urldata.h

#ifndef __URLDATA_H
#define __URLDATA_H
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id$
 ***************************************************************************/

/* This file is for lib internal stuff */

#include "setup.h"

#define PORT_FTP 21
#define PORT_FTPS 990
#define PORT_TELNET 23
#define PORT_HTTP 80
#define PORT_HTTPS 443
#define PORT_DICT 2628
#define PORT_LDAP 389
#define PORT_LDAPS 636
#define PORT_TFTP 69
#define PORT_SSH 22

#define DICT_MATCH "/MATCH:"
#define DICT_MATCH2 "/M:"
#define DICT_MATCH3 "/FIND:"
#define DICT_DEFINE "/DEFINE:"
#define DICT_DEFINE2 "/D:"
#define DICT_DEFINE3 "/LOOKUP:"

#define CURL_DEFAULT_USER "anonymous"
#define CURL_DEFAULT_PASSWORD "ftp@example.com"

#include "cookie.h"
#include "formdata.h"

#ifdef USE_SSLEAY
#ifdef USE_OPENSSL
#include "openssl/rsa.h"
#include "openssl/crypto.h"
#include "openssl/x509.h"
#include "openssl/pem.h"
#include "openssl/ssl.h"
#include "openssl/err.h"
#ifdef HAVE_OPENSSL_ENGINE_H
#include <openssl/engine.h>
#endif
#ifdef HAVE_OPENSSL_PKCS12_H
#include <openssl/pkcs12.h>
#endif
#else /* SSLeay-style includes */
#include "rsa.h"
#include "crypto.h"
#include "x509.h"
#include "pem.h"
#include "ssl.h"
#include "err.h"
#endif /* USE_OPENSSL */
#ifdef USE_GNUTLS
#error Configuration error; cannot use GnuTLS *and* OpenSSL.
#endif
#endif /* USE_SSLEAY */

#ifdef USE_GNUTLS
#include <gnutls/gnutls.h>
#endif

#ifdef USE_NSS
#include <nspr.h>
#endif

#ifdef USE_QSOSSL
#include <qsossl.h>
#endif

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#include "timeval.h"

#ifdef HAVE_ZLIB_H
#include <zlib.h>               /* for content-encoding */
#endif

#ifdef USE_ARES
#include <ares.h>
#endif

#include <curl/curl.h>

#include "http_chunks.h" /* for the structs and enum stuff */
#include "hostip.h"
#include "hash.h"
#include "splay.h"

#ifdef HAVE_GSSAPI
# ifdef HAVE_GSSGNU
#  include <gss.h>
# elif defined HAVE_GSSMIT
#  include <gssapi/gssapi.h>
#  include <gssapi/gssapi_generic.h>
# else
#  include <gssapi.h>
# endif
#endif

#ifdef HAVE_LIBSSH2_H
#include <libssh2.h>
#include <libssh2_sftp.h>
#endif /* HAVE_LIBSSH2_H */

/* Download buffer size, keep it fairly big for speed reasons */
#undef BUFSIZE
#define BUFSIZE CURL_MAX_WRITE_SIZE

/* Initial size of the buffer to store headers in, it'll be enlarged in case
   of need. */
#define HEADERSIZE 256

#define CURLEASY_MAGIC_NUMBER 0xc0dedbadU

/* Just a convenience macro to get the larger value out of two given.
   We prefix with CURL to prevent name collisions. */
#define CURLMAX(x,y) ((x)>(y)?(x):(y))

#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
/* Types needed for krb4/5-ftp connections */
struct krb4buffer {
  void *data;
  size_t size;
  size_t index;
  int eof_flag;
};
enum protection_level {
  prot_clear,
  prot_safe,
  prot_confidential,
  prot_private,
  prot_cmd
};
#endif

/* enum for the nonblocking SSL connection state machine */
typedef enum {
  ssl_connect_1,
  ssl_connect_2,
  ssl_connect_2_reading,
  ssl_connect_2_writing,
  ssl_connect_3,
  ssl_connect_done
} ssl_connect_state;

