Refactor: simplify the server flow, remove threads and read packets in bulk

.gitignore

@@ -37,3 +37,4 @@ passwd_file
 .ccls
 .clangd
 .vscode
+.cache

CMakeLists.txt

@@ -10,6 +10,10 @@ add_definitions("-D_DEFAULT_SOURCE")
 find_package(OpenSSL REQUIRED)
 
 set(EXECUTABLE_OUTPUT_PATH ${CMAKE_BINARY_DIR})
+set(LIBRARY_OUTPUT_PATH ${CMAKE_BINARY_DIR}/lib)
+
+# Add include directories for headers
+include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include ${CMAKE_CURRENT_SOURCE_DIR}/lib)
 
 file(GLOB SOURCES src/*.c)
 file(GLOB TEST src/hashtable.c src/bst.c src/config.c src/list.c src/trie.c
@@ -44,8 +48,11 @@ else (APPLE)
     TARGET_LINK_LIBRARIES(sol pthread ssl crypto crypt)
     TARGET_LINK_LIBRARIES(sol_test pthread ssl crypto crypt)
 endif (APPLE)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wunused -Werror -pedantic \
-    -Wno-unused-result -std=c11 -O3")
+    # set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wunused -Werror -pedantic \
+    # -Wno-unused-result -std=c11 -O3")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wunused -Werror -pedantic \
+    -Wno-unused-result -std=c11 -ggdb -fsanitize=address \
+    -fsanitize=undefined -fno-omit-frame-pointer -pg")
 
 endif (DEBUG)
 

COPYING

@@ -1,6 +1,6 @@
 BSD 2-Clause License
 
-Copyright (c) 2023, Andrea Giacomo Baldan
+Copyright (c) 2025, Andrea Giacomo Baldan
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without

conf/sol.conf

@@ -6,7 +6,7 @@
 # is set, UNIX family socket will be used
 
 ip_address 127.0.0.1
-ip_port 8883
+ip_port 1883  # 8883 for MQTT over TLS (MQTT clients such as mosquitto will automatically add TLS)
 
 # unix_socket /tmp/sol.sock
 
@@ -30,11 +30,11 @@ tcp_backlog 128
 # Interval of time between one stats publish on $SOL topics and the subsequent
 stats_publish_interval 10s
 
-cafile certs/ca.crt
-certfile certs/alaptop.crt
-keyfile certs/alaptop.key
+# cafile certs/ca.crt
+# certfile certs/alaptop.crt
+# keyfile certs/alaptop.key
 
 # allow_anonymous false
 # password_file passwd_file
 
-tls_protocols tlsv1,tlsv1_1,tlsv1_2,tlsv1_3
+# tls_protocols tlsv1,tlsv1_1,tlsv1_2,tlsv1_3

include/arena.h

@@ -0,0 +1,56 @@
+#ifndef ARENA_H
+#define ARENA_H
+
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct pool_allocator {
+    void *(*alloc)(void *context);
+    void (*free)(void *context, void *ptr);
+    void *context;
+} Pool_Allocator;
+
+#define pool_alloc(a)   ((a)->alloc((a)->context))
+#define pool_free(a, p) ((a)->free((a)->context, p))
+
+void *arena_pool_alloc(void *context);
+void arena_pool_free(void *context, void *ptr);
+
+struct memorypool *memorypool_new(size_t, size_t);
+void memorypool_destroy(struct memorypool *);
+void *memorypool_alloc(struct memorypool *);
+void memorypool_free(struct memorypool *, void *);
+
+// Free list definition
+
+typedef struct Free_List_Header {
+    size_t block_size;
+    size_t padding;
+} Free_List_Header;
+
+typedef struct Free_List_Node {
+    struct Free_List_Node *next;
+    size_t block_size;
+} Free_List_Node;
+
+typedef struct Free_List {
+    void *data;
+    size_t size;
+    size_t used;
+    Free_List_Node *head;
+} Free_List;
+
+typedef struct arena_allocator {
+    void *(*alloc)(void *context, size_t size);
+    void (*free)(void *context, void *ptr);
+    void *context;
+} Arena_Allocator;
+
+#define arena_alloc(a, s) ((a)->alloc((a)->context, (s)))
+#define arena_free(a, p)  ((a)->free((a)->context, (p)))
+
+Free_List *free_list_new(size_t size);
+void *free_list_alloc(void *, size_t);
+void free_list_free(void *, void *);
+
+#endif

