/******************************************************************************
* *
* Function: read_traps *
* *
* Purpose: read the traps and then parse them with parse_traps() *
* *
* Author: Rudolfs Kreicbergs *
* *
******************************************************************************/
static int read_traps()
{
const char *__function_name = "read_traps";
int nbytes = 0;
zabbix_log(LOG_LEVEL_DEBUG, "In %s() lastsize:%d", __function_name, trap_lastsize);
if ((off_t)-1 == lseek(trap_fd, (off_t)trap_lastsize, SEEK_SET))
{
zabbix_log(LOG_LEVEL_WARNING, "cannot set position to %d for \"%s\": %s", trap_lastsize,
CONFIG_SNMPTRAP_FILE, zbx_strerror(errno));
goto exit;
}
if (-1 == (nbytes = read(trap_fd, buffer + offset, MAX_BUFFER_LEN - offset - 1)))
{
zabbix_log(LOG_LEVEL_WARNING, "cannot read from SNMP trapper file \"%s\": %s", CONFIG_SNMPTRAP_FILE,
zbx_strerror(errno));
goto exit;
}
if (0 < nbytes)
{
if (ZBX_SNMP_TRAPFILE_MAX_SIZE <= (zbx_uint64_t)trap_lastsize + nbytes)
{
nbytes = 0;
goto exit;
}
buffer[nbytes + offset] = '\0';
trap_lastsize += nbytes;
DBupdate_lastsize();
parse_traps(0);
}
exit:
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __function_name);
return nbytes;
}
/******************************************************************************
* *
* Function: read_traps *
* *
* Purpose: read the traps and then parse them with parse_traps() *
* *
* Author: Rudolfs Kreicbergs *
* *
******************************************************************************/
static void read_traps()
{
const char *__function_name = "read_traps";
int nbytes;
char buffer[MAX_BUFFER_LEN];
zabbix_log(LOG_LEVEL_DEBUG, "In %s() lastsize:%d", __function_name, trap_lastsize);
*buffer = '\0';
if ((off_t)-1 == lseek(trap_fd, (off_t)trap_lastsize, SEEK_SET))
{
zabbix_log(LOG_LEVEL_WARNING, "cannot set position to [%d] for [%s]: %s",
trap_lastsize, CONFIG_SNMPTRAP_FILE, zbx_strerror(errno));
goto exit;
}
if (-1 == (nbytes = read(trap_fd, buffer, sizeof(buffer) - 1)))
{
zabbix_log(LOG_LEVEL_WARNING, "cannot read from [%s]: %s",
CONFIG_SNMPTRAP_FILE, zbx_strerror(errno));
goto exit;
}
if (0 < nbytes)
{
buffer[nbytes] = '\0';
zbx_rtrim(buffer + MAX(nbytes - 3, 0), " \r\n");
trap_lastsize += nbytes;
DBupdate_lastsize();
parse_traps(buffer);
}
exit:
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __function_name);
}
/******************************************************************************
* *
* Function: get_latest_data *
* *
* Purpose: Open the latest trap file. If the current file has been rotated, *
* process that and then open the latest file. *
* *
* Return value: SUCCEED - there are new traps to be parsed *
* FAIL - there are no new traps or trap file does not exist *
* *
* Author: Rudolfs Kreicbergs *
* *
******************************************************************************/
static int get_latest_data()
{
zbx_stat_t file_buf;
if (-1 != trap_fd) /* a trap file is already open */
{
if (0 != zbx_stat(CONFIG_SNMPTRAP_FILE, &file_buf))
{
/* file might have been renamed or deleted, process the current file */
if (ENOENT != errno)
{
zabbix_log(LOG_LEVEL_CRIT, "cannot stat SNMP trapper file \"%s\": %s",
CONFIG_SNMPTRAP_FILE, zbx_strerror(errno));
}
while (0 < read_traps())
;
if (0 != offset)
parse_traps(1);
close_trap_file();
}
else if (ZBX_SNMP_TRAPFILE_MAX_SIZE <= (zbx_uint64_t)file_buf.st_size)
{
close_trap_file();
}
else if (file_buf.st_ino != trap_ino || file_buf.st_size < trap_lastsize)
{
/* file has been rotated, process the current file */
while (0 < read_traps())
;
if (0 != offset)
parse_traps(1);
close_trap_file();
}
else if (file_buf.st_size == trap_lastsize)
{
if (1 == force)
{
parse_traps(1);
force = 0;
}
else if (0 != offset && 0 == force)
{
force = 1;
}
return FAIL; /* no new traps */
}
}
force = 0;
if (-1 == trap_fd && -1 == open_trap_file())
return FAIL;
return SUCCEED;
}
/******************************************************************************
* *
* Function: parse_traps *
* *
* Purpose: split traps and process them with process_trap() *
* *
* Author: Rudolfs Kreicbergs *
* *
******************************************************************************/
static void parse_traps(int flag)
{
char *c, *line, *begin = NULL, *end = NULL, *addr = NULL, *pzbegin, *pzaddr = NULL, *pzdate = NULL;
c = line = buffer;
while ('\0' != *c)
{
if ('\n' == *c)
{
line = ++c;
continue;
}
if (0 != strncmp(c, "ZBXTRAP", 7))
{
c++;
continue;
}
pzbegin = c;
c += 7; /* c now points to the delimiter between "ZBXTRAP" and address */
while ('\0' != *c && NULL != strchr(ZBX_WHITESPACE, *c))
c++;
/* c now points to the address */
/* process the previous trap */
if (NULL != begin)
{
*(line - 1) = '\0';
*pzdate = '\0';
*pzaddr = '\0';
process_trap(addr, begin, end);
end = NULL;
}
/* parse the current trap */
begin = line;
addr = c;
pzdate = pzbegin;
while ('\0' != *c && NULL == strchr(ZBX_WHITESPACE, *c))
c++;
pzaddr = c;
end = c + 1; /* the rest of the trap */
}
if (0 == flag)
{
if (NULL == begin)
offset = c - buffer;
else
offset = c - begin;
if (offset == MAX_BUFFER_LEN - 1)
{
if (NULL != end)
{
zabbix_log(LOG_LEVEL_WARNING, "SNMP trapper buffer is full,"
" trap data might be truncated");
parse_traps(1);
}
else
zabbix_log(LOG_LEVEL_WARNING, "failed to find trap in SNMP trapper file");
offset = 0;
*buffer = '\0';
}
else
{
if (NULL != begin && begin != buffer)
memmove(buffer, begin, offset + 1);
}
}
else
{
if (NULL != end)
{
*(line - 1) = '\0';
*pzdate = '\0';
*pzaddr = '\0';
process_trap(addr, begin, end);
offset = 0;
*buffer = '\0';
}
else
{
zabbix_log(LOG_LEVEL_WARNING, "invalid trap data found \"%s\"", buffer);
offset = 0;
*buffer = '\0';
}
}
}
