echo server, multiple clients, lines <256 bytes

pollfds.s

@@ -0,0 +1,30 @@
+; edi - fd
+; si - events
+pollfds__append:
+    ; TODO check against pollfds_capacity
+    mov r10, [pollfds_len]
+    mov [pollfds + r10 * pollfd_size], edi
+    mov [pollfds + r10 * pollfd_size + 4], si
+    mov r11w, 0
+    mov [pollfds + r10 * pollfd_size + 6], r11w
+    add r10, 1
+    mov [pollfds_len], r10
+    ret
+
+; rdi - pollfds array index to remove
+pollfds__remove:
+    mov r11, [pollfds_len]
+    cmp rdi, r11
+    jge return  ; XXX index out of bounds, do some other error?
+    cmp r11, 1
+    jle pollfds__clear
+    mov r10, [pollfds + (r11 - 1) * pollfd_size]
+    mov [pollfds + rdi * pollfd_size], r10
+    sub r11, 1
+    mov [pollfds_len], r11
+    ret
+
+pollfds__clear:
+    mov r10, 0
+    mov [pollfds_len], r10
+    ret