github.com/muesli/go@v0.0.0-20170208044820-e410d2a81ef2/misc/cgo/testshared/shared_test.go (about) 1 // Copyright 2015 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package shared_test 6 7 import ( 8 "bufio" 9 "bytes" 10 "debug/elf" 11 "encoding/binary" 12 "errors" 13 "fmt" 14 "go/build" 15 "io" 16 "io/ioutil" 17 "log" 18 "math/rand" 19 "os" 20 "os/exec" 21 "path/filepath" 22 "regexp" 23 "runtime" 24 "strings" 25 "testing" 26 "time" 27 ) 28 29 var gopathInstallDir, gorootInstallDir, suffix string 30 31 // This is the smallest set of packages we can link into a shared 32 // library (runtime/cgo is built implicitly). 33 var minpkgs = []string{"runtime", "sync/atomic"} 34 var soname = "libruntime,sync-atomic.so" 35 36 // run runs a command and calls t.Errorf if it fails. 37 func run(t *testing.T, msg string, args ...string) { 38 c := exec.Command(args[0], args[1:]...) 39 if output, err := c.CombinedOutput(); err != nil { 40 t.Errorf("executing %s (%s) failed %s:\n%s", strings.Join(args, " "), msg, err, output) 41 } 42 } 43 44 // goCmd invokes the go tool with the installsuffix set up by TestMain. It calls 45 // t.Fatalf if the command fails. 46 func goCmd(t *testing.T, args ...string) { 47 newargs := []string{args[0], "-installsuffix=" + suffix} 48 if testing.Verbose() { 49 newargs = append(newargs, "-v") 50 } 51 newargs = append(newargs, args[1:]...) 52 c := exec.Command("go", newargs...) 53 var output []byte 54 var err error 55 if testing.Verbose() { 56 fmt.Printf("+ go %s\n", strings.Join(newargs, " ")) 57 c.Stdout = os.Stdout 58 c.Stderr = os.Stderr 59 err = c.Run() 60 } else { 61 output, err = c.CombinedOutput() 62 } 63 if err != nil { 64 if t != nil { 65 t.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, output) 66 } else { 67 log.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, output) 68 } 69 } 70 } 71 72 // TestMain calls testMain so that the latter can use defer (TestMain exits with os.Exit). 73 func testMain(m *testing.M) (int, error) { 74 // Because go install -buildmode=shared $standard_library_package always 75 // installs into $GOROOT, here are some gymnastics to come up with a unique 76 // installsuffix to use in this test that we can clean up afterwards. 77 myContext := build.Default 78 runtimeP, err := myContext.Import("runtime", ".", build.ImportComment) 79 if err != nil { 80 return 0, fmt.Errorf("import failed: %v", err) 81 } 82 for i := 0; i < 10000; i++ { 83 try := fmt.Sprintf("%s_%d_dynlink", runtimeP.PkgTargetRoot, rand.Int63()) 84 err = os.Mkdir(try, 0700) 85 if os.IsExist(err) { 86 continue 87 } 88 if err == nil { 89 gorootInstallDir = try 90 } 91 break 92 } 93 if err != nil { 94 return 0, fmt.Errorf("can't create temporary directory: %v", err) 95 } 96 if gorootInstallDir == "" { 97 return 0, errors.New("could not create temporary directory after 10000 tries") 98 } 99 if testing.Verbose() { 100 fmt.Printf("+ mkdir -p %s\n", gorootInstallDir) 101 } 102 defer os.RemoveAll(gorootInstallDir) 103 104 // Some tests need to edit the source in GOPATH, so copy this directory to a 105 // temporary directory and chdir to that. 106 scratchDir, err := ioutil.TempDir("", "testshared") 107 if err != nil { 108 return 0, fmt.Errorf("TempDir failed: %v", err) 109 } 110 if testing.Verbose() { 111 fmt.Printf("+ mkdir -p %s\n", scratchDir) 112 } 113 defer os.RemoveAll(scratchDir) 114 err = filepath.Walk(".", func(path string, info os.FileInfo, err error) error { 115 scratchPath := filepath.Join(scratchDir, path) 116 if info.IsDir() { 117 if path == "." { 118 return nil 119 } 120 if testing.Verbose() { 121 fmt.Printf("+ mkdir -p %s\n", scratchPath) 122 } 123 return os.Mkdir(scratchPath, info.Mode()) 124 } else { 125 fromBytes, err := ioutil.ReadFile(path) 126 if err != nil { 127 return err 128 } 129 if testing.Verbose() { 130 fmt.Printf("+ cp %s %s\n", path, scratchPath) 131 } 132 return ioutil.WriteFile(scratchPath, fromBytes, info.Mode()) 133 } 134 }) 135 if err != nil { 136 return 0, fmt.Errorf("walk failed: %v", err) 137 } 138 os.Setenv("GOPATH", scratchDir) 139 if testing.Verbose() { 140 fmt.Printf("+ export GOPATH=%s\n", scratchDir) 141 } 142 myContext.GOPATH = scratchDir 143 if testing.Verbose() { 144 fmt.Printf("+ cd %s\n", scratchDir) 145 } 146 os.Chdir(scratchDir) 147 148 // All tests depend on runtime being built into a shared library. Because 149 // that takes a few seconds, do it here and have all tests use the version 150 // built here. 151 suffix = strings.Split(filepath.Base(gorootInstallDir), "_")[2] 152 goCmd(nil, append([]string{"install", "-buildmode=shared"}, minpkgs...)...) 153 154 myContext.InstallSuffix = suffix + "_dynlink" 155 depP, err := myContext.Import("depBase", ".", build.ImportComment) 156 if err != nil { 157 return 0, fmt.Errorf("import failed: %v", err) 158 } 159 gopathInstallDir = depP.PkgTargetRoot 160 return m.Run(), nil 161 } 162 163 func TestMain(m *testing.M) { 164 // Some of the tests install binaries into a custom GOPATH. 165 // That won't work if GOBIN is set. 166 os.Unsetenv("GOBIN") 167 168 exitCode, err := testMain(m) 169 if err != nil { 170 log.Fatal(err) 171 } 172 os.Exit(exitCode) 173 } 174 175 // The shared library was built at the expected location. 176 func TestSOBuilt(t *testing.T) { 177 _, err := os.Stat(filepath.Join(gorootInstallDir, soname)) 178 if err != nil { 179 t.Error(err) 180 } 181 } 182 183 func hasDynTag(f *elf.File, tag elf.DynTag) bool { 184 ds := f.SectionByType(elf.SHT_DYNAMIC) 185 if ds == nil { 186 return false 187 } 188 d, err := ds.Data() 189 if err != nil { 190 return false 191 } 192 for len(d) > 0 { 193 var t elf.DynTag 194 switch f.Class { 195 case elf.ELFCLASS32: 196 t = elf.DynTag(f.ByteOrder.Uint32(d[0:4])) 197 d = d[8:] 198 case elf.ELFCLASS64: 199 t = elf.DynTag(f.ByteOrder.Uint64(d[0:8])) 200 d = d[16:] 201 } 202 if t == tag { 203 return true 204 } 205 } 206 return false 207 } 208 209 // The shared library does not have relocations against the text segment. 210 func TestNoTextrel(t *testing.T) { 211 sopath := filepath.Join(gorootInstallDir, soname) 212 f, err := elf.Open(sopath) 213 if err != nil { 214 t.Fatal("elf.Open failed: ", err) 215 } 216 defer f.Close() 217 if hasDynTag(f, elf.DT_TEXTREL) { 218 t.Errorf("%s has DT_TEXTREL set", soname) 219 } 220 } 221 222 // The shared library does not contain symbols called ".dup" 223 func TestNoDupSymbols(t *testing.T) { 224 sopath := filepath.Join(gorootInstallDir, soname) 225 f, err := elf.Open(sopath) 226 if err != nil { 227 t.Fatal("elf.Open failed: ", err) 228 } 229 defer f.Close() 230 syms, err := f.Symbols() 231 if err != nil { 232 t.Errorf("error reading symbols %v", err) 233 return 234 } 235 for _, s := range syms { 236 if s.Name == ".dup" { 237 t.Fatalf("%s contains symbol called .dup", sopath) 238 } 239 } 240 } 241 242 // The install command should have created a "shlibname" file for the 243 // listed packages (and runtime/cgo, and math on arm) indicating the 244 // name of the shared library containing it. 245 func TestShlibnameFiles(t *testing.T) { 246 pkgs := append([]string{}, minpkgs...) 247 pkgs = append(pkgs, "runtime/cgo") 248 if runtime.GOARCH == "arm" { 249 pkgs = append(pkgs, "math") 250 } 251 for _, pkg := range pkgs { 252 shlibnamefile := filepath.Join(gorootInstallDir, pkg+".shlibname") 253 contentsb, err := ioutil.ReadFile(shlibnamefile) 254 if err != nil { 255 t.Errorf("error reading shlibnamefile for %s: %v", pkg, err) 256 continue 257 } 258 contents := strings.TrimSpace(string(contentsb)) 259 if contents != soname { 260 t.Errorf("shlibnamefile for %s has wrong contents: %q", pkg, contents) 261 } 262 } 263 } 264 265 // Is a given offset into the file contained in a loaded segment? 266 func isOffsetLoaded(f *elf.File, offset uint64) bool { 267 for _, prog := range f.Progs { 268 if prog.Type == elf.PT_LOAD { 269 if prog.Off <= offset && offset < prog.Off+prog.Filesz { 270 return true 271 } 272 } 273 } 274 return false 275 } 276 277 func rnd(v int32, r int32) int32 { 278 if r <= 0 { 279 return v 280 } 281 v += r - 1 282 c := v % r 283 if c < 0 { 284 c += r 285 } 286 v -= c 287 return v 288 } 289 290 func readwithpad(r io.Reader, sz int32) ([]byte, error) { 291 data := make([]byte, rnd(sz, 4)) 292 _, err := io.ReadFull(r, data) 293 if err != nil { 294 return nil, err 295 } 296 data = data[:sz] 297 return data, nil 298 } 299 300 type note struct { 301 name string 302 tag int32 303 desc string 304 section *elf.Section 305 } 306 307 // Read all notes from f. As ELF section names are not supposed to be special, one 308 // looks for a particular note by scanning all SHT_NOTE sections looking for a note 309 // with a particular "name" and "tag". 310 func readNotes(f *elf.File) ([]*note, error) { 311 var notes []*note 312 for _, sect := range f.Sections { 313 if sect.Type != elf.SHT_NOTE { 314 continue 315 } 316 r := sect.Open() 317 for { 318 var namesize, descsize, tag int32 319 err := binary.Read(r, f.ByteOrder, &namesize) 320 if err != nil { 321 if err == io.EOF { 322 break 323 } 324 return nil, fmt.Errorf("read namesize failed: %v", err) 325 } 326 err = binary.Read(r, f.ByteOrder, &descsize) 327 if err != nil { 328 return nil, fmt.Errorf("read descsize failed: %v", err) 329 } 330 err = binary.Read(r, f.ByteOrder, &tag) 331 if err != nil { 332 return nil, fmt.Errorf("read type failed: %v", err) 333 } 334 name, err := readwithpad(r, namesize) 335 if err != nil { 336 return nil, fmt.Errorf("read name failed: %v", err) 337 } 338 desc, err := readwithpad(r, descsize) 339 if err != nil { 340 return nil, fmt.Errorf("read desc failed: %v", err) 341 } 342 notes = append(notes, ¬e{name: string(name), tag: tag, desc: string(desc), section: sect}) 343 } 344 } 345 return notes, nil 346 } 347 348 func dynStrings(t *testing.T, path string, flag elf.DynTag) []string { 349 f, err := elf.Open(path) 350 defer f.Close() 351 if err != nil { 352 t.Fatalf("elf.Open(%q) failed: %v", path, err) 353 } 354 dynstrings, err := f.DynString(flag) 355 if err != nil { 356 t.Fatalf("DynString(%s) failed on %s: %v", flag, path, err) 357 } 358 return dynstrings 359 } 360 361 func AssertIsLinkedToRegexp(t *testing.T, path string, re *regexp.Regexp) { 362 for _, dynstring := range dynStrings(t, path, elf.DT_NEEDED) { 363 if re.MatchString(dynstring) { 364 return 365 } 366 } 367 t.Errorf("%s is not linked to anything matching %v", path, re) 368 } 369 370 func AssertIsLinkedTo(t *testing.T, path, lib string) { 371 AssertIsLinkedToRegexp(t, path, regexp.MustCompile(regexp.QuoteMeta(lib))) 372 } 373 374 func AssertHasRPath(t *testing.T, path, dir string) { 375 for _, tag := range []elf.DynTag{elf.DT_RPATH, elf.DT_RUNPATH} { 376 for _, dynstring := range dynStrings(t, path, tag) { 377 for _, rpath := range strings.Split(dynstring, ":") { 378 if filepath.Clean(rpath) == filepath.Clean(dir) { 379 return 380 } 381 } 382 } 383 } 384 t.Errorf("%s does not have rpath %s", path, dir) 385 } 386 387 // Build a trivial program that links against the shared runtime and check it runs. 388 func TestTrivialExecutable(t *testing.T) { 389 goCmd(t, "install", "-linkshared", "trivial") 390 run(t, "trivial executable", "./bin/trivial") 391 AssertIsLinkedTo(t, "./bin/trivial", soname) 392 AssertHasRPath(t, "./bin/trivial", gorootInstallDir) 393 } 394 395 // Build a trivial program in PIE mode that links against the shared runtime and check it runs. 396 func TestTrivialExecutablePIE(t *testing.T) { 397 goCmd(t, "build", "-buildmode=pie", "-o", "trivial.pie", "-linkshared", "trivial") 398 run(t, "trivial executable", "./trivial.pie") 399 AssertIsLinkedTo(t, "./trivial.pie", soname) 400 AssertHasRPath(t, "./trivial.pie", gorootInstallDir) 401 } 402 403 // Build an executable that uses cgo linked against the shared runtime and check it 404 // runs. 405 func TestCgoExecutable(t *testing.T) { 406 goCmd(t, "install", "-linkshared", "execgo") 407 run(t, "cgo executable", "./bin/execgo") 408 } 409 410 func checkPIE(t *testing.T, name string) { 411 f, err := elf.Open(name) 412 if err != nil { 413 t.Fatal("elf.Open failed: ", err) 414 } 415 defer f.Close() 416 if f.Type != elf.ET_DYN { 417 t.Errorf("%s has type %v, want ET_DYN", name, f.Type) 418 } 419 if hasDynTag(f, elf.DT_TEXTREL) { 420 t.Errorf("%s has DT_TEXTREL set", name) 421 } 422 } 423 424 func TestTrivialPIE(t *testing.T) { 425 name := "trivial_pie" 426 goCmd(t, "build", "-buildmode=pie", "-o="+name, "trivial") 427 defer os.Remove(name) 428 run(t, name, "./"+name) 429 checkPIE(t, name) 430 } 431 432 func TestCgoPIE(t *testing.T) { 433 name := "cgo_pie" 434 goCmd(t, "build", "-buildmode=pie", "-o="+name, "execgo") 435 defer os.Remove(name) 436 run(t, name, "./"+name) 437 checkPIE(t, name) 438 } 439 440 // Build a GOPATH package into a shared library that links against the goroot runtime 441 // and an executable that links against both. 442 func TestGopathShlib(t *testing.T) { 443 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 444 AssertIsLinkedTo(t, filepath.Join(gopathInstallDir, "libdepBase.so"), soname) 445 goCmd(t, "install", "-linkshared", "exe") 446 AssertIsLinkedTo(t, "./bin/exe", soname) 447 AssertIsLinkedTo(t, "./bin/exe", "libdepBase.so") 448 AssertHasRPath(t, "./bin/exe", gorootInstallDir) 449 AssertHasRPath(t, "./bin/exe", gopathInstallDir) 450 // And check it runs. 451 run(t, "executable linked to GOPATH library", "./bin/exe") 452 } 453 454 // The shared library contains a note listing the packages it contains in a section 455 // that is not mapped into memory. 