dynbuf: introduce internal generic dynamic buffer functions

A common set of functions instead of many separate implementations for
creating buffers that can grow when appending data to them. Existing
functionality has been ported over.

In my early basic testing, the total number of allocations seem at
roughly the same amount as before, possibly a few less.

See docs/DYNBUF.md for a description of the API.

Closes #5300

1 files changed, 21 insertions, 21 deletions

diff --git a/lib/transfer.c b/lib/transfer.c
index b9581d7ad..cc13bae18 100644
--- a/lib/transfer.c
+++ b/lib/transfer.c
@@ -128,12 +128,13 @@ static size_t Curl_trailers_read(char *buffer, size_t size, size_t nitems,
                                  void *raw)
 {
   struct Curl_easy *data = (struct Curl_easy *)raw;
-  Curl_send_buffer *trailers_buf = data->state.trailers_buf;
-  size_t bytes_left = trailers_buf->size_used-data->state.trailers_bytes_sent;
+  struct dynbuf *trailers_buf = &data->state.trailers_buf;
+  size_t bytes_left = Curl_dyn_len(trailers_buf) -
+    data->state.trailers_bytes_sent;
   size_t to_copy = (size*nitems < bytes_left) ? size*nitems : bytes_left;
   if(to_copy) {
     memcpy(buffer,
-           &trailers_buf->buffer[data->state.trailers_bytes_sent],
+           Curl_dyn_ptr(trailers_buf) + data->state.trailers_bytes_sent,
            to_copy);
     data->state.trailers_bytes_sent += to_copy;
   }
@@ -143,8 +144,8 @@ static size_t Curl_trailers_read(char *buffer, size_t size, size_t nitems,
 static size_t Curl_trailers_left(void *raw)
 {
   struct Curl_easy *data = (struct Curl_easy *)raw;
-  Curl_send_buffer *trailers_buf = data->state.trailers_buf;
-  return trailers_buf->size_used - data->state.trailers_bytes_sent;
+  struct dynbuf *trailers_buf = &data->state.trailers_buf;
+  return Curl_dyn_len(trailers_buf) - data->state.trailers_bytes_sent;
 }
 #endif
 
@@ -186,11 +187,8 @@ CURLcode Curl_fillreadbuffer(struct connectdata *conn, size_t bytes,
     infof(data,
           "Moving trailers state machine from initialized to sending.\n");
     data->state.trailers_state = TRAILERS_SENDING;
-    data->state.trailers_buf = Curl_add_buffer_init();
-    if(!data->state.trailers_buf) {
-      failf(data, "Unable to allocate trailing headers buffer !");
-      return CURLE_OUT_OF_MEMORY;
-    }
+    Curl_dyn_init(&data->state.trailers_buf, DYN_TRAILERS);
+
     data->state.trailers_bytes_sent = 0;
     Curl_set_in_callback(data, true);
     trailers_ret_code = data->set.trailer_callback(&trailers,
@@ -206,7 +204,7 @@ CURLcode Curl_fillreadbuffer(struct connectdata *conn, size_t bytes,
       result = CURLE_ABORTED_BY_CALLBACK;
     }
     if(result) {
-      Curl_add_buffer_free(&data->state.trailers_buf);
+      Curl_dyn_free(&data->state.trailers_buf);
       curl_slist_free_all(trailers);
       return result;
     }
@@ -369,7 +367,7 @@ CURLcode Curl_fillreadbuffer(struct connectdata *conn, size_t bytes,
 #ifndef CURL_DISABLE_HTTP
     if(data->state.trailers_state == TRAILERS_SENDING &&
        !Curl_trailers_left(data)) {
-      Curl_add_buffer_free(&data->state.trailers_buf);
+      Curl_dyn_free(&data->state.trailers_buf);
       data->state.trailers_state = TRAILERS_DONE;
       data->set.trailer_data = NULL;
       data->set.trailer_callback = NULL;
@@ -770,8 +768,9 @@ static CURLcode readwrite_data(struct Curl_easy *data,
       /* pass data to the debug function before it gets "dechunked" */
       if(data->set.verbose) {
         if(k->badheader) {
-          Curl_debug(data, CURLINFO_DATA_IN, data->state.headerbuff,
-                     (size_t)k->hbuflen);
+          Curl_debug(data, CURLINFO_DATA_IN,
+                     Curl_dyn_ptr(&data->state.headerb),
+                     Curl_dyn_len(&data->state.headerb));
           if(k->badheader == HEADER_PARTHEADER)
             Curl_debug(data, CURLINFO_DATA_IN,
                        k->str, (size_t)nread);
@@ -822,9 +821,9 @@ static CURLcode readwrite_data(struct Curl_easy *data,
 
       /* Account for body content stored in the header buffer */
       if((k->badheader == HEADER_PARTHEADER) && !k->ignorebody) {
-        DEBUGF(infof(data, "Increasing bytecount by %zu from hbuflen\n",
-                     k->hbuflen));
-        k->bytecount += k->hbuflen;
+        size_t headlen = Curl_dyn_len(&data->state.headerb);
+        DEBUGF(infof(data, "Increasing bytecount by %zu\n", headlen));
+        k->bytecount += headlen;
       }
 
       if((-1 != k->maxdownload) &&
@@ -858,15 +857,16 @@ static CURLcode readwrite_data(struct Curl_easy *data,
         if(k->badheader && !k->ignorebody) {
           /* we parsed a piece of data wrongly assuming it was a header
              and now we output it as body instead */
+          size_t headlen = Curl_dyn_len(&data->state.headerb);
 
           /* Don't let excess data pollute body writes */
-          if(k->maxdownload == -1 || (curl_off_t)k->hbuflen <= k->maxdownload)
+          if(k->maxdownload == -1 || (curl_off_t)headlen <= k->maxdownload)
             result = Curl_client_write(conn, CLIENTWRITE_BODY,
-                                       data->state.headerbuff,
-                                       k->hbuflen);
+                                       Curl_dyn_ptr(&data->state.headerb),
+                                       headlen);
           else
             result = Curl_client_write(conn, CLIENTWRITE_BODY,
-                                       data->state.headerbuff,
+                                       Curl_dyn_ptr(&data->state.headerb),
                                        (size_t)k->maxdownload);
 
           if(result)