Alexandre Lision | ddd731e | 2014-01-31 11:50:08 -0500 | [diff] [blame] | 1 | // Copyright (C) 1999-2005 Open Source Telecom Corporation. |
| 2 | // Copyright (C) 2006-2010 David Sugar, Tycho Softworks. |
| 3 | // |
| 4 | // This program is free software; you can redistribute it and/or modify |
| 5 | // it under the terms of the GNU General Public License as published by |
| 6 | // the Free Software Foundation; either version 2 of the License, or |
| 7 | // (at your option) any later version. |
| 8 | // |
| 9 | // This program is distributed in the hope that it will be useful, |
| 10 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | // GNU General Public License for more details. |
| 13 | // |
| 14 | // You should have received a copy of the GNU General Public License |
| 15 | // along with this program; if not, write to the Free Software |
| 16 | // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | // |
| 18 | // As a special exception, you may use this file as part of a free software |
| 19 | // library without restriction. Specifically, if other files instantiate |
| 20 | // templates or use macros or inline functions from this file, or you compile |
| 21 | // this file and link it with other files to produce an executable, this |
| 22 | // file does not by itself cause the resulting executable to be covered by |
| 23 | // the GNU General Public License. This exception does not however |
| 24 | // invalidate any other reasons why the executable file might be covered by |
| 25 | // the GNU General Public License. |
| 26 | // |
| 27 | // This exception applies only to the code released under the name GNU |
| 28 | // Common C++. If you copy code from other releases into a copy of GNU |
| 29 | // Common C++, as the General Public License permits, the exception does |
| 30 | // not apply to the code that you add in this way. To avoid misleading |
| 31 | // anyone as to the status of such modified files, you must delete |
| 32 | // this exception notice from them. |
| 33 | // |
| 34 | // If you write modifications of your own for GNU Common C++, it is your choice |
| 35 | // whether to permit this exception to apply to your modifications. |
| 36 | // If you do not wish that, delete this exception notice. |
| 37 | // |
| 38 | |
| 39 | /** |
| 40 | * @file commoncpp/process.h |
| 41 | * @short Process services. |
| 42 | **/ |
| 43 | |
| 44 | #ifndef COMMONCPP_PROCESS_H_ |
| 45 | #define COMMONCPP_PROCESS_H_ |
| 46 | |
| 47 | #ifndef COMMONCPP_CONFIG_H_ |
| 48 | #include <commoncpp/config.h> |
| 49 | #endif |
| 50 | |
| 51 | #ifndef COMMONCPP_THREAD_H_ |
| 52 | #include <commoncpp/thread.h> |
| 53 | #endif |
| 54 | |
| 55 | NAMESPACE_COMMONCPP |
| 56 | |
| 57 | /** |
| 58 | * A class for containing portable process related functions |
| 59 | * that help create portable code. These are typically |
| 60 | * referenced thru Process::xxx static member functions. |
| 61 | * Many of these members are used both for win32 and posix |
| 62 | * systems although some may be platform specific. |
| 63 | * |
| 64 | * @short Peocess wrapper class. |
| 65 | * @author David Sugar <dyfet@ostel.com> |
| 66 | */ |
| 67 | class __EXPORT Process |
| 68 | { |
| 69 | private: |
| 70 | static bool rtflag; |
| 71 | |
| 72 | public: |
| 73 | #ifndef _MSWINDOWS_ |
| 74 | typedef void (*Trap)(int); |
| 75 | |
| 76 | /** |
| 77 | * Detach current process into a daemon, posix |
| 78 | * only. Perhaps a similar method can be used |
| 79 | * for creating win32 "services"? |
