perl_require directive has effect only at first config

[KES777@…]

my configs are included as:

include /etc/nginx/sites-enabled/*.conf;

if I want to use 'perl_require' directive I should place it ONLY at first conf file (in alfabetical order)
If I put directive into any other conf file it even does not complain if I try to load unexisting module

[Maxim Dounin]

All perl_requires directives are processed when nginx creates a Perl interpreter. And this in turn happens when nginx parses first perl or perl_set directive (or after configuration parsing in there are no perl/perl_set directives in the configuration). That is, with a configuration like:

perl_require foo.pm;
server { ... location / { perl "..."; }}
perl_require bar.pm;
server { ... location / { perl "..."; }}

only foo.pm module will be loaded.

The following patch fixes this by loading required modules before each perl/perl_set directive:

# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1480622026 -10800
#      Thu Dec 01 22:53:46 2016 +0300
# Node ID 123f22ed6e7a4ff291c62fb17c9ccb5343b3aa02
# Parent  079b7b81c47261ae0de2a48f2bc2d64aa2779ef4
Perl: loading of additional required modules (ticket #994).

Previously, in a configuration like

    perl_require foo.pm;
    server { ... location / { perl "..."; }}
    perl_require bar.pm;
    server { ... location / { perl "..."; }}

the "bar.pm" module was completely ignored, as all required modules were
only loaded when creating an interpreter during parsing the perl directive
in the first server{} block.

Fix is to load additional modules, if any, by calling
the ngx_http_perl_run_requires() function again on each perl/perl_set
parsing.  This is relatively cheap even without tracking of what we've
already loaded as Perl does it itself and simply ignores attempts to load
already loaded modules.

diff --git a/src/http/modules/perl/ngx_http_perl_module.c b/src/http/modules/perl/ngx_http_perl_module.c
--- a/src/http/modules/perl/ngx_http_perl_module.c
+++ b/src/http/modules/perl/ngx_http_perl_module.c
@@ -943,6 +943,10 @@ ngx_http_perl(ngx_conf_t *cf, ngx_comman
     PERL_SET_CONTEXT(pmcf->perl);
     PERL_SET_INTERP(pmcf->perl);
 
+    if (ngx_http_perl_run_requires(aTHX_ pmcf->requires, cf->log) != NGX_OK) {
+        return NGX_CONF_ERROR;
+    }
+
     ngx_http_perl_eval_anon_sub(aTHX_ &value[1], &plcf->sub);
 
     if (plcf->sub == &PL_sv_undef) {
@@ -1015,6 +1019,10 @@ ngx_http_perl_set(ngx_conf_t *cf, ngx_co
     PERL_SET_CONTEXT(pmcf->perl);
     PERL_SET_INTERP(pmcf->perl);
 
+    if (ngx_http_perl_run_requires(aTHX_ pmcf->requires, cf->log) != NGX_OK) {
+        return NGX_CONF_ERROR;
+    }
+
     ngx_http_perl_eval_anon_sub(aTHX_ &value[2], &pv->sub);
 
     if (pv->sub == &PL_sv_undef) {