Question

My server code is as follows:

while(bytes_written < filesize){
                    //Send from send_ptr
                    bw = send(child_socket, send_ptr, newLength, 0);
                    printf("%d bytes written\n", (int)bw);
                    //Increment bytes written
                    bytes_written += bw;
                    //Move send pointer
                    send_ptr = send_ptr + bw;
}

And my client code is as follows:

while((num_bytes_recv = read(sd, jpgBufferPointer, BUFFER_LENGTH))>0){
        total_bytes_recv += num_bytes_recv;
        printf("Read %d bytes\n",num_bytes_recv);

        //Check for error
        if(jpgError == NULL)
            jpgError = strstr(jpgBufferPointer, "404 Not Found");

        if(jpgError != NULL){
            //Forwarding error response
            if(send(sd, jpgBuffer, num_bytes_recv, 0) == -1){
                error("Failed to send response message to client"); 
            }
        }   
        else{
            //Find content size
            contentSizeBuffer = strstr(jpgBufferPointer,"Content-Length");

            if(contentSizeBuffer != NULL){
                contentSizeBuffer=contentSizeBuffer+16;
                contentSize=atoi(contentSizeBuffer);                    
                jpgBuffer=(char*)realloc(jpgBuffer,(contentSize+FILE_NAME_LENGTH*2)*sizeof(char));
                jpgBufferPointer=jpgBuffer;
            }
            jpgBufferPointer+=num_bytes_recv;
        }
    }

The server is saying it has sent all 43000 bytes, but client says it has received only 32768 bytes.

Appreciate any help! Thanks

Answer 1

You have a bug in the sending part, you should update newLength, because if you have 1 byte left to send from the file, it will send more, going out of the memory area where the content you want to send is stored. You should fix in this way:

bw = send(child_socket, send_ptr, newLength<(filesize-bytes_written)?newLength:(filesize-bytes_written), 0);

In this way the last send will have the correct size.

Also, use write instead of send if you are not using any flags.