Copy regex unnamed captures to cloned subrequests.
Previously, unnamed regex captures matched in the parent request, were not
available in a cloned subrequest. Now 3 fields related to unnamed captures
are copied to a cloned subrequest: r->ncaptures, r->captures and
r->captures_data. Since r->captures cannot be changed by either request after
creating a clone, a new flag r->realloc_captures is introduced to force
reallocation of r->captures.
The issue was reported as a proxy_cache_background_update misbehavior in
http://mailman.nginx.org/pipermail/nginx/2018-December/057251.html.
diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index c57ec00..5e7152f 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -2386,6 +2386,14 @@
sr->phase_handler = r->phase_handler;
sr->write_event_handler = ngx_http_core_run_phases;
+#if (NGX_PCRE)
+ sr->ncaptures = r->ncaptures;
+ sr->captures = r->captures;
+ sr->captures_data = r->captures_data;
+ sr->realloc_captures = 1;
+ r->realloc_captures = 1;
+#endif
+
ngx_http_update_location_config(sr);
}
diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index 6bfff96..fce70ef 100644
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h
@@ -499,6 +499,10 @@
unsigned gzip_vary:1;
#endif
+#if (NGX_PCRE)
+ unsigned realloc_captures:1;
+#endif
+
unsigned proxy:1;
unsigned bypass_cache:1;
unsigned no_cache:1;
diff --git a/src/http/ngx_http_variables.c b/src/http/ngx_http_variables.c
index 2deb968..31321b2 100644
--- a/src/http/ngx_http_variables.c
+++ b/src/http/ngx_http_variables.c
@@ -2504,7 +2504,9 @@
if (re->ncaptures) {
len = cmcf->ncaptures;
- if (r->captures == NULL) {
+ if (r->captures == NULL || r->realloc_captures) {
+ r->realloc_captures = 0;
+
r->captures = ngx_palloc(r->pool, len * sizeof(int));
if (r->captures == NULL) {
return NGX_ERROR;