Rich Lane | 5ec97b8 | 2013-01-06 18:04:25 -0800 | [diff] [blame^] | 1 | |
| 2 | """ |
| 3 | Base list class for inheritance. |
| 4 | Most of the list stuff is common; unpacking is the only thing that |
| 5 | is left pure virtual. |
| 6 | """ |
| 7 | |
| 8 | import copy |
| 9 | |
| 10 | class ofp_base_list(object): |
| 11 | """ |
| 12 | Container type to maintain a list of ofp objects |
| 13 | |
| 14 | Data members: |
| 15 | @arg items An array of objects |
| 16 | @arg class_list A tuple of classes that may be added to the list; |
| 17 | If None, no checking is done |
| 18 | @arg name The name to use when displaying the list |
| 19 | |
| 20 | Methods: |
| 21 | @arg pack Pack the structure into a string |
| 22 | @arg unpack Unpack a string to objects, with proper typing |
| 23 | @arg add Add an item to the list; you can directly access |
| 24 | the item member, but add will validate that the added object |
| 25 | is of the right type. |
| 26 | @arg extend Add the items for another list to this list |
| 27 | |
| 28 | """ |
| 29 | |
| 30 | def __init__(self): |
| 31 | self.items = [] |
| 32 | self.class_list = None |
| 33 | self.name = "unspecified" |
| 34 | |
| 35 | def pack(self): |
| 36 | """ |
| 37 | Pack a list of items |
| 38 | |
| 39 | Returns the packed string |
| 40 | """ |
| 41 | packed = "" |
| 42 | for obj in self.items: |
| 43 | packed += obj.pack() |
| 44 | return packed |
| 45 | |
| 46 | def unpack(self, binary_string, bytes=None): |
| 47 | """ |
| 48 | Pure virtual function for a list of items |
| 49 | |
| 50 | Unpack items from a binary string, creating an array |
| 51 | of objects of the appropriate type |
| 52 | |
| 53 | @param binary_string The string to be unpacked |
| 54 | |
| 55 | @param bytes The total length of the list in bytes. |
| 56 | Ignored if decode is True. If None and decode is false, the |
| 57 | list is assumed to extend through the entire string. |
| 58 | |
| 59 | @return The remainder of binary_string that was not parsed |
| 60 | """ |
| 61 | pass |
| 62 | |
| 63 | def add(self, item): |
| 64 | """ |
| 65 | Add an item to a list |
| 66 | |
| 67 | @param item The item to add |
| 68 | @return True if successful, False if not proper type object |
| 69 | |
| 70 | """ |
| 71 | |
| 72 | # Note that the second arg of isinstance can be a list which |
| 73 | # checks that the type of item is in the list |
| 74 | if (self.class_list is not None) and \ |
| 75 | not isinstance(item, tuple(self.class_list)): |
| 76 | return False |
| 77 | |
| 78 | tmp = copy.deepcopy(item) |
| 79 | self.items.append(tmp) |
| 80 | return True |
| 81 | |
| 82 | def remove_type(self, target): |
| 83 | """ |
| 84 | Remove the first item on the list of the given type |
| 85 | |
| 86 | @param target The type of item to search |
| 87 | |
| 88 | @return The object removed, if any; otherwise None |
| 89 | |
| 90 | """ |
| 91 | for index in xrange(len(self.items)): |
| 92 | if self.items[index].type == target: |
| 93 | return self.items.pop(index) |
| 94 | return None |
| 95 | |
| 96 | def find_type(self, target): |
| 97 | """ |
| 98 | Find the first item on the list of the given type |
| 99 | |
| 100 | @param target The type of item to search |
| 101 | |
| 102 | @return The object with the matching type if any; otherwise None |
| 103 | |
| 104 | """ |
| 105 | for index in xrange(len(self.items)): |
| 106 | if self.items[index].type == target: |
| 107 | return self.items[index] |
| 108 | return None |
| 109 | |
| 110 | def extend(self, other): |
| 111 | """ |
| 112 | Add the items in other to this list |
| 113 | |
| 114 | @param other An object of the same type of list whose |
| 115 | entries are to be merged into this list |
| 116 | |
| 117 | @return True if successful. If not successful, the list |
| 118 | may have been modified. |
| 119 | |
| 120 | @todo Check if this is proper deep copy or not |
| 121 | |
| 122 | """ |
| 123 | for act in other.items: |
| 124 | if not self.add(act): |
| 125 | return False |
| 126 | return True |
| 127 | |
| 128 | def __len__(self): |
| 129 | """ |
| 130 | Length of the list packed as a string |
| 131 | """ |
| 132 | length = 0 |
| 133 | for item in self.items: |
| 134 | length += item.__len__() |
| 135 | return length |
| 136 | |
| 137 | def __eq__(self, other): |
| 138 | if type(self) != type(other): |
| 139 | return False |
| 140 | if self.items != other.items: |
| 141 | return False |
| 142 | return True |
| 143 | |
| 144 | def __ne__(self, other): return not self.__eq__(other) |
| 145 | |
| 146 | # Methods to make class iterable |
| 147 | def __iter__(self): |
| 148 | return self.items.__iter__() |
| 149 | |
| 150 | def show(self, prefix=''): |
| 151 | outstr = prefix + self.name + "list with " + str(len(self.items)) + \ |
| 152 | " items\n" |
| 153 | count = 0 |
| 154 | for obj in self.items: |
| 155 | count += 1 |
| 156 | outstr += prefix + " " + self.name + " " + str(count) + ": \n" |
| 157 | outstr += obj.show(prefix + ' ') |
| 158 | return outstr |