Fix permissions handling (CVE-2010-0825).
[emacs.git] / nt / runemacs.c
blob4a3d4a9536d43d35651704ffe4afa10667c212bb
1 /* Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
2 Free Software Foundation, Inc.
4 This file is part of GNU Emacs.
6 GNU Emacs is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 GNU Emacs is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
21 Simple program to start Emacs with its console window hidden.
23 This program is provided purely for convenience, since most users will
24 use Emacs in windowing (GUI) mode, and will not want to have an extra
25 console window lying around. */
28 You may want to define this if you want to be able to install updated
29 emacs binaries even when other users are using the current version.
30 The problem with some file servers (notably Novell) is that an open
31 file cannot be overwritten, deleted, or even renamed. So if someone
32 is running emacs.exe already, you cannot install a newer version.
33 By defining CHOOSE_NEWEST_EXE, you can name your new emacs.exe
34 something else which matches "emacs*.exe", and runemacs will
35 automatically select the newest emacs executable in the bin directory.
36 (So you'll probably be able to delete the old version some hours/days
37 later).
40 /* #define CHOOSE_NEWEST_EXE */
42 #include <windows.h>
43 #include <string.h>
44 #include <malloc.h>
46 static void set_user_model_id ();
48 int WINAPI
49 WinMain (HINSTANCE hSelf, HINSTANCE hPrev, LPSTR cmdline, int nShow)
51 STARTUPINFO start;
52 SECURITY_ATTRIBUTES sec_attrs;
53 PROCESS_INFORMATION child;
54 int wait_for_child = FALSE;
55 DWORD priority_class = NORMAL_PRIORITY_CLASS;
56 DWORD ret_code = 0;
57 char *new_cmdline;
58 char *p;
59 char modname[MAX_PATH];
61 set_user_model_id ();
63 if (!GetModuleFileName (NULL, modname, MAX_PATH))
64 goto error;
65 if ((p = strrchr (modname, '\\')) == NULL)
66 goto error;
67 *p = 0;
69 new_cmdline = alloca (MAX_PATH + strlen (cmdline) + 3);
70 /* Quote executable name in case of spaces in the path. */
71 *new_cmdline = '"';
72 strcpy (new_cmdline + 1, modname);
74 #ifdef CHOOSE_NEWEST_EXE
76 /* Silly hack to allow new versions to be installed on
77 server even when current version is in use. */
79 char * best_name = alloca (MAX_PATH + 1);
80 FILETIME best_time = {0,0};
81 WIN32_FIND_DATA wfd;
82 HANDLE fh;
83 p = new_cmdline + strlen (new_cmdline);
84 strcpy (p, "\\emacs*.exe\" ");
85 fh = FindFirstFile (new_cmdline, &wfd);
86 if (fh == INVALID_HANDLE_VALUE)
87 goto error;
90 if (wfd.ftLastWriteTime.dwHighDateTime > best_time.dwHighDateTime
91 || (wfd.ftLastWriteTime.dwHighDateTime == best_time.dwHighDateTime
92 && wfd.ftLastWriteTime.dwLowDateTime > best_time.dwLowDateTime))
94 best_time = wfd.ftLastWriteTime;
95 strcpy (best_name, wfd.cFileName);
98 while (FindNextFile (fh, &wfd));
99 FindClose (fh);
100 *p++ = '\\';
101 strcpy (p, best_name);
102 strcat (p, " ");
104 #else
105 strcat (new_cmdline, "\\emacs.exe\" ");
106 #endif
108 /* Append original arguments if any; first look for arguments we
109 recognise (-wait, -high, and -low), and apply them ourselves. */
110 while (cmdline[0] == '-' || cmdline[0] == '/')
112 if (strncmp (cmdline+1, "wait", 4) == 0)
114 wait_for_child = TRUE;
115 cmdline += 5;
117 else if (strncmp (cmdline+1, "high", 4) == 0)
119 priority_class = HIGH_PRIORITY_CLASS;
120 cmdline += 5;
122 else if (strncmp (cmdline+1, "low", 3) == 0)
124 priority_class = IDLE_PRIORITY_CLASS;
125 cmdline += 4;
127 else
128 break;
129 /* Look for next argument. */
130 while (*++cmdline == ' ');
133 strcat (new_cmdline, cmdline);
135 /* Set emacs_dir variable if runemacs was in "%emacs_dir%\bin". */
136 if ((p = strrchr (modname, '\\')) && stricmp (p, "\\bin") == 0)
138 *p = 0;
139 for (p = modname; *p; p++)
140 if (*p == '\\') *p = '/';
141 SetEnvironmentVariable ("emacs_dir", modname);
144 memset (&start, 0, sizeof (start));
145 start.cb = sizeof (start);
146 start.dwFlags = STARTF_USESHOWWINDOW | STARTF_USECOUNTCHARS;
147 start.wShowWindow = SW_HIDE;
148 /* Ensure that we don't waste memory if the user has specified a huge
149 default screen buffer for command windows. */
150 start.dwXCountChars = 80;
151 start.dwYCountChars = 25;
153 sec_attrs.nLength = sizeof (sec_attrs);
154 sec_attrs.lpSecurityDescriptor = NULL;
155 sec_attrs.bInheritHandle = FALSE;
157 if (CreateProcess (NULL, new_cmdline, &sec_attrs, NULL, TRUE, priority_class,
158 NULL, NULL, &start, &child))
160 if (wait_for_child)
162 WaitForSingleObject (child.hProcess, INFINITE);
163 GetExitCodeProcess (child.hProcess, &ret_code);
165 CloseHandle (child.hThread);
166 CloseHandle (child.hProcess);
168 else
169 goto error;
170 return (int) ret_code;
172 error:
173 MessageBox (NULL, "Could not start Emacs.", "Error", MB_ICONSTOP);
174 return 1;
177 void set_user_model_id ()
179 HMODULE shell;
180 HRESULT (WINAPI * set_user_model) (wchar_t * id);
182 /* On Windows 7 and later, we need to set the user model ID
183 to associate emacsclient launched files with Emacs frames
184 in the UI. */
185 shell = LoadLibrary ("shell32.dll");
186 if (shell)
188 set_user_model
189 = (void *) GetProcAddress (shell,
190 "SetCurrentProcessExplicitAppUserModelID");
192 /* If the function is defined, then we are running on Windows 7
193 or newer, and the UI uses this to group related windows
194 together. Since emacs, runemacs, emacsclient are related, we
195 want them grouped even though the executables are different,
196 so we need to set a consistent ID between them. */
197 if (set_user_model)
198 set_user_model (L"GNU.Emacs");
200 FreeLibrary (shell);
204 /* arch-tag: 7e02df73-4df7-4aa0-baea-99c6d047a384
205 (do not change this comment) */