MINOR: fcgi-app: Use the filter configuration helpers for lookups and checks

Look up the FCGI filter configuration of a proxy with flt_find_conf()
instead of scanning the legacy filter_configs and then falling back to the
finalized instances. The helper already selects the right source
according to the proxy mode.

Rework fcgi_flt_check() to walk the filter configurations with
flt_foreach_conf() and check the uniqueness of the FCGI application and
the implicit declaration rules in a dedicated callback.

The callback now considers any second FCGI filter of the proxy as an
error, including one referring to the same application, since a single
FCGI filter remains supported per proxy.

diff --git a/src/fcgi-app.c b/src/fcgi-app.c
index 050857a7d03bcbe62a4aac35f1fe6832b396ace5..0034e302705b8350bae36dccbdfdb80bbb128b30 100644 (file)
--- a/src/fcgi-app.c
+++ b/src/fcgi-app.c
@@ -84,22 +84,10 @@ struct fcgi_app *fcgi_app_find_by_name(const char *name)
 
 struct fcgi_flt_conf *find_px_fcgi_conf(struct proxy *px)
 {
-       struct filter_instance *inst;
        struct flt_conf *fconf;
 
-       list_for_each_entry(fconf, &px->filter_configs, list) {
-               if (fconf->id == fcgi_flt_id)
-                       return fconf->conf;
-       }
-
-       /* no legacy filter found, look for a finalized fcgi filter instance
-        * (instances are not finalized during the configuration parsing, in
-        * that case they are skipped)
-        */
-       inst = flt_find_instance(px, filter_find_class(fcgi_filter_cls_name), NULL);
-       if (inst && inst->fconf)
-               return inst->fconf->conf;
-       return NULL;
+       fconf = flt_find_conf(px, fcgi_flt_id, FLT_SIDE_REQ, NULL, NULL);
+       return fconf ? fconf->conf : NULL;
 }
 
 struct fcgi_flt_ctx *find_strm_fcgi_ctx(struct stream *s)
@@ -220,13 +208,60 @@ static void fcgi_flt_deinit(struct proxy *px, struct flt_conf *fconf)
        free(fcgi_conf);
 }
 
+/* Context for fcgi_flt_check_one() */
+struct fcgi_flt_check_ctx {
+       struct proxy *px;
+       struct flt_conf *fconf;
+       struct fcgi_flt_conf *fcgi_conf;
+};
+
+/* Checks the fcgi filter <f> against the fcgi filter being checked. There must
+ * be only one fcgi-app per backend, and in legacy mode, an implicit fcgi
+ * declaration is only allowed with the compression and cache filters.
+ * Returns -1 on error, 0 otherwise.
+ */
+static int fcgi_flt_check_one(struct flt_conf *f, void *data)
+{
+       struct fcgi_flt_check_ctx *ctx = data;
+
+       /* This is the current FCGI filter */
+       if (f == ctx->fconf)
+               return 0;
+
+       /* Having several fcgi filters on the same proxy is not supported*/
+       if (f->id == ctx->fconf->id) {
+               ha_alert("proxy '%s' : only one fcgi-app supported per backend.\n",
+                        ctx->px->id);
+               return -1;
+       }
+
+       /* Legacy filters not used for this proxy, we can continue */
+       if (!flt_use_legacy_filter(ctx->px))
+               return 0;
+
+       /* In legacy mode, implicit declaration is only allowed with the
+        * compression, decompression and cache. For other filters, an explicit
+        * declaration is required. */
+       if (f->id == http_comp_req_flt_id  || f->id == http_comp_res_flt_id ||
+           f->id == decomp_req_flt_id  || f->id == decomp_res_flt_id ||
+           f->id == cache_store_flt_id)
+               return 0;
+       if (ctx->fcgi_conf->flags & FCGI_FLT_F_IMPLICIT_DECL) {
+               ha_alert("proxy '%s': require an explicit filter declaration "
+                        "to use the fcgi-app '%s'.\n", ctx->px->id, ctx->fcgi_conf->name);
+               return -1;
+       }
+
+       return 0;
+}
+
 static int fcgi_flt_check(struct proxy *px, struct flt_conf *fconf)
 {
        struct fcgi_flt_conf  *fcgi_conf = fconf->conf;
        struct fcgi_rule_conf *crule, *back;
        struct fcgi_rule *rule = NULL;
-       struct flt_conf *f;
        char *errmsg = NULL;
+       struct fcgi_flt_check_ctx ctx = { .px = px, .fconf = fconf, .fcgi_conf = fcgi_conf };
 
        fcgi_conf->app = fcgi_app_find_by_name(fcgi_conf->name);
        if (!fcgi_conf->app) {
@@ -235,26 +270,8 @@ static int fcgi_flt_check(struct proxy *px, struct flt_conf *fconf)
                goto err;
        }
 
-       list_for_each_entry(f, &px->filter_configs, list) {
-               if (f->id == http_comp_req_flt_id || f->id == http_comp_res_flt_id ||
-                   f->id == cache_store_flt_id)
-                       continue;
-               else if ((f->id == fconf->id) && f->conf != fcgi_conf &&
-                        strcmp(((struct fcgi_flt_conf *)f->conf)->name, fcgi_conf->name) != 0) {
-                       /* another fcgi filter with a different app */
-                       ha_alert("proxy '%s' : only one fcgi-app supported per backend.\n",
-                                px->id);
-                       goto err;
-               }
-               else if ((f->id != fconf->id) && (fcgi_conf->flags & FCGI_FLT_F_IMPLICIT_DECL)) {
-                       /* Implicit declaration is only allowed with the
-                        * compression and cache. For other filters, an explicit
-                        * declaration is required. */
-                       ha_alert("config: proxy '%s': require an explicit filter declaration "
-                                "to use the fcgi-app '%s'.\n", px->id, fcgi_conf->name);
-                       goto err;
-               }
-       }
+       if (flt_foreach_conf(px, FLT_SIDE_REQ, fcgi_flt_check_one, &ctx) < 0)
+               goto err;
 
        list_for_each_entry_safe(crule, back, &fcgi_conf->app->conf.rules, list) {
                rule = calloc(1, sizeof(*rule));