sysmodule.c revision a71b5f4e1d39cda3d78a20a1c41056d362c56630
1/*********************************************************** 2Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam, 3The Netherlands. 4 5 All Rights Reserved 6 7Permission to use, copy, modify, and distribute this software and its 8documentation for any purpose and without fee is hereby granted, 9provided that the above copyright notice appear in all copies and that 10both that copyright notice and this permission notice appear in 11supporting documentation, and that the names of Stichting Mathematisch 12Centrum or CWI or Corporation for National Research Initiatives or 13CNRI not be used in advertising or publicity pertaining to 14distribution of the software without specific, written prior 15permission. 16 17While CWI is the initial source for this software, a modified version 18is made available by the Corporation for National Research Initiatives 19(CNRI) at the Internet address ftp://ftp.python.org. 20 21STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH 22REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF 23MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH 24CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL 25DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 26PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 27TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 28PERFORMANCE OF THIS SOFTWARE. 29 30******************************************************************/ 31 32/* System module */ 33 34/* 35Various bits of information used by the interpreter are collected in 36module 'sys'. 37Function member: 38- exit(sts): raise SystemExit 39Data members: 40- stdin, stdout, stderr: standard file objects 41- modules: the table of modules (dictionary) 42- path: module search path (list of strings) 43- argv: script arguments (list of strings) 44- ps1, ps2: optional primary and secondary prompts (strings) 45*/ 46 47#include "Python.h" 48 49#include "osdefs.h" 50 51#ifdef HAVE_UNISTD_H 52#include <unistd.h> 53#endif 54 55#ifdef MS_COREDLL 56extern void *PyWin_DLLhModule; 57/* A string loaded from the DLL at startup: */ 58extern const char *PyWin_DLLVersionString; 59#endif 60 61PyObject * 62PySys_GetObject(name) 63 char *name; 64{ 65 PyThreadState *tstate = PyThreadState_Get(); 66 PyObject *sd = tstate->interp->sysdict; 67 return PyDict_GetItemString(sd, name); 68} 69 70FILE * 71PySys_GetFile(name, def) 72 char *name; 73 FILE *def; 74{ 75 FILE *fp = NULL; 76 PyObject *v = PySys_GetObject(name); 77 if (v != NULL && PyFile_Check(v)) 78 fp = PyFile_AsFile(v); 79 if (fp == NULL) 80 fp = def; 81 return fp; 82} 83 84int 85PySys_SetObject(name, v) 86 char *name; 87 PyObject *v; 88{ 89 PyThreadState *tstate = PyThreadState_Get(); 90 PyObject *sd = tstate->interp->sysdict; 91 if (v == NULL) { 92 if (PyDict_GetItemString(sd, name) == NULL) 93 return 0; 94 else 95 return PyDict_DelItemString(sd, name); 96 } 97 else 98 return PyDict_SetItemString(sd, name, v); 99} 100 101static PyObject * 102sys_exc_info(self, args) 103 PyObject *self; 104 PyObject *args; 105{ 106 PyThreadState *tstate; 107 if (!PyArg_Parse(args, "")) 108 return NULL; 109 tstate = PyThreadState_Get(); 110 return Py_BuildValue( 111 "(OOO)", 112 tstate->exc_type != NULL ? tstate->exc_type : Py_None, 113 tstate->exc_value != NULL ? tstate->exc_value : Py_None, 114 tstate->exc_traceback != NULL ? 