add xml error checking

diff --git a/src/switch_xml.c b/src/switch_xml.c
index efda5dbe12b107a80be0189756309105ecbb4956..947a3060e9dad6f51a27444bfbe3bebc47b9bf76 100644 (file)
--- a/src/switch_xml.c
+++ b/src/switch_xml.c
@@ -403,6 +403,10 @@ SWITCH_DECLARE(const char *) switch_xml_attr(switch_xml_t xml, const char *attr)
                return NULL;
        }
 
+       if (!root->attr) {
+               return NULL;
+       }
+       
        for (i = 0; root->attr[i] && xml->name && strcmp(xml->name, root->attr[i][0]); i++);
        if (!root->attr[i])
                return NULL;                    /* no matching default attributes */
@@ -451,6 +455,9 @@ SWITCH_DECLARE(const char **) switch_xml_pi(switch_xml_t xml, const char *target
                return (const char **) SWITCH_XML_NIL;
        while (root->xml.parent)
                root = (switch_xml_root_t) root->xml.parent;    /* root tag */
+       if (!root || !root->pi) {
+               return (const char **) SWITCH_XML_NIL;
+       }
        while (root->pi[i] && strcmp(target, root->pi[i][0]))
                i++;                                    /* find target */
        return (const char **) ((root->pi[i]) ? root->pi[i] + 1 : SWITCH_XML_NIL);
@@ -463,6 +470,10 @@ static switch_xml_t switch_xml_err(switch_xml_root_t root, char *s, const char *
        int line = 1;
        char *t, fmt[SWITCH_XML_ERRL];
 
+       if (!root || !root->s) {
+               return NULL;
+       }
+
        for (t = root->s; t && t < s; t++)
                if (*t == '\n')
                        line++;
@@ -578,7 +589,13 @@ static char *switch_xml_decode(char *s, char **ent, char t)
 /* called when parser finds start of new tag */
 static void switch_xml_open_tag(switch_xml_root_t root, char *name, char **attr)
 {
-       switch_xml_t xml = root->cur;
+       switch_xml_t xml;
+
+       if (!root || !root->cur) {
+               return;
+       }
+
+       xml = root->cur;
 
        if (xml->name)
                xml = switch_xml_add_child(xml, name, strlen(xml->txt));
@@ -592,10 +609,16 @@ static void switch_xml_open_tag(switch_xml_root_t root, char *name, char **attr)
 /* called when parser finds character content between open and closing tag */
 static void switch_xml_char_content(switch_xml_root_t root, char *s, switch_size_t len, char t)
 {
-       switch_xml_t xml = root->cur;
+       switch_xml_t xml;
        char *m = s;
        switch_size_t l;
 
+       if (!root || !root->cur) {
+               return;
+       }
+
+       xml = root->cur;
+
        if (!xml || !xml->name || !len)
                return;                                 /* sanity check */
 
@@ -632,7 +655,7 @@ static void switch_xml_char_content(switch_xml_root_t root, char *s, switch_size
 /* called when parser finds closing tag */
 static switch_xml_t switch_xml_close_tag(switch_xml_root_t root, char *name, char *s)
 {
-       if (!root->cur || !root->cur->name || strcmp(name, root->cur->name))
+       if (!root || !root->cur || !root->cur->name || strcmp(name, root->cur->name))
                return switch_xml_err(root, s, "unexpected closing tag </%s>", name);
 
        root->cur = root->cur->parent;
@@ -681,7 +704,7 @@ static void switch_xml_proc_inst(switch_xml_root_t root, char *s, switch_size_t
                return;
        }
 
-       if (!root->pi[0]) {
+       if (!root->pi || !root->pi[0]) {
                root->pi = (char ***) malloc(sizeof(char **));
                if (!root->pi)
                        return;