/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef APR_THREAD_PROC_H
#define APR_THREAD_PROC_H
/**
* @file apr_thread_proc.h
* @brief APR Thread and Process Library
*/
#include "apr.h"
#include "apr_file_io.h"
#include "apr_pools.h"
#include "apr_errno.h"
#if APR_HAVE_STRUCT_RLIMIT
#include <sys/time.h>
#include <sys/resource.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/**
* @defgroup apr_thread_proc Threads and Process Functions
* @ingroup APR
* @{
*/
typedef enum {
APR_SHELLCMD, /**< use the shell to invoke the program */
APR_PROGRAM, /**< invoke the program directly, no copied env */
APR_PROGRAM_ENV, /**< invoke the program, replicating our environment */
APR_PROGRAM_PATH, /**< find program on PATH, use our environment */
APR_SHELLCMD_ENV /**< use the shell to invoke the program,
* replicating our environment
*/
} apr_cmdtype_e;
typedef enum {
APR_WAIT, /**< wait for the specified process to finish */
APR_NOWAIT /**< do not wait -- just see if it has finished */
} apr_wait_how_e;
/* I am specifically calling out the values so that the macros below make
* more sense. Yes, I know I don't need to, but I am hoping this makes what
* I am doing more clear. If you want to add more reasons to exit, continue
* to use bitmasks.
*/
typedef enum {
APR_PROC_EXIT = 1, /**< process exited normally */
APR_PROC_SIGNAL = 2, /**< process exited due to a signal */
APR_PROC_SIGNAL_CORE = 4 /**< process exited and dumped a core file */
} apr_exit_why_e;
/** did we exit the process */
#define APR_PROC_CHECK_EXIT(x) (x & APR_PROC_EXIT)
/** did we get a signal */
#define APR_PROC_CHECK_SIGNALED(x) (x & APR_PROC_SIGNAL)
/** did we get core */
#define APR_PROC_CHECK_CORE_DUMP(x) (x & APR_PROC_SIGNAL_CORE)
/** @see apr_procattr_io_set */
#define APR_NO_PIPE 0
/** @see apr_procattr_io_set and apr_file_pipe_create_ex */
#define APR_FULL_BLOCK 1
/** @see apr_procattr_io_set and apr_file_pipe_create_ex */
#define APR_FULL_NONBLOCK 2
/** @see apr_procattr_io_set */
#define APR_PARENT_BLOCK 3
/** @see apr_procattr_io_set */
#define APR_CHILD_BLOCK 4
/** @see apr_procattr_io_set */
#define APR_NO_FILE 8
/** @see apr_file_pipe_create_ex */
#define APR_READ_BLOCK 3
/** @see apr_file_pipe_create_ex */
#define APR_WRITE_BLOCK 4
/** @see apr_procattr_io_set
* @note Win32 only effective with version 1.2.12, portably introduced in 1.3.0
*/
#define APR_NO_FILE 8
/** @see apr_procattr_limit_set */
#define APR_LIMIT_CPU 0
/** @see apr_procattr_limit_set */
#define APR_LIMIT_MEM 1
/** @see apr_procattr_limit_set */
#define APR_LIMIT_NPROC 2
/** @see apr_procattr_limit_set */
#define APR_LIMIT_NOFILE 3
/**
* @defgroup APR_OC Other Child Flags
* @{
*/
#define APR_OC_REASON_DEATH 0 /**< child has died, caller must call
* unregister still */
#define APR_OC_REASON_UNWRITABLE 1 /**< write_fd is unwritable */
#define APR_OC_REASON_RESTART 2 /**< a restart is occurring, perform
* any necessary cleanup (including
* sending a special signal to child)
*/
#define APR_OC_REASON_UNREGISTER 3 /**< unregister has been called, do
* whatever is necessary (including
* kill the child) */
#define APR_OC_REASON_LOST 4 /**< somehow the child exited without
* us knowing ... buggy os? */
#define APR_OC_REASON_RUNNING 5 /**< a health check is occurring,
* for most maintainence functions
* this is a no-op.
