ext/kgio/kgio_ext.c

   1 #include "kgio.h"
   2 #include <sys/utsname.h>
   3 #include <stdio.h>
   4 /* true if TCP Fast Open is usable */
   5 unsigned kgio_tfo;
   6 static VALUE eErrno_EPIPE, eErrno_ECONNRESET;
   7 static ID id_set_backtrace;
   8
   9 static void tfo_maybe(void)
  10 {
  11         VALUE mKgio = rb_define_module("Kgio");
  12
  13         /* Deal with the case where system headers have not caught up */
  14         if (KGIO_TFO_MAYBE) {
  15                 /* Ensure Linux 3.7 or later for TCP_FASTOPEN */
  16                 struct utsname buf;
  17                 unsigned maj, min;
  18
  19                 if (uname(&buf) != 0)
  20                         rb_sys_fail("uname");
  21                 if (sscanf(buf.release, "%u.%u", &maj, &min) != 2)
  22                         return;
  23                 if (maj < 3 || (maj == 3 && min < 7))
  24                         return;
  25         }
  26
  27         /*
  28          * KGIO_TFO_MAYBE will be false if a distro backports TFO
  29          * to a pre-3.7 kernel, but includes the necessary constants
  30          * in system headers
  31          */
  32 #if defined(MSG_FASTOPEN) && defined(TCP_FASTOPEN)
  33         rb_define_const(mKgio, "TCP_FASTOPEN", INT2NUM(TCP_FASTOPEN));
  34         rb_define_const(mKgio, "MSG_FASTOPEN", INT2NUM(MSG_FASTOPEN));
  35         kgio_tfo = 1;
  36 #endif
  37 }
  38
  39 void kgio_raise_empty_bt(VALUE err, const char *msg)
  40 {
  41         VALUE exc = rb_exc_new2(err, msg);
  42         VALUE bt = rb_ary_new();
  43
  44         rb_funcall(exc, id_set_backtrace, 1, bt);
  45         rb_exc_raise(exc);
  46 }
  47
  48 void kgio_wr_sys_fail(const char *msg)
  49 {
  50         switch (errno) {
  51         case EPIPE:
  52                 errno = 0;
  53                 kgio_raise_empty_bt(eErrno_EPIPE, msg);
  54         case ECONNRESET:
  55                 errno = 0;
  56                 kgio_raise_empty_bt(eErrno_ECONNRESET, msg);
  57         }
  58         rb_sys_fail(msg);
  59 }
  60
  61 void kgio_rd_sys_fail(const char *msg)
  62 {
  63         if (errno == ECONNRESET) {
  64                 errno = 0;
  65                 kgio_raise_empty_bt(eErrno_ECONNRESET, msg);
  66         }
  67         rb_sys_fail(msg);
  68 }
  69
  70 void Init_kgio_ext(void)
  71 {
  72         VALUE mKgio = rb_define_module("Kgio");
  73         VALUE mPipeMethods = rb_define_module_under(mKgio, "PipeMethods");
  74         VALUE mSocketMethods = rb_define_module_under(mKgio, "SocketMethods");
  75         VALUE mWaiters = rb_define_module_under(mKgio, "DefaultWaiters");
  76
  77         id_set_backtrace = rb_intern("set_backtrace");
  78         eErrno_EPIPE = rb_const_get(rb_mErrno, rb_intern("EPIPE"));
  79         eErrno_ECONNRESET = rb_const_get(rb_mErrno, rb_intern("ECONNRESET"));
  80
  81         /*
  82          * Returns the client IP address of the socket as a string
  83          * (e.g. "127.0.0.1" or "::1").
  84          * This is always the value of the Kgio::LOCALHOST constant
  85          * for UNIX domain sockets.
  86          */
  87         rb_define_attr(mSocketMethods, "kgio_addr", 1, 1);
  88         rb_include_module(mPipeMethods, mWaiters);
  89         rb_include_module(mSocketMethods, mWaiters);
  90
  91         tfo_maybe();
  92         init_kgio_wait();
  93         init_kgio_read();
  94         init_kgio_write();
  95         init_kgio_writev();
  96         init_kgio_connect();
  97         init_kgio_accept();
  98         init_kgio_poll();
  99         init_kgio_tryopen();
 100 }