added support for crappy libpcre c++ bindings

Added optional support for crappy google's c++ bindings. The bindings are
ridiculously googley, so I think, taking into account the amount of pcre
involved, I'll soon drop requirement for any bindings and will use libpcre
directly.

Signed-off-by: Michael Krelin <hacker@klever.net>

1 files changed, 47 insertions, 6 deletions

diff --git a/lib/consumer.cc b/lib/consumer.cc
index 8f66688..299b3bc 100644
--- a/lib/consumer.cc
+++ b/lib/consumer.cc
@@ -7,12 +7,19 @@
 #include <openssl/sha.h>
 #include <openssl/hmac.h>
 #include <curl/curl.h>
-#include <pcre++.h>
 
 #include <iostream>
 
 #include "config.h"
 
+#if defined(USE_LIBPCRECPP)
+# include <pcrecpp.h>
+#elif defined(USE_PCREPP)
+# include <pcre++.h>
+#else
+ /* internal implementation won't be built */
+#endif
+
 namespace opkele {
     using namespace std;
 
@@ -261,6 +268,7 @@ namespace opkele {
     }
 
     void consumer_t::retrieve_links(const string& url,string& server,string& delegate) {
+#if defined(USE_LIBPCRECPP) || defined(USE_PCREPP)
         server.erase();
         delegate.erase();
         curl_t curl = curl_easy_init();
@@ -278,17 +286,44 @@ namespace opkele {
         r = curl_easy_perform(curl);
         if(r && r!=CURLE_WRITE_ERROR)
             throw exception_curl(OPKELE_CP_ "failed to curl_easy_perform()",r);
-        pcrepp::Pcre bre("<body\\b",PCRE_CASELESS);
         // strip out everything past body
+        static const char *re_hdre = "<head[^>]*>",
+                     *re_lre = "<link\\b([^>]+)>",
+                     *re_rre = "\\brel=['\"]([^'\"]+)['\"]",
+                     *re_hre = "\\bhref=['\"]([^'\"]+)['\"]";
+#if defined(USE_LIBPCRECPP)
+        static pcrecpp::RE_Options ro(PCRE_CASELESS|PCRE_DOTALL);
+        static pcrecpp::RE
+            bre("<body\\b.*",ro), hdre(re_hdre,ro),
+            lre(re_lre,ro), rre(re_rre), hre(re_hre,ro);
+        bre.Replace("",&html);
+        pcrecpp::StringPiece hpiece(html);
+        if(!hdre.FindAndConsume(&hpiece))
+            throw bad_input(OPKELE_CP_ "failed to find head");
+        string attrs;
+        while(lre.FindAndConsume(&hpiece,&attrs)) {
+            pcrecpp::StringPiece rel, href;
+            if(!(rre.PartialMatch(attrs,&rel) && hre.PartialMatch(attrs,&href)))
+                continue;
+            if(rel=="openid.server") {
+                href.CopyToString(&server);
+                if(!delegate.empty())
+                    break;
+            }else if(rel=="openid.delegate") {
+                href.CopyToString(&delegate);
+                if(!server.empty())
+                    break;
+            }
+        }
+#elif defined(USE_PCREPP)
+        pcrepp::Pcre bre("<body\\b",PCRE_CASELESS);
         if(bre.search(html))
             html.erase(bre.get_match_start());
-        pcrepp::Pcre hdre("<head[^>]*>",PCRE_CASELESS);
+        pcrepp::Pcre hdre(re_hdre,PCRE_CASELESS);
         if(!hdre.search(html))
             throw bad_input(OPKELE_CP_ "failed to find head");
         html.erase(0,hdre.get_match_end()+1);
-        pcrepp::Pcre lre("<link\\b([^>]+)>",PCRE_CASELESS),
-            rre("\\brel=['\"]([^'\"]+)['\"]",PCRE_CASELESS),
-            hre("\\bhref=['\"]([^'\"]+)['\"]",PCRE_CASELESS);
+        pcrepp::Pcre lre(re_lre,PCRE_CASELESS), rre(re_rre,PCRE_CASELESS), hre(re_hre,PCRE_CASELESS);
         while(lre.search(html)) {
             string attrs = lre[0];
             html.erase(0,lre.get_match_end()+1);
@@ -304,8 +339,14 @@ namespace opkele {
                     break;
             }
         }
+#else
+        #error "I must have gone crazy"
+#endif
         if(server.empty())
             throw failed_assertion(OPKELE_CP_ "The location has no openid.server declaration");
+#else /* none of the RE bindings enabled */
+        throw not_implemented(OPKELE_CP_ "No internal implementation of retrieve_links were provided at compile-time");
+#endif
     }
 
     assoc_t consumer_t::find_assoc(const string& server) {