apr_thread_proc.h

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

 * @param new_attr The newly created procattr. 
 * @param cont The pool to use
 * @deffunc apr_status_t apr_procattr_create(apr_procattr_t **new_attr, apr_pool_t *cont)
 */
APR_DECLARE(apr_status_t) apr_procattr_create(apr_procattr_t **new_attr,
                                                  apr_pool_t *cont);

/**
 * Determine if any of stdin, stdout, or stderr should be linked to pipes 
 * when starting a child process.
 * @param attr The procattr we care about. 
 * @param in Should stdin be a pipe back to the parent?
 * @param out Should stdout be a pipe back to the parent?
 * @param err Should stderr be a pipe back to the parent?
 * @deffunc apr_status_t apr_procattr_io_set(apr_procattr_t *attr, apr_int32_t in, apr_int32_t out, apr_int32_t err)
 */
APR_DECLARE(apr_status_t) apr_procattr_io_set(apr_procattr_t *attr, 
                                             apr_int32_t in, apr_int32_t out,
                                             apr_int32_t err);

/**
 * Set the child_in and/or parent_in values to existing apr_file_t values.
 * @param attr The procattr we care about. 
 * @param child_in apr_file_t value to use as child_in. Must be a valid file.
 * @param parent_in apr_file_t value to use as parent_in. Must be a valid file.
 * @deffunc apr_status_t apr_procattr_child_in_set(struct apr_procattr_t *attr, apr_file_t *child_in, apr_file_t *parent_in)
 * @tip  This is NOT a required initializer function. This is
 *       useful if you have already opened a pipe (or multiple files)
 *       that you wish to use, perhaps persistently across multiple
 *       process invocations - such as a log file. You can save some 
 *       extra function calls by not creating your own pipe since this
 *       creates one in the process space for you.
 */
APR_DECLARE(apr_status_t) apr_procattr_child_in_set(struct apr_procattr_t *attr,
                                                  apr_file_t *child_in,
                                                  apr_file_t *parent_in);

/**
 * Set the child_out and parent_out values to existing apr_file_t values.
 * @param attr The procattr we care about. 
 * @param child_out apr_file_t value to use as child_out. Must be a valid file.
 * @param parent_out apr_file_t value to use as parent_out. Must be a valid file.
 * @deffunc apr_status_t apr_procattr_child_out_set(struct apr_procattr_t *attr, apr_file_t *child_out, apr_file_t *parent_out)
 * @tip This is NOT a required initializer function. This is
 *      useful if you have already opened a pipe (or multiple files)
 *      that you wish to use, perhaps persistently across multiple
 *      process invocations - such as a log file. 
 */
APR_DECLARE(apr_status_t) apr_procattr_child_out_set(struct apr_procattr_t *attr,
                                                   apr_file_t *child_out,
                                                   apr_file_t *parent_out);

/**
 * Set the child_err and parent_err values to existing apr_file_t values.
 * @param attr The procattr we care about. 
 * @param child_err apr_file_t value to use as child_err. Must be a valid file.
 * @param parent_err apr_file_t value to use as parent_err. Must be a valid file.
 * @deffunc apr_status_t apr_procattr_child_err_set(struct apr_procattr_t *attr, apr_file_t *child_err, apr_file_t *parent_err)
 * @tip This is NOT a required initializer function. This is
 *      useful if you have already opened a pipe (or multiple files)
 *      that you wish to use, perhaps persistently across multiple
 *      process invocations - such as a log file. 
 */
APR_DECLARE(apr_status_t) apr_procattr_child_err_set(struct apr_procattr_t *attr,
                                                   apr_file_t *child_err,
                                                   apr_file_t *parent_err);

/**
 * Set which directory the child process should start executing in.
 * @param attr The procattr we care about. 
 * @param dir Which dir to start in.  By default, this is the same dir as
 *            the parent currently resides in, when the createprocess call
 *            is made. 
 * @deffunc apr_status_t apr_procattr_dir_set(apr_procattr_t *attr, const char *dir)
 */
APR_DECLARE(apr_status_t) apr_procattr_dir_set(apr_procattr_t *attr, 
                                              const char *dir);

/**
 * Set what type of command the child process will call.
 * @param attr The procattr we care about. 
 * @param cmd The type of command.  One of:
 * <PRE>
 *            APR_SHELLCMD --  Shell script
 *            APR_PROGRAM  --  Executable program   (default) 
 * </PRE>
 * @deffunc apr_status_t apr_procattr_cmdtype_set(apr_procattr_t *attr, apr_cmdtype_e cmd)
 */
APR_DECLARE(apr_status_t) apr_procattr_cmdtype_set(apr_procattr_t *attr,
                                                  apr_cmdtype_e cmd);

/**
 * Determine if the chlid should start in detached state.
 * @param attr The procattr we care about. 
 * @param detach Should the child start in detached state?  Default is no. 
 * @deffunc apr_status_t apr_procattr_detach_set(apr_procattr_t *attr, apr_int32_t detach)
 */
APR_DECLARE(apr_status_t) apr_procattr_detach_set(apr_procattr_t *attr, 
                                                 apr_int32_t detach);

#if APR_HAVE_STRUCT_RLIMIT
/**
 * Set the Resource Utilization limits when starting a new process.
 * @param attr The procattr we care about. 
 * @param what Which limit to set, one of:
 * <PRE>
 *                 APR_LIMIT_CPU
 *                 APR_LIMIT_MEM
 *                 APR_LIMIT_NPROC
 * </PRE>
 * @param limit Value to set the limit to.
 * @deffunc apr_status_t apr_procattr_limit_set(apr_procattr_t *attr, apr_int32_t what, apr_int32_t what, struct rlimit *limit)
 */
APR_DECLARE(apr_status_t) apr_procattr_limit_set(apr_procattr_t *attr, 
                                                apr_int32_t what,
                                                struct rlimit *limit);
#endif

#if APR_HAS_FORK
/**
 * This is currently the only non-portable call in APR.  This executes 
 * a standard unix fork.
 * @param proc The resulting process handle. 
 * @param cont The pool to use. 
 * @deffunc apr_status_t apr_proc_fork(apr_proc_t *proc, apr_pool_t *cont)
 */
APR_DECLARE(apr_status_t) apr_proc_fork(apr_proc_t *proc, apr_pool_t *cont);
#endif

/**
 * Create a new process and execute a new program within that process.
 * @param new_proc The resulting process handle.
 * @param progname The program to run 
 * @param const_args the arguments to pass to the new program.  The first 
 *                   one should be the program name.
 * @param env The new environment table for the new process.  This 
 *            should be a list of NULL-terminated strings.
 * @param attr the procattr we should use to determine how to create the new
 *         process
 * @param cont The pool to use. 
 * @deffunc apr_status_t apr_proc_create(apr_proc_t *new_proc, const char *progname, const char * const *args, const char * const *env, apr_procattr_t *attr, apr_pool_t *cont)
 */
APR_DECLARE(apr_status_t) apr_proc_create(apr_proc_t *new_proc,
                                             const char *progname,
                                             const char * const *args,
                                             const char * const *env, 
                                             apr_procattr_t *attr, 
                                             apr_pool_t *cont);

/**
 * Wait for a child process to die
 * @param proc The process handle that corresponds to the desired child process 
 * @param waithow How should we wait.  One of:
 * <PRE>
 *            APR_WAIT   -- block until the child process dies.
 *            APR_NOWAIT -- return immediately regardless of if the 
 *                          child is dead or not.
 * </PRE>
 * @deffunc apr_status_t apr_proc_wait(apr_proc_t *proc, apr_wait_how_e waithow)
 * @tip The childs status is in the return code to this process.  It is one of:
 * <PRE>
 *            APR_CHILD_DONE     -- child is no longer running.
 *            APR_CHILD_NOTDONE  -- child is still running.
 * </PRE>
 */
APR_DECLARE(apr_status_t) apr_proc_wait(apr_proc_t *proc, 
                                        apr_wait_how_e waithow);

/**
 * Wait for any current child process to die and return information 
 * about that child.
 * @param proc Pointer to NULL on entry, will be filled out with child's 
 *             information 
 * @param status The returned exit status of the child, if a child process dies
 *               On platforms that don't support obtaining this information, 
 *               the status parameter will be returned as APR_ENOTIMPL.
 * @param waithow How should we wait.  One of:
 * <PRE>
 *            APR_WAIT   -- block until the child process dies.
 *            APR_NOWAIT -- return immediately regardless of if the 
 *                          child is dead or not.
 * </PRE>
 * @param p Pool to allocate child information out of.
 * @deffunc apr_status_t apr_proc_wait_all_procs(apr_proc_t *proc, apr_wait_t *status, apr_wait_how_e waithow, apr_pool_t *p)
 */
APR_DECLARE(apr_status_t) apr_proc_wait_all_procs(apr_proc_t *proc,
                                             apr_wait_t *status,
                                             apr_wait_how_e waithow,
                                             apr_pool_t *p);

/**
 * Detach the process from the controlling terminal.
 */
apr_status_t apr_proc_detach(void);

#if APR_HAS_OTHER_CHILD

/**
 * Register an other_child -- a child which must be kept track of so 
 * that the program knows when it has dies or disappeared.
 * @param pid pid is the pid of the child.
 * @param maintenance maintenance is a function that is invoked with a 
 *                    reason and the data pointer passed here.
 * @param data The data to pass to the maintenance function.
 * @param write_fd An fd that is probed for writing.  If it is ever unwritable
 *                 then the maintenance is invoked with reason 
 *                 OC_REASON_UNWRITABLE.
 * @param p The pool to use for allocating memory.
 * @deffunc void apr_proc_other_child_register(apr_proc_t *pid, void (*maintenance) (int reason, void *, int status), void *data, apr_file_t *write_fd, apr_pool_t *p)
 */
APR_DECLARE(void) apr_proc_other_child_register(apr_proc_t *pid, 
                                           void (*maintenance) (int reason, 
                                                                void *, 
                                                                int status),
                                           void *data, apr_file_t *write_fd,
                                           apr_pool_t *p);

/**
 * Stop watching the specified process.
 * @param data The data to pass to the maintenance function.  This is
 *             used to find the process to unregister.
 * @deffunc void apr_proc_other_child_unregister(void *data)
 * @tip Since this can be called by a maintenance function while we're
 *      scanning the other_children list, all scanners should protect 
 *      themself by loading ocr->next before calling any maintenance 
 *      function.
 */
APR_DECLARE(void) apr_proc_other_child_unregister(void *data);

/**
 * Check on the specified process.  If it is gone, call the maintenance 
 * function.
 * @param pid The process to check.
 * @param status The status to pass to the maintenance function.
 * @deffunc apr_status_t apr_proc_other_child_read(apr_proc_t *pid, int status);
 */
APR_DECLARE(apr_status_t) apr_proc_other_child_read(apr_proc_t *pid, int status);

/**
 * Loop through all registered other_children and call the appropriate 
 * maintenance function when necessary.
 * @deffunc void apr_proc_other_child_check();
 */
APR_DECLARE(void) apr_proc_other_child_check(void); 

/**
 * Ensure all the registered write_fds are still writable, otherwise 
 * invoke the maintenance functions as appropriate.
 * @deffunc void apr_proc_probe_writable_fds()
 */
APR_DECLARE(void) apr_proc_probe_writable_fds(void);

#endif /* APR_HAS_OTHER_CHILD */

/** 
 * Terminate a process.
 * @param proc The process to terminate.
 * @param sig How to kill the process.
 * @deffunc apr_status_t apr_proc_kill(apr_proc_t *proc, int sig)
 */
APR_DECLARE(apr_status_t) apr_proc_kill(apr_proc_t *proc, int sig);

/**
 * Register a process to be killed when a pool dies.
 * @param a The pool to use to define the processes lifetime 
 * @param pid The process to register
 * @param how How to kill the process, one of:
 * <PRE>
 *         kill_never   	   -- process is never sent any signals
 *         kill_always 	   -- process is sent SIGKILL on apr_pool_t cleanup	
 *         kill_after_timeout -- SIGTERM, wait 3 seconds, SIGKILL
 *         just_wait          -- wait forever for the process to complete
 *         kill_only_once     -- send SIGTERM and then wait
 * </PRE>
 * @deffunc void apr_pool_note_subprocess(struct apr_pool_t *a, apr_proc_t *pid, enum kill_conditions how)
 */
APR_DECLARE(void) apr_pool_note_subprocess(apr_pool_t *a, apr_proc_t *pid,
                                      enum kill_conditions how);

#if APR_HAS_THREADS && !defined(OS2) && APR_HAVE_SIGWAIT

/**
 * Setup the process for a single thread to be used for all signal handling.
 * @warn This must be called before any threads are created
 * @deffunc apr_status_t apr_setup_signal_thread(void)
 */
APR_DECLARE(apr_status_t) apr_setup_signal_thread(void);

/**
 * Create a thread that will listen for signals.  The thread will loop
 * forever, calling a provided function whenever it receives a signal.  That
 * functions should return 1 if the signal has been handled, 0 otherwise.
 * @param td The newly created thread
 * @param tattr The threadattr to use when creating the thread
 * @param signal_handler The function to call when a signal is received
 * @param p The pool to use when creating the thread
 * @deffunc apr_status_t apr_create_signal_thread(apr_thread_t **td, apr_threadattr_t *tattr, int (*signal_handler)(int signum), apr_pool_t *p)
 */
APR_DECLARE(apr_status_t) apr_create_signal_thread(apr_thread_t **td,
                                                   apr_threadattr_t *tattr,
                                              int (*signal_handler)(int signum),
                                                   apr_pool_t *p);
#endif /* APR_HAS_THREADS */

#ifdef __cplusplus
}
#endif

#endif  /* ! APR_THREAD_PROC_H */