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diff --git a/include/apr_thread_proc.h b/include/apr_thread_proc.h new file mode 100644 index 0000000..ea3c43f --- /dev/null +++ b/include/apr_thread_proc.h @@ -0,0 +1,846 @@ +/* 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" +#include "apr_perms_set.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); + + +/** + * Register permission set function + * @param attr The procattr we care about. + * @param perms_set_fn Permission set callback + * @param data Data to pass to permission callback function + * @param perms Permissions to set + */ +APR_DECLARE(apr_status_t) apr_procattr_perms_set_register(apr_procattr_t *attr, + apr_perms_setfn_t *perms_set_fn, + void *data, + apr_fileperms_t perms); + +#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)) + * @note Synchronous signals like SIGABRT/SIGSEGV/SIGBUS/... are ignored by + * apr_signal_thread() and thus can't be waited by this function (they remain + * handled by the operating system or its native signals interface). + * @remark In APR version 1.6 and ealier, SIGUSR2 was part of these ignored + * signals and thus was never passed in to the signal_handler. From APR 1.7 + * this is no more the case so SIGUSR2 can be handled in signal_handler and + * acted upon like the other asynchronous signals. + */ +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 */ + |