Make GPGME_DECRYPT_SESSION_HASH also work for gnupg 2.2.55

* src/engine-gpg.c (have_usable_session_hash): New.
(gpg_decrypt): Use here.

2 files changed, 23 insertions, 5 deletions

diff --git a/NEWS b/NEWS
index 36bbed9a..5064333a 100644
--- a/NEWS
+++ b/NEWS
@@ -1,19 +1,28 @@
-Noteworthy changes in version 2.0.2 (unreleased)   [C45/A0/R)]
+Noteworthy changes in version 2.1.0 (unreleased)   [C45/A0/R)]
 ------------------------------------------------
 
  * New flags "is_de_vs" and "beta_compliance" for encryption results.
    [T6702]
 
+ * New decryption flag GPGME_DECRYPT_SESSION_HASH and new field
+   session_hash in gpgme_decrypt_result_t.  For details see the gpg
+   option --show-session-key.  [rM63f18298d3]
+
  * New context flag "export-filter".  [T8033]
 
  * Extend the internal gpgsm_assuan_simple_command to consume all
    received lines.  This fixes a possible lockup introduced by the
    fix for T7759.  [T8187]
 
- * Interface changes relative to the 2.0.1 release:
+ * Interface changes relative to the 2.0.0 release:
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- gpgme_set_ctx_flag                    EXT: New flag 'export-filter'.
- gpgme_decrypt_result_t        EXT: New fields is_de_vs and beta_compliance.
+ gpgme_set_ctx_flag            EXT: New flag "export-filter".
+ gpgme_decrypt_result_t        EXT: New fields is_de_vs,
+                                    beta_compliance, and session_hash.
+ GPGME_DECRYPT_SESSION_HASH    NEW.
+
+ Release-info: https://dev.gnupg.org/T8237
+
 
 Noteworthy changes in version 2.0.1 (2025-09-23)   [C45/A0/R1]
 ------------------------------------------------
diff --git a/src/engine-gpg.c b/src/engine-gpg.c
index 8c4e38bf..eea97bc7 100644
--- a/src/engine-gpg.c
+++ b/src/engine-gpg.c
@@ -438,6 +438,15 @@ have_usable_gpgtar (engine_gpg_t gpg)
 
 
 static int
+have_usable_session_hash (engine_gpg_t gpg)
+{
+  return have_gpg_version (gpg, "2.5.19")
+         || (have_gpg_version (gpg, "2.2.55")
+             && !have_gpg_version (gpg, "2.3.0"));
+}
+
+
+static int
 have_option_proc_all_sigs (engine_gpg_t gpg)
 {
   static unsigned int flag;
@@ -1979,7 +1988,7 @@ gpg_decrypt (void *engine,
     err = add_arg (gpg, "--list-only");
 
   if (!err && (flags & GPGME_DECRYPT_SESSION_HASH)
-           && have_gpg_version (gpg, "2.5.19"))
+      && have_usable_session_hash (gpg))
     err = add_arg (gpg,
                    (flags & GPGME_DECRYPT_LISTONLY)? "--show-only-session-hash"
                    /* */                           : "--show-session-hash");