Explicitly test against NULL; do not use !p or similar

Also added blanks lines after declarations in a couple of places.

Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9916)

73 files changed, 278 insertions, 236 deletions

diff --git a/crypto/asn1/a_strnid.c b/crypto/asn1/a_strnid.c
index 630ac19259..ab54739714 100644
--- a/crypto/asn1/a_strnid.c
+++ b/crypto/asn1/a_strnid.c
@@ -51,7 +51,7 @@ int ASN1_STRING_set_default_mask_asc(const char *p)
     char *end;
 
     if (strncmp(p, "MASK:", 5) == 0) {
-        if (!p[5])
+        if (p[5] == '\0')
             return 0;
         mask = strtoul(p + 5, &end, 0);
         if (*end)
diff --git a/crypto/asn1/a_verify.c b/crypto/asn1/a_verify.c
index 9484bccf4c..92f9448749 100644
--- a/crypto/asn1/a_verify.c
+++ b/crypto/asn1/a_verify.c
@@ -116,7 +116,7 @@ int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a,
         goto err;
     }
     if (mdnid == NID_undef) {
-        if (!pkey->ameth || !pkey->ameth->item_verify) {
+        if (pkey->ameth == NULL || pkey->ameth->item_verify == NULL) {
             ASN1err(ASN1_F_ASN1_ITEM_VERIFY,
                     ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
             goto err;
diff --git a/crypto/asn1/ameth_lib.c b/crypto/asn1/ameth_lib.c
index 4295d889cb..9ea5b665ba 100644
--- a/crypto/asn1/ameth_lib.c
+++ b/crypto/asn1/ameth_lib.c
@@ -56,6 +56,7 @@ static const EVP_PKEY_ASN1_METHOD *pkey_asn1_find(int type)
 {
     EVP_PKEY_ASN1_METHOD tmp;
     const EVP_PKEY_ASN1_METHOD *t = &tmp, **ret;
+
     tmp.pkey_id = type;
     if (app_methods) {
         int idx;
@@ -64,7 +65,7 @@ static const EVP_PKEY_ASN1_METHOD *pkey_asn1_find(int type)
             return sk_EVP_PKEY_ASN1_METHOD_value(app_methods, idx);
     }
     ret = OBJ_bsearch_ameth(&t, standard_methods, OSSL_NELEM(standard_methods));
-    if (!ret || !*ret)
+    if (ret == NULL || *ret == NULL)
         return NULL;
     return *ret;
 }
diff --git a/crypto/asn1/asn_mime.c b/crypto/asn1/asn_mime.c
index 3282163199..757fe9eb7a 100644
--- a/crypto/asn1/asn_mime.c
+++ b/crypto/asn1/asn_mime.c
@@ -399,7 +399,7 @@ ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it)
     if (strcmp(hdr->value, "multipart/signed") == 0) {
         /* Split into two parts */
         prm = mime_param_find(hdr, "boundary");
-        if (!prm || !prm->param_value) {
+        if (prm == NULL || prm->param_value == NULL) {
             sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
             ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY);
             return NULL;
diff --git a/crypto/asn1/bio_ndef.c b/crypto/asn1/bio_ndef.c
index db9bbba940..bc7b4499d0 100644
--- a/crypto/asn1/bio_ndef.c
+++ b/crypto/asn1/bio_ndef.c
@@ -108,7 +108,7 @@ static int ndef_prefix(BIO *b, unsigned char **pbuf, int *plen, void *parg)
     unsigned char *p;
     int derlen;
 
-    if (!parg)
+    if (parg == NULL)
         return 0;
 
     ndef_aux = *(NDEF_SUPPORT **)parg;
@@ -123,7 +123,7 @@ static int ndef_prefix(BIO *b, unsigned char **pbuf, int *plen, void *parg)
     *pbuf = p;
     derlen = ASN1_item_ndef_i2d(ndef_aux->val, &p, ndef_aux->it);
 
-    if (!*ndef_aux->boundary)
+    if (*ndef_aux->boundary == NULL)
         return 0;
 
     *plen = *ndef_aux->boundary - *pbuf;
@@ -136,7 +136,7 @@ static int ndef_prefix_free(BIO *b, unsigned char **pbuf, int *plen,
 {
     NDEF_SUPPORT *ndef_aux;
 
