Merge 6488715 into e551910

docs/libcurl/libcurl-errors.3

@@ -252,6 +252,8 @@ Failed to match the pinned key specified with \fICURLOPT_PINNEDPUBLICKEY(3)\fP.
 Status returned failure when asked with \fICURLOPT_SSL_VERIFYSTATUS(3)\fP.
 .IP "CURLE_HTTP2_STREAM (92)"
 Stream error in the HTTP/2 framing layer.
+.IP "CURLE_RECURSIVE_API_CALL (93)"
+An API function was called from inside a callback.
 .IP "CURLE_OBSOLETE*"
 These error codes will never be returned. They were used in an old libcurl
 version and are currently unused.
@@ -285,6 +287,8 @@ curl_multi_setopt() with unsupported option
 .IP "CURLM_ADDED_ALREADY (7)"
 An easy handle already added to a multi handle was attempted to get added a
 second time. (Added in 7.32.1)
+.IP "CURLM_RECURSIVE_API_CALL (8)"
+An API function was called from inside a callback.
 .SH "CURLSHcode"
 The "share" interface will return a CURLSHcode to indicate when an error has
 occurred.  Also consider \fIcurl_share_strerror(3)\fP.

docs/libcurl/symbols-in-versions

@@ -101,6 +101,7 @@ CURLE_QUOTE_ERROR               7.17.0
 CURLE_RANGE_ERROR               7.17.0
 CURLE_READ_ERROR                7.1
 CURLE_RECV_ERROR                7.10
+CURLE_RECURSIVE_API_CALL        7.59.0
 CURLE_REMOTE_ACCESS_DENIED      7.17.0
 CURLE_REMOTE_DISK_FULL          7.17.0
 CURLE_REMOTE_FILE_EXISTS        7.17.0
@@ -323,6 +324,7 @@ CURLM_CALL_MULTI_SOCKET         7.15.5
 CURLM_INTERNAL_ERROR            7.9.6
 CURLM_OK                        7.9.6
 CURLM_OUT_OF_MEMORY             7.9.6
+CURLM_RECURSIVE_API_CALL        7.59.0
 CURLM_UNKNOWN_OPTION            7.15.4
 CURLOPTTYPE_FUNCTIONPOINT       7.1
 CURLOPTTYPE_LONG                7.1

include/curl/curl.h

@@ -577,6 +577,8 @@ typedef enum {
   CURLE_SSL_INVALIDCERTSTATUS,   /* 91 - invalid certificate status */
   CURLE_HTTP2_STREAM,            /* 92 - stream error in HTTP/2 framing layer
                                     */
+  CURLE_RECURSIVE_API_CALL,      /* 93 - an api function was called from
+                                    inside a callback */
   CURL_LAST /* never use! */
 } CURLcode;
 

include/curl/multi.h

@@ -70,6 +70,8 @@ typedef enum {
   CURLM_UNKNOWN_OPTION,  /* curl_multi_setopt() with unsupported option */
   CURLM_ADDED_ALREADY,   /* an easy handle already added to a multi handle was
                             attempted to get added - again */
+  CURLM_RECURSIVE_API_CALL, /* an api function was called from inside a
+                               callback */
   CURLM_LAST
 } CURLMcode;
 

lib/connect.c

@@ -1033,9 +1033,11 @@ static CURLcode singleipconnect(struct connectdata *conn,
 
   if(data->set.fsockopt) {
     /* activate callback for setting socket options */
+    Curl_set_in_callback(data, true);
     error = data->set.fsockopt(data->set.sockopt_client,
                                sockfd,
                                CURLSOCKTYPE_IPCXN);
+    Curl_set_in_callback(data, false);
 
     if(error == CURL_SOCKOPT_ALREADY_CONNECTED)
       isconnected = TRUE;
@@ -1311,8 +1313,12 @@ int Curl_closesocket(struct connectdata *conn,
          status */
       conn->sock_accepted[SECONDARYSOCKET] = FALSE;
     else {
+      int rc;
       Curl_multi_closed(conn, sock);
-      return conn->fclosesocket(conn->closesocket_client, sock);
+      Curl_set_in_callback(conn->data, true);
+      rc = conn->fclosesocket(conn->closesocket_client, sock);
+      Curl_set_in_callback(conn->data, false);
+      return rc;
     }
   }
 
