Introduce, and start using, tvb_get_const_stringz(). This function returns a

pointer to a NULL-terminated string in the TVB.  It is no safer than dissectors
which call tvb_get_strsize() and then tvb_get_ptr() but it makes it clear that
this usage of tvb_get_ptr() is safe.

This function is slightly more efficient than tvb_get_ephemeral_stringz()--but
only as long as we're not using composite TVBs.

svn path=/trunk/; revision=35493

1 files changed, 11 insertions, 5 deletions

diff --git a/doc/README.developer b/doc/README.developer
index 4109f166db..56e3424466 100644
--- a/doc/README.developer
+++ b/doc/README.developer
@@ -1277,20 +1277,26 @@ free() this buffer, it will happen automatically once the a new capture or
 file is opened.
 
 guint8 *tvb_get_stringz(tvbuff_t *tvb, gint offset, gint *lengthp);
+const guint8 *tvb_get_const stringz(tvbuff_t *tvb, gint offset, gint *lengthp);
 guint8 *tvb_get_ephemeral_stringz(tvbuff_t *tvb, gint offset, gint *lengthp);
 gchar  *tvb_get_ephemeral_unicode_stringz(tvbuff_t *tvb, const gint offset, gint *lengthp, const guint encoding);
 guint8 *tvb_get_seasonal_stringz(tvbuff_t *tvb, gint offset, gint *lengthp);
 
-Returns a null-terminated buffer, allocated with "g_malloc()",
-containing data from the specified tvbuff, starting at the
-specified offset, and containing all characters from the tvbuff up to
-and including a terminating null character in the tvbuff.  "*lengthp"
-will be set to the length of the string, including the terminating null.
+Returns a null-terminated buffer containing data from the specified tvbuff,
+starting at the specified offset, and containing all characters from the
+tvbuff up to and including a terminating null character in the tvbuff.
+"*lengthp" will be set to the length of the string, including the terminating
+null.
 
 tvb_get_stringz() returns a buffer allocated by g_malloc() so you must
 g_free() it when you are finished with the string. Failure to g_free() this
 buffer will lead to memory leaks.
 
+tvb_get_const_stringz() returns a pointer to the (const) string in the tvbuff.
+You do not need to free() this buffer, it will happen automatically once the
+next packet is dissected.  This function is slightly more efficient than the
+others because it does not allocate memory and copy the string.
+
 tvb_get_ephemeral_stringz() returns a buffer allocated from a special heap
 with a lifetime until the next packet is dissected. You do not need to
 free() this buffer, it will happen automatically once the next packet is