-    if (!parg)
+    if (parg == NULL)
         return 0;
 
     ndef_aux = *(NDEF_SUPPORT **)parg;
@@ -168,7 +168,7 @@ static int ndef_suffix(BIO *b, unsigned char **pbuf, int *plen, void *parg)
     const ASN1_AUX *aux;
     ASN1_STREAM_ARG sarg;
 
-    if (!parg)
+    if (parg == NULL)
         return 0;
 
     ndef_aux = *(NDEF_SUPPORT **)parg;
@@ -195,7 +195,7 @@ static int ndef_suffix(BIO *b, unsigned char **pbuf, int *plen, void *parg)
     *pbuf = p;
     derlen = ASN1_item_ndef_i2d(ndef_aux->val, &p, ndef_aux->it);
 
-    if (!*ndef_aux->boundary)
+    if (*ndef_aux->boundary == NULL)
         return 0;
     *pbuf = *ndef_aux->boundary;
     *plen = derlen - (*ndef_aux->boundary - ndef_aux->derbuf);
diff --git a/crypto/asn1/d2i_pr.c b/crypto/asn1/d2i_pr.c
index b24f99118e..08101a826b 100644
--- a/crypto/asn1/d2i_pr.c
+++ b/crypto/asn1/d2i_pr.c
@@ -48,7 +48,7 @@ EVP_PKEY *d2i_PrivateKey(int type, EVP_PKEY **a, const unsigned char **pp,
             EVP_PKEY *tmp;
             PKCS8_PRIV_KEY_INFO *p8 = NULL;
             p8 = d2i_PKCS8_PRIV_KEY_INFO(NULL, &p, length);
-            if (!p8)
+            if (p8 == NULL)
                 goto err;
             tmp = EVP_PKCS82PKEY(p8);
             PKCS8_PRIV_KEY_INFO_free(p8);
@@ -104,7 +104,7 @@ EVP_PKEY *d2i_AutoPrivateKey(EVP_PKEY **a, const unsigned char **pp,
         EVP_PKEY *ret;
 
         sk_ASN1_TYPE_pop_free(inkey, ASN1_TYPE_free);
-        if (!p8) {
+        if (p8 == NULL) {
             ASN1err(ASN1_F_D2I_AUTOPRIVATEKEY,
                     ASN1_R_UNSUPPORTED_PUBLIC_KEY_TYPE);
             return NULL;
diff --git a/crypto/asn1/p5_pbev2.c b/crypto/asn1/p5_pbev2.c
index 49298f353f..f7f5f4655a 100644
--- a/crypto/asn1/p5_pbev2.c
+++ b/crypto/asn1/p5_pbev2.c
@@ -107,7 +107,7 @@ X509_ALGOR *PKCS5_pbe2_set_iv(const EVP_CIPHER *cipher, int iter,
 
     pbe2->keyfunc = PKCS5_pbkdf2_set(iter, salt, saltlen, prf_nid, keylen);
 
-    if (!pbe2->keyfunc)
+    if (pbe2->keyfunc == NULL)
         goto merr;
 
     /* Now set up top level AlgorithmIdentifier */
diff --git a/crypto/asn1/t_spki.c b/crypto/asn1/t_spki.c
index 5cbb13e33d..b634808c43 100644
--- a/crypto/asn1/t_spki.c
+++ b/crypto/asn1/t_spki.c
@@ -30,7 +30,7 @@ int NETSCAPE_SPKI_print(BIO *out, NETSCAPE_SPKI *spki)
     BIO_printf(out, "  Public Key Algorithm: %s\n",
                (i == NID_undef) ? "UNKNOWN" : OBJ_nid2ln(i));
     pkey = X509_PUBKEY_get(spki->spkac->pubkey);
-    if (!pkey)
+    if (pkey == NULL)
         BIO_printf(out, "  Unable to load public key\n");
     else {
         EVP_PKEY_print_public(out, pkey, 4, NULL);
diff --git a/crypto/asn1/tasn_dec.c b/crypto/asn1/tasn_dec.c
index e7c49526fc..f720c6020a 100644
--- a/crypto/asn1/tasn_dec.c
+++ b/crypto/asn1/tasn_dec.c
@@ -108,7 +108,8 @@ ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
 {
     ASN1_TLC c;
     ASN1_VALUE *ptmpval = NULL;
-    if (!pval)
+
+    if (pval == NULL)
         pval = &ptmpval;
     asn1_tlc_clear_nc(&c);
     if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
@@ -149,7 +150,8 @@ static int asn1_item_embed_d2i(ASN1_VALUE **pval, const unsigned char **in,
     int otag;
     int ret = 0;
     ASN1_VALUE **pchptr;
-    if (!pval)
+
+    if (pval == NULL)
         return 0;
     if (aux && aux->asn1_cb)
         asn1_cb = aux->asn1_cb;
@@ -303,7 +305,7 @@ static int asn1_item_embed_d2i(ASN1_VALUE **pval, const unsigned char **in,
             goto err;
         }
 
