Initialize GPGME for signing

configure.ac

@@ -18,6 +18,12 @@ AC_PROG_INSTALL
 dnl Check for some non-ubiquitous functions
 ICP_CHECK_NOTCH_FUNCS
 
+dnl Check for GPGME
+AM_PATH_GPGME([],
+              [CFLAGS="$CFLAGS $GPGME_CFLAGS"
+               LIBS="$LIBS $GPGME_LIBS"],
+              [AC_MSG_ERROR([libgpgme not found])])
+
 dnl Output files
 AC_CONFIG_FILES([Makefile lib/Makefile src/Makefile])
 AC_OUTPUT

src/fmail.c

@@ -23,9 +23,12 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <getopt.h>
+#include <locale.h>
 #include <ctype.h>
 #include <time.h>
 
+#include <gpgme.h>
+
 #include <sbuffer.h>
 
 
@@ -43,6 +46,11 @@ Read a mail from standard input and send it.\n");
     -v, --version       Display the version message.\n\
 ");
 
+    puts("\
+  Cryptography options:\n\
+    -s, --sign          Sign the message.\n\
+");
+
     printf("Report bugs to <%s>.\n", PACKAGE_BUGREPORT);
 
     exit(status);
@@ -167,6 +175,27 @@ process_text_body(FILE *in, FILE *out)
 
 
 
+/* Signing stuff. */
+
+gpgme_ctx_t
+initialize_gpgme(void)
+{
+    gpgme_ctx_t ctx;
+    gpg_error_t gerr;
+
+    gpgme_check_version(NULL);
+    gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL));
+    gpgme_set_locale(NULL, LC_MESSAGES, setlocale(LC_MESSAGES, NULL));
+
+    if ( (gerr = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR )
+        errx(EXIT_FAILURE, "cannot initialize GPGME: %s",
+             gpgme_strerror(gerr));
+
+    return ctx;
+}
+
+
+
 /* Main function. */
 
 int
@@ -174,17 +203,22 @@ main(int argc, char *argv[])
 {
     char c;
     string_buffer_t *headers;
+    gpgme_ctx_t sign_ctx;
 
     struct option options[] = {
         { "help",    0, NULL, 'h' },
         { "version", 0, NULL, 'v' },
+        { "sign",    0, NULL, 's' },
         { NULL,      0, NULL, 0 }
     };
 
     setprogname(argv[0]);
+    setlocale(LC_ALL, "");
+
     headers = sb_new(0);
+    sign_ctx = NULL;
 
-    while ( (c = getopt_long(argc, argv, "hv",
+    while ( (c = getopt_long(argc, argv, "hvs",
                              options, NULL)) != -1 ) {
         switch ( c ) {
         case 'h':
@@ -198,6 +232,10 @@ main(int argc, char *argv[])
         case 'v':
             info();
             break;
+
+        case 's':
+            sign_ctx = initialize_gpgme();
+            break;
         }
     }
 
@@ -214,5 +252,9 @@ main(int argc, char *argv[])
     /* Write encoded body. */
     process_text_body(stdin, stdout);
 
+    /* Clean-up. */
+    if ( sign_ctx )
+        gpgme_release(sign_ctx);
+
     return EXIT_SUCCESS;
 }