source3/lib/util_tsock.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Utilities around tsocket
   4    Copyright (C) Volker Lendecke 2009
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21
  22 struct tstream_read_packet_state {
  23         struct tevent_context *ev;
  24         struct tstream_context *stream;
  25         ssize_t (*more)(uint8_t *buf, size_t buflen, void *private_data);
  26         void *private_data;
  27         uint8_t *buf;
  28         struct iovec iov;
  29 };
  30
  31 static void tstream_read_packet_done(struct tevent_req *subreq);
  32
  33 struct tevent_req *tstream_read_packet_send(TALLOC_CTX *mem_ctx,
  34                                             struct tevent_context *ev,
  35                                             struct tstream_context *stream,
  36                                             size_t initial,
  37                                             ssize_t (*more)(uint8_t *buf,
  38                                                             size_t buflen,
  39                                                             void *private_data),
  40                                             void *private_data)
  41 {
  42         struct tevent_req *req, *subreq;
  43         struct tstream_read_packet_state *state;
  44
  45         req = tevent_req_create(mem_ctx, &state,
  46                                 struct tstream_read_packet_state);
  47         if (req == NULL) {
  48                 return NULL;
  49         }
  50         state->buf = talloc_array(state, uint8_t, initial);
  51         if (tevent_req_nomem(state->buf, req)) {
  52                 return tevent_req_post(req, ev);
  53         }
  54         state->iov.iov_base = (void *)state->buf;
  55         state->iov.iov_len = initial;
  56
  57         state->ev = ev;
  58         state->stream = stream;
  59         state->more = more;
  60         state->private_data = private_data;
  61
  62         subreq = tstream_readv_send(state, ev, stream, &state->iov, 1);
  63         if (tevent_req_nomem(subreq, req)) {
  64                 return tevent_req_post(req, ev);
  65         }
  66         tevent_req_set_callback(subreq, tstream_read_packet_done, req);
  67
  68         return req;
  69 }
  70
  71 static void tstream_read_packet_done(struct tevent_req *subreq)
  72 {
  73         struct tevent_req *req = tevent_req_callback_data(
  74                 subreq, struct tevent_req);
  75         struct tstream_read_packet_state *state = tevent_req_data(
  76                 req, struct tstream_read_packet_state);
  77         int ret, err;
  78         size_t total;
  79         ssize_t more;
  80         uint8_t *tmp;
  81
  82         ret = tstream_readv_recv(subreq, &err);
  83         TALLOC_FREE(subreq);
  84         if (ret == 0) {
  85                 err = EPIPE;
  86         }
  87         if (ret <= 0) {
  88                 tevent_req_error(req, err);
  89                 return;
  90         }
  91
  92         if (state->more == NULL) {
  93                 /* Nobody to ask, this is a async read_data */
  94                 tevent_req_done(req);
  95                 return;
  96         }
  97         total = talloc_array_length(state->buf);
  98
  99         more = state->more(state->buf, total, state->private_data);
 100         if (more == -1) {
 101                 /* We got an invalid packet, tell the caller */
 102                 tevent_req_error(req, EIO);
 103                 return;
 104         }
 105         if (more == 0) {
 106                 /* We're done, full packet received */
 107                 tevent_req_done(req);
 108                 return;
 109         }
 110
 111         tmp = talloc_realloc(state, state->buf, uint8_t, total+more);
 112         if (tevent_req_nomem(tmp, req)) {
 113                 return;
 114         }
 115         state->buf = tmp;
 116
 117         state->iov.iov_base = (void *)(state->buf + total);
 118         state->iov.iov_len = more;
 119
 120         subreq = tstream_readv_send(state, state->ev, state->stream,
 121                                     &state->iov, 1);
 122         if (tevent_req_nomem(subreq, req)) {
 123                 return;
 124         }
 125         tevent_req_set_callback(subreq, tstream_read_packet_done, req);
 126 }
 127
 128 ssize_t tstream_read_packet_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 129                                  uint8_t **pbuf, int *perrno)
 130 {
 131         struct tstream_read_packet_state *state =
 132                 tevent_req_data(req, struct tstream_read_packet_state);
 133
 134         if (tevent_req_is_unix_error(req, perrno)) {
 135                 return -1;
 136         }
 137         *pbuf = talloc_move(mem_ctx, &state->buf);
 138         return talloc_array_length(*pbuf);
 139 }