Add by_id and get_id functions, renaming from *_uid.

`UID` sounds like `User ID`. While it is a Unique ID, the property of an
"identifier" is generally that it identifies a unique thing, so the 'U'
is redundant, and `GUID` as a globally unique id (which is likely also
true for these IDs) has a specific meaning and syntax, so we're not using
that. So, we just say conference `id`.

toxcore/tox.api.h

@@ -245,9 +245,16 @@ const SECRET_KEY_SIZE              = 32;
 
 /**
  * The size of a Tox Conference unique id in bytes.
+ *
+ * @deprecated Use $CONFERENCE_ID_SIZE instead.
  */
 const CONFERENCE_UID_SIZE          = 32;
 
+/**
+ * The size of a Tox Conference unique id in bytes.
+ */
+const CONFERENCE_ID_SIZE           = 32;
+
 /**
  * The size of the nospam in bytes when written in a Tox address.
  */
@@ -2461,6 +2468,32 @@ namespace conference {
     }
   }
 
+  /**
+   * Get the conference unique ID.
+   *
+   * If id is NULL, this function has no effect.
+   *
+   * @param id A memory region large enough to store $CONFERENCE_ID_SIZE bytes.
+   *
+   * @return true on success.
+   */
+  const bool get_id(uint32_t conference_number, uint8_t[CONFERENCE_ID_SIZE] id);
+
+  /**
+   * Return the conference number associated with the specified id.
+   *
+   * @param id A byte array containing the conference id ($CONFERENCE_ID_SIZE).
+   *
+   * @return the conference number on success, an unspecified value on failure.
+   */
+  const uint32_t by_id(const uint8_t[CONFERENCE_ID_SIZE] id) {
+    NULL,
+    /**
+     * No conference with the given id exists on the conference list.
+     */
+    NOT_FOUND,
+  }
+
   /**
    * Get the conference unique ID.
    *
@@ -2469,6 +2502,7 @@ namespace conference {
    * @param uid A memory region large enough to store $CONFERENCE_UID_SIZE bytes.
    *
    * @return true on success.
+   * @deprecated use $get_id instead (exactly the same function, just renamed).
    */
   const bool get_uid(uint32_t conference_number, uint8_t[CONFERENCE_UID_SIZE] uid);
 
@@ -2478,6 +2512,7 @@ namespace conference {
    * @param uid A byte array containing the conference id ($CONFERENCE_UID_SIZE).
    *
    * @return the conference number on success, an unspecified value on failure.
+   * @deprecated use $by_id instead (exactly the same function, just renamed).
    */
   const uint32_t by_uid(const uint8_t[CONFERENCE_UID_SIZE] uid) {
     NULL,
@@ -2678,6 +2713,7 @@ typedef TOX_ERR_FILE_SEND_CHUNK Tox_Err_File_Send_Chunk;
 typedef TOX_ERR_CONFERENCE_NEW Tox_Err_Conference_New;
 typedef TOX_ERR_CONFERENCE_DELETE Tox_Err_Conference_Delete;
 typedef TOX_ERR_CONFERENCE_PEER_QUERY Tox_Err_Conference_Peer_Query;
+typedef TOX_ERR_CONFERENCE_BY_ID Tox_Err_Conference_By_Id;
 typedef TOX_ERR_CONFERENCE_BY_UID Tox_Err_Conference_By_Uid;
 typedef TOX_ERR_CONFERENCE_INVITE Tox_Err_Conference_Invite;
 typedef TOX_ERR_CONFERENCE_JOIN Tox_Err_Conference_Join;

toxcore/tox.c

@@ -1457,31 +1457,60 @@ Tox_Conference_Type tox_conference_get_type(const Tox *tox, uint32_t conference_
     return (Tox_Conference_Type)ret;
 }
 
-bool tox_conference_get_uid(const Tox *tox, uint32_t conference_number, uint8_t *uid /* TOX_CONFERENCE_ID_SIZE bytes */)
+bool tox_conference_get_id(const Tox *tox, uint32_t conference_number, uint8_t *id /* TOX_CONFERENCE_ID_SIZE bytes */)
 {
     const Messenger *m = tox;
-    return conference_get_uid((Group_Chats *)m->conferences_object, conference_number, uid);
+    return conference_get_uid((Group_Chats *)m->conferences_object, conference_number, id);
 }
 
-uint32_t tox_conference_by_uid(const Tox *tox, const uint8_t *uid, Tox_Err_Conference_By_Uid *error)
+// TODO(iphydf): Delete in 0.3.0.
+bool tox_conference_get_uid(const Tox *tox, uint32_t conference_number, uint8_t *uid /* TOX_CONFERENCE_ID_SIZE bytes */)
 {
-    if (!uid) {
+    return tox_conference_get_id(tox, conference_number, uid);
-        SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_UID_NULL);
+}
+
+uint32_t tox_conference_by_id(const Tox *tox, const uint8_t *id, Tox_Err_Conference_By_Id *error)
+{
+    if (!id) {
+        SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_ID_NULL);
         return UINT32_MAX;
     }
 
     const Messenger *m = tox;
-    int32_t ret = conference_by_uid((Group_Chats *)m->conferences_object, uid);
+    int32_t ret = conference_by_uid((Group_Chats *)m->conferences_object, id);
 
     if (ret == -1) {
-        SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_UID_NOT_FOUND);
+        SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_ID_NOT_FOUND);
         return UINT32_MAX;
     }
 
