device tree: fix crash when device tree is not found

* check if device tree was found before add_keys()
* UNKIFNULL(model) before strcmp
* make UNKIFNULL() STRIFNULL() EMPIFNULL() macros more generic

Signed-off-by: Burt P <pburt0@gmail.com>

2 files changed, 25 insertions, 13 deletions

diff --git a/modules/devices/devicetree/dt_util.c b/modules/devices/devicetree/dt_util.c
index 6ef41bd6..619e63be 100644
--- a/modules/devices/devicetree/dt_util.c
+++ b/modules/devices/devicetree/dt_util.c
@@ -221,19 +221,24 @@ const char *dtr_find_device_tree_root() {
             return candidates[i];
         i++;
     }
-    return "/did/not/find/device-tree";
+    return NULL;
 }
 
 dtr *dtr_new_x(char *base_path, int fast) {
     dtr *dt = malloc(sizeof(dtr));
     if (dt != NULL) {
         memset(dt, 0, sizeof(dtr));
+        dt->log = strdup("");
+
+        if (base_path == NULL)
+            base_path = DTR_ROOT;
+
         if (base_path != NULL)
             dt->base_path = strdup(base_path);
-        else
-            dt->base_path = strdup(DTR_ROOT);
-
-        dt->log = strdup("");
+        else {
+            dtr_msg(dt, "%s", "Device Tree not found.");
+            return dt;
+        }
 
         /* build alias and phandle lists */
         dt->aliases = NULL;
@@ -263,6 +268,14 @@ void dtr_free(dtr *s) {
     }
 }
 
+int dtr_was_found(dtr *s) {
+    if (s != NULL) {
+        if (s->base_path != NULL)
+            return 1;
+    }
+    return 0;
+}
+
 void dtr_msg(dtr *s, char *fmt, ...) {
     gchar *buf, *tmp;
     va_list args;
diff --git a/modules/devices/devicetree/pmac_data.c b/modules/devices/devicetree/pmac_data.c
index 01b08419..b236aef1 100644
--- a/modules/devices/devicetree/pmac_data.c
+++ b/modules/devices/devicetree/pmac_data.c
@@ -58,14 +58,13 @@ static gchar *ppc_mac_details(void) {
     if (machine == NULL)
         goto pmd_exit;
 
-#define _UNKIFNULL(STR) if (STR == NULL) { STR = strdup(_("(Unknown)")); }
-    _UNKIFNULL(platform);
-    _UNKIFNULL(model);
-    _UNKIFNULL(motherboard);
-    _UNKIFNULL(detected_as);
-    _UNKIFNULL(pmac_flags);
-    _UNKIFNULL(l2_cache);
-    _UNKIFNULL(pmac_gen);
+    UNKIFNULL(platform);
+    UNKIFNULL(model);
+    UNKIFNULL(motherboard);
+    UNKIFNULL(detected_as);
+    UNKIFNULL(pmac_flags);
+    UNKIFNULL(l2_cache);
+    UNKIFNULL(pmac_gen);
 
     ret = g_strdup_printf("[%s]\n"
                 "%s=%s\n"