X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Futil%2Fscheduler.c;h=48a3f04ce3cd895053299df11b5fc8151e0d10ef;hb=8fa757a9418eed2685595227c86c3c34c389adcf;hp=6231a198753efe280b689c330c6e91797a0d15f3;hpb=9cefd9c5522797b132749ca7d99a930007d28347;p=oweals%2Fgnunet.git diff --git a/src/util/scheduler.c b/src/util/scheduler.c index 6231a1987..48a3f04ce 100644 --- a/src/util/scheduler.c +++ b/src/util/scheduler.c @@ -1,39 +1,38 @@ /* This file is part of GNUnet - (C) 2009, 2011 Christian Grothoff (and other contributing authors) + Copyright (C) 2009-2017 GNUnet e.V. - GNUnet is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published - by the Free Software Foundation; either version 2, or (at your - option) any later version. + GNUnet is free software: you can redistribute it and/or modify it + under the terms of the GNU Affero General Public License as published + by the Free Software Foundation, either version 3 of the License, + or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - General Public License for more details. + Affero General Public License for more details. - You should have received a copy of the GNU General Public License - along with GNUnet; see the file COPYING. If not, write to the - Free Software Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. - */ + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . + SPDX-License-Identifier: AGPL3.0-or-later + */ /** * @file util/scheduler.c * @brief schedule computations using continuation passing style * @author Christian Grothoff */ #include "platform.h" -#include "gnunet_common.h" -#include "gnunet_os_lib.h" -#include "gnunet_scheduler_lib.h" -#include "gnunet_signal_lib.h" -#include "gnunet_time_lib.h" +#include "gnunet_util_lib.h" #include "disk.h" +// DEBUG +#include -#define LOG(kind,...) GNUNET_log_from (kind, "util-scheduler", __VA_ARGS__) +#define LOG(kind, ...) GNUNET_log_from (kind, "util-scheduler", __VA_ARGS__) -#define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util-scheduler", syscall) +#define LOG_STRERROR(kind, syscall) GNUNET_log_from_strerror (kind, \ + "util-scheduler", \ + syscall) #if HAVE_EXECINFO_H @@ -75,48 +74,112 @@ /** - * Linked list of pending tasks. + * Argument to be passed from the driver to + * #GNUNET_SCHEDULER_do_work(). Contains the + * scheduler's internal state. + */ +struct GNUNET_SCHEDULER_Handle +{ + /** + * Passed here to avoid constantly allocating/deallocating + * this element, but generally we want to get rid of this. + * @deprecated + */ + struct GNUNET_NETWORK_FDSet *rs; + + /** + * Passed here to avoid constantly allocating/deallocating + * this element, but generally we want to get rid of this. + * @deprecated + */ + struct GNUNET_NETWORK_FDSet *ws; + + /** + * context of the SIGINT handler + */ + struct GNUNET_SIGNAL_Context *shc_int; + + /** + * context of the SIGTERM handler + */ + struct GNUNET_SIGNAL_Context *shc_term; + +#if (SIGTERM != GNUNET_TERM_SIG) + /** + * context of the TERM_SIG handler + */ + struct GNUNET_SIGNAL_Context *shc_gterm; +#endif + + /** + * context of the SIGQUIT handler + */ + struct GNUNET_SIGNAL_Context *shc_quit; + + /** + * context of the SIGHUP handler + */ + struct GNUNET_SIGNAL_Context *shc_hup; + + /** + * context of hte SIGPIPE handler + */ + struct GNUNET_SIGNAL_Context *shc_pipe; +}; + + +/** + * Entry in list of pending tasks. */ -struct Task +struct GNUNET_SCHEDULER_Task { /** * This is a linked list. */ - struct Task *next; + struct GNUNET_SCHEDULER_Task *next; + + /** + * This is a linked list. + */ + struct GNUNET_SCHEDULER_Task *prev; /** * Function to run when ready. */ - GNUNET_SCHEDULER_Task callback; + GNUNET_SCHEDULER_TaskCallback callback; /** - * Closure for the callback. + * Closure for the @e callback. */ void *callback_cls; /** - * Set of file descriptors this task is waiting - * for for reading. Once ready, this is updated - * to reflect the set of file descriptors ready - * for operation. + * Information about which FDs are ready for this task (and why). + */ + struct GNUNET_SCHEDULER_FdInfo *fds; + + /** + * Storage location used for @e fds if we want to avoid + * a separate malloc() call in the common case that this + * task is only about a single FD. */ - struct GNUNET_NETWORK_FDSet *read_set; + struct GNUNET_SCHEDULER_FdInfo fdx; /** - * Set of file descriptors this task is waiting for for writing. - * Once ready, this is updated to reflect the set of file - * descriptors ready for operation. + * Size of the @e fds array. */ - struct GNUNET_NETWORK_FDSet *write_set; + unsigned int fds_len; /** - * Unique task identifier. + * Do we own the network and file handles referenced by the FdInfo + * structs in the fds array. This will only be GNUNET_YES if the + * task was created by the #GNUNET_SCHEDULER_add_select function. */ - GNUNET_SCHEDULER_TaskIdentifier id; + int own_handles; /** * Absolute timeout value for the task, or - * GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout". + * #GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout". */ struct GNUNET_TIME_Absolute timeout; @@ -155,6 +218,16 @@ struct Task */ int lifeness; + /** + * Is this task run on shutdown? + */ + int on_shutdown; + + /** + * Is this task in the ready list? + */ + int in_ready_list; + #if EXECINFO /** * Array of strings which make up a backtrace from the point when this @@ -168,14 +241,103 @@ struct Task int num_backtrace_strings; #endif + /** + * Asynchronous scope of the task that scheduled this scope, + */ + struct GNUNET_AsyncScopeSave scope; +}; + + +/** + * A struct representing an event the select driver is waiting for + */ +struct Scheduled +{ + struct Scheduled *prev; + + struct Scheduled *next; + + /** + * the task, the event is related to + */ + struct GNUNET_SCHEDULER_Task *task; + + /** + * information about the network socket / file descriptor where + * the event is expected to occur + */ + struct GNUNET_SCHEDULER_FdInfo *fdi; + + /** + * the event types (multiple event types can be ORed) the select + * driver is expected to wait for + */ + enum GNUNET_SCHEDULER_EventType et; +}; + + +/** + * Driver context used by GNUNET_SCHEDULER_run + */ +struct DriverContext +{ + /** + * the head of a DLL containing information about the events the + * select driver is waiting for + */ + struct Scheduled *scheduled_head; + + /** + * the tail of a DLL containing information about the events the + * select driver is waiting for + */ + struct Scheduled *scheduled_tail; + /** + * the time when the select driver will wake up again (after + * calling select) + */ + struct GNUNET_TIME_Absolute timeout; }; /** - * List of tasks waiting for an event. + * The driver used for the event loop. Will be handed over to + * the scheduler in #GNUNET_SCHEDULER_do_work(), persisted + * there in this variable for later use in functions like + * #GNUNET_SCHEDULER_add_select(), #add_without_sets() and + * #GNUNET_SCHEDULER_cancel(). + */ +static const struct GNUNET_SCHEDULER_Driver *scheduler_driver; + +/** + * Head of list of tasks waiting for an event. + */ +static struct GNUNET_SCHEDULER_Task *pending_head; + +/** + * Tail of list of tasks waiting for an event. + */ +static struct GNUNET_SCHEDULER_Task *pending_tail; + +/** + * Head of list of tasks waiting for shutdown. + */ +static struct GNUNET_SCHEDULER_Task *shutdown_head; + +/** + * Tail of list of tasks waiting for shutdown. + */ +static struct GNUNET_SCHEDULER_Task *shutdown_tail; + +/** + * List of tasks waiting ONLY for a timeout