| 80 | */ |
| 81 | static void detach(void); |
| 82 | |
| 83 | /** |
| 84 | * Attach the current process to another device |
| 85 | * or i/o session. It is deamonified and dissasociated |
| 86 | * with the prior parent process and controlling terminal. |
| 87 | * |
| 88 | * @param devname path to attach to. |
| 89 | */ |
| 90 | static void attach(const char *devname); |
| 91 | |
| 92 | /** |
| 93 | * Set a posix compliant signal handler. |
| 94 | * |
| 95 | * @return previous handler. |
| 96 | * @param signo signal no. |
| 97 | * @param handler trap handler. |
| 98 | */ |
| 99 | static Trap setPosixSignal(int signo, Trap handler); |
| 100 | |
| 101 | /** |
| 102 | * Set system call interuptable signal handler. |
| 103 | * |
| 104 | * #return previous handler. |
| 105 | * @param signo signal no. |
| 106 | * @param handler trap handler. |
| 107 | */ |
| 108 | static Trap setInterruptSignal(int signo, Trap handler); |
| 109 | #endif |
| 110 | /** |
| 111 | * Lock a process in memory. Ideally you should be deep enough |
| 112 | * where additional memallocs for functions will not kill you, |
| 113 | * or use false for future. |
| 114 | * |
| 115 | * @return true if successful. |
| 116 | * @param future pages as well... |
| 117 | */ |
| 118 | bool lock(bool future = true); |
| 119 | |
| 120 | /** |
| 121 | * Unlock process pages. |
| 122 | */ |
| 123 | void unlock(void); |
| 124 | |
| 125 | /** |
| 126 | * Spawn a process and wait for it's exit code. In win32 |
| 127 | * this is done with the spawn system call. In posix, |
| 128 | * this is done with a fork, an execvp, and a waitpid. |
| 129 | * |
| 130 | * @warning The implementation differences between posix and |
| 131 | * win32 systems may cause side effects. For instance, if you |
| 132 | * use atexit() and this spawn method, on posix systems the |
| 133 | * function set up with atexit() will be called when the |
| 134 | * parent process of the fork exits, which will not happen on |
| 135 | * Win32 systems. |
| 136 | * |
| 137 | * @return error code from process. |
| 138 | * @param exec name of executable. |
| 139 | * @param argv list of command arguments. |
| 140 | * @param wait for process to exit before return. |
| 141 | */ |
| 142 | static int spawn(const char *exec, const char **argv, bool wait = true); |
| 143 | |
| 144 | /** |
| 145 | * Get the exit status of another process, waiting for it |
| 146 | * to exit. |
| 147 | * |
| 148 | * @return exit code from process. |
| 149 | * @param pid process id. |
| 150 | */ |
| 151 | static int join(int pid); |
| 152 | |
| 153 | /** |
| 154 | * Cancel a running child process. |
| 155 | * |
| 156 | * @return 0 on success. |
| 157 | * @param pid process id. |
| 158 | * @param sig cancel signal to apply. |
| 159 | */ |
| 160 | static bool cancel(int pid, int sig = 0); |
| 161 | |
| 162 | /** |
| 163 | * Get system environment. |
| 164 | * |
| 165 | * @return system environ symbol. |
| 166 | * @param name of symbol. |
| 167 | */ |
| 168 | static const char *getEnv(const char *name); |
| 169 | |
| 170 | /** |
| 171 | * Set system environment in a standard manner. |
| 172 | * |
| 173 | * @param name of environment symbol to set. |
| 174 | * @param value of environment symbol. |
| 175 | * @param overwrite true if replace existing symbol. |
| 176 | */ |
| 177 | static void setEnv(const char *name, const char *value, bool overwrite); |
| 178 | |
| 179 | /** |
| 180 | * Get etc prefix path. |
| 181 | * |
| 182 | * @return etc prefix. |
