add example http server

Author: robertmuth

BE/StdLib/syscall.a32.asm

@@ -379,3 +379,14 @@
     poparg res:S32
     pusharg res
     ret
+
+.fun shutdown NORMAL [S32] = [S32 U32]
+.bbl entry
+    poparg sockfd:S32
+    poparg how:U32
+    pusharg how
+    pusharg sockfd
+    syscall shutdown 293:U16
+    poparg res:S32
+    pusharg res
+    ret

BE/StdLib/syscall.a64.asm

@@ -376,3 +376,14 @@
     poparg res:S64
     pusharg res
     ret
+
+.fun shutdown NORMAL [S32] = [S32 U32]
+.bbl entry
+    poparg sockfd:S32
+    poparg how:U32
+    pusharg how
+    pusharg sockfd
+    syscall shutdown 210:U8
+    poparg res:S32
+    pusharg res
+    ret

BE/StdLib/syscall.x64.asm

@@ -379,3 +379,14 @@
     poparg res:S64
     pusharg res
     ret
+
+.fun shutdown NORMAL [S32] = [S32 U32]
+.bbl entry
+    poparg sockfd:S32
+    poparg how:U32
+    pusharg how
+    pusharg sockfd
+    syscall shutdown 48:U8
+    poparg res:S32
+    pusharg res
+    ret

FE/Lib/os.cw

@@ -277,6 +277,8 @@ pub global O_CLOEXEC   =  0x80000_u32
 {{extern}} {{cdecl}} pub fun recvfrom(fd s32, buf ^!u8, buflen uint, flags u32,
                                      src_addr uint, src_addrlen uint) sint:
 
+{{extern}} {{cdecl}} pub fun shutdown(fd s32, op u32) s32:
+
 
 pub fun FileWrite(fd FD, buffer span(u8)) union(uint, Error):
     let res = write(unwrap(fd), front(buffer), len(buffer))
@@ -568,3 +570,18 @@ pub fun SetSocketOptions(fd FD, level SocketLevel, option SocketOption, val span
     if res < 0:
         return wrap_as(res, Error)
     return void_val
+
+
+
+
+pub enum SHUT u32:
+    WR 0
+    RD 1
+    RDWR 2
+
+
+pub fun Shutdown(fd FD, how SHUT) union(void, Error):
+    let res = shutdown(unwrap(fd), unwrap(how))
+    if res < 0:
+        return wrap_as(res, Error)
+    return void_val

FE/TestData/http_server.cw

@@ -0,0 +1,61 @@
+module:
+
+import fmt
+import os
+
+global gPort = 8181_u16
+
+global gReply = "HTTP/1.1 200 OK\r\nContent-Type: text/plain\r\nContent-Length: 12\r\n\r\nHello World!";
+
+pub fun htons(x u16) u16:
+    return x << 8 | x >> 8
+
+
+macro make_blob# EXPR ($e EXPR) []:
+    make_span(bitwise_as(@$e, ^u8), size_of(type_of($e)))
+
+macro make_mut_blob# EXPR ($e EXPR) []:
+    make_span(bitwise_as(@$e, ^!u8), size_of(type_of($e)))
+
+fun main(argc s32, argv ^^u8) s32:
+    trylet server_fd os\FD = os\Socket(os\AddressFamily.INET, os\SocketType.STREAM, 0), err:
+        return 1
+
+    fmt\print#("Server fd: ",  unwrap(server_fd), "\n")
+    let! res void
+
+    ref let val = 1_u32
+    tryset res = os\SetSocketOptions(server_fd, os\SocketLevel.SOCKET, os\SocketOption.SO_REUSEADDR,
+                                  make_blob#(val)), err:
+        return 1
+
+    ref let addr = {os\SockAddrIn: os\AddressFamily.INET, htons(gPort), {[4]u8: 0, 0, 0, 0}}
+
+    tryset res = os\Bind(server_fd, make_blob#(addr)), err:
+        return 1
+
+    tryset res = os\Listen(server_fd, 3), err:
+        return 1
+
+    fmt\print#("Listening on port: ", gPort, "\n")
+
+    while true:
+        fmt\print#("Waiting for connection\n")
+        ref let addr os\SockAddrIn = undef
+        trylet client_fd os\FD = os\AcceptWithAddr(server_fd, make_mut_blob#(addr), 0), err:
+            return 1
+        trylet  n uint = os\SendTo(client_fd, gReply, 0), err:
+            return 1
+        trylet  n2 uint = os\SendTo(client_fd, "\r\n COOL\n\n\n", 0), err:
+            return 1
+        fmt\print#("Sent ", n, " bytes\n")
+        tryset res = os\Close(client_fd), err:
+            return 1
+
+    tryset res = os\Shutdown(server_fd, os\SHUT.RDWR), err:
+        return 1
+
+    tryset res = os\Close(server_fd), err:
+        return 1
+
+    return 0