-    SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_UID_OK);
+    SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_ID_OK);
     return ret;
 }
 
+// TODO(iphydf): Delete in 0.3.0.
+uint32_t tox_conference_by_uid(const Tox *tox, const uint8_t *uid, Tox_Err_Conference_By_Uid *error)
+{
+    Tox_Err_Conference_By_Id id_error;
+    const uint32_t res = tox_conference_by_id(tox, uid, &id_error);
+
+    switch (id_error) {
+        case TOX_ERR_CONFERENCE_BY_ID_OK:
+            SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_UID_OK);
+            break;
+
+        case TOX_ERR_CONFERENCE_BY_ID_NULL:
+            SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_UID_NULL);
+            break;
+
+        case TOX_ERR_CONFERENCE_BY_ID_NOT_FOUND:
+            SET_ERROR_PARAMETER(error, TOX_ERR_CONFERENCE_BY_UID_NOT_FOUND);
+            break;
+    }
+
+    return res;
+}
+
 static void set_custom_packet_error(int ret, Tox_Err_Friend_Custom_Packet *error)
 {
     switch (ret) {

toxcore/tox.h

@@ -250,11 +250,20 @@ uint32_t tox_secret_key_size(void);
 
 /**
  * The size of a Tox Conference unique id in bytes.
+ *
+ * @deprecated Use TOX_CONFERENCE_ID_SIZE instead.
  */
 #define TOX_CONFERENCE_UID_SIZE        32
 
 uint32_t tox_conference_uid_size(void);
 
+/**
+ * The size of a Tox Conference unique id in bytes.
+ */
+#define TOX_CONFERENCE_ID_SIZE         32
+
+uint32_t tox_conference_id_size(void);
+
 /**
  * The size of the nospam in bytes when written in a Tox address.
  */
@@ -2814,6 +2823,46 @@ typedef enum TOX_ERR_CONFERENCE_GET_TYPE {
 TOX_CONFERENCE_TYPE tox_conference_get_type(const Tox *tox, uint32_t conference_number,
         TOX_ERR_CONFERENCE_GET_TYPE *error);
 
+/**
+ * Get the conference unique ID.
+ *
+ * If id is NULL, this function has no effect.
+ *
+ * @param id A memory region large enough to store TOX_CONFERENCE_ID_SIZE bytes.
+ *
+ * @return true on success.
+ */
+bool tox_conference_get_id(const Tox *tox, uint32_t conference_number, uint8_t *id);
+
+typedef enum TOX_ERR_CONFERENCE_BY_ID {
+
+    /**
+     * The function returned successfully.
+     */
+    TOX_ERR_CONFERENCE_BY_ID_OK,
+
+    /**
+     * One of the arguments to the function was NULL when it was not expected.
+     */
+    TOX_ERR_CONFERENCE_BY_ID_NULL,
+
+    /**
+     * No conference with the given id exists on the conference list.
+     */
+    TOX_ERR_CONFERENCE_BY_ID_NOT_FOUND,
+
+} TOX_ERR_CONFERENCE_BY_ID;
+
+
+/**
+ * Return the conference number associated with the specified id.
+ *
+ * @param id A byte array containing the conference id (TOX_CONFERENCE_ID_SIZE).
+ *
+ * @return the conference number on success, an unspecified value on failure.
+ */
+uint32_t tox_conference_by_id(const Tox *tox, const uint8_t *id, TOX_ERR_CONFERENCE_BY_ID *error);
+
 /**
  * Get the conference unique ID.
  *
@@ -2822,6 +2871,7 @@ TOX_CONFERENCE_TYPE tox_conference_get_type(const Tox *tox, uint32_t conference_
  * @param uid A memory region large enough to store TOX_CONFERENCE_UID_SIZE bytes.
  *
  * @return true on success.
+ * @deprecated use tox_conference_get_id instead (exactly the same function, just renamed).
  */
 bool tox_conference_get_uid(const Tox *tox, uint32_t conference_number, uint8_t *uid);
 
@@ -2851,6 +2901,7 @@ typedef enum TOX_ERR_CONFERENCE_BY_UID {
  * @param uid A byte array containing the conference id (TOX_CONFERENCE_UID_SIZE).
  *
  * @return the conference number on success, an unspecified value on failure.
+ * @deprecated use tox_conference_by_id instead (exactly the same function, just renamed).
  */
 uint32_t tox_conference_by_uid(const Tox *tox, const uint8_t *uid, TOX_ERR_CONFERENCE_BY_UID *error);
 
@@ -3054,6 +3105,7 @@ typedef TOX_ERR_FILE_SEND_CHUNK Tox_Err_File_Send_Chunk;
 typedef TOX_ERR_CONFERENCE_NEW Tox_Err_Conference_New;
 typedef TOX_ERR_CONFERENCE_DELETE Tox_Err_Conference_Delete;
 typedef TOX_ERR_CONFERENCE_PEER_QUERY Tox_Err_Conference_Peer_Query;
+typedef TOX_ERR_CONFERENCE_BY_ID Tox_Err_Conference_By_Id;
 typedef TOX_ERR_CONFERENCE_BY_UID Tox_Err_Conference_By_Uid;
 typedef TOX_ERR_CONFERENCE_INVITE Tox_Err_Conference_Invite;
 typedef TOX_ERR_CONFERENCE_JOIN Tox_Err_Conference_Join;