event. + * Sorted by timeout (earliest first). Used so that + * we do not traverse the list of these tasks when + * building select sets (we just look at the head + * to determine the respective timeout ONCE). */ -static struct Task *pending; +static struct GNUNET_SCHEDULER_Task *pending_timeout_head; /** * List of tasks waiting ONLY for a timeout event. @@ -184,41 +346,48 @@ static struct Task *pending; * building select sets (we just look at the head * to determine the respective timeout ONCE). */ -static struct Task *pending_timeout; +static struct GNUNET_SCHEDULER_Task *pending_timeout_tail; /** * Last inserted task waiting ONLY for a timeout event. * Used to (heuristically) speed up insertion. */ -static struct Task *pending_timeout_last; +static struct GNUNET_SCHEDULER_Task *pending_timeout_last; /** * ID of the task that is running right now. */ -static struct Task *active_task; +static struct GNUNET_SCHEDULER_Task *active_task; /** - * List of tasks ready to run right now, - * grouped by importance. + * Head of list of tasks ready to run right now, grouped by importance. */ -static struct Task *ready[GNUNET_SCHEDULER_PRIORITY_COUNT]; +static struct +GNUNET_SCHEDULER_Task *ready_head[GNUNET_SCHEDULER_PRIORITY_COUNT]; /** - * Identity of the last task queued. Incremented for each task to - * generate a unique task ID (it is virtually impossible to start - * more than 2^64 tasks during the lifetime of a process). + * Tail of list of tasks ready to run right now, grouped by importance. */ -static GNUNET_SCHEDULER_TaskIdentifier last_id; +static struct +GNUNET_SCHEDULER_Task *ready_tail[GNUNET_SCHEDULER_PRIORITY_COUNT]; /** - * Number of tasks on the ready list. + * Task for installing parent control handlers (it might happen that the + * scheduler is shutdown before this task is executed, so + * GNUNET_SCHEDULER_shutdown must cancel it in that case) */ -static unsigned int ready_count; +static struct GNUNET_SCHEDULER_Task *install_parent_control_task; + +/** + * Task for reading from a pipe that signal handlers will use to initiate + * shutdown + */ +static struct GNUNET_SCHEDULER_Task *shutdown_pipe_task; /** - * How many tasks have we run so far? + * Number of tasks on the ready list. */ -static unsigned long long tasks_run; +static unsigned int ready_count; /** * Priority of the task running right now. Only @@ -239,20 +408,26 @@ static int current_lifeness; /** * Function to use as a select() in the scheduler. - * If NULL, we use GNUNET_NETWORK_socket_select (). + * If NULL, we use GNUNET_NETWORK_socket_select(). */ static GNUNET_SCHEDULER_select scheduler_select; /** - * Closure for 'scheduler_select'. + * Task context of the current task. + */ +static struct GNUNET_SCHEDULER_TaskContext tc; + +/** + * Closure for #scheduler_select. */ static void *scheduler_select_cls; + /** * Sets the select function to use in the scheduler (scheduler_select). * * @param new_select new select function to use - * @param new_select_cls closure for 'new_select' + * @param new_select_cls closure for @a new_select * @return previously used select function, NULL for default */ void @@ -281,115 +456,45 @@ check_priority (enum GNUNET_SCHEDULER_Priority p) /** - * Update all sets and timeout for select. - * - * @param rs read-set, set to all FDs we would like to read (updated) - * @param ws write-set, set to all FDs we would like to write (updated) - * @param timeout next timeout (updated) + * chooses the nearest timeout from all pending tasks, to be used + * to tell the driver the next wakeup time (using its set_wakeup + * callback) */ -static void -update_sets (struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws, - struct GNUNET_TIME_Relative *timeout) +struct GNUNET_TIME_Absolute +get_timeout () { - struct Task *pos; + struct GNUNET_SCHEDULER_Task *pos; struct GNUNET_TIME_Absolute now; - struct GNUNET_TIME_Relative to; + struct GNUNET_TIME_Absolute timeout; + pos = pending_timeout_head; now = GNUNET_TIME_absolute_get (); - pos = pending_timeout; - if (pos != NULL) - { - to = GNUNET_TIME_absolute_get_difference (now, pos->timeout); - if (timeout->rel_value > to.rel_value) - *timeout = to; - if (pos->reason != 0) - *timeout = GNUNET_TIME_UNIT_ZERO; - } - pos = pending; - while (pos != NULL) + timeout = GNUNET_TIME_UNIT_FOREVER_ABS; + if (NULL != pos) { - if (pos->timeout.abs_value != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value) + if (0 != pos->reason) { - to = GNUNET_TIME_absolute_get_difference (now, pos->timeout); - if (timeout->rel_value > to.rel_value) - *timeout = to; + return now; + } + else + { + timeout = pos->timeout; } - if (pos->read_fd != -1) - GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd); - if (pos->write_fd != -1) - GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd); - if (pos->read_set != NULL) - GNUNET_NETWORK_fdset_add (rs, pos->read_set); - if (pos->write_set != NULL) - GNUNET_NETWORK_fdset_add (ws, pos->write_set); - if (pos->reason != 0) - *timeout = GNUNET_TIME_UNIT_ZERO; - pos = pos->next; } -} - - -/** - * Check if the ready set overlaps with the set we want to have ready. - * If so, update the want set (set all FDs that are ready). If not, - * return GNUNET_NO. - * - * @param ready set that is ready - * @param want set that we want to be ready - * @return GNUNET_YES if there was some overlap - */ -static int -set_overlaps (const struct GNUNET_NETWORK_FDSet *ready, - struct GNUNET_NETWORK_FDSet *want) -{ - if ((NULL == want) || (NULL == ready)) - return GNUNET_NO; - if (GNUNET_NETWORK_fdset_overlap (ready, want)) + for (pos = pending_head; NULL != pos; pos = pos->next) { - /* copy all over (yes, there maybe unrelated bits, - * but this should not hurt well-written clients) */ - GNUNET_NETWORK_fdset_copy (want, ready); - return GNUNET_YES; + if (0 != pos->reason) + { + return now; + } + else if ((pos->timeout.abs_value_us != + GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us) && + (timeout.abs_value_us > pos->timeout.abs_value_us)) + { + timeout = pos->timeout; + } } - return GNUNET_NO; -} - - -/** - * Check if the given task is eligible to run now. - * Also set the reason why it is eligible. - * - * @param task task to check if it is ready - * @param now the current time - * @param rs set of FDs ready for reading - * @param ws set of FDs ready for writing - * @return GNUNET_YES if we can run it, GNUNET_NO if not. - */ -static int -is_ready (struct Task *task, struct GNUNET_TIME_Absolute now, - const struct GNUNET_NETWORK_FDSet *rs, - const struct GNUNET_NETWORK_FDSet *ws) -{ - enum GNUNET_SCHEDULER_Reason reason; - - reason = task->reason; - if (now.abs_value >= task->timeout.abs_value) - reason |= GNUNET_SCHEDULER_REASON_TIMEOUT; - if ((0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) && - (((task->read_fd != -1) && - (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (rs, task->read_fd))) || - (set_overlaps (rs, task->read_set)))) - reason |= GNUNET_SCHEDULER_REASON_READ_READY; - if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) && - (((task->write_fd != -1) && - (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (ws, task->write_fd))) - || (set_overlaps (ws, task->write_set)))) - reason |= GNUNET_SCHEDULER_REASON_WRITE_READY; - if (reason == 0) - return GNUNET_NO; /* not ready */ - reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE; - task->reason = reason; - return GNUNET_YES; + return timeout; } @@ -399,221 +504,117 @@ is_ready (struct Task *task, struct