sysmodule.c revision e0d7dae3b8008b5037df6cb212ca6efacf7a012d
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" /* !!! */ "\n\ 346Static objects:\n\ 347\n\ 348maxint -- the largest supported integer (the smallest is -maxint-1)\n\ 349builtin_module_names -- tuple of module names built into this intepreter\n\ 350version -- the version of this interpreter\n\ 351copyright -- copyright notice pertaining to this interpreter\n\ 352platform -- platform identifier\n\ 353executable -- pathname of this Python interpreter\n\ 354prefix -- prefix used to find the Python library\n\ 355exec_prefix -- prefix used to find the machine-specific Python library\n\ 356dllhandle -- [Windows only] integer handle of the Python DLL\n\ 357winver -- [Windows only] version number of the Python DLL\n\ 358__stdin__ -- the original stdin; don't use!\n\ 359__stdout__ -- the original stdout; don't use!\n\ 360__stderr__ -- the original stderr; don't use!\n\ 361\n\ 362Functions:\n\ 363\n\ 364exc_info() -- return thread-safe information about the current exception\n\ 365exit() -- exit the interpreter by raising SystemExit\n\ 366getrefcount() -- return the reference count for an object (plus one :-)\n\ 367setcheckinterval() -- control how often the interpreter checks for events\n\ 368setprofile() -- set the global profiling function\n\ 369settrace() -- set the global debug tracing function\n\ 370"; 371 372PyObject * 373_PySys_Init() 374{ 375 extern int fclose Py_PROTO((FILE *)); 376 PyObject *m, *v, *sysdict; 377 PyObject *sysin, *sysout, *syserr; 378 379 m = Py_InitModule3("sys", sys_methods, sys_doc); 380 sysdict = PyModule_GetDict(m); 381 382 sysin = PyFile_FromFile(stdin, "<stdin>", "r", NULL); 383 sysout = PyFile_FromFile(stdout, "<stdout>", "w", NULL); 384 syserr = PyFile_FromFile(stderr, "<stderr>", "w", NULL); 385 if (PyErr_Occurred()) 386 return NULL; 387 PyDict_SetItemString(sysdict, "stdin", sysin); 388 PyDict_SetItemString(sysdict, "stdout", sysout); 389 PyDict_SetItemString(sysdict, "stderr", syserr); 390 /* Make backup copies for cleanup */ 391 PyDict_SetItemString(sysdict, "__stdin__", sysin); 392 PyDict_SetItemString(sysdict, "__stdout__", sysout); 393 PyDict_SetItemString(sysdict, "__stderr__", syserr); 394 Py_XDECREF(sysin); 395 Py_XDECREF(sysout); 396 Py_XDECREF(syserr); 397 PyDict_SetItemString(sysdict, "version", 398 v = PyString_FromString(Py_GetVersion())); 399 PyDict_SetItemString(sysdict, "hexversion", 400 v = PyInt_FromLong(PY_VERSION_HEX)); 401 Py_XDECREF(v); 402 PyDict_SetItemString(sysdict, "copyright", 403 v = PyString_FromString(Py_GetCopyright())); 404 Py_XDECREF(v); 405 PyDict_SetItemString(sysdict, "platform", 406 v = PyString_FromString(Py_GetPlatform())); 407 Py_XDECREF(v); 408 PyDict_SetItemString(sysdict, "executable", 409 v = PyString_FromString(Py_GetProgramFullPath())); 410 Py_XDECREF(v); 411 PyDict_SetItemString(sysdict, "prefix", 412 v = PyString_FromString(Py_GetPrefix())); 413 Py_XDECREF(v); 414 PyDict_SetItemString(sysdict, "exec_prefix", 415 v = PyString_FromString(Py_GetExecPrefix())); 416 Py_XDECREF(v); 417 PyDict_SetItemString(sysdict, "maxint", 418 v = PyInt_FromLong(PyInt_GetMax())); 419 Py_XDECREF(v); 420 PyDict_SetItemString(sysdict, "builtin_module_names", 