[gmime] Check for GnuPG >= 2.1 and set a custom gpg.conf property if so

[Jeffrey Stedfast <fejj src gnome org>]

commit 95daa53b2a76c0aa7ab4cb8d62c606ffd6a431ce
Author: Jeffrey Stedfast <jestedfa microsoft com>
Date:   Fri Dec 2 19:05:31 2016 -0500

    Check for GnuPG >= 2.1 and set a custom gpg.conf property if so
    
    Thanks to Daniel Kahn Gillmor for this patch

 tests/testsuite.c |   59 ++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 58 insertions(+), 1 deletions(-)
---
diff --git a/tests/testsuite.c b/tests/testsuite.c
index fa4fd9c..103606b 100644
--- a/tests/testsuite.c
+++ b/tests/testsuite.c
@@ -27,6 +27,10 @@
 #ifdef ENABLE_THREADS
 #include <pthread.h>
 #endif
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
 
 #include "testsuite.h"
 
@@ -346,9 +350,46 @@ g_throw (Exception *ex)
        longjmp (env->env, 1);
 }
 
+static int
+is_gpg_modern (void)
+{
+       const char vheader[] = "gpg (GnuPG) ";
+       char *vstring;
+       size_t vlen;
+       FILE *vpipe;
+       int ret;
+       
+       if ((vpipe = popen ("gpg --version", "r")) == NULL)
+               return 0;
+       
+       vlen = 0;
+       vstring = NULL;
+       
+       if (getline (&vstring, &vlen, vpipe) == -1) {
+               pclose (vpipe);
+               return 0;
+       }
+       
+       pclose (vpipe);
+       
+       if (strncmp (vstring, vheader, sizeof (vheader) - 1))
+               return 0;
+       
+       ret = (vstring[sizeof (vheader) - 1] > '2') ||
+               (vstring[sizeof (vheader) - 1] == '2' &&
+                vstring[sizeof (vheader)] == '.' &&
+                vstring[sizeof (vheader) + 1] >= '1');
+       
+       free (vstring);
+       
+       return ret;
+}
+
 int
 testsuite_setup_gpghome (void)
 {
+       const char directive[] = "pinentry-mode loopback\n";
+       
        /* reset .gnupg config directory */
        if (system ("/bin/rm -rf ./tmp") != 0)
                return EXIT_FAILURE;
@@ -356,7 +397,7 @@ testsuite_setup_gpghome (void)
                return EXIT_FAILURE;
        
        g_setenv ("GNUPGHOME", "./tmp/.gnupg", 1);
-
+       
        /* disable environment variables that gpg-agent uses for pinentry */
        g_unsetenv ("DBUS_SESSION_BUS_ADDRESS");
        g_unsetenv ("DISPLAY");
@@ -365,6 +406,22 @@ testsuite_setup_gpghome (void)
        if (system ("gpg --list-keys > /dev/null 2>&1") != 0)
                return EXIT_FAILURE;
        
+       if (is_gpg_modern ()) {
+               FILE *fp;
+               
+               if ((fp = fopen ("./tmp/.gnupg/gpg.conf", "w")) == NULL)
+                       return EXIT_FAILURE;
+               
+               if (fwrite (directive, sizeof (directive) - 1, 1, fp) != 1) {
+                       fclose (fp);
+                       return EXIT_FAILURE;
+               }
+               
+               if (fclose (fp))
+                       return EXIT_FAILURE;
+       }
+       
+       
        return EXIT_SUCCESS;
 }