constification

5 files changed, 41 insertions, 52 deletions

diff --git a/src/src/acl.c b/src/src/acl.c
index cbf71ae1f..1ac2bee23 100644
--- a/src/src/acl.c
+++ b/src/src/acl.c
@@ -1283,7 +1283,6 @@ acl_verify_csa(const uschar *domain)
 {
 tree_node *t;
 const uschar *found;
-uschar *p;
 int priority, weight, port;
 dns_answer dnsa;
 dns_scan dnss;
@@ -1361,14 +1360,13 @@ switch (dns_special_lookup(&dnsa, domain, T_CSA, &found))
 /* Scan the reply for well-formed CSA SRV records. */
 
 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
-     rr != NULL;
-     rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
+     rr;
+     rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == T_SRV)
   {
-  if (rr->type != T_SRV) continue;
+  const uschar * p = rr->data;
 
   /* Extract the numerical SRV fields (p is incremented) */
 
-  p = rr->data;
   GETSHORT(priority, p);
   GETSHORT(weight, p);
   GETSHORT(port, p);
@@ -1387,12 +1385,7 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
   SRV records of their own. */
 
   if (Ustrcmp(found, domain) != 0)
-    {
-    if (port & 1)
-      return t->data.val = CSA_FAIL_EXPLICIT;
-    else
-      return t->data.val = CSA_UNKNOWN;
-    }
+    return t->data.val = port & 1 ? CSA_FAIL_EXPLICIT : CSA_UNKNOWN;
 
   /* This CSA SRV record refers directly to our domain, so we check the value
   in the weight field to work out the domain's authorization. 0 and 1 are
diff --git a/src/src/dns.c b/src/src/dns.c
index 575b81560..e02f494e8 100644
--- a/src/src/dns.c
+++ b/src/src/dns.c
@@ -309,7 +309,7 @@ else
 Return: TRUE for a bad result
 */
 static BOOL
-dnss_inc(dns_answer * dnsa, dns_scan * dnss, unsigned delta)
+dnss_inc_aptr(const dns_answer * dnsa, dns_scan * dnss, unsigned delta)
 {
 return (dnss->aptr += delta) >= dnsa->answer + dnsa->answerlen;
 }
@@ -332,9 +332,9 @@ Returns:    next dns record, or NULL when no more
 */
 
 dns_record *
-dns_next_rr(dns_answer *dnsa, dns_scan *dnss, int reset)
+dns_next_rr(const dns_answer *dnsa, dns_scan *dnss, int reset)
 {
-HEADER *h = (HEADER *)dnsa->answer;
+const HEADER * h = (const HEADER *)dnsa->answer;
 int namelen;
 
 char * trace = NULL;
@@ -363,7 +363,7 @@ if (reset != RESET_NEXT)
     if (namelen < 0) goto null_return;
     /* skip name & type & class */
     TRACE trace = "Q-skip";
-    if (dnss_inc(dnsa, dnss, namelen+4)) goto null_return;
+    if (dnss_inc_aptr(dnsa, dnss, namelen+4)) goto null_return;
     }
 
   /* Get the number of answer records. */
@@ -392,11 +392,11 @@ if (reset != RESET_NEXT)
       if (namelen < 0) goto null_return;
       /* skip name, type, class & TTL */
       TRACE trace = "A-hdr";
-      if (dnss_inc(dnsa, dnss, namelen+8)) goto null_return;
+      if (dnss_inc_aptr(dnsa, dnss, namelen+8)) goto null_return;
       GETSHORT(dnss->srr.size, dnss->aptr); /* size of data portion */
       /* skip over it */
       TRACE trace = "A-skip";
-      if (dnss_inc(dnsa, dnss, dnss->srr.size)) goto null_return;
+      if (dnss_inc_aptr(dnsa, dnss, dnss->srr.size)) goto null_return;
       }
     dnss->rrcount = reset == RESET_AUTHORITY
       ? ntohs(h->nscount) : ntohs(h->arcount);
@@ -423,11 +423,11 @@ if (namelen < 0) goto null_return;
 from the following bytes. */
 
 TRACE trace = "R-name";
-if (dnss_inc(dnsa, dnss, namelen)) goto null_return;
+if (dnss_inc_aptr(dnsa, dnss, namelen)) goto null_return;
 