| 183 | */ |
| 184 | static const char *getConfigDir(void); |
| 185 | |
| 186 | /** |
| 187 | * Get home directory. |
| 188 | * |
| 189 | * @return user home directory. |
| 190 | */ |
| 191 | static const char *getHomeDir(void); |
| 192 | |
| 193 | /** |
| 194 | * Get user name. |
| 195 | * |
| 196 | * @return user login id. |
| 197 | */ |
| 198 | static const char *getUser(void); |
| 199 | |
| 200 | /** |
| 201 | * Set user id by name. |
| 202 | * |
| 203 | * @return true if successful. |
| 204 | */ |
| 205 | static bool setUser(const char *id, bool grp = true); |
| 206 | |
| 207 | /** |
| 208 | * Set the effective group id by name. |
| 209 | * |
| 210 | * @return true if successful. |
| 211 | */ |
| 212 | static bool setGroup(const char *id); |
| 213 | |
| 214 | /** |
| 215 | * Return the effective operating system page size. |
| 216 | * |
| 217 | * @return system page size. |
| 218 | */ |
| 219 | static size_t getPageSize(void); |
| 220 | |
| 221 | /** |
| 222 | * Used to set process priority and optionally enable realtime. |
| 223 | */ |
| 224 | static void setPriority(int pri); |
| 225 | |
| 226 | /** |
| 227 | * Used to set process scheduling policy. |
| 228 | */ |
| 229 | static void setScheduler(const char *policy); |
| 230 | |
| 231 | /** |
| 232 | * Portable shortcut for setting realtime... |
| 233 | */ |
| 234 | static void setRealtime(int pri = 0); |
| 235 | |
| 236 | /** |
| 237 | * Return true if scheduler settable. |
| 238 | */ |
| 239 | static bool isScheduler(void); |
| 240 | |
| 241 | /** |
| 242 | * Return true if realtime scheduling. |
| 243 | */ |
| 244 | static inline bool isRealtime(void) |
| 245 | {return rtflag;}; |
| 246 | }; |
| 247 | |
| 248 | /** |
| 249 | * This class is used to create a "named" lock entity that can be used |
| 250 | * to control access to a resource between multiple processes. The |
| 251 | * posix implimentation uses a pidfile and the win32 version uses a |
| 252 | * globally visible mutex. |
| 253 | * |
| 254 | * @author David Sugar <dyfet@ostel.com> |
| 255 | * @short System-wide named lock |
| 256 | */ |
| 257 | class __EXPORT Lockfile |
| 258 | { |
| 259 | private: |
| 260 | #ifdef _MSWINDOWS_ |
| 261 | HANDLE _mutex; |
| 262 | bool _flagged; |
| 263 | #else |
| 264 | char *_path; |
| 265 | #endif |
| 266 | |
| 267 | public: |
| 268 | /** |
| 269 | * Create a lock under a known name. |
| 270 | * |
| 271 | * @param name of system-wide lock to create. |
| 272 | */ |
| 273 | Lockfile(const char *name); |
| 274 | |
| 275 | /** |
| 276 | * Create a new lock object that can be used to make locks. |
| 277 | */ |
| 278 | Lockfile(); |
| 279 | |
| 280 | /** |
| 281 | * Destroy the current lock and release it. |
| 282 | */ |
| 283 | ~Lockfile() |
| 284 | {unlock();}; |
| 285 | |
| 286 | /** |
| 287 | * Lock a system-wide name for this process. If the lock |
| 288 | * is successful, return true. If an existing lock was |
| 289 | * already acquired, release it first. |
| 290 | * |
| 291 | * @return true if lock successful. |
| 292 | * @param name system-wide lock to use. |
| 293 | */ |
| 294 | bool lock(const char *name); |
| 295 | |
| 296 | /** |
| 297 | * Release an acquired lock. |
| 298 | */ |
| 299 | void unlock(void); |
| 300 | |
| 301 | /** |
| 302 | * Flag if the current process has aqcuired a lock. |
| 303 | * |
| 304 | * @return true if we have the lock. |
| 305 | */ |
| 306 | bool isLocked(void); |
| 307 | }; |
| 308 | |
| 309 | END_NAMESPACE |
| 310 | |
| 311 | #endif |