misc

Signed-off-by: Mattias Andrée <maandree@operamail.com>

6 files changed, 657 insertions, 10 deletions

diff --git a/Makefile b/Makefile
index 18c810e..7b9bc0b 100644
--- a/Makefile
+++ b/Makefile
@@ -70,7 +70,7 @@ C_FLAGS = $(OPTIMISE) $(WARN) -std=$(STD) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS)  \
 
 
 # Object files for the libary
-LIBOBJ = linked-list hash-table fd-table mds-message util
+LIBOBJ = linked-list client-list hash-table fd-table mds-message util
 
 # Servers and utilities.
 SERVERS = mds mds-respawn mds-server mds-echo mds-registry
diff --git a/doc/protocols b/doc/protocols
index 449f669..fe6ca16 100644
--- a/doc/protocols
+++ b/doc/protocols
@@ -77,7 +77,10 @@ Conditionally required header: Length
 
 Optional header: Action
   Remove availability for registry if `remove`.
-  Wait until listed commands are available if `wait`.
+  Wait until listed commands are available if `wait`,
+    however if a protocol becomes unavailable during this
+    wait period it will still be counted as available for
+    this wait action.
   Send a list of availability commands if `list`.
 
 Message: List of values for the header `Command` that you implement
@@ -93,3 +96,17 @@ Reference implementation: mds-registry
 
