[gnumeric] lpsolve: check that the program is linear before writing bogus program

[Morten Welinder <mortenw src gnome org>]

commit 767ef346a6b21365abb7b62dde515a0a9a1792e7
Author: Morten Welinder <terra gnome org>
Date:   Tue Jan 6 22:10:55 2015 -0500

    lpsolve: check that the program is linear before writing bogus program

 plugins/lpsolve/ChangeLog       |    5 +++++
 plugins/lpsolve/lpsolve-write.c |   10 ++++++++++
 2 files changed, 15 insertions(+), 0 deletions(-)
---
diff --git a/plugins/lpsolve/ChangeLog b/plugins/lpsolve/ChangeLog
index 853acd6..9a3b419 100644
--- a/plugins/lpsolve/ChangeLog
+++ b/plugins/lpsolve/ChangeLog
@@ -1,3 +1,8 @@
+2015-01-06  Morten Welinder  <terra gnome org>
+
+       * lpsolve-write.c (lpsolve_create_program): Fail unless the
+       problem is linear.
+
 2014-09-25  Morten Welinder <terra gnome org>
 
        * Release 1.12.18
diff --git a/plugins/lpsolve/lpsolve-write.c b/plugins/lpsolve/lpsolve-write.c
index d156f7f..863d34c 100644
--- a/plugins/lpsolve/lpsolve-write.c
+++ b/plugins/lpsolve/lpsolve-write.c
@@ -182,6 +182,16 @@ lpsolve_create_program (Sheet *sheet, GOIOContext *io_context,
 
        /* ---------------------------------------- */
 
+       if (sp->options.model_type != GNM_SOLVER_LP) {
+               g_set_error (err,
+                            go_error_invalid (),
+                            0,
+                            _("Only linear programs are handled."));
+               goto fail;
+       }
+
+       /* ---------------------------------------- */
+
        progress = 2;
        if (sp->options.assume_non_negative) progress++;
        if (sp->options.assume_discrete) progress++;