From 77e447a516a7f02bfdd2b8d774244b34e848162e Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Tue, 17 Mar 2026 14:52:43 +0000
Subject: [PATCH] lib: Remove configure-time QEMU

Remove the configure-time QEMU definition.  No longer initialize g->hv
= QEMU.  g->hv may now be NULL if the user does not explicitly either
call guestfs_set_hv or set LIBGUESTFS_HV.

Remove any assumptions in the code that g->hv is always non-NULL.

Fix one test that relied on the QEMU definition.
---
 lib/handle.c                   | 35 +++++++---------------------------
 tests/regressions/rhbz501893.c |  2 --
 2 files changed, 7 insertions(+), 30 deletions(-)

diff --git a/lib/handle.c b/lib/handle.c
index ab0e1289e..289fc4c81 100644
--- a/lib/handle.c
+++ b/lib/handle.c
@@ -118,17 +118,6 @@ guestfs_create_flags (unsigned flags, ...)
   g->path = strdup (GUESTFS_DEFAULT_PATH);
   if (!g->path) goto error;
 
-#ifdef QEMU
-  g->hv = strdup (QEMU);
-#else
-  /* configure --without-qemu, so set QEMU to something which will
-   * definitely fail.  The user is expected to override the hypervisor
-   * by setting an environment variable or calling set_hv.
-   */
-  g->hv = strdup ("false");
-#endif
-  if (!g->hv) goto error;
-
   /* Get program name. */
   if (STRPREFIX (getprogname (), "lt-"))
     /* Remove libtool (lt-*) prefix from short name. */
@@ -535,27 +524,17 @@ guestfs_impl_get_path (guestfs_h *g)
 int
 guestfs_impl_set_qemu (guestfs_h *g, const char *qemu)
 {
-  char *new_hv;
-
-  /* Only this deprecated set_qemu API supports using NULL as a
-   * parameter, to mean set it back to the default QEMU.  The new
-   * set_hv API does not allow callers to do this.
+  /* This deprecated API let you set qemu == NULL to mean "use the
+   * default qemu".  set_hv doesn't allow this, although maybe it
+   * should.
    */
   if (qemu == NULL) {
-#ifdef QEMU
-    new_hv = safe_strdup (g, QEMU);
-#else
-    error (g, _("configured --without-qemu so calling guestfs_set_qemu with qemu == NULL is an error"));
-    return -1;
-#endif
+    free (g->hv);
+    g->hv = NULL;
+    return 0;
   }
-  else
-    new_hv = safe_strdup (g, qemu);
 
-  free (g->hv);
-  g->hv = new_hv;
-
-  return 0;
+  return guestfs_impl_set_hv (g, qemu);
 }
 
 const char *
diff --git a/tests/regressions/rhbz501893.c b/tests/regressions/rhbz501893.c
index 4d8a3a71d..a2f0c5546 100644
--- a/tests/regressions/rhbz501893.c
+++ b/tests/regressions/rhbz501893.c
@@ -50,9 +50,7 @@ main (int argc, char *argv[])
 
   assert (guestfs_set_path (g, NULL) == 0);
   assert (guestfs_set_append (g, NULL) == 0);
-#ifdef QEMU
   assert (guestfs_set_qemu (g, NULL) == 0);
-#endif
 
   guestfs_close (g);
   exit (EXIT_SUCCESS);