merge track-errors and resolve conflict

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

11 files changed, 128 insertions, 119 deletions

diff --git a/src/mds-server/client.c b/src/mds-server/client.c
index 99d561e..f72a2ce 100644
--- a/src/mds-server/client.c
+++ b/src/mds-server/client.c
@@ -82,16 +82,18 @@ int client_initialise_threading(client_t* restrict this)
   
   /* Create mutex to make sure two thread to not try to send
      messages concurrently, and other client local actions. */
-  if ((errno = pthread_mutex_init(&(this->mutex), NULL)))         return -1;
+  fail_if ((errno = pthread_mutex_init(&(this->mutex), NULL)));
   this->mutex_created = 1;
   
   /* Create mutex and codition for multicast interception replies. */
-  if ((errno = pthread_mutex_init(&(this->modify_mutex), NULL)))  return -1;
+  fail_if ((errno = pthread_mutex_init(&(this->modify_mutex), NULL)));
   this->modify_mutex_created = 1;
-  if ((errno = pthread_cond_init(&(this->modify_cond), NULL)))    return -1;
+  fail_if ((errno = pthread_cond_init(&(this->modify_cond), NULL)));
   this->modify_cond_created = 1;
   
   return 0;
+ fail:
+  return -1;
 }
 
 
@@ -203,6 +205,7 @@ size_t client_marshal(const client_t* restrict this, char* restrict data)
 size_t client_unmarshal(client_t* restrict this, char* restrict data)
 {
   size_t i, n, rc = sizeof(ssize_t) + 3 * sizeof(int) + sizeof(uint64_t) + 5 * sizeof(size_t);
+  int saved_errno, stage = 0;
   this->interception_conditions = NULL;
   this->multicasts = NULL;
   this->send_pending = NULL;
@@ -218,40 +221,37 @@ size_t client_unmarshal(client_t* restrict this, char* restrict data)
   buf_get_next(data, uint64_t, this->id);
   buf_get_next(data, size_t, n);
   if (n > 0)
-    if (mds_message_unmarshal(&(this->message), data))
-      return 0;
+    fail_if (mds_message_unmarshal(&(this->message), data));
+  stage++;
   data += n / sizeof(char);
   rc += n;
   buf_get_next(data, size_t, this->interception_conditions_count);
-  if (xmalloc(this->interception_conditions, this->interception_conditions_count, interception_condition_t))
-    goto fail;
+  fail_if (xmalloc(this->interception_conditions,
+		   this->interception_conditions_count, interception_condition_t));
   for (i = 0; i < this->interception_conditions_count; i++)
     {
       n = interception_condition_unmarshal(this->interception_conditions + i, data);
       if (n == 0)
 	{
 	  this->interception_conditions_count = i - 1;
-	  goto fail;
+	  fail_if (1);
 	}
       data += n / sizeof(char);
       rc += n;
     }
   buf_get_next(data, size_t, n);
-  if (xmalloc(this->multicasts, n, multicast_t))
-    goto fail;
+  fail_if (xmalloc(this->multicasts, n, multicast_t));
   for (i = 0; i < n; i++, this->multicasts_count++)
     {
       size_t m = multicast_unmarshal(this->multicasts + i, data);
-      if (m == 0)
-	goto fail;
+      fail_if (m == 0);
       data += m / sizeof(char);
       rc += m;
     }
   buf_get_next(data, size_t, this->send_pending_size);
   if (this->send_pending_size > 0)
     {
-      if (xmalloc(this->send_pending, this->send_pending_size, char))
-	goto fail;
+      fail_if (xmalloc(this->send_pending, this->send_pending_size, char));
       memcpy(this->send_pending, data, this->send_pending_size * sizeof(char));
       data += this->send_pending_size;
       rc += this->send_pending_size * sizeof(char);
@@ -265,6 +265,9 @@ size_t client_unmarshal(client_t* restrict this, char* restrict data)
   return rc;
   
  fail:
+  saved_errno = errno;
+  if (stage == 0)
+    goto done_failing;
   mds_message_destroy(&(this->message));
   for (i = 0; i < this->interception_conditions_count; i++)
     free(this->interception_conditions[i].condition);
@@ -278,7 +281,8 @@ size_t client_unmarshal(client_t* restrict this, char* restrict data)
       mds_message_destroy(this->modify_message);
       free(this->modify_message);
     }
-  return 0;
+ done_failing:
+  return errno = saved_errno, (size_t)0;
 }
 
