usercfg.cpp

伯克利做的SFTP安全文件传输协议

// usercfg.cpp
// implementation of usercfg.h for sftpc
// copyright SafeTP Development Group, Inc., 2000  Terms of use are as specified in license.txt

#include "usercfg.h"       // this module
#include "nonport.h"       // getCurrentUsername, ensurePath
#include "xassert.h"       // xfailure

#include <stdlib.h>        // getenv
#include <iostream.h>      // cout


string userConfigDir()
{
  // only do the full procedure once
  static string *previousVal = NULL;        // thread-safety: worst case is a one-time leak
  if (previousVal != NULL) {
    return *previousVal;
  }

  string ret;

  // ideally, the user specifies where to store config info
  // via an environment variable
  char const *envp = getenv("SAFETP_CONFIG");
  if (envp) {
    ret = envp;

    // verify the path exists; create parts as necessary
    if (!ensurePath(ret, true /*isDirectory*/)) {
      xfailure(stringb("cannot access directory " << ret <<
                       "; environment variable SAFETP_CONFIG needs to "
                       "be fixed"));
    }
  }
  else {
    // let's let /var/tmp/$user be the default; it's adequate in terms of
    // usability, and is secure
    char user[80];
    getCurrentUsername(user, 80);

    ret = stringb("/var/tmp/" << user);

    // try it
    if (!ensurePath(ret, true /*isDirectory*/)) {
      xfailure(stringb("cannot access directory " << ret <<
                       "; try setting environment variable SAFETP_CONFIG"));
    }
  }

  previousVal = new string(ret);
  return ret;
}