Fixup demo exit status magic numbers

The demo code is quite often block copied for new demos,
so this PR changes demos to use EXIT_SUCCESS & EXIT_FAILURE
instead of using 0 and 1.
Internal functions use the normal notation of 0 = error, 1 = success,
but the value returned by main() must use EXIT_SUCCESS and EXIT_FAILURE.

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>

(cherry picked from commit 09ff84b)

Reviewed-by: Hugo Landau <hlandau@openssl.org>
(Merged from #22728)

demos/bio/client-arg.c

@@ -22,6 +22,7 @@ int main(int argc, char **argv)
     char **args = argv + 1;
     const char *connect_str = "localhost:4433";
     int nargs = argc - 1;
+    int ret = EXIT_FAILURE;
 
     ctx = SSL_CTX_new(TLS_client_method());
     cctx = SSL_CONF_CTX_new();
@@ -100,9 +101,10 @@ int main(int argc, char **argv)
             break;
         BIO_write(out, tmpbuf, len);
     }
+    ret = EXIT_SUCCESS;
  end:
     SSL_CONF_CTX_free(cctx);
     BIO_free_all(sbio);
     BIO_free(out);
-    return 0;
+    return ret;
 }

demos/bio/client-conf.c

@@ -25,6 +25,7 @@ int main(int argc, char **argv)
     CONF_VALUE *cnf;
     const char *connect_str = "localhost:4433";
     long errline = -1;
+    int ret = EXIT_FAILURE;
 
     conf = NCONF_new(NULL);
 
@@ -108,10 +109,12 @@ int main(int argc, char **argv)
             break;
         BIO_write(out, tmpbuf, len);
     }
+    ret = EXIT_SUCCESS;
+
  end:
     SSL_CONF_CTX_free(cctx);
     BIO_free_all(sbio);
     BIO_free(out);
     NCONF_free(conf);
-    return 0;
+    return ret;
 }

demos/cipher/aesccm.c

@@ -229,10 +229,10 @@ int aes_ccm_decrypt(void)
 int main(int argc, char **argv)
 {
     if (!aes_ccm_encrypt())
-        return 1;
+        return EXIT_FAILURE;
 
     if (!aes_ccm_decrypt())
-        return 1;
+        return EXIT_FAILURE;
 
-    return 0;
+    return EXIT_SUCCESS;
 }

demos/cipher/aesgcm.c

@@ -219,10 +219,10 @@ int aes_gcm_decrypt(void)
 int main(int argc, char **argv)
 {
     if (!aes_gcm_encrypt())
-        return 1;
+        return EXIT_FAILURE;
 
     if (!aes_gcm_decrypt())
-        return 1;
+        return EXIT_FAILURE;
 
-    return 0;
+    return EXIT_SUCCESS;
 }

demos/cipher/aeskeywrap.c

@@ -171,11 +171,10 @@ int aes_wrap_decrypt(void)
 int main(int argc, char **argv)
 {
     if (!aes_wrap_encrypt())
-       return 1;
+       return EXIT_FAILURE;
 
     if (!aes_wrap_decrypt())
-        return 1;
+        return EXIT_FAILURE;
 
-    return 0;
+    return EXIT_SUCCESS;
 }
-

demos/cipher/ariacbc.c

@@ -169,10 +169,10 @@ int aria_cbc_decrypt(void)
 int main(int argc, char **argv)
 {
     if (!aria_cbc_encrypt())
-       return 1;
+        return EXIT_FAILURE;
 
     if (!aria_cbc_decrypt())
-        return 1;
+        return EXIT_FAILURE;
 
-    return 0;
+    return EXIT_SUCCESS;
 }

demos/cms/cms_comp.c

@@ -16,7 +16,7 @@ int main(int argc, char **argv)
 {
     BIO *in = NULL, *out = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     /*
      * On OpenSSL 1.0.0+ only:
@@ -48,11 +48,11 @@ int main(int argc, char **argv)
     if (!SMIME_write_CMS(out, cms, in, flags))
         goto err;
 
-    ret = 0;
+    ret = EXIT_SUCCESS;
 
  err:
 
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Compressing Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_ddec.c

@@ -21,7 +21,7 @@ int main(int argc, char **argv)
     X509 *rcert = NULL;
     EVP_PKEY *rkey = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     OpenSSL_add_all_algorithms();
     ERR_load_crypto_strings();
@@ -68,11 +68,11 @@ int main(int argc, char **argv)
     if (!CMS_decrypt(cms, rkey, rcert, dcont, out, 0))
         goto err;
 
-    ret = 0;
+    ret = EXIT_SUCCESS;
 
  err:
 
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Decrypting Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_dec.c

@@ -18,7 +18,7 @@ int main(int argc, char **argv)
     X509 *rcert = NULL;
     EVP_PKEY *rkey = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     OpenSSL_add_all_algorithms();
     ERR_load_crypto_strings();
@@ -59,11 +59,10 @@ int main(int argc, char **argv)
     if (!CMS_decrypt(cms, rkey, rcert, NULL, out, 0))
         goto err;
 
-    ret = 0;
+    ret = EXIT_SUCCESS;
 
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Decrypting Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_denc.c

@@ -21,7 +21,7 @@ int main(int argc, char **argv)
     X509 *rcert = NULL;
     STACK_OF(X509) *recips = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     int flags = CMS_STREAM | CMS_DETACHED;
 
@@ -77,11 +77,9 @@ int main(int argc, char **argv)
     if (!PEM_write_bio_CMS(out, cms))
         goto err;
 
-    ret = 0;
-
+    ret = EXIT_SUCCESS;
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Encrypting Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_enc.c

@@ -18,7 +18,7 @@ int main(int argc, char **argv)
     X509 *rcert = NULL;
     STACK_OF(X509) *recips = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     /*
      * On OpenSSL 1.0.0 and later only:
@@ -73,11 +73,9 @@ int main(int argc, char **argv)
     if (!SMIME_write_CMS(out, cms, in, flags))
         goto err;
 
-    ret = 0;
-
+    ret = EXIT_SUCCESS;
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Encrypting Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_sign.c

@@ -18,7 +18,7 @@ int main(int argc, char **argv)
     X509 *scert = NULL;
     EVP_PKEY *skey = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     /*
      * For simple S/MIME signing use CMS_DETACHED. On OpenSSL 1.0.0 only: for
@@ -69,11 +69,9 @@ int main(int argc, char **argv)
     if (!SMIME_write_CMS(out, cms, in, flags))
         goto err;
 
-    ret = 0;
-
+    ret = EXIT_SUCCESS;
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Signing Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_sign2.c

@@ -18,7 +18,7 @@ int main(int argc, char **argv)
     X509 *scert = NULL, *scert2 = NULL;
     EVP_PKEY *skey = NULL, *skey2 = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     OpenSSL_add_all_algorithms();
     ERR_load_crypto_strings();
@@ -77,11 +77,9 @@ int main(int argc, char **argv)
     if (!SMIME_write_CMS(out, cms, in, CMS_STREAM))
         goto err;
 
-    ret = 0;
-
+    ret = EXIT_SUCCESS;
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Signing Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_uncomp.c

@@ -16,7 +16,7 @@ int main(int argc, char **argv)
 {
     BIO *in = NULL, *out = NULL;
     CMS_ContentInfo *cms = NULL;
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     OpenSSL_add_all_algorithms();
     ERR_load_crypto_strings();
@@ -42,11 +42,9 @@ int main(int argc, char **argv)
     if (!CMS_uncompress(cms, out, NULL, 0))
         goto err;
 
-    ret = 0;
-
+    ret = EXIT_SUCCESS;
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Uncompressing Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/cms/cms_ver.c