115 tstate->exc_traceback : Py_None); 116} 117 118static char exc_info_doc[] = 119"exc_info() -> (type, value, traceback)\n\ 120\n\ 121Return information about the exception that is currently being handled.\n\ 122This should be called from inside an except clause only."; 123 124static PyObject * 125sys_exit(self, args) 126 PyObject *self; 127 PyObject *args; 128{ 129 /* Raise SystemExit so callers may catch it or clean up. */ 130 PyErr_SetObject(PyExc_SystemExit, args); 131 return NULL; 132} 133 134static char exit_doc[] = 135"exit([status])\n\ 136\n\ 137Exit the interpreter by raising SystemExit(status).\n\ 138If the status is omitted or None, it defaults to zero (i.e., success).\n\ 139If the status numeric, it will be used as the system exit status.\n\ 140If it is another kind of object, it will be printed and the system\n\ 141exit status will be one (i.e., failure)."; 142 143static PyObject * 144sys_settrace(self, args) 145 PyObject *self; 146 PyObject *args; 147{ 148 PyThreadState *tstate = PyThreadState_Get(); 149 if (args == Py_None) 150 args = NULL; 151 else 152 Py_XINCREF(args); 153 Py_XDECREF(tstate->sys_tracefunc); 154 tstate->sys_tracefunc = args; 155 Py_INCREF(Py_None); 156 return Py_None; 157} 158 159static char settrace_doc[] = 160"settrace(function)\n\ 161\n\ 162Set the global debug tracing function. It will be called on each\n\ 163function call. See the debugger chapter in the library manual."; 164 165static PyObject * 166sys_setprofile(self, args) 167 PyObject *self; 168 PyObject *args; 169{ 170 PyThreadState *tstate = PyThreadState_Get(); 171 if (args == Py_None) 172 args = NULL; 173 else 174 Py_XINCREF(args); 175 Py_XDECREF(tstate->sys_profilefunc); 176 tstate->sys_profilefunc = args; 177 Py_INCREF(Py_None); 178 return Py_None; 179} 180 181static char setprofile_doc[] = 182"setprofile(function)\n\ 183\n\ 184Set the profiling function. It will be called on each function call\n\ 185and return. See the profiler chapter in the library manual."; 186 187static PyObject * 188sys_setcheckinterval(self, args) 189 PyObject *self; 190 PyObject *args; 191{ 192 PyThreadState *tstate = PyThreadState_Get(); 193 if (!PyArg_ParseTuple(args, "i", &tstate->interp->checkinterval)) 194 return NULL; 195 Py_INCREF(Py_None); 196 return Py_None; 197} 198 199static char setcheckinterval_doc[] = 200"setcheckinterval(n)\n\ 201\n\ 202Tell the Python interpreter to check for asynchronous events every\n\ 203n instructions. This also affects how often thread switches occur."; 204 205#ifdef USE_MALLOPT 206/* Link with -lmalloc (or -lmpc) on an SGI */ 207#include <malloc.h> 208 209static PyObject * 210sys_mdebug(self, args) 211 PyObject *self; 212 PyObject *args; 213{ 214 int flag; 215 if (!PyArg_Parse(args, "i", &flag)) 216 return NULL; 217 mallopt(M_DEBUG, flag); 218 Py_INCREF(Py_None); 219 return Py_None; 220} 221#endif /* USE_MALLOPT */ 222 223static PyObject * 224sys_getrefcount(self, args) 225 PyObject *self; 226 PyObject *args; 227{ 228 PyObject *arg; 229 if (!PyArg_Parse(args, "O", &arg)) 230 return NULL; 231 return PyInt_FromLong((long) arg->ob_refcnt); 232} 233 234static char getrefcount_doc[] = 235"getrefcount(object) -> integer\n\ 236\n\ 237Return the current reference count for the object. This includes the\n\ 238temporary reference in