-        if (!*pval && !ASN1_item_ex_new(pval, it)) {
+        if (*pval == NULL && !ASN1_item_ex_new(pval, it)) {
             ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ERR_R_NESTED_ASN1_ERROR);
             goto err;
         }
@@ -554,7 +556,7 @@ static int asn1_template_noexp_d2i(ASN1_VALUE **val,
             return 0;
         } else if (ret == -1)
             return -1;
-        if (!*val)
+        if (*val == NULL)
             *val = (ASN1_VALUE *)sk_ASN1_VALUE_new_null();
         else {
             /*
@@ -568,7 +570,7 @@ static int asn1_template_noexp_d2i(ASN1_VALUE **val,
             }
         }
 
-        if (!*val) {
+        if (*val == NULL) {
             ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE);
             goto err;
         }
@@ -649,7 +651,8 @@ static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
     BUF_MEM buf = { 0, NULL, 0, 0 };
     const unsigned char *cont = NULL;
     long len;
-    if (!pval) {
+
+    if (pval == NULL) {
         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
         return 0;               /* Should never happen */
     }
@@ -786,7 +789,7 @@ static int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
         return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
     /* If ANY type clear type and set pointer to internal value */
     if (it->utype == V_ASN1_ANY) {
-        if (!*pval) {
+        if (*pval == NULL) {
             typ = ASN1_TYPE_new();
             if (typ == NULL)
                 goto err;
@@ -866,7 +869,7 @@ static int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
             goto err;
         }
         /* All based on ASN1_STRING and handled the same */
-        if (!*pval) {
+        if (*pval == NULL) {
             stmp = ASN1_STRING_type_new(utype);
             if (stmp == NULL) {
                 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE);
@@ -1058,10 +1061,11 @@ static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
 static int asn1_check_eoc(const unsigned char **in, long len)
 {
     const unsigned char *p;
+
     if (len < 2)
         return 0;
     p = *in;
-    if (!p[0] && !p[1]) {
+    if (p[0] == '\0' && p[1] == '\0') {
         *in += 2;
         return 1;
     }
diff --git a/crypto/asn1/tasn_enc.c b/crypto/asn1/tasn_enc.c
index a499665a2f..d8abd81698 100644
--- a/crypto/asn1/tasn_enc.c
+++ b/crypto/asn1/tasn_enc.c
@@ -55,7 +55,7 @@ int ASN1_item_i2d(const ASN1_VALUE *val, unsigned char **out, const ASN1_ITEM *i
 static int asn1_item_flags_i2d(const ASN1_VALUE *val, unsigned char **out,
                                const ASN1_ITEM *it, int flags)
 {
-    if (out && !*out) {
+    if (out != NULL && *out == NULL) {
         unsigned char *p, *buf;
         int len;
 
@@ -89,7 +89,7 @@ int ASN1_item_ex_i2d(const ASN1_VALUE **pval, unsigned char **out,
     const ASN1_AUX *aux = it->funcs;
     ASN1_aux_const_cb *asn1_cb = NULL;
 