/* struct for data related to each SSL connection */
struct ssl_connect_data {
  bool use;        /* use ssl encrypted communications TRUE/FALSE, not
                      necessarily using it atm but at least asked to or
                      meaning to use it */
#ifdef USE_SSLEAY
  /* these ones requires specific SSL-types */
  SSL_CTX* ctx;
  SSL*     handle;
  X509*    server_cert;
  ssl_connect_state connecting_state;
#endif /* USE_SSLEAY */
#ifdef USE_GNUTLS
  gnutls_session session;
  gnutls_certificate_credentials cred;
#endif /* USE_GNUTLS */
#ifdef USE_NSS
  PRFileDesc *handle;
  char *client_nickname;
#endif /* USE_NSS */
#ifdef USE_QSOSSL
  SSLHandle *handle;
#endif /* USE_QSOSSL */
};

struct ssl_config_data {
  long version;          /* what version the client wants to use */
  long certverifyresult; /* result from the certificate verification */
  long verifypeer;       /* set TRUE if this is desired */
  long verifyhost;       /* 0: no verify
                            1: check that CN exists
                            2: CN must match hostname */
  char *CApath;          /* certificate dir (doesn't work on windows) */
  char *CAfile;          /* cerficate to verify peer against */
  char *random_file;     /* path to file containing "random" data */
  char *egdsocket;       /* path to file containing the EGD daemon socket */
  char *cipher_list;     /* list of ciphers to use */
  long numsessions;      /* SSL session id cache size */
  curl_ssl_ctx_callback fsslctx; /* function to initialize ssl ctx */
  void *fsslctxp;        /* parameter for call back */
  bool sessionid;        /* cache session IDs or not */
};

/* information stored about one single SSL session */
struct curl_ssl_session {
  char *name;       /* host name for which this ID was used */
  void *sessionid;  /* as returned from the SSL layer */
  size_t idsize;    /* if known, otherwise 0 */
  long age;         /* just a number, the higher the more recent */
  unsigned short remote_port; /* remote port to connect to */
  struct ssl_config_data ssl_config; /* setup for this session */
};

/* Struct used for Digest challenge-response authentication */
struct digestdata {
  char *nonce;
  char *cnonce;
  char *realm;
  int algo;
  bool stale; /* set true for re-negotiation */
  char *opaque;
  char *qop;
  char *algorithm;
  int nc; /* nounce count */
};

typedef enum {
  NTLMSTATE_NONE,
  NTLMSTATE_TYPE1,
  NTLMSTATE_TYPE2,
  NTLMSTATE_TYPE3,
  NTLMSTATE_LAST
} curlntlm;

#ifdef USE_WINDOWS_SSPI
/* When including these headers, you must define either SECURITY_WIN32
 * or SECURITY_KERNEL, indicating who is compiling the code.
 */
#define SECURITY_WIN32 1
#include <security.h>
#include <sspi.h>
#include <rpc.h>
#endif

#if defined(CURL_DOES_CONVERSIONS) && defined(HAVE_ICONV)
#include <iconv.h>
#endif

/* Struct used for NTLM challenge-response authentication */
struct ntlmdata {
  curlntlm state;
#ifdef USE_WINDOWS_SSPI
  CredHandle handle;
  CtxtHandle c_handle;
  SEC_WINNT_AUTH_IDENTITY identity;
  SEC_WINNT_AUTH_IDENTITY *p_identity;
  int has_handles;
  void *type_2;
  int n_type_2;
#else
  unsigned int flags;
  unsigned char nonce[8];
#endif
};

#ifdef HAVE_GSSAPI
struct negotiatedata {
  bool gss; /* Whether we're processing GSS-Negotiate or Negotiate */
  const char* protocol; /* "GSS-Negotiate" or "Negotiate" */
  OM_uint32 status;
  gss_ctx_id_t context;
  gss_name_t server_name;
  gss_buffer_desc output_token;
};
#endif

/****************************************************************************
 * HTTP unique setup
 ***************************************************************************/
struct HTTP {
  struct FormData *sendit;
  curl_off_t postsize; /* off_t to handle large file sizes */
  char *postdata;

  const char *p_pragma;      /* Pragma: string */
  const char *p_accept;      /* Accept: string */
  curl_off_t readbytecount;
  curl_off_t writebytecount;

