1 | .. comment SPDX-License-Identifier: CC-BY-SA-4.0 |
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2 | |
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3 | .. COMMENT: Written by Eric Norum |
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4 | .. COMMENT: COPYRIGHT (c) 1988-2002. |
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5 | .. COMMENT: On-Line Applications Research Corporation (OAR). |
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6 | .. COMMENT: All rights reserved. |
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7 | |
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8 | Using Networking in an RTEMS Application |
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9 | ######################################## |
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10 | |
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11 | Makefile changes |
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12 | ================ |
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13 | |
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14 | Including the required managers |
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15 | ------------------------------- |
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16 | |
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17 | The FreeBSD networking code requires several RTEMS managers in the application: |
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18 | |
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19 | .. code-block:: c |
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20 | |
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21 | MANAGERS = io event semaphore |
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22 | |
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23 | Increasing the size of the heap |
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24 | ------------------------------- |
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25 | |
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26 | The networking tasks allocate a lot of memory. For most applications the heap |
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27 | should be at least 256 kbytes. The amount of memory set aside for the heap can |
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28 | be adjusted by setting the ``CFLAGS_LD`` definition as shown below: |
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29 | |
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30 | .. code-block:: c |
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31 | |
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32 | CFLAGS_LD += -Wl,--defsym -Wl,HeapSize=0x80000 |
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33 | |
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34 | This sets aside 512 kbytes of memory for the heap. |
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35 | |
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36 | System Configuration |
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37 | ==================== |
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38 | |
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39 | The networking tasks allocate some RTEMS objects. These must be accounted for |
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40 | in the application configuration table. The following lists the requirements. |
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41 | |
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42 | *TASKS* |
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43 | One network task plus a receive and transmit task for each device. |
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44 | |
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45 | *SEMAPHORES* |
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46 | One network semaphore plus one syslog mutex semaphore if the application |
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47 | uses openlog/syslog. |
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48 | |
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49 | *EVENTS* |
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50 | The network stack uses ``RTEMS_EVENT_24`` and ``RTEMS_EVENT_25``. This has |
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51 | no effect on the application configuration, but application tasks which |
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52 | call the network functions should not use these events for other purposes. |
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53 | |
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54 | Initialization |
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55 | ============== |
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56 | |
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57 | Additional include files |
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58 | ------------------------ |
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59 | |
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60 | The source file which declares the network configuration structures and calls |
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61 | the network initialization function must include |
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62 | |
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63 | .. code-block:: c |
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64 | |
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65 | #include <rtems/rtems_bsdnet.h> |
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66 | |
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67 | Network Configuration |
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68 | --------------------- |
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69 | |
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70 | The network configuration is specified by declaring and initializing the |
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71 | ``rtems_bsdnet_config`` structure. |
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72 | |
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73 | .. code-block:: c |
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74 | |
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75 | struct rtems_bsdnet_config { |
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76 | /* |
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77 | * This entry points to the head of the ifconfig chain. |
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78 | */ |
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79 | struct rtems_bsdnet_ifconfig *ifconfig; |
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80 | /* |
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81 | * This entry should be rtems_bsdnet_do_bootp if BOOTP |
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82 | * is being used to configure the network, and NULL |
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83 | * if BOOTP is not being used. |
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84 | */ |
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85 | void (*bootp)(void); |
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86 | /* |
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87 | * The remaining items can be initialized to 0, in |
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88 | * which case the default value will be used. |
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89 | */ |
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90 | rtems_task_priority network_task_priority; /* 100 */ |
