lib-src/memory/strpool.cc

   1 //////////////////////////////////////////////////////////////////////////////
   2 // NOTICE:
   3 //
   4 // ADLib, Prop and their related set of tools and documentation are in the
   5 // public domain.   The author(s) of this software reserve no copyrights on
   6 // the source code and any code generated using the tools.  You are encouraged
   7 // to use ADLib and Prop to develop software, in both academic and commercial
   8 // settings, and are free to incorporate any part of ADLib and Prop into
   9 // your programs.
  10 //
  11 // Although you are under no obligation to do so, we strongly recommend that
  12 // you give away all software developed using our tools.
  13 //
  14 // We also ask that credit be given to us when ADLib and/or Prop are used in
  15 // your programs, and that this notice be preserved intact in all the source
  16 // code.
  17 //
  18 // This software is still under development and we welcome any suggestions
  19 // and help from the users.
  20 //
  21 // Allen Leung
  22 // 1994
  23 //////////////////////////////////////////////////////////////////////////////
  24
  25 #include <string.h>
  26 #include <AD/memory/strpool.h>
  27
  28 //////////////////////////////////////////////////////////////////////////////
  29 // Constructor
  30 //////////////////////////////////////////////////////////////////////////////
  31 StringPool::StringPool(size_t page_size) : Mem("StringPool")
  32 {  next = limit = 0; pages = 0;
  33    pageSize = page_size;
  34    bytes_reserved = 0;
  35 }
  36
  37 StringPool::StringPool(Mem& m, size_t page_size) : Mem(m,"StringPool")
  38 {  next = limit = 0; pages = 0;
  39    pageSize = page_size;
  40    bytes_reserved = 0;
  41 }
  42
  43 //////////////////////////////////////////////////////////////////////////////
  44 // Destructor
  45 //////////////////////////////////////////////////////////////////////////////
  46 StringPool::~StringPool() { clear(); }
  47
  48 //////////////////////////////////////////////////////////////////////////////
  49 // Method to increase the size of the pool
  50 //////////////////////////////////////////////////////////////////////////////
  51 void StringPool::grow(size_t len)
  52 {  size_t size = len > pageSize ? len : pageSize;
  53    Page * newPage = (Page*)manager_mem->m_alloc(sizeof(Page) + size - 1);
  54    newPage->next = pages;
  55    pages = newPage;
  56    next = pages->data;
  57    limit = next + size;
  58    bytes_reserved += size;
  59 }
  60
  61 //////////////////////////////////////////////////////////////////////////////
  62 // Acquire a string of length $len$ from the pool and initialize it
  63 //////////////////////////////////////////////////////////////////////////////
  64 char * StringPool::operator () (const char * str, int len)
  65 {  char * newStr = (*this)[len + 1];
  66    memcpy(newStr,str,len); newStr[len] = '\0';
  67    return newStr;
  68 }
  69
  70 //////////////////////////////////////////////////////////////////////////////
  71 // Acquire a string from the pool and initialize it
  72 //////////////////////////////////////////////////////////////////////////////
  73 char * StringPool::operator [] (const char * str)
  74 {  char * newStr = (*this)[strlen(str)+1];
  75    strcpy(newStr,str);
  76    return newStr;
  77 }
  78
  79 //////////////////////////////////////////////////////////////////////////////
  80 // Mem protocol methods
  81 //////////////////////////////////////////////////////////////////////////////
  82 void StringPool::free(void *) {}
  83
  84 size_t StringPool::bytes_used() const { return bytes_reserved; }
  85
  86 //////////////////////////////////////////////////////////////////////////////
  87 // Clear the pool
  88 //////////////////////////////////////////////////////////////////////////////
  89 void StringPool::clear()
  90 {  Page * next_page;
  91    for (Page * p = pages; p; p = next_page) {
  92       next_page = p->next;
  93       manager_mem->free(p);
  94    }
  95    next = limit = 0; pages = 0;
  96 }