From: Robin Sonefors
Because the query handlers are plentiful and nifty, they're something I
should be using, but because I'm bad at remembering things and tired of
reading the source to find out how things work, I need help.
The way I can think of to get help is to try to exercise peer pressure
on whoever writes the query handler, by telling users that there should
be a help text, and then giving them errors error messages when the
query handler doesn't have any help text.
The protocol I've invented for asking for help text is the "--help"
command to the query handler - a fairly universal convention in
unixland, and also unlikely to clash with something else.
Signed-off-by: Robin Sonefors
---
base/query-handler.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/base/query-handler.c b/base/query-handler.c
index 8d3cfe3..f9c0604 100644
--- a/base/query-handler.c
+++ b/base/query-handler.c
@@ -257,6 +257,31 @@ void qh_deinit(const char *path)
unlink(path);
}
+static int qh_help(int sd, char *buf, unsigned int len)
+{
+ struct query_handler *qh;
+ if (!strcmp(buf, "list")) {
+ int i = 0;
+ for (qh = qhandlers; qh; qh = qh->next_qh) {
+ nsock_printf(sd, "%s\n", qh->name);
+ }
+ nsock_printf(sd, 0);
+ return 0;
+ }
+ if ((qh = qh_find_handler(buf)) != FALSE) {
+ int res = qh->handler(sd, "--help", 6);
+ if (res > 200) {
+ nsock_printf_nul(sd, "The handler %s doesn't have any help yet.", buf);
+ }
+ return 0;
+ }
+
+ nsock_printf_nul(sd, "This is the help query handler.\n"
+ "Try \"#help list\" to see all registered handlers, or\n"
+ "\"#help \" to get help on a specific handler.");
+ return 0;
+}
+
static int qh_core(int sd, char *buf, unsigned int len)
{
char *space;
@@ -342,5 +367,8 @@ int qh_init(const char *path)
if(!qh_register_handler("core", 0, qh_core))
logit(NSLOG_INFO_MESSAGE, FALSE, "qh: core query handler registered\n");
+ if(!qh_register_handler("help", 0, qh_help))
+ logit(NSLOG_INFO_MESSAGE, FALSE, "qh: help query handler registered\n");
+
return 0;
}
--
1.7.11.7
This post was automatically imported from historical nagios-devel mailing list archives
Original poster: robin.sonefors@op5.com