Implement IP lookup and match mode.

* src/ping903.c: Implement two new endpoints: /ip and /match, for
IP lookup and match mode.
* src/ping903.h (get_ipaddr_stat)
(get_host_matches): New protos.
* src/pinger.c (get_ipaddr_stat)
(get_host_matches): New functions.
* src/ping903q.c (resolve_ip): New global.
(query_host): Use /host or /ip depending on the value of resolve_ip.
(match_host): New function.
* doc/ping903q.1: Update.

1 files changed, 25 insertions, 5 deletions

diff --git a/doc/ping903q.1 b/doc/ping903q.1
index 2d351a3..326ca81 100644
--- a/doc/ping903q.1
+++ b/doc/ping903q.1
@@ -21,14 +21,16 @@ ping903q \- ping903 query tool
  [\fB\-hVv\fR]\
  [\fB\-f \fIFILE\fR]\
  [\fIIP\fR]
-
-or
-
+.PP
 \fBping903q\fR\
   [\fB\-f \fIFILE\fR]\
   \fB\-H \fIHOST\fR\
   \fB\-c \fIRTA\fB,\fIPCT\fB%\fR\
-  \fB\-w \fIRTA\fB,\fIPCT\fB%\fR  
+  \fB\-w \fIRTA\fB,\fIPCT\fB%\fR
+.PP
+\fBping903q\fR\
+  [\fB\-f \fIFILE\fR]\
+  \fB\-m\fR
 .SH DESCRIPTION
 Queries monitoring statistics from the \fBping903\fR daemon.  When
 used with a single argument (\fIIP\fR), displays information about
@@ -54,6 +56,10 @@ When the \fB\-H\fR, \fB\-c\fR, and \fB\-w\fR options are used, the
 program enters \fINagios check mode\fR.  In this mode its output
 complies with the requirements for external \fBNagios\fR check
 programs.
+.SS Match mode
+When invoked with the \fB\-m\fR option, \fBping903q\fR checks if
+\fIHOST\fR is monitored by the server.  If so, it prints the matching
+host names and exits with code 0.
 .SH EXIT CODE
 When called with one argument, the program exits with code 0 (success)
 if the IP is alive and 2 otherwise.
@@ -73,6 +79,9 @@ Warning condition.
 .B 2
 Critical condition.
 .PP
+In match mode, the program exits with code 0 if the requested host is
+monitored by the server, and with code 2 if it is not.
+.PP
 If any error is encountered, \fBping903q\fR exits with status \fB3\fR.
 .SH OPTIONS
 .TP
@@ -83,12 +92,19 @@ Read configuration from \fIFILE\fR instead of from the default
 .B \-h
 Print a short usage summary.
 .TP
+.B \-r
+Resolve host argument to IP address and use the IP address to query
+the server.  Using this option you can supply a symbolic host name
+as argument even if the server uses the corresponding IP and still get
+a meaningful result.  Otherwise, you can use the matching mode (see
+below).
+.TP
 .B \-V
 Print program version, copyright information, and exit.
 .TP
 .B \-v
 Turn on verbose output.
-.SS Options valid in Nagios check mode
+.SS Options specific for Nagios check mode
 The presense of any of these options switches \fBping903q\fR to Nagios
 check mode.  For this mode to succeed, all three options must be specified.
 .TP
@@ -107,6 +123,10 @@ also that the use of the percent sign is mandatory.
 \fB\-w \fIRTA\fB,\fIPCT\fB%\fR
 Sets the warning threshold value.  See above for the discussion of the
 arguments.
+.SS Options specific for match mode
+.TP
+.B \-m
+Switch to the host match mode.
 .SH SEE ALSO
 .BR ping903 (8),
 .BR Nagios <https://www.nagios.org/>.