From 6cda2e8db548ff7c023f33f43e0a7e9773cb1714 Mon Sep 17 00:00:00 2001
From: lohhiiccc <96543753+lohhiiccc@users.noreply.github.com>
Date: Wed, 4 Feb 2026 23:09:36 +0100
Subject: [PATCH] refactor: standardize code style and improve clarity

---
 includes/internal/icmp_utils.h | 2 +-
 src/handle/create.c            | 2 +-
 src/packet/build.c             | 2 +-
 src/recv/api/process.c         | 5 +++--
 src/recv/core/receive_packet.c | 5 ++++-
 src/send/api/raw.c             | 8 ++++----
 6 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/includes/internal/icmp_utils.h b/includes/internal/icmp_utils.h
index 2162bbe..aa7f722 100644
--- a/includes/internal/icmp_utils.h
+++ b/includes/internal/icmp_utils.h
@@ -8,7 +8,7 @@
 /* Checksum calculation (RFC 1071) */
 uint16_t icmp_checksum(const void *data, size_t len);
 
-/* Time helpers - return 0 on success, -1 on error */
+/* Time helpers */
 int icmp_get_time(struct timespec *ts);
 int64_t icmp_time_diff_ns(const struct timespec *start,
                           const struct timespec *end);
diff --git a/src/handle/create.c b/src/handle/create.c
index 1bd27b7..a9ff241 100644
--- a/src/handle/create.c
+++ b/src/handle/create.c
@@ -25,7 +25,7 @@ icmp_create(void)
 		return NULL;
 	}
 
-	if ( -1 == socket_configure(h))
+	if (-1 == socket_configure(h))
 	{
 		close(h->fd);
 		free(h);
diff --git a/src/packet/build.c b/src/packet/build.c
index 43086ab..773ded8 100644
--- a/src/packet/build.c
+++ b/src/packet/build.c
@@ -24,7 +24,7 @@ icmp_build_packet(void *buffer, size_t buffer_len, uint8_t type, uint8_t code,
 
 	write_icmp_header(h, type, code, header_rest);
 	if (payload_len > 0)
-		memcpy((unsigned char*)buffer + sizeof(struct icmp_header), payload,
+		memcpy((uint8_t *)buffer + sizeof(struct icmp_header), payload,
 				payload_len);
 
 	h->checksum = htons(icmp_checksum(h, required_len));
diff --git a/src/recv/api/process.c b/src/recv/api/process.c
index 50a15ea..6eeda34 100644
--- a/src/recv/api/process.c
+++ b/src/recv/api/process.c
@@ -3,13 +3,14 @@
 #include "internal/icmp_recv.h"
 #include <stdint.h>
 
-#define MAX_PACKET_SIZE 1500
+/* Buffer for incoming packets: IP header + ICMP */
+#define RECV_BUFFER_SIZE 1500
 
 int
 icmp_process(icmp_handle_t *h, icmp_callback_t cb, void *userdata,
 			size_t max_packets)
 {
-	uint8_t buffer[MAX_PACKET_SIZE];
+	uint8_t buffer[RECV_BUFFER_SIZE];
 	struct sockaddr_in from;
 	ssize_t recv_len;
 	int processed;
diff --git a/src/recv/core/receive_packet.c b/src/recv/core/receive_packet.c
index dc6a510..159c6ac 100644
--- a/src/recv/core/receive_packet.c
+++ b/src/recv/core/receive_packet.c
@@ -15,6 +15,9 @@ recv_receive_packet(int fd, void *buffer, size_t buffer_len,
 	n = recvfrom(fd, buffer, buffer_len, 0, (struct sockaddr *)from,
 				&from_len);
 	if (n < 0)
-		return (EAGAIN == errno || EWOULDBLOCK == errno) ? 0 : -1;
+	{
+		int saved_errno = errno;
+		return (EAGAIN == saved_errno || EWOULDBLOCK == saved_errno) ? 0 : -1;
+	}
 	return n;
 }
diff --git a/src/send/api/raw.c b/src/send/api/raw.c
index 8123dc7..f65064a 100644
--- a/src/send/api/raw.c
+++ b/src/send/api/raw.c
@@ -4,9 +4,9 @@
 #include "internal/icmp_send.h"
 #include <stddef.h>
 
-/* Maximum payload size for simplicity */
-#define MAX_PAYLOAD_SIZE 1024
-#define MAX_PACKET_SIZE (8 + MAX_PAYLOAD_SIZE)
+/* MTU(1500) - IP header(20) - ICMP header(8) = 1472 */
+#define MAX_PAYLOAD_SIZE 1472
+#define ICMP_HEADER_SIZE 8
 
 /* Forward declarations */
 static int validate_payload(struct icmp_handle *h, const void *payload,
@@ -25,7 +25,7 @@ icmp_send_raw(icmp_handle_t *h, uint8_t type, uint8_t code,
 	if (0 == validate_payload(h, payload, len))
 		return -1;
 
-	uint8_t buffer[MAX_PACKET_SIZE];
+	uint8_t buffer[ICMP_HEADER_SIZE + MAX_PAYLOAD_SIZE];
 
 	int packet_len = icmp_build_packet(buffer, sizeof(buffer),
 			type, code, header_rest, payload, len);