*/
/** @} */
/** The APR process type */
typedef struct apr_proc_t {
/** The process ID */
pid_t pid;
/** Parent's side of pipe to child's stdin */
apr_file_t *in;
/** Parent's side of pipe to child's stdout */
apr_file_t *out;
/** Parent's side of pipe to child's stdouterr */
apr_file_t *err;
#if APR_HAS_PROC_INVOKED || defined(DOXYGEN)
/** Diagnositics/debugging string of the command invoked for
* this process [only present if APR_HAS_PROC_INVOKED is true]
* @remark Only enabled on Win32 by default.
* @bug This should either always or never be present in release
* builds - since it breaks binary compatibility. We may enable
* it always in APR 1.0 yet leave it undefined in most cases.
*/
char *invoked;
#endif
#if defined(WIN32) || defined(DOXYGEN)
/** (Win32 only) Creator's handle granting access to the process
* @remark This handle is closed and reset to NULL in every case
* corresponding to a waitpid() on Unix which returns the exit status.
* Therefore Win32 correspond's to Unix's zombie reaping characteristics
* and avoids potential handle leaks.
*/
HANDLE hproc;
#endif
} apr_proc_t;
/**
* The prototype for APR child errfn functions. (See the description
* of apr_procattr_child_errfn_set() for more information.)
* It is passed the following parameters:
* @param pool Pool associated with the apr_proc_t. If your child
* error function needs user data, associate it with this
* pool.
* @param err APR error code describing the error
* @param description Text description of type of processing which failed
*/
typedef void (apr_child_errfn_t)(apr_pool_t *proc, apr_status_t err,
const char *description);
/** Opaque Thread structure. */
typedef struct apr_thread_t apr_thread_t;
/** Opaque Thread attributes structure. */
typedef struct apr_threadattr_t apr_threadattr_t;
/** Opaque Process attributes structure. */
typedef struct apr_procattr_t apr_procattr_t;
/** Opaque control variable for one-time atomic variables. */
typedef struct apr_thread_once_t apr_thread_once_t;
/** Opaque thread private address space. */
typedef struct apr_threadkey_t apr_threadkey_t;
/** Opaque record of child process. */
typedef struct apr_other_child_rec_t apr_other_child_rec_t;
/**
* The prototype for any APR thread worker functions.
*/
typedef void *(APR_THREAD_FUNC *apr_thread_start_t)(apr_thread_t*, void*);
typedef enum {
APR_KILL_NEVER, /**< process is never killed (i.e., never sent
* any signals), but it will be reaped if it exits
* before the pool is cleaned up */
APR_KILL_ALWAYS, /**< process is sent SIGKILL on apr_pool_t cleanup */
APR_KILL_AFTER_TIMEOUT, /**< SIGTERM, wait 3 seconds, SIGKILL */
APR_JUST_WAIT, /**< wait forever for the process to complete */
APR_KILL_ONLY_ONCE /**< send SIGTERM and then wait */
} apr_kill_conditions_e;
/* Thread Function definitions */
#if APR_HAS_THREADS
/**
* Create and initialize a new threadattr variable
* @param new_attr The newly created threadattr.
* @param cont The pool to use
*/
APR_DECLARE(apr_status_t) apr_threadattr_create(apr_threadattr_t **new_attr,
apr_pool_t *cont);
/**
* Set if newly created threads should be created in detached state.
* @param attr The threadattr to affect
* @param on Non-zero if detached threads should be created.
*/
APR_DECLARE(apr_status_t) apr_threadattr_detach_set(apr_threadattr_t *attr,
apr_int32_t on);
/**
* Get the detach state for this threadattr.
* @param attr The threadattr to reference
* @return APR_DETACH if threads are to be detached, or APR_NOTDETACH
* if threads are to be joinable.
*/
APR_DECLARE(apr_status_t) apr_threadattr_detach_get(apr_threadattr_t *attr);
/**
* Set the stack size of newly created threads.