  /* For FORM posting */
  struct Form form;

  struct back {
    curl_read_callback fread_func; /* backup storage for fread pointer */
    void *fread_in;           /* backup storage for fread_in pointer */
    char *postdata;
    curl_off_t postsize;
  } backup;

  enum {
    HTTPSEND_NADA,    /* init */
    HTTPSEND_REQUEST, /* sending a request */
    HTTPSEND_BODY,    /* sending body */
    HTTPSEND_LAST     /* never use this */
  } sending;

  void *send_buffer; /* used if the request couldn't be sent in one chunk,
                        points to an allocated send_buffer struct */
};

/****************************************************************************
 * FTP unique setup
 ***************************************************************************/
typedef enum {
  FTP_STOP,    /* do nothing state, stops the state machine */
  FTP_WAIT220, /* waiting for the initial 220 response immediately after
                  a connect */
  FTP_AUTH,
  FTP_USER,
  FTP_PASS,
  FTP_ACCT,
  FTP_PBSZ,
  FTP_PROT,
  FTP_CCC,
  FTP_PWD,
  FTP_QUOTE, /* waiting for a response to a command sent in a quote list */
  FTP_RETR_PREQUOTE,
  FTP_STOR_PREQUOTE,
  FTP_POSTQUOTE,
  FTP_CWD,  /* change dir */
  FTP_MKD,  /* if the dir didn't exist */
  FTP_MDTM, /* to figure out the datestamp */
  FTP_TYPE, /* to set type when doing a head-like request */
  FTP_LIST_TYPE, /* set type when about to do a dir list */
  FTP_RETR_TYPE, /* set type when about to RETR a file */
  FTP_STOR_TYPE, /* set type when about to STOR a file */
  FTP_SIZE, /* get the remote file's size for head-like request */
  FTP_RETR_SIZE, /* get the remote file's size for RETR */
  FTP_STOR_SIZE, /* get the size for (resumed) STOR */
  FTP_REST, /* when used to check if the server supports it in head-like */
  FTP_RETR_REST, /* when asking for "resume" in for RETR */
  FTP_PORT, /* generic state for PORT, LPRT and EPRT, check count1 */
  FTP_PASV, /* generic state for PASV and EPSV, check count1 */
  FTP_LIST, /* generic state for LIST, NLST or a custom list command */
  FTP_RETR,
  FTP_STOR, /* generic state for STOR and APPE */
  FTP_QUIT,
  FTP_LAST  /* never used */
} ftpstate;

typedef enum {
  FTPFILE_MULTICWD  = 1, /* as defined by RFC1738 */
  FTPFILE_NOCWD     = 2, /* use SIZE / RETR / STOR on the full path */
  FTPFILE_SINGLECWD = 3  /* make one CWD, then SIZE / RETR / STOR on the file */
} curl_ftpfile;

typedef enum {
  FTPTRANSFER_BODY, /* yes do transfer a body */
  FTPTRANSFER_INFO, /* do still go through to get info/headers */
  FTPTRANSFER_NONE, /* don't get anything and don't get info */
  FTPTRANSFER_LAST  /* end of list marker, never used */
} curl_ftptransfer;

/* This FTP struct is used in the SessionHandle. All FTP data that is
   connection-oriented must be in FTP_conn to properly deal with the fact that
   perhaps the SessionHandle is changed between the times the connection is
   used. */
struct FTP {
  curl_off_t *bytecountp;
  char *user;    /* user name string */
  char *passwd;  /* password string */

  /* transfer a file/body or not, done as a typedefed enum just to make
     debuggers display the full symbol and not just the numerical value */
  curl_ftptransfer transfer;
  curl_off_t downloadsize;
};

