/usr/lib/grass72/include/grass/iostream/queue.h is in grass-dev 7.2.0-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 | /****************************************************************************
*
* MODULE: iostream
*
* COPYRIGHT (C) 2007 Laura Toma
*
*
* Iostream is a library that implements streams, external memory
* sorting on streams, and an external memory priority queue on
* streams. These are the fundamental components used in external
* memory algorithms.
* Credits: The library was developed by Laura Toma. The kernel of
* class STREAM is based on the similar class existent in the GPL TPIE
* project developed at Duke University. The sorting and priority
* queue have been developed by Laura Toma based on communications
* with Rajiv Wickremesinghe. The library was developed as part of
* porting Terraflow to GRASS in 2001. PEARL upgrades in 2003 by
* Rajiv Wickremesinghe as part of the Terracost project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details. *
* **************************************************************************/
#ifndef QUEUE_H
#define QUEUE_H
#include <assert.h>
#include <iostream>
template<class T>
class queue {
private:
T *data;
int size;
int head; // first valid location (if data)
int tail; // next free location
int len;
void grow();
public:
queue(int size=4096);
~queue();
bool enqueue(T &);
bool dequeue(T *);
bool peek(int offset, T *);
bool isEmpty() const { return len==0; };
//int length() const { return len; };
unsigned int length() const { return (unsigned int)len; };
};
template<class T>
queue<T>::queue(int vsize) : size(vsize) {
if(size <= 0) size = 64; /* default */
data = new T[size];
head = 0;
tail = 0;
len = 0;
}
template<class T>
queue<T>::~queue() {
delete [] data;
}
template<class T>
bool
queue<T>::enqueue(T &elt) {
if(len==size) grow();
assert(len<size);
data[tail] = elt;
tail = (tail+1)%size;
len++;
return true;
}
template<class T>
bool
queue<T>::dequeue(T *elt) {
if(len>0) {
*elt = data[head];
head = (head+1)%size;
len--;
return true;
}
return false;
}
template<class T>
bool
queue<T>::peek(int offset, T *elt) {
if(len>offset) {
int pos = (head+offset)%size;
*elt = data[pos];
return true;
}
return false;
}
template<class T>
void
queue<T>::grow() {
T *data2 = new T[size*2];
int k=head;
for(int i=0; i<len; i++) {
data2[i] = data[k];
k = (k+1)%size;
}
head = 0;
tail = len;
delete [] data;
data = data2;
size *= 2;
}
#endif // QUEUE_H
|