src/bst.h → include/bst.h

@@ -1,7 +1,7 @@
 /*
  * BSD 2-Clause License
  *
- * Copyright (c) 2023 Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025 Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -45,6 +45,6 @@ struct bst_node *bst_search(const struct bst_node *, unsigned char);
 
 struct bst_node *bst_delete(struct bst_node *, unsigned char);
 
-void bst_destroy(struct bst_node *, void (*free_fn)(struct bst_node *));
+void bst_free(struct bst_node *, void (*free_fn)(struct bst_node *));
 
 #endif

src/config.h → include/config.h

@@ -1,6 +1,6 @@
 /* BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025, Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:

include/darray.h

@@ -0,0 +1,26 @@
+#ifndef DARRAY_H
+#define DARRAY_H
+
+#include <assert.h>
+
+// Dynamic array helpers
+
+#define da_extend(da)                                                          \
+    do {                                                                       \
+        (da).capacity *= 2;                                                    \
+        (da).items = realloc((da).items, (da).capacity * sizeof(*(da).items)); \
+        if (!(da).items) {                                                     \
+            fprintf(stderr, "DA realloc failed");                              \
+            exit(EXIT_FAILURE);                                                \
+        }                                                                      \
+    } while (0)
+
+#define da_append(da, item)                                                    \
+    do {                                                                       \
+        assert((da));                                                          \
+        if ((da).length + 1 == (da).capacity)                                  \
+            da_extend((da));                                                   \
+        (da).items[(da).length++] = (item);                                    \
+    } while (0)
+
+#endif

src/ev.h → include/ev.h

@@ -1,6 +1,6 @@
 /* BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025, Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -50,23 +50,25 @@ enum ev_type {
 
 struct ev_ctx;
 
+typedef void (*ev_callback)(struct ev_ctx *, void *);
+
 /*
  * Event struture used as the main carrier of clients informations, it will be
  * tracked by an array in every context created
  */
 struct ev {
     int fd;
     int mask;
-    void *rdata; // opaque pointer for read callback args
-    void *wdata; // opaque pointer for write callback args
-    void (*rcallback)(struct ev_ctx *, void *); // read callback
-    void (*wcallback)(struct ev_ctx *, void *); // write callback
+    void *rdata;           // opaque pointer for read callback args
+    void *wdata;           // opaque pointer for write callback args
+    ev_callback rcallback; // read callback
+    ev_callback wcallback; // write callback
 };
 
 /*
  * Event loop context, carry the expected number of events to be monitored at
  * every cycle and an opaque pointer to the backend used as engine
- * (Select | Epoll | Kqueue).
+ * (Select | Epoll | Kqueue).ev
  * By now we stick with epoll and skip over select, cause as the current
  * threaded model employed by the server is not very friendly with select
  * Level-trigger default setting. But it would be quiet easy abstract over the
@@ -81,13 +83,13 @@ struct ev_ctx {
     int stop;
     int maxevents;
     unsigned long long fired_events;
-    struct ev *events_monitored;
+    struct ev *monitored;
     void *api; // opaque pointer to platform defined backends
 };
 
 int ev_init(struct ev_ctx *, int);
 
-void ev_destroy(struct ev_ctx *);
+void ev_free(struct ev_ctx *);
 