/* ftp_conn is used for striuct connection-oriented data in the connectdata
   struct */
struct ftp_conn {
  char *entrypath; /* the PWD reply when we logged on */
  char **dirs;   /* realloc()ed array for path components */
  int dirdepth;  /* number of entries used in the 'dirs' array */
  int diralloc;  /* number of entries allocated for the 'dirs' array */
  char *file;    /* decoded file */
  char *cache;       /* data cache between getresponse()-calls */
  curl_off_t cache_size; /* size of cache in bytes */
  bool dont_check;  /* Set to TRUE to prevent the final (post-transfer)
                       file size and 226/250 status check. It should still
                       read the line, just ignore the result. */
  long response_time; /* When no timeout is given, this is the amount of
                         seconds we await for an FTP response. Initialized
                         in Curl_ftp_connect() */
  bool ctl_valid;   /* Tells Curl_ftp_quit() whether or not to do anything. If
                       the connection has timed out or been closed, this
                       should be FALSE when it gets to Curl_ftp_quit() */
  bool cwddone;     /* if it has been determined that the proper CWD combo
                       already has been done */
  bool cwdfail;     /* set TRUE if a CWD command fails, as then we must prevent
                       caching the current directory */
  char *prevpath;   /* conn->path from the previous transfer */
  char transfertype; /* set by ftp_transfertype for use by Curl_client_write()a
                        and others (A/I or zero) */
  size_t nread_resp; /* number of bytes currently read of a server response */
  char *linestart_resp; /* line start pointer for the FTP server response
                           reader function */

  int count1; /* general purpose counter for the state machine */
  int count2; /* general purpose counter for the state machine */
  int count3; /* general purpose counter for the state machine */
  char *sendthis; /* allocated pointer to a buffer that is to be sent to the
                     ftp server */
  size_t sendleft; /* number of bytes left to send from the sendthis buffer */
  size_t sendsize; /* total size of the sendthis buffer */
  struct timeval response; /* set to Curl_tvnow() when a command has been sent
                              off, used to time-out response reading */
  ftpstate state; /* always use ftp.c:state() to change state! */
};

/****************************************************************************
 * SSH unique setup
 ***************************************************************************/
typedef enum {
  SSH_NO_STATE = -1,  /* Used for "nextState" so say there is none */
  SSH_STOP = 0,       /* do nothing state, stops the state machine */

  SSH_S_STARTUP,      /* Session startup, First state in SSH-CONNECT */
  SSH_AUTHLIST,
  SSH_AUTH_PKEY_INIT,
  SSH_AUTH_PKEY,
  SSH_AUTH_PASS_INIT,
  SSH_AUTH_PASS,
  SSH_AUTH_HOST_INIT,
  SSH_AUTH_HOST,
  SSH_AUTH_KEY_INIT,
  SSH_AUTH_KEY,
  SSH_AUTH_DONE,
  SSH_SFTP_INIT,
  SSH_SFTP_REALPATH,   /* Last state in SSH-CONNECT */

  SSH_SFTP_QUOTE_INIT, /* First state in SFTP-DO */
  SSH_SFTP_POSTQUOTE_INIT, /* (Possibly) First state in SFTP-DONE */
  SSH_SFTP_QUOTE,
  SSH_SFTP_NEXT_QUOTE,
  SSH_SFTP_QUOTE_STAT,
  SSH_SFTP_QUOTE_SETSTAT,
  SSH_SFTP_QUOTE_SYMLINK,
  SSH_SFTP_QUOTE_MKDIR,
  SSH_SFTP_QUOTE_RENAME,
  SSH_SFTP_QUOTE_RMDIR,
  SSH_SFTP_QUOTE_UNLINK,
  SSH_SFTP_TRANS_INIT,
  SSH_SFTP_UPLOAD_INIT,
  SSH_SFTP_CREATE_DIRS_INIT,
  SSH_SFTP_CREATE_DIRS,
  SSH_SFTP_CREATE_DIRS_MKDIR,
  SSH_SFTP_READDIR_INIT,
  SSH_SFTP_READDIR,
  SSH_SFTP_READDIR_LINK,
  SSH_SFTP_READDIR_BOTTOM,
  SSH_SFTP_READDIR_DONE,
  SSH_SFTP_DOWNLOAD_INIT,
  SSH_SFTP_DOWNLOAD_STAT, /* Last state in SFTP-DO */
  SSH_SFTP_CLOSE,    /* Last state in SFTP-DONE */
  SSH_SFTP_SHUTDOWN, /* First state in SFTP-DISCONNECT */
  SSH_SCP_TRANS_INIT, /* First state in SCP-DO */
  SSH_SCP_UPLOAD_INIT,
  SSH_SCP_DOWNLOAD_INIT,
  SSH_SCP_DONE,
  SSH_SCP_SEND_EOF,
  SSH_SCP_WAIT_EOF,
  SSH_SCP_WAIT_CLOSE,
  SSH_SCP_CHANNEL_FREE,   /* Last state in SCP-DONE */
  SSH_SESSION_DISCONNECT, /* First state in SCP-DISCONNECT */
  SSH_SESSION_FREE,       /* Last state in SCP/SFTP-DISCONNECT */
  SSH_QUIT,
  SSH_LAST  /* never used */
} sshstate;