the argument list, so it is at least 2."; 239 240#ifdef COUNT_ALLOCS 241static PyObject * 242sys_getcounts(self, args) 243 PyObject *self, *args; 244{ 245 extern PyObject *get_counts Py_PROTO((void)); 246 247 if (!PyArg_Parse(args, "")) 248 return NULL; 249 return get_counts(); 250} 251#endif 252 253#ifdef Py_TRACE_REFS 254/* Defined in objects.c because it uses static globals if that file */ 255extern PyObject *_Py_GetObjects Py_PROTO((PyObject *, PyObject *)); 256#endif 257 258#ifdef DYNAMIC_EXECUTION_PROFILE 259/* Defined in ceval.c because it uses static globals if that file */ 260extern PyObject *_Py_GetDXProfile Py_PROTO((PyObject *, PyObject *)); 261#endif 262 263static PyMethodDef sys_methods[] = { 264 /* Might as well keep this in alphabetic order */ 265 {"exc_info", sys_exc_info, 0, exc_info_doc}, 266 {"exit", sys_exit, 0, exit_doc}, 267#ifdef COUNT_ALLOCS 268 {"getcounts", sys_getcounts, 0}, 269#endif 270#ifdef DYNAMIC_EXECUTION_PROFILE 271 {"getdxp", _Py_GetDXProfile, 1}, 272#endif 273#ifdef Py_TRACE_REFS 274 {"getobjects", _Py_GetObjects, 1}, 275#endif 276 {"getrefcount", sys_getrefcount, 0, getrefcount_doc}, 277#ifdef USE_MALLOPT 278 {"mdebug", sys_mdebug, 0}, 279#endif 280 {"setcheckinterval", sys_setcheckinterval, 1, setcheckinterval_doc}, 281 {"setprofile", sys_setprofile, 0, setprofile_doc}, 282 {"settrace", sys_settrace, 0, settrace_doc}, 283 {NULL, NULL} /* sentinel */ 284}; 285 286static PyObject * 287list_builtin_module_names() 288{ 289 PyObject *list = PyList_New(0); 290 int i; 291 if (list == NULL) 292 return NULL; 293 for (i = 0; PyImport_Inittab[i].name != NULL; i++) { 294 PyObject *name = PyString_FromString( 295 PyImport_Inittab[i].name); 296 if (name == NULL) 297 break; 298 PyList_Append(list, name); 299 Py_DECREF(name); 300 } 301 if (PyList_Sort(list) != 0) { 302 Py_DECREF(list); 303 list = NULL; 304 } 305 if (list) { 306 PyObject *v = PyList_AsTuple(list); 307 Py_DECREF(list); 308 list = v; 309 } 310 return list; 311} 312 313/* XXX This doc string is too long to be a single string literal in VC++ 5.0. 314 Two literals concatenated works just fine. If you have a K&R compiler 315 or other abomination that however *does* understand longer strings, 316 get rid of the !!! comment in the middle and the quotes that surround it. */ 317static char sys_doc[] = 318"This module provides access to some objects used or maintained by the\n\ 319interpreter and to functions that interact strongly with the interpreter.\n\ 320\n\ 321Dynamic objects:\n\ 322\n\ 323argv -- command line arguments; argv[0] is the script pathname if known\n\ 324path -- module search path; path[0] is the script directory, else ''\n\ 325modules -- dictionary of loaded modules\n\ 326exitfunc -- you may set this to a function to be called when Python exits\n\ 327\n\ 328stdin -- standard input file object; used by raw_input() and input()\n\ 329stdout -- standard output file object; used by the print statement\n\ 330stderr -- standard error object; used for error messages\n\ 331 By assigning another file object (or an object that behaves like a file)\n\ 332 to one of these, it is possible to redirect all of the interpreter's I/O.\n\ 333\n\ 334last_type -- type of last uncaught exception\n\ 335last_value -- value of last uncaught exception\n\ 336last_traceback -- traceback of last uncaught exception\n\ 337 These three are only available in an interactive session after a\n\ 338 traceback has been printed.\n\ 339\n\ 340exc_type -- type of exception currently being handled\n\ 341exc_value -- value of exception currently being handled\n\ 342exc_traceback -- traceback of exception currently being handled\n\ 343 The function exc_info() should be used instead of these three,\n\ 344 because it is thread-safe.\n\ 345" 346#ifndef MS_WIN16 347/* Concatenating string here */ 348"\n\ 349Static objects:\n\ 350\n\ 351maxint -- the largest supported integer (the smallest is -maxint-1)\n\ 352builtin_module_names -- tuple of module names built into this intepreter\n\ 353version -- the version of this interpreter\n\ 354copyright -- copyright notice pertaining to this interpreter\n\ 355platform -- platform identifier\n\ 356executable -- pathname of this Python interpreter\n\ 357prefix -- prefix used to find the Python library\n\ 358exec_prefix -- prefix used to find the machine-specific Python library\n\ 359dllhandle -- [Windows only] integer handle of the Python DLL\n\ 360winver -- [Windows only] version number of the Python DLL\n\ 361__stdin__ -- the original stdin; don't use!\n\ 362__stdout__ -- the original stdout; don't use!\n\ 363__stderr__ -- the original stderr; don't use!\n\ 364\n\ 365Functions:\n\ 366\n\ 367exc_info() -- return thread-safe information about the current exception\n\ 368exit() -- exit the interpreter by raising SystemExit\n\ 369getrefcount() -- return the reference count for an object (plus one :-)\n\ 370setcheckinterval() -- control how often the interpreter checks for events\n\ 371setprofile() -- set the global profiling function\n\ 372settrace() -- set the global debug tracing function\n\ 373"; 374#endif 375 376PyObject * 377_PySys_Init() 378{ 379 extern int fclose Py_PROTO((FILE *)); 380 PyObject *m, *v, *sysdict; 381 PyObject *sysin, *sysout, *syserr; 382 383 m = Py_InitModule3("sys", sys_methods, sys_doc); 384 sysdict = PyModule_GetDict(m); 385 386 sysin = PyFile_FromFile(stdin, "<stdin>", "r", NULL); 387 sysout = PyFile_FromFile(stdout, "<stdout>", "w", NULL); 388 syserr = PyFile_FromFile(stderr, "<stderr>", "w", NULL); 389 if (PyErr_Occurred()) 390 return NULL; 391 PyDict_SetItemString(sysdict, "stdin", sysin); 392 PyDict_SetItemString(sysdict, "stdout", sysout); 393 PyDict_SetItemString(sysdict, "stderr", syserr); 394 /* Make backup copies for cleanup */ 395 PyDict_SetItemString(sysdict, "__stdin__", sysin); 396 PyDict_SetItemString(sysdict, "__stdout__", sysout); 397 PyDict_SetItemString(sysdict, "__stderr__", syserr); 398 Py_XDECREF(sysin); 399 Py_XDECREF(sysout); 400 Py_XDECREF(syserr); 401 PyDict_SetItemString(sysdict, "version", 402 v = PyString_FromString(Py_GetVersion())); 403 PyDict_SetItemString(sysdict, "hexversion", 404 v = PyInt_FromLong(PY_VERSION_HEX)); 405 Py_XDECREF(v); 406 PyDict_SetItemString(sysdict, "copyright", 407 v = PyString_FromString(Py_GetCopyright())); 408 Py_XDECREF(v); 409 PyDict_SetItemString(sysdict, "platform", 410 v = PyString_FromString(Py_GetPlatform())); 411 Py_XDECREF(v); 412 PyDict_SetItemString(sysdict, "executable", 413 v = PyString_FromString(Py_GetProgramFullPath())); 414 Py_XDECREF(v); 415 PyDict_SetItemString(sysdict, "prefix", 416 v = PyString_FromString(Py_GetPrefix())); 417 Py_XDECREF(v); 418 PyDict_SetItemString(sysdict, "exec_prefix", 