@@ -18,8 +18,7 @@ int main(int argc, char **argv)
     X509_STORE *st = NULL;
     X509 *cacert = NULL;
     CMS_ContentInfo *cms = NULL;
-
-    int ret = 1;
+    int ret = EXIT_FAILURE;
 
     OpenSSL_add_all_algorithms();
     ERR_load_crypto_strings();
@@ -69,11 +68,9 @@ int main(int argc, char **argv)
 
     fprintf(stderr, "Verification Successful\n");
 
-    ret = 0;
-
+    ret = EXIT_SUCCESS;
  err:
-
-    if (ret) {
+    if (ret != EXIT_SUCCESS) {
         fprintf(stderr, "Error Verifying Data\n");
         ERR_print_errors_fp(stderr);
     }

demos/digest/BIO_f_md.c

@@ -36,15 +36,14 @@
 
 int main(int argc, char * argv[])
 {
-    int result = 1;
+    int ret = EXIT_FAILURE;
     OSSL_LIB_CTX *library_context = NULL;
     BIO *input = NULL;
-    BIO *bio_digest = NULL;
+    BIO *bio_digest = NULL, *reading = NULL;
     EVP_MD *md = NULL;
     unsigned char buffer[512];
-    size_t readct, writect;
     size_t digest_size;
-    char *digest_value=NULL;
+    char *digest_value = NULL;
     int j;
 
     input = BIO_new_fd( fileno(stdin), 1 );
@@ -89,9 +88,9 @@ int main(int argc, char * argv[])
      * We will use BIO chaining so that as we read, the digest gets updated
      * See the man page for BIO_push
      */
-    BIO *reading = BIO_push( bio_digest, input );
-    
-    while( BIO_read(reading, buffer, sizeof(buffer)) > 0 )
+    reading = BIO_push(bio_digest, input);
+
+    while (BIO_read(reading, buffer, sizeof(buffer)) > 0)
         ;
 
     /*-
@@ -106,10 +105,10 @@ int main(int argc, char * argv[])
         fprintf(stdout, "%02x", (unsigned char)digest_value[j]);
     }
     fprintf(stdout, "\n");
-    result = 0;
+    ret = EXIT_SUCCESS;
 
 cleanup:
-    if (result != 0) 
+    if (ret != EXIT_SUCCESS)
         ERR_print_errors_fp(stderr);
 
     OPENSSL_free(digest_value);
@@ -118,5 +117,5 @@ int main(int argc, char * argv[])
     EVP_MD_free(md);
     OSSL_LIB_CTX_free(library_context);
 
-    return result;
+    return ret;
 }

demos/digest/EVP_MD_demo.c

@@ -79,7 +79,7 @@ const unsigned char known_answer[] = {
 int demonstrate_digest(void)
 {
     OSSL_LIB_CTX *library_context;
-    int result = 0;
+    int ret = 0;
     const char *option_properties = NULL;
     EVP_MD *message_digest = NULL;
     EVP_MD_CTX *digest_context = NULL;
@@ -161,23 +161,22 @@ int demonstrate_digest(void)
         fprintf(stdout, "\nDigest does not match known answer\n");
     } else {
         fprintf(stdout, "Digest computed properly.\n");
-        result = 1;
+        ret = 1;
     }
 
-
 cleanup:
-    if (result != 1)
+    if (ret != 1)
         ERR_print_errors_fp(stderr);
     /* OpenSSL free functions will ignore NULL arguments */
     EVP_MD_CTX_free(digest_context);
     OPENSSL_free(digest_value);
     EVP_MD_free(message_digest);
 
     OSSL_LIB_CTX_free(library_context);
-    return result;
+    return ret;
 }
 
 int main(void)
 {
-    return demonstrate_digest() == 0;
+    return demonstrate_digest() ? EXIT_SUCCESS : EXIT_FAILURE;
 }