 /*
  * Poll an event context for events, accepts a timeout or block forever,
@@ -113,32 +115,29 @@ void ev_stop(struct ev_ctx *);
  * ev_fire_event just without an event to be carried. Useful to add simple
  * descritors like a listening socket o message queue FD.
  */
-int ev_watch_fd(struct ev_ctx *, int, int);
+int ev_watch(struct ev_ctx *, int, int);
 
 /*
  * Remove a FD from the loop, even tho a close syscall is sufficient to remove
  * the FD from the underlying backend such as EPOLL/SELECT, this call ensure
  * that any associated events is cleaned out an set to EV_NONE
  */
-int ev_del_fd(struct ev_ctx *, int);
+int ev_delete(struct ev_ctx *, int);
 
 /*
  * Register a new event, semantically it's equal to ev_register_event but
  * it's meant to be used when an FD is not already watched by the event loop.
  * It could be easily integrated in ev_fire_event call but I prefer maintain
  * the samantic separation of responsibilities.
  */
-int ev_register_event(struct ev_ctx *, int, int,
-                      void (*callback)(struct ev_ctx *, void *), void *);
+int ev_add_event(struct ev_ctx *, int, int, ev_callback, void *);
 
-int ev_register_cron(struct ev_ctx *, void (*callback)(struct ev_ctx *, void *),
-                     void *, long long, long long);
+int ev_add_cron(struct ev_ctx *, ev_callback, void *, long long, long long);
 
 /*
  * Register a new event for the next loop cycle to a FD. Equal to ev_watch_fd
  * but allow to carry an event object for the next cycle.
  */
-int ev_fire_event(struct ev_ctx *, int, int,
-                  void (*callback)(struct ev_ctx *, void *), void *);
+int ev_oneshot(struct ev_ctx *, int, int, ev_callback, void *);
 
 #endif

src/handlers.h → include/handlers.h

@@ -1,6 +1,6 @@
 /* BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025, Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -28,12 +28,13 @@
 #ifndef HANDLERS_H
 #define HANDLERS_H
 
-struct topic;
+typedef struct topic Topic;
 struct mqtt_packet;
-struct io_event;
+typedef struct connection_context Connection_Context;
+typedef struct arena_allocator Arena_Allocator;
 
-int publish_message(struct mqtt_packet *, const struct topic *);
+void publish_message(struct mqtt_packet *, const Topic *, Arena_Allocator *);
 
-int handle_command(unsigned, struct io_event *);
+int handle_command(Connection_Context *);
 
 #endif

src/iterator.h → include/iterator.h

@@ -1,7 +1,7 @@
 /*
  * BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025, Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -47,7 +47,7 @@ struct iterator {
 struct iterator *iter_new(void *, void (*next)(struct iterator *));
 void iter_init(struct iterator *, void *, void (*next)(struct iterator *));
 struct iterator *iter_next(struct iterator *);
-void iter_destroy(struct iterator *);
+void iter_free(struct iterator *);
 
 #define FOREACH(it) for (; it && it->ptr; it = iter_next(it))
 

src/list.h → include/list.h

@@ -1,6 +1,6 @@
 /* BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan
+ * Copyright (c) 2025, Andrea Giacomo Baldan
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -56,7 +56,7 @@ List *list_new(int (*destructor)(struct list_node *));
  * Release a list, accept a integer flag to control the depth of the free call
  * (e.g. going to free also data field of every node)
  */
-void list_destroy(List *, int);
+void list_free(List *, int);
 
 /* Return list size */
 unsigned long list_size(const List *);

src/logging.h → include/logging.h

@@ -1,6 +1,6 @@
 /* BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025, Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:

src/memory.h → include/memory.h

@@ -1,6 +1,6 @@
 /* BSD 2-Clause License
  *
- * Copyright (c) 2023, Andrea Giacomo Baldan All rights reserved.
+ * Copyright (c) 2025, Andrea Giacomo Baldan All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met: