| |
| /* Readline interface for tokenizer.c and [raw_]input() in bltinmodule.c. |
| By default, or when stdin is not a tty device, we have a super |
| simple my_readline function using fgets. |
| Optionally, we can use the GNU readline library. |
| my_readline() has a different return value from GNU readline(): |
| - NULL if an interrupt occurred or if an error occurred |
| - a malloc'ed empty string if EOF was read |
| - a malloc'ed string ending in \n normally |
| */ |
| |
| #include "Python.h" |
| #include "pycore_pystate.h" // _PyThreadState_GET() |
| #ifdef MS_WINDOWS |
| # define WIN32_LEAN_AND_MEAN |
| # include "windows.h" |
| #endif /* MS_WINDOWS */ |
| |
| |
| PyThreadState* _PyOS_ReadlineTState = NULL; |
| |
| static PyThread_type_lock _PyOS_ReadlineLock = NULL; |
| |
| int (*PyOS_InputHook)(void) = NULL; |
| |
| /* This function restarts a fgets() after an EINTR error occurred |
| except if _PyOS_InterruptOccurred() returns true. */ |
| |
| static int |
| my_fgets(PyThreadState* tstate, char *buf, int len, FILE *fp) |
| { |
| #ifdef MS_WINDOWS |
| HANDLE handle; |
| _Py_BEGIN_SUPPRESS_IPH |
| handle = (HANDLE)_get_osfhandle(fileno(fp)); |
| _Py_END_SUPPRESS_IPH |
| |
| /* bpo-40826: fgets(fp) does crash if fileno(fp) is closed */ |
| if (handle == INVALID_HANDLE_VALUE) { |
| return -1; /* EOF */ |
| } |
| #endif |
| |
| while (1) { |
| if (PyOS_InputHook != NULL) { |
| (void)(PyOS_InputHook)(); |
| } |
| |
| errno = 0; |
| clearerr(fp); |
| char *p = fgets(buf, len, fp); |
| if (p != NULL) { |
| return 0; /* No error */ |
| } |
| int err = errno; |
| |
| #ifdef MS_WINDOWS |
| /* Ctrl-C anywhere on the line or Ctrl-Z if the only character |
| on a line will set ERROR_OPERATION_ABORTED. Under normal |
| circumstances Ctrl-C will also have caused the SIGINT handler |
| to fire which will have set the event object returned by |
| _PyOS_SigintEvent. This signal fires in another thread and |
| is not guaranteed to have occurred before this point in the |
| code. |
| |
| Therefore: check whether the event is set with a small timeout. |
| If it is, assume this is a Ctrl-C and reset the event. If it |
| isn't set assume that this is a Ctrl-Z on its own and drop |
| through to check for EOF. |
| */ |
| if (GetLastError()==ERROR_OPERATION_ABORTED) { |
| HANDLE hInterruptEvent = _PyOS_SigintEvent(); |
| switch (WaitForSingleObjectEx(hInterruptEvent, 10, FALSE)) { |
| case WAIT_OBJECT_0: |
| ResetEvent(hInterruptEvent); |
| return 1; /* Interrupt */ |
| case WAIT_FAILED: |
| return -2; /* Error */ |
| } |
| } |
| #endif /* MS_WINDOWS */ |
| |
| if (feof(fp)) { |
| clearerr(fp); |
| return -1; /* EOF */ |
| } |
| |
| #ifdef EINTR |
| if (err == EINTR) { |
| PyEval_RestoreThread(tstate); |
| int s = PyErr_CheckSignals(); |
| PyEval_SaveThread(); |
| |
| if (s < 0) { |
| return 1; |
| } |
| /* try again */ |
| continue; |
| } |
| #endif |
| |
| if (_PyOS_InterruptOccurred(tstate)) { |
| return 1; /* Interrupt */ |
| } |
| return -2; /* Error */ |
| } |
| /* NOTREACHED */ |
| } |
| |
| #ifdef MS_WINDOWS |
| /* Readline implementation using ReadConsoleW */ |
| |
| extern char _get_console_type(HANDLE handle); |
| |
| char * |
| _PyOS_WindowsConsoleReadline(PyThreadState *tstate, HANDLE hStdIn) |
| { |
| static wchar_t wbuf_local[1024 * 16]; |
| const DWORD chunk_size = 1024; |
| |
| DWORD n_read, total_read, wbuflen, u8len; |
| wchar_t *wbuf; |
| char *buf = NULL; |
| int err = 0; |
| |
| n_read = (DWORD)-1; |
| total_read = 0; |
| wbuf = wbuf_local; |
| wbuflen = sizeof(wbuf_local) / sizeof(wbuf_local[0]) - 1; |
| while (1) { |
| if (PyOS_InputHook != NULL) { |
| (void)(PyOS_InputHook)(); |
| } |
| if (!ReadConsoleW(hStdIn, &wbuf[total_read], wbuflen - total_read, &n_read, NULL)) { |
| err = GetLastError(); |
| goto exit; |
| } |
| if (n_read == (DWORD)-1 && (err = GetLastError()) == ERROR_OPERATION_ABORTED) { |
| break; |
| } |
| if (n_read == 0) { |
| int s; |
| err = GetLastError(); |
| if (err != ERROR_OPERATION_ABORTED) |
| goto exit; |
| err = 0; |
| HANDLE hInterruptEvent = _PyOS_SigintEvent(); |
| if (WaitForSingleObjectEx(hInterruptEvent, 100, FALSE) |
| == WAIT_OBJECT_0) { |
| ResetEvent(hInterruptEvent); |
| PyEval_RestoreThread(tstate); |
| s = PyErr_CheckSignals(); |
| PyEval_SaveThread(); |
| if (s < 0) { |
| goto exit; |
| } |
| } |
| break; |
| } |
| |
| total_read += n_read; |
| if (total_read == 0 || wbuf[total_read - 1] == L'\n') { |
| break; |
| } |
| wbuflen += chunk_size; |
| if (wbuf == wbuf_local) { |
| wbuf[total_read] = '\0'; |
| wbuf = (wchar_t*)PyMem_RawMalloc(wbuflen * sizeof(wchar_t)); |
| if (wbuf) { |
| wcscpy_s(wbuf, wbuflen, wbuf_local); |
| } |
| else { |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| goto exit; |
| } |
| } |
| else { |
| wchar_t *tmp = PyMem_RawRealloc(wbuf, wbuflen * sizeof(wchar_t)); |
| if (tmp == NULL) { |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| goto exit; |
| } |
| wbuf = tmp; |
| } |
| } |
| |
| if (wbuf[0] == '\x1a') { |
| buf = PyMem_RawMalloc(1); |
| if (buf) { |
| buf[0] = '\0'; |
| } |
| else { |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| } |
| goto exit; |
| } |
| |
| u8len = WideCharToMultiByte(CP_UTF8, 0, |
| wbuf, total_read, |
| NULL, 0, |
| NULL, NULL); |
| buf = PyMem_RawMalloc(u8len + 1); |
| if (buf == NULL) { |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| goto exit; |
| } |
| |
| u8len = WideCharToMultiByte(CP_UTF8, 0, |
| wbuf, total_read, |
| buf, u8len, |
| NULL, NULL); |
| buf[u8len] = '\0'; |
| |
| exit: |
| if (wbuf != wbuf_local) { |
| PyMem_RawFree(wbuf); |
| } |
| |
| if (err) { |
| PyEval_RestoreThread(tstate); |
| PyErr_SetFromWindowsErr(err); |
| PyEval_SaveThread(); |
| } |
| return buf; |
| } |
| |
| #endif |
| |
| |
| /* Readline implementation using fgets() */ |
| |
| char * |
| PyOS_StdioReadline(FILE *sys_stdin, FILE *sys_stdout, const char *prompt) |
| { |
| size_t n; |
| char *p, *pr; |
| PyThreadState *tstate = _PyOS_ReadlineTState; |
| assert(tstate != NULL); |
| |
| #ifdef MS_WINDOWS |
| if (!Py_LegacyWindowsStdioFlag && sys_stdin == stdin) { |
| HANDLE hStdIn, hStdErr; |
| |
| hStdIn = _Py_get_osfhandle_noraise(fileno(sys_stdin)); |
| hStdErr = _Py_get_osfhandle_noraise(fileno(stderr)); |
| |
| if (_get_console_type(hStdIn) == 'r') { |
| fflush(sys_stdout); |
| if (prompt) { |
| if (_get_console_type(hStdErr) == 'w') { |
| wchar_t *wbuf; |
| int wlen; |
| wlen = MultiByteToWideChar(CP_UTF8, 0, prompt, -1, |
| NULL, 0); |
| if (wlen) { |
| wbuf = PyMem_RawMalloc(wlen * sizeof(wchar_t)); |
| if (wbuf == NULL) { |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| return NULL; |
| } |
| wlen = MultiByteToWideChar(CP_UTF8, 0, prompt, -1, |
| wbuf, wlen); |