 /**
diff --git a/src/mds-server/interception-condition.c b/src/mds-server/interception-condition.c
index 31905c9..cfe5d0c 100644
--- a/src/mds-server/interception-condition.c
+++ b/src/mds-server/interception-condition.c
@@ -71,10 +71,11 @@ size_t interception_condition_unmarshal(interception_condition_t* restrict this,
   buf_get_next(data, int64_t, this->priority);
   buf_get_next(data, int, this->modifying);
   n = (strlen(data) + 1) * sizeof(char);
-  if ((this->condition = malloc(n)) == NULL)
-    return 0;
+  fail_if ((this->condition = malloc(n)) == NULL);
   memcpy(this->condition, data, n);
   return sizeof(size_t) + sizeof(int64_t) + 2 * sizeof(int) + n;
+ fail:
+  return 0;
 }
 
 
diff --git a/src/mds-server/interceptors.c b/src/mds-server/interceptors.c
index 6d798d9..8a24e33 100644
--- a/src/mds-server/interceptors.c
+++ b/src/mds-server/interceptors.c
@@ -140,19 +140,10 @@ void add_intercept_condition(client_t* client, char* condition, int64_t priority
   else
     {
       /* Duplicate condition string. */
-      if ((condition = strdup(condition)) == NULL)
-	{
-	  xperror(*argv);
-	  return;
-	}
+      fail_if ((condition = strdup(condition)) == NULL);
       
       /* Grow the interception condition list. */
-      if (xrealloc(conds, n + 1, interception_condition_t))
-	{
-	  xperror(*argv);
-	  free(condition);
-	  return;
-	}
+      fail_if (xrealloc(conds, n + 1, interception_condition_t));
       client->interception_conditions = conds; 
       /* Store condition. */
       client->interception_conditions_count++;
@@ -174,6 +165,12 @@ void add_intercept_condition(client_t* client, char* condition, int64_t priority
 	  conds[n] = temp;
 	}
     }
+  
+  return;
+ fail:
+  xperror(*argv);
+  free(condition);
+  return;
 }
 
 
@@ -220,9 +217,7 @@ int find_matching_condition(client_t* client, size_t* hashes, char** keys, char*
   interception_condition_t* conds = client->interception_conditions;
   size_t n = 0, i;
   
-  errno = pthread_mutex_lock(&(mutex));
-  if (errno)
-    return -1;
+  fail_if ((errno = pthread_mutex_lock(&(mutex))));
   
   /* Look for a matching condition. */
   if (client->open)
@@ -240,6 +235,8 @@ int find_matching_condition(client_t* client, size_t* hashes, char** keys, char*
   pthread_mutex_unlock(&(mutex));
   
   return i < n;
+ fail:
+  return -1;
 }
 
 
@@ -252,23 +249,22 @@ int find_matching_condition(client_t* client, size_t* hashes, char** keys, char*
  * @param   headers                  The header name–value pairs
  * @param   count                    The number of accepted patterns
  * @param   interceptions_count_out  Slot at where to store the number of found interceptors
- * @return                           The found interceptors, NULL on error
+ * @return                           The found interceptors, `NULL` on error
  */
 queued_interception_t* get_interceptors(client_t* sender, size_t* hashes, char** keys, char** headers,
 					size_t count, size_t* interceptions_count_out)
 {
   queued_interception_t* interceptions = NULL;
-  size_t interceptions_count = 0;
-  size_t n = 0;
+  size_t interceptions_count = 0, n = 0;
   ssize_t node;
+  int saved_errno;
   
   /* Count clients. */
   foreach_linked_list_node (client_list, node)
     n++;
   
   /* Allocate interceptor list. */
-  if (xmalloc(interceptions, n, queued_interception_t))
-    return NULL;
+  fail_if (xmalloc(interceptions, n, queued_interception_t));
   
   /* Search clients. */
   foreach_linked_list_node (client_list, node)
@@ -280,11 +276,7 @@ queued_interception_t* get_interceptors(client_t* sender, size_t* hashes, char**
 	{
 	  int r = find_matching_condition(client, hashes, keys, headers, count,
 					  interceptions + interceptions_count);
-	  if (r == -1)
-	    {
-	      free(interceptions);
-	      return NULL;
-	    }
+	  fail_if (r == -1);
 	  if (r)
 	    /* List client of there was a matching condition. */
 	    interceptions_count++;
@@ -293,5 +285,10 @@ queued_interception_t* get_interceptors(client_t* sender, size_t* hashes, char**
   
