libphobos/libdruntime/core/sys/posix/sys/ioccom.d

   1 /**
   2  * D header file for POSIX.
   3  *
   4  * License: $(HTTP www.boost.org/LICENSE_1_0.txt, Boost License 1.0).
   5  */
   6
   7 module core.sys.posix.sys.ioccom;
   8
   9 version (Posix):
  10
  11 nothrow @nogc:
  12
  13 version (OSX)
  14 {
  15     /* OSX ioctl's (based on FreeBSD) encode the command in the lower 16-bits
  16      * and the size of any in/out parameters in the lower 13 bits of the upper
  17      * 16-bits of a 32 bit unsigned integer. The high 3 bits of the upper
  18      * 16-bits encode the in/out status of the parameter.
  19      */
  20     enum uint IOCPARM_MASK = 0x1fff; // parameter length, at most 13 bits
  21     uint IOCPARM_LEN(uint x) // to extract the encoded parameter length
  22     {
  23         return ((x >> 16) & IOCPARM_MASK);
  24     }
  25     uint IOCBASECMD(uint x) // to extract the encoded command
  26     {
  27         return (x & ~(IOCPARM_MASK << 16));
  28     }
  29     uint IOCGROUP(uint x) // to extract the encoded group
  30     {
  31         return ((x >> 8) & 0xff);
  32     }
  33
  34     enum uint IOCPARM_MAX = (IOCPARM_MASK + 1); // max size of ioctl args
  35
  36     enum uint IOC_VOID = 0x20000000; // no parameters
  37     enum uint IOC_OUT = 0x40000000; // copy parameters back
  38     enum uint IOC_IN = 0x80000000; // copy parameters into
  39     enum uint IOC_INOUT = (IOC_IN | IOC_OUT); // copy parameter into and get back
  40     enum uint IOC_DIRMASK = 0xe0000000; // mask to extract above direction parameters
  41
  42     // encode the ioctl info into 32 bits
  43     uint _IOC(T=typeof(null))(uint inorout, uint group, uint num, size_t len)
  44     {
  45         return (inorout | ((len & IOCPARM_MASK) << 16) | (group << 8) | num);
  46     }
  47
  48     // encode a command with no parameters
  49     uint _IO(char g, int n)
  50     {
  51         return _IOC(IOC_VOID, cast(uint)g, cast(uint)n, cast(size_t)0);
  52     }
  53     // encode a command that returns info
  54     uint _IOR(T)(char g, int n)
  55     {
  56         return _IOC!(T)(IOC_OUT, cast(uint)g, cast(uint)n, T.sizeof);
  57     }
  58     // encode a command that takes info
  59     uint _IOW(T)(char g, int n)
  60     {
  61         return _IOC!(T)(IOC_IN, cast(uint)g, cast(uint)n, T.sizeof);
  62     }
  63     // encode a command that takes info and returns info
  64     uint _IOWR(T)(char g, int n)
  65     {
  66         return _IOC!(T)(IOC_INOUT, cast(uint)g, cast(uint)n, T.sizeof);
  67     }
  68 }
  69 else version (FreeBSD)
  70 {
  71     /* FreeBSD ioctl's encode the command in the lower 16-bits
  72      * and the size of any in/out parameters in the lower 13 bits of the upper
  73      * 16-bits of a 32 bit unsigned integer. The high 3 bits of the upper
  74      * 16-bits encode the in/out status of the parameter.
  75      */
  76     enum uint IOCPARM_SHIFT = 13; // number of bits for ioctl size
  77     enum uint IOCPARM_MASK = ((1 << IOCPARM_SHIFT) - 1); // parameter length mask
  78     uint IOCPARM_LEN(uint x) // to extract the encoded parameter length
  79     {
  80         return ((x >> 16) & IOCPARM_MASK);
  81     }
  82     uint IOCBASECMD(uint x) // to extract the encoded command
  83     {
  84         return (x & ~(IOCPARM_MASK << 16));
  85     }
  86     uint IOCGROUP(uint x) // to extract the encoded group
  87     {
  88         return ((x >> 8) & 0xff);
  89     }
  90
  91     enum uint IOCPARM_MAX = (1 << IOCPARM_SHIFT); // max size of ioctl args
  92
  93     enum uint IOC_VOID = 0x20000000; // no parameters
  94     enum uint IOC_OUT = 0x40000000; // copy parameters back
  95     enum uint IOC_IN = 0x80000000; // copy parameters into
  96     enum uint IOC_INOUT = (IOC_IN | IOC_OUT);
  97     enum uint IOC_DIRMASK = (IOC_VOID|IOC_OUT|IOC_IN);
  98
  99     // encode the ioctl info into 32 bits
 100     uint _IOC(uint inorout, uint group, uint num, size_t len)
 101     {
 102         return (inorout | ((len & IOCPARM_MASK) << 16) | (group << 8) | num);
 103     }
 104
 105     // encode a command with no parameters
 106     uint _IO(char g, int n)
 107     {
 108         return _IOC(IOC_VOID, cast(uint)g, cast(uint)n, cast(size_t)0);
 109     }
 110     uint _IOWINT(char g, int n)
 111     {
 112         return _IOC(IOC_VOID, cast(uint)g, cast(uint)n, int.sizeof);
 113     }
 114     // encode a command that returns info
 115     uint _IOR(T)(char g, int n)
 116     {
 117         return _IOC(IOC_OUT, cast(uint)g, cast(uint)n, T.sizeof);
 118     }
 119     // encode a command that takes info
 120     uint _IOW(T)(char g, int n)
 121     {
 122         return _IOC(IOC_IN, cast(uint)g, cast(uint)n, T.sizeof);
 123     }
 124     // encode a command that takes info and returns info
 125     uint _IOWR(T)(char g, int n)
 126     {
 127         return _IOC(IOC_INOUT, cast(uint)g, cast(uint)n, T.sizeof);
 128     }
 129 }