/* 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
* 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
*
*/
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:
*
* APR_LIMIT_CPU
* APR_LIMIT_MEM
* APR_LIMIT_NPROC
* APR_LIMIT_NOFILE
*
* @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:
*
* 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.
*
* @param waithow How should we wait. One of:
*
* APR_WAIT -- block until the child process dies.
* APR_NOWAIT -- return immediately regardless of if the
* child is dead or not.
*
* @remark The childs status is in the return code to this process. It is one of:
*
* APR_CHILD_DONE -- child is no longer running.
* APR_CHILD_NOTDONE -- child is still running.
*
*/
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:
*
* 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.
*
* @param waithow How should we wait. One of:
*
* APR_WAIT -- block until the child process dies.
* APR_NOWAIT -- return immediately regardless of if the
* child is dead or not.
*
* @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;
*
* 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 ...]
*
*/
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:
*
* 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
*
*/
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 */