1 | .. comment SPDX-License-Identifier: CC-BY-SA-4.0 |
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2 | |
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3 | .. Copyright (C) 2014 Gedare Bloom |
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4 | |
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5 | .. index:: chains |
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6 | |
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7 | Chains |
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8 | ****** |
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9 | |
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10 | Introduction |
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11 | ============ |
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12 | |
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13 | The Chains API is an interface to the Super Core (score) chain |
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14 | implementation. The Super Core uses chains for all list type functions. This |
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15 | includes wait queues and task queues. The Chains API provided by RTEMS is: |
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16 | |
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17 | - rtems_chain_initialize_ - initialize the chain with nodes |
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18 | |
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19 | - rtems_chain_initialize_empty_ - initialize the chain as empty |
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20 | |
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21 | - rtems_chain_is_null_node_ - Is the node NULL ? |
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22 | |
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23 | - rtems_chain_head_ - Return the chain's head |
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24 | |
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25 | - rtems_chain_tail_ - Return the chain's tail |
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26 | |
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27 | - rtems_chain_are_nodes_equal_ - Are the node's equal ? |
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28 | |
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29 | - rtems_chain_is_empty_ - Is the chain empty ? |
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30 | |
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31 | - rtems_chain_is_first_ - Is the Node the first in the chain ? |
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32 | |
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33 | - rtems_chain_is_last_ - Is the Node the last in the chain ? |
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34 | |
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35 | - rtems_chain_has_only_one_node_ - Does the node have one node ? |
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36 | |
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37 | - rtems_chain_node_count_unprotected_ - Returns the node count of the chain (unprotected) |
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38 | |
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39 | - rtems_chain_is_head_ - Is the node the head ? |
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40 | |
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41 | - rtems_chain_is_tail_ - Is the node the tail ? |
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42 | |
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43 | - rtems_chain_extract_ - Extract the node from the chain |
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44 | |
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45 | - rtems_chain_extract_unprotected_ - Extract the node from the chain (unprotected) |
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46 | |
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47 | - rtems_chain_get_ - Return the first node on the chain |
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48 | |
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49 | - rtems_chain_get_unprotected_ - Return the first node on the chain (unprotected) |
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50 | |
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51 | - rtems_chain_insert_ - Insert the node into the chain |
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52 | |
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53 | - rtems_chain_insert_unprotected_ - Insert the node into the chain (unprotected) |
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54 | |
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55 | - rtems_chain_append_ - Append the node to chain |
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56 | |
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57 | - rtems_chain_append_unprotected_ - Append the node to chain (unprotected) |
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58 | |
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59 | - rtems_chain_prepend_ - Prepend the node to the end of the chain |
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60 | |
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61 | - rtems_chain_prepend_unprotected_ - Prepend the node to chain (unprotected) |
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62 | |
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63 | Background |
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64 | ========== |
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65 | |
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66 | The Chains API maps to the Super Core Chains API. Chains are implemented as a |
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67 | double linked list of nodes anchored to a control node. The list starts at the |
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68 | control node and is terminated at the control node. A node has previous and |
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69 | next pointers. Being a double linked list nodes can be inserted and removed |
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70 | without the need to travse the chain. |
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71 | |
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72 | Chains have a small memory footprint and can be used in interrupt service |
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73 | routines and are thread safe in a multi-threaded environment. The directives |
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74 | list which operations disable interrupts. |
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75 | |
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76 | Chains are very useful in Board Support packages and applications. |
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77 | |
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78 | Nodes |
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79 | ----- |
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80 | |
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81 | A chain is made up from nodes that orginate from a chain control object. A node |