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91 | unsigned long mbuf_bytecount; /* 64 kbytes */ |
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92 | unsigned long mbuf_cluster_bytecount; /* 128 kbytes */ |
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93 | char *hostname; /* BOOTP */ |
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94 | char *domainname; /* BOOTP */ |
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95 | char *gateway; /* BOOTP */ |
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96 | char *log_host; /* BOOTP */ |
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97 | char *name_server[3]; /* BOOTP */ |
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98 | char *ntp_server[3]; /* BOOTP */ |
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99 | unsigned long sb_efficiency; /* 2 */ |
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100 | /* UDP TX: 9216 bytes */ |
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101 | unsigned long udp_tx_buf_size; |
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102 | /* UDP RX: 40 * (1024 + sizeof(struct sockaddr_in)) */ |
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103 | unsigned long udp_rx_buf_size; |
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104 | /* TCP TX: 16 * 1024 bytes */ |
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105 | unsigned long tcp_tx_buf_size; |
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106 | /* TCP TX: 16 * 1024 bytes */ |
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107 | unsigned long tcp_rx_buf_size; |
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108 | /* Default Network Tasks CPU Affinity */ |
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109 | #ifdef RTEMS_SMP |
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110 | const cpu_set_t *network_task_cpuset; |
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111 | size_t network_task_cpuset_size; |
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112 | #endif |
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113 | }; |
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114 | |
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115 | The structure entries are described in the following table. If your |
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116 | application uses BOOTP/DHCP to obtain network configuration information and if |
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117 | you are happy with the default values described below, you need to provide only |
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118 | the first two entries in this structure. |
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119 | |
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120 | ``struct rtems_bsdnet_ifconfig *ifconfig`` |
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121 | A pointer to the first configuration structure of the first network device. |
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122 | This structure is described in the following section. You must provide a |
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123 | value for this entry since there is no default value for it. |
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124 | |
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125 | ``void (*bootp)(void)`` |
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126 | This entry should be set to ``rtems_bsdnet_do_bootp`` if your application |
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127 | by default uses the BOOTP/DHCP client protocol to obtain network |
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128 | configuration information. It should be set to ``NULL`` if your |
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129 | application does not use BOOTP/DHCP. You can also use |
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130 | ``rtems_bsdnet_do_bootp_rootfs`` to have a set of standard files created |
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131 | with the information return by the BOOTP/DHCP protocol. The IP address is |
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132 | added to :file:`/etc/hosts` with the host name and domain returned. If no |
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133 | host name or domain is returned ``me.mydomain`` is used. The BOOTP/DHCP |
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134 | server's address is also added to :file:`/etc/hosts`. The domain name |
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135 | server listed in the BOOTP/DHCP information are added to |
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136 | :file:`/etc/resolv.conf`. A``search`` record is also added if a domain is |
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137 | returned. The files are created if they do not exist. The default |
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138 | ``rtems_bsdnet_do_bootp`` and ``rtems_bsdnet_do_bootp_rootfs`` handlers |
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139 | will loop for-ever waiting for a BOOTP/DHCP server to respond. If an error |
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140 | is detected such as not valid interface or valid hardware address the |
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141 | target will reboot allowing any hardware reset to correct itself. You can |
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142 | provide your own custom handler which allows you to perform an |
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143 | initialization that meets your specific system requirements. For example |
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144 | you could try BOOTP/DHCP then enter a configuration tool if no server is |
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145 | found allowing the user to switch to a static configuration. |
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146 | |
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147 | ``int network_task_priority`` |
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148 | The priority at which the network task and network device |
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149 | receive and transmit tasks will run. |
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150 | If a value of 0 is specified the tasks will run at priority 100. |
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151 | |
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152 | ``unsigned long mbuf_bytecount`` |
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153 | The number of bytes to allocate from the heap for use as mbufs. |
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154 | If a value of 0 is specified, 64 kbytes will be allocated. |
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155 | |
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156 | ``unsigned long mbuf_cluster_bytecount`` |
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157 | The number of bytes to allocate from the heap for use as mbuf clusters. |
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158 | If a value of 0 is specified, 128 kbytes will be allocated. |
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159 | |
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160 | ``char *hostname`` |
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161 | The host name of the system. |
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162 | If this, or any of the following, entries are ``NULL`` the value |
