From 7ee30af4460f4a00a89f073a5a11b78649b16118 Mon Sep 17 00:00:00 2001
From: "Sergey Semyonov (Serge)" <ion2@mail.ru>
Date: Fri, 16 Jun 2017 07:53:37 +0000
Subject: [PATCH] kernel: read/write operations on pipe

git-svn-id: svn://kolibrios.org@6927 a494cfbc-eb01-0410-851d-a64ba20cac60
---
 kernel/trunk/posix/pipe.inc  | 79 ++++++++++++++++++++++++++++++------
 kernel/trunk/posix/posix.inc | 33 +++++++++++++--
 2 files changed, 96 insertions(+), 16 deletions(-)

diff --git a/kernel/trunk/posix/pipe.inc b/kernel/trunk/posix/pipe.inc
index 097085ce7e..37f094d2df 100644
--- a/kernel/trunk/posix/pipe.inc
+++ b/kernel/trunk/posix/pipe.inc
@@ -140,6 +140,8 @@ purge .intpipe
 align 4
 pipe_read:
         mov     edi, edx
+
+.again:
         lea     ecx, [ebp+PIPE.pipe_lock]
         call    mutex_lock
 
@@ -161,16 +163,15 @@ pipe_read:
         mov     [esp+SYSCALL_STACK._eax], ecx
         sub     [ebp+PIPE.count], ecx
         cld
-        rep stosb
+        rep movsb
         and     esi, 0xFFF
-        add     [ebp+PIPE.read_end], esi
+        mov     [ebp+PIPE.read_end], esi
 
         lea     ecx, [ebp+PIPE.pipe_lock]
         call    mutex_unlock
         ret
 
 .wait:
-
         sub     esp, sizeof.MUTEX_WAITER
         mov     ebx, [TASK_BASE]
         mov     [esp+MUTEX_WAITER.task], ebx
@@ -178,23 +179,15 @@ pipe_read:
 
         list_add_tail esp, edx      ;esp= new waiter, edx= list head
 
-.again:
         lea     ecx, [ebp+PIPE.pipe_lock]
         call    mutex_unlock
 
         mov     [ebx+TASKDATA.state], 1
         call    change_task
 
-        lea     ecx, [ebp+PIPE.pipe_lock]
-        call    mutex_lock
-
-        mov     ecx, [ebp+PIPE.count]
-        test    ecx, ecx
-        jz      .again
-
         list_del esp
         add     esp, sizeof.MUTEX_WAITER
-        jmp     .check_count
+        jmp     .again
 
 .eof:
         mov     [esp+SYSCALL_STACK._eax], eax
@@ -202,9 +195,69 @@ pipe_read:
         call    mutex_unlock
         ret
 
+; edx buf
+; esi count
+; ebp pipe
+
+align 4
+pipe_write:
+        mov     edi, edx
+
+.again:
+        lea     ecx, [ebp+PIPE.pipe_lock]
+        call    mutex_lock
+
+        xor     eax, eax
+        cmp     eax, [ebp+PIPE.readers]
+        je      .epipe
+
+        mov     ecx, [ebp+PIPE.count]
+        sub     ecx, 4096
+        jz      .wait
+
+.check_count:
+        cmp     ecx, esi
+        jb      .write
+        mov     ecx, esi
+.write:
+        mov     esi, [ebp+PIPE.buffer]
+        add     esi, [ebp+PIPE.write_end]
+        mov     [esp+SYSCALL_STACK._eax], ecx
+        add     [ebp+PIPE.count], ecx
+        cld
+        rep movsb
+        and     esi, 0xFFF
+        mov     [ebp+PIPE.write_end], esi
+
+        lea     ecx, [ebp+PIPE.pipe_lock]
+        call    mutex_unlock
+        ret
+
+.wait:
+        sub     esp, sizeof.MUTEX_WAITER
+        mov     ebx, [TASK_BASE]
+        mov     [esp+MUTEX_WAITER.task], ebx
+        lea     edx, [ebp+PIPE.wlist]
+
+        list_add_tail esp, edx      ;esp= new waiter, edx= list head
+
+        lea     ecx, [ebp+PIPE.pipe_lock]
+        call    mutex_unlock
+
+        mov     [ebx+TASKDATA.state], 1
+        call    change_task
+
+        list_del esp
+        add     esp, sizeof.MUTEX_WAITER
+        jmp     .again
+
+.epipe:
+        mov     [esp+SYSCALL_STACK._eax], -EPIPE
+        lea     ecx, [ebp+PIPE.pipe_lock]
+        call    mutex_unlock
+        ret
 
 align 4
 pipe_close:
-pipe_write:
         mov     [esp+SYSCALL_STACK._eax], -EBADF
         ret
diff --git a/kernel/trunk/posix/posix.inc b/kernel/trunk/posix/posix.inc
index 05d905b1f7..0dcd835cc0 100644
--- a/kernel/trunk/posix/posix.inc
+++ b/kernel/trunk/posix/posix.inc
@@ -13,7 +13,7 @@ EFAULT  equ     14
 ;EINVAL  equ     22      11   defined in stack.inc
 ENFILE  equ     23
 EMFILE  equ     24
-
+EPIPE   equ     32
 
 FILEOP_CLOSE    equ     0
 FILEOP_READ     equ     1
@@ -49,8 +49,8 @@ sys_posix_call:
         dd sys_futex        ;7     reserved
         dd sys_posix.fail   ;8     sys_open
         dd sys_posix.fail   ;9     sys_close
-        dd sys_posix.fail   ;10    sys_read
-        dd sys_posix.fail   ;11    sys_write
+        dd sys_read         ;10    read()
+        dd sys_write        ;11    write()
         dd sys_posix.fail   ;12    sys_dup3
         dd sys_pipe2        ;13
 .end:
@@ -95,3 +95,30 @@ sys_read:
         mov     [esp+SYSCALL_STACK._eax], -EBADF
         ret
 
+;ssize_t write(int fd, const void *buf, size_t count);
+; ecx fd
+; edx buf
+; esi count
+
+align 4
+sys_write:
+        cmp     ecx, STDERR_FILENO
+        jbe     .fail
+        cmp     ecx, (PROC.pdt_0 - PROC.htab)/4
+        jae     .fail
+
+        mov     edi, [current_process]
+        mov     ebp, [edi+PROC.htab+ecx*4]
+
+        cmp     [ebp+FILED.magic], 'PIPE'
+        jne     .fail
+        cmp     [ebp+FILED.handle], ecx
+        jne     .fail
+
+        mov     ebp, [ebp+FILED.file]
+        mov     eax, [ebp]
+        jmp     dword [eax+FILEOP_WRITE*4]
+.fail:
+        mov     [esp+SYSCALL_STACK._eax], -EBADF
+        ret
+