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Re: uninitialised value & valgrind

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"James Kuyper" <jameskuyper@verizon.net> wrote in message 
news:4FE9F706.6060301@verizon.net...
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> The messages you're getting from valgrind suggest that something is
> attempting to access the non-existent message data inside of __write().
> You don't show us how msg_len is calculated. However, if it's greater
> than sizeof(struct vlog_msg_header), that would explain the messages
> from valgrind.
>
> I'd recommend figuring out why msg_len Is greater than that limit - it
> suggests a serious disconnect between what you think you're doing and
> what you're actually doing. The most plausible kind of mistake would be
> failing to set header.vmh_data_len to 0.

#define VLOG_MSG_HDR_SIZE sizeof (struct vlog_msg_header)
int vlog_client_send_message (struct vlog_msg *msg)
{
   u_int16_t msg_len = VLOG_MSG_HDR_SIZE + msg->vms_msg_hdr.vmh_data_len;
   ...
}

and this is how 'header' is initialised:

  struct vlog_msg_header header;
  ...
  header.vmh_msg_type = VLOG_MSG_TYPE_CTRL;
  header.vmh_vr_id    = 0;
  header.vmh_mod_id   = zg->protocol;
  header.vmh_proc_id  = pal_get_process_id();
  header.vmh_priority = 0;
  header.vmh_data_len = 0;
  vlog_client_send_message (zg->vlog_clt, (struct vlog_msg *)&header);
  ...

So msg_len should be of valid length.

Mark 

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uninitialised value & valgrind "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2012-06-26 12:35 -0400
  Re: uninitialised value & valgrind James Kuyper <jameskuyper@verizon.net> - 2012-06-26 13:53 -0400
    Re: uninitialised value & valgrind "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2012-06-26 14:07 -0400
      Re: uninitialised value & valgrind James Kuyper <jameskuyper@verizon.net> - 2012-06-26 15:42 -0400
  Re: uninitialised value & valgrind Johann Klammer <klammerj@NOSPAM.a1.net> - 2012-06-27 02:09 +0200

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