make this configurable

TODO.md

@@ -8,7 +8,7 @@ Goal: "aws cli works reliably for CreateTable/ListTables/PutItem/GetItem/DeleteI
 
 ### 1) HTTP + routing hardening
 - [ ] Audit request parsing boundaries:
-  - Max body size enforcement (config exists, need to verify enforcement path)
+  - Max body size enforcement — **DONE**
   - Missing/invalid headers → correct DynamoDB error types
   - Content-Type handling (be permissive but consistent)
 - [x] Ensure **all request-scoped allocations** come from the request arena (no accidental long-lived allocs)

main.odin

@@ -13,6 +13,13 @@ Config :: struct {
 	port:     int,
 	data_dir: string,
 	verbose:  bool,
+
+	// HTTP server config
+	max_body_size:              int,
+	max_headers:                int,
+	read_buffer_size:           int,
+	enable_keep_alive:          bool,
+	max_requests_per_connection: int,
 }
 
 main :: proc() {
@@ -36,8 +43,14 @@ main :: proc() {
 	fmt.printfln("Storage engine initialized at %s", config.data_dir)
 	fmt.printfln("Starting DynamoDB-compatible server on %s:%d", config.host, config.port)
 
-	// Create HTTP server
-	server_config := default_server_config()
+	// Create HTTP server with config values
+	server_config := Server_Config{
+		max_body_size              = config.max_body_size,
+		max_headers                = config.max_headers,
+		read_buffer_size           = config.read_buffer_size,
+		enable_keep_alive          = config.enable_keep_alive,
+		max_requests_per_connection = config.max_requests_per_connection,
+	}
 
 	server, server_ok := server_init(
 		context.allocator,
@@ -2015,14 +2028,20 @@ make_error_response :: proc(response: ^HTTP_Response, err_type: dynamodb.DynamoD
 
 parse_config :: proc() -> Config {
 	config := Config{
-		host = "0.0.0.0",
-		port = 8002,
-		data_dir = "./data",
-		verbose = false,
+		// Defaults
+		host                       = "0.0.0.0",
+		port                       = 8002,
+		data_dir                   = "./data",
+		verbose                    = false,
+		max_body_size              = 100 * 1024 * 1024, // 100 MB
+		max_headers                = 100,
+		read_buffer_size           = 8 * 1024,          // 8 KB
+		enable_keep_alive          = true,
+		max_requests_per_connection = 1000,
 	}
 
-	// Environment variables
-	if port_str, env_ok := os.lookup_env("JORMUN_PORT"); env_ok {
+	// Environment variables (lower priority)
+	if port_str, ok := os.lookup_env("JORMUN_PORT"); ok {
 		if port, parse_ok := strconv.parse_int(port_str); parse_ok {
 			config.port = port
 		}
@@ -2040,11 +2059,107 @@ parse_config :: proc() -> Config {
 		config.verbose = verbose == "1"
 	}
 
-	// TODO: Parse command line arguments
+	if max_body_str, ok := os.lookup_env("JORMUN_MAX_BODY_SIZE"); ok {
+		if max_body, parse_ok := strconv.parse_int(max_body_str); parse_ok {
+			config.max_body_size = max_body
+		}
+	}
+
+	// Command line arguments (highest priority)
+	args := os.args[1:] // Skip program name
+
+	for i := 0; i < len(args); i += 1 {
+		arg := args[i]
+
+		// Helper to get next arg value
+		get_value :: proc(args: []string, i: ^int) -> (string, bool) {
+			if i^ + 1 < len(args) {
+				i^ += 1
+				return args[i^], true
+			}
+			return "", false
+		}
+
+		switch arg {
+		case "--host", "-h":
+			if value, ok := get_value(args, &i); ok {
+				config.host = value
+			}
+		case "--port", "-p":
+			if value, ok := get_value(args, &i); ok {
+				if port, parse_ok := strconv.parse_int(value); parse_ok {
+					config.port = port
+				}
+			}
+		case "--data-dir", "-d":
+			if value, ok := get_value(args, &i); ok {
+				config.data_dir = value
+			}
+		case "--verbose", "-v":
+			config.verbose = true
+		case "--max-body-size":
+			if value, ok := get_value(args, &i); ok {
+				if size, parse_ok := strconv.parse_int(value); parse_ok {
+					config.max_body_size = size
+				}
+			}
+		case "--max-headers":
+			if value, ok := get_value(args, &i); ok {
+				if count, parse_ok := strconv.parse_int(value); parse_ok {
+					config.max_headers = count
+				}
+			}
+		case "--no-keep-alive":
+			config.enable_keep_alive = false
+		case "--help":
+			print_help()
+			os.exit(0)
+		}
+	}
 
 	return config
 }
 
+print_help :: proc() {
+	help_text := `
+JormunDB - DynamoDB-Compatible Database Server
+
+USAGE:
+    jormundb [OPTIONS]
+
+OPTIONS:
+    --host, -h <HOST>           Server bind address (default: 0.0.0.0)
+    --port, -p <PORT>           Server port (default: 8002)
+    --data-dir, -d <DIR>        Data directory path (default: ./data)
+    --verbose, -v               Enable verbose logging
+    --max-body-size <BYTES>     Maximum request body size in bytes (default: 104857600 = 100MB)
+    --max-headers <COUNT>       Maximum number of headers per request (default: 100)
+    --no-keep-alive             Disable HTTP keep-alive connections
+    --help                      Show this help message
+
+ENVIRONMENT VARIABLES:
+    JORMUN_HOST                 Same as --host
+    JORMUN_PORT                 Same as --port
+    JORMUN_DATA_DIR             Same as --data-dir
+    JORMUN_VERBOSE              Set to "1" to enable verbose mode
+    JORMUN_MAX_BODY_SIZE        Same as --max-body-size
+
+EXAMPLES:
+    # Start with default settings
+    jormundb
+
+    # Custom port and data directory
+    jormundb --port 9000 --data-dir /var/lib/jormundb
+
+    # Limit body size to 10MB
+    jormundb --max-body-size 10485760
+
+    # Use environment variables
+    JORMUN_PORT=9000 JORMUN_HOST=127.0.0.1 jormundb
+`
+	fmt.println(help_text)
+}
+
 print_banner :: proc(config: Config) {
 	banner := `
   ╔═══════════════════════════════════════════════╗