419 v = PyString_FromString(Py_GetExecPrefix())); 420 Py_XDECREF(v); 421 PyDict_SetItemString(sysdict, "maxint", 422 v = PyInt_FromLong(PyInt_GetMax())); 423 Py_XDECREF(v); 424 PyDict_SetItemString(sysdict, "builtin_module_names", 425 v = list_builtin_module_names()); 426 Py_XDECREF(v); 427#ifdef MS_COREDLL 428 PyDict_SetItemString(sysdict, "dllhandle", 429 v = PyInt_FromLong((int)PyWin_DLLhModule)); 430 Py_XDECREF(v); 431 PyDict_SetItemString(sysdict, "winver", 432 v = PyString_FromString(PyWin_DLLVersionString)); 433 Py_XDECREF(v); 434#endif 435 if (PyErr_Occurred()) 436 return NULL; 437 return m; 438} 439 440static PyObject * 441makepathobject(path, delim) 442 char *path; 443 int delim; 444{ 445 int i, n; 446 char *p; 447 PyObject *v, *w; 448 449 n = 1; 450 p = path; 451 while ((p = strchr(p, delim)) != NULL) { 452 n++; 453 p++; 454 } 455 v = PyList_New(n); 456 if (v == NULL) 457 return NULL; 458 for (i = 0; ; i++) { 459 p = strchr(path, delim); 460 if (p == NULL) 461 p = strchr(path, '\0'); /* End of string */ 462 w = PyString_FromStringAndSize(path, (int) (p - path)); 463 if (w == NULL) { 464 Py_DECREF(v); 465 return NULL; 466 } 467 PyList_SetItem(v, i, w); 468 if (*p == '\0') 469 break; 470 path = p+1; 471 } 472 return v; 473} 474 475void 476PySys_SetPath(path) 477 char *path; 478{ 479 PyObject *v; 480 if ((v = makepathobject(path, DELIM)) == NULL) 481 Py_FatalError("can't create sys.path"); 482 if (PySys_SetObject("path", v) != 0) 483 Py_FatalError("can't assign sys.path"); 484 Py_DECREF(v); 485} 486 487static PyObject * 488makeargvobject(argc, argv) 489 int argc; 490 char **argv; 491{ 492 PyObject *av; 493 if (argc <= 0 || argv == NULL) { 494 /* Ensure at least one (empty) argument is seen */ 495 static char *empty_argv[1] = {""}; 496 argv = empty_argv; 497 argc = 1; 498 } 499 av = PyList_New(argc); 500 if (av != NULL) { 501 int i; 502 for (i = 0; i < argc; i++) { 503 PyObject *v = PyString_FromString(argv[i]); 504 if (v == NULL) { 505 Py_DECREF(av); 506 av = NULL; 507 break; 508 } 509 PyList_SetItem(av, i, v); 510 } 511 } 512 return av; 513} 514 515void 516PySys_SetArgv(argc, argv) 517 int argc; 518 char **argv; 519{ 520 PyObject *av = makeargvobject(argc, argv); 521 PyObject *path = PySys_GetObject("path"); 522 if (av == NULL) 523 Py_FatalError("no mem for sys.argv"); 524 if (PySys_SetObject("argv", av) != 0) 525 Py_FatalError("can't assign sys.argv"); 526 if (path != NULL) { 527 char *argv0 = argv[0]; 528 char *p = NULL; 529 int n = 0; 530 PyObject *a; 531#ifdef HAVE_READLINK 532 char link[MAXPATHLEN+1]; 533 char argv0copy[2*MAXPATHLEN+1]; 534 int nr = 0; 535 if (argc > 0 && argv0 != NULL) 536 nr = readlink(argv0, link, MAXPATHLEN); 537 if (nr > 0) { 538 /* It's a symlink */ 539 link[nr] = '\0'; 540 if (link[0] == SEP) 541 argv0 = link; /* Link to absolute path */ 542 else if (strchr(link, SEP) == NULL) 543 ; /* Link without path */ 544 else { 545 /* Must join(dirname(argv0), link) */ 546 char *q = strrchr(argv0, SEP); 547 if (q == NULL) 548 argv0 = link; /* argv0 without path */ 549 else { 550 /* Must make a copy */ 551 strcpy(argv0copy, argv0); 552 q = strrchr(argv0copy, SEP); 553 strcpy(q+1, link); 554 argv0 = argv0copy; 555 } 556 } 557 } 558#endif /* HAVE_READLINK */ 559#if SEP == '\\' /* Special case for MS filename syntax */ 560 if (argc > 0 && argv0 != NULL) { 561 