1 /** 2 * A library in the Mach-O format, used on macOS. 3 * 4 * Copyright: Copyright (C) 1999-2020 by The D Language Foundation, All Rights Reserved 5 * Authors: $(LINK2 http://www.digitalmars.com, Walter Bright) 6 * License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost License 1.0) 7 * Source: $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/libmach.d, _libmach.d) 8 * Documentation: https://dlang.org/phobos/dmd_libmach.html 9 * Coverage: https://codecov.io/gh/dlang/dmd/src/master/src/dmd/libmach.d 10 */ 11 12 module dmd.libmach; 13 14 version(OSX): 15 16 import core.stdc.time; 17 import core.stdc.string; 18 import core.stdc.stdlib; 19 import core.stdc.stdio; 20 import core.stdc.config; 21 22 import core.sys.posix.sys.stat; 23 import core.sys.posix.unistd; 24 25 import dmd.globals; 26 import dmd.lib; 27 import dmd.utils; 28 29 import dmd.root.array; 30 import dmd.root.file; 31 import dmd.root.filename; 32 import dmd.root.outbuffer; 33 import dmd.root.port; 34 import dmd.root.rmem; 35 import dmd.root.string; 36 import dmd.root.stringtable; 37 38 import dmd.scanmach; 39 40 // Entry point (only public symbol in this module). 41 public extern (C++) Library LibMach_factory() 42 { 43 return new LibMach(); 44 } 45 46 private: // for the remainder of this module 47 48 enum LOG = false; 49 50 struct MachObjSymbol 51 { 52 const(char)[] name; // still has a terminating 0 53 MachObjModule* om; 54 } 55 56 alias MachObjModules = Array!(MachObjModule*); 57 alias MachObjSymbols = Array!(MachObjSymbol*); 58 59 final class LibMach : Library 60 { 61 MachObjModules objmodules; // MachObjModule[] 62 MachObjSymbols objsymbols; // MachObjSymbol[] 63 StringTable!(MachObjSymbol*) tab; 64 65 extern (D) this() 66 { 67 tab._init(14_000); 68 } 69 70 /*************************************** 71 * Add object module or library to the library. 72 * Examine the buffer to see which it is. 73 * If the buffer is NULL, use module_name as the file name 74 * and load the file. 75 */ 76 override void addObject(const(char)[] module_name, const ubyte[] buffer) 77 { 78 static if (LOG) 79 { 80 printf("LibMach::addObject(%.*s)\n", 81 cast(int)module_name.length, module_name.ptr); 82 } 83 84 void corrupt(int reason) 85 { 86 error("corrupt Mach object module %.*s %d", 87 cast(int)module_name.length, module_name.ptr, reason); 88 } 89 90 int fromfile = 0; 91 auto buf = buffer.ptr; 92 auto buflen = buffer.length; 93 if (!buf) 94 { 95 assert(module_name[0]); 96 // read file and take buffer ownership 97 auto data = readFile(Loc.initial, module_name).extractSlice(); 98 buf = data.ptr; 99 buflen = data.length; 100 fromfile = 1; 101 } 102 if (buflen < 16) 103 { 104 static if (LOG) 105 { 106 printf("buf = %p, buflen = %d\n", buf, buflen); 107 } 108 return corrupt(__LINE__); 109 } 110 if (memcmp(buf, "!<arch>\n".ptr, 8) == 0) 111 { 112 /* Library file. 113 * Pull each object module out of the library and add it 114 * to the object module array. 115 */ 116 static if (LOG) 117 { 118 printf("archive, buf = %p, buflen = %d\n", buf, buflen); 119 } 120 uint offset = 8; 121 char* symtab = null; 122 uint symtab_size = 0; 123 uint mstart = cast(uint)objmodules.dim; 124 while (offset < buflen) 125 { 126 if (offset + MachLibHeader.sizeof >= buflen) 127 return corrupt(__LINE__); 128 MachLibHeader* header = cast(MachLibHeader*)(cast(ubyte*)buf + offset); 129 offset += MachLibHeader.sizeof; 130 char* endptr = null; 131 uint size = cast(uint)strtoul(header.file_size.ptr, &endptr, 10); 132 if (endptr >= header.file_size.ptr + 10 || *endptr != ' ') 133 return corrupt(__LINE__); 134 if (offset + size > buflen) 135 return corrupt(__LINE__); 136 if (memcmp(header.object_name.ptr, "__.SYMDEF ".ptr, 16) == 0 || 137 memcmp(header.object_name.ptr, "__.SYMDEF SORTED".ptr, 16) == 0) 138 { 139 /* Instead of rescanning the object modules we pull from a 140 * library, just use the already created symbol table. 