mcs/tools/mkbundle/mkbundle.cs

   1 //
   2 // mkbundle: tool to create bundles.
   3 //
   4 // Based on the `make-bundle' Perl script written by Paolo Molaro (lupus@debian.org)
   5 //
   6 // Author:
   7 //   Miguel de Icaza
   8 //
   9 // (C) Novell, Inc 2004
  10 //
  11 using System;
  12 using System.Diagnostics;
  13 using System.Xml;
  14 using System.Collections.Generic;
  15 using System.IO;
  16 using System.IO.Compression;
  17 using System.Runtime.InteropServices;
  18 using System.Text;
  19 using IKVM.Reflection;
  20
  21
  22 using System.Threading.Tasks;
  23
  24 class MakeBundle {
  25         static string output = "a.out";
  26         static string object_out = null;
  27         static List<string> link_paths = new List<string> ();
  28         static bool autodeps = false;
  29         static bool keeptemp = false;
  30         static bool compile_only = false;
  31         static bool static_link = false;
  32         static string config_file = null;
  33         static string machine_config_file = null;
  34         static string config_dir = null;
  35         static string style = "linux";
  36         static bool compress;
  37         static bool nomain;
  38         static bool? use_dos2unix = null;
  39         static bool skip_scan;
  40         static string ctor_func;
  41
  42         static int Main (string [] args)
  43         {
  44                 List<string> sources = new List<string> ();
  45                 int top = args.Length;
  46                 link_paths.Add (".");
  47
  48                 DetectOS ();
  49
  50                 for (int i = 0; i < top; i++){
  51                         switch (args [i]){
  52                         case "--help": case "-h": case "-?":
  53                                 Help ();
  54                                 return 1;
  55
  56                         case "-c":
  57                                 compile_only = true;
  58                                 break;
  59
  60                         case "-o":
  61                                 if (i+1 == top){
  62                                         Help ();
  63                                         return 1;
  64                                 }
  65                                 output = args [++i];
  66                                 break;
  67
  68                         case "-oo":
  69                                 if (i+1 == top){
  70                                         Help ();
  71                                         return 1;
  72                                 }
  73                                 object_out = args [++i];
  74                                 break;
  75
  76                         case "-L":
  77                                 if (i+1 == top){
  78                                         Help ();
  79                                         return 1;
  80                                 }
  81                                 link_paths.Add (args [++i]);
  82                                 break;
  83
  84                         case "--nodeps":
  85                                 autodeps = false;
  86                                 break;
  87
  88                         case "--deps":
  89                                 autodeps = true;
  90                                 break;
  91
  92                         case "--keeptemp":
  93                                 keeptemp = true;
  94                                 break;
  95                         case "--static":
  96                                 static_link = true;
  97                                 Console.WriteLine ("Note that statically linking the LGPL Mono runtime has more licensing restrictions than dynamically linking.");
  98                                 Console.WriteLine ("See http://www.mono-project.com/Licensing for details on licensing.");
  99                                 break;
 100                         case "--config":
 101                                 if (i+1 == top) {
 102                                         Help ();
 103                                         return 1;
 104                                 }
 105
 106                                 config_file = args [++i];
 107                                 break;
 108                         case "--machine-config":
 109                                 if (i+1 == top) {
 110                                         Help ();
 111                                         return 1;
 112                                 }
 113
 114                                 machine_config_file = args [++i];
 115
 116                                 Console.WriteLine ("WARNING:\n  Check that the machine.config file you are bundling\n  doesn't contain sensitive information specific to this machine.");
 117                                 break;
 118                         case "--config-dir":
 119                                 if (i+1 == top) {
 120                                         Help ();
 121                                         return 1;
 122                                 }
 123
 124                                 config_dir = args [++i];
 125                                 break;
 126                         case "-z":
 127                                 compress = true;
 128                                 break;
 129                         case "--nomain":
 130                                 nomain = true;
 131                                 break;
 132                         case "--style":
 133                                 if (i+1 == top) {