@@ -1363,7 +1369,7 @@ CURLcode Curl_socket(struct connectdata *conn,
      addr->addrlen = sizeof(struct Curl_sockaddr_storage);
   memcpy(&addr->sa_addr, ai->ai_addr, addr->addrlen);
 
-  if(data->set.fopensocket)
+  if(data->set.fopensocket) {
    /*
     * If the opensocket callback is set, all the destination address
     * information is passed to the callback. Depending on this information the
@@ -1373,9 +1379,12 @@ CURLcode Curl_socket(struct connectdata *conn,
     * might have been changed and this 'new' address will actually be used
     * here to connect.
     */
+    Curl_set_in_callback(data, true);
     *sockfd = data->set.fopensocket(data->set.opensocket_client,
                                     CURLSOCKTYPE_IPCXN,
                                     (struct curl_sockaddr *)addr);
+    Curl_set_in_callback(data, false);
+  }
   else
     /* opensocket callback not set, so simply create the socket now */
     *sockfd = socket(addr->family, addr->socktype, addr->protocol);

lib/easy.c

@@ -61,6 +61,7 @@
 #include "strdup.h"
 #include "progress.h"
 #include "easyif.h"
+#include "multiif.h"
 #include "select.h"
 #include "sendf.h" /* for failf function prototype */
 #include "connect.h" /* for Curl_getconnectinfo */
@@ -761,6 +762,9 @@ static CURLcode easy_perform(struct Curl_easy *data, bool events)
     data->multi_easy = multi;
   }
 
+  if(multi->in_callback)
+    return CURLE_RECURSIVE_API_CALL;
+
   /* Copy the MAXCONNECTS option to the multi handle */
   curl_multi_setopt(multi, CURLMOPT_MAXCONNECTS, data->set.maxconnects);
 
@@ -1030,6 +1034,9 @@ void curl_easy_reset(struct Curl_easy *data)
  * the pausing, you may get your write callback called at this point.
  *
  * Action is a bitmask consisting of CURLPAUSE_* bits in curl/curl.h
+ *
+ * NOTE: This is one of few API functions that are allowed to be called from
+ * within a callback.
  */
 CURLcode curl_easy_pause(struct Curl_easy *data, int action)
 {
@@ -1134,6 +1141,9 @@ CURLcode curl_easy_recv(struct Curl_easy *data, void *buffer, size_t buflen,
   ssize_t n1;
   struct connectdata *c;
 
+  if(Curl_is_in_callback(data))
+    return CURLE_RECURSIVE_API_CALL;
+
   result = easy_connection(data, &sfd, &c);
   if(result)
     return result;
@@ -1161,6 +1171,9 @@ CURLcode curl_easy_send(struct Curl_easy *data, const void *buffer,
   ssize_t n1;
   struct connectdata *c = NULL;
 
+  if(Curl_is_in_callback(data))
+    return CURLE_RECURSIVE_API_CALL;
+
   result = easy_connection(data, &sfd, &c);
   if(result)
     return result;

lib/ftp.c

@@ -311,9 +311,11 @@ static CURLcode AcceptServerConnect(struct connectdata *conn)
     int error = 0;
 
     /* activate callback for setting socket options */
+    Curl_set_in_callback(data, true);
     error = data->set.fsockopt(data->set.sockopt_client,
                                s,
                                CURLSOCKTYPE_ACCEPT);
+    Curl_set_in_callback(data, false);
 
     if(error) {
       close_secondarysocket(conn);
@@ -1616,8 +1618,10 @@ static CURLcode ftp_state_ul_setup(struct connectdata *conn,
 
