Add support for Perl 5.22.x.

As outlined by Leon Timmermans in [perl #123687]:

  lookup %ENV's magic, and then replace the pointer to PL_vtbl_env with
  a pointer to MP_vtbl_env. You may have to add some svt_copy magic to
  make it cast MP_vtbl_envelem instead of PL_vtbl_envelem on the elements.

with an added svt_local for the 'local %ENV' tests.

While at it, augment t/modperl/env.t to check that deleting %ENV elements really removes them from subprocess_env. This highlights the need for modifying their vtable, currently in the modperl_envelem_tie() macro.

(MP_vtbl_envelem probably shouldn't be a global variable, but the modperl_envelem_tie() macro needs it, and the perl vtables are global too anyway. I've made MP_vtbl_env global too for symmetry.)

Based on ++Niko Tyni's 0001-Steps-at-Perl-5.22-compatibility-take-3.patch in [rt.cpan.org #101962].

Bug: https://rt.cpan.org/Public/Bug/Display.html?id=101962
Bug: https://rt.perl.org/Ticket/Display.html?id=123687


git-svn-id: https://svn.apache.org/repos/asf/perl/modperl/trunk@1717474 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/Changes b/Changes
index 8f15756..fdade41 100644
--- a/Changes
+++ b/Changes
@@ -12,6 +12,8 @@
 
 =item 2.0.10-dev
 
+Add support for Perl 5.22.x. [Niko Tyni <ntyni@iki.fi>, Steve Hay]
+
 =item 2.0.9 June 18, 2015
 
 Add note to README about MP_INLINE problem when building with GCC 5.
diff --git a/src/modules/perl/mod_perl.c b/src/modules/perl/mod_perl.c
index 1148bc0..1e17747 100644
--- a/src/modules/perl/mod_perl.c
+++ b/src/modules/perl/mod_perl.c
@@ -262,6 +262,8 @@
         exit(1);
     }
 
+    modperl_env_init(aTHX);
+
     /* suspend END blocks to be run at server shutdown */
     endav = PL_endav;
     PL_endav = (AV *)NULL;
@@ -576,9 +578,6 @@
     /* modifies PL_ppaddr */
     modperl_perl_pp_set_all();
 
-    /* modifies PL_vtbl_env{elem} */
-    modperl_env_init();
-
     return APR_SUCCESS;
 }
 
@@ -597,8 +596,6 @@
 
     MP_TRACE_i(MP_FUNC, "mod_perl sys term");
 
-    modperl_env_unload();
-
     modperl_perl_pp_unset_all();
 
     PERL_SYS_TERM();
diff --git a/src/modules/perl/modperl_env.c b/src/modules/perl/modperl_env.c
index c1a276b..874652f 100644
--- a/src/modules/perl/modperl_env.c
+++ b/src/modules/perl/modperl_env.c
@@ -121,6 +121,7 @@
     const apr_array_header_t *array;
     apr_table_entry_t *elts;
 
+    modperl_env_init(aTHX);
     modperl_env_untie(mg_flags);
 
     array = apr_table_elts(table);
@@ -431,14 +432,10 @@
 #endif
 }
 
-/* to store the original virtual tables
- * these are global, not per-interpreter
+/* handy access to perl's original virtual tables
  */
-static MGVTBL MP_PERL_vtbl_env;
-static MGVTBL MP_PERL_vtbl_envelem;
-
 #define MP_PL_vtbl_call(name, meth) \
-    MP_PERL_vtbl_##name.svt_##meth(aTHX_ sv, mg)
+    PL_vtbl_##name.svt_##meth(aTHX_ sv, mg)
 
 #define MP_dENV_KEY \
     STRLEN klen; \
@@ -529,6 +526,26 @@
     return 0;
 }
 
+static int modperl_env_magic_copy(pTHX_ SV *sv, MAGIC *mg, SV *nsv, const char *name, I32 namlen)
+{
+    MP_TRACE_e(MP_FUNC, "setting up %%ENV element magic");
+    sv_magicext(nsv, mg->mg_obj, toLOWER(mg->mg_type), &MP_vtbl_envelem, name, namlen);
+
+    return 1;
+}
+
+static int modperl_env_magic_local_all(pTHX_ SV *nsv, MAGIC *mg)
+{
+    MAGIC *nmg;
+    MP_TRACE_e(MP_FUNC, "localizing %%ENV");
+    nmg = sv_magicext(nsv, mg->mg_obj, mg->mg_type, &MP_vtbl_env, (char*)NULL, 0);
+    nmg->mg_ptr = mg->mg_ptr;
+    nmg->mg_flags |= MGf_COPY;
+    nmg->mg_flags |= MGf_LOCAL;
+
+    return 1;
+}
+
 static int modperl_env_magic_set(pTHX_ SV *sv, MAGIC *mg)
 {
     request_rec *r = (request_rec *)EnvMgObj;
@@ -613,15 +630,18 @@
 #endif
 
 /* override %ENV virtual tables with our own */
-static MGVTBL MP_vtbl_env = {
+MGVTBL MP_vtbl_env = {
     0,
     modperl_env_magic_set_all,
     0,
     modperl_env_magic_clear_all,
-    0
+    0,
+    modperl_env_magic_copy,
+    0,
+    modperl_env_magic_local_all
 };
 
-static MGVTBL MP_vtbl_envelem = {
+MGVTBL MP_vtbl_envelem = {
     0,
     modperl_env_magic_set,
     0,
@@ -629,22 +649,64 @@
     0
 };
 
