value should point to a sockwakeup structure. The sockwakeup structure has the +following fields: + +.. code-block:: c - void (\*sw_pfn) (struct socket \*, caddr_t); + void (*sw_pfn) (struct socket *, caddr_t); caddr_t sw_arg; These options are used to set a callback function to be called when, for -example, there is -data available from the socket (``SO_RCVWAKEUP``) and when there is space -available to accept data written to the socket (``SO_SNDWAKEUP``). - -If ``setsockopt`` is called with the ``SO_RCVWAKEUP`` option, and the``sw_pfn`` field is not zero, then when there is data -available to be read from -the socket, the function pointed to by the ``sw_pfn`` field will be -called. A pointer to the socket structure will be passed as the first -argument to the function. The ``sw_arg`` field set by the``SO_RCVWAKEUP`` call will be passed as the second argument to the function. - -If ``setsockopt`` is called with the ``SO_SNDWAKEUP`` -function, and the ``sw_pfn`` field is not zero, then when -there is space available to accept data written to the socket, -the function pointed to by the ``sw_pfn`` field -will be called. The arguments passed to the function will be as with``SO_SNDWAKEUP``. - -When the function is called, the network semaphore will be locked and -the callback function runs in the context of the networking task. -The function must be careful not to call any networking functions. It -is OK to call an RTEMS function; for example, it is OK to send an -RTEMS event. +example, there is data available from the socket (``SO_RCVWAKEUP``) and when +there is space available to accept data written to the socket +(``SO_SNDWAKEUP``). + +If ``setsockopt`` is called with the ``SO_RCVWAKEUP`` option, and the +``sw_pfn`` field is not zero, then when there is data available to be read from +the socket, the function pointed to by the ``sw_pfn`` field will be called. A +pointer to the socket structure will be passed as the first argument to the +function. The ``sw_arg`` field set by the ``SO_RCVWAKEUP`` call will be passed +as the second argument to the function. + +If ``setsockopt`` is called with the ``SO_SNDWAKEUP`` function, and the +``sw_pfn`` field is not zero, then when there is space available to accept data +written to the socket, the function pointed to by the ``sw_pfn`` field will be +called. The arguments passed to the function will be as with ``SO_SNDWAKEUP``. + +When the function is called, the network semaphore will be locked and the +callback function runs in the context of the networking task. The function +must be careful not to call any networking functions. It is OK to call an +RTEMS function; for example, it is OK to send an RTEMS event. The purpose of these callback functions is to permit a more efficient -alternative to the select call when dealing with a large number of -sockets. - -The callbacks are called by the same criteria that the select -function uses for indicating "ready" sockets. In Stevens *Unix -Network Programming* on page 153-154 in the section "Under what Conditions -Is a Descriptor Ready?" you will find the definitive list of conditions -for readable and writable that also determine when the functions are -called. - -When the number of received bytes equals or exceeds the socket receive -buffer "low water mark" (default 1 byte) you get a readable callback. If -there are 100 bytes in the receive buffer and you only read 1, you will -not immediately get another