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163 | may be obtained from a BOOTP/DHCP server. |
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164 | |
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165 | ``char *domainname`` |
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166 | The name of the Internet domain to which the system belongs. |
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167 | |
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168 | ``char *gateway`` |
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169 | The Internet host number of the network gateway machine, specified in |
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170 | 'dotted decimal' (``129.128.4.1``) form. |
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171 | |
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172 | ``char *log_host`` |
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173 | The Internet host number of the machine to which ``syslog`` messages will |
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174 | be sent. |
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175 | |
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176 | ``char *name_server[3]`` |
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177 | The Internet host numbers of up to three machines to be used as Internet |
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178 | Domain Name Servers. |
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179 | |
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180 | ``char *ntp_server[3]`` |
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181 | The Internet host numbers of up to three machines to be used as |
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182 | Network Time Protocol (NTP) Servers. |
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183 | |
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184 | ``unsigned long sb_efficiency`` |
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185 | This is the first of five configuration parameters related to the amount of |
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186 | memory each socket may consume for buffers. The TCP/IP stack reserves |
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187 | buffers (e.g. mbufs) for each open socket. The TCP/IP stack has different |
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188 | limits for the transmit and receive buffers associated with each TCP and |
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189 | UDP socket. By tuning these parameters, the application developer can make |
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190 | trade-offs between memory consumption and performance. The default |
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191 | parameters favor performance over memory consumption. See |
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192 | http://www.rtems.org/ml/rtems-users/2004/february/msg00200.html for more |
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193 | details but note that after the RTEMS 4.8 release series, the |
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194 | ``sb_efficiency`` default was changed from ``8`` to ``2``. The user should |
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195 | also be aware of the ``SO_SNDBUF`` and ``SO_RCVBUF`` IO control operations. |
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196 | These can be used to specify the send and receive buffer sizes for a |
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197 | specific socket. There is no standard IO control to change the |
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198 | ``sb_efficiency`` factor. The ``sb_efficiency`` parameter is a buffering |
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199 | factor used in the implementation of the TCP/IP stack. The default is |
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200 | ``2`` which indicates double buffering. When allocating memory for each |
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201 | socket, this number is multiplied by the buffer sizes for that socket. |
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202 | |
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203 | ``unsigned long udp_tx_buf_size`` |
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204 | This configuration parameter specifies the maximum amount of buffer memory |
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205 | which may be used for UDP sockets to transmit with. The default size is |
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206 | 9216 bytes which corresponds to the maximum datagram size. |
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207 | |
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208 | ``unsigned long udp_rx_buf_size`` |
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209 | This configuration parameter specifies the maximum amount of buffer memory |
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210 | which may be used for UDP sockets to receive into. The default size is the |
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211 | following length in bytes: |
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212 | |
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213 | .. code-block:: c |
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214 | |
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215 | 40 * (1024 + sizeof(struct sockaddr_in) |
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216 | |
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217 | ``unsigned long tcp_tx_buf_size`` |
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218 | This configuration parameter specifies the maximum amount of buffer memory |
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219 | which may be used for TCP sockets to transmit with. The default size is |
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220 | sixteen kilobytes. |
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221 | |
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222 | ``unsigned long tcp_rx_buf_size`` |
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223 | This configuration parameter specifies the maximum amount of buffer memory |
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224 | which may be used for TCP sockets to receive into. The default size is |
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225 | sixteen kilobytes. |
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226 | |
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227 | ``const cpu_set_t *network_task_cpuset`` |
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228 | This configuration parameter specifies the CPU affinity of the network |
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229 | task. If set to ``0`` the network task can be scheduled on any CPU. Only |
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230 | available in SMP configurations. |
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231 | |
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232 | ``size_t network_task_cpuset_size`` |
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233 | This configuration parameter specifies the size of the |
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234 | ``network_task_cpuset`` used. Only available in SMP configurations. |
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235 | |
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236 | In addition, the following fields in the ``rtems_bsdnet_ifconfig`` are of |
