diff --git a/library/x509write_crt.c b/library/x509write_crt.c
index 8e4bc35..0611cc8 100644
--- a/library/x509write_crt.c
+++ b/library/x509write_crt.c
@@ -51,7 +51,7 @@
 
 void mbedtls_x509write_crt_init( mbedtls_x509write_cert *ctx )
 {
-    memset( ctx, 0, sizeof(mbedtls_x509write_cert) );
+    memset( ctx, 0, sizeof( mbedtls_x509write_cert ) );
 
     mbedtls_mpi_init( &ctx->serial );
     ctx->version = MBEDTLS_X509_CRT_VERSION_3;
@@ -65,7 +65,7 @@
     mbedtls_asn1_free_named_data_list( &ctx->issuer );
     mbedtls_asn1_free_named_data_list( &ctx->extensions );
 
-    mbedtls_zeroize( ctx, sizeof(mbedtls_x509write_cert) );
+    mbedtls_zeroize( ctx, sizeof( mbedtls_x509write_cert ) );
 }
 
 void mbedtls_x509write_crt_set_version( mbedtls_x509write_cert *ctx, int version )
@@ -193,14 +193,14 @@
 {
     int ret;
     unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
-    unsigned char *c = buf + sizeof(buf);
+    unsigned char *c = buf + sizeof( buf );
     size_t len = 0;
 
     memset( buf, 0, sizeof(buf) );
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_pk_write_pubkey( &c, buf, ctx->issuer_key ) );
 
-    mbedtls_sha1( buf + sizeof(buf) - len, len, buf + sizeof(buf) - 20 );
-    c = buf + sizeof(buf) - 20;
+    mbedtls_sha1( buf + sizeof( buf ) - len, len, buf + sizeof( buf ) - 20 );
+    c = buf + sizeof( buf ) - 20;
     len = 20;
 
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
@@ -212,7 +212,7 @@
 
     return mbedtls_x509write_crt_set_extension( ctx, MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER,
                                    MBEDTLS_OID_SIZE( MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER ),
-                                   0, buf + sizeof(buf) - len, len );
+                                   0, buf + sizeof( buf ) - len, len );
 }
 #endif /* MBEDTLS_SHA1_C */
 
@@ -324,7 +324,7 @@
         pk_alg = MBEDTLS_PK_NONE;
 
     if( ( ret = mbedtls_oid_get_oid_by_sig_alg( pk_alg, ctx->md_alg,
-                                        &sig_oid, &sig_oid_len ) ) != 0 )
+                                          &sig_oid, &sig_oid_len ) ) != 0 )
     {
         return( ret );
     }
diff --git a/library/x509write_csr.c b/library/x509write_csr.c
index fd22c28..da40eb5 100644
--- a/library/x509write_csr.c
+++ b/library/x509write_csr.c
@@ -50,7 +50,7 @@
 
 void mbedtls_x509write_csr_init( mbedtls_x509write_csr *ctx )
 {
-    memset( ctx, 0, sizeof(mbedtls_x509write_csr) );
+    memset( ctx, 0, sizeof( mbedtls_x509write_csr ) );
 }
 
 void mbedtls_x509write_csr_free( mbedtls_x509write_csr *ctx )
@@ -58,7 +58,7 @@
     mbedtls_asn1_free_named_data_list( &ctx->subject );
     mbedtls_asn1_free_named_data_list( &ctx->extensions );
 
-    mbedtls_zeroize( ctx, sizeof(mbedtls_x509write_csr) );
+    mbedtls_zeroize( ctx, sizeof( mbedtls_x509write_csr ) );
 }
 
 void mbedtls_x509write_csr_set_md_alg( mbedtls_x509write_csr *ctx, mbedtls_md_type_t md_alg )
diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 45fd059..6504dcd 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.c
@@ -60,9 +60,9 @@
 
 #if defined(MBEDTLS_X509_CSR_PARSE_C)
 #define USAGE_CSR                                                           \
-    "    request_file=%%s     default: (empty)\n"                           \
-    "                        If request_file is specified, subject_key,\n"  \
-    "                        subject_pwd and subject_name are ignored!\n"
+    "    request_file=%%s         default: (empty)\n"                           \
+    "                            If request_file is specified, subject_key,\n"  \
+    "                            subject_pwd and subject_name are ignored!\n"
 #else
 #define USAGE_CSR ""
 #endif /* MBEDTLS_X509_CSR_PARSE_C */
@@ -94,60 +94,60 @@
     "\n usage: cert_write param=<>...\n"                \
     "\n acceptable parameters:\n"                       \
     USAGE_CSR                                           \
-    "    subject_key=%%s      default: subject.key\n"   \
-    "    subject_pwd=%%s      default: (empty)\n"       \
-    "    subject_name=%%s     default: CN=Cert,O=mbed TLS,C=UK\n"   \
+    "    subject_key=%%s          default: subject.key\n"   \
+    "    subject_pwd=%%s          default: (empty)\n"       \
+    "    subject_name=%%s         default: CN=Cert,O=mbed TLS,C=UK\n"   \
     "\n"                                                \
-    "    issuer_crt=%%s       default: (empty)\n"       \
-    "                        If issuer_crt is specified, issuer_name is\n"  \
-    "                        ignored!\n"                \
-    "    issuer_name=%%s      default: CN=CA,O=mbed TLS,C=UK\n"     \
+    "    issuer_crt=%%s           default: (empty)\n"       \
+    "                            If issuer_crt is specified, issuer_name is\n"  \
+    "                            ignored!\n"                \
+    "    issuer_name=%%s          default: CN=CA,O=mbed TLS,C=UK\n"     \
     "\n"                                                \
-    "    selfsign=%%d         default: 0 (false)\n"     \
-    "                        If selfsign is enabled, issuer_name and\n" \
-    "                        issuer_key are required (issuer_crt and\n" \
-    "                        subject_* are ignored\n"   \
-    "    issuer_key=%%s       default: ca.key\n"        \
-    "    issuer_pwd=%%s       default: (empty)\n"       \
-    "    output_file=%%s      default: cert.crt\n"      \
-    "    serial=%%s           default: 1\n"             \
-    "    not_before=%%s       default: 20010101000000\n"\
-    "    not_after=%%s        default: 20301231235959\n"\
-    "    is_ca=%%d            default: 0 (disabled)\n"  \
-    "    max_pathlen=%%d      default: -1 (none)\n"     \
-    "    md=%%s               default: SHA256\n"        \
-    "                        Supported values:\n"       \
-    "                        MD5, SHA1, SHA256, SHA512\n"\
-    "    version=%%d           default: 3\n"            \
-    "                        Possible values: 1, 2, 3\n"\
-    "    subject_identifier   default: 1\n"             \
-    "                        Possible values: 0, 1\n"   \
-    "                        (Considered for v3 only)\n"\
-    "    authority_identifier default: 1\n"             \
-    "                        Possible values: 0, 1\n"   \
-    "                        (Considered for v3 only)\n"\
-    "    basic_constraints    default: 1\n"             \
-    "                        Possible values: 0, 1\n"   \
-    "                        (Considered for v3 only)\n"\
-    "    key_usage=%%s        default: (empty)\n"       \
-    "                        Comma-separated-list of values:\n"     \
-    "                          digital_signature\n"     \
-    "                          non_repudiation\n"       \
-    "                          key_encipherment\n"      \
-    "                          data_encipherment\n"     \
-    "                          key_agreement\n"         \
-    "                          key_cert_sign\n"  \
-    "                          crl_sign\n"              \
-    "                        (Considered for v3 only)\n"\
-    "    ns_cert_type=%%s     default: (empty)\n"       \
-    "                        Comma-separated-list of values:\n"     \
-    "                          ssl_client\n"            \
-    "                          ssl_server\n"            \
-    "                          email\n"                 \
-    "                          object_signing\n"        \
-    "                          ssl_ca\n"                \
-    "                          email_ca\n"              \
-    "                          object_signing_ca\n"     \
+    "    selfsign=%%d             default: 0 (false)\n"     \
+    "                            If selfsign is enabled, issuer_name and\n" \
+    "                            issuer_key are required (issuer_crt and\n" \
+    "                            subject_* are ignored\n"   \
+    "    issuer_key=%%s           default: ca.key\n"        \
+    "    issuer_pwd=%%s           default: (empty)\n"       \
+    "    output_file=%%s          default: cert.crt\n"      \
+    "    serial=%%s               default: 1\n"             \
+    "    not_before=%%s           default: 20010101000000\n"\
+    "    not_after=%%s            default: 20301231235959\n"\
+    "    is_ca=%%d                default: 0 (disabled)\n"  \
+    "    max_pathlen=%%d          default: -1 (none)\n"     \
+    "    md=%%s                   default: SHA256\n"        \
+    "                            Supported values:\n"       \
+    "                            MD5, SHA1, SHA256, SHA512\n"\
+    "    version=%%d              default: 3\n"            \
+    "                            Possible values: 1, 2, 3\n"\
+    "    subject_identifier=%%s   default: 1\n"             \
+    "                            Possible values: 0, 1\n"   \
+    "                            (Considered for v3 only)\n"\
+    "    authority_identifier=%%s default: 1\n"             \
+    "                            Possible values: 0, 1\n"   \
+    "                            (Considered for v3 only)\n"\
+    "    basic_constraints=%%d    default: 1\n"             \
+    "                            Possible values: 0, 1\n"   \
+    "                            (Considered for v3 only)\n"\
+    "    key_usage=%%s            default: (empty)\n"       \
+    "                            Comma-separated-list of values:\n"     \
+    "                            digital_signature\n"     \
+    "                            non_repudiation\n"       \
+    "                            key_encipherment\n"      \
+    "                            data_encipherment\n"     \
+    "                            key_agreement\n"         \
+    "                            key_cert_sign\n"  \
+    "                            crl_sign\n"              \
+    "                            (Considered for v3 only)\n"\
+    "    ns_cert_type=%%s         default: (empty)\n"       \
+    "                            Comma-separated-list of values:\n"     \
+    "                            ssl_client\n"            \
+    "                            ssl_server\n"            \
+    "                            email\n"                 \
+    "                            object_signing\n"        \
+    "                            ssl_ca\n"                \
+    "                            email_ca\n"              \
+    "                            object_signing_ca\n"     \
     "\n"
 
