HTTP: support multiple Content-Encodings

This is implemented as an output streaming stack of unencoders, the last
calling the client write procedure.

New test 230 checks this feature.

Bug: https://github.com/curl/curl/pull/2002
Reported-By: Daniel Bankhead

1 files changed, 4 insertions, 33 deletions

diff --git a/lib/transfer.c b/lib/transfer.c
index 937477670..8f15b1a15 100644
--- a/lib/transfer.c
+++ b/lib/transfer.c
@@ -779,48 +779,19 @@ static CURLcode readwrite_data(struct Curl_easy *data,
              in http_chunks.c.
              Make sure that ALL_CONTENT_ENCODINGS contains all the
              encodings handled here. */
-#ifdef HAVE_LIBZ
-          switch(conn->data->set.http_ce_skip ?
-                 IDENTITY : k->auto_decoding) {
-          case IDENTITY:
-#endif
-            /* This is the default when the server sends no
-               Content-Encoding header. See Curl_readwrite_init; the
-               memset() call initializes k->auto_decoding to zero. */
+          if(conn->data->set.http_ce_skip || !k->writer_stack) {
             if(!k->ignorebody) {
-
 #ifndef CURL_DISABLE_POP3
-              if(conn->handler->protocol&PROTO_FAMILY_POP3)
+              if(conn->handler->protocol & PROTO_FAMILY_POP3)
                 result = Curl_pop3_write(conn, k->str, nread);
               else
 #endif /* CURL_DISABLE_POP3 */
-
                 result = Curl_client_write(conn, CLIENTWRITE_BODY, k->str,
                                            nread);
             }
-#ifdef HAVE_LIBZ
-            break;
-
-          case DEFLATE:
-            /* Assume CLIENTWRITE_BODY; headers are not encoded. */
-            if(!k->ignorebody)
-              result = Curl_unencode_deflate_write(conn, k, nread);
-            break;
-
-          case GZIP:
-            /* Assume CLIENTWRITE_BODY; headers are not encoded. */
-            if(!k->ignorebody)
-              result = Curl_unencode_gzip_write(conn, k, nread);
-            break;
-
-          default:
-            failf(data, "Unrecognized content encoding type. "
-                  "libcurl understands `identity', `deflate' and `gzip' "
-                  "content encodings.");
-            result = CURLE_BAD_CONTENT_ENCODING;
-            break;
           }
-#endif
+          else
+            result = Curl_unencode_write(conn, k->writer_stack, k->str, nread);
         }
         k->badheader = HEADER_NORMAL; /* taken care of now */