GNUNET_TIME_Absolute now, * @param task task ready for execution */ static void -queue_ready_task (struct Task *task) +queue_ready_task (struct GNUNET_SCHEDULER_Task *task) { - enum GNUNET_SCHEDULER_Priority p = task->priority; + enum GNUNET_SCHEDULER_Priority p = check_priority (task->priority); - if (0 != (task->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) - p = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN; - task->next = ready[check_priority (p)]; - ready[check_priority (p)] = task; + GNUNET_CONTAINER_DLL_insert (ready_head[p], + ready_tail[p], + task); + task->in_ready_list = GNUNET_YES; ready_count++; } /** - * Check which tasks are ready and move them - * to the respective ready queue. - * - * @param rs FDs ready for reading - * @param ws FDs ready for writing - */ -static void -check_ready (const struct GNUNET_NETWORK_FDSet *rs, - const struct GNUNET_NETWORK_FDSet *ws) -{ - struct Task *pos; - struct Task *prev; - struct Task *next; - struct GNUNET_TIME_Absolute now; - - now = GNUNET_TIME_absolute_get (); - prev = NULL; - pos = pending_timeout; - while (pos != NULL) - { - next = pos->next; - if (now.abs_value >= pos->timeout.abs_value) - pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT; - if (0 == pos->reason) - break; - pending_timeout = next; - if (pending_timeout_last == pos) - pending_timeout_last = NULL; - queue_ready_task (pos); - pos = next; - } - pos = pending; - while (pos != NULL) - { - LOG (GNUNET_ERROR_TYPE_DEBUG, - "Checking readiness of task: %llu / %p\n", - pos->id, pos->callback_cls); - next = pos->next; - if (GNUNET_YES == is_ready (pos, now, rs, ws)) - { - if (prev == NULL) - pending = next; - else - prev->next = next; - queue_ready_task (pos); - pos = next; - continue; - } - prev = pos; - pos = next; - } -} - - -/** - * Request the shutdown of a scheduler. Marks all currently - * pending tasks as ready because of shutdown. This will - * cause all tasks to run (as soon as possible, respecting - * priorities and prerequisite tasks). Note that tasks - * scheduled AFTER this call may still be delayed arbitrarily. + * Request the shutdown of a scheduler. Marks all tasks + * awaiting shutdown as ready. Note that tasks + * scheduled with #GNUNET_SCHEDULER_add_shutdown() AFTER this call + * will be delayed until the next shutdown signal. */ void GNUNET_SCHEDULER_shutdown () { - struct Task *pos; - int i; + struct GNUNET_SCHEDULER_Task *pos; - pos = pending_timeout; - while (pos != NULL) + LOG (GNUNET_ERROR_TYPE_DEBUG, + "GNUNET_SCHEDULER_shutdown\n"); + if (NULL != install_parent_control_task) { - pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN; - /* we don't move the task into the ready queue yet; check_ready - * will do that later, possibly adding additional - * readiness-factors */ - pos = pos->next; + GNUNET_SCHEDULER_cancel (install_parent_control_task); + install_parent_control_task = NULL; } - pos = pending; - while (pos != NULL) + if (NULL != shutdown_pipe_task) { - pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN; - /* we don't move the task into the ready queue yet; check_ready - * will do that later, possibly adding additional - * readiness-factors */ - pos = pos->next; + GNUNET_SCHEDULER_cancel (shutdown_pipe_task); + shutdown_pipe_task = NULL; } - for (i = 0; i < GNUNET_SCHEDULER_PRIORITY_COUNT; i++) + while (NULL != (pos = shutdown_head)) { - pos = ready[i]; - while (pos != NULL) - { - pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN; - /* we don't move the task into the ready queue yet; check_ready - * will do that later, possibly adding additional - * readiness-factors */ - pos = pos->next; - } + GNUNET_CONTAINER_DLL_remove (shutdown_head, + shutdown_tail, + pos); + pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN; + queue_ready_task (pos); } } /** - * Destroy a task (release associated resources) + * Output stack trace of task @a t. * - * @param t task to destroy + * @param t task to dump stack trace of */ static void -destroy_task (struct Task *t) +dump_backtrace (struct GNUNET_SCHEDULER_Task *t) { - if (NULL != t->read_set) - GNUNET_NETWORK_fdset_destroy (t->read_set); - if (NULL != t->write_set) - GNUNET_NETWORK_fdset_destroy (t->write_set); #if EXECINFO - GNUNET_free (t->backtrace_strings); + for (unsigned int i = 0; i < t->num_backtrace_strings; i++) + LOG (GNUNET_ERROR_TYPE_WARNING, + "Task %p trace %u: %s\n", + t, + i, + t->backtrace_strings[i]); +#else + (void) t; #endif - GNUNET_free (t); } /** - * Run at least one task in the highest-priority queue that is not - * empty. Keep running tasks until we are either no longer running - * "URGENT" tasks or until we have at least one "pending" task (which - * may become ready, hence we should select on it). Naturally, if - * there are no more ready tasks, we also return. + * Destroy a task (release associated resources) * - * @param rs FDs ready for reading - * @param ws FDs ready for writing + * @param t task to destroy */ static void -run_ready (struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws) +destroy_task (struct GNUNET_SCHEDULER_Task *t) { - enum GNUNET_SCHEDULER_Priority p; - struct Task *pos; - struct GNUNET_SCHEDULER_TaskContext tc; + unsigned int i; - max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP; - do + LOG (GNUNET_ERROR_TYPE_DEBUG, + "destroying task %p\n", + t); + + if (GNUNET_YES == t->own_handles) { - if (ready_count == 0) - return; - GNUNET_assert (ready[GNUNET_SCHEDULER_PRIORITY_KEEP] == NULL); - /* yes, p>0 is correct, 0 is "KEEP" which should - * always be an empty queue (see assertion)! */ - for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--) - { - pos = ready[p]; - if (pos != NULL) - break; - } - GNUNET_assert (pos != NULL); /* ready_count wrong? */ - ready[p] = pos->next; - ready_count--; - if (current_priority != pos->priority) - { - current_priority = pos->priority; - (void) GNUNET_OS_set_process_priority (GNUNET_OS_process_current (), - pos->priority); - } - current_lifeness = pos->lifeness; - active_task = pos; -#if PROFILE_DELAYS - if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value > - DELAY_THRESHOLD.rel_value) + for (i = 0; i != t->fds_len; ++i) { - LOG (GNUNET_ERROR_TYPE_DEBUG, - "Task %llu took %s to be scheduled\n", - (unsigned long long) pos->id, - GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time), GNUNET_YES)); + const struct GNUNET_NETWORK_Handle *fd = t->fds[i].fd; + const struct GNUNET_DISK_FileHandle *fh = t->fds[i].fh; + if (fd) + { + GNUNET_NETWORK_socket_free_memory_only_ ((struct + GNUNET_NETWORK_Handle *) fd); + } + if (fh) + { + // FIXME: on WIN32 this is not enough! A function + // GNUNET_DISK_file_free_memory_only would be nice + GNUNET_free ((void *) fh); + } } -#endif - tc.reason = pos->reason; - tc.read_ready = (pos->read_set == NULL) ? rs : pos->read_set; - if ((pos->read_fd != -1) && - (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY))) - GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd); - tc.write_ready = (pos->write_set == NULL) ? ws : pos->write_set; - if ((pos->write_fd != -1) && - (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY))) - GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd); - if (((tc.reason & GNUNET_SCHEDULER_REASON_WRITE_READY) != 0) && - (pos->write_fd != -1) && - (!GNUNET_NETWORK_fdset_test_native (ws, pos->write_fd))) - GNUNET_abort (); // added to ready in previous select loop! - LOG (GNUNET_ERROR_TYPE_DEBUG, - "Running task: %llu / %p\n", pos->id, - pos->callback_cls); - pos->callback (pos->callback_cls, &tc); + } + if (t->fds_len > 1) + { + GNUNET_array_grow (t->fds, t->fds_len, 0); + } #if EXECINFO - int i; - - for (i = 0; i < pos->num_backtrace_strings; i++) - LOG (GNUNET_ERROR_TYPE_ERROR, "Task %llu trace %d: %s\n", pos->id, i, - pos->backtrace_strings[i]); + GNUNET_free (t->backtrace_strings); #endif - active_task = NULL; - destroy_task (pos); - tasks_run++; - } - while ((pending == NULL) || (p >= max_priority_added)); + GNUNET_free (t); } + /** * Pipe used to communicate shutdown via signal. */ @@ -628,13 +629,31 @@ static pid_t my_pid; /** * Signal handler called for SIGPIPE. */ -#ifndef MINGW static void sighandler_pipe () { return; } -#endif + + +///** +// * Wait for a short time. +// * Sleeps for @a ms ms (as that should be long enough for virtually all +// * modern systems to context switch and allow another process to do +// * some 'real' work). +// * +// * @param ms how many ms to wait +// */ +// static void +// short_wait (unsigned int ms) +// { +// struct GNUNET_TIME_Relative timeout; +// +// timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, ms); +// (void) GNUNET_NETWORK_socket_select (NULL, NULL, NULL, timeout); +// } + + /** * Signal handler called for signals that should cause us to shutdown. */ @@ -645,192 +664,90 @@ sighandler_shutdown () int old_errno = errno; /* backup errno */ if (getpid () != my_pid) - exit (1); /* we have fork'ed since the signal handler was created, - * ignore the signal, see https://gnunet.org/vfork discussion */ + _exit (1); /* we have fork'ed since the signal handler was created, + * ignore the signal, see https://gnunet.org/vfork discussion */ GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle - (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE), - &c, sizeof (c)); + (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE), + &c, sizeof(c)); errno = old_errno; } -/** - * Check if the system is still life. Trigger shutdown if we - * have tasks, but none of them give us lifeness. - * - * @return GNUNET_OK to continue the main loop, - * GNUNET_NO to exit - */ -static int -check_lifeness () +static void +shutdown_if_no_lifeness () { - struct Task *t; + struct GNUNET_SCHEDULER_Task *t; if (ready_count > 0) - return GNUNET_OK; - for (t = pending; NULL != t; t = t->next) - if (t->lifeness == GNUNET_YES) - return GNUNET_OK; - for (t = pending_timeout; NULL != t; t = t->next) - if (t->lifeness == GNUNET_YES) - return GNUNET_OK; - if ((NULL != pending) || (NULL != pending_timeout)) - { - GNUNET_SCHEDULER_shutdown (); - return GNUNET_OK; - } - return GNUNET_NO; + return; + for (t = pending_head; NULL != t; t = t->next) + if (GNUNET_YES == t->lifeness) + return; + for (t = shutdown_head; NULL != t; t = t->next) + if (GNUNET_YES == t->lifeness) + return; + for (t = pending_timeout_head; NULL != t; t = t->next) + if (GNUNET_YES == t->lifeness) + return; + /* No lifeness! */ + GNUNET_SCHEDULER_shutdown (); } +static int +select_loop (struct GNUNET_SCHEDULER_Handle *sh, + struct DriverContext *context); + + /** * Initialize and run scheduler. This function will return when all * tasks have completed. On systems with signals, receiving a SIGTERM - * (and other similar signals) will cause "GNUNET_SCHEDULER_shutdown" + * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown() * to be run after the active task is complete. As a result, SIGTERM * causes all active tasks to be scheduled with reason - * "GNUNET_SCHEDULER_REASON_SHUTDOWN". (However, tasks added + * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added * afterwards will execute normally!). Note that any particular signal * will only shut down one scheduler; applications should always only * create a single scheduler. * * @param task task to run immediately - * @param task_cls closure of task + * @param task_cls closure of @a task */ void -GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls) +GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { - struct GNUNET_NETWORK_FDSet *rs; - struct GNUNET_NETWORK_FDSet *ws; - struct GNUNET_TIME_Relative timeout; - int ret; - struct GNUNET_SIGNAL_Context *shc_int; - struct GNUNET_SIGNAL_Context *shc_term; - -#ifndef MINGW - struct GNUNET_SIGNAL_Context *shc_quit; - struct GNUNET_SIGNAL_Context *shc_hup; - struct GNUNET_SIGNAL_Context *shc_pipe; -#endif - unsigned long long last_tr; - unsigned int busy_wait_warning; - const struct GNUNET_DISK_FileHandle *pr; - char c; - - GNUNET_assert (active_task == NULL); - rs = GNUNET_NETWORK_fdset_create (); - ws = GNUNET_NETWORK_fdset_create (); - GNUNET_assert (shutdown_pipe_handle == NULL); - shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO, GNUNET_NO, GNUNET_NO); - GNUNET_assert (shutdown_pipe_handle != NULL); - pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle, - GNUNET_DISK_PIPE_END_READ); - GNUNET_assert (pr != NULL); - my_pid = getpid (); - shc_int = GNUNET_SIGNAL_handler_install (SIGINT, &sighandler_shutdown); - shc_term = GNUNET_SIGNAL_handler_install (SIGTERM, &sighandler_shutdown); -#ifndef MINGW - shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE, &sighandler_pipe); - shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT, &sighandler_shutdown); - shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP, &sighandler_shutdown); -#endif - current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT; - current_lifeness = GNUNET_YES; - GNUNET_SCHEDULER_add_continuation (task, task_cls, - GNUNET_SCHEDULER_REASON_STARTUP); - active_task = (void *) (long) -1; /* force passing of sanity check */ - GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO, - &GNUNET_OS_install_parent_control_handler, - NULL); - active_task = NULL; - last_tr = 0; - busy_wait_warning = 0; - while (GNUNET_OK == check_lifeness ()) - { - GNUNET_NETWORK_fdset_zero (rs); - GNUNET_NETWORK_fdset_zero (ws); - timeout = GNUNET_TIME_UNIT_FOREVER_REL; - update_sets (rs, ws, &timeout); - GNUNET_NETWORK_fdset_handle_set (rs, pr); - if (ready_count > 0) - { - /* no blocking, more work already ready! */ - timeout = GNUNET_TIME_UNIT_ZERO; - } - if (NULL == scheduler_select) - ret = GNUNET_NETWORK_socket_select (rs, ws, NULL, timeout); - else - ret = scheduler_select (scheduler_select_cls, rs, ws, NULL, timeout); - if (ret == GNUNET_SYSERR) - { - if (errno == EINTR) - continue; - - LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "select"); -#ifndef MINGW -#if USE_LSOF - char lsof[512]; - - snprintf (lsof, sizeof (lsof), "lsof -p %d", getpid ()); - (void) close (1); - (void) dup2 (2, 1); - if (0 != system (lsof)) - LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING, "system"); -#endif -#endif - GNUNET_abort (); - break; - } - if ((ret == 0) && (timeout.rel_value == 0) && (busy_wait_warning > 16)) - { - LOG (GNUNET_ERROR_TYPE_WARNING, _("Looks like we're busy waiting...