Unify the example programs' termination

This is done to account for platforms, for which we want custom behavior
upon the program termination, hence we call `mbedtls_exit()` instead of
returning from `main()`.

For the sake of consistency, introduces the modifications have been made
to the test and utility examples as well. These, while less likely to be
used in the low level environments, won't suffer from such a change.

programs/aes/aescrypt2.c

@@ -76,7 +76,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_AES_C and/or MBEDTLS_SHA256_C "
                     "and/or MBEDTLS_FS_IO and/or MBEDTLS_MD_C "
                     "not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -465,6 +465,6 @@ exit:
     mbedtls_aes_free( &aes_ctx );
     mbedtls_md_free( &sha_ctx );
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_AES_C && MBEDTLS_SHA256_C && MBEDTLS_FS_IO */

programs/aes/crypt_and_hash.c

@@ -78,7 +78,7 @@
 int main( void )
 {
     mbedtls_printf("MBEDTLS_CIPHER_C and/or MBEDTLS_MD_C and/or MBEDTLS_FS_IO not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -562,6 +562,6 @@ exit:
     mbedtls_cipher_free( &cipher_ctx );
     mbedtls_md_free( &md_ctx );
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_CIPHER_C && MBEDTLS_MD_C && MBEDTLS_FS_IO */

programs/hash/generic_sum.c

@@ -48,7 +48,7 @@
 int main( void )
 {
     mbedtls_printf("MBEDTLS_MD_C and/or MBEDTLS_FS_IO not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -203,7 +203,7 @@ int main( int argc, char *argv[] )
         fflush( stdout ); getchar();
 #endif
 
-        return( exit_code );
+        mbedtls_exit( exit_code );
     }
 
     /*
@@ -213,12 +213,12 @@ int main( int argc, char *argv[] )
     if( md_info == NULL )
     {
         mbedtls_fprintf( stderr, "Message Digest '%s' not found\n", argv[1] );
-        return( exit_code );
+        mbedtls_exit( exit_code );
     }
     if( mbedtls_md_setup( &md_ctx, md_info, 0 ) )
     {
         mbedtls_fprintf( stderr, "Failed to initialize context.\n" );
-        return( exit_code );
+        mbedtls_exit( exit_code );
     }
 
     ret = 0;
@@ -237,6 +237,6 @@ int main( int argc, char *argv[] )
 exit:
     mbedtls_md_free( &md_ctx );
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_MD_C && MBEDTLS_FS_IO */

programs/hash/hello.c

@@ -44,7 +44,7 @@
 int main( void )
 {
     mbedtls_printf("MBEDTLS_MD5_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -58,7 +58,7 @@ int main( void )
     mbedtls_printf( "\n  MD5('%s') = ", str );
 
     if( ( ret = mbedtls_md5_ret( (unsigned char *) str, 13, digest ) ) != 0 )
-        return( MBEDTLS_EXIT_FAILURE );
+        mbedtls_exit( MBEDTLS_EXIT_FAILURE );
 
     for( i = 0; i < 16; i++ )
         mbedtls_printf( "%02x", digest[i] );
@@ -70,6 +70,6 @@ int main( void )
     fflush( stdout ); getchar();
 #endif
 
-    return( MBEDTLS_EXIT_SUCCESS );
+    mbedtls_exit( MBEDTLS_EXIT_SUCCESS );
 }
 #endif /* MBEDTLS_MD5_C */

programs/pkey/dh_client.c

@@ -68,7 +68,7 @@ int main( void )
            "and/or MBEDTLS_NET_C and/or MBEDTLS_RSA_C and/or "
            "MBEDTLS_SHA256_C and/or MBEDTLS_FS_IO and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -307,7 +307,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_AES_C && MBEDTLS_DHM_C && MBEDTLS_ENTROPY_C &&
           MBEDTLS_NET_C && MBEDTLS_RSA_C && MBEDTLS_SHA256_C &&

programs/pkey/dh_genprime.c

@@ -45,7 +45,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
            "MBEDTLS_FS_IO and/or MBEDTLS_CTR_DRBG_C and/or "
            "MBEDTLS_GENPRIME not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -91,7 +91,7 @@ int main( int argc, char **argv )
     {
     usage:
         mbedtls_printf( USAGE );
-        return( exit_code );
+        mbedtls_exit( exit_code );
     }
 
     for( i = 1; i < argc; i++ )
@@ -197,7 +197,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_FS_IO &&
           MBEDTLS_CTR_DRBG_C && MBEDTLS_GENPRIME */

