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>
(Merged from https://github.com/openssl/openssl/pull/20545)

4 files changed, 24 insertions, 24 deletions

diff --git a/demos/digest/BIO_f_md.c b/demos/digest/BIO_f_md.c
index 0a1f319f11..1317e82237 100644
--- a/demos/digest/BIO_f_md.c
+++ b/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);
@@ -89,7 +88,7 @@ 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);
+    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 @@ cleanup:
     EVP_MD_free(md);
     OSSL_LIB_CTX_free(library_context);
 
-    return result;
+    return ret;
 }
diff --git a/demos/digest/EVP_MD_demo.c b/demos/digest/EVP_MD_demo.c
index e406801aff..51a87559d2 100644
--- a/demos/digest/EVP_MD_demo.c
+++ b/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;
@@ -161,12 +161,11 @@ 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);
@@ -174,10 +173,10 @@ cleanup:
     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;
 }
diff --git a/demos/digest/EVP_MD_stdin.c b/demos/digest/EVP_MD_stdin.c
index 43a820f945..6990b721c5 100644
--- a/demos/digest/EVP_MD_stdin.c
+++ b/demos/digest/EVP_MD_stdin.c
@@ -34,7 +34,7 @@
 int demonstrate_digest(BIO *input)
 {
     OSSL_LIB_CTX *library_context = NULL;
-    int result = 0;
+    int ret = 0;
     const char * option_properties = NULL;
     EVP_MD *message_digest = NULL;
     EVP_MD_CTX *digest_context = NULL;
@@ -103,14 +103,14 @@ int demonstrate_digest(BIO *input)
         fprintf(stderr, "EVP_DigestFinal() failed.\n");
         goto cleanup;
     }
-    result = 1;
+    ret = 1;
     for (ii=0; ii<digest_length; ii++) {
         fprintf(stdout, "%02x", digest_value[ii]);
     }
     fprintf(stdout, "\n");
 
 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);
@@ -118,17 +118,19 @@ cleanup:
     EVP_MD_free(message_digest);
 
     OSSL_LIB_CTX_free(library_context);
-    return result;
+    return ret;
 }
 
 int main(void)
 {
-    int result = 1;
+    int ret = EXIT_FAILURE;
     BIO *input = BIO_new_fd(fileno(stdin), 1);
 
     if (input != NULL) {
-        result = demonstrate_digest(input);
+        ret = (demonstrate_digest(input) ? EXIT_SUCCESS : EXIT_FAILURE);
         BIO_free(input);
     }
-    return result;
+    if (ret != EXIT_SUCCESS)
+        ERR_print_errors_fp(stderr);
+    return ret;
 }
diff --git a/demos/digest/EVP_MD_xof.c b/demos/digest/EVP_MD_xof.c
index f31c047164..c2bd1a9fc5 100644
--- a/demos/digest/EVP_MD_xof.c
+++ b/demos/digest/EVP_MD_xof.c
@@ -43,7 +43,7 @@ static const char *propq = NULL;
 
 int main(int argc, char **argv)
 {
-    int rv = 1;
+    int ret = EXIT_FAILURE;
     OSSL_LIB_CTX *libctx = NULL;
     EVP_MD *md = NULL;
     EVP_MD_CTX *ctx = NULL;
@@ -122,11 +122,11 @@ int main(int argc, char **argv)
         }
     }
 
-    rv = 0;
+    ret = EXIT_SUCCESS;
 end:
     OPENSSL_free(digest);
     EVP_MD_CTX_free(ctx);
     EVP_MD_free(md);
     OSSL_LIB_CTX_free(libctx);
-    return rv;
+    return ret;
 }