change the guid mapping code to use a tree isntead of a hashtable

svn path=/trunk/; revision=18946

1 files changed, 124 insertions, 101 deletions

diff --git a/epan/guid-utils.c b/epan/guid-utils.c
index eb2f8e7f42..0cd36b0ebf 100644
--- a/epan/guid-utils.c
+++ b/epan/guid-utils.c
@@ -32,6 +32,7 @@
 #include <glib.h>
 #include <epan/epan.h>
 #include <epan/strutil.h>
+#include <epan/emem.h>
 #include "guid-utils.h"
 
 #ifdef _WIN32
@@ -39,33 +40,126 @@
 #include <windows.h>
 #endif
 
+static emem_tree_t *guid_to_name_tree = NULL;
 
-/* GUID "registry" */
-typedef struct _guid_key {
-    e_guid_t guid;
-} guid_key;
 
-typedef struct _guid_value {
-    const gchar *name;
-} guid_value;
+/* store a guid to name mapping */
+void 
+guids_add_guid(e_guid_t *guid, const gchar *name)
+{
+	emem_tree_key_t guidkey[2];
+	guint32 g[4];
+
+	g[0]=guid->data1;
+
+	g[1]=guid->data2;
+	g[1]<<=16;
+	g[1]|=guid->data3;
+
+	g[2]=guid->data4[0];
+	g[2]<<=8;
+	g[2]|=guid->data4[1];
+	g[2]<<=8;
+	g[2]|=guid->data4[2];
+	g[2]<<=8;
+	g[2]|=guid->data4[3];
+
+	g[3]=guid->data4[4];
+	g[3]<<=8;
+	g[3]|=guid->data4[5];
+	g[3]<<=8;
+	g[3]|=guid->data4[6];
+	g[3]<<=8;
+	g[3]|=guid->data4[7];
+
+	guidkey[0].key=g;
+	guidkey[0].length=4;
+	guidkey[1].length=0;
+	
+	pe_tree_insert32_array(guid_to_name_tree, &guidkey[0], name);
+}
+
+
+/* retreive the registered name for this GUID */
+const gchar *
+guids_get_guid_name(e_guid_t *guid)
+{
+	emem_tree_key_t guidkey[2];
+	guint32 g[4];
+	char *name;
+#ifdef _WIN32
+	static char *uuid_name;
+#endif
+
+	g[0]=guid->data1;
+
+	g[1]=guid->data2;
+	g[1]<<=16;
+	g[1]|=guid->data3;
+
+	g[2]=guid->data4[0];
+	g[2]<<=8;
+	g[2]|=guid->data4[1];
+	g[2]<<=8;
+	g[2]|=guid->data4[2];
+	g[2]<<=8;
+	g[2]|=guid->data4[3];
+
+	g[3]=guid->data4[4];
+	g[3]<<=8;
+	g[3]|=guid->data4[5];
+	g[3]<<=8;
+	g[3]|=guid->data4[6];
+	g[3]<<=8;
+	g[3]|=guid->data4[7];
+
+	guidkey[0].key=g;
+	guidkey[0].length=4;
+	guidkey[1].length=0;
+	
+	if((name = pe_tree_lookup32_array(guid_to_name_tree, &guidkey[0]))){
+		return name;
+	}
+
+#ifdef _WIN32
+	/* try to resolve the mapping from the Windows registry */
+	/* XXX - prefill the resolving database with all the Windows registry entries once at init only (instead of searching each time)? */
+	uuid_name=ep_alloc(128);
+	if(ResolveWin32UUID(*guid, uuid_name, 128)) {
+		return uuid_name;
+	}
+#endif
+
+	return NULL;
+}
 
 
-/* global guid to name collection */
-GHashTable *guids = NULL;
+void 
+guids_init(void)
+{
+	guid_to_name_tree=pe_tree_create(EMEM_TREE_TYPE_RED_BLACK, "guid_to_name");
+	/* XXX here is a good place to read a config file with wellknown guids */
+}
+
 
 
 #ifdef _WIN32
 /* try to resolve an DCE/RPC interface name to it's name using the Windows registry entries */
 /* XXX - might be better to fill all interfaces into our database at startup instead of searching each time */
-int ResolveWin32UUID(e_guid_t if_id, char *uuid_name, int uuid_name_max_len)
+int 
+ResolveWin32UUID(e_guid_t if_id, char *uuid_name, int uuid_name_max_len)
 {
-	TCHAR reg_uuid_name[MAX_PATH];
+	TCHAR *reg_uuid_name;
 	HKEY hKey = NULL;
 	DWORD uuid_max_size = MAX_PATH;
-	TCHAR reg_uuid_str[MAX_PATH];
+	TCHAR *reg_uuid_str;
+
+	reg_uuid_name=ep_alloc(MAX_PATH*sizeof(TCHAR));
+	reg_uuid_str=ep_alloc(MAX_PATH*sizeof(TCHAR));
 
