Clean up ftype-conversion and dfilter error message string handling.

Have dfilter_compile() take an additional gchar ** argument, pointing to
a gchar * item that, on error, gets set to point to a g_malloc()ed error
string.  That removes one bit of global state from the display filter
parser, and doesn't impose a fixed limit on the error message strings.

Have fvalue_from_string() and fvalue_from_unparsed() take a gchar **
argument, pointer to a gchar * item, rather than an error-reporting
function, and set the gchar * item to point to a g_malloc()ed error
string on an error.

Allow either gchar ** argument to be null; if the argument is null, no
error message is allocated or provided.

Change-Id: Ibd36b8aaa9bf4234aa6efa1e7fb95f7037493b4c
Reviewed-on: https://code.wireshark.org/review/6608
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 10 insertions, 6 deletions

diff --git a/epan/ftypes/ftype-double.c b/epan/ftypes/ftype-double.c
index ef1991815e..d4778b55ce 100644
--- a/epan/ftypes/ftype-double.c
+++ b/epan/ftypes/ftype-double.c
@@ -47,7 +47,7 @@ value_get_floating(fvalue_t *fv)
 }
 
 static gboolean
-val_from_unparsed(fvalue_t *fv, const char *s, gboolean allow_partial_value _U_, LogFunc logfunc)
+val_from_unparsed(fvalue_t *fv, const char *s, gboolean allow_partial_value _U_, gchar **err_msg)
 {
 	char    *endptr = NULL;
 
@@ -55,19 +55,23 @@ val_from_unparsed(fvalue_t *fv, const char *s, gboolean allow_partial_value _U_,
 
 	if (endptr == s || *endptr != '\0') {
 		/* This isn't a valid number. */
-		logfunc("\"%s\" is not a valid number.", s);
+		if (err_msg != NULL)
+			*err_msg = g_strdup_printf("\"%s\" is not a valid number.", s);
 		return FALSE;
 	}
 	if (errno == ERANGE) {
 		if (fv->value.floating == 0) {
-			logfunc("\"%s\" causes floating-point underflow.", s);
+			if (err_msg != NULL)
+				*err_msg = g_strdup_printf("\"%s\" causes floating-point underflow.", s);
 		}
 		else if (fv->value.floating == HUGE_VAL) {
-			logfunc("\"%s\" causes floating-point overflow.", s);
+			if (err_msg != NULL)
+				*err_msg = g_strdup_printf("\"%s\" causes floating-point overflow.", s);
 		}
 		else {
-			logfunc("\"%s\" is not a valid floating-point number.",
-			    s);
+			if (err_msg != NULL)
+				*err_msg = g_strdup_printf("\"%s\" is not a valid floating-point number.",
+				    s);
 		}
 		return FALSE;
 	}