[PATCH v3 5/6] MINOR: check: Support generating a `unique_id` for checks

[Tim Duesterhus]

This implementation is directly modeled after `stream_generate_unique_id()` and
the corresponding `unique_id` field on `struct stream`.

It will be used in a future commit to enable the use of the `%[unique-id]`
fetch in check rules.
---
 include/haproxy/check-t.h |  1 +
 include/haproxy/check.h   | 11 +++++++++++
 src/check.c               |  7 +++++++
 3 files changed, 19 insertions(+)

diff --git a/include/haproxy/check-t.h b/include/haproxy/check-t.h
index f9f378e8a..353fc5845 100644
--- a/include/haproxy/check-t.h
+++ b/include/haproxy/check-t.h
@@ -199,6 +199,7 @@ struct check {
        const struct mux_proto_list *mux_proto; /* the mux to use for all 
outgoing connections (specified by the "proto" keyword) */
        struct list check_queue;                /* entry in the check queue. 
Not empty = in queue. */
        int via_socks4;                         /* check the connection via 
socks4 proxy */
+       struct ist unique_id;                   /* custom unique ID, same as in 
struct stream */
 };
 
 #endif /* _HAPROXY_CHECKS_T_H */
diff --git a/include/haproxy/check.h b/include/haproxy/check.h
index 09e195a46..e25e987f0 100644
--- a/include/haproxy/check.h
+++ b/include/haproxy/check.h
@@ -26,6 +26,7 @@
 #include <haproxy/proxy-t.h>
 #include <haproxy/server-t.h>
 #include <haproxy/trace-t.h>
+#include <haproxy/log.h>
 
 extern struct trace_source trace_check;
 
@@ -80,6 +81,16 @@ struct task *srv_chk_io_cb(struct task *t, void *ctx, 
unsigned int state);
 int check_buf_available(void *target);
 struct buffer *check_get_buf(struct check *check, struct buffer *bptr, 
unsigned int small_buffer);
 void check_release_buf(struct check *check, struct buffer *bptr);
+
+static inline struct ist check_generate_unique_id(struct check *check, struct 
lf_expr *format)
+{
+       if (!isttest(check->unique_id)) {
+               generate_unique_id(&check->unique_id, check->sess, NULL, 
format);
+       }
+
+       return check->unique_id;
+}
+
 const char *init_check(struct check *check, int type);
 void free_check(struct check *check);
 void check_purge(struct check *check);
diff --git a/src/check.c b/src/check.c
index 45baca979..481cab22f 100644
--- a/src/check.c
+++ b/src/check.c
@@ -458,6 +458,11 @@ void set_server_check_status(struct check *check, short 
status, const char *desc
                check->result = CHK_RES_UNKNOWN;        /* no result yet */
                check->desc[0] = '\0';
                check->start = now_ns;
+
+               /* Reset unique_id. */
+               pool_free(pool_head_uniqueid, istptr(check->unique_id));
+               check->unique_id = IST_NULL;
+
                return;
        }
 
@@ -1558,6 +1563,8 @@ void free_check(struct check *check)
                ha_free(&check->tcpcheck);
        }
 
+       pool_free(pool_head_uniqueid, istptr(check->unique_id));
+       check->unique_id = IST_NULL;
        ha_free(&check->pool_conn_name);
        ha_free(&check->sni);
        ha_free(&check->alpn_str);
-- 
2.53.0