-	if(uuid_name_max_len < 2)
+	if(uuid_name_max_len < 2){
 		return 0;
+	}
 	reg_uuid_name[0] = '\0';
 	_snwprintf(reg_uuid_str, MAX_PATH, _T("SOFTWARE\\Classes\\Interface\\{%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x}"),
 			if_id.data1, if_id.data2, if_id.data3,
@@ -73,10 +167,8 @@ int ResolveWin32UUID(e_guid_t if_id, char *uuid_name, int uuid_name_max_len)
 			if_id.data4[2], if_id.data4[3],
 			if_id.data4[4], if_id.data4[5],
 			if_id.data4[6], if_id.data4[7]);
-	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, reg_uuid_str, 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS)
-	{
-		if (RegQueryValueEx(hKey, NULL, NULL, NULL, (LPBYTE)reg_uuid_name, &uuid_max_size) == ERROR_SUCCESS && uuid_max_size <= MAX_PATH)
-			{
+	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, reg_uuid_str, 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS) {
+		if (RegQueryValueEx(hKey, NULL, NULL, NULL, (LPBYTE)reg_uuid_name, &uuid_max_size) == ERROR_SUCCESS && uuid_max_size <= MAX_PATH) {
 			g_snprintf(uuid_name, uuid_name_max_len, "%s", utf_16to8(reg_uuid_name));
 			RegCloseKey(hKey);
 			return strlen(uuid_name);
@@ -89,99 +181,30 @@ int ResolveWin32UUID(e_guid_t if_id, char *uuid_name, int uuid_name_max_len)
 #endif
 
 
+
 /* Tries to match a guid against its name.
    Returns the associated string ptr on a match.
    Formats uuid number and returns the resulting string, if name is unknown.
    (derived from val_to_str) */
-const gchar* guids_resolve_guid_to_str(e_guid_t *guid) {
-  const gchar *ret;
-  static gchar  str[3][64];
-  static gchar *cur;
-
-
-  ret = guids_get_guid_name(guid);
-  if (ret != NULL)
-    return ret;
-  if (cur == &str[0][0]) {
-    cur = &str[1][0];
-  } else if (cur == &str[1][0]) {  
-    cur = &str[2][0];
-  } else {  
-    cur = &str[0][0];
-  }
-  g_snprintf(cur, 64, "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
+const gchar *
+guids_resolve_guid_to_str(e_guid_t *guid)
+{
+	const gchar *name;
+
+	name=guids_get_guid_name(guid);
+	if(name){
+		return name;
+	}
+
+
+	name=ep_alloc(64);
+	g_snprintf(name, 64, "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                       guid->data1, guid->data2, guid->data3,
                       guid->data4[0], guid->data4[1],
                       guid->data4[2], guid->data4[3],
                       guid->data4[4], guid->data4[5],
                       guid->data4[6], guid->data4[7]);
-  return cur;
-}
-
-
-static gint
-guid_equal (gconstpointer k1, gconstpointer k2)
-{
-    const guid_key *key1 = (const guid_key *)k1;
-    const guid_key *key2 = (const guid_key *)k2;
-    return ((memcmp (&key1->guid, &key2->guid, sizeof (e_guid_t)) == 0));
-}
-
-static guint
-guid_hash (gconstpointer k)
-{
-    const guid_key *key = (const guid_key *)k;
-    /* This isn't perfect, but the Data1 part of these is almost always
-       unique. */
-    return key->guid.data1;
-}
-
-void guids_init(void)
-{
-    g_assert(guids == NULL);
-
-    guids = g_hash_table_new (guid_hash, guid_equal);
-}
-
-void guids_add_guid(e_guid_t *guid, const gchar *name)
-{
-    guid_key *key = g_malloc (sizeof (*key));
-    guid_value *value = g_malloc (sizeof (*value));
-
-    key->guid = *guid;
-
-    /* XXX - do we need to copy the name? */
-    value->name = name;
-
-    g_hash_table_insert (guids, key, value);
+	return name;
 }
 
 
-/* try to get registered name for this GUID */
-const gchar *guids_get_guid_name(e_guid_t *guid)
-{
-    guid_key key;
-    guid_value *value;
-#ifdef _WIN32
-    /* XXX - we need three time circulating buffer here */
-    /* XXX - is there a maximum length of the name? */
-    static char uuid_name[128];
-#endif
-
-	/* try to get registered guid "name" of guid */
-	key.guid = *guid;
-
-    if ((value = g_hash_table_lookup (guids, &key)) != NULL) {
-		return value->name;
-	}
-
-#ifdef _WIN32
-    /* try to resolve the mapping from the Windows registry */
-    /* XXX - prefill the resolving database with all the Windows registry entries once at init only (instead of searching each time)? */
-    if(ResolveWin32UUID(*guid, uuid_name, 128)) {
-        return uuid_name;
-    }
-#endif
-
-	return NULL;
-}