* @param attr The threadattr to affect
* @param stacksize The stack size in bytes
*/
APR_DECLARE(apr_status_t) apr_threadattr_stacksize_set(apr_threadattr_t *attr,
apr_size_t stacksize);
/**
* Set the stack guard area size of newly created threads.
* @param attr The threadattr to affect
* @param guardsize The stack guard area size in bytes
* @note Thread library implementations commonly use a "guard area"
* after each thread's stack which is not readable or writable such that
* stack overflows cause a segfault; this consumes e.g. 4K of memory
* and increases memory management overhead. Setting the guard area
* size to zero hence trades off reliable behaviour on stack overflow
* for performance. */
APR_DECLARE(apr_status_t) apr_threadattr_guardsize_set(apr_threadattr_t *attr,
apr_size_t guardsize);
/**
* Create a new thread of execution
* @param new_thread The newly created thread handle.
* @param attr The threadattr to use to determine how to create the thread
* @param func The function to start the new thread in
* @param data Any data to be passed to the starting function
* @param cont The pool to use
*/
APR_DECLARE(apr_status_t) apr_thread_create(apr_thread_t **new_thread,
apr_threadattr_t *attr,
apr_thread_start_t func,
void *data, apr_pool_t *cont);
/**
* stop the current thread
* @param thd The thread to stop
* @param retval The return value to pass back to any thread that cares
*/
APR_DECLARE(apr_status_t) apr_thread_exit(apr_thread_t *thd,
apr_status_t retval);
/**
* block until the desired thread stops executing.
* @param retval The return value from the dead thread.
* @param thd The thread to join
*/
APR_DECLARE(apr_status_t) apr_thread_join(apr_status_t *retval,
apr_thread_t *thd);
/**
* force the current thread to yield the processor
*/
APR_DECLARE(void) apr_thread_yield(void);
/**
* Initialize the control variable for apr_thread_once. If this isn't
* called, apr_initialize won't work.
* @param control The control variable to initialize
* @param p The pool to allocate data from.
*/
APR_DECLARE(apr_status_t) apr_thread_once_init(apr_thread_once_t **control,
apr_pool_t *p);
/**
* Run the specified function one time, regardless of how many threads
* call it.
* @param control The control variable. The same variable should
* be passed in each time the function is tried to be
* called. This is how the underlying functions determine
* if the function has ever been called before.
* @param func The function to call.
*/
APR_DECLARE(apr_status_t) apr_thread_once(apr_thread_once_t *control,
void (*func)(void));
/**
* detach a thread
* @param thd The thread to detach
*/
APR_DECLARE(apr_status_t) apr_thread_detach(apr_thread_t *thd);
/**
* Return user data associated with the current thread.
* @param data The user data associated with the thread.
* @param key The key to associate with the data
* @param thread The currently open thread.
*/
APR_DECLARE(apr_status_t) apr_thread_data_get(void **data, const char *key,
apr_thread_t *thread);
/**
* Set user data associated with the current thread.
* @param data The user data to associate with the thread.
* @param key The key to use for associating the data with the thread
* @param cleanup The cleanup routine to use when the thread is destroyed.
* @param thread The currently open thread.
*/
APR_DECLARE(apr_status_t) apr_thread_data_set(void *data, const char *key,
apr_status_t (*cleanup) (void *),
apr_thread_t *thread);
/**
* Create and initialize a new thread private address space
* @param key The thread private handle.
* @param dest The destructor to use when freeing the private memory.
* @param cont The pool to use
*/
APR_DECLARE(apr_status_t) apr_threadkey_private_create(apr_threadkey_t **key,
void (*dest)(void *),
apr_pool_t *cont);
/**
* Get a pointer to the thread private memory
* @param new_mem The data stored in private memory
* @param key The handle for the desired thread private memory
*/
APR_DECLARE(apr_status_t) apr_threadkey_private_get(void **new_mem,
apr_threadkey_t *key);
/**
* Set the data to be stored in thread private memory
* @param priv The data to be stored in private memory
* @param key The handle for the desired thread private memory
*/
APR_DECLARE(apr_status_t) apr_threadkey_private_set(void *priv,
apr_threadkey_t *key);
/**
* Free the thread private memory
* @param key The handle for the desired thread private memory
*/
APR_DECLARE(apr_status_t) apr_threadkey_private_delete(apr_threadkey_t *key);
/**
* Return the pool associated with the current threadkey.