 134                                         Help ();
 135                                         return 1;
 136                                 }
 137                                 style = args [++i];
 138                                 switch (style) {
 139                                 case "windows":
 140                                 case "mac":
 141                                 case "linux":
 142                                         break;
 143                                 default:
 144                                         Console.Error.WriteLine ("Invalid style '{0}' - only 'windows', 'mac' and 'linux' are supported for --style argument", style);
 145                                         return 1;
 146                                 }
 147
 148                                 break;
 149                         case "--skip-scan":
 150                                 skip_scan = true;
 151                                 break;
 152                         case "--static-ctor":
 153                                 if (i+1 == top) {
 154                                         Help ();
 155                                         return 1;
 156                                 }
 157                                 ctor_func = args [++i];
 158                                 break;
 159                         default:
 160                                 sources.Add (args [i]);
 161                                 break;
 162                         }
 163
 164                         if (static_link && style == "windows") {
 165                                 Console.Error.WriteLine ("The option `{0}' is not supported on this platform.", args [i]);
 166                                 return 1;
 167                         }
 168                 }
 169
 170                 Console.WriteLine ("Sources: {0} Auto-dependencies: {1}", sources.Count, autodeps);
 171                 if (sources.Count == 0 || output == null) {
 172                         Help ();
 173                         Environment.Exit (1);
 174                 }
 175
 176                 List<string> assemblies = LoadAssemblies (sources);
 177                 List<string> files = new List<string> ();
 178                 foreach (string file in assemblies)
 179                         if (!QueueAssembly (files, file))
 180                                 return 1;
 181
 182                 GenerateBundles (files);
 183                 //GenerateJitWrapper ();
 184
 185                 return 0;
 186         }
 187
 188         static void WriteSymbol (StreamWriter sw, string name, long size)
 189         {
 190                 switch (style){
 191                 case "linux":
 192                         sw.WriteLine (
 193                                 ".globl {0}\n" +
 194                                 "\t.section .rodata\n" +
 195                                 "\t.p2align 5\n" +
 196                                 "\t.type {0}, \"object\"\n" +
 197                                 "\t.size {0}, {1}\n" +
 198                                 "{0}:\n",
 199                                 name, size);
 200                         break;
 201                 case "osx":
 202                         sw.WriteLine (
 203                                 "\t.section __TEXT,__text,regular,pure_instructions\n" +
 204                                 "\t.globl _{0}\n" +
 205                                 "\t.data\n" +
 206                                 "\t.align 4\n" +
 207                                 "_{0}:\n",
 208                                 name, size);
 209                         break;
 210                 case "windows":
 211                         sw.WriteLine (
 212                                 ".globl _{0}\n" +
 213                                 "\t.section .rdata,\"dr\"\n" +
 214                                 "\t.align 32\n" +
 215                                 "_{0}:\n",
 216                                 name, size);
 217                         break;
 218                 }
 219         }
 220
 221         static string [] chars = new string [256];
 222
 223         static void WriteBuffer (StreamWriter ts, Stream stream, byte[] buffer)
 224         {
 225                 int n;
 226
 227                 // Preallocate the strings we need.
 228                 if (chars [0] == null) {
 229                         for (int i = 0; i < chars.Length; i++)
 230                                 chars [i] = string.Format ("{0}", i.ToString ());
 231                 }
 232
 233                 while ((n = stream.Read (buffer, 0, buffer.Length)) != 0) {
 234                         int count = 0;
 235                         for (int i = 0; i < n; i++) {
 236                                 if (count % 32 == 0) {
 237                                         ts.Write ("\n\t.byte ");
 238                                 } else {
 239                                         ts.Write (",");
 240                                 }
 241                                 ts.Write (chars [buffer [i]]);
 242                                 count ++;
 243                         }
 244                 }
 245
 246                 ts.WriteLine ();
 247         }
 248
 249         static void GenerateBundles (List<string> files)
 250         {
 251                 string temp_s = "temp.s"; // Path.GetTempFileName ();
 252                 string temp_c = "temp.c";
 253                 string temp_o = "temp.o";
 254
 255                 if (compile_only)
 256                         temp_c = output;
 257                 if (object_out != null)
 258                         temp_o = object_out;
 259
 260                 try {
 261                         List<string> c_bundle_names = new List<string> ();
 262                         List<string[]> config_names = new List<string[]> ();
 263
 264                         using (StreamWriter ts = new StreamWriter (File.Create (temp_s))) {
 265                         using (StreamWriter tc = new StreamWriter (File.Create (temp_c))) {
 266                         string prog = null;
 267
 268 #if XAMARIN_ANDROID
 269                         tc.WriteLine ("/* This source code was produced by mkbundle, do not edit */");
 270                         tc.WriteLine ("\n#ifndef NULL\n#define NULL (void *)0\n#endif");
 271                         tc.WriteLine (@"
 272 typedef struct {
 273         const char *name;
 274         const unsigned char *data;
 275         const unsigned int size;
 276 } MonoBundledAssembly;
 277 void          mono_register_bundled_assemblies (const MonoBundledAssembly **assemblies);
 278 void          mono_register_config_for_assembly (const char* assembly_name, const char* config_xml);
 279 ");
 280 #else
 281                         tc.WriteLine ("#include <mono/metadata/mono-config.h>");
 282                         tc.WriteLine ("#include <mono/metadata/assembly.h>\n");
 283 #endif
 284
 285                         if (compress) {
 286                                 tc.WriteLine ("typedef struct _compressed_data {");
 287                                 tc.WriteLine ("\tMonoBundledAssembly assembly;");
 288                                 tc.WriteLine ("\tint compressed_size;");
 289                                 tc.WriteLine ("} CompressedAssembly;\n");
 290                         }
 291
 292                         object monitor = new object ();
 293
 294                         var streams = new Dictionary<string, Stream> ();
 295                         var sizes = new Dictionary<string, long> ();
 296
 297                         // Do the file reading and compression in parallel
 298                         Action<string> body = delegate (string url) {
 299                                 string fname = new Uri (url).LocalPath;
 300                                 Stream stream = File.OpenRead (fname);
 301
 302                                 long real_size = stream.Length;
 303                                 int n;
 304                                 if (compress) {
 305                                         byte[] cbuffer = new byte [8192];
 306                                         MemoryStream ms = new MemoryStream ();
 307                                         GZipStream deflate = new GZipStream (ms, CompressionMode.Compress, leaveOpen:true);
 308                                         while ((n = stream.Read (cbuffer, 0, cbuffer.Length)) != 0){
 309                                                 deflate.Write (cbuffer, 0, n);
 310                                         }
 311                                         stream.Close ();
 312                                         deflate.Close ();
 313                                         byte [] bytes = ms.GetBuffer ();
 314                                         stream = new MemoryStream (bytes, 0, (int) ms.Length, false, false);
 315                                 }
 316
 317                                 lock (monitor) {
 318                                         streams [url] = stream;
 319                                         sizes [url] = real_size;
 320                                 }
 321                         };
 322
 323                         //#if NET_4_5
 324 #if FALSE
 325                         Parallel.ForEach (files, body);
 326 #else
 327                         foreach (var url in files)
 328                                 body (url);
 329 #endif
 330
 331                         // The non-parallel part
 332                         byte [] buffer = new byte [8192];
 333                         foreach (var url in files) {
 334                                 string fname = new Uri (url).LocalPath;
 335                                 string aname = Path.GetFileName (fname);
 336                                 string encoded = aname.Replace ("-", "_").Replace (".", "_");
 337
 338                                 if (prog == null)
 339                                         prog = aname;
 340
 341                                 var stream = streams [url];
 342                                 var real_size = sizes [url];
 343
 344                                 Console.WriteLine ("   embedding: " + fname);
 345
 346                                 WriteSymbol (ts, "assembly_data_" + encoded, stream.Length);
 347
 348                                 WriteBuffer (ts, stream, buffer);
 349
 350                                 if (compress) {
 351                                         tc.WriteLine ("extern const unsigned char assembly_data_{0} [];", encoded);
 352                                         tc.WriteLine ("static CompressedAssembly assembly_bundle_{0} = {{{{\"{1}\"," +
 353                                                                   " assembly_data_{0}, {2}}}, {3}}};",
 354                                                                   encoded, aname, real_size, stream.Length);
 355                                         double ratio = ((double) stream.Length * 100) / real_size;
 356                                         Console.WriteLine ("   compression ratio: {0:.00}%", ratio);
 357                                 } else {
 358                                         tc.WriteLine ("extern const unsigned char assembly_data_{0} [];", encoded);
 359                                         tc.WriteLine ("static const MonoBundledAssembly assembly_bundle_{0} = {{\"{1}\", assembly_data_{0}, {2}}};",
 360                                                                   encoded, aname, real_size);
 361                                 }
 362                                 stream.Close ();
 363
 364                                 c_bundle_names.Add ("assembly_bundle_" + encoded);
 365
 366                                 try {
 367                                         FileStream cf = File.OpenRead (fname + ".config");
 368                                         Console.WriteLine (" config from: " + fname + ".config");
 369                                         tc.WriteLine ("extern const unsigned char assembly_config_{0} [];", encoded);
 370                                         WriteSymbol (ts, "assembly_config_" + encoded, cf.Length);
 371                                         WriteBuffer (ts, cf, buffer);
 372                                         ts.WriteLine ();
 373                                         config_names.Add (new string[] {aname, encoded});
 374                                 } catch (FileNotFoundException) {
 375                                         /* we ignore if the config file doesn't exist */
 376                                 }
 377                         }
 378
 379                         if (config_file != null){
 380                                 FileStream conf;
 381                                 try {
 382                                         conf = File.OpenRead (config_file);
 383                                 } catch {
 384                                         Error (String.Format ("Failure to open {0}", config_file));
 385                                         return;
 386                                 }
 387                                 Console.WriteLine ("System config from: " + config_file);
 388                                 tc.WriteLine ("extern const char system_config;");
 389                                 WriteSymbol (ts, "system_config", config_file.Length);
 390
 391                                 WriteBuffer (ts, conf, buffer);
 392                                 // null terminator
 393                                 ts.Write ("\t.byte 0\n");
 394                                 ts.WriteLine ();
 395                         }
 396
 397                         if (machine_config_file != null){
 398                                 FileStream conf;
 399                                 try {
 400                                         conf = File.OpenRead (machine_config_file);
 401                                 } catch {
 402                                         Error (String.Format ("Failure to open {0}", machine_config_file));
 403                                         return;
 404                                 }
 405                                 Console.WriteLine ("Machine config from: " + machine_config_file);
 406                                 tc.WriteLine ("extern const char machine_config;");
 407                                 WriteSymbol (ts, "machine_config", machine_config_file.Length);
 408
 409                                 WriteBuffer (ts, conf, buffer);
 410                                 ts.Write ("\t.byte 0\n");
 411                                 ts.WriteLine ();
 412                         }
 413                         ts.Close ();
 414
 415                         string assembler = GetEnv ("AS", IsUnix ? "as" : "i686-pc-mingw32-as");
 416
 417                         Console.WriteLine ("Compiling:");
 418                         string cmd = String.Format ("{0} -o {1} {2} ", assembler, temp_o, temp_s);
 419                         int ret = Execute (cmd);
 420                         if (ret != 0){
 421                                 Error ("[Fail]");
 422                                 return;
 423                         }
 424
 425                         if (compress)
 426                                 tc.WriteLine ("\nstatic const CompressedAssembly *compressed [] = {");
 427                         else
 428                                 tc.WriteLine ("\nstatic const MonoBundledAssembly *bundled [] = {");
 429
 430                         foreach (string c in c_bundle_names){
 431                                 tc.WriteLine ("\t&{0},", c);
 432                         }
 433                         tc.WriteLine ("\tNULL\n};\n");
 434                         tc.WriteLine ("static char *image_name = \"{0}\";", prog);
 435
 436                         if (ctor_func != null) {
 437                                 tc.WriteLine ("\nextern void {0} (void);", ctor_func);
 438                                 tc.WriteLine ("\n__attribute__ ((constructor)) static void mono_mkbundle_ctor (void)");
 439                                 tc.WriteLine ("{{\n\t{0} ();\n}}", ctor_func);
 440                         }
 441
 442                         tc.WriteLine ("\nstatic void install_dll_config_files (void) {\n");
 443                         foreach (string[] ass in config_names){
 444                                 tc.WriteLine ("\tmono_register_config_for_assembly (\"{0}\", assembly_config_{1});\n", ass [0], ass [1]);
 445                         }
 446                         if (config_file != null)
 447                                 tc.WriteLine ("\tmono_config_parse_memory (&system_config);\n");
 448                         if (machine_config_file != null)