-    if ((it->itype != ASN1_ITYPE_PRIMITIVE) && !*pval)
+    if ((it->itype != ASN1_ITYPE_PRIMITIVE) && *pval == NULL)
         return 0;
 
     if (aux != NULL) {
@@ -258,7 +258,7 @@ static int asn1_template_ex_i2d(const ASN1_VALUE **pval, unsigned char **out,
         int skcontlen, sklen;
         const ASN1_VALUE *skitem;
 
-        if (!*pval)
+        if (*pval == NULL)
             return 0;
 
         if (flags & ASN1_TFLG_SET_OF) {
@@ -510,7 +510,7 @@ static int asn1_ex_i2c(const ASN1_VALUE **pval, unsigned char *cout, int *putype
     /* Should type be omitted? */
     if ((it->itype != ASN1_ITYPE_PRIMITIVE)
         || (it->utype != V_ASN1_BOOLEAN)) {
-        if (!*pval)
+        if (*pval == NULL)
             return -1;
     }
 
diff --git a/crypto/asn1/tasn_fre.c b/crypto/asn1/tasn_fre.c
index 5749e2c770..e8d57bdaad 100644
--- a/crypto/asn1/tasn_fre.c
+++ b/crypto/asn1/tasn_fre.c
@@ -33,9 +33,9 @@ void asn1_item_embed_free(ASN1_VALUE **pval, const ASN1_ITEM *it, int embed)
     ASN1_aux_cb *asn1_cb;
     int i;
 
-    if (!pval)
+    if (pval == NULL)
         return;
-    if ((it->itype != ASN1_ITYPE_PRIMITIVE) && !*pval)
+    if ((it->itype != ASN1_ITYPE_PRIMITIVE) && *pval == NULL)
         return;
     if (aux && aux->asn1_cb)
         asn1_cb = aux->asn1_cb;
@@ -168,15 +168,15 @@ void asn1_primitive_free(ASN1_VALUE **pval, const ASN1_ITEM *it, int embed)
 
         utype = typ->type;
         pval = &typ->value.asn1_value;
-        if (!*pval)
+        if (*pval == NULL)
             return;
     } else if (it->itype == ASN1_ITYPE_MSTRING) {
         utype = -1;
-        if (!*pval)
+        if (*pval == NULL)
             return;
     } else {
         utype = it->utype;
-        if ((utype != V_ASN1_BOOLEAN) && !*pval)
+        if ((utype != V_ASN1_BOOLEAN) && *pval == NULL)
             return;
     }
 
diff --git a/crypto/asn1/x_bignum.c b/crypto/asn1/x_bignum.c
index c5e892900e..3ae58a49f0 100644
--- a/crypto/asn1/x_bignum.c
+++ b/crypto/asn1/x_bignum.c
@@ -82,7 +82,7 @@ static int bn_secure_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
 
 static void bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
 {
-    if (!*pval)
+    if (*pval == NULL)
         return;
     if (it->size & BN_SENSITIVE)
         BN_clear_free((BIGNUM *)*pval);
@@ -96,7 +96,7 @@ static int bn_i2c(const ASN1_VALUE **pval, unsigned char *cont, int *putype,
 {
     BIGNUM *bn;
     int pad;
-    if (!*pval)
+    if (*pval == NULL)
         return -1;
     bn = (BIGNUM *)*pval;
     /* If MSB set in an octet we need a padding byte */
@@ -133,7 +133,7 @@ static int bn_secure_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
     int ret;
     BIGNUM *bn;
 
-    if (!*pval && !bn_secure_new(pval, it))
+    if (*pval == NULL && !bn_secure_new(pval, it))
         return 0;
 
     ret = bn_c2i(pval, cont, len, utype, free_cont, it);
diff --git a/crypto/async/async.c b/crypto/async/async.c
index 4743bb702b..312f47325b 100644
--- a/crypto/async/async.c
+++ b/crypto/async/async.c
@@ -287,7 +287,7 @@ static void async_empty_pool(async_pool *pool)
 {
     ASYNC_JOB *job;
 
-    if (!pool || !pool->jobs)
+    if (pool == NULL || pool->jobs == NULL)
         return;
 
     do {
diff --git a/crypto/bn/bn_gf2m.c b/crypto/bn/bn_gf2m.c
index bfece40c59..7a56745fe2 100644
--- a/crypto/bn/bn_gf2m.c
+++ b/crypto/bn/bn_gf2m.c
@@ -297,7 +297,7 @@ int BN_GF2m_mod_arr(BIGNUM *r, const BIGNUM *a, const int p[])
 
     bn_check_top(a);
 