421 v = list_builtin_module_names()); 422 Py_XDECREF(v); 423#ifdef MS_COREDLL 424 PyDict_SetItemString(sysdict, "dllhandle", 425 v = PyInt_FromLong((int)PyWin_DLLhModule)); 426 Py_XDECREF(v); 427 PyDict_SetItemString(sysdict, "winver", 428 v = PyString_FromString(PyWin_DLLVersionString)); 429 Py_XDECREF(v); 430#endif 431 if (PyErr_Occurred()) 432 return NULL; 433 return m; 434} 435 436static PyObject * 437makepathobject(path, delim) 438 char *path; 439 int delim; 440{ 441 int i, n; 442 char *p; 443 PyObject *v, *w; 444 445 n = 1; 446 p = path; 447 while ((p = strchr(p, delim)) != NULL) { 448 n++; 449 p++; 450 } 451 v = PyList_New(n); 452 if (v == NULL) 453 return NULL; 454 for (i = 0; ; i++) { 455 p = strchr(path, delim); 456 if (p == NULL) 457 p = strchr(path, '\0'); /* End of string */ 458 w = PyString_FromStringAndSize(path, (int) (p - path)); 459 if (w == NULL) { 460 Py_DECREF(v); 461 return NULL; 462 } 463 PyList_SetItem(v, i, w); 464 if (*p == '\0') 465 break; 466 path = p+1; 467 } 468 return v; 469} 470 471void 472PySys_SetPath(path) 473 char *path; 474{ 475 PyObject *v; 476 if ((v = makepathobject(path, DELIM)) == NULL) 477 Py_FatalError("can't create sys.path"); 478 if (PySys_SetObject("path", v) != 0) 479 Py_FatalError("can't assign sys.path"); 480 Py_DECREF(v); 481} 482 483static PyObject * 484makeargvobject(argc, argv) 485 int argc; 486 char **argv; 487{ 488 PyObject *av; 489 if (argc <= 0 || argv == NULL) { 490 /* Ensure at least one (empty) argument is seen */ 491 static char *empty_argv[1] = {""}; 492 argv = empty_argv; 493 argc = 1; 494 } 495 av = PyList_New(argc); 496 if (av != NULL) { 497 int i; 498 for (i = 0; i < argc; i++) { 499 PyObject *v = PyString_FromString(argv[i]); 500 if (v == NULL) { 501 Py_DECREF(av); 502 av = NULL; 503 break; 504 } 505 PyList_SetItem(av, i, v); 506 } 507 } 508 return av; 509} 510 511void 512PySys_SetArgv(argc, argv) 513 int argc; 514 char **argv; 515{ 516 PyObject *av = makeargvobject(argc, argv); 517 PyObject *path = PySys_GetObject("path"); 518 if (av == NULL) 519 Py_FatalError("no mem for sys.argv"); 520 if (PySys_SetObject("argv", av) != 0) 521 Py_FatalError("can't assign sys.argv"); 522 if (path != NULL) { 523 char *argv0 = argv[0]; 524 char *p = NULL; 525 int n = 0; 526 PyObject *a; 527#ifdef HAVE_READLINK 528 char link[MAXPATHLEN+1]; 529 char argv0copy[2*MAXPATHLEN+1]; 530 int nr = 0; 531 if (argc > 0 && argv0 != NULL) 532 nr = readlink(argv0, link, MAXPATHLEN); 533 if (nr > 0) { 534 /* It's a symlink */ 535 link[nr] = '\0'; 536 if (link[0] == SEP) 537 argv0 = link; /* Link to absolute path */ 538 else if (strchr(link, SEP) == NULL) 539 ; /* Link without path */ 540 else { 541 /* Must join(dirname(argv0), link) */ 542 char *q = strrchr(argv0, SEP); 543 if (q == NULL) 544 argv0 = link; /* argv0 without path */ 545 else { 546 /* Must make a copy */ 547 strcpy(argv0copy, argv0); 548 q = strrchr(argv0copy, SEP); 549 strcpy(q+1, link); 550 argv0 = argv0copy; 551 } 552 } 553 } 554#endif /* HAVE_READLINK */ 555#if SEP == '\\' /* Special case for MS filename syntax */ 556 if (argc > 0 && argv0 != NULL) { 557 char *q; 558 p = strrchr(argv0, SEP); 559 /* Test for alternate separator */ 560 q = strrchr(p ? p : argv0, '/'); 