 /*
@@ -189,7 +189,8 @@
     size_t len = 0;
 
     memset( output_buf, 0, 4096 );
-    if( ( ret = mbedtls_x509write_crt_pem( crt, output_buf, 4096, f_rng, p_rng ) ) < 0 )
+    if( ( ret = mbedtls_x509write_crt_pem( crt, output_buf, 4096,
+                                           f_rng, p_rng ) ) < 0 )
         return( ret );
 
     len = strlen( (char *) output_buf );
@@ -452,7 +453,8 @@
                                strlen( pers ) ) ) != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_ctr_drbg_seed returned %d - %s\n", ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_ctr_drbg_seed returned %d - %s\n",
+                        ret, buf );
         goto exit;
     }
 
@@ -466,7 +468,8 @@
     if( ( ret = mbedtls_mpi_read_string( &serial, 10, opt.serial ) ) != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_mpi_read_string returned -0x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_mpi_read_string "
+                        "returned -0x%02x - %s\n\n", -ret, buf );
         goto exit;
     }
 
@@ -485,7 +488,8 @@
         if( ( ret = mbedtls_x509_crt_parse_file( &issuer_crt, opt.issuer_crt ) ) != 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_parse_file returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_parse_file "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -494,7 +498,8 @@
         if( ret < 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_x509_dn_gets returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_x509_dn_gets "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -517,7 +522,8 @@
         if( ( ret = mbedtls_x509_csr_parse_file( &csr, opt.request_file ) ) != 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_x509_csr_parse_file returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_x509_csr_parse_file "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -526,7 +532,8 @@
         if( ret < 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_x509_dn_gets returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_x509_dn_gets "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -550,7 +557,8 @@
         if( ret != 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_pk_parse_keyfile returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_pk_parse_keyfile "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -565,7 +573,8 @@
     if( ret != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_pk_parse_keyfile returned -x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_pk_parse_keyfile "
+                        "returned -x%02x - %s\n\n", -ret, buf );
         goto exit;
     }
 
@@ -579,7 +588,8 @@
             mbedtls_mpi_cmp_mpi( &mbedtls_pk_rsa( issuer_crt.pk )->E,
                          &mbedtls_pk_rsa( *issuer_key )->E ) != 0 )
         {
-            mbedtls_printf( " failed\n  !  issuer_key does not match issuer certificate\n\n" );
+            mbedtls_printf( " failed\n  !  issuer_key does not match "
+                            "issuer certificate\n\n" );
             ret = -1;
             goto exit;
         }
@@ -602,14 +612,16 @@
     if( ( ret = mbedtls_x509write_crt_set_subject_name( &crt, opt.subject_name ) ) != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_subject_name returned -0x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_subject_name "
+                        "returned -0x%02x - %s\n\n", -ret, buf );
         goto exit;
     }
 
     if( ( ret = mbedtls_x509write_crt_set_issuer_name( &crt, opt.issuer_name ) ) != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_issuer_name returned -0x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_issuer_name "
+                        "returned -0x%02x - %s\n\n", -ret, buf );
         goto exit;
     }
 
@@ -623,7 +635,8 @@
     if( ret != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_serial returned -0x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_serial "
+                        "returned -0x%02x - %s\n\n", -ret, buf );
         goto exit;
     }
 
@@ -631,7 +644,8 @@
     if( ret != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_validity returned -0x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_validity "
+                        "returned -0x%02x - %s\n\n", -ret, buf );
         goto exit;
     }
 