141 */ 142 if (symtab) 143 return corrupt(__LINE__); 144 symtab = cast(char*)buf + offset; 145 symtab_size = size; 146 if (size < 4) 147 return corrupt(__LINE__); 148 } 149 else 150 { 151 auto om = new MachObjModule(); 152 om.base = cast(ubyte*)buf + offset - MachLibHeader.sizeof; 153 om.length = cast(uint)(size + MachLibHeader.sizeof); 154 om.offset = 0; 155 const n = cast(const(char)*)(om.base + MachLibHeader.sizeof); 156 om.name = n.toDString(); 157 om.file_time = cast(uint)strtoul(header.file_time.ptr, &endptr, 10); 158 om.user_id = cast(uint)strtoul(header.user_id.ptr, &endptr, 10); 159 om.group_id = cast(uint)strtoul(header.group_id.ptr, &endptr, 10); 160 om.file_mode = cast(uint)strtoul(header.file_mode.ptr, &endptr, 8); 161 om.scan = 0; // don't scan object module for symbols 162 objmodules.push(om); 163 } 164 offset += (size + 1) & ~1; 165 } 166 if (offset != buflen) 167 return corrupt(__LINE__); 168 /* Scan the library's symbol table, and insert it into our own. 169 * We use this instead of rescanning the object module, because 170 * the library's creator may have a different idea of what symbols 171 * go into the symbol table than we do. 172 * This is also probably faster. 173 */ 174 uint nsymbols = Port.readlongLE(symtab) / 8; 175 char* s = symtab + 4 + nsymbols * 8 + 4; 176 if (4 + nsymbols * 8 + 4 > symtab_size) 177 return corrupt(__LINE__); 178 for (uint i = 0; i < nsymbols; i++) 179 { 180 uint soff = Port.readlongLE(symtab + 4 + i * 8); 181 const(char)* name = s + soff; 182 size_t namelen = strlen(name); 183 //printf("soff = x%x name = %s\n", soff, name); 184 if (s + namelen + 1 - symtab > symtab_size) 185 return corrupt(__LINE__); 186 uint moff = Port.readlongLE(symtab + 4 + i * 8 + 4); 187 //printf("symtab[%d] moff = x%x x%x, name = %s\n", i, moff, moff + sizeof(Header), name); 188 for (uint m = mstart; 1; m++) 189 { 190 if (m == objmodules.dim) 191 return corrupt(__LINE__); // didn't find it 192 MachObjModule* om = objmodules[m]; 193 //printf("\tom offset = x%x\n", (char *)om.base - (char *)buf); 194 if (moff == cast(char*)om.base - cast(char*)buf) 195 { 196 addSymbol(om, name[0 .. namelen], 1); 197 //if (mstart == m) 198 // mstart++; 199 break; 200 } 201 } 202 } 203 return; 204 } 205 /* It's an object module 206 */ 207 auto om = new MachObjModule(); 208 om.base = cast(ubyte*)buf; 209 om.length = cast(uint)buflen; 210 om.offset = 0; 211 const n = FileName.name(module_name); // remove path, but not extension 212 om.name = n; 213 om.scan = 1; 214 if (fromfile) 215 { 216 stat_t statbuf; 217 int i = module_name.toCStringThen!(slice => stat(slice.ptr, &statbuf)); 218 if (i == -1) // error, errno is set 219 return corrupt(__LINE__); 220 om.file_time = statbuf.st_ctime; 221 om.user_id = statbuf.st_uid; 222 om.group_id = statbuf.st_gid; 223 om.file_mode = statbuf.st_mode; 224 } 225 else 226 { 227 /* Mock things up for the object module file that never was 228 * actually written out. 229 */ 230 __gshared uid_t uid; 231 __gshared gid_t gid; 232 __gshared int _init; 233 if (!_init) 234 { 235 _init = 1; 236 uid = getuid(); 237 gid = getgid(); 238 } 239 time(&om.file_time); 240 om.user_id = uid; 241 om.group_id = gid; 242 om.file_mode = (1 << 15) | (6 << 6) | (4 << 3) | (4 << 0); // 0100644 243 } 244 objmodules.push(om); 245 } 246 247 /*****************************************************************************/ 248 249 void addSymbol(MachObjModule* om, const(char)[] name, int pickAny = 0) 250 { 251 static if (LOG) 252 { 253 printf("LibMach::addSymbol(%s, %s, %d)\n", om.name.ptr, name.ptr, pickAny); 254 } 255 version (none) 256 { 257 // let linker sort out duplicates 258 StringValue* s = tab.insert(name.ptr, name.length, null); 259 if (!s) 260 { 261 // already in table 262 if (!pickAny) 263 { 264 s = tab.lookup(name.ptr, name.length); 265 assert(s); 266 MachObjSymbol* os = cast(MachObjSymbol*)s.ptrvalue; 267 error("multiple definition of %s: %s and %s: %s", om.name.ptr, name.ptr, os.om.name.ptr, os.name.ptr); 268 } 269 } 270 else 271 { 272 auto os = new MachObjSymbol(); 273 os.name = xarraydup(name); 274 os.om = om; 275 s.ptrvalue = cast(void*)os; 276 objsymbols.push(os); 277 } 278 } 279 else 280 { 281 auto os = new MachObjSymbol(); 282 os.name = xarraydup(name); 283 os.om = om; 284 objsymbols.push(os); 285 } 286 } 287 288 private: 289 /************************************ 290 * Scan single object module for dictionary symbols. 