\n")); - sleep (1); /* mitigate */ - } - check_ready (rs, ws); - run_ready (rs, ws); - if (GNUNET_NETWORK_fdset_handle_isset (rs, pr)) - { - /* consume the signal */ - GNUNET_DISK_file_read (pr, &c, sizeof (c)); - /* mark all active tasks as ready due to shutdown */ - GNUNET_SCHEDULER_shutdown (); - } - if (last_tr == tasks_run) - { - busy_wait_warning++; - } - else - { - last_tr = tasks_run; - busy_wait_warning = 0; - } - } - GNUNET_SIGNAL_handler_uninstall (shc_int); - GNUNET_SIGNAL_handler_uninstall (shc_term); -#ifndef MINGW - GNUNET_SIGNAL_handler_uninstall (shc_pipe); - GNUNET_SIGNAL_handler_uninstall (shc_quit); - GNUNET_SIGNAL_handler_uninstall (shc_hup); -#endif - GNUNET_DISK_pipe_close (shutdown_pipe_handle); - shutdown_pipe_handle = NULL; - GNUNET_NETWORK_fdset_destroy (rs); - GNUNET_NETWORK_fdset_destroy (ws); -} + struct GNUNET_SCHEDULER_Handle *sh; + struct GNUNET_SCHEDULER_Driver *driver; + struct DriverContext context = { .scheduled_head = NULL, + .scheduled_tail = NULL, + .timeout = GNUNET_TIME_absolute_get () }; + + driver = GNUNET_SCHEDULER_driver_select (); + driver->cls = &context; + sh = GNUNET_SCHEDULER_driver_init (driver); + GNUNET_SCHEDULER_add_with_reason_and_priority (task, + task_cls, + GNUNET_SCHEDULER_REASON_STARTUP, + GNUNET_SCHEDULER_PRIORITY_DEFAULT); + select_loop (sh, + &context); + GNUNET_SCHEDULER_driver_done (sh); + GNUNET_free (driver); +} /** - * Obtain the reason code for why the current task was - * started. Will return the same value as - * the GNUNET_SCHEDULER_TaskContext's reason field. + * Obtain the task context, giving the reason why the current task was + * started. * - * @return reason(s) why the current task is run + * @return current tasks' scheduler context */ -enum GNUNET_SCHEDULER_Reason -GNUNET_SCHEDULER_get_reason () +const struct GNUNET_SCHEDULER_TaskContext * +GNUNET_SCHEDULER_get_task_context () { - GNUNET_assert (active_task != NULL); - return active_task->reason; + GNUNET_assert (NULL != active_task); + return &tc; } @@ -846,290 +763,478 @@ GNUNET_SCHEDULER_get_reason () unsigned int GNUNET_SCHEDULER_get_load (enum GNUNET_SCHEDULER_Priority p) { - struct Task *pos; + struct GNUNET_SCHEDULER_Task *pos; unsigned int ret; - GNUNET_assert (active_task != NULL); + GNUNET_assert (NULL != active_task); if (p == GNUNET_SCHEDULER_PRIORITY_COUNT) return ready_count; if (p == GNUNET_SCHEDULER_PRIORITY_KEEP) p = current_priority; ret = 0; - pos = ready[check_priority (p)]; - while (pos != NULL) - { - pos = pos->next; + for (pos = ready_head[check_priority (p)]; NULL != pos; pos = pos->next) ret++; - } return ret; } +void +init_fd_info (struct GNUNET_SCHEDULER_Task *t, + const struct GNUNET_NETWORK_Handle *const *read_nh, + unsigned int read_nh_len, + const struct GNUNET_NETWORK_Handle *const *write_nh, + unsigned int write_nh_len, + const struct GNUNET_DISK_FileHandle *const *read_fh, + unsigned int read_fh_len, + const struct GNUNET_DISK_FileHandle *const *write_fh, + unsigned int write_fh_len) +{ + // FIXME: if we have exactly two network handles / exactly two file handles + // and they are equal, we can make one FdInfo with both + // GNUNET_SCHEDULER_ET_IN and GNUNET_SCHEDULER_ET_OUT set. + struct GNUNET_SCHEDULER_FdInfo *fdi; + + t->fds_len = read_nh_len + write_nh_len + read_fh_len + write_fh_len; + if (1 == t->fds_len) + { + fdi = &t->fdx; + t->fds = fdi; + if (1 == read_nh_len) + { + GNUNET_assert (NULL != read_nh); + GNUNET_assert (NULL != *read_nh); + fdi->fd = *read_nh; + fdi->et = GNUNET_SCHEDULER_ET_IN; + fdi->sock = GNUNET_NETWORK_get_fd (*read_nh); + t->read_fd = fdi->sock; + t->write_fd = -1; + } + else if (1 == write_nh_len) + { + GNUNET_assert (NULL != write_nh); + GNUNET_assert (NULL != *write_nh); + fdi->fd = *write_nh; + fdi->et = GNUNET_SCHEDULER_ET_OUT; + fdi->sock = GNUNET_NETWORK_get_fd (*write_nh); + t->read_fd = -1; + t->write_fd = fdi->sock; + } + else if (1 == read_fh_len) + { + GNUNET_assert (NULL != read_fh); + GNUNET_assert (NULL != *read_fh); + fdi->fh = *read_fh; + fdi->et = GNUNET_SCHEDULER_ET_IN; + fdi->sock = (*read_fh)->fd; // FIXME: does not work under WIN32 + t->read_fd = fdi->sock; + t->write_fd = -1; + } + else + { + GNUNET_assert (NULL != write_fh); + GNUNET_assert (NULL != *write_fh); + fdi->fh = *write_fh; + fdi->et = GNUNET_SCHEDULER_ET_OUT; + fdi->sock = (*write_fh)->fd; // FIXME: does not work under WIN32 + t->read_fd = -1; + t->write_fd = fdi->sock; + } + } + else + { + fdi = GNUNET_new_array (t->fds_len, struct GNUNET_SCHEDULER_FdInfo); + t->fds = fdi; + t->read_fd = -1; + t->write_fd = -1; + unsigned int i; + for (i = 0; i != read_nh_len; ++i) + { + fdi->fd = read_nh[i]; + GNUNET_assert (NULL != fdi->fd); + fdi->et = GNUNET_SCHEDULER_ET_IN; + fdi->sock = GNUNET_NETWORK_get_fd (read_nh[i]); + ++fdi; + } + for (i = 0; i != write_nh_len; ++i) + { + fdi->fd = write_nh[i]; + GNUNET_assert (NULL != fdi->fd); + fdi->et = GNUNET_SCHEDULER_ET_OUT; + fdi->sock = GNUNET_NETWORK_get_fd (write_nh[i]); + ++fdi; + } + for (i = 0; i != read_fh_len; ++i) + { + fdi->fh = read_fh[i]; + GNUNET_assert (NULL != fdi->fh); + fdi->et = GNUNET_SCHEDULER_ET_IN; + fdi->sock = (read_fh[i])->fd; // FIXME: does not work under WIN32 + ++fdi; + } + for (i = 0; i != write_fh_len; ++i) + { + fdi->fh = write_fh[i]; + GNUNET_assert (NULL != fdi->fh); + fdi->et = GNUNET_SCHEDULER_ET_OUT; + fdi->sock = (write_fh[i])->fd; // FIXME: does not work under WIN32 + ++fdi; + } + } +} + + +/** + * calls the given function @a func on each FdInfo related to @a t. + * Optionally updates the event type field in each FdInfo after calling + * @a func. + * + * @param t the task + * @param driver_func the function to call with each FdInfo contained in + * in @a t + * @param if_not_ready only call @a driver_func on FdInfos that are not + * ready + * @param et the event type to be set in each FdInfo after calling + * @a driver_func on it, or -1 if no updating not desired. + */ +static void +driver_add_multiple (struct GNUNET_SCHEDULER_Task *t) +{ + struct GNUNET_SCHEDULER_FdInfo *fdi; + int success = GNUNET_YES; + + for (unsigned int i = 0; i != t->fds_len; ++i) + { + fdi = &t->fds[i]; + success = scheduler_driver->add (scheduler_driver->cls, + t, + fdi) && success; + fdi->et = GNUNET_SCHEDULER_ET_NONE; + } + if (GNUNET_YES != success) + { + LOG (GNUNET_ERROR_TYPE_ERROR, + "driver could not add task\n"); + } +} + + +static void +install_parent_control_handler (void *cls) +{ + (void) cls; + install_parent_control_task = NULL; + GNUNET_OS_install_parent_control_handler (NULL); +} + + +static void +shutdown_pipe_cb (void *cls) +{ + char c; + const struct GNUNET_DISK_FileHandle *pr; + + (void) cls; + shutdown_pipe_task = NULL; + pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle, + GNUNET_DISK_PIPE_END_READ); + GNUNET_assert (! GNUNET_DISK_handle_invalid (pr)); + /* consume the signal */ + GNUNET_DISK_file_read (pr, &c, sizeof(c)); + /* mark all active tasks as ready due to shutdown */ + GNUNET_SCHEDULER_shutdown (); + shutdown_pipe_task = + GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL, + pr, + &shutdown_pipe_cb, + NULL); +} + + /** * Cancel the task with the specified identifier. - * The task must not yet have run. + * The task must not yet have run. Only allowed to be called as long as the + * scheduler is running, that is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet * * @param task id of the task to cancel * @return original closure of the task */ void * -GNUNET_SCHEDULER_cancel (GNUNET_SCHEDULER_TaskIdentifier task) +GNUNET_SCHEDULER_cancel (struct GNUNET_SCHEDULER_Task *task) { - struct Task *t; - struct Task *prev; enum GNUNET_SCHEDULER_Priority p; - int to; + int is_fd_task; void *ret; - GNUNET_assert (active_task != NULL); - to = 0; - prev = NULL; - t = pending; - while (t != NULL) - { - if (t->id == task) - break; - prev = t; - t = t->next; - } - if (t == NULL) + LOG (GNUNET_ERROR_TYPE_DEBUG, + "canceling task %p\n", + task); + + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); + is_fd_task = (NULL != task->fds); + if (is_fd_task) { - prev = NULL; - to = 1; - t = pending_timeout; - while (t != NULL) + int del_result = scheduler_driver->del (scheduler_driver->cls, task); + if (GNUNET_OK != del_result) { - if (t->id == task) - break; - prev = t; - t = t->next; + LOG (GNUNET_ERROR_TYPE_ERROR, + "driver could not delete task\n"); + GNUNET_assert (0); } - if (pending_timeout_last == t) - pending_timeout_last = NULL; } - p = 0; - while (t == NULL) + if (! task->in_ready_list) { - p++; - if (p >= GNUNET_SCHEDULER_PRIORITY_COUNT) - { - LOG (GNUNET_ERROR_TYPE_ERROR, _("Attempt to cancel dead task %llu!