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82 | is of type ``rtems_chain_node``. The node is designed to be part of a user data |
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83 | structure and a cast is used to move from the node address to the user data |
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84 | structure address. For example: |
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85 | |
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86 | .. code-block:: c |
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87 | |
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88 | typedef struct foo |
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89 | { |
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90 | rtems_chain_node node; |
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91 | int bar; |
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92 | } foo; |
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93 | |
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94 | creates a type ``foo`` that can be placed on a chain. To get the foo structure |
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95 | from the list you perform the following: |
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96 | |
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97 | .. code-block:: c |
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98 | |
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99 | foo* get_foo(rtems_chain_control* control) |
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100 | { |
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101 | return (foo*) rtems_chain_get(control); |
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102 | } |
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103 | |
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104 | The node is placed at the start of the user's structure to allow the node |
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105 | address on the chain to be easly cast to the user's structure address. |
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106 | |
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107 | Controls |
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108 | -------- |
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109 | |
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110 | A chain is anchored with a control object. Chain control provide the user with |
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111 | access to the nodes on the chain. The control is head of the node. |
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112 | |
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113 | .. code-block:: c |
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114 | |
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115 | [Control] |
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116 | first ------------------------> |
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117 | permanent_null <--------------- [NODE] |
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118 | last -------------------------> |
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119 | |
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120 | The implementation does not require special checks for manipulating the first |
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121 | and last nodes on the chain. To accomplish this the ``rtems_chain_control`` |
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122 | structure is treated as two overlapping ``rtems_chain_node`` structures. The |
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123 | permanent head of the chain overlays a node structure on the first and |
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124 | ``permanent_null`` fields. The ``permanent_tail`` of the chain overlays a node |
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125 | structure on the ``permanent_null`` and ``last`` elements of the structure. |
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126 | |
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127 | Operations |
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128 | ========== |
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129 | |
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130 | Multi-threading |
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131 | --------------- |
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132 | |
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133 | Chains are designed to be used in a multi-threading environment. The directives |
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134 | list which operations mask interrupts. Chains supports tasks and interrupt |
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135 | service routines appending and extracting nodes with out the need for extra |
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136 | locks. Chains how-ever cannot insure the integrity of a chain for all |
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137 | operations. This is the responsibility of the user. For example an interrupt |
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138 | service routine extracting nodes while a task is iterating over the chain can |
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139 | have unpredictable results. |
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140 | |
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141 | Creating a Chain |
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142 | ---------------- |
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143 | |
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144 | To create a chain you need to declare a chain control then add nodes |
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145 | to the control. Consider a user structure and chain control: |
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146 | |
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147 | .. code-block:: c |
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148 | |
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149 | typedef struct foo |
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150 | { |
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151 | rtems_chain_node node; |
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152 | uint8_t char* data; |
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153 | } foo; |
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154 | rtems_chain_control chain; |
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155 | |
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156 | Add nodes with the following code: |
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157 | |
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158 | .. code-block:: c |
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159 | |
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160 | rtems_chain_initialize_empty (&chain); |
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161 | |
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162 | for (i = 0; i < count; i++) |
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163 | { |
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164 | foo* bar = malloc (sizeof (foo)); |
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165 | if (!bar) |
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166 | return -1; |
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167 | bar->data = malloc (size); |
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168 | rtems_chain_append (&chain, &bar->node); |
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169 | } |
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170 | |
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171 | The chain is initialized and the nodes allocated and appended to the |
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172 | chain. This is an example of a pool of buffers. |
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173 | |
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174 | .. index:: chain iterate |
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175 | |
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176 | Iterating a Chain |
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177 | ----------------- |
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178 | |
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179 | Iterating a chain is a common function. The example shows how to iterate the |
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180 | buffer pool chain created in the last section to find buffers starting with a |
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181 | specific string. If the buffer is located it is extracted from the chain and |
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182 | placed on another chain: |
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183 | |
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184 | .. code-block:: c |
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185 | |
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186 | void foobar (const char* match, |
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187 | rtems_chain_control* chain, |
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188 | rtems_chain_control* out) |
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189 | { |
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190 | rtems_chain_node* node; |
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191 | foo* bar; |
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192 | |
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193 | rtems_chain_initialize_empty (out); |
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194 | |
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195 | node = chain->first; |
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196 | while (!rtems_chain_is_tail (chain, node)) |
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197 | { |
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198 | bar = (foo*) node; |
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199 | rtems_chain_node* next_node = node->next; |
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200 | if (strcmp (match, bar->data) == 0) |
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201 | { |
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202 | rtems_chain_extract (node); |
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203 | rtems_chain_append (out, node); |
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204 | } |
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205 | node = next_node; |
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206 | } |
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207 | } |
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208 | |
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209 | Directives |
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210 | ========== |
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211 | |
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212 | The section details the Chains directives. |
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213 | |
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214 | .. COMMENT: Initialize this Chain With Nodes |
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215 | |
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216 | .. raw:: latex |
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217 | |
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218 | \clearpage |
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219 | |
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220 | .. _rtems_chain_initialize: |
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221 | |
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222 | .. index:: chain initialize |
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223 | .. index:: rtems_chain_initialize |
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224 | |
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225 | Initialize Chain With Nodes |
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226 | --------------------------- |
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227 | |
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228 | CALLING SEQUENCE: |
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229 | .. code-block:: c |
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230 | |
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231 | void rtems_chain_initialize( |
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232 | rtems_chain_control *the_chain, |
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233 | void *starting_address, |
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234 | size_t number_nodes, |
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235 | size_t node_size |
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236 | ) |
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237 | |
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238 | RETURNS: |
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239 | Returns nothing. |
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240 | |
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241 | DESCRIPTION: |
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242 | This function take in a pointer to a chain control and initializes it to |
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243 | contain a set of chain nodes. The chain will contain ``number_nodes`` |
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244 | chain nodes from the memory pointed to by ``start_address``. Each node is |
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245 | assumed to be ``node_size`` bytes. |
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246 | |
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247 | NOTES: |
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248 | This call will discard any nodes on the chain. |
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249 | |
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250 | This call does NOT inititialize any user data on each node. |
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251 | |