     /* Let's read off the proper amount of bytes from the input. */
     if(conn->seek_func) {
+      Curl_set_in_callback(data, true);
       seekerr = conn->seek_func(conn->seek_client, data->state.resume_from,
                                 SEEK_SET);
+      Curl_set_in_callback(data, true);
     }
 
     if(seekerr != CURL_SEEKFUNC_OK) {
@@ -3181,7 +3185,9 @@ static CURLcode ftp_done(struct connectdata *conn, CURLcode status,
 
   if(data->state.wildcardmatch) {
     if(data->set.chunk_end && ftpc->file) {
+      Curl_set_in_callback(data, true);
       data->set.chunk_end(data->wildcard.customptr);
+      Curl_set_in_callback(data, false);
     }
     ftpc->known_filesize = -1;
   }
@@ -3834,8 +3840,11 @@ static CURLcode wc_statemach(struct connectdata *conn)
 
     infof(conn->data, "Wildcard - START of \"%s\"\n", finfo->filename);
     if(conn->data->set.chunk_bgn) {
-      long userresponse = conn->data->set.chunk_bgn(
+      long userresponse;
+      Curl_set_in_callback(conn->data, true);
+      userresponse = conn->data->set.chunk_bgn(
         finfo, wildcard->customptr, (int)wildcard->filelist.size);
+      Curl_set_in_callback(conn->data, false);
       switch(userresponse) {
       case CURL_CHUNK_BGN_FUNC_SKIP:
         infof(conn->data, "Wildcard - \"%s\" skipped by user\n",
@@ -3871,8 +3880,11 @@ static CURLcode wc_statemach(struct connectdata *conn)
   } break;
 
   case CURLWC_SKIP: {
-    if(conn->data->set.chunk_end)
+    if(conn->data->set.chunk_end) {
+      Curl_set_in_callback(conn->data, true);
       conn->data->set.chunk_end(conn->data->wildcard.customptr);
+      Curl_set_in_callback(conn->data, false);
+    }
     Curl_llist_remove(&wildcard->filelist, wildcard->filelist.head, NULL);
     wildcard->state = (wildcard->filelist.size == 0) ?
                       CURLWC_CLEAN : CURLWC_DOWNLOADING;

lib/ftplistparser.c

@@ -49,6 +49,7 @@
 #include "ftplistparser.h"
 #include "curl_fnmatch.h"
 #include "curl_memory.h"
+#include "multiif.h"
 /* The last #include file should be: */
 #include "memdebug.h"
 
@@ -294,6 +295,7 @@ static CURLcode ftp_pl_insert_finfo(struct connectdata *conn,
     compare = Curl_fnmatch;
 
   /* filter pattern-corresponding filenames */
+  Curl_set_in_callback(conn->data, true);
   if(compare(conn->data->set.fnmatch_data, wc->pattern,
              finfo->filename) == 0) {
     /* discard symlink which is containing multiple " -> " */
@@ -305,6 +307,7 @@ static CURLcode ftp_pl_insert_finfo(struct connectdata *conn,
   else {
     add = FALSE;
   }
+  Curl_set_in_callback(conn->data, false);
 
   if(add) {
     Curl_llist_insert_next(llist, llist->tail, finfo, &infop->list);

lib/http.c

@@ -2191,8 +2191,10 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
       /* Now, let's read off the proper amount of bytes from the
          input. */
       if(conn->seek_func) {
+        Curl_set_in_callback(data, true);
         seekerr = conn->seek_func(conn->seek_client, data->state.resume_from,
                                   SEEK_SET);
+        Curl_set_in_callback(data, false);
       }
 
       if(seekerr != CURL_SEEKFUNC_OK) {

lib/http2.c

@@ -464,9 +464,11 @@ static int push_promise(struct Curl_easy *data,
       goto fail;
     }
 
+    Curl_set_in_callback(data, true);
     rv = data->multi->push_cb(data, newhandle,
                               stream->push_headers_used, &heads,
                               data->multi->push_userp);
+    Curl_set_in_callback(data, false);
 
     /* free the headers again */
     for(i = 0; i<stream->push_headers_used; i++)