callback. However, you will get another -callback after you read the remaining 99 bytes and at least 1 more byte -arrives. Using a non-blocking socket you should probably read until it -produces error EWOULDBLOCK and then allow the readable callback to tell -you when more data has arrived. (Condition 1.a.) - -For sending, when the socket is connected and the free space becomes at -or above the "low water mark" for the send buffer (default 4096 bytes) -you will receive a writable callback. You don't get continuous callbacks -if you don't write anything. Using a non-blocking write socket, you can -then call write until it returns a value less than the amount of data -requested to be sent or it produces error EWOULDBLOCK (indicating buffer -full and no longer writable). When this happens you can -try the write again, but it is often better to go do other things and -let the writable callback tell you when space is available to send -again. You only get a writable callback when the free space transitions -to above the "low water mark" and not every time you -write to a non-full send buffer. (Condition 2.a.) - -The remaining conditions enumerated by Stevens handle the fact that -sockets become readable and/or writable when connects, disconnects and -errors occur, not just when data is received or sent. For example, when -a server "listening" socket becomes readable it indicates that a client -has connected and accept can be called without blocking, not that -network data was received (Condition 1.c). +alternative to the select call when dealing with a large number of sockets. + +The callbacks are called by the same criteria that the select function uses for +indicating "ready" sockets. In Stevens *Unix Network Programming* on page +153-154 in the section "Under what Conditions Is a Descriptor Ready?" you will +find the definitive list of conditions for readable and writable that also +determine when the functions are called. + +When the number of received bytes equals or exceeds the socket receive buffer +"low water mark" (default 1 byte) you get a readable callback. If there are 100 +bytes in the receive buffer and you only read 1, you will not immediately get +another callback. However, you will get another callback after you read the +remaining 99 bytes and at least 1 more byte arrives. Using a non-blocking +socket you should probably read until it produces error ``EWOULDBLOCK`` and +then allow the readable callback to tell you when more data has arrived. +(Condition 1.a.) + +For sending, when the socket is connected and the free space becomes at or +above the "low water mark" for the send buffer (default 4096 bytes) you will +receive a writable callback. You don't get continuous callbacks if you don't +write anything. Using a non-blocking write socket, you can then call write +until it returns a value less than the amount of data requested to be sent or +it produces error ``EWOULDBLOCK`` (indicating buffer full and no longer +writable). When this happens you can try the write again, but it is often +better to go do other things and let the writable callback tell you when space +is available to send again. You only get a writable callback when the free +space transitions to above the "low water mark" and not every time you write to +a non-full send buffer. (Condition 2.a.) + +The remaining conditions enumerated by Stevens handle the fact that sockets +become readable and/or writable when connects, disconnects and errors occur, +not just when data is received or sent. For example, when a server "listening" +socket becomes readable it indicates that a client has connected and accept can +be called without blocking, not that network data was received (Condition 1.c). Adding an IP Alias ------------------ The following code snippet adds an IP alias: -.. code:: c - void addAlias(const char \*pName, const char \*pAddr, const char \*pMask) +.. code-block:: c + + void addAlias(const char *pName, const char *pAddr, const char *pMask) { - struct ifaliasreq aliasreq; - struct sockaddr_in \*in; - /* initialize alias request \*/ - memset(&aliasreq, 0, sizeof(aliasreq)); - sprintf(aliasreq.ifra_name, pName); - /* initialize alias address \*/ - in = (struct sockaddr_in \*)&aliasreq.ifra_addr; - in->sin_family = AF_INET; - in->sin_len = sizeof(aliasreq.ifra_addr); - in->sin_addr.s_addr = inet_addr(pAddr); - /* initialize alias mask \*/ - in = (struct sockaddr_in \*)&aliasreq.ifra_mask; - in->sin_family = AF_INET; - in->sin_len = sizeof(aliasreq.ifra_mask); - in->sin_addr.s_addr = inet_addr(pMask); - /* call to setup the alias \*/ - rtems_bsdnet_ifconfig(pName, SIOCAIFADDR, &aliasreq); + struct ifaliasreq aliasreq; + struct sockaddr_in *in; + + /* initialize alias request */ + memset(&aliasreq, 0, sizeof(aliasreq)); + sprintf(aliasreq.ifra_name, pName); + + /* initialize alias address */ + in = (struct sockaddr_in *)&aliasreq.ifra_addr; + in->sin_family = AF_INET; + in->sin_len = sizeof(aliasreq.ifra_addr); + in->sin_addr.s_addr = inet_addr(pAddr); + + /* initialize alias mask */ + in = (struct sockaddr_in *)&aliasreq.ifra_mask; + in->sin_family = AF_INET; + in->sin_len = sizeof(aliasreq.ifra_mask); + in->sin_addr.s_addr = inet_addr(pMask); + + /* call to setup the alias */ + rtems_bsdnet_ifconfig(pName, SIOCAIFADDR, &aliasreq); } -Thanks to `Mike Seirs `_ for this example -code. +Thanks to Mike Seirs for this example code. Adding a Default Route ---------------------- -The function provided in this section is functionally equivalent to -the command ``route add default gw yyy.yyy.yyy.yyy``: -.. code:: c +The function provided in this section is functionally equivalent to the command +``route add default gw yyy.yyy.yyy.yyy``: - void mon_ifconfig(int argc, char \*argv[], unsigned32 command_arg, - bool verbose) +.. code-block:: c + + void mon_ifconfig(int argc, char *argv[], unsigned32 command_arg, bool verbose) { - struct sockaddr_in ipaddr; - struct sockaddr_in dstaddr; - struct sockaddr_in netmask; - struct sockaddr_in broadcast; - char \*iface; - int f_ip = 0; - int f_ptp = 0; - int f_netmask = 0; - int f_up = 0; - int f_down = 0; - int f_bcast = 0; - int cur_idx; - int rc; - int flags; - bzero((void*) &ipaddr, sizeof(ipaddr)); - bzero((void*) &dstaddr, sizeof(dstaddr)); - bzero((void*) &netmask, sizeof(netmask)); - bzero((void*) &broadcast, sizeof(broadcast)); - ipaddr.sin_len = sizeof(ipaddr); - ipaddr.sin_family = AF_INET; - dstaddr.sin_len = sizeof(dstaddr); - dstaddr.sin_family = AF_INET; - netmask.sin_len = sizeof(netmask); - netmask.sin_family = AF_INET; - broadcast.sin_len = sizeof(broadcast); - broadcast.sin_family = AF_INET; - cur_idx = 0; - if (argc <= 1) { - /* display all interfaces \*/ - iface = NULL; - cur_idx += 1; - } else { - iface = argv[1]; - if (isdigit(\*argv[2])) { - if (inet_pton(AF_INET, argv[2], &ipaddr.sin_addr) < 0) { - printf("bad ip address: %s\\n", argv[2]); - return; - } - f_ip = 1; - cur_idx += 3; - } else { - cur_idx += 2; - } - } - if ((f_down !=0) && (f_ip != 0)) { - f_up = 1; - } - while(argc > cur_idx) { - if (strcmp(argv[cur_idx], "up") == 0) { - f_up = 1; - if (f_down != 0) { - printf("Can't make interface up and down\\n"); - } - } else if(strcmp(argv[cur_idx], "down") == 0) { - f_down = 1; - if (f_up != 0) { - printf("Can't make interface up and down\\n"); - } - } else if(strcmp(argv[cur_idx], "netmask") == 0) { - if ((cur_idx + 1) >= argc) { - printf("No netmask address\\n"); - return; - } - if (inet_pton(AF_INET, argv[cur_idx+1], &netmask.sin_addr) < 0) { - printf("bad netmask: %s\\n", argv[cur_idx]); - return; - } - f_netmask = 1; - cur_idx += 1; - } else if(strcmp(argv[cur_idx], "broadcast") == 0) { - if ((cur_idx + 1) >= argc) { - printf("No broadcast address\\n"); - return; - } - if (inet_pton(AF_INET, argv[cur_idx+1], &broadcast.sin_addr) < 0) { - printf("bad broadcast: %s\\n", argv[cur_idx]); - return; - } - f_bcast = 1; - cur_idx += 1; - } else if(strcmp(argv[cur_idx], "pointopoint") == 0) { - if ((cur_idx + 1) >= argc) { - printf("No pointopoint address\\n"); - return; - } - if (inet_pton(AF_INET, argv[cur_idx+1], &dstaddr.sin_addr) < 0) { - printf("bad pointopoint: %s\\n", argv[cur_idx]); - return; - } - f_ptp = 1; - cur_idx += 1; - } else { - printf("Bad parameter: %s\\n", argv[cur_idx]); - return; - } - cur_idx += 1; - } - printf("ifconfig "); - if (iface != NULL) { - printf("%s ", iface); - if (f_ip != 0) { - char str[256]; - inet_ntop(AF_INET, &ipaddr.sin_addr, str, 256); - printf("%s ", str); - } - if (f_netmask != 0) { - char str[256]; - inet_ntop(AF_INET, &netmask.sin_addr, str, 256); - printf("netmask %s ", str); - } - if (f_bcast != 0) { - char str[256]; - inet_ntop(AF_INET, &broadcast.sin_addr, str, 256); - printf("broadcast %s ", str); - } - if (f_ptp != 0) { - char str[256]; - inet_ntop(AF_INET, &dstaddr.sin_addr, str, 256); - printf("pointopoint %s ", str); - } - if (f_up != 0) { - printf("up\\n"); - } else if (f_down != 0) { - printf("down\\n"); - } else { - printf("\\n"); - } - } - if ((iface == NULL) \|| ((f_ip == 0) && (f_down == 0) && (f_up == 0))) { - rtems_bsdnet_show_if_stats(); - return; - } - flags = 0; - if (f_netmask) { - rc = rtems_bsdnet_ifconfig(iface, SIOCSIFNETMASK, &netmask); - if (rc < 0) { - printf("Could not set netmask: %s\\n", strerror(errno)); - return; - } - } - if (f_bcast) { - rc = rtems_bsdnet_ifconfig(iface, SIOCSIFBRDADDR, &broadcast); - if (rc < 0) { - printf("Could not set broadcast: %s\\n", strerror(errno)); - return; - } - } - if (f_ptp) { - rc = rtems_bsdnet_ifconfig(iface, SIOCSIFDSTADDR, &dstaddr); - if (rc < 0) { - printf("Could not set destination address: %s\\n", strerror(errno)); - return; - } - flags \|= IFF_POINTOPOINT; - } - /* This must come _after_ setting the netmask, broadcast addresses \*/ - if (f_ip) { - rc = rtems_bsdnet_ifconfig(iface, SIOCSIFADDR, &ipaddr); - if (rc < 0) { - printf("Could not set IP address: %s\\n", strerror(errno)); - return; - } - } - if (f_up != 0) { - flags \|= IFF_UP; - } - if (f_down != 0) { - printf("Warning: taking interfaces down is not supported\\n"); - } - rc = rtems_bsdnet_ifconfig(iface, SIOCSIFFLAGS, &flags); - if (rc < 0) { - printf("Could not set interface flags: %s\\n", strerror(errno)); - return; - } - } - void mon_route(int argc, char \*argv[], unsigned32 command_arg, - bool verbose) + struct sockaddr_in ipaddr; + struct sockaddr_in dstaddr; + struct sockaddr_in netmask; + struct sockaddr_in broadcast; + char *iface; + int f_ip = 0; + int f_ptp = 0; + int f_netmask = 0; + int f_up = 0; + int f_down = 0; + int f_bcast = 0; + int cur_idx; + int rc; + int flags; + + bzero((void*) &ipaddr, sizeof(ipaddr)); + bzero((void*) &dstaddr, sizeof(dstaddr)); + bzero((void*) &netmask, sizeof(netmask)); + bzero((void*) &broadcast, sizeof(broadcast)); + ipaddr.sin_len = sizeof(ipaddr); + ipaddr.sin_family = AF_INET; + dstaddr.sin_len = sizeof(dstaddr); + dstaddr.sin_family = AF_INET; + netmask.sin_len = sizeof(netmask); + netmask.sin_family = AF_INET; + broadcast.sin_len = sizeof(broadcast); + broadcast.sin_family = AF_INET; + cur_idx = 0; + + if (argc <= 1) { + /* display all interfaces */ + iface = NULL; + cur_idx += 1; + } else { + iface = argv[1]; + if (isdigit(*argv[2])) { + if (inet_pton(AF_INET, argv[2], &ipaddr.sin_addr) < 0) { + printf("bad ip address: %s\n", argv[2]); + return; + } + f_ip = 1; + cur_idx += 3; + } else { + cur_idx += 2; + } + } + + if ((f_down !=0) && (f_ip != 0)) { + f_up = 1; + } + + while(argc > cur_idx) { + if (strcmp(argv[cur_idx], "up") == 0) { + f_up = 1; + if (f_down != 0) { + printf("Can't make interface up and down\n"); + } + } else if(strcmp(argv[cur_idx], "down") == 0) { + f_down = 1; + if (f_up != 0) { + printf("Can't make interface up and down\n"); + } + } else if(strcmp(argv[cur_idx], "netmask") == 0) { + if ((cur_idx + 1) >= argc) { + printf("No netmask address\n"); + return; + } + if (inet_pton(AF_INET, argv[cur_idx+1], &netmask.sin_addr) < 0) { + printf("bad netmask: %s\n", argv[cur_idx]); + return; + } + f_netmask = 1; + cur_idx += 1; + } else if(strcmp(argv[cur_idx], "broadcast") == 0) { + if ((cur_idx + 1) >= argc) { + printf("No broadcast address\n"); + return; + } + if (inet_pton(AF_INET, argv[cur_idx+1], &broadcast.sin_addr) < 0) { + printf("bad broadcast: %s\n", argv[cur_idx]); + return; + } + f_bcast = 1; + cur_idx += 1; + } else if(strcmp(argv[cur_idx], "pointopoint") == 0) { + if ((cur_idx + 1) >= argc) { + printf("No pointopoint address\n"); + return; + } + if (inet_pton(AF_INET, argv[cur_idx+1], &dstaddr.sin_addr) < 0) { + printf("bad pointopoint: %s\n", argv[cur_idx]); + return; + } + f_ptp = 1; + cur_idx += 1; + } else { + printf("Bad parameter: %s\n", argv[cur_idx]); + return; + } + cur_idx += 1; + } + + printf("ifconfig "); + + if (iface != NULL) { + printf("%s ", iface); + if (f_ip != 0) { + char str[256]; + inet_ntop(AF_INET, &ipaddr.sin_addr, str, 256); + printf("%s ", str); + } + if (f_netmask != 0) { + char str[256]; + inet_ntop(AF_INET, &netmask.sin_addr, str, 256); + printf("netmask %s ", str); + } + if (f_bcast != 0) { + char str[256]; + inet_ntop(AF_INET, &broadcast.sin_addr, str, 256); + printf("broadcast %s ", str); + } + if (f_ptp != 0) { + char str[256]; + inet_ntop(AF_INET, &dstaddr.sin_addr, str, 256); + printf("pointopoint %s ", str); + } + if (f_up != 0) { + printf("up\n"); + } else if (f_down != 0) { + printf("down\n"); + } else { + printf("\n"); + } + } + + if ((iface == NULL) || ((f_ip == 0) && (f_down == 0) && (f_up == 0))) { + rtems_bsdnet_show_if_stats(); + return; + } + + flags = 0; + if (f_netmask) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFNETMASK, &netmask); + if (rc < 0) { + printf("Could not set netmask: %s\n", strerror(errno)); + return; + } + } + if (f_bcast) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFBRDADDR, &broadcast); + if (rc < 0) { + printf("Could not set broadcast: %s\n", strerror(errno)); + return; + } + } + if (f_ptp) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFDSTADDR, &dstaddr); + if (rc < 0) { + printf("Could not set destination address: %s\n", strerror(errno)); + return; + } + flags |= IFF_POINTOPOINT; + } + + /* This must come _after_ setting the netmask, broadcast addresses */ + if (f_ip) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFADDR, &ipaddr); + if (rc < 0) { + printf("Could not set IP address: %s\n", strerror(errno)); + return; + } + } + if (f_up != 0) { + flags |= IFF_UP; + } + if (f_down != 0) { + printf("Warning: taking interfaces down is not supported\n"); + } + + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFFLAGS, &flags); + if (rc < 0) { + printf("Could not set interface flags: %s\n", strerror(errno)); + return; + } + } + + void mon_route(int argc, char *argv[], unsigned32 command_arg, bool verbose) { - int cmd; - struct sockaddr_in dst; - struct sockaddr_in gw; - struct sockaddr_in netmask; - int f_host; - int f_gw = 0; - int cur_idx; - int flags; - int rc; - memset(&dst, 0, sizeof(dst)); - memset(&gw, 0, sizeof(gw)); - memset(&netmask, 0, sizeof(netmask)); - dst.sin_len = sizeof(dst); - dst.sin_family = AF_INET; - dst.sin_addr.s_addr = inet_addr("0.0.0.0"); - gw.sin_len = sizeof(gw); - gw.sin_family = AF_INET; - gw.sin_addr.s_addr = inet_addr("0.0.0.0"); - netmask.sin_len = sizeof(netmask); - netmask.sin_family = AF_INET; - netmask.sin_addr.s_addr = inet_addr("255.255.255.0"); - if (argc < 2) { - rtems_bsdnet_show_inet_routes(); - return; - } - if (strcmp(argv[1], "add") == 0) { - cmd = RTM_ADD; - } else if (strcmp(argv[1], "del") == 0) { - cmd = RTM_DELETE; - } else { - printf("invalid command: %s\\n", argv[1]); - printf("\\tit should be 'add' or 'del'\\n"); - return; - } - if (argc < 3) { - printf("not enough arguments\\n"); - return; - } - if (strcmp(argv[2], "-host") == 0) { - f_host = 1; - } else if (strcmp(argv[2], "-net") == 0) { - f_host = 0; - } else { - printf("Invalid type: %s\\n", argv[1]); - printf("\\tit should be '-host' or '-net'\\n"); - return; - } - if (argc < 4) { - printf("not enough arguments\\n"); - return; - } - inet_pton(AF_INET, argv[3], &dst.sin_addr); - cur_idx = 4; - while(cur_idx < argc) { - if (strcmp(argv[cur_idx], "gw") == 0) { - if ((cur_idx +1) >= argc) { - printf("no gateway address\\n"); - return; - } - f_gw = 1; - inet_pton(AF_INET, argv[cur_idx + 1], &gw.sin_addr); - cur_idx += 1; - } else if(strcmp(argv[cur_idx], "netmask") == 0) { - if ((cur_idx +1) >= argc) { - printf("no netmask address\\n"); - return; - } - f_gw = 1; - inet_pton(AF_INET, argv[cur_idx + 1], &netmask.sin_addr); - cur_idx += 1; - } else { - printf("Unknown argument\\n"); - return; - } - cur_idx += 1; - } - flags = RTF_STATIC; - if (f_gw != 0) { - flags \|= RTF_GATEWAY; - } - if (f_host != 0) { - flags \|= RTF_HOST; - } - rc = rtems_bsdnet_rtrequest(cmd, &dst, &gw, &netmask, flags, NULL); - if (rc < 0) { - printf("Error adding route\\n"); - } - } - -Thanks to `Jay Monkman `_ for this example + int cmd; + struct sockaddr_in dst; + struct sockaddr_in gw; + struct sockaddr_in netmask; + int f_host; + int f_gw = 0; + int cur_idx; + int flags; + int rc; + + memset(&dst, 0, sizeof(dst)); + memset(&gw, 0, sizeof(gw)); + memset(&netmask, 0, sizeof(netmask)); + dst.sin_len = sizeof(dst); + dst.sin_family = AF_INET; + dst.sin_addr.s_addr = inet_addr("0.0.0.0"); + gw.sin_len = sizeof(gw); + gw.sin_family = AF_INET; + gw.sin_addr.s_addr = inet_addr("0.0.0.0"); + netmask.sin_len = sizeof(netmask); + netmask.sin_family = AF_INET; + netmask.sin_addr.s_addr = inet_addr("255.255.255.0"); + + if (argc < 2) { + rtems_bsdnet_show_inet_routes(); + return; + } + + if (strcmp(argv[1], "add") == 0) { + cmd = RTM_ADD; + } else if (strcmp(argv[1], "del") == 0) { + cmd = RTM_DELETE; + } else { + printf("invalid command: %s\n", argv[1]); + printf("\tit should be 'add' or 'del'\n"); + return; + } + + if (argc < 3) { + printf("not enough arguments\n"); + return; + } + + if (strcmp(argv[2], "-host") == 0) { + f_host = 1; + } else if (strcmp(argv[2], "-net") == 0) { + f_host = 0; + } else { + printf("Invalid type: %s\n", argv[1]); + printf("\tit should be '-host' or '-net'\n"); + return; + } + + if (argc < 4) { + printf("not enough arguments\n"); + return; + } + + inet_pton(AF_INET, argv[3], &dst.sin_addr); + + cur_idx = 4; + while(cur_idx < argc) { + if (strcmp(argv[cur_idx], "gw") == 0) { + if ((cur_idx +1) >= argc) { + printf("no gateway address\n"); + return; + } + f_gw = 1; + inet_pton(AF_INET, argv[cur_idx + 1], &gw.sin_addr); + cur_idx += 1; + } else if(strcmp(argv[cur_idx], "netmask") == 0) { + if ((cur_idx +1) >= argc) { + printf("no netmask address\n"); + return; + } + f_gw = 1; + inet_pton(AF_INET, argv[cur_idx + 1], &netmask.sin_addr); + cur_idx += 1; + } else { + printf("Unknown argument\n"); + return; + } + cur_idx += 1; + } + + flags = RTF_STATIC; + if (f_gw != 0) { + flags |= RTF_GATEWAY; + } + if (f_host != 0) { + flags |= RTF_HOST; + } + + rc = rtems_bsdnet_rtrequest(cmd, &dst, &gw, &netmask, flags, NULL); + if (rc < 0) { + printf("Error adding route\n"); + } + } + +Thanks to Jay Monkman for this example code. Time Synchronization Using NTP ------------------------------ -.. code:: c +.. code-block:: c int rtems_bsdnet_synchronize_ntp (int interval, rtems_task_priority priority); -If the interval argument is 0 the routine synchronizes the RTEMS time-of-day -clock with the first NTP server in the rtems_bsdnet_ntpserve array and -returns. The priority argument is ignored. +If the interval argument is ``0`` the routine synchronizes the RTEMS +time-of-day clock with the first NTP server in the ``rtems_bsdnet_ntpserve`` +array and returns. The priority argument is ignored. -If the interval argument is greater than 0, the routine also starts an -RTEMS task at the specified priority and polls the NTP server every -'interval' seconds. NOTE: This mode of operation has not yet been -implemented. +If the interval argument is greater than 0, the routine also starts an RTEMS +task at the specified priority and polls the NTP server every 'interval' +seconds. NOTE: This mode of operation has not yet been implemented. On successful synchronization of the RTEMS time-of-day clock the routine -returns 0. If an error occurs a message is printed and the routine returns -1 -with an error code in errno. -There is no timeout - if there is no response from an NTP server the -routine will wait forever. - -.. COMMENT: Written by Eric Norum - -.. COMMENT: COPYRIGHT (c) 1988-2002. - -.. COMMENT: On-Line Applications Research Corporation (OAR). - -.. COMMENT: All rights reserved. - +returns ``0``. If an error occurs a message is printed and the routine returns +``-1`` with an error code in errno. There is no timeout - if there is no +response from an NTP server the routine will wait forever. -- cgit v1.2.3