| 1 | /* Readline support for Python. |
| 2 | |
| 3 | Copyright (C) 2012-2014 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "python-internal.h" |
| 22 | #include "exceptions.h" |
| 23 | #include "top.h" |
| 24 | #include "cli/cli-utils.h" |
| 25 | #include <string.h> |
| 26 | |
| 27 | #include <stddef.h> |
| 28 | |
| 29 | /* Readline function suitable for PyOS_ReadlineFunctionPointer, which |
| 30 | is used for Python's interactive parser and raw_input. In both |
| 31 | cases, sys_stdin and sys_stdout are always stdin and stdout |
| 32 | respectively, as far as I can tell; they are ignored and |
| 33 | command_line_input is used instead. */ |
| 34 | |
| 35 | static char * |
| 36 | gdbpy_readline_wrapper (FILE *sys_stdin, FILE *sys_stdout, |
| 37 | char *prompt) |
| 38 | { |
| 39 | int n; |
| 40 | char *p = NULL, *q; |
| 41 | volatile struct gdb_exception except; |
| 42 | |
| 43 | TRY_CATCH (except, RETURN_MASK_ALL) |
| 44 | p = command_line_input (prompt, 0, "python"); |
| 45 | |
| 46 | /* Detect user interrupt (Ctrl-C). */ |
| 47 | if (except.reason == RETURN_QUIT) |
| 48 | return NULL; |
| 49 | |
| 50 | /* Handle errors by raising Python exceptions. */ |
| 51 | if (except.reason < 0) |
| 52 | { |
| 53 | /* The thread state is nulled during gdbpy_readline_wrapper, |
| 54 | with the original value saved in the following undocumented |
| 55 | variable (see Python's Parser/myreadline.c and |
| 56 | Modules/readline.c). */ |
| 57 | PyEval_RestoreThread (_PyOS_ReadlineTState); |
| 58 | gdbpy_convert_exception (except); |
| 59 | PyEval_SaveThread (); |
| 60 | return NULL; |
| 61 | } |
| 62 | |
| 63 | /* Detect EOF (Ctrl-D). */ |
| 64 | if (p == NULL) |
| 65 | { |
| 66 | q = PyMem_Malloc (1); |
| 67 | if (q != NULL) |
| 68 | q[0] = '\0'; |
| 69 | return q; |
| 70 | } |
| 71 | |
| 72 | n = strlen (p); |
| 73 | |
| 74 | /* Copy the line to Python and return. */ |
| 75 | q = PyMem_Malloc (n + 2); |
| 76 | if (q != NULL) |
| 77 | { |
| 78 | strncpy (q, p, n); |
| 79 | q[n] = '\n'; |
| 80 | q[n + 1] = '\0'; |
| 81 | } |
| 82 | return q; |
| 83 | } |
| 84 | |
| 85 | /* Initialize Python readline support. */ |
| 86 | |
| 87 | void |
| 88 | gdbpy_initialize_gdb_readline (void) |
| 89 | { |
| 90 | /* Python's readline module conflicts with GDB's use of readline |
| 91 | since readline is not reentrant. Ideally, a reentrant wrapper to |
| 92 | GDB's readline should be implemented to replace Python's readline |
| 93 | and prevent conflicts. For now, this file implements a |
| 94 | sys.meta_path finder that simply fails to import the readline |
| 95 | module. */ |
| 96 | if (PyRun_SimpleString ("\ |
| 97 | import sys\n\ |
| 98 | \n\ |
| 99 | class GdbRemoveReadlineFinder:\n\ |
| 100 | def find_module(self, fullname, path=None):\n\ |
| 101 | if fullname == 'readline' and path is None:\n\ |
| 102 | return self\n\ |
| 103 | return None\n\ |
| 104 | \n\ |
| 105 | def load_module(self, fullname):\n\ |
| 106 | raise ImportError('readline module disabled under GDB')\n\ |
| 107 | \n\ |
| 108 | sys.meta_path.append(GdbRemoveReadlineFinder())\n\ |
| 109 | ") == 0) |
| 110 | PyOS_ReadlineFunctionPointer = gdbpy_readline_wrapper; |
| 111 | } |
| 112 | |