456 func testPkgListNote(t *testing.T, f *elf.File, note *note) { 457 if note.section.Flags != 0 { 458 t.Errorf("package list section has flags %v", note.section.Flags) 459 } 460 if isOffsetLoaded(f, note.section.Offset) { 461 t.Errorf("package list section contained in PT_LOAD segment") 462 } 463 if note.desc != "depBase\n" { 464 t.Errorf("incorrect package list %q", note.desc) 465 } 466 } 467 468 // The shared library contains a note containing the ABI hash that is mapped into 469 // memory and there is a local symbol called go.link.abihashbytes that points 16 470 // bytes into it. 471 func testABIHashNote(t *testing.T, f *elf.File, note *note) { 472 if note.section.Flags != elf.SHF_ALLOC { 473 t.Errorf("abi hash section has flags %v", note.section.Flags) 474 } 475 if !isOffsetLoaded(f, note.section.Offset) { 476 t.Errorf("abihash section not contained in PT_LOAD segment") 477 } 478 var hashbytes elf.Symbol 479 symbols, err := f.Symbols() 480 if err != nil { 481 t.Errorf("error reading symbols %v", err) 482 return 483 } 484 for _, sym := range symbols { 485 if sym.Name == "go.link.abihashbytes" { 486 hashbytes = sym 487 } 488 } 489 if hashbytes.Name == "" { 490 t.Errorf("no symbol called go.link.abihashbytes") 491 return 492 } 493 if elf.ST_BIND(hashbytes.Info) != elf.STB_LOCAL { 494 t.Errorf("%s has incorrect binding %v", hashbytes.Name, elf.ST_BIND(hashbytes.Info)) 495 } 496 if f.Sections[hashbytes.Section] != note.section { 497 t.Errorf("%s has incorrect section %v", hashbytes.Name, f.Sections[hashbytes.Section].Name) 498 } 499 if hashbytes.Value-note.section.Addr != 16 { 500 t.Errorf("%s has incorrect offset into section %d", hashbytes.Name, hashbytes.Value-note.section.Addr) 501 } 502 } 503 504 // A Go shared library contains a note indicating which other Go shared libraries it 505 // was linked against in an unmapped section. 506 func testDepsNote(t *testing.T, f *elf.File, note *note) { 507 if note.section.Flags != 0 { 508 t.Errorf("package list section has flags %v", note.section.Flags) 509 } 510 if isOffsetLoaded(f, note.section.Offset) { 511 t.Errorf("package list section contained in PT_LOAD segment") 512 } 513 // libdepBase.so just links against the lib containing the runtime. 514 if note.desc != soname { 515 t.Errorf("incorrect dependency list %q", note.desc) 516 } 517 } 518 519 // The shared library contains notes with defined contents; see above. 520 func TestNotes(t *testing.T) { 521 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 522 f, err := elf.Open(filepath.Join(gopathInstallDir, "libdepBase.so")) 523 if err != nil { 524 t.Fatal(err) 525 } 526 defer f.Close() 527 notes, err := readNotes(f) 528 if err != nil { 529 t.Fatal(err) 530 } 531 pkgListNoteFound := false 532 abiHashNoteFound := false 533 depsNoteFound := false 534 for _, note := range notes { 535 if note.name != "Go\x00\x00" { 536 continue 537 } 538 switch note.tag { 539 case 1: // ELF_NOTE_GOPKGLIST_TAG 540 if pkgListNoteFound { 541 t.Error("multiple package list notes") 542 } 543 testPkgListNote(t, f, note) 544 pkgListNoteFound = true 545 case 2: // ELF_NOTE_GOABIHASH_TAG 546 if abiHashNoteFound { 547 t.Error("multiple abi hash notes") 548 } 549 testABIHashNote(t, f, note) 550 abiHashNoteFound = true 551 case 3: // ELF_NOTE_GODEPS_TAG 552 if depsNoteFound { 553 t.Error("multiple abi hash notes") 554 } 555 testDepsNote(t, f, note) 556 depsNoteFound = true 557 } 558 } 559 if !pkgListNoteFound { 560 t.Error("package list note not found") 561 } 562 if !abiHashNoteFound { 563 t.Error("abi hash note not found") 564 } 565 if !depsNoteFound { 566 t.Error("deps note not found") 567 } 568 } 569 570 // Build a GOPATH package (depBase) into a shared library that links against the goroot 571 // runtime, another package (dep2) that links against the first, and and an 572 // executable that links against dep2. 