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252 | .. COMMENT: Initialize this Chain as Empty |
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253 | |
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254 | .. raw:: latex |
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255 | |
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256 | \clearpage |
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257 | |
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258 | .. _rtems_chain_initialize_empty: |
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259 | |
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260 | .. index:: chain initialize empty |
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261 | .. index:: rtems_chain_initialize_empty |
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262 | |
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263 | Initialize Empty |
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264 | ---------------- |
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265 | |
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266 | CALLING SEQUENCE: |
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267 | .. code-block:: c |
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268 | |
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269 | void rtems_chain_initialize_empty( |
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270 | rtems_chain_control *the_chain |
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271 | ); |
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272 | |
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273 | RETURNS: |
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274 | Returns nothing. |
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275 | |
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276 | DESCRIPTION: |
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277 | This function take in a pointer to a chain control and initializes it to |
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278 | empty. |
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279 | |
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280 | NOTES: |
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281 | This call will discard any nodes on the chain. |
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282 | |
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283 | .. raw:: latex |
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284 | |
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285 | \clearpage |
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286 | |
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287 | .. _rtems_chain_is_null_node: |
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288 | |
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289 | .. index:: chain is node null |
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290 | .. index:: rtems_chain_is_null_node |
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291 | |
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292 | Is Null Node ? |
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293 | -------------- |
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294 | |
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295 | CALLING SEQUENCE: |
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296 | .. code-block:: c |
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297 | |
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298 | bool rtems_chain_is_null_node( |
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299 | const rtems_chain_node *the_node |
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300 | ); |
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301 | |
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302 | RETURNS: |
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303 | Returns ``true`` is the node point is NULL and ``false`` if the node is not |
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304 | NULL. |
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305 | |
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306 | DESCRIPTION: |
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307 | Tests the node to see if it is a NULL returning ``true`` if a null. |
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308 | |
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309 | .. raw:: latex |
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310 | |
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311 | \clearpage |
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312 | |
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313 | .. _rtems_chain_head: |
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314 | |
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315 | .. index:: chain get head |
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316 | .. index:: rtems_chain_head |
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317 | |
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318 | Head |
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319 | ---- |
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320 | |
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321 | CALLING SEQUENCE: |
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322 | .. code-block:: c |
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323 | |
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324 | rtems_chain_node *rtems_chain_head( |
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325 | rtems_chain_control *the_chain |
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326 | ) |
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327 | |
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328 | RETURNS: |
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329 | Returns the permanent head node of the chain. |
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330 | |
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331 | DESCRIPTION: |
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332 | This function returns a pointer to the first node on the chain. |
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333 | |
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334 | .. raw:: latex |
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335 | |
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336 | \clearpage |
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337 | |
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338 | .. _rtems_chain_tail: |
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339 | |
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340 | .. index:: chain get tail |
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341 | .. index:: rtems_chain_tail |
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342 | |
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343 | Tail |
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344 | ---- |
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345 | |
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346 | CALLING SEQUENCE: |
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347 | .. code-block:: c |