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237 | interest. |
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238 | |
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239 | *int port* |
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240 | The I/O port number (ex: 0x240) on which the external Ethernet can be |
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241 | accessed. |
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242 | |
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243 | *int irno* |
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244 | The interrupt number of the external Ethernet controller. |
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245 | |
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246 | *int bpar* |
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247 | The address of the shared memory on the external Ethernet controller. |
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248 | |
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249 | Network device configuration |
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250 | ---------------------------- |
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251 | |
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252 | Network devices are specified and configured by declaring and initializing a |
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253 | ``struct rtems_bsdnet_ifconfig`` structure for each network device. |
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254 | |
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255 | The structure entries are described in the following table. An application |
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256 | which uses a single network interface, gets network configuration information |
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257 | from a BOOTP/DHCP server, and uses the default values for all driver parameters |
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258 | needs to initialize only the first two entries in the structure. |
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259 | |
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260 | ``char *name`` |
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261 | The full name of the network device. This name consists of the driver name |
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262 | and the unit number (e.g. ``"scc1"``). The ``bsp.h`` include file usually |
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263 | defines ``RTEMS_BSP_NETWORK_DRIVER_NAME`` as the name of the primary (or |
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264 | only) network driver. |
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265 | |
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266 | ``int (*attach)(struct rtems_bsdnet_ifconfig *conf)`` |
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267 | |
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268 | The address of the driver ``attach`` function. The network initialization |
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269 | function calls this function to configure the driver and attach it to the |
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270 | network stack. The ``bsp.h`` include file usually defines |
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271 | ``RTEMS_BSP_NETWORK_DRIVER_ATTACH`` as the name of the attach function of |
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272 | the primary (or only) network driver. |
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273 | |
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274 | ``struct rtems_bsdnet_ifconfig *next`` |
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275 | A pointer to the network device configuration structure for the next |
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276 | network interface, or ``NULL`` if this is the configuration structure of |
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277 | the last network interface. |
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278 | |
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279 | ``char *ip_address`` |
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280 | The Internet address of the device, specified in 'dotted decimal' |
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281 | (``129.128.4.2``) form, or ``NULL`` if the device configuration information |
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282 | is being obtained from a BOOTP/DHCP server. |
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283 | |
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284 | ``char *ip_netmask`` |
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285 | The Internet inetwork mask of the device, specified in 'dotted decimal' |
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286 | (``255.255.255.0``) form, or ``NULL`` if the device configuration |
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287 | information is being obtained from a BOOTP/DHCP server. |
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288 | |
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289 | ``void *hardware_address`` |
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290 | The hardware address of the device, or ``NULL`` if the driver is to obtain |
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291 | the hardware address in some other way (usually by reading it from the |
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292 | device or from the bootstrap ROM). |
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293 | |
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294 | ``int ignore_broadcast`` |
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295 | Zero if the device is to accept broadcast packets, non-zero if the device |
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296 | is to ignore broadcast packets. |
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297 | |
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298 | ``int mtu`` |
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299 | The maximum transmission unit of the device, or zero if the driver is to |
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300 | choose a default value (typically 1500 for Ethernet devices). |
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301 | |
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302 | ``int rbuf_count`` |
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303 | The number of receive buffers to use, or zero if the driver is to choose a |
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304 | default value |
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305 | |
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306 | ``int xbuf_count`` |
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307 | The number of transmit buffers to use, or zero if the driver is to choose a |
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308 | default value Keep in mind that some network devices may use 4 or more |
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309 | transmit descriptors for a single transmit buffer. |
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310 | |
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311 | A complete network configuration specification can be as simple as the one |
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312 | shown in the following example. This configuration uses a single network |