   *interceptions_count_out = interceptions_count;
   return interceptions;
+  
+ fail:
+  saved_errno = errno;
+  free(interceptions);
+  return errno = saved_errno, NULL;
 }
 
diff --git a/src/mds-server/interceptors.h b/src/mds-server/interceptors.h
index 7bb60e5..e2e6041 100644
--- a/src/mds-server/interceptors.h
+++ b/src/mds-server/interceptors.h
@@ -77,7 +77,7 @@ int find_matching_condition(client_t* client, size_t* hashes, char** keys, char*
  * @param   headers                  The header name–value pairs
  * @param   count                    The number of accepted patterns
  * @param   interceptions_count_out  Slot at where to store the number of found interceptors
- * @return                           The found interceptors, NULL on error
+ * @return                           The found interceptors, `NULL` on error
  */
 queued_interception_t* get_interceptors(client_t* sender, size_t* hashes, char** keys, char** headers,
 					size_t count, size_t* interceptions_count_out);
diff --git a/src/mds-server/mds-server.c b/src/mds-server/mds-server.c
index 58eec60..fabdffa 100644
--- a/src/mds-server/mds-server.c
+++ b/src/mds-server/mds-server.c
@@ -130,8 +130,7 @@ int preinitialise_server(void)
 	  close_files((fd > 2) || (fd == socket_fd));
 	  
 	  /* Run mdsinitrc. */
-	  run_initrc(unparsed_args);
-	  return 1;
+	  run_initrc(unparsed_args); /* Does not return. */
 	}
     }
   
@@ -148,7 +147,7 @@ int preinitialise_server(void)
   
   return 0;
   
- pfail:
+ fail:
   xperror(*argv);
   return 1;
 }
@@ -302,7 +301,7 @@ void* slave_loop(void* data)
       if ((r == 0) && message_received(information))
 	goto terminate;
       else if (r == -2)
-	goto fail;
+	goto done;
       else if (r && (errno == EINTR) && terminating)
       	goto terminate; /* Stop the thread if we are re-exec:ing or terminating the server. */
     }
@@ -329,7 +328,7 @@ void* slave_loop(void* data)
   if (reexecing)
     goto reexec;
   
- fail: /* This done on success as well. */
+ done:
   /* Close socket and free resources. */
   close(slave_fd);
   free(msgbuf);
@@ -348,9 +347,9 @@ void* slave_loop(void* data)
   return NULL;
   
   
- pfail:
+ fail:
   xperror(*argv);
-  goto fail;
+  goto done;
   
   
  reexec:
@@ -403,15 +402,13 @@ void queue_message_multicast(char* message, size_t length, client_t* sender)
   uint64_t modify_id;
   char modify_id_header[13 + 3 * sizeof(uint64_t)];
   void* new_buf;
+  int saved_errno;
   
   /* Count the number of headers. */
   for (i = 0; i < n; i++)
     if (message[i] == '\n')
-      {
-	header_count++;
-	if (message[i + 1] == '\n')
-	  break;
-      }
+      if (header_count++, message[i + 1] == '\n')
+	break;
   
   if (header_count == 0)
     return; /* Invalid message. */
@@ -435,14 +432,14 @@ void queue_message_multicast(char* message, size_t length, client_t* sender)
       if ((header_values[i] = strdup(msg)) == NULL)
 	{
 	  header_count = i;
-	  goto pfail;
+	  fail_if (1);
 	}
       *colon = '\0';
       if ((headers[i] = strdup(msg)) == NULL)
 	{
-	  free(headers[i]);
+	  saved_errno = errno, free(headers[i]), errno = saved_errno;
 	  header_count = i;
-	  goto pfail;
+	  fail_if (1);
 	}
       *colon = ':';
       *end = '\n';
@@ -482,22 +479,22 @@ void queue_message_multicast(char* message, size_t length, client_t* sender)
   multicast->message_prefix = n;
   message = NULL;
   