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348 | |
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349 | rtems_chain_node *rtems_chain_tail( |
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350 | rtems_chain_control *the_chain |
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351 | ); |
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352 | |
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353 | RETURNS: |
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354 | Returns the permanent tail node of the chain. |
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355 | |
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356 | DESCRIPTION: |
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357 | This function returns a pointer to the last node on the chain. |
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358 | |
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359 | .. raw:: latex |
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360 | |
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361 | \clearpage |
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362 | |
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363 | .. _rtems_chain_are_nodes_equal: |
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364 | |
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365 | .. index:: chare are nodes equal |
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366 | .. index:: rtems_chain_are_nodes_equal |
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367 | |
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368 | Are Two Nodes Equal ? |
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369 | --------------------- |
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370 | |
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371 | CALLING SEQUENCE: |
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372 | .. code-block:: c |
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373 | |
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374 | bool rtems_chain_are_nodes_equal( |
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375 | const rtems_chain_node *left, |
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376 | const rtems_chain_node *right |
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377 | ); |
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378 | |
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379 | RETURNS: |
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380 | This function returns ``true`` if the left node and the right node are |
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381 | equal, and ``false`` otherwise. |
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382 | |
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383 | DESCRIPTION: |
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384 | This function returns ``true`` if the left node and the right node are |
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385 | equal, and ``false`` otherwise. |
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386 | |
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387 | .. raw:: latex |
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388 | |
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389 | \clearpage |
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390 | |
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391 | .. _rtems_chain_is_empty: |
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392 | |
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393 | .. index:: chain is chain empty |
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394 | .. index:: rtems_chain_is_empty |
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395 | |
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396 | Is the Chain Empty |
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397 | ------------------ |
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398 | |
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399 | CALLING SEQUENCE: |
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400 | .. code-block:: c |
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401 | |
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402 | bool rtems_chain_is_empty( |
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403 | rtems_chain_control *the_chain |
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404 | ); |
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405 | |
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406 | RETURNS: |
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407 | This function returns ``true`` if there a no nodes on the chain and |
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408 | ``false`` otherwise. |
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409 | |
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410 | DESCRIPTION: |
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411 | This function returns ``true`` if there a no nodes on the chain and |
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412 | ``false`` otherwise. |
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413 | |
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414 | .. raw:: latex |
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415 | |
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416 | \clearpage |
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417 | |
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418 | .. _rtems_chain_is_first: |
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419 | |
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420 | .. index:: chain is node the first |
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421 | .. index:: rtems_chain_is_first |
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422 | |
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423 | Is this the First Node on the Chain ? |
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424 | ------------------------------------- |
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425 | |
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426 | CALLING SEQUENCE: |
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427 | .. code-block:: c |
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428 | |
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429 | bool rtems_chain_is_first( |
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430 | const rtems_chain_node *the_node |
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431 | ); |
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432 | |
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433 | RETURNS: |
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434 | This function returns ``true`` if the node is the first node on a chain and |
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435 | ``false`` otherwise. |
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436 | |
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437 | DESCRIPTION: |
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438 | This function returns ``true`` if the node is the first node on a chain and |
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439 | ``false`` otherwise. |
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440 | |
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441 | .. raw:: latex |
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442 | |
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443 | \clearpage |
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444 | |
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445 | .. _rtems_chain_is_last: |
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446 | |
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447 | .. index:: chain is node the last |
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448 | .. index:: rtems_chain_is_last |
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449 | |
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450 | Is this the Last Node on the Chain ? |
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451 | ------------------------------------ |
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452 | |
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453 | CALLING SEQUENCE: |
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454 | .. code-block:: c |
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455 | |
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456 | bool rtems_chain_is_last( |
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457 | const rtems_chain_node *the_node |
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458 | ); |
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459 | |
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460 | RETURNS: |
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461 | This function returns ``true`` if the node is the last node on a chain and |
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462 | ``false`` otherwise. |
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463 | |
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464 | DESCRIPTION: |
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465 | This function returns ``true`` if the node is the last node on a chain and |
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466 | ``false`` otherwise. |
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467 | |
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468 | .. raw:: latex |
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469 | |
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470 | \clearpage |
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471 | |
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472 | .. _rtems_chain_has_only_one_node: |
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473 | |
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474 | .. index:: chain only one node |
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475 | .. index:: rtems_chain_has_only_one_node |
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476 | |
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477 | Does this Chain have only One Node ? |
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478 | ------------------------------------ |
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479 | |
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480 | CALLING SEQUENCE: |
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481 | .. code-block:: c |
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482 | |
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483 | bool rtems_chain_has_only_one_node( |
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484 | const rtems_chain_control *the_chain |
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485 | ); |
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486 | |
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487 | RETURNS: |
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488 | This function returns ``true`` if there is only one node on the chain and |
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489 | ``false`` otherwise. |
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490 | |
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491 | DESCRIPTION: |
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492 | This function returns ``true`` if there is only one node on the chain and |
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493 | ``false`` otherwise. |
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494 | |
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495 | .. raw:: latex |
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496 | |
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497 | \clearpage |
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498 | |
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499 | .. _rtems_chain_node_count_unprotected: |
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500 | |
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501 | .. index:: chain only one node |
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502 | .. index:: rtems_chain_node_count_unprotected |
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503 | |
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504 | Returns the node count of the chain (unprotected) |
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505 | ------------------------------------------------- |
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506 | |
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507 | CALLING SEQUENCE: |
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508 | .. code-block:: c |
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509 | |
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510 | size_t rtems_chain_node_count_unprotected( |
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511 | const rtems_chain_control *the_chain |
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512 | ); |
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513 | |
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514 | RETURNS: |
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515 | This function returns the node count of the chain. |
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516 | |
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517 | DESCRIPTION: |
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518 | This function returns the node count of the chain. |
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519 | |
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520 | .. raw:: latex |
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521 | |
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522 | \clearpage |
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523 | |
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524 | .. _rtems_chain_is_head: |
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525 | |
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526 | .. index:: chain is node the head |
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527 | .. index:: rtems_chain_is_head |
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528 | |
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529 | Is this Node the Chain Head ? |
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530 | ----------------------------- |