\n"), - (unsigned long long) task); - GNUNET_assert (0); - } - prev = NULL; - t = ready[p]; - while (t != NULL) + if (is_fd_task) { - if (t->id == task) - { - ready_count--; - break; - } - prev = t; - t = t->next; + GNUNET_CONTAINER_DLL_remove (pending_head, + pending_tail, + task); } - } - if (prev == NULL) - { - if (p == 0) + else if (GNUNET_YES == task->on_shutdown) { - if (to == 0) - { - pending = t->next; - } - else - { - pending_timeout = t->next; - } + GNUNET_CONTAINER_DLL_remove (shutdown_head, + shutdown_tail, + task); } else { - ready[p] = t->next; + GNUNET_CONTAINER_DLL_remove (pending_timeout_head, + pending_timeout_tail, + task); + if (pending_timeout_last == task) + pending_timeout_last = NULL; } } else { - prev->next = t->next; + p = check_priority (task->priority); + GNUNET_CONTAINER_DLL_remove (ready_head[p], + ready_tail[p], + task); + ready_count--; } - ret = t->callback_cls; - LOG (GNUNET_ERROR_TYPE_DEBUG, "Canceling task: %llu / %p\n", task, - t->callback_cls); - destroy_task (t); + ret = task->callback_cls; + destroy_task (task); return ret; } +/** + * Initialize backtrace data for task @a t + * + * @param t task to initialize + */ +static void +init_backtrace (struct GNUNET_SCHEDULER_Task *t) +{ +#if EXECINFO + void *backtrace_array[MAX_TRACE_DEPTH]; + + t->num_backtrace_strings + = backtrace (backtrace_array, MAX_TRACE_DEPTH); + t->backtrace_strings = + backtrace_symbols (backtrace_array, + t->num_backtrace_strings); + dump_backtrace (t); +#else + (void) t; +#endif +} + + /** * Continue the current execution with the given function. This is * similar to the other "add" functions except that there is no delay * and the reason code can be specified. * * @param task main function of the task - * @param task_cls closure for 'main' + * @param task_cls closure for @a task * @param reason reason for task invocation * @param priority priority to use for the task */ void -GNUNET_SCHEDULER_add_continuation_with_priority (GNUNET_SCHEDULER_Task task, void *task_cls, - enum GNUNET_SCHEDULER_Reason reason, - enum GNUNET_SCHEDULER_Priority priority) +GNUNET_SCHEDULER_add_with_reason_and_priority (GNUNET_SCHEDULER_TaskCallback + task, + void *task_cls, + enum GNUNET_SCHEDULER_Reason + reason, + enum GNUNET_SCHEDULER_Priority + priority) { - struct Task *t; - -#if EXECINFO - void *backtrace_array[50]; -#endif + struct GNUNET_SCHEDULER_Task *t; + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); GNUNET_assert (NULL != task); - GNUNET_assert ((active_task != NULL) || - (reason == GNUNET_SCHEDULER_REASON_STARTUP)); - t = GNUNET_malloc (sizeof (struct Task)); -#if EXECINFO - t->num_backtrace_strings = backtrace (backtrace_array, 50); - t->backtrace_strings = - backtrace_symbols (backtrace_array, t->num_backtrace_strings); -#endif + t = GNUNET_new (struct GNUNET_SCHEDULER_Task); t->read_fd = -1; t->write_fd = -1; t->callback = task; t->callback_cls = task_cls; - t->id = ++last_id; #if PROFILE_DELAYS t->start_time = GNUNET_TIME_absolute_get (); #endif t->reason = reason; - t->priority = priority; + t->priority = check_priority (priority); t->lifeness = current_lifeness; - LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding continuation task: %llu / %p\n", t->id, - t->callback_cls); + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Adding continuation task %p\n", + t); + init_backtrace (t); queue_ready_task (t); } /** - * Continue the current execution with the given function. This is - * similar to the other "add" functions except that there is no delay - * and the reason code can be specified. - * - * @param task main function of the task - * @param task_cls closure for 'main' - * @param reason reason for task invocation - */ -void -GNUNET_SCHEDULER_add_continuation (GNUNET_SCHEDULER_Task task, void *task_cls, - enum GNUNET_SCHEDULER_Reason reason) -{ - GNUNET_SCHEDULER_add_continuation_with_priority (task, task_cls, - reason, - GNUNET_SCHEDULER_PRIORITY_DEFAULT); -} - - -/** - * Schedule a new task to be run with a specified priority. - * - * @param prio how important is the new task? - * @param task main function of the task - * @param task_cls closure of task - * @return unique task identifier for the job - * only valid until "task" is started! - */ -GNUNET_SCHEDULER_TaskIdentifier -GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio, - GNUNET_SCHEDULER_Task task, void *task_cls) -{ - return GNUNET_SCHEDULER_add_select (prio, - GNUNET_TIME_UNIT_ZERO, NULL, NULL, task, - task_cls); -} - - - -/** - * Schedule a new task to be run with a specified delay. The task - * will be scheduled for execution once the delay has expired. + * Schedule a new task to be run at the specified time. The task + * will be scheduled for execution at time @a at. * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * @param at time when the operation should run * @param priority priority to use for the task * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier -GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay, - enum GNUNET_SCHEDULER_Priority priority, - GNUNET_SCHEDULER_Task task, void *task_cls) +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_at_with_priority (struct GNUNET_TIME_Absolute at, + enum GNUNET_SCHEDULER_Priority priority, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { - struct Task *t; - struct Task *pos; - struct Task *prev; - -#if EXECINFO - void *backtrace_array[MAX_TRACE_DEPTH]; -#endif + struct GNUNET_SCHEDULER_Task *t; + struct GNUNET_SCHEDULER_Task *pos; + struct GNUNET_SCHEDULER_Task *prev; - GNUNET_assert (active_task != NULL); + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); GNUNET_assert (NULL != task); - t = GNUNET_malloc (sizeof (struct Task)); + t = GNUNET_new (struct GNUNET_SCHEDULER_Task); + GNUNET_async_scope_get (&t->scope); t->callback = task; t->callback_cls = task_cls; -#if EXECINFO - t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH); - t->backtrace_strings = - backtrace_symbols (backtrace_array, t->num_backtrace_strings); -#endif t->read_fd = -1; t->write_fd = -1; - t->id = ++last_id; #if PROFILE_DELAYS t->start_time = GNUNET_TIME_absolute_get (); #endif - t->timeout = GNUNET_TIME_relative_to_absolute (delay); - t->priority = priority; + t->timeout = at; + t->priority = check_priority (priority); t->lifeness = current_lifeness; /* try tail first (optimization in case we are * appending to a long list of tasks with timeouts) */ - prev = pending_timeout_last; - if (prev != NULL) - { - if (prev->timeout.abs_value > t->timeout.abs_value) - prev = NULL; - else - pos = prev->next; /* heuristic success! */ - } - if (prev == NULL) + if ((NULL == pending_timeout_head) || + (at.abs_value_us < pending_timeout_head->timeout.abs_value_us)) { - /* heuristic failed, do traversal of timeout list */ - pos = pending_timeout; + GNUNET_CONTAINER_DLL_insert (pending_timeout_head, + pending_timeout_tail, + t); } - while ((pos != NULL) && - ((pos->timeout.abs_value <= t->timeout.abs_value) || - (pos->reason != 