+#define fail  fail_in_mutex
   /* Queue message multicasting. */
   with_mutex (sender->mutex,
 	      new_buf = sender->multicasts;
-	      if (xrealloc(new_buf, sender->multicasts_count + 1, multicast_t))
-		{
-		  xperror(*argv);
-		  goto fail_queue;
-		}
+	      fail_if (xrealloc(new_buf, sender->multicasts_count + 1, multicast_t));
 	      sender->multicasts = new_buf;
 	      sender->multicasts[sender->multicasts_count++] = *multicast;
 	      free(multicast);
 	      multicast = NULL;
-	     fail_queue:
+	      errno = 0;
+	     fail_in_mutex:
+	      xperror(*argv);
 	      );
+#undef fail
   
- fail: /* This is done before this function returns even if there was no error. */
+ done:
   /* Release resources. */
   xfree(headers, header_count);
   xfree(header_values, header_count);
@@ -508,9 +505,9 @@ void queue_message_multicast(char* message, size_t length, client_t* sender)
   free(multicast);
   return;
   
- pfail:
+ fail:
   xperror(*argv);
-  goto fail;
+  goto done;
 }
 
 
@@ -582,5 +579,7 @@ void run_initrc(char** args)
   
   /* Everything failed. */
   eprintf("unable to run %s file, you might as well kill me.", INITRC_FILE);
+  /* (‘me’ actually refers to the parant, whence it will to be coming.) */
+  exit(0);
 }
 
diff --git a/src/mds-server/mds-server.h b/src/mds-server/mds-server.h
index 4d6c5e7..4624761 100644
--- a/src/mds-server/mds-server.h
+++ b/src/mds-server/mds-server.h
@@ -53,7 +53,7 @@ void queue_message_multicast(char* message, size_t length, client_t* sender);
  * 
  * @param  args  The arguments to the child process
  */
-void run_initrc(char** args);
+void run_initrc(char** args) __attribute__((noreturn));
 
 
 #endif
diff --git a/src/mds-server/multicast.c b/src/mds-server/multicast.c
index 7a0b309..c3d09bc 100644
--- a/src/mds-server/multicast.c
+++ b/src/mds-server/multicast.c
@@ -124,8 +124,7 @@ size_t multicast_unmarshal(multicast_t* restrict this, char* restrict data)
   buf_get_next(data, size_t, this->message_ptr);
   buf_get_next(data, size_t, this->message_prefix);
   if (this->interceptions_count > 0)
-    if (xmalloc(this->interceptions, this->interceptions_count, queued_interception_t))
-      return 0;
+    fail_if (xmalloc(this->interceptions, this->interceptions_count, queued_interception_t));
   for (i = 0; i < this->interceptions_count; i++)
     {
       n = queued_interception_unmarshal(this->interceptions + i, data);
@@ -134,12 +133,13 @@ size_t multicast_unmarshal(multicast_t* restrict this, char* restrict data)
     }
   if (this->message_length > 0)
     {
-      if (xmalloc(this->message, this->message_length, char))
-	return 0;
+      fail_if (xmalloc(this->message, this->message_length, char));
       memcpy(this->message, data, this->message_length * sizeof(char));
       rc += this->message_length * sizeof(char);
     }
   return rc;
+ fail:
+  return 0;
 }
 
 
diff --git a/src/mds-server/receiving.c b/src/mds-server/receiving.c
index 15ebb4d..8571944 100644
--- a/src/mds-server/receiving.c
+++ b/src/mds-server/receiving.c
@@ -93,7 +93,7 @@ static int modifying_notify(client_t* client, mds_message_t message, uint64_t mo
   return 0;
   
   
- pfail:
+ fail:
   xperror(*argv);
   if (multicast != NULL)
     {
@@ -116,14 +116,13 @@ static int modifying_notify(client_t* client, mds_message_t message, uint64_t mo
  */
 static int add_intercept_conditions_from_message(client_t* client, int modifying, int64_t priority, int stop)
 {
-  int errno_ = 0;
+  int saved_errno;
   char* payload = client->message.payload;
   size_t payload_size = client->message.payload_size;
   size_t size = 64;
   char* buf;
   
-  if (xmalloc(buf, size + 1, char))
-    return -1;
+  fail_if (xmalloc(buf, size + 1, char));
   