 ---------------------------------------------------------------------
 
+Command: reregister
+  Request that all servers resends `Command: register` with either
+  `Action: add` or without the `Action` header (does the same thing)
+
+Purpose: Rebuild registry created with `Command: register` if the
+	 registry server crashes
+
+Compulsivity: highly recommended (infrastructure), programs may
+	      think a protocol is not supported of the registry
+	      server crashes if you do not implement this in your
+	      server
+
+---------------------------------------------------------------------
+
diff --git a/src/libmdsserver/client-list.c b/src/libmdsserver/client-list.c
new file mode 100644
index 0000000..0e1a2ab
--- /dev/null
+++ b/src/libmdsserver/client-list.c
@@ -0,0 +1,241 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "client-list.h"
+
+#include "macros.h"
+
+#include <string.h>
+#include <errno.h>
+
+
+/**
+ * The default initial capacity
+ */
+#ifndef CLIENT_LIST_DEFAULT_INITIAL_CAPACITY
+#define CLIENT_LIST_DEFAULT_INITIAL_CAPACITY  8
+#endif
+
+
+/**
+ * Computes the nearest, but higher, power of two,
+ * but only if the current value is not a power of two
+ * 
+ * @param   value  The value to be rounded up to a power of two
+ * @return         The nearest, but not smaller, power of two
+ */
+static size_t to_power_of_two(size_t value)
+{
+  value -= 1;
+  value |= value >> 1;
+  value |= value >> 2;
+  value |= value >> 4;
+  value |= value >> 8;
+  value |= value >> 16;
+#if __WORDSIZE == 64
+  value |= value >> 32;
+#endif
+  return value + 1;
+}
+
+
+/**
+ * Create a client list
+ * 
+ * @param   this      Memory slot in which to store the new client list
+ * @param   capacity  The minimum initial capacity of the client list, 0 for default
+ * @return            Non-zero on error, `errno` will have been set accordingly
+ */
+int client_list_create(client_list_t* restrict this, size_t capacity)
+{
+  /* Use default capacity of zero is specified. */
+  if (capacity == 0)
+    capacity = CLIENT_LIST_DEFAULT_INITIAL_CAPACITY;
+  
+  /* Initialise the client list. */
+  this->capacity   = capacity = to_power_of_two(capacity);
+  this->size       = 0;
+  this->clients     = NULL;
+  if (xmalloc(this->clients, capacity, uint64_t))
+    return -1;
+  
+  return 0;
+}
+
+
+/**
+ * Release all resources in a client list, should
+ * be done even if `client_list_create` fails
+ * 
+ * @param  this  The client list
+ */
+void client_list_destroy(client_list_t* restrict this)
+{
+  free(this->clients);
+  this->clients = NULL;
+}
+
+
+/**
+ * Clone a client list
+ * 
+ * @param   this  The client list to clone
+ * @param   out   Memory slot in which to store the new client list
+ * @return        Non-zero on error, `errno` will have been set accordingly
+ */
+int client_list_clone(const client_list_t* restrict this, client_list_t* restrict out)
+{
+  size_t n = this->capacity * sizeof(uint64_t);
+  uint64_t* restrict new_clients = NULL;
+  
+  out->clients = NULL;
+  
+  if ((new_clients = malloc(n)) == NULL)
+    goto fail;
+  
+  out->clients = new_clients;
+  
+  out->capacity = this->capacity;
+  out->size     = this->size;
+  
+  memcpy(out->clients, this->clients, n);
+  
+  return 0;
+  
+ fail:
+  free(new_clients);
+  return -1;
+}
+
+
+/**
+ * Add a client to the list
+ * 
+ * @param   this    The list
+ * @param   client  The client to add
+ * @return          Non-zero on error, errno will be set accordingly
+ */
+int client_list_add(client_list_t* restrict this, uint64_t client)
+{
+  if (this->size == this->capacity)
+    {
+      uint64_t* old = this->clients;
+      if (xrealloc(old, this->capacity <<= 1, uint64_t))
+	{
+	  this->capacity >>= 1;
+	  this->clients = old;
+	  return -1;
+	}
+    }
+  
+  this->clients[this->size++] = client;
+  return 0;
+}
+
+
+/**
+ * Remove a client from the list, once
+ * 
+ * @param  this    The list
+ * @param  client  The client to remove
+ */
+void client_list_remove(client_list_t* restrict this, uint64_t client)
+{
+  size_t i;
+  for (i = 0; i < this->size; i++)
+    {
+      if (this->clients[i] == client)
+	{
+	  size_t n = (--(this->size) - i) * sizeof(uint64_t);
+	  memmove(this->clients + i, this->clients + i + 1, n);
+	  
+	  if (this->size << 1 <= this->capacity)
+	    {
+	      uint64_t* old = this->clients;
+	      if (xrealloc(old, this->capacity >>= 1, uint64_t))
+		{
+		  this->capacity <<= 1;
+		  this->clients = old;
+		}
+	    }
+	  
+	  return;
+	}
+    }
+}
+
+
+/**
+ * Calculate the buffer size need to marshal a client list
+ * 
+ * @param   this  The list
+ * @return        The number of bytes to allocate to the output buffer
