url: rename Curl_init_do => Curl_init_transfer

And correct some comments

Closes #22474

lib/multi.c

@@ -1751,7 +1751,7 @@ CURLMcode Curl_multi_add_perform(struct Curl_multi *multi,
 
     /* pass in NULL for 'conn' here since we do not want to init the
        connection, only this transfer */
-    result = Curl_init_do(data, NULL);
+    result = Curl_init_transfer(data, NULL);
     if(result) {
       Curl_multi_remove_handle(multi, data);
       return CURLM_INTERNAL_ERROR;

lib/url.c

@@ -1051,7 +1051,7 @@ static bool url_match_conn(struct connectdata *conn, void *userdata)
   if(!url_match_http_multiplex(conn, m))
     return FALSE;
   else if(m->wait_pipe)
-    /* we decided to wait on PIPELINING */
+    /* wait on multiplexing */
     return TRUE;
 
   if(!url_match_auth(conn, m))
@@ -2005,10 +2005,8 @@ static CURLcode url_create_needle(struct Curl_easy *data,
   CURLcode result = CURLE_OK;
   bool network_scheme = TRUE; /* almost all are */
 
-  /* First, split up the current URL in parts so that we can use the
-     parts for checking against the already present connections. In order
-     to not have to modify everything at once, we allocate a temporary
-     connection data struct and fill in for comparison purposes. */
+  /* Allocate a temporary connection data struct (needle) and fill in for
+     comparison purposes. */
   needle = allocate_conn(data);
   if(!needle) {
     result = CURLE_OUT_OF_MEMORY;
@@ -2279,7 +2277,7 @@ static CURLcode url_find_or_create_conn(struct Curl_easy *data)
       result = setup_range(data);
       if(!result) {
         Curl_xfer_setup_nop(data);
-        result = Curl_init_do(data, data->conn);
+        result = Curl_init_transfer(data, data->conn);
       }
     }
 
@@ -2404,7 +2402,7 @@ static CURLcode url_find_or_create_conn(struct Curl_easy *data)
   }
 
   /* Setup and init stuff before DO starts, in preparing for the transfer. */
-  result = Curl_init_do(data, data->conn);
+  result = Curl_init_transfer(data, data->conn);
   if(result)
     goto out;
 
@@ -2497,16 +2495,15 @@ out:
 }
 
 /*
- * Curl_init_do() inits the readwrite session. This is inited each time (in
- * the DO function before the protocol-specific DO functions are invoked) for
- * a transfer, sometimes multiple times on the same Curl_easy. Make sure
- * nothing in here depends on stuff that are setup dynamically for the
- * transfer.
+ * Curl_init_transfer() is called each time before the transfer starts - to
+ * prepare for a transfer, sometimes multiple times on the same Curl_easy.
+ * Make sure nothing in here depends on stuff that is setup dynamically for
+ * the transfer.
  *
  * Allow this function to get called with 'conn' set to NULL.
  */
 
-CURLcode Curl_init_do(struct Curl_easy *data, struct connectdata *conn)
+CURLcode Curl_init_transfer(struct Curl_easy *data, struct connectdata *conn)
 {
   CURLcode result;
 

lib/url.h

@@ -32,7 +32,7 @@
  * Prototypes for library-wide functions
  */
 
-CURLcode Curl_init_do(struct Curl_easy *data, struct connectdata *conn);
+CURLcode Curl_init_transfer(struct Curl_easy *data, struct connectdata *conn);
 CURLcode Curl_open(struct Curl_easy **curl);
 void Curl_init_userdefined(struct Curl_easy *data);
 

lib/urldata.h

@@ -703,9 +703,9 @@ struct UrlState {
                             417 response */
   BIT(use_range);
   BIT(rangestringalloc); /* the range string is malloc()'ed */
-  BIT(done); /* set to FALSE when Curl_init_do() is called and set to TRUE
-                when multi_done() is called, to prevent multi_done() to get
-                invoked twice when the multi interface is used. */
+  BIT(done); /* set to FALSE when Curl_init_transfer() is called and set to
+                TRUE when multi_done() is called, to prevent multi_done() from
+                being invoked twice. */
 #ifndef CURL_DISABLE_COOKIES
   BIT(cookie_engine);
 #endif

tests/unit/unit1620.c

@@ -92,8 +92,8 @@ static CURLcode test_unit1620(const char *arg)
   fail_unless(result == CURLE_URL_MALFORMAT,
               "Curl_connect() failed to return CURLE_URL_MALFORMAT");
 
-  result = Curl_init_do(empty, empty->conn);
-  fail_unless(result == CURLE_OK, "Curl_init_do() failed");
+  result = Curl_init_transfer(empty, empty->conn);
+  fail_unless(result == CURLE_OK, "Curl_init_transfer() failed");
 
   result = curl_easy_setopt((CURL *)empty, CURLOPT_NOBODY, 1L);
   fail_unless(result == CURLE_OK, "curl_easy_setopt(CURLOPT_NOBODY) failed");
@@ -103,8 +103,8 @@ static CURLcode test_unit1620(const char *arg)
     Curl_close(&empty);
   abort_unless(dupe, "curl_easy_duphandle() failed");
 
-  result = Curl_init_do(dupe, NULL);
-  fail_unless(result == CURLE_OK, "Curl_init_do() on duplicate failed");
+  result = Curl_init_transfer(dupe, NULL);
+  fail_unless(result == CURLE_OK, "Curl_init_transfer() on duplicate failed");
   fail_unless(dupe->req.no_body, "duplicate handle should keep no_body");
   fail_unless(dupe->state.httpreq == HTTPREQ_HEAD,
               "duplicate handle should use HTTPREQ_HEAD");