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313 | interface, gets network configuration information from a BOOTP/DHCP server, and |
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314 | uses the default values for all driver parameters. |
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315 | |
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316 | .. code-block:: c |
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317 | |
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318 | static struct rtems_bsdnet_ifconfig netdriver_config = { |
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319 | RTEMS_BSP_NETWORK_DRIVER_NAME, |
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320 | RTEMS_BSP_NETWORK_DRIVER_ATTACH |
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321 | }; |
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322 | struct rtems_bsdnet_config rtems_bsdnet_config = { |
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323 | &netdriver_config, |
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324 | rtems_bsdnet_do_bootp, |
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325 | }; |
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326 | |
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327 | Network initialization |
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328 | ---------------------- |
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329 | |
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330 | The networking tasks must be started before any network I/O operations can be |
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331 | performed. This is done by calling: |
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332 | |
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333 | .. code-block:: c |
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334 | |
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335 | rtems_bsdnet_initialize_network (); |
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336 | |
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337 | This function is declared in ``rtems/rtems_bsdnet.h``. t returns 0 on success |
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338 | and -1 on failure with an error code in ``errno``. It is not possible to undo |
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339 | the effects of a partial initialization, though, so the function can be called |
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340 | only once irregardless of the return code. Consequently, if the condition for |
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341 | the failure can be corrected, the system must be reset to permit another |
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342 | network initialization attempt. |
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343 | |
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344 | Application Programming Interface |
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345 | ================================= |
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346 | |
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347 | The RTEMS network package provides almost a complete set of BSD network |
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348 | services. The network functions work like their BSD counterparts with the |
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349 | following exceptions: |
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350 | |
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351 | - A given socket can be read or written by only one task at a time. |
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352 | |
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353 | - The ``select`` function only works for file descriptors associated with |
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354 | sockets. |
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355 | |
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356 | - You must call ``openlog`` before calling any of the ``syslog`` functions. |
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357 | |
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358 | - *Some of the network functions are not thread-safe.* For example the |
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359 | following functions return a pointer to a static buffer which remains valid |
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360 | only until the next call: |
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361 | |
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362 | ``gethostbyaddr`` |
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363 | ``gethostbyname`` |
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364 | ``inet_ntoa`` (``inet_ntop`` is thread-safe, though). |
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365 | |
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366 | - The RTEMS network package gathers statistics. |
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367 | |
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368 | - Addition of a mechanism to "tap onto" an interface and monitor every packet |
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369 | received and transmitted. |
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370 | |
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371 | - Addition of ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP`` socket options. |
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372 | |
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373 | Some of the new features are discussed in more detail in the following |
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374 | sections. |
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375 | |
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376 | Network Statistics |
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377 | ------------------ |
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378 | |
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379 | There are a number of functions to print statistics gathered by the network |
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380 | stack. These function are declared in ``rtems/rtems_bsdnet.h``. |
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381 | |
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382 | ``rtems_bsdnet_show_if_stats`` |
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383 | Display statistics gathered by network interfaces. |
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384 | |
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385 | ``rtems_bsdnet_show_ip_stats`` |
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386 | Display IP packet statistics. |
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387 | |
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388 | ``rtems_bsdnet_show_icmp_stats`` |
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389 | Display ICMP packet statistics. |
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390 | |
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391 | ``rtems_bsdnet_show_tcp_stats`` |
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392 | Display TCP packet statistics. |
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393 | |
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394 | ``rtems_bsdnet_show_udp_stats`` |
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395 | Display UDP packet statistics. |
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396 | |
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397 | ``rtems_bsdnet_show_mbuf_stats`` |