+ */
+size_t client_list_marshal_size(const client_list_t* restrict this)
+{
+  return 2 * sizeof(size_t) + this->size * sizeof(uint64_t) + sizeof(int);
+}
+
+
+/**
+ * Marshals a client list
+ * 
+ * @param  this  The list
+ * @param  data  Output buffer for the marshalled data
+ */
+void client_list_marshal(const client_list_t* restrict this, char* restrict data)
+{
+  buf_set_next(data, int, CLIENT_LIST_T_VERSION);
+  buf_set_next(data, size_t, this->capacity);
+  buf_set_next(data, size_t, this->size);
+  
+  memcpy(data, this->clients, this->size * sizeof(uint64_t));
+}
+
+
+/**
+ * Unmarshals a client list
+ * 
+ * @param   this  Memory slot in which to store the new client list
+ * @param   data  In buffer with the marshalled data
+ * @return        Non-zero on error, errno will be set accordingly.
+ *                Destroy the list on error.
+ */
+int client_list_unmarshal(client_list_t* restrict this, char* restrict data)
+{
+  size_t n;
+  
+  /* buf_get(data, int, 0, CLIENT_LIST_T_VERSION); */
+  buf_next(data, int, 1);
+  
+  this->clients = NULL;
+  
+  buf_get_next(data, size_t, this->capacity);
+  buf_get_next(data, size_t, this->size);
+  
+  n = this->capacity * sizeof(uint64_t);
+  
+  if ((this->clients = malloc(n)) == NULL)
+    return -1;
+  
+  n = this->size * sizeof(uint64_t);
+  
+  memcpy(this->clients, data, n);
+  
+  return 0;
+}
+
diff --git a/src/libmdsserver/client-list.h b/src/libmdsserver/client-list.h
new file mode 100644
index 0000000..1894b63
--- /dev/null
+++ b/src/libmdsserver/client-list.h
@@ -0,0 +1,125 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MDS_LIBMDSSERVER_CLIENT_LIST_H
+#define MDS_LIBMDSSERVER_CLIENT_LIST_H
+
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+
+
+
+#define CLIENT_LIST_T_VERSION  0
+
+/**
+ * Dynamic array of client ID:s
+ */
+typedef struct client_list
+{
+  /**
+   * The size of the array
+   */
+  size_t capacity;
+  
+  /**
+   * The index after the last used index
+   */
+  size_t size;
+  
+  /**
+   * Stored client ID:s
+   */
+  uint64_t* clients;
+  
+} client_list_t;
+
+
+
+/**
+ * Create a client list
+ * 
+ * @param   this      Memory slot in which to store the new client list
+ * @param   capacity  The minimum initial capacity of the client list, 0 for default
+ * @return            Non-zero on error, `errno` will have been set accordingly
+ */
+int client_list_create(client_list_t* restrict this, size_t capacity);
+
+/**
+ * Release all resources in a client list, should
+ * be done even if `client_list_create` fails
+ * 
+ * @param  this  The client list
+ */
+void client_list_destroy(client_list_t* restrict this);
+
+/**
+ * Clone a client list
+ * 
+ * @param   this  The client list to clone
+ * @param   out   Memory slot in which to store the new client list
+ * @return        Non-zero on error, `errno` will have been set accordingly
+ */
+int client_list_clone(const client_list_t* restrict this, client_list_t* restrict out);
+
+/**
+ * Add a client to the list
+ * 
+ * @param   this    The list
+ * @param   client  The client to add
+ * @return          Non-zero on error, errno will be set accordingly
+ */
+int client_list_add(client_list_t* restrict this, uint64_t client);
+
+/**
+ * Remove a client from the list, once
+ * 
+ * @param  this    The list
+ * @param  client  The client to remove
+ */
+void client_list_remove(client_list_t* restrict this, uint64_t client);
+
+/**
+ * Calculate the buffer size need to marshal a client list
+ * 
+ * @param   this  The list
+ * @return        The number of bytes to allocate to the output buffer
+ */
+size_t client_list_marshal_size(const client_list_t* restrict this) __attribute__((pure));
+
+/**
+ * Marshals a client list
+ * 
+ * @param  this  The list
+ * @param  data  Output buffer for the marshalled data
+ */
+void client_list_marshal(const client_list_t* restrict this, char* restrict data);
+
+/**
+ * Unmarshals a client list
+ * 
+ * @param   this  Memory slot in which to store the new client list
+ * @param   data  In buffer with the marshalled data
+ * @return        Non-zero on error, errno will be set accordingly.
+ *                Destroy the list on error.
+ */
+int client_list_unmarshal(client_list_t* restrict this, char* restrict data);
+
+
+#endif
+
diff --git a/src/mds-registry.c b/src/mds-registry.c
index e0d3966..8bd7057 100644
--- a/src/mds-registry.c
+++ b/src/mds-registry.c
@@ -20,6 +20,9 @@
 #include <libmdsserver/macros.h>
 #include <libmdsserver/util.h>
 #include <libmdsserver/mds-message.h>
+#include <libmdsserver/hash-table.h>
+#include <libmdsserver/hash-help.h>
+#include <libmdsserver/client-list.h>
 
