/usr/lib/gcc/x86_64-linux-gnu/6/include/d/rt/config.d is in libgphobos-6-dev 6.4.0-17ubuntu1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 | /**
* Configuration options for druntime
*
* Copyright: Copyright Digital Mars 2014.
* License: Distributed under the
* $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost Software License 1.0).
* (See accompanying file LICENSE)
* Authors: Rainer Schuetze
* Source: $(DRUNTIMESRC src/rt/_config.d)
*/
module rt.config;
// The default way to configure the runtime is by passing command line arguments
// starting with "--DRT-" and followed by the option name, e.g. "--DRT-gcopt" to
// configure the GC.
// Command line options starting with "--DRT-" are filtered out before calling main,
// so the program will not see them. They are still available via rt_args().
//
// Configuration via the command line can be disabled by declaring a variable for the
// linker to pick up before using it's default from the runtime:
//
// extern(C) __gshared bool rt_cmdline_enabled = false;
//
// Likewise, declare a boolean rt_envvars_enabled to enable configuration via the
// environment variable "DRT_" followed by the option name, e.g. "DRT_GCOPT":
//
// extern(C) __gshared bool rt_envvars_enabled = true;
//
// Setting default configuration properties in the executable can be done by specifying an
// array of options named rt_options:
//
// extern(C) __gshared string[] rt_options = [ "gcopt=precise:1 profile:1"];
//
// Evaluation order of options is rt_options, then environment variables, then command
// line arguments, i.e. if command line arguments are not disabled, they can override
// options specified through the environment or embedded in the executable.
import core.demangle : mangleC;
// put each variable in its own COMDAT by making them template instances
template rt_envvars_enabled()
{
pragma(mangle,mangleC("rt_envvars_enabled")) __gshared bool rt_envvars_enabled = false;
}
template rt_cmdline_enabled()
{
pragma(mangle,mangleC("rt_cmdline_enabled")) __gshared bool rt_cmdline_enabled = true;
}
template rt_options()
{
pragma(mangle,mangleC("rt_options")) __gshared string[] rt_options = [];
}
import core.stdc.ctype : toupper;
import core.stdc.stdlib : getenv;
import core.stdc.string : strlen;
extern extern(C) string[] rt_args() @nogc nothrow;
alias rt_configCallBack = string delegate(string) @nogc nothrow;
/**
* get a druntime config option using standard configuration options
* opt name of the option to retreive
* dg if non-null, passes the option through this
* delegate and only returns its return value if non-null
* reverse reverse the default processing order cmdline/envvar/rt_options
* to allow overwriting settings in the delegate with values
* from higher priority
*
* returns the options' value if
* - set on the command line as "--DRT-<opt>=value" (rt_cmdline_enabled enabled)
* - the environment variable "DRT_<OPT>" is set (rt_envvars_enabled enabled)
* - rt_options[] contains an entry "<opt>=value"
* - null otherwise
*/
string rt_configOption(string opt, scope rt_configCallBack dg = null, bool reverse = false) @nogc nothrow
{
if (!dg)
dg = (string s) => s;
string s = (reverse ? rt_linkOption(opt, dg) : rt_cmdlineOption(opt, dg));
if (s != null)
return s;
s = rt_envvarsOption(opt, dg);
if (s != null)
return s;
s = (reverse ? rt_cmdlineOption(opt, dg) : rt_linkOption(opt, dg));
return s;
}
string rt_cmdlineOption(string opt, scope rt_configCallBack dg) @nogc nothrow
{
if(rt_cmdline_enabled!())
{
foreach (a; rt_args)
{
if (a.length >= opt.length + 7 && a[0..6] == "--DRT-" &&
a[6 .. 6 + opt.length] == opt && a[6 + opt.length] == '=')
{
string s = dg(a[7 + opt.length .. $]);
if (s != null)
return s;
}
}
}
return null;
}
string rt_envvarsOption(string opt, scope rt_configCallBack dg) @nogc nothrow
{
if(rt_envvars_enabled!())
{
if (opt.length >= 32)
assert(0);
char[40] var;
var[0 .. 4] = "DRT_";
foreach (i, c; opt)
var[4 + i] = cast(char) toupper(c);
var[4 + opt.length] = 0;
auto p = getenv(var.ptr);
if (p)
{
string s = dg(cast(string) p[0 .. strlen(p)]);
if (s != null)
return s;
}
}
return null;
}
string rt_linkOption(string opt, scope rt_configCallBack dg) @nogc nothrow
{
foreach (a; rt_options!())
{
if(a.length > opt.length && a[0..opt.length] == opt && a[opt.length] == '=')
{
string s = dg(a[opt.length + 1 .. $]);
if (s != null)
return s;
}
}
return null;
}
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