nmap/nsock/src/nsock_read.c

/***************************************************************************
 * nsock_read.c -- This contains the functions for requesting various read *
 * events from the nsock parallel socket event library                     *
 *                                                                         *
 ***********************IMPORTANT NSOCK LICENSE TERMS***********************
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 ***************************************************************************/

/* $Id$ */

#include "nsock_internal.h"
#include "nsock_log.h"
#include "netutils.h"


/* Read up to nlines lines (terminated with \n, which of course includes \r\n),
 * or until EOF, or until the timeout, whichever comes first.  Note that
 * NSE_STATUS_SUCCESS will be returned in the case of EOF or timeout if at least
 * 1 char has been read.  Also note that you may get more than 'nlines' back --
 * we just stop once "at least" 'nlines' is read */
nsock_event_id nsock_readlines(nsock_pool nsp, nsock_iod ms_iod,
                               nsock_ev_handler handler, int timeout_msecs,
                               void *userdata, int nlines) {
  struct niod *nsi = (struct niod *)ms_iod;
  struct npool *ms = (struct npool *)nsp;
  struct nevent *nse;

  nse = event_new(ms, NSE_TYPE_READ, nsi, timeout_msecs, handler, userdata);
  assert(nse);

  nsock_log_info("Read request for %d lines from IOD #%li [%s] (timeout: %dms) EID %li",
                 nlines, nsi->id, get_peeraddr_string(nsi), timeout_msecs, nse->id);

  nse->readinfo.read_type = NSOCK_READLINES;
  nse->readinfo.num = nlines;

  nsock_pool_add_event(ms, nse);

  return nse->id;
}

/* Same as above, except it tries to read at least 'nbytes' instead of 'nlines'. */
nsock_event_id nsock_readbytes(nsock_pool nsp, nsock_iod ms_iod,
                               nsock_ev_handler handler, int timeout_msecs,
                               void *userdata, int nbytes) {

  struct niod *nsi = (struct niod *)ms_iod;
  struct npool *ms = (struct npool *)nsp;
  struct nevent *nse;

  nse = event_new(ms, NSE_TYPE_READ, nsi, timeout_msecs, handler, userdata);
  assert(nse);

  nsock_log_info("Read request for %d bytes from IOD #%li [%s] (timeout: %dms) EID %li",
                 nbytes, nsi->id, get_peeraddr_string(nsi), timeout_msecs, nse->id);

  nse->readinfo.read_type = NSOCK_READBYTES;
  nse->readinfo.num = nbytes;

  nsock_pool_add_event(ms, nse);

  return nse->id;
}


/* The simplest read function -- returns NSE_STATUS_SUCCESS when it
 * reads anything, otherwise it returns timeout, eof, or error as appropriate */
nsock_event_id nsock_read(nsock_pool nsp, nsock_iod ms_iod,
                          nsock_ev_handler handler, int timeout_msecs,
                          void *userdata) {
  struct niod *nsi = (struct niod *)ms_iod;
  struct npool *ms = (struct npool *)nsp;
  struct nevent *nse;

  nse = event_new(ms, NSE_TYPE_READ, nsi, timeout_msecs, handler, userdata);
  assert(nse);

  nsock_log_info("Read request from IOD #%li [%s] (timeout: %dms) EID %li",
                 nsi->id, get_peeraddr_string(nsi), timeout_msecs, nse->id);

  nse->readinfo.read_type = NSOCK_READ;

  nsock_pool_add_event(ms, nse);

  return nse->id;
}