1/*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2010, Daniel Stenberg, <daniel@haxx.se>, et al. 9 * 10 * This software is licensed as described in the file COPYING, which 11 * you should have received as part of this distribution. The terms 12 * are also available at http://curl.haxx.se/docs/copyright.html. 13 * 14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 15 * copies of the Software, and permit persons to whom the Software is 16 * furnished to do so, under the terms of the COPYING file. 17 * 18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 19 * KIND, either express or implied. 20 * 21 ***************************************************************************/ 22 23#include "setup.h" 24 25#ifdef HAVE_UNISTD_H 26# include <unistd.h> 27#endif 28 29#include "curl_gethostname.h" 30 31/* 32 * Curl_gethostname() is a wrapper around gethostname() which allows 33 * overriding the host name that the function would normally return. 34 * This capability is used by the test suite to verify exact matching 35 * of NTLM authentication, which exercises libcurl's MD4 and DES code. 36 * 37 * For libcurl debug enabled builds host name overriding takes place 38 * when environment variable CURL_GETHOSTNAME is set, using the value 39 * held by the variable to override returned host name. 40 * 41 * For libcurl shared library release builds the test suite preloads 42 * another shared library named libhostname using the LD_PRELOAD 43 * mechanism which intercepts, and might override, the gethostname() 44 * function call. In this case a given platform must support the 45 * LD_PRELOAD mechanism and additionally have environment variable 46 * CURL_GETHOSTNAME set in order to override the returned host name. 47 * 48 * For libcurl static library release builds no overriding takes place. 49 */ 50 51int Curl_gethostname(char *name, GETHOSTNAME_TYPE_ARG2 namelen) { 52 53#ifndef HAVE_GETHOSTNAME 54 55 /* Allow compilation and return failure when unavailable */ 56 (void) name; 57 (void) namelen; 58 return -1; 59 60#else 61 62#ifdef DEBUGBUILD 63 64 /* Override host name when environment variable CURL_GETHOSTNAME is set */ 65 const char *force_hostname = getenv("CURL_GETHOSTNAME"); 66 if(force_hostname) { 67 strncpy(name, force_hostname, namelen); 68 name[namelen-1] = '\0'; 69 return 0; 70 } 71 72#endif /* DEBUGBUILD */ 73 74 /* The call to system's gethostname() might get intercepted by the 75 libhostname library when libcurl is built as a non-debug shared 76 library when running the test suite. */ 77 return gethostname(name, namelen); 78 79#endif 80 81} 82