lib: turn state.referer into a struct bufref

Closes #19827

lib/easy.c

@@ -977,6 +977,7 @@ CURL *curl_easy_duphandle(CURL *d)
                  Curl_hash_str, curlx_str_key_compare, dupeasy_meta_freeentry);
   curlx_dyn_init(&outcurl->state.headerb, CURL_MAX_HTTP_HEADER);
   Curl_bufref_init(&outcurl->state.url);
+  Curl_bufref_init(&outcurl->state.referer);
   Curl_netrc_init(&outcurl->state.netrc);
 
   /* the connection pool is setup on demand */
@@ -1016,16 +1017,19 @@ CURL *curl_easy_duphandle(CURL *d)
   }
 #endif
 
-  if(Curl_bufref_ptr(&data->state.url))
+  if(Curl_bufref_ptr(&data->state.url)) {
     Curl_bufref_set(&outcurl->state.url,
                     curlx_strdup(Curl_bufref_ptr(&data->state.url)), 0,
                     curl_free);
-
-  if(data->state.referer) {
-    outcurl->state.referer = curlx_strdup(data->state.referer);
-    if(!outcurl->state.referer)
+    if(!Curl_bufref_ptr(&outcurl->state.url))
+      goto fail;
+  }
+  if(Curl_bufref_ptr(&data->state.referer)) {
+    Curl_bufref_set(&outcurl->state.referer,
+                    curlx_strdup(Curl_bufref_ptr(&data->state.referer)), 0,
+                    curl_free);
+    if(!Curl_bufref_ptr(&outcurl->state.referer))
       goto fail;
-    outcurl->state.referer_alloc = TRUE;
   }
 
   /* Reinitialize an SSL engine for the new handle

lib/getinfo.c

@@ -148,7 +148,7 @@ static CURLcode getinfo_char(struct Curl_easy *data, CURLINFO info,
     break;
   case CURLINFO_REFERER:
     /* Return the referrer header for this request, or NULL if unset */
-    *param_charp = data->state.referer;
+    *param_charp = Curl_bufref_ptr(&data->state.referer);
     break;
   case CURLINFO_PRIMARY_IP:
     /* Return the ip address of the most recent (primary) connection */

lib/http.c

@@ -1235,11 +1235,7 @@ CURLcode Curl_http_follow(struct Curl_easy *data, const char *newurl,
         /* We are asked to automatically set the previous URL as the referer
            when we get the next URL. We pick the ->url field, which may or may
            not be 100% correct */
-
-        if(data->state.referer_alloc) {
-          Curl_safefree(data->state.referer);
-          data->state.referer_alloc = FALSE;
-        }
+        Curl_bufref_free(&data->state.referer);
 
         /* Make a copy of the URL without credentials and fragment */
         u = curl_url();
@@ -1262,8 +1258,7 @@ CURLcode Curl_http_follow(struct Curl_easy *data, const char *newurl,
         if(uc || !referer)
           return CURLE_OUT_OF_MEMORY;
 
-        data->state.referer = referer;
-        data->state.referer_alloc = TRUE; /* yes, free this later */
+        Curl_bufref_set(&data->state.referer, referer, 0, curl_free);
       }
     }
   }
@@ -2867,8 +2862,10 @@ static CURLcode http_add_hd(struct Curl_easy *data,
 
   case H1_HD_REFERER:
     Curl_safefree(data->state.aptr.ref);
-    if(data->state.referer && !Curl_checkheaders(data, STRCONST("Referer")))
-      result = curlx_dyn_addf(req, "Referer: %s\r\n", data->state.referer);
+    if(Curl_bufref_ptr(&data->state.referer) &&
+       !Curl_checkheaders(data, STRCONST("Referer")))
+      result = curlx_dyn_addf(req, "Referer: %s\r\n",
+                              Curl_bufref_ptr(&data->state.referer));
     break;
 
 #ifndef CURL_DISABLE_PROXY

lib/rtsp.c

@@ -40,6 +40,7 @@
 #include "connect.h"
 #include "cfilters.h"
 #include "strdup.h"
+#include "bufref.h"
 #include "curlx/strparse.h"
 
 
@@ -536,9 +537,10 @@ static CURLcode rtsp_do(struct Curl_easy *data, bool *done)
 
   /* Referrer */
   Curl_safefree(data->state.aptr.ref);
-  if(data->state.referer && !Curl_checkheaders(data, STRCONST("Referer")))
-    data->state.aptr.ref = curl_maprintf("Referer: %s\r\n",
-                                         data->state.referer);
+  if(Curl_bufref_ptr(&data->state.referer) &&
+     !Curl_checkheaders(data, STRCONST("Referer")))
+    data->state.aptr.ref =
+      curl_maprintf("Referer: %s\r\n", Curl_bufref_ptr(&data->state.referer));
 
   p_referrer = data->state.aptr.ref;
 

lib/setopt.c

@@ -1754,12 +1754,8 @@ static CURLcode setopt_cptr(struct Curl_easy *data, CURLoption option,
     /*
      * String to set in the HTTP Referer: field.
      */
-    if(data->state.referer_alloc) {
-      Curl_safefree(data->state.referer);
-      data->state.referer_alloc = FALSE;
-    }
     result = Curl_setstropt(&s->str[STRING_SET_REFERER], ptr);
-    data->state.referer = s->str[STRING_SET_REFERER];
+    Curl_bufref_set(&data->state.referer, s->str[STRING_SET_REFERER], 0, NULL);
     break;
 
   case CURLOPT_USERAGENT:

lib/url.c

@@ -180,11 +180,7 @@ void Curl_freeset(struct Curl_easy *data)
     Curl_safefree(data->set.blobs[j]);
   }
 
-  if(data->state.referer_alloc) {
-    Curl_safefree(data->state.referer);
-    data->state.referer_alloc = FALSE;
-  }
-  data->state.referer = NULL;
+  Curl_bufref_free(&data->state.referer);
   Curl_bufref_free(&data->state.url);
 
   Curl_mime_cleanpart(&data->set.mimepost);
@@ -271,11 +267,7 @@ CURLcode Curl_close(struct Curl_easy **datap)
   Curl_safefree(data->state.first_host);
   Curl_ssl_free_certinfo(data);
 
-  if(data->state.referer_alloc) {
-    Curl_safefree(data->state.referer);
-    data->state.referer_alloc = FALSE;
-  }
-  data->state.referer = NULL;
+  Curl_bufref_free(&data->state.referer);
 
   up_free(data);
   curlx_dyn_free(&data->state.headerb);
@@ -514,6 +506,7 @@ CURLcode Curl_open(struct Curl_easy **curl)
                  Curl_hash_str, curlx_str_key_compare, easy_meta_freeentry);
   curlx_dyn_init(&data->state.headerb, CURL_MAX_HTTP_HEADER);
   Curl_bufref_init(&data->state.url);
+  Curl_bufref_init(&data->state.referer);
   Curl_req_init(&data->req);
   Curl_initinfo(data);
 #ifndef CURL_DISABLE_HTTP

lib/urldata.h

@@ -1027,7 +1027,7 @@ struct UrlState {
   CURLU *uh; /* URL handle for the current parsed URL */
   struct urlpieces up;
   struct bufref url;        /* work URL, initially copied from UserDefined */
-  char *referer;    /* referer string */
+  struct bufref referer;    /* referer string */
   struct curl_slist *resolve; /* set to point to the set.resolve list when
                                  this should be dealt with in pretransfer */
 #ifndef CURL_DISABLE_HTTP
@@ -1123,7 +1123,6 @@ struct UrlState {
 #ifdef CURL_LIST_ONLY_PROTOCOL
   BIT(list_only);      /* list directory contents */
 #endif
-  BIT(referer_alloc); /* referer string is malloc()ed */
   BIT(wildcard_resolve); /* Set to true if any resolve change is a wildcard */
   BIT(upload);         /* upload request */
   BIT(internal); /* internal: true if this easy handle was created for