   /* All messages */
   if (client->message.payload_size == 0)
@@ -149,10 +148,10 @@ static int add_intercept_conditions_from_message(client_t* client, int modifying
 	  char* old_buf = buf;
 	  if (xrealloc(buf, (size <<= 1) + 1, char))
 	    {
-	      errno_ = errno;
+	      saved_errno = errno;
 	      free(old_buf);
 	      pthread_mutex_unlock(&(client->mutex));
-	      break;
+	      fail_if (errno = saved_errno, 1);
 	    }
 	}
       memcpy(buf, payload, len);
@@ -166,8 +165,9 @@ static int add_intercept_conditions_from_message(client_t* client, int modifying
   
  done:
   free(buf);
-  errno = errno_;
-  return errno_ ? -1 : 0;
+  return 0;
+ fail:
+  return -1;
 }
 
 
@@ -183,6 +183,7 @@ static int assign_and_send_id(client_t* client, const char* message_id)
   char* msgbuf = NULL;
   char* msgbuf_;
   size_t n;
+  int rc = -1;
   
   /* Construct response. */
   n = 2 * 10 + strlen(message_id) + 1;
@@ -204,6 +205,7 @@ static int assign_and_send_id(client_t* client, const char* message_id)
   
   /* Queue message to be sent when this function returns.
      This done to simplify `multicast_message` for re-exec and termination. */
+#define fail  fail_in_mutex
   with_mutex (client->mutex,
 	      if (client->send_pending_size == 0)
 		{
@@ -216,20 +218,20 @@ static int assign_and_send_id(client_t* client, const char* message_id)
 		  /* Concatenate message to already pending messages. */
 		  size_t new_len = client->send_pending_size + n;
 		  char* msg_new = client->send_pending;
-		  if (xrealloc(msg_new, new_len, char))
-		    goto fail;
+		  fail_if (xrealloc(msg_new, new_len, char));
 		  memcpy(msg_new + client->send_pending_size, msgbuf, n * sizeof(char));
 		  client->send_pending = msg_new;
 		  client->send_pending_size = new_len;
 		}
-	      fail:
+	      (msgbuf = NULL, rc = 0, errno = 0);
+	     fail_in_mutex:
 	      );
+#undef fail
   
-  return 0;
-  
- pfail:
+ fail: /* Also success. */
+  xperror(*argv);
   free(msgbuf);
-  return -1;
+  return rc;
 }
 
 
@@ -327,7 +329,7 @@ int message_received(client_t* client)
   
   return 0;
   
- pfail:
+ fail:
   xperror(*argv);
   free(msgbuf);
   return 0;
diff --git a/src/mds-server/reexec.c b/src/mds-server/reexec.c
index 981569e..fe8c196 100644
--- a/src/mds-server/reexec.c
+++ b/src/mds-server/reexec.c
@@ -179,15 +179,13 @@ int unmarshal_server(char* state_buf)
   ssize_t node;
   pthread_t slave_thread;
   
-  
+#define fail  soft_fail
+
   /* Create memory address remapping table. */
-  if (hash_table_create(&unmarshal_remap_map))
-    {
-      xperror(*argv);
-      hash_table_destroy(&unmarshal_remap_map, NULL, NULL);
-      return -1;
-    }
-  
+  fail_if (hash_table_create(&unmarshal_remap_map));
+
+#undef fail
+#define fail  clients_fail
   
   /* Get the marshal protocal version. Not needed, there is only the one version right now. */
   /* buf_get(state_buf, int, 0, MDS_SERVER_VARS_VERSION); */
@@ -210,20 +208,16 @@ int unmarshal_server(char* state_buf)
       client_t* value;
       
       /* Allocate the client's information. */
-      if (xmalloc(value, 1, client_t))
-	goto clients_fail;
+      fail_if (xmalloc(value, 1, client_t));
       
       /* Unmarshal the address, it is used the the client list and the client map, that are also marshalled. */
       buf_get_next(state_buf, size_t, value_address);
       /* Unmarshal the client information. */
-      n = client_unmarshal(value, state_buf);
-      if (n == 0)
-	goto clients_fail;
+      fail_if (n = client_unmarshal(value, state_buf), n == 0);
       
       /* Populate the remapping table. */
       if (hash_table_put(&unmarshal_remap_map, value_address, (size_t)(void*)value) == 0)
-	if (errno)
-	  goto clients_fail;
+	fail_if (errno);
       
       /* Delayed seeking. */
       state_buf += n / sizeof(char);
@@ -247,14 +241,15 @@ int unmarshal_server(char* state_buf)
       break;
     }
   