-void modperl_env_init(void)
+void modperl_env_init(pTHX)
 {
-    /* save originals */
-    StructCopy(&PL_vtbl_env, &MP_PERL_vtbl_env, MGVTBL);
-    StructCopy(&PL_vtbl_envelem, &MP_PERL_vtbl_envelem, MGVTBL);
+    MAGIC *mg;
 
-    /* replace with our versions */
-    StructCopy(&MP_vtbl_env, &PL_vtbl_env, MGVTBL);
-    StructCopy(&MP_vtbl_envelem, &PL_vtbl_envelem, MGVTBL);
+    /* Find the 'E' magic on %ENV */
+    if (!my_perl)
+        return;
+    if (!PL_envgv)
+        return;
+    if (!SvRMAGICAL(ENVHV))
+        return;
+    mg = mg_find((const SV *)ENVHV, PERL_MAGIC_env);
+    if (!mg)
+        return;
+       
+    /* Ignore it if it isn't perl's original version */
+    if (mg->mg_virtual != &PL_vtbl_env)
+        return;
+
+    MP_TRACE_e(MP_FUNC, "env_init - ptr: %x obj: %x flags: %x",
+               mg->mg_ptr, mg->mg_obj, mg->mg_flags);
+
+    /* Remove it */
+    mg_free_type((SV*)ENVHV, PERL_MAGIC_env);
+
+    /* Add our version instead */
+    mg = sv_magicext((SV*)ENVHV, (SV*)NULL, PERL_MAGIC_env, &MP_vtbl_env, (char*)NULL, 0);
+    mg->mg_flags |= MGf_COPY;
+    mg->mg_flags |= MGf_LOCAL;
 }
 
-void modperl_env_unload(void)
+void modperl_env_unload(pTHX)
 {
-    /* restore originals */
-    StructCopy(&MP_PERL_vtbl_env, &PL_vtbl_env, MGVTBL);
-    StructCopy(&MP_PERL_vtbl_envelem, &PL_vtbl_envelem, MGVTBL);
+    MAGIC *mg;
+
+    /* Find the 'E' magic on %ENV */
+    if (!my_perl)
+        return;
+    if (!PL_envgv)
+        return;
+    if (!SvRMAGICAL(ENVHV))
+        return;
+    mg = mg_find((const SV *)ENVHV, PERL_MAGIC_env);
+    if (!mg)
+        return;
+
+    /* Ignore it if it isn't our version */
+    if (mg->mg_virtual != &MP_vtbl_env)
+        return;
+
+    MP_TRACE_e(MP_FUNC, "env_unload - ptr: %x obj: %x flags: %x",
+               mg->mg_ptr, mg->mg_obj, mg->mg_flags);
+
+    /* Remove it */
+    mg_free_type((SV*)ENVHV, PERL_MAGIC_env);
+
+    /* Restore perl's original version */
+    sv_magicext((SV*)ENVHV, (SV*)NULL, PERL_MAGIC_env, &PL_vtbl_env, (char*)NULL, 0);
 }
 
 /*
diff --git a/src/modules/perl/modperl_env.h b/src/modules/perl/modperl_env.h
index 406e345..cb2f060 100644
--- a/src/modules/perl/modperl_env.h
+++ b/src/modules/perl/modperl_env.h
@@ -28,7 +28,7 @@
     MP_magical_tie(ENVHV, mg_flags)
 
 #define modperl_envelem_tie(sv, key, klen) \
-    sv_magic(sv, (SV *)NULL, 'e', key, klen)
+    sv_magicext(sv, (SV *)NULL, PERL_MAGIC_envelem, &MP_vtbl_envelem, key, klen)
 
 void modperl_env_hash_keys(pTHX);
 
@@ -58,9 +58,12 @@
 
 void modperl_env_request_untie(pTHX_ request_rec *r);
 
-void modperl_env_init(void);
+void modperl_env_init(pTHX);
 
-void modperl_env_unload(void);
+void modperl_env_unload(pTHX);
+
+MGVTBL MP_vtbl_env;
+MGVTBL MP_vtbl_envelem;
 
 #endif /* MODPERL_ENV_H */
 
diff --git a/src/modules/perl/modperl_perl.c b/src/modules/perl/modperl_perl.c
index dfe4d36..bda988c 100644
--- a/src/modules/perl/modperl_perl.c
+++ b/src/modules/perl/modperl_perl.c
@@ -181,6 +181,8 @@
         }
     }
 
+    modperl_env_unload(perl);
+
     perl_destruct(perl);
 
     /* XXX: big bug in 5.6.1 fixed in 5.7.2+
diff --git a/t/response/TestModperl/env.pm b/t/response/TestModperl/env.pm
index 62eac81..ac057a9 100644
--- a/t/response/TestModperl/env.pm
+++ b/t/response/TestModperl/env.pm
@@ -15,7 +15,7 @@
 sub handler {
     my $r = shift;
 
-    plan $r, tests => 23 + keys(%ENV);
+    plan $r, tests => 23 + 3 * keys(%ENV);
 
     my $env = $r->subprocess_env;
 
@@ -75,6 +75,8 @@
     for my $key (sort keys %ENV) {
         eval { delete $ENV{$key}; };
         ok t_cmp($@, '', $key);
+        ok t_cmp($ENV{$key}, undef, "ENV{$key} is empty");
+        ok t_cmp($env->get($key), undef, "subprocess_env($key) is empty");
     }
 
     Apache2::Const::OK;