 #include <errno.h>
 #include <inttypes.h>
@@ -53,7 +56,7 @@ server_characteristics_t server_characteristics =
 /**
  * Value of the ‘Message ID’ header for the next message
  */
-static int32_t message_id = 1;
+static int32_t message_id = 2;
 
 /**
  * Buffer for received messages
@@ -65,6 +68,11 @@ static mds_message_t received;
  */
 static int connected = 1;
 
+/**
+ * Protocol registry table
+ */
+static hash_table_t reg_table;
+
 
 
 /**
@@ -90,12 +98,25 @@ int initialise_server(void)
   const char* const message =
     "Command: intercept\n"
     "Message ID: 0\n"
-    "Length: 18\n"
+    "Length: 32\n"
     "\n"
-    "Command: register\n";
+    "Command: register\n"
+    "Client closed\n" /* TODO support not implemented yet */
+    
+    "Command: reregister\n"
+    "Message ID: 1\n"
+    "\n";
   
   if (full_send(message, strlen(message)))
     return 1;
+  if (hash_table_create_tuned(&reg_table, 32))
+    {
+      perror(*argv);
+      hash_table_destroy(&reg_table, NULL, NULL);
+      return 1;
+    }
+  reg_table.key_comparator = (compare_func*)string_comparator;
+  reg_table.hasher = (hash_func*)string_hash;
   server_initialised();
   mds_message_initialise(&received);
   return 0;
@@ -173,6 +194,8 @@ int unmarshal_server(char* state_buf)
   r = mds_message_unmarshal(&received, state_buf);
   if (r)
     mds_message_destroy(&received);
+  reg_table.key_comparator = (compare_func*)string_comparator;
+  reg_table.hasher = (hash_func*)string_hash;
   return r;
 }
 
