From d54596514c30343305b7cc4b8be36c712d536e7a Mon Sep 17 00:00:00 2001
From: root <>
Date: Sun, 11 May 2025 08:22:07 +0000
Subject: [PATCH] echo then close connection

---
 main.s     | 54 +++++++++++++++++++++++++++++++++++++++++++++++-------
 readline.s | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 83 insertions(+), 7 deletions(-)
 create mode 100644 readline.s

diff --git a/main.s b/main.s
index 881a3d5..8905309 100644
--- a/main.s
+++ b/main.s
@@ -24,8 +24,10 @@ POLLIN          equ 1
 POLLOUT         equ 4
 SHUT_RDWR       equ 2
 
-pollfd_size equ 4 + 2 + 2  ; $ man 2 poll
-pollfds_capacity equ 100
+pollfd_size         equ 4 + 2 + 2  ; $ man 2 poll
+pollfds_capacity    equ 100
+client_size         equ 1 + 256 + 256  ; state, line buffer, uri
+clients_capacity    equ pollfds_capacity - 1
 
 SECTION .data
 server_path     db "server.sock", 0x00
@@ -33,15 +35,18 @@ server_path_len equ $ - server_path
 sockaddr_size   equ 2 + 108  ; $ man 7 unix
 goodbye         db "goodbye", 0x0a
 goodbye_len     equ $ - goodbye
+pollfds_len     dq 0
+clients_len     dq 0
 
 SECTION .bss
 sockaddr        resb sockaddr_size
 pollfds         resb pollfd_size * pollfds_capacity
-pollfds_len     resb 8
+clients         resb (4 + client_size) * clients_capacity
 
 SECTION .text
 
 %include "server.s"
+%include "readline.s"
 
 _start:
     call make_server
@@ -84,11 +89,27 @@ pollfds__scan__found__client:
     ; TODO check r10w, incl for POLLNVAL & POLLERR
     push rdi
 
+    mov rdi, r14
+    call clients__append
+
+    mov r12, [clients_len]
+    add r12, -1
+    imul r12, client_size
+    add r12, clients
+    add r12, 4
+
+    mov rdi, r14
+    mov rsi, r12
+    mov rdx, 256
+    call readline
+    cmp rax, 0  ; TODO
+    jl exit
+    ;push rax  ; TODO
+
+    mov rdx, rax
     mov rax, SYS_WRITE
-    mov rdi, 0
-    mov edi, r14d
-    mov rsi, goodbye
-    mov rdx, goodbye_len
+    mov rdi, r14
+    mov rsi, r12
     syscall
     cmp rax, 0
     jl exit  ; TODO handle this gracefully
@@ -132,6 +153,7 @@ pollfds__scan__found__server:
 ; 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
@@ -157,6 +179,24 @@ pollfds__clear:
     mov [pollfds_len], r10
     ret
 
+; esi - fd
+clients__append:
+    ; TODO check against client_capacity
+    mov r10, [clients_len]
+    imul r10, client_size
+    add r10, clients
+    mov [r10], esi
+    add r10, 4
+    mov r8b, 0
+    mov r11, 0
+
+clients__append__init:
+    cmp r11, client_size
+    jge return
+    mov [r10 + r11], r8b
+    add r11, 1
+    jmp clients__append__init
+
 return:
     ret
 
diff --git a/readline.s b/readline.s
new file mode 100644
index 0000000..aba4769
--- /dev/null
+++ b/readline.s
@@ -0,0 +1,36 @@
+; Returns length in rax
+; Errors (in rax):
+; -1024 - line too long
+; other negative - error from read(2)
+; Arguments:
+; rdi - fd
+; rsi - buffer
+; rdx - max length
+readline:
+    push rdi
+    push rsi
+    push rdx
+    mov rax, SYS_READ
+    syscall
+    pop rdx
+    pop rsi
+    pop rdi
+    cmp rax, 0
+    jl return
+    mov r10, 0
+
+readline__scan:
+    cmp r10, rax
+    jge readline__overflow
+    mov r11b, [rsi + r10]
+    add r10, 1
+    cmp r11b, 0x0a  ; '\n'
+    jne readline__scan
+
+readline__return:
+    mov rax, r10
+    ret
+
+readline__overflow:
+    mov rax, -1024
+    ret