/* this struct is used in the HandleData struct which is part of the
   SessionHandle, which means this is used on a per-easy handle basis.
   Everything that is strictly related to a connection is banned from this
   struct. */
struct SSHPROTO {
  char *path;                   /* the path we operate on */
};

/* ssh_conn is used for struct connection-oriented data in the connectdata
   struct */
struct ssh_conn {
  const char *authlist;       /* List of auth. methods, managed by libssh2 */
#ifdef USE_LIBSSH2
  const char *passphrase;     /* passphrase to use */
  char *rsa_pub;              /* path name */
  char *rsa;                  /* path name */
  bool authed;                /* the connection has been authenticated fine */
  sshstate state;             /* always use ssh.c:state() to change state! */
  sshstate nextstate;         /* the state to goto after stopping */
  CURLcode actualcode;        /* the actual error code */
  struct curl_slist *quote_item; /* for the quote option */
  char *quote_path1;          /* two generic pointers for the QUOTE stuff */
  char *quote_path2;
  LIBSSH2_SFTP_ATTRIBUTES quote_attrs; /* used by the SFTP_QUOTE state */
  char *homedir;              /* when doing SFTP we figure out home dir in the
                                 connect phase */

  /* Here's a set of struct members used by the SFTP_READDIR state */
  LIBSSH2_SFTP_ATTRIBUTES readdir_attrs;
  char *readdir_filename;
  char *readdir_longentry;
  int readdir_len, readdir_totalLen, readdir_currLen;
  char *readdir_line;
  char *readdir_linkPath;
  /* end of READDIR stuff */

  int secondCreateDirs;         /* counter use by the code to see if the
                                   second attempt has been made to change
                                   to/create a directory */
  char *slash_pos;              /* used by the SFTP_CREATE_DIRS state */
  LIBSSH2_SESSION *ssh_session; /* Secure Shell session */
  LIBSSH2_CHANNEL *ssh_channel; /* Secure Shell channel handle */
  LIBSSH2_SFTP *sftp_session;   /* SFTP handle */
  LIBSSH2_SFTP_HANDLE *sftp_handle;
#endif /* USE_LIBSSH2 */
};


/****************************************************************************
 * FILE unique setup
 ***************************************************************************/
struct FILEPROTO {
  char *path; /* the path we operate on */
  char *freepath; /* pointer to the allocated block we must free, this might
                     differ from the 'path' pointer */
  int fd;     /* open file descriptor to read from! */
};

/*
 * Boolean values that concerns this connection.
 */
struct ConnectBits {
  bool close; /* if set, we close the connection after this request */
  bool reuse; /* if set, this is a re-used connection */
  bool chunk; /* if set, this is a chunked transfer-encoding */
  bool proxy; /* if set, this transfer is done through a proxy - any type */
  bool httpproxy;    /* if set, this transfer is done through a http proxy */
  bool user_passwd;    /* do we use user+password for this connection? */
  bool proxy_user_passwd; /* user+password for the proxy? */
  bool ipv6_ip; /* we communicate with a remote site specified with pure IPv6
                   IP address */
  bool ipv6;    /* we communicate with a site using an IPv6 address */

  bool do_more; /* this is set TRUE if the ->curl_do_more() function is
                   supposed to be called, after ->curl_do() */

  bool upload_chunky; /* set TRUE if we are doing chunked transfer-encoding
                         on upload */
  bool getheader;     /* TRUE if header parsing is wanted */

  bool forbidchunk;   /* used only to explicitly forbid chunk-upload for
                         specific upload buffers. See readmoredata() in
                         http.c for details. */

  bool tcpconnect;    /* the TCP layer (or simimlar) is connected, this is set
                         the first time on the first connect function call */
  bool protoconnstart;/* the protocol layer has STARTED its operation after
                         the TCP layer connect */

  bool retry;         /* this connection is about to get closed and then
                         re-attempted at another connection. */
  bool no_body;       /* CURLOPT_NO_BODY (or similar) was set */
  bool tunnel_proxy;  /* if CONNECT is used to "tunnel" through the proxy.
                         This is implicit when SSL-protocols are used through
                         proxies, but can also be enabled explicitly by
                         apps */
  bool tunnel_connecting; /* TRUE while we're still waiting for a proxy CONNECT
                           */
  bool authneg;       /* TRUE when the auth phase has started, which means
                         that we are creating a request with an auth header,
                         but it is not the final request in the auth
                         negotiation. */
  bool rewindaftersend;/* TRUE when the sending couldn't be stopped even
                          though it will be discarded. When the whole send
                          operation is done, we must call the data rewind
                          callback. */
  bool ftp_use_epsv;  /* As set with CURLOPT_FTP_USE_EPSV, but if we find out
                         EPSV doesn't work we disable it for the forthcoming
                         requests */

  bool ftp_use_eprt;  /* As set with CURLOPT_FTP_USE_EPRT, but if we find out
                         EPRT doesn't work we disable it for the forthcoming
                         requests */
  bool netrc;         /* name+password provided by netrc */

  bool trailerhdrpresent; /* Set when Trailer: header found in HTTP response.
                             Required to determine whether to look for trailers
                             in case of Transfer-Encoding: chunking */
  bool done;          /* set to FALSE when Curl_do() is called and set to TRUE
                         when Curl_done() is called, to prevent Curl_done() to
                         get invoked twice when the multi interface is
                         used. */
  bool stream_was_rewound; /* Indicates that the stream was rewound after a
                              request read past the end of its response byte
                              boundary */
  bool proxy_connect_closed; /* set true if a proxy disconnected the
                                connection in a CONNECT request with auth, so
                                that libcurl should reconnect and continue. */
  bool bound; /* set true if bind() has already been done on this socket/
                 connection */
};

struct hostname {
  char *rawalloc; /* allocated "raw" version of the name */
  char *encalloc; /* allocated IDN-encoded version of the name */
  char *name;     /* name to use internally, might be encoded, might be raw */
  char *dispname; /* name to display, as 'name' might be encoded */
};

/*
 * Flags on the keepon member of the Curl_transfer_keeper
 */

#define KEEP_NONE  0
#define KEEP_READ  (1<<0)     /* there is or may be data to read */
#define KEEP_WRITE (1<<1)     /* there is or may be data to write */
#define KEEP_READ_HOLD (1<<2) /* when set, no reading should be done but there
                                 might still be data to read */
#define KEEP_WRITE_HOLD (1<<3) /* when set, no writing should be done but there
                                  might still be data to write */
#define KEEP_READ_PAUSE (1<<4) /* reading is paused */
#define KEEP_WRITE_PAUSE (1<<5) /* writing is paused */

#define KEEP_READBITS (KEEP_READ | KEEP_READ_HOLD | KEEP_READ_PAUSE)
#define KEEP_WRITEBITS (KEEP_WRITE | KEEP_WRITE_HOLD | KEEP_WRITE_PAUSE)


#ifdef HAVE_LIBZ
typedef enum {
  ZLIB_UNINIT,          /* uninitialized */
  ZLIB_INIT,            /* initialized */
  ZLIB_GZIP_HEADER,     /* reading gzip header */
  ZLIB_GZIP_INFLATING,  /* inflating gzip stream */
  ZLIB_INIT_GZIP        /* initialized in transparent gzip mode */
} zlibInitState;
#endif

#if defined(USE_ARES) || defined(USE_THREADING_GETHOSTBYNAME) || \
    defined(USE_THREADING_GETADDRINFO)
struct Curl_async {
  char *hostname;
  int port;
  struct Curl_dns_entry *dns;
  bool done;  /* set TRUE when the lookup is complete */
  int status; /* if done is TRUE, this is the status from the callback */
  void *os_specific;  /* 'struct thread_data' for Windows */
};
#endif