* @param data The user data associated with the threadkey.
* @param key The key associated with the data
* @param threadkey The currently open threadkey.
*/
APR_DECLARE(apr_status_t) apr_threadkey_data_get(void **data, const char *key,
apr_threadkey_t *threadkey);
/**
* Return the pool associated with the current threadkey.
* @param data The data to set.
* @param key The key to associate with the data.
* @param cleanup The cleanup routine to use when the file is destroyed.
* @param threadkey The currently open threadkey.
*/
APR_DECLARE(apr_status_t) apr_threadkey_data_set(void *data, const char *key,
apr_status_t (*cleanup) (void *),
apr_threadkey_t *threadkey);
#endif
/**
* Create and initialize a new procattr variable
* @param new_attr The newly created procattr.
* @param cont The pool to use
*/
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?
* @note If APR_NO_PIPE, there will be no special channel, the child
* inherits the parent's corresponding stdio stream. If APR_NO_FILE is
* specified, that corresponding stream is closed in the child (and will
* be INVALID_HANDLE_VALUE when inspected on Win32). This can have ugly
* side effects, as the next file opened in the child on Unix will fall
* into the stdio stream fd slot!
*/
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.
* @remark 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.
* @bug Note that calling this function with two NULL files on some platforms
* creates an APR_FULL_BLOCK pipe, but this behavior is neither portable nor
* is it supported. @see apr_procattr_io_set instead for simple pipes.
*/
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.
* @remark 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.
* @bug Note that calling this function with two NULL files on some platforms
* creates an APR_FULL_BLOCK pipe, but this behavior is neither portable nor
* is it supported. @see apr_procattr_io_set instead for simple pipes.
*/
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.
* @remark 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.
* @bug Note that calling this function with two NULL files on some platforms
* creates an APR_FULL_BLOCK pipe, but this behavior is neither portable nor
* is it supported. @see apr_procattr_io_set instead for simple pipes.
*/
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.
*/
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 -- Anything that the shell can handle
* APR_PROGRAM -- Executable program (default)
* APR_PROGRAM_ENV -- Executable program, copy environment
* APR_PROGRAM_PATH -- Executable program on PATH, copy env
* </PRE>
*/
APR_DECLARE(apr_status_t) apr_procattr_cmdtype_set(apr_procattr_t *attr,
apr_cmdtype_e cmd);
/**
* Determine if the child should start in detached state.
* @param attr The procattr we care about.
* @param detach Should the child start in detached state? Default is no.
*/
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
* APR_LIMIT_NOFILE
* </PRE>
* @param limit Value to set the limit to.
*/
APR_DECLARE(apr_status_t) apr_procattr_limit_set(apr_procattr_t *attr,
apr_int32_t what,
struct rlimit *limit);
#endif
/**
* Specify an error function to be called in the child process if APR
* encounters an error in the child prior to running the specified program.
* @param attr The procattr describing the child process to be created.
* @param errfn The function to call in the child process.
* @remark At the present time, it will only be called from apr_proc_create()
* on platforms where fork() is used. It will never be called on other
* platforms, on those platforms apr_proc_create() will return the error
* in the parent process rather than invoke the callback in the now-forked
* child process.
*/
APR_DECLARE(apr_status_t) apr_procattr_child_errfn_set(apr_procattr_t *attr,
apr_child_errfn_t *errfn);
/**
* Specify that apr_proc_create() should do whatever it can to report
* failures to the caller of apr_proc_create(), rather than find out in
* the child.
* @param attr The procattr describing the child process to be created.
* @param chk Flag to indicate whether or not extra work should be done
* to try to report failures to the caller.