573 func TestTwoGopathShlibs(t *testing.T) { 574 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 575 goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep2") 576 goCmd(t, "install", "-linkshared", "exe2") 577 run(t, "executable linked to GOPATH library", "./bin/exe2") 578 } 579 580 func TestThreeGopathShlibs(t *testing.T) { 581 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 582 goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep2") 583 goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep3") 584 goCmd(t, "install", "-linkshared", "exe3") 585 run(t, "executable linked to GOPATH library", "./bin/exe3") 586 } 587 588 // If gccgo is not available or not new enough call t.Skip. Otherwise, 589 // return a build.Context that is set up for gccgo. 590 func prepGccgo(t *testing.T) build.Context { 591 gccgoName := os.Getenv("GCCGO") 592 if gccgoName == "" { 593 gccgoName = "gccgo" 594 } 595 gccgoPath, err := exec.LookPath(gccgoName) 596 if err != nil { 597 t.Skip("gccgo not found") 598 } 599 cmd := exec.Command(gccgoPath, "-dumpversion") 600 output, err := cmd.CombinedOutput() 601 if err != nil { 602 t.Fatalf("%s -dumpversion failed: %v\n%s", gccgoPath, err, output) 603 } 604 if string(output) < "5" { 605 t.Skipf("gccgo too old (%s)", strings.TrimSpace(string(output))) 606 } 607 gccgoContext := build.Default 608 gccgoContext.InstallSuffix = suffix + "_fPIC" 609 gccgoContext.Compiler = "gccgo" 610 gccgoContext.GOPATH = os.Getenv("GOPATH") 611 return gccgoContext 612 } 613 614 // Build a GOPATH package into a shared library with gccgo and an executable that 615 // links against it. 616 func TestGoPathShlibGccgo(t *testing.T) { 617 gccgoContext := prepGccgo(t) 618 619 libgoRE := regexp.MustCompile("libgo.so.[0-9]+") 620 621 depP, err := gccgoContext.Import("depBase", ".", build.ImportComment) 622 if err != nil { 623 t.Fatalf("import failed: %v", err) 624 } 625 gccgoInstallDir := filepath.Join(depP.PkgTargetRoot, "shlibs") 626 goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "depBase") 627 AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdepBase.so"), libgoRE) 628 goCmd(t, "install", "-compiler=gccgo", "-linkshared", "exe") 629 AssertIsLinkedToRegexp(t, "./bin/exe", libgoRE) 630 AssertIsLinkedTo(t, "./bin/exe", "libdepBase.so") 631 AssertHasRPath(t, "./bin/exe", gccgoInstallDir) 632 // And check it runs. 633 run(t, "gccgo-built", "./bin/exe") 634 } 635 636 // The gccgo version of TestTwoGopathShlibs: build a GOPATH package into a shared 637 // library with gccgo, another GOPATH package that depends on the first and an 638 // executable that links the second library. 639 func TestTwoGopathShlibsGccgo(t *testing.T) { 640 gccgoContext := prepGccgo(t) 641 642 libgoRE := regexp.MustCompile("libgo.so.[0-9]+") 643 644 depP, err := gccgoContext.Import("depBase", ".", build.ImportComment) 645 if err != nil { 646 t.Fatalf("import failed: %v", err) 647 } 648 gccgoInstallDir := filepath.Join(depP.PkgTargetRoot, "shlibs") 649 goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "depBase") 650 goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "dep2") 651 goCmd(t, "install", "-compiler=gccgo", "-linkshared", "exe2") 652 653 AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdepBase.so"), libgoRE) 654 AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdep2.so"), libgoRE) 655 AssertIsLinkedTo(t, filepath.Join(gccgoInstallDir, "libdep2.so"), "libdepBase.so") 656 AssertIsLinkedToRegexp(t, "./bin/exe2", libgoRE) 657 AssertIsLinkedTo(t, "./bin/exe2", "libdep2") 658 AssertIsLinkedTo(t, "./bin/exe2", "libdepBase.so") 659 660 // And check it runs. 661 run(t, "gccgo-built", "./bin/exe2") 662 } 663 664 // Testing rebuilding of shared libraries when they are stale is a bit more 665 // complicated that it seems like it should be. First, we make everything "old": but 666 // only a few seconds old, or it might be older than gc (or the runtime source) and 667 // everything will get rebuilt. Then define a timestamp slightly newer than this 668 // time, which is what we set the mtime to of a file to cause it to be seen as new, 669 // and finally another slightly even newer one that we can compare files against to 670 // see if they have been rebuilt. 671 var oldTime = time.Now().Add(-9 * time.Second) 672 var nearlyNew = time.Now().Add(-6 * time.Second) 673 var stampTime = time.Now().Add(-3 * time.Second) 674 675 // resetFileStamps makes "everything" (bin, src, pkg from GOPATH and the 676 // test-specific parts of GOROOT) appear old. 677 func resetFileStamps() { 678 chtime := func(path string, info os.FileInfo, err error) error { 679 return os.Chtimes(path, oldTime, oldTime) 680 } 681 reset := func(path string) { 682 if err := filepath.Walk(path, chtime); err != nil { 683 log.Fatalf("resetFileStamps failed: %v", err) 684 } 685 686 } 687 reset("bin") 688 reset("pkg") 689 reset("src") 690 reset(gorootInstallDir) 691 } 692 693 // touch makes path newer than the "old" time stamp used by resetFileStamps. 694 func touch(path string) { 695 if err := os.Chtimes(path, nearlyNew, nearlyNew); err != nil { 696 log.Fatalf("os.Chtimes failed: %v", err) 697 } 698 } 699 700 // isNew returns if the path is newer than the time stamp used by touch. 701 func isNew(path string) bool { 702 fi, err := os.Stat(path) 703 if err != nil { 704 log.Fatalf("os.Stat failed: %v", err) 705 } 706 return fi.ModTime().After(stampTime) 707 } 708 709 // Fail unless path has been rebuilt (i.e. is newer than the time stamp used by 710 // isNew) 711 func AssertRebuilt(t *testing.T, msg, path string) { 712 if !isNew(path) { 713 t.Errorf("%s was not rebuilt (%s)", msg, path) 714 } 715 } 716 717 // Fail if path has been rebuilt (i.e. is newer than the time stamp used by isNew) 718 func AssertNotRebuilt(t *testing.T, msg, path string) { 719 if isNew(path) { 720 t.Errorf("%s was rebuilt (%s)", msg, path) 721 } 722 } 723 724 func TestRebuilding(t *testing.T) { 725 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 726 goCmd(t, "install", "-linkshared", "exe") 727 728 // If the source is newer than both the .a file and the .so, both are rebuilt. 729 resetFileStamps() 730 touch("src/depBase/dep.go") 731 goCmd(t, "install", "-linkshared", "exe") 732 AssertRebuilt(t, "new source", filepath.Join(gopathInstallDir, "depBase.a")) 733 AssertRebuilt(t, "new source", filepath.Join(gopathInstallDir, "libdepBase.so")) 734 735 // If the .a file is newer than the .so, the .so is rebuilt (but not the .a) 736 resetFileStamps() 737 touch(filepath.Join(gopathInstallDir, "depBase.a")) 738 goCmd(t, "install", "-linkshared", "exe") 739 AssertNotRebuilt(t, "new .a file", filepath.Join(gopathInstallDir, "depBase.a")) 740 AssertRebuilt(t, "new .a file", filepath.Join(gopathInstallDir, "libdepBase.so")) 