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398 | Display mbuf statistics. |
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399 | |
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400 | ``rtems_bsdnet_show_inet_routes`` |
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401 | Display the routing table. |
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402 | |
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403 | Tapping Into an Interface |
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404 | ------------------------- |
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405 | |
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406 | RTEMS add two new ioctls to the BSD networking code, ``SIOCSIFTAP`` and |
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407 | ``SIOCGIFTAP``. These may be used to set and get a *tap function*. The tap |
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408 | function will be called for every Ethernet packet received by the interface. |
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409 | |
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410 | These are called like other interface ioctls, such as ``SIOCSIFADDR``. When |
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411 | setting the tap function with ``SIOCSIFTAP``, set the ifr_tap field of the |
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412 | ifreq struct to the tap function. When retrieving the tap function with |
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413 | ``SIOCGIFTAP``, the current tap function will be returned in the ifr_tap field. |
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414 | To stop tapping packets, call ``SIOCSIFTAP`` with a ``ifr_tap`` field of ``0``. |
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415 | |
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416 | The tap function is called like this: |
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417 | |
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418 | .. code-block:: c |
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419 | |
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420 | int tap (struct ifnet *, struct ether_header *, struct mbuf *) |
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421 | |
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422 | The tap function should return ``1`` if the packet was fully handled, in which |
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423 | case the caller will simply discard the mbuf. The tap function should return |
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424 | ``0`` if the packet should be passed up to the higher networking layers. |
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425 | |
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426 | The tap function is called with the network semaphore locked. It must not make |
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427 | any calls on the application levels of the networking level itself. It is safe |
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428 | to call other non-networking RTEMS functions. |
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429 | |
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430 | Socket Options |
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431 | -------------- |
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432 | |
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433 | RTEMS adds two new ``SOL_SOCKET`` level options for ``setsockopt`` and |
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434 | ``getsockopt``: ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP``. For both, the option |
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435 | value should point to a sockwakeup structure. The sockwakeup structure has the |
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436 | following fields: |
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437 | |
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438 | .. code-block:: c |
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439 | |
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440 | void (*sw_pfn) (struct socket *, caddr_t); |
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441 | caddr_t sw_arg; |
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442 | |
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443 | These options are used to set a callback function to be called when, for |
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444 | example, there is data available from the socket (``SO_RCVWAKEUP``) and when |
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445 | there is space available to accept data written to the socket |
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446 | (``SO_SNDWAKEUP``). |
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447 | |
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448 | If ``setsockopt`` is called with the ``SO_RCVWAKEUP`` option, and the |
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449 | ``sw_pfn`` field is not zero, then when there is data available to be read from |
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450 | the socket, the function pointed to by the ``sw_pfn`` field will be called. A |
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451 | pointer to the socket structure will be passed as the first argument to the |
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452 | function. The ``sw_arg`` field set by the ``SO_RCVWAKEUP`` call will be passed |
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453 | as the second argument to the function. |
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454 | |
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455 | If ``setsockopt`` is called with the ``SO_SNDWAKEUP`` function, and the |
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456 | ``sw_pfn`` field is not zero, then when there is space available to accept data |
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457 | written to the socket, the function pointed to by the ``sw_pfn`` field will be |
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458 | called. The arguments passed to the function will be as with ``SO_SNDWAKEUP``. |
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459 | |
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460 | When the function is called, the network semaphore will be locked and the |
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461 | callback function runs in the context of the networking task. The function |
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462 | must be careful not to call any networking functions. It is OK to call an |
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463 | RTEMS function; for example, it is OK to send an RTEMS event. |
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464 | |
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465 | The purpose of these callback functions is to permit a more efficient |
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466 | alternative to the select call when dealing with a large number of sockets. |
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467 | |
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468 | The callbacks are called by the same criteria that the select function uses for |
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469 | indicating "ready" sockets. In Stevens *Unix Network Programming* on page |
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470 | 153-154 in the section "Under what Conditions Is a Descriptor Ready?" you will |