@@ -702,7 +716,8 @@
         if( ret != 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_key_usage returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_key_usage "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -718,7 +733,8 @@
         if( ret != 0 )
         {
             mbedtls_strerror( ret, buf, 1024 );
-            mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_ns_cert_type returned -0x%02x - %s\n\n", -ret, buf );
+            mbedtls_printf( " failed\n  !  mbedtls_x509write_crt_set_ns_cert_type "
+                            "returned -0x%02x - %s\n\n", -ret, buf );
             goto exit;
         }
 
@@ -735,7 +751,8 @@
                                    mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
     {
         mbedtls_strerror( ret, buf, 1024 );
-        mbedtls_printf( " failed\n  !  write_certifcate -0x%02x - %s\n\n", -ret, buf );
+        mbedtls_printf( " failed\n  !  write_certificate -0x%02x - %s\n\n",
+                        -ret, buf );
         goto exit;
     }
 
diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index f906545..3bd2c35 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -114,7 +114,7 @@
 all_final += server1.v1.crt server1.v1.der
 
 # OpenSSL-generated certificates for comparison
-# Also provide certificates to DER format to allow
+# Also provide certificates in DER format to allow
 # direct binary comparison using e.g. dumpasn1
 server1.crt.openssl server1.key_usage.crt.openssl server1.cert_type.crt.openssl: server1.key server1.csr $(test_ca_crt) $(test_ca_key_file_rsa) $(test_ca_server1_config_file)
 	echo "01" > $(test_ca_server1_serial)
diff --git a/tests/suites/test_suite_x509write.function b/tests/suites/test_suite_x509write.function
index 0b6e602..ca76e86 100644
--- a/tests/suites/test_suite_x509write.function
+++ b/tests/suites/test_suite_x509write.function
@@ -63,7 +63,7 @@
     if( cert_type != 0 )
         TEST_ASSERT( mbedtls_x509write_csr_set_ns_cert_type( &req, cert_type ) == 0 );
 
-    ret = mbedtls_x509write_csr_pem( &req, buf, sizeof(buf),
+    ret = mbedtls_x509write_csr_pem( &req, buf, sizeof( buf ),
                              rnd_pseudo_rand, &rnd_info );
     TEST_ASSERT( ret == 0 );
 
@@ -149,7 +149,7 @@
 
     TEST_ASSERT( mbedtls_x509write_crt_set_serial( &crt, &serial ) == 0 );
     TEST_ASSERT( mbedtls_x509write_crt_set_validity( &crt, not_before,
-                                                   not_after ) == 0 );
+                                                     not_after ) == 0 );
     mbedtls_x509write_crt_set_md_alg( &crt, md_type );
     TEST_ASSERT( mbedtls_x509write_crt_set_issuer_name( &crt, issuer_name ) == 0 );
     TEST_ASSERT( mbedtls_x509write_crt_set_subject_name( &crt, subject_name ) == 0 );
@@ -169,30 +169,30 @@
             TEST_ASSERT( mbedtls_x509write_crt_set_ns_cert_type( &crt, cert_type ) == 0 );
     }
 
-    ret = mbedtls_x509write_crt_pem( &crt, buf, sizeof(buf),
-                             rnd_pseudo_rand, &rnd_info );
+    ret = mbedtls_x509write_crt_pem( &crt, buf, sizeof( buf ),
+                                     rnd_pseudo_rand, &rnd_info );
     TEST_ASSERT( ret == 0 );
 
     pem_len = strlen( (char *) buf );
 
     f = fopen( cert_check_file, "r" );
     TEST_ASSERT( f != NULL );
-    olen = fread( check_buf, 1, sizeof(check_buf), f );
+    olen = fread( check_buf, 1, sizeof( check_buf ), f );
     fclose( f );
-    TEST_ASSERT( olen < sizeof(check_buf) );
+    TEST_ASSERT( olen < sizeof( check_buf ) );
 
     TEST_ASSERT( olen >= pem_len - 1 );
     TEST_ASSERT( memcmp( buf, check_buf, pem_len - 1 ) == 0 );
 
     der_len = mbedtls_x509write_crt_der( &crt, buf, sizeof( buf ),
-                            rnd_pseudo_rand, &rnd_info );
+                                         rnd_pseudo_rand, &rnd_info );
     TEST_ASSERT( der_len >= 0 );
 
     if( der_len == 0 )
         goto exit;
 
     ret = mbedtls_x509write_crt_der( &crt, buf, (size_t)( der_len - 1 ),
-                            rnd_pseudo_rand, &rnd_info );
+                                     rnd_pseudo_rand, &rnd_info );
     TEST_ASSERT( ret == MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
 
 exit: