Merge pull request #17 from Black-Speedy/CheckSum

minor refactoring and added checksum

WebShare-Connect/client.c

@@ -1,10 +1,12 @@
 #include "WebShare-Connect.h"
 #include "client.h"
+#include "sha512.h"
 
 // This is the header for the file
 typedef struct {
     int64_t file_size;
-	int chunk_size;
+    int chunk_size;
+    unsigned char hash[SHA512_DIGEST_LENGTH];
 } file_header_t;
 
 zsock_t* client(void* context, const char *port, int threads)
@@ -25,23 +27,23 @@ zsock_t* client(void* context, const char *port, int threads)
 }
 
 void client_receive(zsock_t* client_sock, const char* output_file_path) {
-    printf("Receiving file...\n");
+    printf("\n-- File Reception --\n");
 
     file_header_t header;
     size_t header_size = sizeof(file_header_t);
     byte* header_buf = NULL;
 
-    // Receive the header as a binary blob
+    // Receive the header
     int rc = zsock_recv(client_sock, "b", &header_buf, &header_size);
     if (rc == -1) {
-        fprintf(stderr, "Failed to receive header\n");
+        fprintf(stderr, "Error: Failed to receive header.\n");
         return;
     }
 
-    // Ensure the received header size matches the expected size
+    // Validate the header size
     if (header_size != sizeof(file_header_t)) {
-        fprintf(stderr, "Received header size does not match\n");
-        free(header_buf); // Free the received buffer
+        fprintf(stderr, "Error: Received header size does not match expected size.\n");
+        free(header_buf);
         return;
     }
 
@@ -53,21 +55,21 @@ void client_receive(zsock_t* client_sock, const char* output_file_path) {
     memcpy(&header, header_buf, sizeof(header));
     free(header_buf); // Free the received buffer after copying
 
-    printf("Received file header\n");
     int64_t file_size = header.file_size;
     int chunk_size = header.chunk_size;
-    printf("Expected file size: %lld bytes\n", file_size);
-    printf("Chunk size: %d bytes\n", chunk_size);
+    printf("Header received successfully.\n");
+    printf("Expected file size: %lld bytes.\n", header.file_size);
+    printf("Chunk size: %d bytes.\n", header.chunk_size);
 
-    char* buffer = (char*)malloc(chunk_size);
-    if (buffer == NULL) {
-        fprintf(stderr, "Memory allocation error\n");
+    char* buffer = (char*)malloc(header.chunk_size);
+    if (!buffer) {
+        fprintf(stderr, "Error: Memory allocation failed.\n");
         return;
     }
 
     FILE* fp = fopen(output_file_path, "wb");
-    if (fp == NULL) {
-        fprintf(stderr, "File open error\n");
+    if (!fp) {
+        fprintf(stderr, "Error: File open failed.\n");
         free(buffer);
         return;
     }
@@ -93,13 +95,39 @@ void client_receive(zsock_t* client_sock, const char* output_file_path) {
         }
         received_size += size;
         current_chunk++;
-        fflush(&buffer);
-        //printf("Received chunk %d/%d with size %zu bytes\n", current_chunk, chunk_count, size);
+        printf("Chunk %d/%d received. Size: %d bytes.\n", current_chunk, chunk_count, size);
     }
-
     free(buffer);
     fclose(fp);
-    printf("File reception completed.\n");
+
+    // Compute hash of received file and compare with the expected hash
+    unsigned char* expected_hash = header.hash;
+    unsigned char received_hash[SHA512_DIGEST_LENGTH];
+    compute_sha512(output_file_path, received_hash); // Compute hash of received file
+    char received_hash_string[SHA512_DIGEST_LENGTH * 2 + 1];
+    char expected_hash_string[SHA512_DIGEST_LENGTH * 2 + 1];
+    convert_hash_to_hex_string(received_hash, received_hash_string, SHA512_DIGEST_LENGTH); // Convert received hash
+    convert_hash_to_hex_string(expected_hash, expected_hash_string, SHA512_DIGEST_LENGTH); // Convert expected hash
+
+    // Compare the raw binary hashes
+    if (memcmp(received_hash, expected_hash, SHA512_DIGEST_LENGTH) != 0) 
+    {
+        fprintf(stderr, "Received file hash does not match\n");
+        printf("Received Hash (binary): ");
+        for (int i = 0; i < SHA512_DIGEST_LENGTH; i++) 
+        {
+            printf("%02x", received_hash[i]);
+        }
+        printf("\nExpected Hash (binary): ");
+        for (int i = 0; i < SHA512_DIGEST_LENGTH; i++) 
+        {
+            printf("%02x", expected_hash[i]);
+        }
+        printf("\n");
+    }
+    else {
+        printf("File hash verified successfully.\n");
+    }
 }
 
 
@@ -125,7 +153,9 @@ int client_main(int argc, char const* argv[]) {
 
 	// Receive file
 	client_receive(client_sock, output_file_path);
-    printf("File received.\n");
+    printf("\x1b[32mFile transfer completed successfully.\x1b[32m\n ");
+    // return to normal color
+    printf("\x1b[0m");
 
 	// Clean up
 	zsock_destroy(&client_sock);