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471 | find the definitive list of conditions for readable and writable that also |
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472 | determine when the functions are called. |
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473 | |
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474 | When the number of received bytes equals or exceeds the socket receive buffer |
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475 | "low water mark" (default 1 byte) you get a readable callback. If there are 100 |
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476 | bytes in the receive buffer and you only read 1, you will not immediately get |
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477 | another callback. However, you will get another callback after you read the |
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478 | remaining 99 bytes and at least 1 more byte arrives. Using a non-blocking |
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479 | socket you should probably read until it produces error ``EWOULDBLOCK`` and |
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480 | then allow the readable callback to tell you when more data has arrived. |
---|
481 | (Condition 1.a.) |
---|
482 | |
---|
483 | For sending, when the socket is connected and the free space becomes at or |
---|
484 | above the "low water mark" for the send buffer (default 4096 bytes) you will |
---|
485 | receive a writable callback. You don't get continuous callbacks if you don't |
---|
486 | write anything. Using a non-blocking write socket, you can then call write |
---|
487 | until it returns a value less than the amount of data requested to be sent or |
---|
488 | it produces error ``EWOULDBLOCK`` (indicating buffer full and no longer |
---|
489 | writable). When this happens you can try the write again, but it is often |
---|
490 | better to go do other things and let the writable callback tell you when space |
---|
491 | is available to send again. You only get a writable callback when the free |
---|
492 | space transitions to above the "low water mark" and not every time you write to |
---|
493 | a non-full send buffer. (Condition 2.a.) |
---|
494 | |
---|
495 | The remaining conditions enumerated by Stevens handle the fact that sockets |
---|
496 | become readable and/or writable when connects, disconnects and errors occur, |
---|
497 | not just when data is received or sent. For example, when a server "listening" |
---|
498 | socket becomes readable it indicates that a client has connected and accept can |
---|
499 | be called without blocking, not that network data was received (Condition 1.c). |
---|
500 | |
---|
501 | Adding an IP Alias |
---|
502 | ------------------ |
---|
503 | |
---|
504 | The following code snippet adds an IP alias: |
---|
505 | |
---|
506 | .. code-block:: c |
---|
507 | |
---|
508 | void addAlias(const char *pName, const char *pAddr, const char *pMask) |
---|
509 | { |
---|
510 | struct ifaliasreq aliasreq; |
---|
511 | struct sockaddr_in *in; |
---|
512 | |
---|
513 | /* initialize alias request */ |
---|
514 | memset(&aliasreq, 0, sizeof(aliasreq)); |
---|
515 | sprintf(aliasreq.ifra_name, pName); |
---|
516 | |
---|
517 | /* initialize alias address */ |
---|
518 | in = (struct sockaddr_in *)&aliasreq.ifra_addr; |
---|
519 | in->sin_family = AF_INET; |
---|
520 | in->sin_len = sizeof(aliasreq.ifra_addr); |
---|
521 | in->sin_addr.s_addr = inet_addr(pAddr); |
---|
522 | |
---|
523 | /* initialize alias mask */ |
---|
524 | in = (struct sockaddr_in *)&aliasreq.ifra_mask; |
---|
525 | in->sin_family = AF_INET; |
---|
526 | in->sin_len = sizeof(aliasreq.ifra_mask); |
---|
527 | in->sin_addr.s_addr = inet_addr(pMask); |
---|
528 | |
---|
529 | /* call to setup the alias */ |
---|
530 | rtems_bsdnet_ifconfig(pName, SIOCAIFADDR, &aliasreq); |
---|
531 | } |
---|
532 | |
---|
533 | Thanks to Mike Seirs <mailto:mikes@poliac.com> for this example code. |
---|
534 | |
---|
535 | Adding a Default Route |
---|
536 | ---------------------- |
---|
537 | |
---|
538 | The function provided in this section is functionally equivalent to the command |
---|
539 | ``route add default gw yyy.yyy.yyy.yyy``: |
---|
540 | |
---|
541 | .. code-block:: c |
---|
542 | |
---|
543 | void mon_ifconfig(int argc, char *argv[], unsigned32 command_arg, bool verbose) |
---|
544 | { |
---|
545 | struct sockaddr_in ipaddr; |
---|
546 | struct sockaddr_in dstaddr; |
---|
547 | struct sockaddr_in netmask; |
---|
548 | struct sockaddr_in broadcast; |
---|
549 | char *iface; |
---|
550 | int f_ip = 0; |
---|
551 | int f_ptp = 0; |
---|
552 | int f_netmask = 0; |
---|
553 | int f_up = 0; |
---|
554 | int f_down = 0; |
---|
555 | int f_bcast = 0; |
---|
556 | int cur_idx; |
---|
557 | int rc; |
---|
558 | int flags; |
---|
559 | |
---|
560 | bzero((void*) &ipaddr, sizeof(ipaddr)); |
---|
561 | bzero((void*) &dstaddr, sizeof(dstaddr)); |
---|
562 | bzero((void*) &netmask, sizeof(netmask)); |
---|
563 | bzero((void*) &broadcast, sizeof(broadcast)); |
---|
564 | ipaddr.sin_len = sizeof(ipaddr); |
---|
565 | ipaddr.sin_family = AF_INET; |
---|
566 | dstaddr.sin_len = sizeof(dstaddr); |
---|
567 | dstaddr.sin_family = AF_INET; |
---|
568 | netmask.sin_len = sizeof(netmask); |
---|
569 | netmask.sin_family = AF_INET; |
---|
570 | broadcast.sin_len = sizeof(broadcast); |
---|
571 | broadcast.sin_family = AF_INET; |
---|
572 | cur_idx = 0; |
---|
573 | |
---|
574 | if (argc <= 1) { |
---|
575 | /* display all interfaces */ |
---|
576 | iface = NULL; |
---|
577 | cur_idx += 1; |
---|
578 | } else { |
---|
579 | iface = argv[1]; |
---|
580 | if (isdigit(*argv[2])) { |
---|
581 | if (inet_pton(AF_INET, argv[2], &ipaddr.sin_addr) < 0) { |
---|
582 | printf("bad ip address: %s\n", argv[2]); |
---|
583 | return; |
---|
584 | } |
---|
585 | f_ip = 1; |
---|
586 | cur_idx += 3; |
---|
587 | } else { |
---|
588 | cur_idx += 2; |
---|
589 | } |
---|
590 | } |
---|
591 | |
---|
592 | if ((f_down !=0) && (f_ip != 0)) { |
---|
593 | f_up = 1; |
---|
594 | } |
---|
595 | |
---|
596 | while(argc > cur_idx) { |
---|
597 | if (strcmp(argv[cur_idx], "up") == 0) { |
---|
598 | f_up = 1; |
---|
599 | if (f_down != 0) { |
---|
600 | printf("Can't make interface up and down\n"); |
---|
601 | } |
---|
602 | } else if(strcmp(argv[cur_idx], "down") == 0) { |
---|
603 | f_down = 1; |
---|
604 | if (f_up != 0) { |
---|
605 | printf("Can't make interface up and down\n"); |
---|
606 | } |
---|
607 | } else if(strcmp(argv[cur_idx], "netmask") == 0) { |
---|
608 | if ((cur_idx + 1) >= argc) { |
---|
609 | printf("No netmask address\n"); |
---|
610 | return; |
---|
611 | } |
---|
612 | if (inet_pton(AF_INET, argv[cur_idx+1], &netmask.sin_addr) < 0) { |
---|
613 | printf("bad netmask: %s\n", argv[cur_idx]); |
---|
614 | return; |
---|
615 | } |
---|
616 | f_netmask = 1; |
---|
617 | cur_idx += 1; |
---|
618 | } else if(strcmp(argv[cur_idx], "broadcast") == 0) { |
---|
619 | if ((cur_idx + 1) >= argc) { |
---|
620 | printf("No broadcast address\n"); |
---|
621 | return; |
---|
622 | } |
---|
623 | if (inet_pton(AF_INET, argv[cur_idx+1], &broadcast.sin_addr) < 0) { |
---|
624 | printf("bad broadcast: %s\n", argv[cur_idx]); |
---|
625 | return; |
---|
626 | } |
---|
627 | f_bcast = 1; |
---|
628 | cur_idx += 1; |
---|
629 | } else if(strcmp(argv[cur_idx], "pointopoint") == 0) { |
---|
630 | if ((cur_idx + 1) >= argc) { |
---|
631 | printf("No pointopoint address\n"); |
---|
632 | return; |
---|
633 | } |
---|
634 | if (inet_pton(AF_INET, argv[cur_idx+1], &dstaddr.sin_addr) < 0) { |