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531 | |
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532 | CALLING SEQUENCE: |
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533 | .. code-block:: c |
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534 | |
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535 | bool rtems_chain_is_head( |
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536 | rtems_chain_control *the_chain, |
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537 | rtems_const chain_node *the_node |
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538 | ); |
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539 | |
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540 | RETURNS: |
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541 | This function returns ``true`` if the node is the head of the chain and |
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542 | ``false`` otherwise. |
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543 | |
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544 | DESCRIPTION: |
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545 | This function returns ``true`` if the node is the head of the chain and |
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546 | ``false`` otherwise. |
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547 | |
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548 | .. raw:: latex |
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549 | |
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550 | \clearpage |
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551 | |
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552 | .. _rtems_chain_is_tail: |
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553 | |
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554 | .. index:: chain is node the tail |
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555 | .. index:: rtems_chain_is_tail |
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556 | |
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557 | Is this Node the Chain Tail ? |
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558 | ----------------------------- |
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559 | |
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560 | CALLING SEQUENCE: |
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561 | .. code-block:: c |
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562 | |
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563 | bool rtems_chain_is_tail( |
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564 | rtems_chain_control *the_chain, |
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565 | const rtems_chain_node *the_node |
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566 | ) |
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567 | |
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568 | RETURNS: |
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569 | This function returns ``true`` if the node is the tail of the chain and |
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570 | ``false`` otherwise. |
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571 | |
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572 | DESCRIPTION: |
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573 | This function returns ``true`` if the node is the tail of the chain and |
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574 | ``false`` otherwise. |
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575 | |
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576 | .. raw:: latex |
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577 | |
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578 | \clearpage |
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579 | |
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580 | .. _rtems_chain_extract: |
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581 | |
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582 | .. index:: chain extract a node |
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583 | .. index:: rtems_chain_extract |
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584 | |
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585 | Extract a Node |
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586 | -------------- |
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587 | |
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588 | CALLING SEQUENCE: |
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589 | .. code-block:: c |
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590 | |
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591 | void rtems_chain_extract( |
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592 | rtems_chain_node *the_node |
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593 | ); |
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594 | |
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595 | RETURNS: |
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596 | Returns nothing. |
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597 | |
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598 | DESCRIPTION: |
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599 | This routine extracts the node from the chain on which it resides. |
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600 | |
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601 | NOTES: |
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602 | Interrupts are disabled while extracting the node to ensure the atomicity |
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603 | of the operation. |
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604 | |
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605 | Use ``rtems_chain_extract_unprotected`` to avoid disabling of interrupts. |
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606 | |
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607 | .. raw:: latex |
---|
608 | |
---|
609 | \clearpage |
---|
610 | |
---|
611 | .. _rtems_chain_extract_unprotected: |
---|
612 | |
---|
613 | .. index:: chain extract a node unprotected |
---|
614 | .. index:: rtems_chain_extract_unprotected |
---|
615 | |
---|
616 | Extract a Node (unprotected) |
---|
617 | ---------------------------- |
---|
618 | |
---|
619 | CALLING SEQUENCE: |
---|
620 | .. code-block:: c |
---|
621 | |
---|
622 | void rtems_chain_extract_unprotected( |
---|
623 | rtems_chain_node *the_node |
---|
624 | ); |
---|
625 | |
---|
626 | RETURNS: |
---|
627 | Returns nothing. |
---|
628 | |
---|
629 | DESCRIPTION: |
---|
630 | This routine extracts the node from the chain on which it resides. |
---|
631 | |
---|
632 | NOTES: |
---|
633 | The function does nothing to ensure the atomicity of the operation. |
---|
634 | |
---|
635 | .. raw:: latex |
---|
636 | |
---|
637 | \clearpage |
---|
638 | |
---|
639 | .. _rtems_chain_get: |
---|
640 | |
---|
641 | .. index:: chain get first node |
---|
642 | .. index:: rtems_chain_get |
---|
643 | |
---|
644 | Get the First Node |
---|
645 | ------------------ |
---|
646 | |
---|
647 | CALLING SEQUENCE: |
---|
648 | .. code-block:: c |