| if (wlen) { |
| DWORD n; |
| fflush(stderr); |
| /* wlen includes null terminator, so subtract 1 */ |
| WriteConsoleW(hStdErr, wbuf, wlen - 1, &n, NULL); |
| } |
| PyMem_RawFree(wbuf); |
| } |
| } else { |
| fprintf(stderr, "%s", prompt); |
| fflush(stderr); |
| } |
| } |
| clearerr(sys_stdin); |
| return _PyOS_WindowsConsoleReadline(tstate, hStdIn); |
| } |
| } |
| #endif |
| |
| fflush(sys_stdout); |
| if (prompt) { |
| fprintf(stderr, "%s", prompt); |
| } |
| fflush(stderr); |
| |
| n = 0; |
| p = NULL; |
| do { |
| size_t incr = (n > 0) ? n + 2 : 100; |
| if (incr > INT_MAX) { |
| PyMem_RawFree(p); |
| PyEval_RestoreThread(tstate); |
| PyErr_SetString(PyExc_OverflowError, "input line too long"); |
| PyEval_SaveThread(); |
| return NULL; |
| } |
| pr = (char *)PyMem_RawRealloc(p, n + incr); |
| if (pr == NULL) { |
| PyMem_RawFree(p); |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| return NULL; |
| } |
| p = pr; |
| int err = my_fgets(tstate, p + n, (int)incr, sys_stdin); |
| if (err == 1) { |
| // Interrupt |
| PyMem_RawFree(p); |
| return NULL; |
| } else if (err != 0) { |
| // EOF or error |
| p[n] = '\0'; |
| break; |
| } |
| n += strlen(p + n); |
| } while (p[n-1] != '\n'); |
| |
| pr = (char *)PyMem_RawRealloc(p, n+1); |
| if (pr == NULL) { |
| PyMem_RawFree(p); |
| PyEval_RestoreThread(tstate); |
| PyErr_NoMemory(); |
| PyEval_SaveThread(); |
| return NULL; |
| } |
| return pr; |
| } |
| |
| |
| /* By initializing this function pointer, systems embedding Python can |
| override the readline function. |
| |
| Note: Python expects in return a buffer allocated with PyMem_Malloc. */ |
| |
| char *(*PyOS_ReadlineFunctionPointer)(FILE *, FILE *, const char *) = NULL; |
| |
| |
| /* Interface used by tokenizer.c and bltinmodule.c */ |
| |
| char * |
| PyOS_Readline(FILE *sys_stdin, FILE *sys_stdout, const char *prompt) |
| { |
| char *rv, *res; |
| size_t len; |
| |
| PyThreadState *tstate = _PyThreadState_GET(); |
| if (_PyOS_ReadlineTState == tstate) { |
| PyErr_SetString(PyExc_RuntimeError, |
| "can't re-enter readline"); |
| return NULL; |
| } |
| |
| |
| if (PyOS_ReadlineFunctionPointer == NULL) { |
| PyOS_ReadlineFunctionPointer = PyOS_StdioReadline; |
| } |
| |
| if (_PyOS_ReadlineLock == NULL) { |
| _PyOS_ReadlineLock = PyThread_allocate_lock(); |
| if (_PyOS_ReadlineLock == NULL) { |
| PyErr_SetString(PyExc_MemoryError, "can't allocate lock"); |
| return NULL; |
| } |
| } |
| |
| _PyOS_ReadlineTState = tstate; |
| Py_BEGIN_ALLOW_THREADS |
| PyThread_acquire_lock(_PyOS_ReadlineLock, 1); |
| |
| /* This is needed to handle the unlikely case that the |
| * interpreter is in interactive mode *and* stdin/out are not |
| * a tty. This can happen, for example if python is run like |
| * this: python -i < test1.py |
| */ |
| if (!isatty (fileno (sys_stdin)) || !isatty (fileno (sys_stdout))) |
| rv = PyOS_StdioReadline (sys_stdin, sys_stdout, prompt); |
| else |
| rv = (*PyOS_ReadlineFunctionPointer)(sys_stdin, sys_stdout, |
| prompt); |
| Py_END_ALLOW_THREADS |
| |
| PyThread_release_lock(_PyOS_ReadlineLock); |
| |
| _PyOS_ReadlineTState = NULL; |
| |
| if (rv == NULL) |
| return NULL; |
| |
| len = strlen(rv) + 1; |
| res = PyMem_Malloc(len); |
| if (res != NULL) { |
| memcpy(res, rv, len); |
| } |
| else { |
| PyErr_NoMemory(); |
| } |
| PyMem_RawFree(rv); |
| |
| return res; |
| } |