-    if (!p[0]) {
+    if (p[0] == 0) {
         /* reduction mod 1 => return 0 */
         BN_zero(r);
         return 1;
@@ -929,7 +929,7 @@ int BN_GF2m_mod_sqrt_arr(BIGNUM *r, const BIGNUM *a, const int p[],
 
     bn_check_top(a);
 
-    if (!p[0]) {
+    if (p[0] == 0) {
         /* reduction mod 1 => return 0 */
         BN_zero(r);
         return 1;
@@ -988,7 +988,7 @@ int BN_GF2m_mod_solve_quad_arr(BIGNUM *r, const BIGNUM *a_, const int p[],
 
     bn_check_top(a_);
 
-    if (!p[0]) {
+    if (p[0] == 0) {
         /* reduction mod 1 => return 0 */
         BN_zero(r);
         return 1;
diff --git a/crypto/cms/cms_env.c b/crypto/cms/cms_env.c
index bcb6162b18..ecece987ae 100644
--- a/crypto/cms/cms_env.c
+++ b/crypto/cms/cms_env.c
@@ -56,14 +56,15 @@ int cms_env_asn1_ctrl(CMS_RecipientInfo *ri, int cmd)
         pkey = ri->d.ktri->pkey;
     else if (ri->type == CMS_RECIPINFO_AGREE) {
         EVP_PKEY_CTX *pctx = ri->d.kari->pctx;
-        if (!pctx)
+
+        if (pctx == NULL)
             return 0;
         pkey = EVP_PKEY_CTX_get0_pkey(pctx);
-        if (!pkey)
+        if (pkey == NULL)
             return 0;
     } else
         return 0;
-    if (!pkey->ameth || !pkey->ameth->pkey_ctrl)
+    if (pkey->ameth == NULL || pkey->ameth->pkey_ctrl == NULL)
         return 1;
     i = pkey->ameth->pkey_ctrl(pkey, ASN1_PKEY_CTRL_CMS_ENVELOPE, cmd, ri);
     if (i == -2) {
@@ -191,7 +192,7 @@ CMS_RecipientInfo *CMS_add1_recipient_cert(CMS_ContentInfo *cms,
         goto merr;
 
     pk = X509_get0_pubkey(recip);
-    if (!pk) {
+    if (pk == NULL) {
         CMSerr(CMS_F_CMS_ADD1_RECIPIENT_CERT, CMS_R_ERROR_GETTING_PUBLIC_KEY);
         goto err;
     }
diff --git a/crypto/cms/cms_ess.c b/crypto/cms/cms_ess.c
index 1a6c05f1af..00a08aafea 100644
--- a/crypto/cms/cms_ess.c
+++ b/crypto/cms/cms_ess.c
@@ -202,7 +202,7 @@ int cms_Receipt_verify(CMS_ContentInfo *cms, CMS_ContentInfo *req_cms)
 
     /* Extract and decode receipt content */
     pcont = CMS_get0_content(cms);
-    if (!pcont || !*pcont) {
+    if (pcont == NULL || *pcont == NULL) {
         CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NO_CONTENT);
         goto err;
     }
diff --git a/crypto/cms/cms_kari.c b/crypto/cms/cms_kari.c
index 3820d0e229..6b0a59ebde 100644
--- a/crypto/cms/cms_kari.c
+++ b/crypto/cms/cms_kari.c
@@ -159,10 +159,10 @@ int CMS_RecipientInfo_kari_set0_pkey(CMS_RecipientInfo *ri, EVP_PKEY *pk)
 
     EVP_PKEY_CTX_free(kari->pctx);
     kari->pctx = NULL;
-    if (!pk)
+    if (pk == NULL)
         return 1;
     pctx = EVP_PKEY_CTX_new(pk, NULL);
-    if (!pctx || EVP_PKEY_derive_init(pctx) <= 0)
+    if (pctx == NULL || EVP_PKEY