---|
649 | |
---|
650 | rtems_chain_node *rtems_chain_get( |
---|
651 | rtems_chain_control *the_chain |
---|
652 | ); |
---|
653 | |
---|
654 | RETURNS: |
---|
655 | Returns a pointer a node. If a node was removed, then a pointer to that |
---|
656 | node is returned. If the chain was empty, then ``NULL`` is returned. |
---|
657 | |
---|
658 | DESCRIPTION: |
---|
659 | This function removes the first node from the chain and returns a pointer |
---|
660 | to that node. If the chain is empty, then ``NULL`` is returned. |
---|
661 | |
---|
662 | NOTES: |
---|
663 | Interrupts are disabled while obtaining the node to ensure the atomicity of |
---|
664 | the operation. |
---|
665 | |
---|
666 | Use ``rtems_chain_get_unprotected()`` to avoid disabling of interrupts. |
---|
667 | |
---|
668 | .. raw:: latex |
---|
669 | |
---|
670 | \clearpage |
---|
671 | |
---|
672 | .. _rtems_chain_get_unprotected: |
---|
673 | |
---|
674 | .. index:: chain get first node |
---|
675 | .. index:: rtems_chain_get_unprotected |
---|
676 | |
---|
677 | Get the First Node (unprotected) |
---|
678 | -------------------------------- |
---|
679 | |
---|
680 | CALLING SEQUENCE: |
---|
681 | .. code-block:: c |
---|
682 | |
---|
683 | rtems_chain_node *rtems_chain_get_unprotected( |
---|
684 | rtems_chain_control *the_chain |
---|
685 | ); |
---|
686 | |
---|
687 | RETURNS: |
---|
688 | A pointer to the former first node is returned. |
---|
689 | |
---|
690 | DESCRIPTION: |
---|
691 | Removes the first node from the chain and returns a pointer to it. In case |
---|
692 | the chain was empty, then the results are unpredictable. |
---|
693 | |
---|
694 | NOTES: |
---|
695 | The function does nothing to ensure the atomicity of the operation. |
---|
696 | |
---|
697 | .. raw:: latex |
---|
698 | |
---|
699 | \clearpage |
---|
700 | |
---|
701 | .. _rtems_chain_insert: |
---|
702 | |
---|
703 | .. index:: chain insert a node |
---|
704 | .. index:: rtems_chain_insert |
---|
705 | |
---|
706 | Insert a Node |
---|
707 | ------------- |
---|
708 | |
---|
709 | CALLING SEQUENCE: |
---|
710 | .. code-block:: c |
---|
711 | |
---|
712 | void rtems_chain_insert( |
---|
713 | rtems_chain_node *after_node, |
---|
714 | rtems_chain_node *the_node |
---|
715 | ); |
---|
716 | |
---|
717 | RETURNS: |
---|
718 | Returns nothing. |
---|
719 | |
---|
720 | DESCRIPTION: |
---|
721 | This routine inserts a node on a chain immediately following the specified |
---|
722 | node. |
---|
723 | |
---|
724 | NOTES: |
---|
725 | Interrupts are disabled during the insert to ensure the atomicity of the |
---|
726 | operation. |
---|
727 | |
---|
728 | Use ``rtems_chain_insert_unprotected()`` to avoid disabling of interrupts. |
---|
729 | |
---|
730 | .. raw:: latex |
---|
731 | |
---|
732 | \clearpage |
---|
733 | |
---|
734 | .. _rtems_chain_insert_unprotected: |
---|
735 | |
---|
736 | .. index:: chain insert a node unprotected |
---|
737 | .. index:: rtems_chain_insert_unprotected |
---|
738 | |
---|
739 | Insert a Node (unprotected) |
---|
740 | --------------------------- |
---|
741 | |
---|
742 | CALLING SEQUENCE: |
---|
743 | .. code-block:: c |
---|
744 | |
---|
745 | void rtems_chain_insert_unprotected( |
---|
746 | rtems_chain_node *after_node, |
---|
747 | rtems_chain_node *the_node |
---|
748 | ); |
---|
749 | |
---|
750 | RETURNS: |
---|
751 | Returns nothing. |
---|
752 | |
---|
753 | DESCRIPTION: |
---|
754 | This routine inserts a node on a chain immediately following the specified |
---|
755 | node. |
---|
756 | |
---|
757 | NOTES: |
---|
758 | The function does nothing to ensure the atomicity of the operation. |
---|
759 | |
---|
760 | .. raw:: latex |
---|
761 | |
---|
762 | \clearpage |
---|
763 | |
---|
764 | .. _rtems_chain_append: |
---|
765 | |
---|
766 | .. index:: chain append a node |
---|
767 | .. index:: rtems_chain_append |
---|
768 | |
---|
769 | Append a Node |
---|
770 | ------------- |
---|
771 | |
---|
772 | CALLING SEQUENCE: |
---|
773 | .. code-block:: c |
---|
774 | |
---|
775 | void rtems_chain_append( |
---|
776 | rtems_chain_control *the_chain, |
---|
777 | rtems_chain_node *the_node |
---|
778 | ); |
---|
779 | |
---|
780 | RETURNS: |
---|
781 | Returns nothing. |
---|
782 | |
---|
783 | DESCRIPTION: |
---|
784 | This routine appends a node to the end of a chain. |
---|
785 | |
---|
786 | NOTES: |
---|
787 | Interrupts are disabled during the append to ensure the atomicity of the |
---|
788 | operation. |
---|
789 | |
---|
790 | Use ``rtems_chain_append_unprotected`` to avoid disabling of interrupts. |
---|
791 | |
---|
792 | .. raw:: latex |
---|
793 | |
---|
794 | \clearpage |
---|
795 | |
---|
796 | .. _rtems_chain_append_unprotected: |
---|
797 | |
---|
798 | .. index:: chain append a node unprotected |
---|
799 | .. index:: rtems_chain_append_unprotected |
---|
800 | |
---|
801 | Append a Node (unprotected) |
---|
802 | --------------------------- |
---|
803 | |
---|
804 | CALLING SEQUENCE: |
---|
805 | .. code-block:: c |
---|
806 | |
---|
807 | void rtems_chain_append_unprotected( |
---|
808 | rtems_chain_control *the_chain, |
---|
809 | rtems_chain_node *the_node |
---|
810 | ); |
---|
811 | |
---|
812 | RETURNS: |
---|
813 | Returns nothing. |
---|
814 | |
---|
815 | DESCRIPTION: |
---|
816 | This routine appends a node to the end of a chain. |
---|
817 | |
---|
818 | NOTES: |
---|
819 | The function does nothing to ensure the atomicity of the operation. |
---|
820 | |
---|
821 | .. raw:: latex |
---|
822 | |
---|
823 | \clearpage |
---|
824 | |
---|
825 | .. _rtems_chain_prepend: |
---|
826 | |
---|
827 | .. index:: prepend node |
---|
828 | .. index:: rtems_chain_prepend |
---|
829 | |
---|
830 | Prepend a Node |
---|
831 | -------------- |
---|
832 | |
---|
833 | CALLING SEQUENCE: |
---|
834 | .. code-block:: c |
---|
835 | |
---|
836 | void rtems_chain_prepend( |
---|
837 | rtems_chain_control *the_chain, |
---|
838 | rtems_chain_node *the_node |
---|
839 | ); |
---|
840 | |
---|
841 | RETURNS: |
---|
842 | Returns nothing. |
---|
843 | |
---|
844 | DESCRIPTION: |
---|
845 | This routine prepends a node to the front of the chain. |
---|
846 | |
---|
847 | NOTES: |
---|
848 | Interrupts are disabled during the prepend to ensure the atomicity of the |
---|
849 | operation. |
---|
850 | |
---|
851 | Use ``rtems_chain_prepend_unprotected`` to avoid disabling of interrupts. |
---|
852 | |
---|
853 | .. raw:: latex |
---|
854 | |
---|
855 | \clearpage |
---|
856 | |
---|
857 | .. _rtems_chain_prepend_unprotected: |
---|
858 | |
---|
859 | .. index:: prepend node unprotected |
---|
860 | .. index:: rtems_chain_prepend_unprotected |
---|
861 | |
---|
862 | Prepend a Node (unprotected) |
---|
863 | ---------------------------- |
---|
864 | |
---|
865 | CALLING SEQUENCE: |
---|
866 | .. code-block:: c |
---|
867 | |
---|
868 | void rtems_chain_prepend_unprotected( |
---|
869 | rtems_chain_control *the_chain, |
---|
870 | rtems_chain_node *the_node |
---|
871 | ); |
---|
872 | |
---|
873 | RETURNS: |
---|
874 | Returns nothing. |
---|
875 | |
---|
876 | DESCRIPTION: |
---|
877 | This routine prepends a node to the front of the chain. |
---|
878 | |
---|
879 | NOTES: |
---|
880 | The function does nothing to ensure the atomicity of the operation. |
---|