291 * Send those symbols to LibMach::addSymbol(). 292 */ 293 void scanObjModule(MachObjModule* om) 294 { 295 static if (LOG) 296 { 297 printf("LibMach::scanObjModule(%s)\n", om.name.ptr); 298 } 299 300 extern (D) void addSymbol(const(char)[] name, int pickAny) 301 { 302 this.addSymbol(om, name, pickAny); 303 } 304 305 scanMachObjModule(&addSymbol, om.base[0 .. om.length], om.name.ptr, loc); 306 } 307 308 /*****************************************************************************/ 309 /*****************************************************************************/ 310 /********************************************** 311 * Create and write library to libbuf. 312 * The library consists of: 313 * !<arch>\n 314 * header 315 * dictionary 316 * object modules... 317 */ 318 protected override void WriteLibToBuffer(OutBuffer* libbuf) 319 { 320 static if (LOG) 321 { 322 printf("LibMach::WriteLibToBuffer()\n"); 323 } 324 __gshared char* pad = [0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A, 0x0A]; 325 /************* Scan Object Modules for Symbols ******************/ 326 for (size_t i = 0; i < objmodules.dim; i++) 327 { 328 MachObjModule* om = objmodules[i]; 329 if (om.scan) 330 { 331 scanObjModule(om); 332 } 333 } 334 /************* Determine module offsets ******************/ 335 uint moffset = 8 + MachLibHeader.sizeof + 4 + 4; 336 for (size_t i = 0; i < objsymbols.dim; i++) 337 { 338 MachObjSymbol* os = objsymbols[i]; 339 moffset += 8 + os.name.length + 1; 340 } 341 moffset = (moffset + 3) & ~3; 342 //if (moffset & 4) 343 // moffset += 4; 344 uint hoffset = moffset; 345 static if (LOG) 346 { 347 printf("\tmoffset = x%x\n", moffset); 348 } 349 for (size_t i = 0; i < objmodules.dim; i++) 350 { 351 MachObjModule* om = objmodules[i]; 352 moffset += moffset & 1; 353 om.offset = moffset; 354 if (om.scan) 355 { 356 const slen = om.name.length; 357 int nzeros = 8 - ((slen + 4) & 7); 358 if (nzeros < 4) 359 nzeros += 8; // emulate mysterious behavior of ar 360 int filesize = om.length; 361 filesize = (filesize + 7) & ~7; 362 moffset += MachLibHeader.sizeof + slen + nzeros + filesize; 363 } 364 else 365 { 366 moffset += om.length; 367 } 368 } 369 libbuf.reserve(moffset); 370 /************* Write the library ******************/ 371 libbuf.write("!<arch>\n"); 372 MachObjModule om; 373 om.base = null; 374 om.length = cast(uint)(hoffset - (8 + MachLibHeader.sizeof)); 375 om.offset = 8; 376 om.name = ""; 377 .time(&om.file_time); 378 om.user_id = getuid(); 379 om.group_id = getgid(); 380 om.file_mode = (1 << 15) | (6 << 6) | (4 << 3) | (4 << 0); // 0100644 381 MachLibHeader h; 382 MachOmToHeader(&h, &om); 383 memcpy(h.object_name.ptr, "__.SYMDEF".ptr, 9); 384 int len = sprintf(h.file_size.ptr, "%u", om.length); 385 assert(len <= 10); 386 memset(h.file_size.ptr + len, ' ', 10 - len); 387 libbuf.write((&h)[0 .. 1]); 388 char[4] buf; 389 Port.writelongLE(cast(uint)(objsymbols.dim * 8), buf.ptr); 390 libbuf.write(buf[0 .. 4]); 391 int stringoff = 0; 392 for (size_t i = 0; i < objsymbols.dim; i++) 393 { 394 MachObjSymbol* os = objsymbols[i]; 395 Port.writelongLE(stringoff, buf.ptr); 396 libbuf.write(buf[0 .. 4]); 397 Port.writelongLE(os.om.offset, buf.ptr); 398 libbuf.write(buf[0 .. 4]); 399 stringoff += os.name.length + 1; 400 } 401 Port.writelongLE(stringoff, buf.ptr); 402 libbuf.write(buf[0 .. 