feat: icmp_create_block()

README.md

@@ -1,7 +1,7 @@
 # libicmp
 
-Non-blocking ICMPv4 library for building ping, traceroute, and network
-diagnostic tools.
+ICMPv4 library for building ping, traceroute, and network diagnostic tools.
+Supports both non-blocking (default) and blocking socket modes.
 
 ## Dependencies
 
@@ -28,12 +28,14 @@ make test
 
 ```c
 icmp_handle_t *icmp_create(void);
+icmp_handle_t *icmp_create_block(void);
 void           icmp_destroy(icmp_handle_t *h);
 int            icmp_get_fd(const icmp_handle_t *h);
 ```
 
-`icmp_create()` opens a raw ICMP socket and returns an opaque handle.
-`icmp_get_fd()` exposes the underlying file descriptor for use with
+`icmp_create()` opens a raw ICMP socket in non-blocking mode and returns an
+opaque handle. `icmp_create_block()` does the same but leaves the socket in
+blocking mode`icmp_get_fd()` exposes the underlying file descriptor for use with
 `select()` or `poll()`. Errors are retrieved via `icmp_strerror()`.
 
 ### Send
@@ -71,12 +73,13 @@ on error.
 ## Modules
 
 ### handle/
-Handle lifecycle: `icmp_create()`, `icmp_destroy()`, `icmp_get_fd()`.
-Owns the opaque `icmp_handle_t` struct and the error state attached to it.
+Handle lifecycle: `icmp_create()`, `icmp_create_block()`, `icmp_destroy()`,
+`icmp_get_fd()`. Owns the opaque `icmp_handle_t` struct and the error state
+attached to it.
 
 ### socket/
-Raw socket creation, non-blocking configuration, and the DF (Don't
-Fragment) flag via `IP_MTU_DISCOVER`.
+Raw socket creation, optional non-blocking configuration (`O_NONBLOCK`), and
+the DF (Don't Fragment) flag via `IP_MTU_DISCOVER`.
 
 ### send/
 Packet building and transmission. Assembles the ICMP header and payload,

includes/icmp.h

@@ -50,6 +50,7 @@ typedef void (*icmp_callback_t)(const icmp_reply_t *reply, void *userdata);
 
 /* Handle lifecycle */
 icmp_handle_t *icmp_create(void);
+icmp_handle_t *icmp_create_block(void);
 void icmp_destroy(icmp_handle_t *h);
 int icmp_get_fd(const icmp_handle_t *h);
 

src/handle/create.c

@@ -8,10 +8,11 @@
 /* Forward declarations */
 static int alloc_icmp_handle(struct icmp_handle **h);
 static void init_icmp_handle(struct icmp_handle *h);
+static struct icmp_handle *create_handle(void);
 /* -------------------- */
 
-icmp_handle_t *
-icmp_create(void)
+static struct icmp_handle *
+create_handle(void)
 {
 	struct icmp_handle *h;
 
@@ -26,6 +27,17 @@ icmp_create(void)
 		return NULL;
 	}
 
+	return h;
+}
+
+icmp_handle_t *
+icmp_create(void)
+{
+	struct icmp_handle *h = create_handle();
+
+	if (NULL == h)
+		return NULL;
+
 	if (-1 == socket_configure(h))
 	{
 		close(h->fd);
@@ -36,6 +48,12 @@ icmp_create(void)
 	return (icmp_handle_t *)h;
 }
 
+icmp_handle_t *
+icmp_create_block(void)
+{
+	return (icmp_handle_t *)create_handle();
+}
+
 static int
 alloc_icmp_handle(struct icmp_handle **h)
 {