sync_pipe_write.c

   1 /* sync_pipe_write.c
   2  *
   3  * $Id$
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation; either version 2
  12  * of the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  22  */
  23
  24 #include "config.h"
  25
  26 #include <string.h>
  27
  28 #ifdef HAVE_UNISTD_H
  29 #include <unistd.h>
  30 #endif
  31
  32 #ifdef _WIN32
  33 #include <io.h>
  34 #endif
  35
  36 #include <glib.h>
  37
  38 #include "sync_pipe.h"
  39 #include "log.h"
  40
  41 /****************************************************************************************************************/
  42 /* sync_pipe handling */
  43
  44
  45 /* write a single message header to the recipient pipe */
  46 ssize_t
  47 pipe_write_header(int pipe_fd, char indicator, int length)
  48 {
  49     guchar header[1+3]; /* indicator + 3-byte len */
  50
  51
  52     g_assert(length <= SP_MAX_MSG_LEN);
  53
  54     /* write header (indicator + 3-byte len) */
  55     header[0] = indicator;
  56     header[1] = (length >> 16) & 0xFF;
  57     header[2] = (length >> 8) & 0xFF;
  58     header[3] = (length >> 0) & 0xFF;
  59
  60     /* write header */
  61     return write(pipe_fd, header, sizeof header);
  62 }
  63
  64
  65 /* write a message to the recipient pipe in the standard format
  66    (3 digit message length (excluding length and indicator field),
  67    1 byte message indicator and the rest is the message).
  68    If msg is NULL, the message has only a length and indicator. */
  69 void
  70 pipe_write_block(int pipe_fd, char indicator, const char *msg)
  71 {
  72     ssize_t ret;
  73     int len;
  74
  75     /*g_warning("write %d enter", pipe_fd);*/
  76
  77     if(msg != NULL) {
  78         len = (int) strlen(msg) + 1;    /* including the terminating '\0'! */
  79     } else {
  80         len = 0;
  81     }
  82
  83     /* write header (indicator + 3-byte len) */
  84     ret = pipe_write_header(pipe_fd, indicator, len);
  85     if(ret == -1) {
  86         return;
  87     }
  88
  89     /* write value (if we have one) */
  90     if(len) {
  91         /*g_warning("write %d indicator: %c value len: %u msg: %s", pipe_fd, indicator, len, msg);*/
  92         ret = write(pipe_fd, msg, len);
  93         if(ret == -1) {
  94             return;
  95         }
  96     } else {
  97         /*g_warning("write %d indicator: %c no value", pipe_fd, indicator);*/
  98     }
  99
 100     /*g_warning("write %d leave", pipe_fd);*/
 101 }
 102
 103
 104 void
 105 sync_pipe_errmsg_to_parent(int pipe_fd, const char *error_msg,
 106                            const char *secondary_error_msg)
 107 {
 108
 109     /* first write a "master header" with the length of the two messages plus their "slave headers" */
 110     pipe_write_header(pipe_fd, SP_ERROR_MSG, (int) (strlen(error_msg) + 1 + 4 + strlen(secondary_error_msg) + 1 + 4));
 111     pipe_write_block(pipe_fd, SP_ERROR_MSG, error_msg);
 112     pipe_write_block(pipe_fd, SP_ERROR_MSG, secondary_error_msg);
 113 }