From f2b90b374fe7d8e111cd9f4a0e840fa55b91f4f6 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Thu, 11 Apr 2013 12:19:00 +0100
Subject: [PATCH] New APIs: set-program, get-program.

These set or get the program name in the handle.  Most programs
will never need to call this, since we set this, if possible,
using the glibc 'program_invocation_short_name(3)' feature.
---
 configure.ac           |  3 +++
 generator/actions.ml   | 26 ++++++++++++++++++++++++++
 src/guestfs-internal.h |  2 ++
 src/handle.c           | 34 +++++++++++++++++++++++++++++++++-
 test-tool/test-tool.c  |  1 +
 5 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 32cdaab77..f94a4117c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -272,6 +272,9 @@ AC_CHECK_MEMBER([struct stat.st_blksize],[
 dnl Define a C symbol for the host CPU architecture.
 AC_DEFINE_UNQUOTED([host_cpu],["$host_cpu"],[Host architecture.])
 
+dnl Check if libc has program_invocation_short_name.
+AC_CHECK_DECLS([program_invocation_short_name], [], [], [#include <errno.h>])
+
 dnl Headers.
 AC_CHECK_HEADERS([\
     attr/xattr.h \
diff --git a/generator/actions.ml b/generator/actions.ml
index 233590f59..2429789f2 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -2851,6 +2851,32 @@ In a graphical program, when the main thread is displaying a progress
 bar with a cancel button, wire up the cancel button to call this
 function." };
 
+  { defaults with
+    name = "set_program";
+    style = RErr, [String "program"], [];
+    fish_alias = ["program"];
+    blocking = false;
+    shortdesc = "set the program name";
+    longdesc = "\
+Set the program name.  This is an informative string which the
+main program may optionally set in the handle.
+
+When the handle is created, the program name in the handle is
+set to the basename from C<argv[0]>.  If that was not possible,
+it is set to the empty string (but never C<NULL>)." };
+
+  { defaults with
+    name = "get_program";
+    style = RConstString "program", [], [];
+    blocking = false;
+    tests = [
+      InitNone, Always, TestRun (
+        [["get_program"]])
+    ];
+    shortdesc = "get the program name";
+    longdesc = "\
+Get the program name.  See C<guestfs_set_program>." };
+
 ]
 
 (* daemon_functions are any functions which cause some action
diff --git a/src/guestfs-internal.h b/src/guestfs-internal.h
index 34d3bd78e..15326fc13 100644
--- a/src/guestfs-internal.h
+++ b/src/guestfs-internal.h
@@ -274,6 +274,8 @@ struct guestfs_h
 
   struct qemu_param *qemu_params; /* Extra qemu parameters. */
 
+  char *program;                /* Program name. */
+
   /* Array of drives added by add-drive* APIs.
    *
    * Before launch this list can be empty or contain some drives.
diff --git a/src/handle.c b/src/handle.c
index 5cc6e90c6..1c3fb9656 100644
--- a/src/handle.c
+++ b/src/handle.c
@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <string.h>
+#include <errno.h>
 
 #ifdef HAVE_LIBVIRT
 #include <libvirt/libvirt.h>
@@ -115,6 +116,19 @@ guestfs_create_flags (unsigned flags, ...)
   g->qemu = strdup (QEMU);
   if (!g->qemu) goto error;
 
+  /* Get program name. */
+#if defined(HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME) && \
+    HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME == 1
+  if (STRPREFIX (program_invocation_short_name, "lt-"))
+    /* Remove libtool (lt-*) prefix from short name. */
+    g->program = strdup (program_invocation_short_name + 3);
+  else
+    g->program = strdup (program_invocation_short_name);
+#else
+  g->program = strdup ("");
+#endif
+  if (!g->program) goto error;
+
   if (parse_backend (g, DEFAULT_BACKEND) == -1) {
     warning (g, _("libguestfs was built with an invalid default backend, using 'direct' instead"));
     g->backend = BACKEND_DIRECT;
@@ -137,12 +151,14 @@ guestfs_create_flags (unsigned flags, ...)
     gl_lock_unlock (handles_lock);
   }
 
-  debug (g, "create: flags = %u, handle = %p", flags, g);
+  debug (g, "create: flags = %u, handle = %p, program = %s",
+         flags, g, g->program);
 
   return g;
 
  error:
   free (g->backend_arg);
+  free (g->program);
   free (g->path);
   free (g->qemu);
   free (g->append);
@@ -338,6 +354,7 @@ guestfs_close (guestfs_h *g)
   free (g->int_tmpdir);
   free (g->int_cachedir);
   free (g->last_error);
+  free (g->program);
   free (g->path);
   free (g->qemu);
   free (g->append);
@@ -561,6 +578,21 @@ guestfs__get_network (guestfs_h *g)
   return g->enable_network;
 }
 
+int
+guestfs__set_program (guestfs_h *g, const char *program)
+{
+  free (g->program);
+  g->program = safe_strdup (g, program);
+
+  return 0;
+}
+
+const char *
+guestfs__get_program (guestfs_h *g)
+{
+  return g->program;
+}
+
 static int
 parse_backend (guestfs_h *g, const char *method)
 {
diff --git a/test-tool/test-tool.c b/test-tool/test-tool.c
index 3f4d36644..88d8aacd4 100644
--- a/test-tool/test-tool.c
+++ b/test-tool/test-tool.c
@@ -256,6 +256,7 @@ main (int argc, char *argv[])
   printf ("guestfs_get_network: %d\n", guestfs_get_network (g));
   printf ("guestfs_get_path: %s\n", guestfs_get_path (g) ? : "(null)");
   printf ("guestfs_get_pgroup: %d\n", guestfs_get_pgroup (g));
+  printf ("guestfs_get_program: %s\n", guestfs_get_program (g));
   printf ("guestfs_get_qemu: %s\n", guestfs_get_qemu (g));
   printf ("guestfs_get_recovery_proc: %d\n", guestfs_get_recovery_proc (g));
   printf ("guestfs_get_selinux: %d\n", guestfs_get_selinux (g));