Add -ciphers flag to enc command

Don't print the full list of ciphers as part of the -help output.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

apps/enc.c

@@ -34,6 +34,7 @@ static void show_ciphers(const OBJ_NAME *name, void *bio_);
 
 typedef enum OPTION_choice {
     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
+    OPT_LIST,
     OPT_E, OPT_IN, OPT_OUT, OPT_PASS, OPT_ENGINE, OPT_D, OPT_P, OPT_V,
     OPT_NOPAD, OPT_SALT, OPT_NOSALT, OPT_DEBUG, OPT_UPPER_P, OPT_UPPER_A,
     OPT_A, OPT_Z, OPT_BUFSIZE, OPT_K, OPT_KFILE, OPT_UPPER_K, OPT_NONE,
@@ -42,6 +43,7 @@ typedef enum OPTION_choice {
 
 OPTIONS enc_options[] = {
     {"help", OPT_HELP, '-', "Display this summary"},
+    {"ciphers", OPT_LIST, '-', "List ciphers"},
     {"in", OPT_IN, '<', "Input file"},
     {"out", OPT_OUT, '>', "Output file"},
     {"pass", OPT_PASS, 's', "Passphrase source"},
@@ -129,7 +131,9 @@ int enc_main(int argc, char **argv)
         case OPT_HELP:
             opt_help(enc_options);
             ret = 0;
-            BIO_printf(bio_err, "Cipher Types\n");
+            goto end;
+        case OPT_LIST:
+            BIO_printf(bio_err, "Supported ciphers:\n");
             OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH,
                                    show_ciphers, bio_err);
             BIO_printf(bio_err, "\n");

doc/apps/enc.pod

@@ -8,6 +8,7 @@ enc - symmetric cipher routines
 
 B<openssl enc -ciphername>
 [B<-help>]
+[B<-ciphers>]
 [B<-in filename>]
 [B<-out filename>]
 [B<-pass arg>]
@@ -47,6 +48,10 @@ either by itself or in addition to the encryption or decryption.
 
 Print out a usage message.
 
+=item B<-ciphers>
+
+List all supported ciphers.
+
 =item B<-in filename>
 
 the input filename, standard input by default.