char *q; 562 p = strrchr(argv0, SEP); 563 /* Test for alternate separator */ 564 q = strrchr(p ? p : argv0, '/'); 565 if (q != NULL) 566 p = q; 567 if (p != NULL) { 568 n = p + 1 - argv0; 569 if (n > 1 && p[-1] != ':') 570 n--; /* Drop trailing separator */ 571 } 572 } 573#else /* All other filename syntaxes */ 574 if (argc > 0 && argv0 != NULL) 575 p = strrchr(argv0, SEP); 576 if (p != NULL) { 577 n = p + 1 - argv0; 578#if SEP == '/' /* Special case for Unix filename syntax */ 579 if (n > 1) 580 n--; /* Drop trailing separator */ 581#endif /* Unix */ 582 } 583#endif /* All others */ 584 a = PyString_FromStringAndSize(argv0, n); 585 if (a == NULL) 586 Py_FatalError("no mem for sys.path insertion"); 587 if (PyList_Insert(path, 0, a) < 0) 588 Py_FatalError("sys.path.insert(0) failed"); 589 Py_DECREF(a); 590 } 591 Py_DECREF(av); 592} 593 594 595/* APIs to write to sys.stdout or sys.stderr using a printf-like interface. 596 Adapted from code submitted by Just van Rossum. 597 598 PySys_WriteStdout(format, ...) 599 PySys_WriteStderr(format, ...) 600 601 The first function writes to sys.stdout; the second to sys.stderr. When 602 there is a problem, they write to the real (C level) stdout or stderr; 603 no exceptions are raised. 604 605 Both take a printf-style format string as their first argument followed 606 by a variable length argument list determined by the format string. 607 608 *** WARNING *** 609 610 The format should limit the total size of the formatted output string to 611 1000 bytes. In particular, this means that no unrestricted "%s" formats 612 should occur; these should be limited using "%.<N>s where <N> is a 613 decimal number calculated so that <N> plus the maximum size of other 614 formatted text does not exceed 1000 bytes. Also watch out for "%f", 615 which can print hundreds of digits for very large numbers. 616 617 */ 618 619static void 620mywrite(name, fp, format, va) 621 char *name; 622 FILE *fp; 623 const char *format; 624 va_list va; 625{ 626 PyObject *file; 627 PyObject *error_type, *error_value, *error_traceback; 628 629 PyErr_Fetch(&error_type, &error_value, &error_traceback); 630 file = PySys_GetObject(name); 631 if (file == NULL || PyFile_AsFile(file) == fp) 632 vfprintf(fp, format, va); 633 else { 634 char buffer[1001]; 635 if (vsprintf(buffer, format, va) >= sizeof(buffer)) 636 Py_FatalError("PySys_WriteStdout/err: buffer overrun"); 637 if (PyFile_WriteString(buffer, file) != 0) { 638 PyErr_Clear(); 639 fputs(buffer, fp); 640 } 641 } 642 PyErr_Restore(error_type, error_value, error_traceback); 643} 644 645void 646#ifdef HAVE_STDARG_PROTOTYPES 647PySys_WriteStdout(const char *format, ...) 648#else 649PySys_WriteStdout(va_alist) 650 va_dcl 651#endif 652{ 653 va_list va; 654 655#ifdef HAVE_STDARG_PROTOTYPES 656 va_start(va, format); 657#else 658 char *format; 659 va_start(va); 660 format = va_arg(va, char *); 661#endif 662 mywrite("stdout", stdout, format, va); 663 va_end(va); 664} 665 666void 667#ifdef HAVE_STDARG_PROTOTYPES 668PySys_WriteStderr(const char *format, ...) 669#else 670PySys_WriteStderr(va_alist) 671 va_dcl 672#endif 673{ 674 va_list va; 675 676#ifdef HAVE_STDARG_PROTOTYPES 677 va_start(va, format); 678#else 679 char *format; 680 va_start(va); 681 format = va_arg(va, char *); 682#endif 683 mywrite("stderr", stderr, format, va); 684 va_end(va); 685} 686