0))) + else { - prev = pos; - pos = pos->next; + /* first move from heuristic start backwards to before start time */ + prev = pending_timeout_last; + while ((NULL != prev) && + (prev->timeout.abs_value_us > t->timeout.abs_value_us)) + prev = prev->prev; + /* now, move from heuristic start (or head of list) forward to insertion point */ + if (NULL == prev) + pos = pending_timeout_head; + else + pos = prev->next; + while ((NULL != pos) && (pos->timeout.abs_value_us <= + t->timeout.abs_value_us)) + { + prev = pos; + pos = pos->next; + } + GNUNET_CONTAINER_DLL_insert_after (pending_timeout_head, + pending_timeout_tail, + prev, + t); } - if (prev == NULL) - pending_timeout = t; - else - prev->next = t; - t->next = pos; - /* hyper-optimization... */ + /* finally, update heuristic insertion point to last insertion... */ pending_timeout_last = t; - LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id, - t->callback_cls); -#if EXECINFO - int i; + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Adding task %p\n", + t); + init_backtrace (t); + return t; +} - for (i = 0; i < t->num_backtrace_strings; i++) - LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i, - t->backtrace_strings[i]); -#endif - return t->id; + +/** + * Schedule a new task to be run with a specified delay. The task + * will be scheduled for execution once the delay has expired. + * + * @param delay when should this operation time out? + * @param priority priority to use for the task + * @param task main function of the task + * @param task_cls closure of @a task + * @return unique task identifier for the job + * only valid until @a task is started! + */ +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay, + enum GNUNET_SCHEDULER_Priority + priority, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) +{ + return GNUNET_SCHEDULER_add_at_with_priority ( + GNUNET_TIME_relative_to_absolute (delay), + priority, + task, + task_cls); +} + + +/** + * Schedule a new task to be run with a specified priority. + * + * @param prio how important is the new task? + * @param task main function of the task + * @param task_cls closure of @a task + * @return unique task identifier for the job + * only valid until @a task is started! + */ +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) +{ + return GNUNET_SCHEDULER_add_delayed_with_priority (GNUNET_TIME_UNIT_ZERO, + prio, + task, + task_cls); +} + + +/** + * Schedule a new task to be run at the specified time. The task + * will be scheduled for execution once specified time has been + * reached. It will be run with the DEFAULT priority. + * + * @param at time at which this operation should run + * @param task main function of the task + * @param task_cls closure of @a task + * @return unique task identifier for the job + * only valid until @a task is started! + */ +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_at (struct GNUNET_TIME_Absolute at, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) +{ + return GNUNET_SCHEDULER_add_at_with_priority (at, + GNUNET_SCHEDULER_PRIORITY_DEFAULT, + task, + task_cls); } @@ -1138,36 +1243,89 @@ GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay, * will be scheduled for execution once the delay has expired. It * will be run with the DEFAULT priority. * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * @param delay when should this operation time out? * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay, - GNUNET_SCHEDULER_Task task, void *task_cls) + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { return GNUNET_SCHEDULER_add_delayed_with_priority (delay, - GNUNET_SCHEDULER_PRIORITY_DEFAULT, - task, task_cls); + GNUNET_SCHEDULER_PRIORITY_DEFAULT, + task, + task_cls); } /** - * Schedule a new task to be run as soon as possible. The task - * will be run with the DEFAULT priority. + * Schedule a new task to be run as soon as possible. Note that this + * does not guarantee that this will be the next task that is being + * run, as other tasks with higher priority (or that are already ready + * to run) might get to run first. Just as with delays, clients must + * not rely on any particular order of execution between tasks + * scheduled concurrently. + * + * The task will be run with the DEFAULT priority. * * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! + */ +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) +{ + return GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_ZERO, + task, + task_cls); +} + + +/** + * Schedule a new task to be run on shutdown, that is when a CTRL-C + * signal is received, or when #GNUNET_SCHEDULER_shutdown() is being + * invoked. + * + * @param task main function of the task + * @param task_cls closure of @a task + * @return unique task identifier for the job + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier -GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_Task task, void *task_cls) +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_shutdown (GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { - return GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_ZERO, task, task_cls); + struct GNUNET_SCHEDULER_Task *t; + + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); + GNUNET_assert (NULL != task); + t = GNUNET_new (struct GNUNET_SCHEDULER_Task); + GNUNET_async_scope_get (&t->scope); + t->callback = task; + t->callback_cls = task_cls; + t->read_fd = -1; + t->write_fd = -1; +#if PROFILE_DELAYS + t->start_time = GNUNET_TIME_absolute_get (); +#endif + t->timeout = GNUNET_TIME_UNIT_FOREVER_ABS; + t->priority = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN; + t->on_shutdown = GNUNET_YES; + t->lifeness = GNUNET_NO; + GNUNET_CONTAINER_DLL_insert (shutdown_head, + shutdown_tail, + t); + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Adding shutdown task %p\n", + t); + init_backtrace (t); + return t; } @@ -1176,32 +1334,57 @@ GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_Task task, void *task_cls) * (transitive) ignore-shutdown flag either explicitly set or * explicitly enabled. This task (and all tasks created from it, * other than by another call to this function) will either count or - * not count for the 'lifeness' of the process. This API is only + * not count for the "lifeness" of the process. This API is only * useful in a few special cases. * - * @param lifeness GNUNET_YES if the task counts for lifeness, GNUNET_NO if not. + * @param lifeness #GNUNET_YES if the task counts for lifeness, #GNUNET_NO if not. * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness, - GNUNET_SCHEDULER_Task task, + GNUNET_SCHEDULER_TaskCallback task, void *task_cls) { - GNUNET_SCHEDULER_TaskIdentifier ret; - - ret = - GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT, - GNUNET_TIME_UNIT_ZERO, NULL, NULL, task, - task_cls); - GNUNET_assert (pending->id == ret); - pending->lifeness = lifeness; + struct GNUNET_SCHEDULER_Task *ret; + + ret = GNUNET_SCHEDULER_add_now (task, task_cls); + ret->lifeness = lifeness; return ret; } +#if DEBUG_FDS +/** + * check a raw file descriptor and abort if it is bad (for debugging purposes) + * + * @param t the task related to the file descriptor + * @param raw_fd the raw file descriptor to check + */ +void +check_fd (struct GNUNET_SCHEDULER_Task *t, int raw_fd) +{ + if (-1 != raw_fd) + { + int flags = fcntl (raw_fd, F_GETFD); + + if ((flags == -1) && (errno == EBADF)) + { + LOG (GNUNET_ERROR_TYPE_ERROR, + "Got invalid file descriptor %d!