 GETSHORT(dnss->srr.type, dnss->aptr);		/* Record type */
 TRACE trace = "R-class";
-if (dnss_inc(dnsa, dnss, 2)) goto null_return;	/* Don't want class */
+if (dnss_inc_aptr(dnsa, dnss, 2)) goto null_return;	/* Don't want class */
 GETLONG(dnss->srr.ttl, dnss->aptr);		/* TTL */
 GETSHORT(dnss->srr.size, dnss->aptr);		/* Size of data portion */
 dnss->srr.data = dnss->aptr;			/* The record's data follows */
@@ -466,12 +466,12 @@ dns_extract_auth_name(const dns_answer * dnsa)	/* FIXME: const dns_answer */
 {
 dns_scan dnss;
 dns_record * rr;
-HEADER * h = (HEADER *) dnsa->answer;
+const HEADER * h = (const HEADER *) dnsa->answer;
 
 if (!h->nscount || !h->aa) return NULL;
-for (rr = dns_next_rr((dns_answer*) dnsa, &dnss, RESET_AUTHORITY);
+for (rr = dns_next_rr(dnsa, &dnss, RESET_AUTHORITY);
      rr;
-     rr = dns_next_rr((dns_answer*) dnsa, &dnss, RESET_NEXT))
+     rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
   if (rr->type == (h->ancount ? T_NS : T_SOA)) return rr->name;
 return NULL;
 }
@@ -499,7 +499,7 @@ DEBUG(D_dns)
   debug_printf("DNSSEC support disabled at build-time; dns_is_secure() false\n");
 return FALSE;
 #else
-HEADER * h = (HEADER *) dnsa->answer;
+const HEADER * h = (const HEADER *) dnsa->answer;
 const uschar * auth_name;
 const uschar * trusted;
 
@@ -550,7 +550,7 @@ dns_is_aa(const dns_answer *dnsa)
 #ifdef DISABLE_DNSSEC
 return FALSE;
 #else
-return ((HEADER*)dnsa->answer)->aa;
+return ((const HEADER*)dnsa->answer)->aa;
 #endif
 }
 
@@ -874,7 +874,8 @@ for (i = 0; i < 10; i++)
 
   /* DNS lookup failures get passed straight back. */
 
-  if ((rc = dns_basic_lookup(dnsa, name, type)) != DNS_SUCCEED) return rc;
+  if ((rc = dns_basic_lookup(dnsa, name, type)) != DNS_SUCCEED)
+    return rc;
 
   /* We should have either records of the required type, or a CNAME record,
   or both. We need to know whether both exist for getting the fully qualified
@@ -886,22 +887,21 @@ for (i = 0; i < 10; i++)
   for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS);
        rr;
        rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
-    {
     if (rr->type == type)
       {
       if (type_rr.data == NULL) type_rr = *rr;
       if (cname_rr.data != NULL) break;
       }
-    else if (rr->type == T_CNAME) cname_rr = *rr;
-    }
+    else if (rr->type == T_CNAME)
+      cname_rr = *rr;
 
   /* For the first time round this loop, if a CNAME was found, take the fully
   qualified name from it; otherwise from the first data record, if present. */
 
-  if (i == 0 && fully_qualified_name != NULL)
+  if (i == 0 && fully_qualified_name)
     {
-    uschar * rr_name = cname_rr.data ? cname_rr.name
-      : type_rr.data ? type_rr.name : NULL;
+    uschar * rr_name = cname_rr.data
+      ? cname_rr.name : type_rr.data ? type_rr.name : NULL;
     if (  rr_name
        && Ustrcmp(rr_name, *fully_qualified_name) != 0
        && rr_name[0] != '*'
@@ -933,9 +933,8 @@ for (i = 0; i < 10; i++)
     return DNS_FAIL;
 
   data = store_get(256);
-  datalen = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen,
-    cname_rr.data, (DN_EXPAND_ARG4_TYPE)data, 256);
-  if (datalen < 0)
+  if ((datalen = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen,
+    cname_rr.data, (DN_EXPAND_ARG4_TYPE)data, 256)) < 0)
     return DNS_FAIL;
   name = data;
 