 449                                 tc.WriteLine ("\tmono_register_machine_config (&machine_config);\n");
 450                         tc.WriteLine ("}\n");
 451
 452                         if (config_dir != null)
 453                                 tc.WriteLine ("static const char *config_dir = \"{0}\";", config_dir);
 454                         else
 455                                 tc.WriteLine ("static const char *config_dir = NULL;");
 456
 457                         Stream template_stream;
 458                         if (compress) {
 459                                 template_stream = System.Reflection.Assembly.GetAssembly (typeof(MakeBundle)).GetManifestResourceStream ("template_z.c");
 460                         } else {
 461                                 template_stream = System.Reflection.Assembly.GetAssembly (typeof(MakeBundle)).GetManifestResourceStream ("template.c");
 462                         }
 463
 464                         StreamReader s = new StreamReader (template_stream);
 465                         string template = s.ReadToEnd ();
 466                         tc.Write (template);
 467
 468                         if (!nomain) {
 469                                 Stream template_main_stream = System.Reflection.Assembly.GetAssembly (typeof(MakeBundle)).GetManifestResourceStream ("template_main.c");
 470                                 StreamReader st = new StreamReader (template_main_stream);
 471                                 string maintemplate = st.ReadToEnd ();
 472                                 tc.Write (maintemplate);
 473                         }
 474
 475                         tc.Close ();
 476
 477                         if (compile_only)
 478                                 return;
 479
 480                         string zlib = (compress ? "-lz" : "");
 481                         string debugging = "-g";
 482                         string cc = GetEnv ("CC", IsUnix ? "cc" : "i686-pc-mingw32-gcc");
 483
 484                         if (style == "linux")
 485                                 debugging = "-ggdb";
 486                         if (static_link) {
 487                                 string smonolib;
 488                                 if (style == "osx")
 489                                         smonolib = "`pkg-config --variable=libdir mono-2`/libmono-2.0.a ";
 490                                 else
 491                                         smonolib = "-Wl,-Bstatic -lmono-2.0 -Wl,-Bdynamic ";
 492                                 cmd = String.Format ("{4} -o {2} -Wall `pkg-config --cflags mono-2` {0} {3} " +
 493                                                      "`pkg-config --libs-only-L mono-2` " + smonolib +
 494                                                      "`pkg-config --libs-only-l mono-2 | sed -e \"s/\\-lmono-2.0 //\"` {1}",
 495                                                      temp_c, temp_o, output, zlib, cc);
 496                         } else {
 497
 498                                 cmd = String.Format ("{4} " + debugging + " -o {2} -Wall {0} `pkg-config --cflags --libs mono-2` {3} {1}",
 499                                                      temp_c, temp_o, output, zlib, cc);
 500                         }
 501
 502                         ret = Execute (cmd);
 503                         if (ret != 0){
 504                                 Error ("[Fail]");
 505                                 return;
 506                         }
 507                         Console.WriteLine ("Done");
 508                         }
 509                         }
 510                 } finally {
 511                         if (!keeptemp){
 512                                 if (object_out == null){
 513                                         File.Delete (temp_o);
 514                                 }
 515                                 if (!compile_only){
 516                                         File.Delete (temp_c);
 517                                 }
 518                                 File.Delete (temp_s);
 519                         }
 520                 }
 521         }
 522
 523         static List<string> LoadAssemblies (List<string> sources)
 524         {
 525                 List<string> assemblies = new List<string> ();
 526                 bool error = false;
 527
 528                 foreach (string name in sources){
 529                         try {
 530                                 Assembly a = LoadAssembly (name);
 531
 532                                 if (a == null){
 533                                         error = true;
 534                                         continue;
 535                                 }
 536
 537                                 assemblies.Add (a.CodeBase);
 538                         } catch (Exception e) {
 539                                 if (skip_scan) {
 540                                         Console.WriteLine ("File will not be scanned: {0}", name);
 541                                         assemblies.Add (new Uri (new FileInfo (name).FullName).ToString ());
 542                                 } else {
 543                                         throw;
 544                                 }
 545                         }
 546                 }
 547
 548                 if (error)
 549                         Environment.Exit (1);
 550
 551                 return assemblies;
 552         }
 553
 554         static readonly Universe universe = new Universe ();
 555         static readonly Dictionary<string, string> loaded_assemblies = new Dictionary<string, string> ();
 556
 557         static bool QueueAssembly (List<string> files, string codebase)
 558         {
 559                 // Console.WriteLine ("CODE BASE IS {0}", codebase);
 560                 if (files.Contains (codebase))
 561                         return true;
 562
 563                 var path = new Uri(codebase).LocalPath;
 564                 var name = Path.GetFileName (path);
 565                 string found;
 566                 if (loaded_assemblies.TryGetValue (name, out found)) {
 567                         Error (string.Format ("Duplicate assembly name `{0}'. Both `{1}' and `{2}' use same assembly name.", name, path, found));
 568                         return false;
 569                 }
 570
 571                 loaded_assemblies.Add (name, path);
 572
 573                 files.Add (codebase);
 574                 if (!autodeps)
 575                         return true;
 576                 try {
 577                         Assembly a = universe.LoadFile (path);
 578
 579                         foreach (AssemblyName an in a.GetReferencedAssemblies ()) {
 580                                 a = universe.Load (an.FullName);
 581                                 if (!QueueAssembly (files, a.CodeBase))
 582                                         return false;
 583                         }
 584                 } catch (Exception e) {
 585                         if (!skip_scan)
 586                                 throw;
 587                 }
 588
 589                 return true;
 590         }
 591
 592         static Assembly LoadAssembly (string assembly)
 593         {
 594                 Assembly a;
 595
 596                 try {
 597                         char[] path_chars = { '/', '\\' };
 598
 599                         if (assembly.IndexOfAny (path_chars) != -1) {
 600                                 a = universe.LoadFile (assembly);
 601                         } else {
 602                                 string ass = assembly;
 603                                 if (ass.EndsWith (".dll"))
 604                                         ass = assembly.Substring (0, assembly.Length - 4);
 605                                 a = universe.Load (ass);
 606                         }
 607                         return a;
 608                 } catch (FileNotFoundException){
 609                         string total_log = "";
 610
 611                         foreach (string dir in link_paths){
 612                                 string full_path = Path.Combine (dir, assembly);
 613                                 if (!assembly.EndsWith (".dll") && !assembly.EndsWith (".exe"))
 614                                         full_path += ".dll";
 615
 616                                 try {
 617                                         a = universe.LoadFile (full_path);
 618                                         return a;
 619                                 } catch (FileNotFoundException ff) {
 620                                         total_log += ff.FusionLog;
 621                                         continue;
 622                                 }
 623                         }
 624                         Error ("Cannot find assembly `" + assembly + "'" );
 625                         Console.WriteLine ("Log: \n" + total_log);
 626                 } catch (IKVM.Reflection.BadImageFormatException f) {
 627                         if (skip_scan)
 628                                 throw;
 629                         Error ("Cannot load assembly (bad file format) " + f.Message);
 630                 } catch (FileLoadException f){
 631                         Error ("Cannot load assembly " + f.Message);
 632                 } catch (ArgumentNullException){
 633                         Error("Cannot load assembly (null argument)");
 634                 }
 635                 return null;
 636         }
 637
 638         static void Error (string msg)
 639         {
 640                 Console.Error.WriteLine ("ERROR: " + msg);
 641                 Environment.Exit (1);
 642         }
 643
 644         static void Help ()
 645         {
 646                 Console.WriteLine ("Usage is: mkbundle [options] assembly1 [assembly2...]\n\n" +
 647                                    "Options:\n" +
 648                                    "    -c                  Produce stub only, do not compile\n" +
 649                                    "    -o out              Specifies output filename\n" +
 650                                    "    -oo obj             Specifies output filename for helper object file\n" +
 651                                    "    -L path             Adds `path' to the search path for assemblies\n" +
 652                                    "    --nodeps            Turns off automatic dependency embedding (default)\n" +
 653                                    "    --deps              Turns on automatic dependency embedding\n" +
 654                                    "    --keeptemp          Keeps the temporary files\n" +
 655                                    "    --config F          Bundle system config file `F'\n" +
 656                                    "    --config-dir D      Set MONO_CFG_DIR to `D'\n" +
 657                                    "    --machine-config F  Use the given file as the machine.config for the application.\n" +
 658                                    "    --static            Statically link to mono libs\n" +
 659                                    "    --nomain            Don't include a main() function, for libraries\n" +
 660                                    "    -z                  Compress the assemblies before embedding.\n" +
 661                                    "    --skip-scan         Skip scanning assemblies that could not be loaded (but still embed them).\n" +
 662                                    "    --static-ctor ctor  Add a constructor call to the supplied function.\n" +
 663                                    "                        You need zlib development headers and libraries.\n");
 664         }
 665
 666         [DllImport ("libc")]
 667         static extern int system (string s);
 668         [DllImport ("libc")]
 669         static extern int uname (IntPtr buf);
 670
 671         static void DetectOS ()
 672         {
 673                 if (!IsUnix) {
 674                         Console.WriteLine ("OS is: Windows");
 675                         style = "windows";
 676                         return;
 677                 }
 678
 679                 IntPtr buf = Marshal.AllocHGlobal (8192);
 680                 if (uname (buf) != 0){
 681                         Console.WriteLine ("Warning: Unable to detect OS");
 682                         Marshal.FreeHGlobal (buf);
 683                         return;
 684                 }
 685                 string os = Marshal.PtrToStringAnsi (buf);
 686                 Console.WriteLine ("OS is: " + os);
 687                 if (os == "Darwin")
 688                         style = "osx";
 689
 690                 Marshal.FreeHGlobal (buf);
 691         }
 692
 693         static bool IsUnix {
 694                 get {
 695                         int p = (int) Environment.OSVersion.Platform;
 696                         return ((p == 4) || (p == 128) || (p == 6));
 697                 }
 698         }
 699
 700         static int Execute (string cmdLine)
 701         {
 702                 if (IsUnix) {
 703                         Console.WriteLine (cmdLine);
 704                         return system (cmdLine);
 705                 }
 706
 707 #if XAMARIN_ANDROID
 708                 // on Windows, we have to pipe the output of a
 709                 // `cmd` interpolation to dos2unix, because the shell does not
 710                 // strip the CRLFs generated by the native pkg-config distributed
 711                 // with Mono.
 712                 //
 713                 // But if it's *not* on cygwin, just skip it.
 714
 715                 // check if dos2unix is applicable.
 716                 if (use_dos2unix == null) {
 717                         use_dos2unix = false;
 718                         try {
 719                                 var info = new ProcessStartInfo ("dos2unix");
 720                                 info.CreateNoWindow = true;
 721                                 info.RedirectStandardInput = true;
 722                                 info.UseShellExecute = false;
 723                                 var dos2unix = Process.Start (info);
 724                                 dos2unix.StandardInput.WriteLine ("aaa");
 725                                 dos2unix.StandardInput.WriteLine ("\u0004");
 726                                 dos2unix.StandardInput.Close ();
 727                                 dos2unix.WaitForExit ();
 728                                 if (dos2unix.ExitCode == 0)
 729                                         use_dos2unix = true;
 730                         } catch {
 731                                 // ignore
 732                         }
 733                 }
 734                 // and if there is no dos2unix, just run cmd /c.
 735                 if (use_dos2unix == false) {
 736 #endif
 737                         Console.WriteLine (cmdLine);
 738                         ProcessStartInfo dos2unix = new ProcessStartInfo ();
 739                         dos2unix.UseShellExecute = false;
 740                         dos2unix.FileName = "cmd";
 741                         dos2unix.Arguments = String.Format ("/c \"{0}\"", cmdLine);
 742
 743                         using (Process p = Process.Start (dos2unix)) {
 744                                 p.WaitForExit ();
 745                                 return p.ExitCode;
 746                         }
 747 #if XAMARIN_ANDROID
 748                 }
 749 #endif
 750
 751                 StringBuilder b = new StringBuilder ();
 752                 int count = 0;
 753                 for (int i = 0; i < cmdLine.Length; i++) {
 754                         if (cmdLine [i] == '`') {
 755 #if XAMARIN_ANDROID
 756                                 if (count % 2 != 0) {
 757                                         b.Append ("|dos2unix");
 758                                 }
 759 #endif
 760                                 count++;
 761                         }
 762                         b.Append (cmdLine [i]);
 763                 }
 764                 cmdLine = b.ToString ();
 765                 Console.WriteLine (cmdLine);
 766
 767                 ProcessStartInfo psi = new ProcessStartInfo ();
 768                 psi.UseShellExecute = false;
 769                 psi.FileName = "sh";
 770                 psi.Arguments = String.Format ("-c \"{0}\"", cmdLine);
 771
 772                 using (Process p = Process.Start (psi)) {
 773                         p.WaitForExit ();
 774                         return p.ExitCode;
 775                 }
 776         }
 777
 778         static string GetEnv (string name, string defaultValue)
 779         {
 780                 string s = Environment.GetEnvironmentVariable (name);
 781                 return s != null ? s : defaultValue;
 782         }
 783 }