c++ - 从未知长度的缓冲区中读取 CString？

Question

假设我有一个文件。我将所有字节读入一个无符号字符缓冲区。从那里我试图在不知道它的长度的情况下读取一个 c 字符串(空终止)。

我尝试了以下方法:

char* Stream::ReadCString()
{
    char str[0x10000];
    int len = 0;
    char* pos = (char*)(this->buffer[this->position]);
    while(*pos != 0)
        str[len++] = *pos++;
    this->position += len+ 1;
    return str;
}

我想我可以在遍历时填充 str 数组中的每个字符，检查该字符是否以 null 终止。这是行不通的。有帮助吗？

this->buffer = 字节数组
this->position = 数组中的位置

还有其他方法吗？我想我可以通过实际缓冲区的地址来运行它:str[len++] = *(char*)(this->buffer[this->position++]) ?

更新:我的新功能:

char* Stream::ReadCString()
{
    this->AdvPosition(strlen((char*)&(this->buffer[this->position])) + 1);
    return (char*)&(this->buffer[this->position]);
}

并调用它:

printf( "String: %s\n", s.ReadCString()); //tried casting to char* as well just outputs blank string

示例文件:

Answer 1

检查这个:

#include <cstring>
#include <iostream>

class   A
{
  unsigned char buffer[4096];
  int   position;

public:
  A() : position(0)
  {
    memset(buffer, 0, 4096);
    char        *pos = reinterpret_cast<char*>(&(this->buffer[50]));
    strcpy(pos, "String");
    pos = reinterpret_cast<char*>(&(this->buffer[100]));
    strcpy(pos, "An other string");
  }

   const char *ReadString()
  {
    if (this->position != 4096)
      {
        while (std::isalpha(this->buffer[this->position]) == false && this->position != 4096)
               this->position++;
        if (this->position == 4096)
          return 0;
        void    *tmp = &(this->buffer[this->position]);
        char    *str  = static_cast<char *>(tmp);
        this->position += strlen(str);
        return (str);
      }
    return 0;
  }

};

reintrepret_cast 仅用于初始化，因为您正在从文件中读取

int     main()
{
  A     test;

  std::cout << test.ReadString() << std::endl;
  std::cout << test.ReadString() << std::endl;
  std::cout << test.ReadString() << std::endl;
}

http://ideone.com/LcPdFD

编辑我已经改完 ReadString()