Java example source code file (bytes.h)

This example Java source code file (bytes.h) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

bytes_of, product, ptrlist_qsort, win32_lean_and_mean

The bytes.h Java example source code

/*
 * Copyright (c) 2001, 2008, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

#ifdef WIN32_LEAN_AND_MEAN
typedef signed char byte ;
#endif

struct bytes {
  byte*  ptr;
  size_t len;
  byte*  limit() { return ptr+len; }

  void set(byte* ptr_, size_t len_) { ptr = ptr_; len = len_; }
  void set(const char* str)         { ptr = (byte*)str; len = strlen(str); }
  bool inBounds(const void* p);     // p in [ptr, limit)
  void malloc(size_t len_);
  void realloc(size_t len_);
  void free();
  void copyFrom(const void* ptr_, size_t len_, size_t offset = 0);
  void saveFrom(const void* ptr_, size_t len_);
  void saveFrom(const char* str) { saveFrom(str, strlen(str)); }
  void copyFrom(bytes& other, size_t offset = 0) {
    copyFrom(other.ptr, other.len, offset);
  }
  void saveFrom(bytes& other) {
    saveFrom(other.ptr, other.len);
  }
  void clear(int fill_byte = 0) { memset(ptr, fill_byte, len); }
  byte* writeTo(byte* bp);
  bool equals(bytes& other) { return 0 == compareTo(other); }
  int compareTo(bytes& other);
  bool contains(byte c) { return indexOf(c) >= 0; }
  int indexOf(byte c);
  // substrings:
  static bytes of(byte* ptr, size_t len) {
    bytes res;
    res.set(ptr, len);
    return res;
  }
  bytes slice(size_t beg, size_t end) {
    bytes res;
    res.ptr = ptr + beg;
    res.len = end - beg;
    assert(res.len == 0 || inBounds(res.ptr) && inBounds(res.limit()-1));
    return res;
  }
  // building C strings inside byte buffers:
  bytes& strcat(const char* str) { ::strcat((char*)ptr, str); return *this; }
  bytes& strcat(bytes& other) { ::strncat((char*)ptr, (char*)other.ptr, other.len); return *this; }
  char* strval() { assert(strlen((char*)ptr) == len); return (char*) ptr; }
#ifdef PRODUCT
  const char* string() { return 0; }
#else
  const char* string();
#endif
};
#define BYTES_OF(var) (bytes::of((byte*)&(var), sizeof(var)))

struct fillbytes {
  bytes b;
  size_t allocated;

  byte*  base()               { return b.ptr; }
  size_t size()               { return b.len; }
  byte*  limit()              { return b.limit(); }          // logical limit
  void   setLimit(byte* lp)   { assert(isAllocated(lp)); b.len = lp - b.ptr; }
  byte*  end()                { return b.ptr + allocated; }  // physical limit
  byte*  loc(size_t o)        { assert(o < b.len); return b.ptr + o; }
  void   init()               { allocated = 0; b.set(null, 0); }
  void   init(size_t s)       { init(); ensureSize(s); }
  void   free()               { if (allocated != 0) b.free(); allocated = 0; }
  void   empty()              { b.len = 0; }
  byte*  grow(size_t s);      // grow so that limit() += s
  int    getByte(uint i)      { return *loc(i) & 0xFF; }
  void   addByte(byte x)      { *grow(1) = x; }
  void   ensureSize(size_t s); // make sure allocated >= s
  void   trimToSize()         { if (allocated > size())  b.realloc(allocated = size()); }
  bool   canAppend(size_t s)  { return allocated > b.len+s; }
  bool   isAllocated(byte* p) { return p >= base() && p <= end(); } //asserts
  void   set(bytes& src)      { set(src.ptr, src.len); }

  void set(byte* ptr, size_t len) {
    b.set(ptr, len);
    allocated = 0;   // mark as not reallocatable
  }

  // block operations on resizing byte buffer:
  fillbytes& append(const void* ptr_, size_t len_)
    { memcpy(grow(len_), ptr_, len_); return (*this); }
  fillbytes& append(bytes& other)
    { return append(other.ptr, other.len); }
  fillbytes& append(const char* str)
    { return append(str, strlen(str)); }
};

struct ptrlist : fillbytes {
  typedef const void* cvptr;
  int    length()     { return (int)(size() / sizeof(cvptr)); }
  cvptr* base()       { return (cvptr*) fillbytes::base(); }
  cvptr& get(int i)   { return *(cvptr*)loc(i * sizeof(cvptr)); }
  cvptr* limit()      { return (cvptr*) fillbytes::limit(); }
  void   add(cvptr x) { *(cvptr*)grow(sizeof(x)) = x; }
  void   popTo(int l) { assert(l <= length()); b.len = l * sizeof(cvptr); }
  int    indexOf(cvptr x);
  bool   contains(cvptr x) { return indexOf(x) >= 0; }
  void   freeAll();   // frees every ptr on the list, plus the list itself
};
// Use a macro rather than mess with subtle mismatches
// between member and non-member function pointers.
#define PTRLIST_QSORT(ptrls, fn) \
  ::qsort((ptrls).base(), (ptrls).length(), sizeof(void*), fn)

struct intlist : fillbytes {
  int    length()     { return (int)(size() / sizeof(int)); }
  int*   base()       { return (int*) fillbytes::base(); }
  int&   get(int i)   { return *(int*)loc(i * sizeof(int)); }
  int*   limit()      { return (int*) fillbytes::limit(); }
  void   add(int x)   { *(int*)grow(sizeof(x)) = x; }
  void   popTo(int l) { assert(l <= length()); b.len = l * sizeof(int); }
  int    indexOf(int x);
  bool   contains(int x) { return indexOf(x) >= 0; }
};