From 995b1b62add89b437cb51bb7e15a35c265e188b3 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Fri, 28 Jul 2023 14:33:03 +0100
Subject: [PATCH] pool: Add outline get_ready and after_fork functions

In a forthcoming commit we will need to create a multi handle and a
background thread, requiring use of the .get_ready (for multi) and
.after_fork (for the thread) plugin methods.  This commit removes the
empty load_pool function and adds pool_get_ready and pool_after_fork,
and the associated machinery in curl.c.

This commit on its own does nothing, future commits will fill in these
functions with useful work.

Reviewed-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 4075a499115a9e12ea74c4838fe00a7d680de2a1)
---
 plugins/curl/curl.c     | 14 +++++++++++++-
 plugins/curl/curldefs.h |  3 ++-
 plugins/curl/pool.c     | 12 +++++++++---
 3 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/plugins/curl/curl.c b/plugins/curl/curl.c
index 72971093..4e727b86 100644
--- a/plugins/curl/curl.c
+++ b/plugins/curl/curl.c
@@ -67,8 +67,18 @@ curl_load (void)
     nbdkit_error ("libcurl initialization failed: %d", (int) r);
     exit (EXIT_FAILURE);
   }
+}
 
-  load_pool ();
+int
+curl_get_ready (void)
+{
+  return pool_get_ready ();
+}
+
+int
+curl_after_fork (void)
+{
+  return pool_after_fork ();
 }
 
 static void
@@ -249,6 +259,8 @@ static struct nbdkit_plugin plugin = {
    */
   //.config_help       = curl_config_help,
   .magic_config_key  = "url",
+  .get_ready         = curl_get_ready,
+  .after_fork        = curl_after_fork,
   .open              = curl_open,
   .close             = curl_close,
   .get_size          = curl_get_size,
diff --git a/plugins/curl/curldefs.h b/plugins/curl/curldefs.h
index cab4a6b1..939c8d37 100644
--- a/plugins/curl/curldefs.h
+++ b/plugins/curl/curldefs.h
@@ -124,7 +124,8 @@ extern struct curl_handle *allocate_handle (void);
 extern void free_handle (struct curl_handle *);
 
 /* pool.c */
-extern void load_pool (void);
+extern int pool_get_ready (void);
+extern int pool_after_fork (void);
 extern void pool_unload (void);
 extern struct curl_handle *get_handle (void);
 extern void put_handle (struct curl_handle *ch);
diff --git a/plugins/curl/pool.c b/plugins/curl/pool.c
index 50a623a4..eb2d330e 100644
--- a/plugins/curl/pool.c
+++ b/plugins/curl/pool.c
@@ -78,10 +78,16 @@ static curl_handle_list curl_handles = empty_vector;
 static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
 static size_t in_use = 0, waiting = 0;
 
-/* Initialize pool structures. */
-void
-load_pool (void)
+int
+pool_get_ready (void)
 {
+  return 0;
+}
+
+int
+pool_after_fork (void)
+{
+  return 0;
 }
 
 /* Close and free all handles in the pool. */
-- 
2.39.3