561 if (q != NULL) 562 p = q; 563 if (p != NULL) { 564 n = p + 1 - argv0; 565 if (n > 1 && p[-1] != ':') 566 n--; /* Drop trailing separator */ 567 } 568 } 569#else /* All other filename syntaxes */ 570 if (argc > 0 && argv0 != NULL) 571 p = strrchr(argv0, SEP); 572 if (p != NULL) { 573 n = p + 1 - argv0; 574#if SEP == '/' /* Special case for Unix filename syntax */ 575 if (n > 1) 576 n--; /* Drop trailing separator */ 577#endif /* Unix */ 578 } 579#endif /* All others */ 580 a = PyString_FromStringAndSize(argv0, n); 581 if (a == NULL) 582 Py_FatalError("no mem for sys.path insertion"); 583 if (PyList_Insert(path, 0, a) < 0) 584 Py_FatalError("sys.path.insert(0) failed"); 585 Py_DECREF(a); 586 } 587 Py_DECREF(av); 588} 589 590 591/* APIs to write to sys.stdout or sys.stderr using a printf-like interface. 592 Adapted from code submitted by Just van Rossum. 593 594 PySys_WriteStdout(format, ...) 595 PySys_WriteStderr(format, ...) 596 597 The first function writes to sys.stdout; the second to sys.stderr. When 598 there is a problem, they write to the real (C level) stdout or stderr; 599 no exceptions are raised. 600 601 Both take a printf-style format string as their first argument followed 602 by a variable length argument list determined by the format string. 603 604 *** WARNING *** 605 606 The format should limit the total size of the formatted output string to 607 1000 bytes. In particular, this means that no unrestricted "%s" formats 608 should occur; these should be limited using "%.<N>s where <N> is a 609 decimal number calculated so that <N> plus the maximum size of other 610 formatted text does not exceed 1000 bytes. Also watch out for "%f", 611 which can print hundreds of digits for very large numbers. 612 613 */ 614 615static void 616mywrite(name, fp, format, va) 617 char *name; 618 FILE *fp; 619 const char *format; 620 va_list va; 621{ 622 PyObject *file; 623 PyObject *error_type, *error_value, *error_traceback; 624 625 PyErr_Fetch(&error_type, &error_value, &error_traceback); 626 file = PySys_GetObject(name); 627 if (file == NULL || PyFile_AsFile(file) == fp) 628 vfprintf(fp, format, va); 629 else { 630 char buffer[1001]; 631 if (vsprintf(buffer, format, va) >= sizeof(buffer)) 632 Py_FatalError("PySys_WriteStdout/err: buffer overrun"); 633 if (PyFile_WriteString(buffer, file) != 0) { 634 PyErr_Clear(); 635 fputs(buffer, fp); 636 } 637 } 638 PyErr_Restore(error_type, error_value, error_traceback); 639} 640 641void 642#ifdef HAVE_STDARG_PROTOTYPES 643PySys_WriteStdout(const char *format, ...) 644#else 645PySys_WriteStdout(va_alist) 646 va_dcl 647#endif 648{ 649 va_list va; 650 651#ifdef HAVE_STDARG_PROTOTYPES 652 va_start(va, format); 653#else 654 char *format; 655 va_start(va); 656 format = va_arg(va, char *); 657#endif 658 mywrite("stdout", stdout, format, va); 659 va_end(va); 660} 661 662void 663#ifdef HAVE_STDARG_PROTOTYPES 664PySys_WriteStderr(const char *format, ...) 665#else 666PySys_WriteStderr(va_alist) 667 va_dcl 668#endif 669{ 670 va_list va; 671 672#ifdef HAVE_STDARG_PROTOTYPES 673 va_start(va, format); 674#else 675 char *format; 676 va_start(va); 677 format = va_arg(va, char *); 678#endif 679 mywrite("stderr", stderr, format, va); 680 va_end(va); 681} 682