+#undef fail
+#define fail  critical_fail
+  
   /* Unmarshal the client list. */
-  if (linked_list_unmarshal(&client_list, state_buf))
-    goto critical_fail;
+  fail_if (linked_list_unmarshal(&client_list, state_buf));
   state_buf += list_size / sizeof(char);
   
   /* Unmarshal the client map. */
-  if (fd_table_unmarshal(&client_map, state_buf, unmarshal_remapper))
-    goto critical_fail;
+  fail_if (fd_table_unmarshal(&client_map, state_buf, unmarshal_remapper));
   
   /* Remove non-found elements from the fd table. */
 #define __bit(I, _OP_)  client_map.used[I / 64] _OP_ ((uint64_t)1 << (I % 64))
@@ -291,8 +286,12 @@ int unmarshal_server(char* state_buf)
   hash_table_destroy(&unmarshal_remap_map, NULL, NULL);
   
   return with_error;
+#undef fail
   
-  
+ soft_fail:
+  xperror(*argv);
+  hash_table_destroy(&unmarshal_remap_map, NULL, NULL);
+  return -1;
  critical_fail:
   xperror(*argv);
   abort();
diff --git a/src/mds-server/slavery.c b/src/mds-server/slavery.c
index df6d552..088b6af 100644
--- a/src/mds-server/slavery.c
+++ b/src/mds-server/slavery.c
@@ -47,11 +47,15 @@ void* slave_loop(void*);
 int fetch_message(client_t* client)
 {
   int r = mds_message_read(&(client->message), client->socket_fd);
+  
   if (r == 0)
     return 0;
   
   if (r == -2)
-    eprint("corrupt message received.");
+    {
+      eprint("corrupt message received.");
+      fail_if (1);
+    }
   else if (errno == ECONNRESET)
     {
       r = mds_message_read(&(client->message), client->socket_fd);
@@ -60,11 +64,14 @@ int fetch_message(client_t* client)
     }
   else if (errno != EINTR)
     {
-      r = -2;
       xperror(*argv);
+      fail_if (1);
     }
   
+  fail_if (r == -2);
   return r;
+ fail:
+  return -2;
 }
 
 
@@ -81,14 +88,16 @@ int create_slave(pthread_t* thread_slot, int slave_fd)
     {
       xperror(*argv);
       with_mutex (slave_mutex, running_slaves--;);
-      return -1;
+      fail_if (1);
     }
   if ((errno = pthread_detach(*thread_slot)))
     {
       xperror(*argv);
-      return -1;
+      fail_if (1);
     }
   return 0;
+ fail:
+  return -1;
 }
 
 
@@ -96,14 +105,13 @@ int create_slave(pthread_t* thread_slot, int slave_fd)
  * Initialise a client, except for threading
  * 
  * @param   client_fd  The file descriptor of the client's socket
- * @return             The client information, NULL on error
+ * @return             The client information, `NULL` on error
  */
 client_t* initialise_client(int client_fd)
 {
   ssize_t entry = LINKED_LIST_UNUSED;
-  int locked = 0;
   client_t* information;
-  int errno_;
+  int locked = 0, saved_errno;
   size_t tmp;
   
   /* Create information table. */
@@ -131,14 +139,13 @@ client_t* initialise_client(int client_fd)
   return information;
   
   
- pfail:
-  errno_ = errno;
+ fail:
+  saved_errno = errno;
   if (locked)
     pthread_mutex_unlock(&slave_mutex);
   free(information);
   if (entry != LINKED_LIST_UNUSED)
     with_mutex (slave_mutex, linked_list_remove(&client_list, entry););
-  errno = errno_;
-  return NULL;
+  return errno = saved_errno, NULL;
 }
 
diff --git a/src/mds-server/slavery.h b/src/mds-server/slavery.h
index 92144fd..00f6084 100644
--- a/src/mds-server/slavery.h
+++ b/src/mds-server/slavery.h
@@ -45,7 +45,7 @@ int create_slave(pthread_t* thread_slot, int slave_fd);
  * Initialise a client, except for threading
  * 
  * @param   client_fd  The file descriptor of the client's socket
- * @return             The client information, NULL on error
+ * @return             The client information, `NULL` on error
  */
 client_t* initialise_client(int client_fd);