4]); 403 for (size_t i = 0; i < objsymbols.dim; i++) 404 { 405 MachObjSymbol* os = objsymbols[i]; 406 libbuf.writestring(os.name); 407 libbuf.writeByte(0); 408 } 409 while (libbuf.length & 3) 410 libbuf.writeByte(0); 411 //if (libbuf.length & 4) 412 // libbuf.write(pad[0 .. 4]); 413 static if (LOG) 414 { 415 printf("\tlibbuf.moffset = x%x\n", libbuf.length); 416 } 417 assert(libbuf.length == hoffset); 418 /* Write out each of the object modules 419 */ 420 for (size_t i = 0; i < objmodules.dim; i++) 421 { 422 MachObjModule* om2 = objmodules[i]; 423 if (libbuf.length & 1) 424 libbuf.writeByte('\n'); // module alignment 425 assert(libbuf.length == om2.offset); 426 if (om2.scan) 427 { 428 MachOmToHeader(&h, om2); 429 libbuf.write((&h)[0 .. 1]); // module header 430 libbuf.write(om2.name.ptr[0 .. om2.name.length]); 431 int nzeros = 8 - ((om2.name.length + 4) & 7); 432 if (nzeros < 4) 433 nzeros += 8; // emulate mysterious behavior of ar 434 libbuf.fill0(nzeros); 435 libbuf.write(om2.base[0 .. om2.length]); // module contents 436 // obj modules are padded out to 8 bytes in length with 0x0A 437 int filealign = om2.length & 7; 438 if (filealign) 439 { 440 libbuf.write(pad[0 .. 8 - filealign]); 441 } 442 } 443 else 444 { 445 libbuf.write(om2.base[0 .. om2.length]); // module contents 446 } 447 } 448 static if (LOG) 449 { 450 printf("moffset = x%x, libbuf.length = x%x\n", moffset, libbuf.length); 451 } 452 assert(libbuf.length == moffset); 453 } 454 } 455 456 /*****************************************************************************/ 457 /*****************************************************************************/ 458 struct MachObjModule 459 { 460 ubyte* base; // where are we holding it in memory 461 uint length; // in bytes 462 uint offset; // offset from start of library 463 const(char)[] name; // module name (file name) with terminating 0 464 c_long file_time; // file time 465 uint user_id; 466 uint group_id; 467 uint file_mode; 468 int scan; // 1 means scan for symbols 469 } 470 471 enum MACH_OBJECT_NAME_SIZE = 16; 472 473 struct MachLibHeader 474 { 475 char[MACH_OBJECT_NAME_SIZE] object_name; 476 char[12] file_time; 477 char[6] user_id; 478 char[6] group_id; 479 char[8] file_mode; // in octal 480 char[10] file_size; 481 char[2] trailer; 482 } 483 484 extern (C++) void MachOmToHeader(MachLibHeader* h, MachObjModule* om) 485 { 486 const slen = om.name.length; 487 int nzeros = 8 - ((slen + 4) & 7); 488 if (nzeros < 4) 489 nzeros += 8; // emulate mysterious behavior of ar 490 size_t len = sprintf(h.object_name.ptr, "#1/%ld", slen + nzeros); 491 memset(h.object_name.ptr + len, ' ', MACH_OBJECT_NAME_SIZE - len); 492 /* In the following sprintf's, don't worry if the trailing 0 493 * that sprintf writes goes off the end of the field. It will 494 * write into the next field, which we will promptly overwrite 495 * anyway. (So make sure to write the fields in ascending order.) 496 */ 497 len = sprintf(h.file_time.ptr, "%llu", cast(long)om.file_time); 498 assert(len <= 12); 499 memset(h.file_time.ptr + len, ' ', 12 - len); 500 if (om.user_id > 999_999) // yes, it happens 501 om.user_id = 0; // don't really know what to do here 502 len = sprintf(h.user_id.ptr, "%u", om.user_id); 503 assert(len <= 6); 504 memset(h.user_id.ptr + len, ' ', 6 - len); 505 if (om.group_id > 999_999) // yes, it happens 506 om.group_id = 0; // don't really know what to do here 507 len = sprintf(h.group_id.ptr, "%u", om.group_id); 508 assert(len <= 6); 509 memset(h.group_id.ptr + len, ' ', 6 - len); 510 len = sprintf(h.file_mode.ptr, "%o", om.file_mode); 511 assert(len <= 8); 512 memset(h.file_mode.ptr + len, ' ', 8 - len); 513 int filesize = om.length; 514 filesize = (filesize + 7) & ~7; 515 len = sprintf(h.file_size.ptr, "%lu", slen + nzeros + filesize); 516 assert(len <= 10); 517 memset(h.file_size.ptr + len, ' ', 10 - len); 518 h.trailer[0] = '`'; 519 h.trailer[1] = '\n'; 520 }