pkcs7: Correct various syntatical mistakes

Resond to feedback from the following comments:
 - use correct spacing [1-7]
 - remove unnecessary parenthesis [8]
 - fixup comments [9-11]
 - remove unnecessary init work [12]
 - use var instead of type for sizeof [13]
[1] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953655691
[2] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953661514
[3] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953689929
[4] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953696384
[5] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953697558
[6] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953697793
[7] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953697951
[8] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r953699102
[9] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r971223775
[10] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r967133905
[11] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r967135932
[12] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r967151430
[13] https://github.com/Mbed-TLS/mbedtls/pull/3431#discussion_r967154159
Signed-off-by: Nick Child <nick.child@ibm.com>
diff --git a/include/mbedtls/pkcs7.h b/include/mbedtls/pkcs7.h
index 7699b60..c56926f 100644
--- a/include/mbedtls/pkcs7.h
+++ b/include/mbedtls/pkcs7.h
@@ -22,23 +22,22 @@
  */
 
 /**
- * Note: For the time being, this application of the PKCS7 cryptographic
+ * Note: For the time being, this implementation of the PKCS7 cryptographic
  * message syntax is a partial implementation of RFC 2315.
  * Differences include:
  *  - The RFC specifies 6 different content types. The only type currently
- *    supported in MbedTLS is the signed data content type.
+ *    supported in Mbed TLS is the signed data content type.
  *  - The only supported PKCS7 Signed Data syntax version is version 1
- *  - The RFC specifies support for BER. This application is limited to
+ *  - The RFC specifies support for BER. This implementation is limited to
  *    DER only.
  *  - The RFC specifies that multiple digest algorithms can be specified
- *    in the Signed Data type. Only one digest algorithm is supported in MbedTLS.
- *  - The RFC specifies the Signed Data certificate format can be
- *    X509 or PKCS6. The only type currently supported in MbedTLS is X509.
+ *    in the Signed Data type. Only one digest algorithm is supported in Mbed TLS.
+ *  - The RFC specifies the Signed Data type can contain multiple X509 or PKCS6
+ *    certificates. In Mbed TLS, this list can only contain 0 or 1 certificates
+ *    and they must be in X509 format.
  *  - The RFC specifies the Signed Data type can contain
- *    certificate-revocation lists (crls). This application has no support
+ *    certificate-revocation lists (crls). This implementation has no support
  *    for crls so it is assumed to be an empty list.
- *  - The RFC specifies support for multiple signers. This application only
- *    supports the Signed Data type with a single signer.
  */
 
 #ifndef MBEDTLS_PKCS7_H
diff --git a/library/pkcs7.c b/library/pkcs7.c
index 9dcbab2..5ec1089 100644
--- a/library/pkcs7.c
+++ b/library/pkcs7.c
@@ -58,8 +58,7 @@
  */
 void mbedtls_pkcs7_init( mbedtls_pkcs7 *pkcs7 )
 {
-    memset( pkcs7, 0, sizeof( mbedtls_pkcs7 ) );
-    pkcs7->raw.p = NULL;
+    memset( pkcs7, 0, sizeof( *pkcs7 ) );
 }
 
 static int pkcs7_get_next_content_len( unsigned char **p, unsigned char *end,
@@ -229,7 +228,7 @@
      * So, we support only the root certificate and the single signer.
      * The behaviour would be improved with addition of multiple signer support.
      */
-    if (end_cert != end_set)
+    if ( end_cert != end_set )
     {
         ret = MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE;
         goto out;
@@ -702,7 +701,8 @@
 
 int mbedtls_pkcs7_signed_hash_verify( mbedtls_pkcs7 *pkcs7,
                                       const mbedtls_x509_crt *cert,
-                                      const unsigned char *hash, size_t hashlen)
+                                      const unsigned char *hash, 
+                                      size_t hashlen )
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     const mbedtls_md_info_t *md_info;
@@ -750,7 +750,7 @@
     }
 
 out:
-    return ( ret );
+    return( ret );
 }
 
 /*
diff --git a/tests/suites/test_suite_pkcs7.function b/tests/suites/test_suite_pkcs7.function
index 8db3f3f..c5094bc 100644
--- a/tests/suites/test_suite_pkcs7.function
+++ b/tests/suites/test_suite_pkcs7.function
@@ -76,15 +76,15 @@
 
     datalen = st.st_size;
     data = mbedtls_calloc( datalen, 1 );
-    TEST_ASSERT( data != NULL);
+    TEST_ASSERT( data != NULL );
 
     buflen = fread( (void *)data , sizeof( unsigned char ), datalen, file );
-    TEST_ASSERT( buflen == datalen);
+    TEST_ASSERT( buflen == datalen );
     fclose( file );
 
     if( do_hash_alg )
     {
-        res = mbedtls_oid_get_md_alg( &(pkcs7.signed_data.digest_alg_identifiers), &md_alg );
+        res = mbedtls_oid_get_md_alg( &pkcs7.signed_data.digest_alg_identifiers, &md_alg );
         TEST_ASSERT( res == 0 );
         TEST_ASSERT( md_alg == (mbedtls_md_type_t) do_hash_alg );
         md_info = mbedtls_md_info_from_type( md_alg );
@@ -162,7 +162,7 @@
 
     if( do_hash_alg )
     {
-        res = mbedtls_oid_get_md_alg( &(pkcs7.signed_data.digest_alg_identifiers), &md_alg );
+        res = mbedtls_oid_get_md_alg( &pkcs7.signed_data.digest_alg_identifiers, &md_alg );
         TEST_ASSERT( res == 0 );
         TEST_ASSERT( md_alg == MBEDTLS_MD_SHA256 );
 
@@ -171,7 +171,7 @@
         res = mbedtls_md( md_info, data, datalen, hash );
         TEST_ASSERT( res == 0 );
 
-        res = mbedtls_pkcs7_signed_hash_verify( &pkcs7, &x509_1, hash, sizeof(hash));
+        res = mbedtls_pkcs7_signed_hash_verify( &pkcs7, &x509_1, hash, sizeof(hash) );
         TEST_ASSERT( res == res_expect );
     }
     else