---|
635 | printf("bad pointopoint: %s\n", argv[cur_idx]); |
---|
636 | return; |
---|
637 | } |
---|
638 | f_ptp = 1; |
---|
639 | cur_idx += 1; |
---|
640 | } else { |
---|
641 | printf("Bad parameter: %s\n", argv[cur_idx]); |
---|
642 | return; |
---|
643 | } |
---|
644 | cur_idx += 1; |
---|
645 | } |
---|
646 | |
---|
647 | printf("ifconfig "); |
---|
648 | |
---|
649 | if (iface != NULL) { |
---|
650 | printf("%s ", iface); |
---|
651 | if (f_ip != 0) { |
---|
652 | char str[256]; |
---|
653 | inet_ntop(AF_INET, &ipaddr.sin_addr, str, 256); |
---|
654 | printf("%s ", str); |
---|
655 | } |
---|
656 | if (f_netmask != 0) { |
---|
657 | char str[256]; |
---|
658 | inet_ntop(AF_INET, &netmask.sin_addr, str, 256); |
---|
659 | printf("netmask %s ", str); |
---|
660 | } |
---|
661 | if (f_bcast != 0) { |
---|
662 | char str[256]; |
---|
663 | inet_ntop(AF_INET, &broadcast.sin_addr, str, 256); |
---|
664 | printf("broadcast %s ", str); |
---|
665 | } |
---|
666 | if (f_ptp != 0) { |
---|
667 | char str[256]; |
---|
668 | inet_ntop(AF_INET, &dstaddr.sin_addr, str, 256); |
---|
669 | printf("pointopoint %s ", str); |
---|
670 | } |
---|
671 | if (f_up != 0) { |
---|
672 | printf("up\n"); |
---|
673 | } else if (f_down != 0) { |
---|
674 | printf("down\n"); |
---|
675 | } else { |
---|
676 | printf("\n"); |
---|
677 | } |
---|
678 | } |
---|
679 | |
---|
680 | if ((iface == NULL) || ((f_ip == 0) && (f_down == 0) && (f_up == 0))) { |
---|
681 | rtems_bsdnet_show_if_stats(); |
---|
682 | return; |
---|
683 | } |
---|
684 | |
---|
685 | flags = 0; |
---|
686 | if (f_netmask) { |
---|
687 | rc = rtems_bsdnet_ifconfig(iface, SIOCSIFNETMASK, &netmask); |
---|
688 | if (rc < 0) { |
---|
689 | printf("Could not set netmask: %s\n", strerror(errno)); |
---|
690 | return; |
---|
691 | } |
---|
692 | } |
---|
693 | if (f_bcast) { |
---|
694 | rc = rtems_bsdnet_ifconfig(iface, SIOCSIFBRDADDR, &broadcast); |
---|
695 | if (rc < 0) { |
---|
696 | printf("Could not set broadcast: %s\n", strerror(errno)); |
---|
697 | return; |
---|
698 | } |
---|
699 | } |
---|
700 | if (f_ptp) { |
---|
701 | rc = rtems_bsdnet_ifconfig(iface, SIOCSIFDSTADDR, &dstaddr); |
---|
702 | if (rc < 0) { |
---|
703 | printf("Could not set destination address: %s\n", strerror(errno)); |
---|
704 | return; |
---|
705 | } |
---|
706 | flags |= IFF_POINTOPOINT; |
---|
707 | } |
---|
708 | |
---|
709 | /* This must come _after_ setting the netmask, broadcast addresses */ |
---|
710 | if (f_ip) { |
---|
711 | rc = rtems_bsdnet_ifconfig(iface, SIOCSIFADDR, &ipaddr); |
---|
712 | if (rc < 0) { |
---|
713 | printf("Could not set IP address: %s\n", strerror(errno)); |
---|
714 | return; |
---|
715 | } |
---|
716 | } |
---|
717 | if (f_up != 0) { |
---|
718 | flags |= IFF_UP; |
---|
719 | } |
---|
720 | if (f_down != 0) { |
---|
721 | printf("Warning: taking interfaces down is not supported\n"); |
---|
722 | } |
---|
723 | |
---|
724 | rc = rtems_bsdnet_ifconfig(iface, SIOCSIFFLAGS, &flags); |
---|
725 | if (rc < 0) { |
---|
726 | printf("Could not set interface flags: %s\n", strerror(errno)); |
---|
727 | return; |
---|
728 | } |
---|
729 | } |
---|
730 | |
---|
731 | void mon_route(int argc, char *argv[], unsigned32 command_arg, bool verbose) |
---|
732 | { |
---|
733 | int cmd; |
---|
734 | struct sockaddr_in dst; |
---|
735 | struct sockaddr_in gw; |
---|
736 | struct sockaddr_in netmask; |
---|
737 | int f_host; |
---|
738 | int f_gw = 0; |
---|
739 | int cur_idx; |
---|
740 | int flags; |
---|
741 | int rc; |
---|
742 | |
---|
743 | memset(&dst, 0, sizeof(dst)); |
---|
744 | memset(&gw, 0, sizeof(gw)); |
---|
745 | memset(&netmask, 0, sizeof(netmask)); |
---|
746 | dst.sin_len = sizeof(dst); |
---|
747 | dst.sin_family = AF_INET; |
---|
748 | dst.sin_addr.s_addr = inet_addr("0.0.0.0"); |
---|
749 | gw.sin_len = sizeof(gw); |
---|
750 | gw.sin_family = AF_INET; |
---|
751 | gw.sin_addr.s_addr = inet_addr("0.0.0.0"); |
---|
752 | netmask.sin_len = sizeof(netmask); |
---|
753 | netmask.sin_family = AF_INET; |
---|
754 | netmask.sin_addr.s_addr = inet_addr("255.255.255.0"); |
---|
755 | |
---|
756 | if (argc < 2) { |
---|
757 | rtems_bsdnet_show_inet_routes(); |
---|
758 | return; |
---|
759 | } |
---|
760 | |
---|
761 | if (strcmp(argv[1], "add") == 0) { |
---|
762 | cmd = RTM_ADD; |
---|
763 | } else if (strcmp(argv[1], "del") == 0) { |
---|
764 | cmd = RTM_DELETE; |
---|
765 | } else { |
---|
766 | printf("invalid command: %s\n", argv[1]); |
---|
767 | printf("\tit should be 'add' or 'del'\n"); |
---|
768 | return; |
---|
769 | } |
---|
770 | |
---|
771 | if (argc < 3) { |
---|
772 | printf("not enough arguments\n"); |
---|
773 | return; |
---|
774 | } |
---|
775 | |
---|
776 | if (strcmp(argv[2], "-host") == 0) { |
---|
777 | f_host = 1; |
---|
778 | } else if (strcmp(argv[2], "-net") == 0) { |
---|
779 | f_host = 0; |
---|
780 | } else { |
---|
781 | printf("Invalid type: %s\n", argv[1]); |
---|
782 | printf("\tit should be '-host' or '-net'\n"); |
---|
783 | return; |
---|
784 | } |
---|
785 | |
---|
786 | if (argc < 4) { |
---|
787 | printf("not enough arguments\n"); |
---|
788 | return; |
---|
789 | } |
---|
790 | |
---|
791 | inet_pton(AF_INET, argv[3], &dst.sin_addr); |
---|
792 | |
---|
793 | cur_idx = 4; |
---|
794 | while(cur_idx < argc) { |
---|
795 | if (strcmp(argv[cur_idx], "gw") == 0) { |
---|
796 | if ((cur_idx +1) >= argc) { |
---|
797 | printf("no gateway address\n"); |
---|
798 | return; |
---|
799 | } |
---|
800 | f_gw = 1; |
---|
801 | inet_pton(AF_INET, argv[cur_idx + 1], &gw.sin_addr); |
---|
802 | cur_idx += 1; |
---|
803 | } else if(strcmp(argv[cur_idx], "netmask") == 0) { |
---|
804 | if ((cur_idx +1) >= argc) { |
---|
805 | printf("no netmask address\n"); |
---|
806 | return; |
---|
807 | } |
---|
808 | f_gw = 1; |
---|
809 | inet_pton(AF_INET, argv[cur_idx + 1], &netmask.sin_addr); |
---|
810 | cur_idx += 1; |
---|
811 | } else { |
---|
812 | printf("Unknown argument\n"); |
---|
813 | return; |
---|
814 | } |
---|
815 | cur_idx += 1; |
---|
816 | } |
---|
817 | |
---|
818 | flags = RTF_STATIC; |
---|
819 | if (f_gw != 0) { |
---|
820 | flags |= RTF_GATEWAY; |
---|
821 | } |
---|
822 | if (f_host != 0) { |
---|
823 | flags |= RTF_HOST; |
---|
824 | } |
---|
825 | |
---|
826 | rc = rtems_bsdnet_rtrequest(cmd, &dst, &gw, &netmask, flags, NULL); |
---|
827 | if (rc < 0) { |
---|
828 | printf("Error adding route\n"); |
---|
829 | } |
---|
830 | } |
---|
831 | |
---|
832 | Thanks to Jay Monkman <mailto:jtm@smoothmsmoothie.com> for this example |
---|
833 | code. |
---|
834 | |
---|
835 | Time Synchronization Using NTP |
---|
836 | ------------------------------ |
---|
837 | |
---|
838 | .. code-block:: c |
---|
839 | |
---|
840 | int rtems_bsdnet_synchronize_ntp (int interval, rtems_task_priority priority); |
---|
841 | |
---|
842 | If the interval argument is ``0`` the routine synchronizes the RTEMS |
---|
843 | time-of-day clock with the first NTP server in the ``rtems_bsdnet_ntpserve`` |
---|
844 | array and returns. The priority argument is ignored. |
---|
845 | |
---|
846 | If the interval argument is greater than 0, the routine also starts an RTEMS |
---|
847 | task at the specified priority and polls the NTP server every 'interval' |
---|
848 | seconds. NOTE: This mode of operation has not yet been implemented. |
---|
849 | |
---|
850 | On successful synchronization of the RTEMS time-of-day clock the routine |
---|
851 | returns ``0``. If an error occurs a message is printed and the routine returns |
---|
852 | ``-1`` with an error code in errno. There is no timeout - if there is no |
---|
853 | response from an NTP server the routine will wait forever. |
---|