@@ -1083,7 +1082,7 @@ switch (type)
       success and packet length return values.) For added safety we only reset
       the packet length if the packet header looks plausible. */
 
-      HEADER *h = (HEADER *)dnsa->answer;
+      const HEADER * h = (const HEADER *)dnsa->answer;
       if (h->qr == 1 && h->opcode == QUERY && h->tc == 0
 	  && (h->rcode == NOERROR || h->rcode == NXDOMAIN)
 	  && ntohs(h->qdcount) == 1 && ntohs(h->ancount) == 0
@@ -1128,12 +1127,11 @@ switch (type)
 
       for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS);
 	   rr;
-	   rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
+	   rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == T_SRV)
 	{
-	if (rr->type != T_SRV) continue;
+	const uschar * p = rr->data;
 
 	/* Extract the numerical SRV fields (p is incremented) */
-	p = rr->data;
 	GETSHORT(priority, p);
 	GETSHORT(weight, p);	weight = weight; /* compiler quietening */
 	GETSHORT(port, p);
diff --git a/src/src/functions.h b/src/src/functions.h
index 05386d105..cc4e22b2e 100644
--- a/src/src/functions.h
+++ b/src/src/functions.h
@@ -158,7 +158,7 @@ extern BOOL    dns_is_secure(const dns_answer *);
 extern int     dns_lookup(dns_answer *, const uschar *, int, const uschar **);
 extern void    dns_pattern_init(void);
 extern int     dns_special_lookup(dns_answer *, const uschar *, int, const uschar **);
-extern dns_record *dns_next_rr(dns_answer *, dns_scan *, int);
+extern dns_record *dns_next_rr(const dns_answer *, dns_scan *, int);
 extern uschar *dns_text_type(int);
 extern void    dscp_list_to_stream(FILE *);
 extern BOOL    dscp_lookup(const uschar *, int, int *, int *, int *);
diff --git a/src/src/host.c b/src/src/host.c
index 7fda13d3c..25dab2bb8 100644
--- a/src/src/host.c
+++ b/src/src/host.c
@@ -2777,17 +2777,15 @@ host which is not the primary hostname. */
 last = NULL;    /* Indicates that not even the first item is filled yet */
 
 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
-     rr != NULL;
-     rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
+     rr;
+     rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == ind_type)
   {
   int precedence;
   int weight = 0;        /* For SRV records */
   int port = PORT_NONE;
-  uschar *s;             /* MUST be unsigned for GETSHORT */
+  const uschar * s = rr->data;	/* MUST be unsigned for GETSHORT */
   uschar data[256];
 
-  if (rr->type != ind_type) continue;
-  s = rr->data;
   GETSHORT(precedence, s);      /* Pointer s is advanced */
 
   /* For MX records, we use a random "weight" which causes multiple records of
diff --git a/src/src/structs.h b/src/src/structs.h
index 179ce58de..12d714f28 100644
--- a/src/src/structs.h
+++ b/src/src/structs.h
@@ -731,11 +731,11 @@ typedef struct search_cache {
 uncompressed, but the data pointer is into the raw data. */
 
 typedef struct {
-  uschar  name[DNS_MAXNAME];      /* domain name */
-  int     type;                   /* record type */
-  unsigned short ttl;		  /* time-to-live, seconds */
-  int     size;                   /* size of data */
-  uschar *data;                   /* pointer to data */
+  uschar        name[DNS_MAXNAME];      /* domain name */
+  int           type;                   /* record type */
+  unsigned short ttl;		        /* time-to-live, seconds */
+  int           size;                   /* size of data */
+  const uschar *data;                   /* pointer to data */
 } dns_record;
 
 /* Structure for holding the result of a DNS query. */
@@ -749,9 +749,9 @@ typedef struct {
 block. */
 
 typedef struct {
-  int     rrcount;                /* count of RRs in the answer */
-  uschar *aptr;                   /* pointer in the answer while scanning */
-  dns_record srr;                 /* data from current record in scan */
+  int            rrcount;         /* count of RRs in the answer */
+  const uschar *aptr;             /* pointer in the answer while scanning */
+  dns_record     srr;             /* data from current record in scan */
 } dns_scan;
 
 /* Structure for holding a chain of IP addresses that are extracted from