curl: fix --upload-file . hangs if delay in STDIN

Attempt to unpause a busy read in the CURLOPT_XFERINFOFUNCTION.

When uploading from stdin in non-blocking mode, a delay in reading
the stream (EAGAIN) causes curl to pause sending data
(CURL_READFUNC_PAUSE).  Prior to this change, a busy read was
detected and unpaused only in the CURLOPT_WRITEFUNCTION handler.
This change performs the same busy read handling in a
CURLOPT_XFERINFOFUNCTION handler.

Fixes #2051
Closes #4599
Reported-by: bdry on github

1 files changed, 10 insertions, 1 deletions

diff --git a/src/tool_cb_prg.c b/src/tool_cb_prg.c
index a18827c8b..505ae751f 100644
--- a/src/tool_cb_prg.c
+++ b/src/tool_cb_prg.c
@@ -32,6 +32,7 @@
 #include "tool_cfgable.h"
 #include "tool_cb_prg.h"
 #include "tool_util.h"
+#include "tool_operate.h"
 
 #include "memdebug.h" /* keep this as LAST include */
 
@@ -121,7 +122,10 @@ int tool_progress_cb(void *clientp,
      and this new edition inherits some of his concepts. */
 
   struct timeval now = tvnow();
-  struct ProgressData *bar = (struct ProgressData *)clientp;
+  struct per_transfer *per = clientp;
+  struct OutStruct *outs = &per->outs;
+  struct OperationConfig *config = outs->config;
+  struct ProgressData *bar = &per->progressbar;
   curl_off_t total;
   curl_off_t point;
 
@@ -191,6 +195,11 @@ int tool_progress_cb(void *clientp,
   bar->prev = point;
   bar->prevtime = now;
 
+  if(config->readbusy) {
+    config->readbusy = FALSE;
+    curl_easy_pause(per->curl, CURLPAUSE_CONT);
+  }
+
   return 0;
 }