programs/pkey/dh_server.c

@@ -68,7 +68,7 @@ int main( void )
            "and/or MBEDTLS_NET_C and/or MBEDTLS_RSA_C and/or "
            "MBEDTLS_SHA256_C and/or MBEDTLS_FS_IO and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -330,7 +330,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_AES_C && MBEDTLS_DHM_C && MBEDTLS_ENTROPY_C &&
           MBEDTLS_NET_C && MBEDTLS_RSA_C && MBEDTLS_SHA256_C &&

programs/pkey/ecdh_curve25519.c

@@ -45,7 +45,7 @@ int main( void )
                     "MBEDTLS_ECP_DP_CURVE25519_ENABLED and/or "
                     "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C "
                     "not defined\n" );
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -238,7 +238,7 @@ exit:
     mbedtls_ctr_drbg_free( &ctr_drbg );
     mbedtls_entropy_free( &entropy );
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_ECDH_C && MBEDTLS_ECP_DP_CURVE25519_ENABLED &&
           MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */

programs/pkey/ecdsa.c

@@ -66,7 +66,7 @@ int main( void )
 {
     mbedtls_printf("MBEDTLS_ECDSA_C and/or MBEDTLS_SHA256_C and/or "
            "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C not defined\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 #if defined(VERBOSE)
@@ -248,7 +248,7 @@ exit:
     mbedtls_ctr_drbg_free( &ctr_drbg );
     mbedtls_entropy_free( &entropy );
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C &&
           ECPARAMS */

programs/pkey/gen_key.c

@@ -133,7 +133,7 @@ int main( void )
             "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C and/or "
             "MBEDTLS_PEM_WRITE_C"
             "not defined.\n" );
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -446,7 +446,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_PK_WRITE_C && MBEDTLS_PEM_WRITE_C && MBEDTLS_FS_IO &&
         * MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */

programs/pkey/key_app.c

@@ -70,7 +70,7 @@ int main( void )
 {
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or "
            "MBEDTLS_PK_PARSE_C and/or MBEDTLS_FS_IO not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -311,6 +311,6 @@ cleanup:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO */

programs/pkey/key_app_writer.c

@@ -94,7 +94,7 @@
 int main( void )
 {
     mbedtls_printf( "MBEDTLS_PK_PARSE_C and/or MBEDTLS_PK_WRITE_C and/or MBEDTLS_FS_IO not defined.\n" );
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -436,6 +436,6 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_PK_PARSE_C && MBEDTLS_PK_WRITE_C && MBEDTLS_FS_IO */

programs/pkey/mpi_demo.c

@@ -46,7 +46,7 @@
 int main( void )
 {
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_FS_IO not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -112,6 +112,6 @@ cleanup:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_FS_IO */

programs/pkey/pk_decrypt.c

@@ -56,7 +56,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_PK_PARSE_C and/or "
            "MBEDTLS_FS_IO and/or MBEDTLS_ENTROPY_C and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -171,7 +171,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO &&
           MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */

programs/pkey/pk_encrypt.c

@@ -57,7 +57,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_PK_PARSE_C and/or "
            "MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -176,7 +176,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_PK_PARSE_C && MBEDTLS_ENTROPY_C &&
           MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */

programs/pkey/pk_sign.c

@@ -47,7 +47,7 @@ int main( void )
            "MBEDTLS_SHA256_C and/or MBEDTLS_MD_C and/or "
            "MBEDTLS_PK_PARSE_C and/or MBEDTLS_FS_IO and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -174,7 +174,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C &&
           MBEDTLS_SHA256_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO &&

programs/pkey/pk_verify.c

@@ -45,7 +45,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_MD_C and/or "
            "MBEDTLS_SHA256_C and/or MBEDTLS_PK_PARSE_C and/or "
            "MBEDTLS_FS_IO not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -147,7 +147,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_SHA256_C &&
           MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO */

programs/pkey/rsa_decrypt.c

@@ -55,7 +55,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
            "MBEDTLS_FS_IO and/or MBEDTLS_ENTROPY_C and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -207,6 +207,6 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_FS_IO */

programs/pkey/rsa_encrypt.c

@@ -55,7 +55,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
            "MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO and/or "
            "MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -184,7 +184,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_ENTROPY_C &&
           MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */

programs/pkey/rsa_genkey.c

@@ -60,7 +60,7 @@ int main( void )
     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
            "MBEDTLS_RSA_C and/or MBEDTLS_GENPRIME and/or "
            "MBEDTLS_FS_IO and/or MBEDTLS_CTR_DRBG_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -186,7 +186,7 @@ exit:
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_code );
+    mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_RSA_C &&
           MBEDTLS_GENPRIME && MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */