text: /*
   * Copyright (c) 2016 Ambroz Bizjak
   * All rights reserved.
   * 
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
   * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef APRINTER_MEMREF_H
  #define APRINTER_MEMREF_H
  
  #include <stddef.h>
  #include <string.h>
  
  #include <aprinter/base/Assert.h>
  
  namespace APrinter {
  
  struct MemRef {
      char const *ptr;
      size_t len;
      
      MemRef () = default;
      
      inline MemRef (char const *ptr_arg, size_t len_arg)
      : ptr(ptr_arg), len(len_arg)
      {
      }
      
      inline MemRef (char const *cstr)
      : ptr(cstr), len(strlen(cstr))
      {
      }
      
      inline static MemRef Null ()
      {
          return MemRef(nullptr, 0);
      }
      
      inline char at (size_t pos) const
      {
          AMBRO_ASSERT(ptr)
          AMBRO_ASSERT(pos < len)
          
          return ptr[pos];
      }
      
      inline MemRef subFrom (size_t offset) const
      {
          AMBRO_ASSERT(ptr)
          AMBRO_ASSERT(offset <= len)
          
          return MemRef(ptr + offset, len - offset);
      }
      
      inline MemRef subTo (size_t offset) const
      {
          AMBRO_ASSERT(ptr)
          AMBRO_ASSERT(offset <= len)
          
          return MemRef(ptr, offset);
      }
      
      inline bool equalTo (MemRef other) const
      {
          AMBRO_ASSERT(ptr)
          AMBRO_ASSERT(other.ptr)
          
          return len == other.len && !memcmp(ptr, other.ptr, len);
      }
      
      bool removePrefix (char const *prefix)
      {
          size_t pos = 0;
          while (prefix[pos] != '\0') {
              if (pos == len || ptr[pos] != prefix[pos]) {
                  return false;
              }
              pos++;
          }
          *this = subFrom(pos);
          return true;
      }
  };
  
  }
  
  #endif
  