#define FIRSTSOCKET     0
#define SECONDARYSOCKET 1

/* These function pointer types are here only to allow easier typecasting
   within the source when we need to cast between data pointers (such as NULL)
   and function pointers. */
typedef CURLcode (*Curl_do_more_func)(struct connectdata *);
typedef CURLcode (*Curl_done_func)(struct connectdata *, CURLcode, bool);


/*
 * Request specific data in the easy handle (SessionHandle).  Previously,
 * these members were on the connectdata struct but since a conn struct may
 * now be shared between different SessionHandles, we store connection-specifc
 * data here. This struct only keeps stuff that's interesting for *this*
 * request, as it will be cleared between multiple ones
 */
struct SingleRequest {
  curl_off_t size;        /* -1 if unknown at this point */
  curl_off_t *bytecountp; /* return number of bytes read or NULL */

  curl_off_t maxdownload; /* in bytes, the maximum amount of data to fetch,
                             -1 means unlimited */
  curl_off_t *writebytecountp; /* return number of bytes written or NULL */

  curl_off_t bytecount;         /* total number of bytes read */
  curl_off_t writebytecount;    /* number of bytes written */

  long headerbytecount;         /* only count received headers */
  long deductheadercount; /* this amount of bytes doesn't count when we check
                             if anything has been transfered at the end of a
                             connection. We use this counter to make only a
                             100 reply (without a following second response
                             code) result in a CURLE_GOT_NOTHING error code */

  struct timeval start;         /* transfer started at this time */
  struct timeval now;           /* current time */
  bool header;                  /* incoming data has HTTP header */
  enum {
    HEADER_NORMAL,              /* no bad header at all */
    HEADER_PARTHEADER,          /* part of the chunk is a bad header, the rest
                                   is normal data */
    HEADER_ALLBAD               /* all was believed to be header */
  } badheader;                  /* the header was deemed bad and will be
                                   written as body */
  int headerline;               /* counts header lines to better track the
                                   first one */
  char *hbufp;                  /* points at *end* of header line */
  size_t hbuflen;
  char *str;                    /* within buf */
  char *str_start;              /* within buf */
  char *end_ptr;                /* within buf */
  char *p;                      /* within headerbuff */
  bool content_range;           /* set TRUE if Content-Range: was found */
  curl_off_t offset;            /* possible resume offset read from the
                                   Content-Range: header */
  int httpcode;                 /* error code from the 'HTTP/1.? XXX' line */
  int httpversion;              /* the HTTP version*10 */
  struct timeval start100;      /* time stamp to wait for the 100 code from */
  bool write_after_100_header;  /* TRUE = we enable the write after we
                                   received a 100-continue/timeout or
                                   FALSE = directly */
  bool wait100_after_headers;   /* TRUE = after the request-headers have been
                                   sent off properly, we go into the wait100
                                   state, FALSE = don't */
  int content_encoding;         /* What content encoding. sec 3.5, RFC2616. */

#define IDENTITY 0              /* No encoding */
#define DEFLATE 1               /* zlib delfate [RFC 1950 & 1951] */
#define GZIP 2                  /* gzip algorithm [RFC 1952] */
#define COMPRESS 3              /* Not handled, added for completeness */

#ifdef HAVE_LIBZ
  zlibInitState zlib_init;      /* possible zlib init state;
                                   undefined if Content-Encoding header. */
  z_stream z;                   /* State structure for zlib. */
#endif

  time_t timeofdoc;
  long bodywrites;

  char *buf;
  char *uploadbuf;
  curl_socket_t maxfd;

  int keepon;

  bool upload_done; /* set to TRUE when doing chunked transfer-encoding upload
                       and we're uploading the last chunk */

  bool ignorebody;  /* we read a response-body but we ignore it! */
  bool ignorecl;    /* This HTTP response has no body so we ignore the Content-
                       Length: header */

  char *newurl; /* This can only be set if a Location: was in the
                   document headers */

  /* 'upload_present' is used to keep a byte counter of how much data there is
     still left in the buffer, aimed for upload. */
  ssize_t upload_present;

   /* 'upload_fromhere' is used as a read-pointer when we uploaded parts of a
      buffer, so the next read should read from where this pointer points to,
      and the 'upload_present' contains the number of bytes available at this
      position */
  char *upload_fromhere;
};