* @remark This flag only affects apr_proc_create() on platforms where
* fork() is used. This leads to extra overhead in the calling
* process, but that may help the application handle such
* errors more gracefully.
*/
APR_DECLARE(apr_status_t) apr_procattr_error_check_set(apr_procattr_t *attr,
apr_int32_t chk);
/**
* Determine if the child should start in its own address space or using the
* current one from its parent
* @param attr The procattr we care about.
* @param addrspace Should the child start in its own address space? Default
* is no on NetWare and yes on other platforms.
*/
APR_DECLARE(apr_status_t) apr_procattr_addrspace_set(apr_procattr_t *attr,
apr_int32_t addrspace);
/**
* Set the username used for running process
* @param attr The procattr we care about.
* @param username The username used
* @param password User password if needed. Password is needed on WIN32
* or any other platform having
* APR_PROCATTR_USER_SET_REQUIRES_PASSWORD set.
*/
APR_DECLARE(apr_status_t) apr_procattr_user_set(apr_procattr_t *attr,
const char *username,
const char *password);
/**
* Set the group used for running process
* @param attr The procattr we care about.
* @param groupname The group name used
*/
APR_DECLARE(apr_status_t) apr_procattr_group_set(apr_procattr_t *attr,
const char *groupname);
#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.
* @remark returns APR_INCHILD for the child, and APR_INPARENT for the parent
* or an error.
*/
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 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. This argument
* is ignored for APR_PROGRAM_ENV, APR_PROGRAM_PATH, and
* APR_SHELLCMD_ENV types of commands.
* @param attr the procattr we should use to determine how to create the new
* process
* @param pool The pool to use.
* @note This function returns without waiting for the new process to terminate;
* use apr_proc_wait for that.
*/
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 *pool);
/**
* Wait for a child process to die
* @param proc The process handle that corresponds to the desired child process
* @param exitcode The returned exit status of the child, if a child process
* dies, or the signal that caused the child to die.
* On platforms that don't support obtaining this information,
* the status parameter will be returned as APR_ENOTIMPL.
* @param exitwhy Why the child died, the bitwise or of:
* <PRE>
* APR_PROC_EXIT -- process terminated normally
* APR_PROC_SIGNAL -- process was killed by a signal
* APR_PROC_SIGNAL_CORE -- process was killed by a signal, and
* generated a core dump.
* </PRE>
* @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>
* @remark The child's 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,
int *exitcode, apr_exit_why_e *exitwhy,
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 exitcode The returned exit status of the child, if a child process
* dies, or the signal that caused the child to die.
* On platforms that don't support obtaining this information,
* the status parameter will be returned as APR_ENOTIMPL.
* @param exitwhy Why the child died, the bitwise or of:
* <PRE>
* APR_PROC_EXIT -- process terminated normally
* APR_PROC_SIGNAL -- process was killed by a signal
* APR_PROC_SIGNAL_CORE -- process was killed by a signal, and
* generated a core dump.
* </PRE>
* @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.
* @bug Passing proc as a *proc rather than **proc was an odd choice
* for some platforms... this should be revisited in 1.0
*/
APR_DECLARE(apr_status_t) apr_proc_wait_all_procs(apr_proc_t *proc,
int *exitcode,
apr_exit_why_e *exitwhy,
apr_wait_how_e waithow,
apr_pool_t *p);
#define APR_PROC_DETACH_FOREGROUND 0 /**< Do not detach */
#define APR_PROC_DETACH_DAEMONIZE 1 /**< Detach */
/**
* Detach the process from the controlling terminal.
* @param daemonize set to non-zero if the process should daemonize
* and become a background process, else it will
* stay in the foreground.
*/
APR_DECLARE(apr_status_t) apr_proc_detach(int daemonize);
/**
* Register an other_child -- a child associated to its registered
* maintence callback. This callback is invoked when the process
* dies, is disconnected or disappears.
* @param proc The child process to register.
* @param maintenance maintenance is a function that is invoked with a
* reason and the data pointer passed here.
