Have the routines to get interface lists take a pointer to a "gchar *"

as an argument, and, on an error, if they have an error message, have
them set that "gchar *" to point to a g_malloc()ed string containing the
error message, rather than taking a pointer to a buffer for that message
as an argument.  That's more like what's done in Wiretap, and doesn't
impose an upper limit on the lengths of those error messages.  If that
pointer is null, don't allocate the message string and return it.

Have that error message already have the "cant_get" processing applied
to it, so nobody other than those routines need to call the "cant_get"
routines to process the error messages.

Have get_airpcap_interface_list() explicitly set "*err" to the
appropriate error code.

Clean up indentation.

svn path=/trunk/; revision=20521

1 files changed, 18 insertions, 24 deletions

diff --git a/capture_opts.c b/capture_opts.c
index 37db6321df..804b15deb5 100644
--- a/capture_opts.c
+++ b/capture_opts.c
@@ -238,8 +238,7 @@ capture_opts_add_iface_opt(capture_options *capture_opts, const char *optarg)
     GList       *if_list;
     if_info_t   *if_info;
     int         err;
-    gchar       err_str[CAPTURE_PCAP_ERRBUF_SIZE];
-    gchar       *cant_get_if_list_errstr;
+    gchar       *err_str;
 
 
     /*
@@ -262,18 +261,16 @@ capture_opts_add_iface_opt(capture_options *capture_opts, const char *optarg)
         return 1;
       }
       if (adapter_index == 0) {
-        cmdarg_err("there is no interface with that adapter index");
+        cmdarg_err("There is no interface with that adapter index");
         return 1;
       }
-      if_list = get_interface_list(&err, err_str);
+      if_list = get_interface_list(&err, &err_str);
       if (if_list == NULL) {
         switch (err) {
 
         case CANT_GET_INTERFACE_LIST:
-            cant_get_if_list_errstr =
-                cant_get_if_list_error_message(err_str);
-            cmdarg_err("%s", cant_get_if_list_errstr);
-            g_free(cant_get_if_list_errstr);
+            cmdarg_err("%s", err_str);
+            g_free(err_str);
             break;
 
         case NO_INTERFACES_FOUND:
@@ -284,7 +281,7 @@ capture_opts_add_iface_opt(capture_options *capture_opts, const char *optarg)
       }
       if_info = g_list_nth_data(if_list, adapter_index - 1);
       if (if_info == NULL) {
-        cmdarg_err("there is no interface with that adapter index");
+        cmdarg_err("There is no interface with that adapter index");
         return 1;
       }
       capture_opts->iface = g_strdup(if_info->name);
@@ -396,17 +393,18 @@ capture_opts_add_opt(capture_options *capture_opts, int opt, const char *optarg,
 
 int capture_opts_list_link_layer_types(capture_options *capture_opts)
 {
-    gchar err_str[CAPTURE_PCAP_ERRBUF_SIZE];
+    gchar *err_str;
     GList *lt_list, *lt_entry;
     data_link_info_t *data_link_info;
 
     /* Get the list of link-layer types for the capture device. */
-    lt_list = get_pcap_linktype_list(capture_opts->iface, err_str);
+    lt_list = get_pcap_linktype_list(capture_opts->iface, &err_str);
     if (lt_list == NULL) {
-      if (err_str[0] != '\0') {
+      if (err_str != NULL) {
         cmdarg_err("The list of data link types for the capture device \"%s\" could not be obtained (%s)."
          "Please check to make sure you have sufficient permissions, and that\n"
          "you have the proper interface or pipe specified.\n", capture_opts->iface, err_str);
+        g_free(err_str);
       } else
         cmdarg_err("The capture device \"%s\" has no data link types.", capture_opts->iface);
       return 2;
@@ -434,8 +432,7 @@ int capture_opts_list_interfaces()
     GList       *if_entry;
     if_info_t   *if_info;
     int         err;
-    gchar       err_str[CAPTURE_PCAP_ERRBUF_SIZE];
-    gchar       *cant_get_if_list_errstr;
+    gchar       *err_str;
     int         i;
 #if 0
     GSList      *ip_addr;
@@ -444,13 +441,12 @@ int capture_opts_list_interfaces()
 #endif
 
 
-    if_list = get_interface_list(&err, err_str);
+    if_list = get_interface_list(&err, &err_str);
     if (if_list == NULL) {
         switch (err) {
         case CANT_GET_INTERFACE_LIST:
-            cant_get_if_list_errstr = cant_get_if_list_error_message(err_str);
-            cmdarg_err("%s", cant_get_if_list_errstr);
-            g_free(cant_get_if_list_errstr);
+            cmdarg_err("%s", err_str);
+            g_free(err_str);
         break;
 
         case NO_INTERFACES_FOUND:
@@ -520,8 +516,7 @@ gboolean capture_opts_trim_iface(capture_options *capture_opts, const char *capt
     GList       *if_list;
     if_info_t   *if_info;
     int         err;
-    gchar       err_str[CAPTURE_PCAP_ERRBUF_SIZE];
-    gchar       *cant_get_if_list_errstr;
+    gchar       *err_str;
 
 
     /* Did the user specify an interface to use? */
@@ -532,14 +527,13 @@ gboolean capture_opts_trim_iface(capture_options *capture_opts, const char *capt
           capture_opts->iface = g_strdup(capture_device);
       } else {
         /* No - pick the first one from the list of interfaces. */
-        if_list = get_interface_list(&err, err_str);
+        if_list = get_interface_list(&err, &err_str);
         if (if_list == NULL) {
           switch (err) {
 
           case CANT_GET_INTERFACE_LIST:
-              cant_get_if_list_errstr = cant_get_if_list_error_message(err_str);
-              cmdarg_err("%s", cant_get_if_list_errstr);
-              g_free(cant_get_if_list_errstr);
+              cmdarg_err("%s", err_str);
+              g_free(err_str);
               break;
 
           case NO_INTERFACES_FOUND: