Add tvb_ascii_isprint API

This allows dissectors to check if a portion of the tvb is an ascii string while hiding the use of tvb_get_ptr.

Change-Id: Iaec7559dcfdefb8a5ae23e099ced45e90e611f8f
Reviewed-on: https://code.wireshark.org/review/30291
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

4 files changed, 9 insertions, 47 deletions

diff --git a/epan/dissectors/asn1/dap/dap.cnf b/epan/dissectors/asn1/dap/dap.cnf
index c20d57af02..d4e7a98e75 100644
--- a/epan/dissectors/asn1/dap/dap.cnf
+++ b/epan/dissectors/asn1/dap/dap.cnf
@@ -290,13 +290,9 @@ OPERATION.&ResultType
 	%(DEFAULT_BODY)s
 
 	if(out_tvb) {
-		len = tvb_reported_length(out_tvb);
 		/* now see if we can add a string representation */
-		for(i=0; i<len; i++)
-			if(!g_ascii_isprint(tvb_get_guint8(out_tvb, i)))
-				break;
-
-		if(i == len) {
+		len = tvb_reported_length(out_tvb);
+		if(tvb_ascii_isprint(out_tvb, 0, len)) {
 			if(actx->created_item) {
 
 				proto_item_append_text(actx->created_item," (");
diff --git a/epan/dissectors/asn1/ldap/ldap.cnf b/epan/dissectors/asn1/ldap/ldap.cnf
index 624c311208..67a2d4a7ba 100644
--- a/epan/dissectors/asn1/ldap/ldap.cnf
+++ b/epan/dissectors/asn1/ldap/ldap.cnf
@@ -450,7 +450,6 @@ ldap_conv_info_t *ldap_info;
 
   tvbuff_t  *next_tvb = NULL;
   gchar *string;
-  guint32 i, len;
   int old_offset = offset;
   gint *hf_id;
 
@@ -470,13 +469,7 @@ ldap_conv_info_t *ldap_info;
     /* do the default thing */
   %(DEFAULT_BODY)s
 
-    len = tvb_reported_length_remaining(next_tvb, 0);
-
-    for(i = 0; i < len; i++)
-      if(!g_ascii_isprint(tvb_get_guint8(next_tvb, i)))
-        break;
-
-    if(i == len) {
+    if(tvb_ascii_isprint(next_tvb, 0, tvb_reported_length(next_tvb))) {
       string = tvb_get_string_enc(wmem_packet_scope(), next_tvb, 0, tvb_reported_length_remaining(next_tvb, 0), ENC_ASCII|ENC_NA);
       proto_item_set_text(actx->created_item, "AttributeValue: %%s", string);
     }
diff --git a/epan/dissectors/asn1/ldap/packet-ldap-template.c b/epan/dissectors/asn1/ldap/packet-ldap-template.c
index 7bdcb2bd96..01132effdb 100644
--- a/epan/dissectors/asn1/ldap/packet-ldap-template.c
+++ b/epan/dissectors/asn1/ldap/packet-ldap-template.c
@@ -633,8 +633,7 @@ dissect_ldap_AssertionValue(gboolean implicit_tag, tvbuff_t *tvb, int offset, as
   gint8 ber_class;
   gboolean pc, ind, is_ascii;
   gint32 tag;
-  guint32 len, i;
-  const guchar *str;
+  guint32 len;
 
   if(!implicit_tag){
     offset=get_ber_identifier(tvb, offset, &ber_class, &pc, &tag);
@@ -711,25 +710,13 @@ dissect_ldap_AssertionValue(gboolean implicit_tag, tvbuff_t *tvb, int offset, as
    * -- I don't think there are full schemas available that describe the
    *  interesting cases i.e. AD -- ronnie
    */
-  str=tvb_get_ptr(tvb, offset, len);
-  is_ascii=TRUE;
-  for(i=0;i<len;i++){
-    if(!g_ascii_isprint(str[i])){
-      is_ascii=FALSE;
-      break;
-    }
-  }
+  is_ascii=tvb_ascii_isprint(tvb, offset, len);
 
   /* convert the string into a printable string */
   if(is_ascii){
-    ldapvalue_string=wmem_strndup(wmem_packet_scope(), str, len);
+    ldapvalue_string= tvb_get_string_enc(wmem_packet_scope(), tvb, offset, len, ENC_ASCII);
   } else {
-    ldapvalue_string=(char*)wmem_alloc(wmem_packet_scope(), 3*len);
-    for(i=0;i<len;i++){
-      g_snprintf(ldapvalue_string+i*3,3,"%02x",str[i]&0xff);
-      ldapvalue_string[3*i+2]=':';
-    }
-    ldapvalue_string[3*len-1]=0;
+    ldapvalue_string= tvb_bytes_to_str_punct(wmem_packet_scope(), tvb, offset, len, ':');
   }
 
   proto_tree_add_string(tree, hf_index, tvb, offset, len, ldapvalue_string);
diff --git a/epan/dissectors/asn1/s1ap/s1ap.cnf b/epan/dissectors/asn1/s1ap/s1ap.cnf
index c22f71ba79..f0585435ad 100644
--- a/epan/dissectors/asn1/s1ap/s1ap.cnf
+++ b/epan/dissectors/asn1/s1ap/s1ap.cnf
@@ -243,7 +243,6 @@ MAX_VAL = asn1_param_get_integer(%(ACTX)s,"upperBound")
 #.FN_BODY ENBname VAL_PTR = parameter_tvb
   tvbuff_t *parameter_tvb=NULL;
   int length;
-  int p_offset;
   gboolean is_ascii;
 
 %(DEFAULT_BODY)s
@@ -253,20 +252,13 @@ MAX_VAL = asn1_param_get_integer(%(ACTX)s,"upperBound")
 
   length = tvb_reported_length(parameter_tvb);
 
-  is_ascii = TRUE;
-  for (p_offset=0; p_offset < length; p_offset++){
-    if(!g_ascii_isprint(tvb_get_guint8(parameter_tvb, p_offset ))){
-      is_ascii = FALSE;
-      break;
-    }
-  }
+  is_ascii = tvb_ascii_isprint(parameter_tvb, 0, length);
   if (is_ascii)
      proto_item_append_text(actx->created_item," (%%s)",tvb_format_text(parameter_tvb, 0, length));
 
 #.FN_BODY MMEname VAL_PTR = parameter_tvb
   tvbuff_t *parameter_tvb=NULL;
   int length;
-  int p_offset;
   gboolean is_ascii;
 
 %(DEFAULT_BODY)s
@@ -276,13 +268,7 @@ MAX_VAL = asn1_param_get_integer(%(ACTX)s,"upperBound")
 
   length = tvb_reported_length(parameter_tvb);
 
-  is_ascii = TRUE;
-  for (p_offset=0; p_offset < length; p_offset++){
-    if(!g_ascii_isprint(tvb_get_guint8(parameter_tvb, p_offset ))){
-      is_ascii = FALSE;
-      break;
-    }
-  }
+  is_ascii = tvb_ascii_isprint(parameter_tvb, 0, length);
   if (is_ascii)
      proto_item_append_text(actx->created_item," (%%s)",tvb_format_text(parameter_tvb, 0, length));