Fix ret code in rsa_decrypt.c
diff --git a/programs/pkey/rsa_decrypt.c b/programs/pkey/rsa_decrypt.c
index 2da3fbf..0a252d2 100644
--- a/programs/pkey/rsa_decrypt.c
+++ b/programs/pkey/rsa_decrypt.c
@@ -30,11 +30,11 @@
 #else
 #include <stdio.h>
 #include <stdlib.h>
-#define mbedtls_printf     printf
-#define mbedtls_exit       exit
+#define mbedtls_printf       printf
+#define mbedtls_exit         exit
 #define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
 #define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
-#endif
+#endif /* MBEDTLS_PLATFORM_C */
 
 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_RSA_C) && \
     defined(MBEDTLS_FS_IO) && defined(MBEDTLS_ENTROPY_C) && \
@@ -61,7 +61,9 @@
 int main( int argc, char *argv[] )
 {
     FILE *f;
-    int return_val, exit_val, c;
+    int ret = 1;
+    int exit_code = MBEDTLS_EXIT_FAILURE;
+    int c;
     size_t i;
     mbedtls_rsa_context rsa;
     mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
@@ -73,7 +75,6 @@
     ((void) argv);
 
     memset(result, 0, sizeof( result ) );
-    exit_val = MBEDTLS_EXIT_SUCCESS;
 
     if( argc != 1 )
     {
@@ -83,7 +84,7 @@
         mbedtls_printf( "\n" );
 #endif
 
-        mbedtls_exit( MBEDTLS_EXIT_FAILURE );
+        mbedtls_exit( exit_code );
     }
 
     mbedtls_printf( "\n  . Seeding the random number generator..." );
@@ -96,14 +97,13 @@
     mbedtls_mpi_init( &D ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &DP );
     mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );
 
-    return_val = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
+    ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
                                         &entropy, (const unsigned char *) pers,
                                         strlen( pers ) );
-    if( return_val != 0 )
+    if( ret != 0 )
     {
-        exit_val = MBEDTLS_EXIT_FAILURE;
         mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned %d\n",
-                        return_val );
+                        ret );
         goto exit;
     }
 
@@ -112,40 +112,38 @@
 
     if( ( f = fopen( "rsa_priv.txt", "rb" ) ) == NULL )
     {
-        exit_val = MBEDTLS_EXIT_FAILURE;
         mbedtls_printf( " failed\n  ! Could not open rsa_priv.txt\n" \
                 "  ! Please run rsa_genkey first\n\n" );
         goto exit;
     }
 
-    if( ( return_val = mbedtls_mpi_read_file( &N , 16, f ) )  != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &E , 16, f ) )  != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &D , 16, f ) )  != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &P , 16, f ) )  != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &Q , 16, f ) )  != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &DP , 16, f ) ) != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &DQ , 16, f ) ) != 0 ||
-        ( return_val = mbedtls_mpi_read_file( &QP , 16, f ) ) != 0 )
+    if( ( ret = mbedtls_mpi_read_file( &N , 16, f ) )  != 0 ||
+        ( ret = mbedtls_mpi_read_file( &E , 16, f ) )  != 0 ||
+        ( ret = mbedtls_mpi_read_file( &D , 16, f ) )  != 0 ||
+        ( ret = mbedtls_mpi_read_file( &P , 16, f ) )  != 0 ||
+        ( ret = mbedtls_mpi_read_file( &Q , 16, f ) )  != 0 ||
+        ( ret = mbedtls_mpi_read_file( &DP , 16, f ) ) != 0 ||
+        ( ret = mbedtls_mpi_read_file( &DQ , 16, f ) ) != 0 ||
+        ( ret = mbedtls_mpi_read_file( &QP , 16, f ) ) != 0 )
     {
-        exit_val = MBEDTLS_EXIT_FAILURE;
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n",
-                        return_val );
+                        ret );
         fclose( f );
         goto exit;
     }
     fclose( f );
 
-    if( ( return_val = mbedtls_rsa_import( &rsa, &N, &P, &Q, &D, &E ) ) != 0 )
+    if( ( ret = mbedtls_rsa_import( &rsa, &N, &P, &Q, &D, &E ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_rsa_import returned %d\n\n",
-                        return_val );
+                        ret );
         goto exit;
     }
 
-    if( ( return_val = mbedtls_rsa_complete( &rsa ) ) != 0 )
+    if( ( ret = mbedtls_rsa_complete( &rsa ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_rsa_complete returned %d\n\n",
-                        return_val );
+                        ret );
         goto exit;
     }
 
@@ -154,7 +152,6 @@
      */
     if( ( f = fopen( "result-enc.txt", "rb" ) ) == NULL )
     {
-        exit_val = MBEDTLS_EXIT_FAILURE;
         mbedtls_printf( "\n  ! Could not open %s\n\n", "result-enc.txt" );
         goto exit;
     }
@@ -169,7 +166,6 @@
 
     if( i != rsa.len )
     {
-        exit_val = MBEDTLS_EXIT_FAILURE;
         mbedtls_printf( "\n  ! Invalid RSA signature format\n\n" );
         goto exit;
     }
@@ -180,14 +176,13 @@
     mbedtls_printf( "\n  . Decrypting the encrypted data" );
     fflush( stdout );
 
-    return_val = mbedtls_rsa_pkcs1_decrypt( &rsa, mbedtls_ctr_drbg_random,
+    ret = mbedtls_rsa_pkcs1_decrypt( &rsa, mbedtls_ctr_drbg_random,
                                             &ctr_drbg, MBEDTLS_RSA_PRIVATE, &i,
                                             buf, result, 1024 );
-    if( return_val != 0 )
+    if( ret != 0 )
     {
-        exit_val = MBEDTLS_EXIT_FAILURE;
         mbedtls_printf( " failed\n  ! mbedtls_rsa_pkcs1_decrypt returned %d\n\n",
-                        return_val );
+                        ret );
         goto exit;
     }
 
@@ -195,6 +190,8 @@
 
     mbedtls_printf( "The decrypted result is: '%s'\n\n", result );
 
+    exit_code = MBEDTLS_EXIT_SUCCESS;
+
 exit:
     mbedtls_ctr_drbg_free( &ctr_drbg );
     mbedtls_entropy_free( &entropy );
@@ -208,6 +205,6 @@
     fflush( stdout ); getchar();
 #endif
 
-    return( exit_val );
+    return( exit_code );
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_FS_IO */