* @param data Opaque context data passed 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.
* @bug write_fd duplicates the proc->out stream, it's really redundant
* and should be replaced in the APR 1.0 API with a bitflag of which
* proc->in/out/err handles should be health checked.
* @bug no platform currently tests the pipes health.
*/
APR_DECLARE(void) apr_proc_other_child_register(apr_proc_t *proc,
void (*maintenance) (int reason,
void *,
int status),
void *data, apr_file_t *write_fd,
apr_pool_t *p);
/**
* Stop watching the specified other child.
* @param data The data to pass to the maintenance function. This is
* used to find the process to unregister.
* @warning 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);
/**
* Notify the maintenance callback of a registered other child process
* that application has detected an event, such as death.
* @param proc The process to check
* @param reason The reason code to pass to the maintenance function
* @param status The status to pass to the maintenance function
* @remark An example of code using this behavior;
* <pre>
* rv = apr_proc_wait_all_procs(&proc, &exitcode, &status, APR_WAIT, p);
* if (APR_STATUS_IS_CHILD_DONE(rv)) {
* \#if APR_HAS_OTHER_CHILD
* if (apr_proc_other_child_alert(&proc, APR_OC_REASON_DEATH, status)
* == APR_SUCCESS) {
* ; (already handled)
* }
* else
* \#endif
* [... handling non-otherchild processes death ...]
* </pre>
*/
APR_DECLARE(apr_status_t) apr_proc_other_child_alert(apr_proc_t *proc,
int reason,
int status);
/**
* Test one specific other child processes and invoke the maintenance callback
* with the appropriate reason code, if still running, or the appropriate reason
* code if the process is no longer healthy.
* @param ocr The registered other child
* @param reason The reason code (e.g. APR_OC_REASON_RESTART) if still running
*/
APR_DECLARE(void) apr_proc_other_child_refresh(apr_other_child_rec_t *ocr,
int reason);
/**
* Test all registered other child processes and invoke the maintenance callback
* with the appropriate reason code, if still running, or the appropriate reason
* code if the process is no longer healthy.
* @param reason The reason code (e.g. APR_OC_REASON_RESTART) to running processes
*/
APR_DECLARE(void) apr_proc_other_child_refresh_all(int reason);
/**
* Terminate a process.
* @param proc The process to terminate.
* @param sig How to kill the process.
*/
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 proc The process to register
* @param how How to kill the process, one of:
* <PRE>
* APR_KILL_NEVER -- process is never sent any signals
* APR_KILL_ALWAYS -- process is sent SIGKILL on apr_pool_t cleanup
* APR_KILL_AFTER_TIMEOUT -- SIGTERM, wait 3 seconds, SIGKILL
* APR_JUST_WAIT -- wait forever for the process to complete
* APR_KILL_ONLY_ONCE -- send SIGTERM and then wait
* </PRE>
*/
APR_DECLARE(void) apr_pool_note_subprocess(apr_pool_t *a, apr_proc_t *proc,
apr_kill_conditions_e how);
#if APR_HAS_THREADS
#if (APR_HAVE_SIGWAIT || APR_HAVE_SIGSUSPEND) && !defined(OS2)
/**
* Setup the process for a single thread to be used for all signal handling.
* @warning This must be called before any threads are created
*/
APR_DECLARE(apr_status_t) apr_setup_signal_thread(void);
/**
* Make the current thread listen for signals. This 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 signal_handler The function to call when a signal is received
* apr_status_t apr_signal_thread((int)(*signal_handler)(int signum))
*/
APR_DECLARE(apr_status_t) apr_signal_thread(int(*signal_handler)(int signum));
#endif /* (APR_HAVE_SIGWAIT || APR_HAVE_SIGSUSPEND) && !defined(OS2) */
/**
* Get the child-pool used by the thread from the thread info.
* @return apr_pool_t the pool
*/
APR_POOL_DECLARE_ACCESSOR(thread);
#endif /* APR_HAS_THREADS */
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* ! APR_THREAD_PROC_H */