strtokp.cpp

来自「伯克利做的SFTP安全文件传输协议」· C++ 代码 · 共 80 行

// strtokp.cc
// code for strtokp.h
// copyright SafeTP Development Group, Inc., 2000  Terms of use are as specified in license.txt

#include "strtokp.h"    // this module
#include "exc.h"        // xassert
#include <string.h>     // strtok


StrtokParse::StrtokParse(char const *str, char const *delim)
{
  xassert(str != NULL);

  // make local copy
  buf = str;

  // parse it first time to count # of tokens
  int ct=0;
  char *tok = strtok(buf.pchar(), delim);
  while (tok) {
    ct++;
    tok = strtok(NULL, delim);
  }

  // restore buf
  buf = str;

  // allocate storage
  _tokc = ct;
  if (ct) {
    _tokv = new char*[ct+1];
    _tokv[ct] = NULL;     // terminate argv[]-like list
  }
  else {
    _tokv = NULL;
  }

  // parse it again, this time saving the values
  ct=0;
  tok = strtok(buf.pchar(), delim);
  while (tok) {
    _tokv[ct] = tok;
    ct++;
    tok = strtok(NULL, delim);
  }

  // simple check just because it's easy
  xassert(ct == _tokc);
}


StrtokParse::~StrtokParse()
{
  // buf deletes itself

  if (_tokv) {
    delete _tokv;
  }
}


void StrtokParse::validate(int which) const
{
  xassert((unsigned)which < (unsigned)_tokc);
}


char const *StrtokParse::tokv(int which) const
{
  validate(which);
  return _tokv[which];
}


int StrtokParse::offset(int which) const
{
  return tokv(which) - (char const*)buf;
}