@@ -201,7 +224,7 @@ int master_loop(void)
       int r = mds_message_read(&received, socket_fd);
       if (r == 0)
 	{
-	  r = 0; /* TODO handle message */
+	  r = handle_message();
 	  if (r == 0)
 	    continue;
 	}
@@ -225,6 +248,8 @@ int master_loop(void)
       connected = 1;
     }
   
+  /* TODO if !reexecing or failing, cleanup reg_table */
+  
   mds_message_destroy(&received);
   return 0;
  pfail:
@@ -236,6 +261,222 @@ int master_loop(void)
 
 
 /**
+ * Handle the received message
+ * 
+ * @return  Zero on success -1 on error or interruption,
+ *          errno will be set accordingly
+ */
+int handle_message(void)
+{
+  const char* recv_client_id = NULL;
+  const char* recv_message_id = NULL;
+  const char* recv_length = NULL;
+  const char* recv_action = NULL;
+  size_t i, length = 0;
+  
+#define __get_header(storage, header)  \
+  (startswith(received.headers[i], header))  \
+    storage = received.headers[i] + strlen(header)
+  
+  for (i = 0; i < received.header_count; i++)
+    {
+      if      __get_header(recv_client_id,  "Client ID: ");
+      else if __get_header(recv_message_id, "Message ID: ");
+      else if __get_header(recv_length,     "Length: ");
+      else if __get_header(recv_action,     "Action: ");
+      else
+	continue;
+      if (recv_client_id && recv_message_id && recv_length && recv_action)
+	break;
+    }
+  
+#undef __get_header
+  
+  
+  if ((recv_client_id == NULL) || (strequals(recv_client_id, "0:0")))
+    {
+      eprint("received message from anonymous sender, ignoring.");
+      return 0;
+    }
+  else if (strchr(recv_client_id, ':') == NULL)
+    {
+      eprint("received message from sender without a colon it its ID, ignoring, invalid ID.");
+      return 0;
+    }
+  else if ((recv_length == NULL) && ((recv_action == NULL) || !strequals(recv_action, "list")))
+    {
+      eprint("received empty message without `Action: list`, ignoring, has no effect.");
+      return 0;
+    }
+  else if (recv_message_id == NULL)
+    {
+      eprint("received message with ID, ignoring, master server is misbehaving.");
+      return 0;
+    }
+  
+  
+  if (recv_length != NULL)
+    length = (size_t)atoll(recv_length);
+  if (recv_action != NULL)
+    recv_action = "add";
+  
+#define __registry_action(action)  registry_action(length, action, recv_client_id, recv_message_id)
+  
+  if      (strequals(recv_action, "add"))     return __registry_action(1);
+  else if (strequals(recv_action, "remove"))  return __registry_action(-1);
+  else if (strequals(recv_action, "wait"))    return __registry_action(0);
+  else if (strequals(recv_action, "list"))    return list_registry(recv_client_id, recv_message_id);
+  else
+    {
+      eprint("received invalid action, ignoring.");
+      return 0;
+    }
+  
+#undef __registry_action
+}
+
+
+/**
+ * Perform an action over the registry
+ * 
+ * @param   length           The length of the received message
+ * @param   action           -1 to remove command, +1 to add commands, 0 to
+ *                           wait until the message commnds are registered
+ * @param   recv_client_id   The ID of the client
+ * @param   recv_message_id  The ID of the received message
+ * @return                   Zero on success -1 on error or interruption,
+ *                           errno will be set accordingly
+ */
+int registry_action(size_t length, int action, const char* recv_client_id, const char* recv_message_id)
+{
+  char* payload = received.payload;
+  uint64_t client = 0;
+  hash_table_t* wait_set = NULL;
+  size_t begin;
+  char client_words[22];
+  char* client_high;
+  char* client_low;
+  
+  if (action)
+    {
+      strcpy(client_high = client_words, recv_client_id);
+      client_low = rawmemchr(client_words, ':');
+      *client_low++ = '\0';
+      client = (uint64_t)atoll(client_high);
+      client <<= 32;
+      client |= (uint64_t)atoll(client_low);
+    }
+  else
+    {
+      wait_set = malloc(sizeof(hash_table_t));
+      if (hash_table_create(wait_set))
+	{
+	  perror(*argv);
+	  hash_table_destroy(wait_set, NULL, NULL);
+	  free(wait_set);
+	  return -1;
+	}
+      wait_set->key_comparator = (compare_func*)string_comparator;
+      wait_set->hasher = (hash_func*)string_hash;
+    }
+  
+  if (received.payload_size == length)
+    {
+      if (xrealloc(received.payload, received.payload_size <<= 1, char))
+	{
+	  received.payload = payload;
+	  received.payload_size >>= 1;
+	  perror(*argv);
+	  if (wait_set != NULL)
+	    {
+	      hash_table_destroy(wait_set, NULL, NULL);
+	      free(wait_set);
+	    }
+	  return -1;
+	}
+      else
+	payload = received.payload;
+    }
+  
+  payload[length] = '\n';
+  
+  for (begin = 0; begin < length;)
+    {
+      char* end = rawmemchr(payload + begin, '\n');
+      size_t len = (size_t)(end - payload) - begin - 1;
+      char* command = payload + begin;
+      size_t command_key = (size_t)(void*)command;
+      
+      command[len] = '\0';
+      begin += len + 1;
+      
+      if (action == 1)
+	if (hash_table_contains_key(&reg_table, command_key))
+	  {
+	    size_t address = hash_table_get(&reg_table, command_key);
+	    client_list_t* list = (client_list_t*)(void*)address;
+	    if (client_list_add(list, client) < 0)
+	      return -1;
+	  }
+	else
+	  {
+	    client_list_t* list = malloc(sizeof(client_list_t));
+	    void* address = list;
+	    if (list == NULL)
+	      return perror(*argv), -1;
+	    if (client_list_create(list, 1) ||
+		client_list_add(list, client) ||
+		(hash_table_put(&reg_table, command_key, (size_t)address) == 0))
+	      {
+		perror(*argv);
+		client_list_destroy(list);
+		free(list);
+		return -1;
+	      }
+	  }
+      else if ((action == -1) && hash_table_contains_key(&reg_table, command_key))
+	{
+	  size_t address = hash_table_get(&reg_table, command_key);
+	  client_list_t* list = (client_list_t*)(void*)address;
+	  client_list_remove(list, client);
+	}
+      else if ((action == 0) && !hash_table_contains_key(&reg_table, command_key))
+	{
+	  if (hash_table_put(wait_set, command_key, 1) == 0)
+	    if (errno)
+	      {
+		perror(*argv);
+		hash_table_destroy(wait_set, NULL, NULL);
+		free(wait_set);
+		return -1;
+	      }
+	}
+    }
+  
+  if (action == 0)
+    {
+      /* TODO */
+    }
+  
+  return 0;
+}
+
+
+/**
+ * Send a list of all registered commands to a client
+ * 
+ * @param   recv_client_id   The ID of the client
+ * @param   recv_message_id  The ID of the received message
+ * @return                   Zero on success -1 on error or interruption,
+ *                           errno will be set accordingly
+ */
+int list_registry(const char* recv_client_id, const char* recv_message_id)
+{
+  /* TODO */
+}
+
+
+/**
  * Send a full message even if interrupted
  * 
  * @param   message  The message to send
diff --git a/src/mds-registry.h b/src/mds-registry.h
index 34a12e9..c8ced44 100644
--- a/src/mds-registry.h
+++ b/src/mds-registry.h
@@ -15,20 +15,43 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#ifndef MDS_MDS_ECHO_H
-#define MDS_MDS_ECHO_H
+#ifndef MDS_MDS_REGISTRY_H
+#define MDS_MDS_REGISTRY_H
 
 
 #include "mds-base.h"
 
 
 /**
- * Echo the received message payload
+ * Handle the received message
  * 
  * @return  Zero on success -1 on error or interruption,
  *          errno will be set accordingly
  */
-int echo_message(void);
+int handle_message(void);
+
+/**
+ * Perform an action over the registry
+ * 
+ * @param   length           The length of the received message
+ * @param   action           -1 to remove command, +1 to add commands, 0 to
+ *                           wait until the message commnds are registered
+ * @param   recv_client_id   The ID of the client
+ * @param   recv_message_id  The ID of the received message
+ * @return                   Zero on success -1 on error or interruption,
+ *                           errno will be set accordingly
+ */
+int registry_action(size_t length, int action, const char* recv_client_id, const char* recv_message_id);
+
+/**
+ * Send a list of all registered commands to a client
+ * 
+ * @param   recv_client_id   The ID of the client
+ * @param   recv_message_id  The ID of the received message
+ * @return                   Zero on success -1 on error or interruption,
+ *                           errno will be set accordingly
+ */
+int list_registry(const char* recv_client_id, const char* recv_message_id);
 
 /**
  * Send a full message even if interrupted