741 } 742 743 func appendFile(path, content string) { 744 f, err := os.OpenFile(path, os.O_WRONLY|os.O_APPEND, 0660) 745 if err != nil { 746 log.Fatalf("os.OpenFile failed: %v", err) 747 } 748 defer func() { 749 err := f.Close() 750 if err != nil { 751 log.Fatalf("f.Close failed: %v", err) 752 } 753 }() 754 _, err = f.WriteString(content) 755 if err != nil { 756 log.Fatalf("f.WriteString failed: %v", err) 757 } 758 } 759 760 func TestABIChecking(t *testing.T) { 761 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 762 goCmd(t, "install", "-linkshared", "exe") 763 764 // If we make an ABI-breaking change to depBase and rebuild libp.so but not exe, 765 // exe will abort with a complaint on startup. 766 // This assumes adding an exported function breaks ABI, which is not true in 767 // some senses but suffices for the narrow definition of ABI compatibility the 768 // toolchain uses today. 769 resetFileStamps() 770 appendFile("src/depBase/dep.go", "func ABIBreak() {}\n") 771 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 772 c := exec.Command("./bin/exe") 773 output, err := c.CombinedOutput() 774 if err == nil { 775 t.Fatal("executing exe did not fail after ABI break") 776 } 777 scanner := bufio.NewScanner(bytes.NewReader(output)) 778 foundMsg := false 779 const wantLine = "abi mismatch detected between the executable and libdepBase.so" 780 for scanner.Scan() { 781 if scanner.Text() == wantLine { 782 foundMsg = true 783 break 784 } 785 } 786 if err = scanner.Err(); err != nil { 787 t.Errorf("scanner encountered error: %v", err) 788 } 789 if !foundMsg { 790 t.Fatalf("exe failed, but without line %q; got output:\n%s", wantLine, output) 791 } 792 793 // Rebuilding exe makes it work again. 794 goCmd(t, "install", "-linkshared", "exe") 795 run(t, "rebuilt exe", "./bin/exe") 796 797 // If we make a change which does not break ABI (such as adding an unexported 798 // function) and rebuild libdepBase.so, exe still works. 799 resetFileStamps() 800 appendFile("src/depBase/dep.go", "func noABIBreak() {}\n") 801 goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase") 802 run(t, "after non-ABI breaking change", "./bin/exe") 803 } 804 805 // If a package 'explicit' imports a package 'implicit', building 806 // 'explicit' into a shared library implicitly includes implicit in 807 // the shared library. Building an executable that imports both 808 // explicit and implicit builds the code from implicit into the 809 // executable rather than fetching it from the shared library. The 810 // link still succeeds and the executable still runs though. 811 func TestImplicitInclusion(t *testing.T) { 812 goCmd(t, "install", "-buildmode=shared", "-linkshared", "explicit") 813 goCmd(t, "install", "-linkshared", "implicitcmd") 814 run(t, "running executable linked against library that contains same package as it", "./bin/implicitcmd") 815 } 816 817 // Tests to make sure that the type fields of empty interfaces and itab 818 // fields of nonempty interfaces are unique even across modules, 819 // so that interface equality works correctly. 820 func TestInterface(t *testing.T) { 821 goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_a") 822 // Note: iface_i gets installed implicitly as a dependency of iface_a. 823 goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_b") 824 goCmd(t, "install", "-linkshared", "iface") 825 run(t, "running type/itab uniqueness tester", "./bin/iface") 826 }