\n", + raw_fd); + init_backtrace (t); + GNUNET_assert (0); + } + } +} + + +#endif + + /** * Schedule a new task to be run with a specified delay or when any of * the specified file descriptor sets is ready. The delay can be used @@ -1215,103 +1398,68 @@ GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness, * (prerequisite-run) * && (delay-ready * || any-rs-ready - * || any-ws-ready - * || shutdown-active ) + * || any-ws-ready) * * - * @param delay how long should we wait? Use GNUNET_TIME_UNIT_FOREVER_REL for "forever", - * which means that the task will only be run after we receive SIGTERM + * @param delay how long should we wait? * @param priority priority to use * @param rfd file descriptor we want to read (can be -1) * @param wfd file descriptors we want to write (can be -1) * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -#ifndef MINGW -static GNUNET_SCHEDULER_TaskIdentifier -add_without_sets (struct GNUNET_TIME_Relative delay, - enum GNUNET_SCHEDULER_Priority priority, - int rfd, int wfd, - GNUNET_SCHEDULER_Task task, void *task_cls) +static struct GNUNET_SCHEDULER_Task * +add_without_sets (struct GNUNET_TIME_Relative delay, + enum GNUNET_SCHEDULER_Priority priority, + const struct GNUNET_NETWORK_Handle *read_nh, + const struct GNUNET_NETWORK_Handle *write_nh, + const struct GNUNET_DISK_FileHandle *read_fh, + const struct GNUNET_DISK_FileHandle *write_fh, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { - struct Task *t; - -#if EXECINFO - void *backtrace_array[MAX_TRACE_DEPTH]; -#endif + struct GNUNET_SCHEDULER_Task *t; - GNUNET_assert (active_task != NULL); + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); GNUNET_assert (NULL != task); - t = GNUNET_malloc (sizeof (struct Task)); + t = GNUNET_new (struct GNUNET_SCHEDULER_Task); + GNUNET_async_scope_get (&t->scope); + init_fd_info (t, + &read_nh, + read_nh ? 1 : 0, + &write_nh, + write_nh ? 1 : 0, + &read_fh, + read_fh ? 1 : 0, + &write_fh, + write_fh ? 1 : 0); t->callback = task; t->callback_cls = task_cls; -#if EXECINFO - t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH); - t->backtrace_strings = - backtrace_symbols (backtrace_array, t->num_backtrace_strings); -#endif #if DEBUG_FDS - if (-1 != rfd) - { - int flags = fcntl (rfd, F_GETFD); - - if ((flags == -1) && (errno == EBADF)) - { - LOG (GNUNET_ERROR_TYPE_ERROR, "Got invalid file descriptor %d!\n", rfd); -#if EXECINFO - int i; - - for (i = 0; i < t->num_backtrace_strings; i++) - LOG (GNUNET_ERROR_TYPE_DEBUG, "Trace: %s\n", t->backtrace_strings[i]); -#endif - GNUNET_assert (0); - } - } - if (-1 != wfd) - { - int flags = fcntl (wfd, F_GETFD); - - if (flags == -1 && errno == EBADF) - { - LOG (GNUNET_ERROR_TYPE_ERROR, "Got invalid file descriptor %d!\n", wfd); -#if EXECINFO - int i; - - for (i = 0; i < t->num_backtrace_strings; i++) - LOG (GNUNET_ERROR_TYPE_DEBUG, "Trace: %s\n", t->backtrace_strings[i]); -#endif - GNUNET_assert (0); - } - } + check_fd (t, NULL != read_nh ? GNUNET_NETWORK_get_fd (read_nh) : -1); + check_fd (t, NULL != write_nh ? GNUNET_NETWORK_get_fd (write_nh) : -1); + check_fd (t, NULL != read_fh ? read_fh->fd : -1); + check_fd (t, NULL != write_fh ? write_fh->fd : -1); #endif - t->read_fd = rfd; - GNUNET_assert (wfd >= -1); - t->write_fd = wfd; - t->id = ++last_id; #if PROFILE_DELAYS t->start_time = GNUNET_TIME_absolute_get (); #endif t->timeout = GNUNET_TIME_relative_to_absolute (delay); - t->priority = check_priority ((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : priority); + t->priority = check_priority ((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? + current_priority : priority); t->lifeness = current_lifeness; - t->next = pending; - pending = t; - max_priority_added = GNUNET_MAX (max_priority_added, t->priority); - LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id, - t->callback_cls); -#if EXECINFO - int i; - - for (i = 0; i < t->num_backtrace_strings; i++) - LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i, - t->backtrace_strings[i]); -#endif - return t->id; + GNUNET_CONTAINER_DLL_insert (pending_head, + pending_tail, + t); + driver_add_multiple (t); + max_priority_added = GNUNET_MAX (max_priority_added, + t->priority); + init_backtrace (t); + return t; } -#endif - /** @@ -1320,23 +1468,29 @@ add_without_sets (struct GNUNET_TIME_Relative delay, * used as a timeout on the socket being ready. The task will be * scheduled for execution once either the delay has expired or the * socket operation is ready. It will be run with the DEFAULT priority. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet + * + * @param delay when should this operation time out? * @param rfd read file-descriptor * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay, struct GNUNET_NETWORK_Handle *rfd, - GNUNET_SCHEDULER_Task task, void *task_cls) + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { return GNUNET_SCHEDULER_add_read_net_with_priority (delay, - GNUNET_SCHEDULER_PRIORITY_DEFAULT, - rfd, task, task_cls); + GNUNET_SCHEDULER_PRIORITY_DEFAULT, + rfd, task, task_cls); } @@ -1347,45 +1501,37 @@ GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay, * socket being ready. The task will be scheduled for execution once * either the delay has expired or the socket operation is ready. It * will be run with the DEFAULT priority. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet + * + * @param delay when should this operation time out? * @param priority priority to use for the task * @param rfd read file-descriptor * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay, - enum GNUNET_SCHEDULER_Priority priority, - struct GNUNET_NETWORK_Handle *rfd, - GNUNET_SCHEDULER_Task task, void *task_cls) + enum GNUNET_SCHEDULER_Priority + priority, + struct GNUNET_NETWORK_Handle *rfd, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { -#if MINGW - struct GNUNET_NETWORK_FDSet *rs; - GNUNET_SCHEDULER_TaskIdentifier ret; - - GNUNET_assert (rfd != NULL); - rs = GNUNET_NETWORK_fdset_create (); - GNUNET_NETWORK_fdset_set (rs, rfd); - ret = - GNUNET_SCHEDULER_add_select (priority, - delay, rs, NULL, - task, task_cls); - GNUNET_NETWORK_fdset_destroy (rs); - return ret; -#else - return add_without_sets (delay, - priority, - GNUNET_NETWORK_get_fd (rfd), -1, task, - task_cls); -#endif + return GNUNET_SCHEDULER_add_net_with_priority (delay, priority, + rfd, + GNUNET_YES, + GNUNET_NO, + task, task_cls); } - /** * Schedule a new task to be run with a specified delay or when the * specified file descriptor is ready for writing. The delay can be @@ -1393,40 +1539,76 @@ GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay, * scheduled for execution once either the delay has expired or the * socket operation is ready. It will be run with the priority of * the calling task. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * @param delay when should this operation time out? * @param wfd write file-descriptor * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay, struct GNUNET_NETWORK_Handle *wfd, - GNUNET_SCHEDULER_Task task, void *task_cls) + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { -#if MINGW - struct GNUNET_NETWORK_FDSet *ws; - GNUNET_SCHEDULER_TaskIdentifier ret; + return GNUNET_SCHEDULER_add_net_with_priority (delay, + GNUNET_SCHEDULER_PRIORITY_DEFAULT, + wfd, + GNUNET_NO, GNUNET_YES, + task, task_cls); +} - GNUNET_assert (wfd != NULL); - ws = GNUNET_NETWORK_fdset_create (); - GNUNET_NETWORK_fdset_set (ws, wfd); - ret = - GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT, - delay, NULL, ws, - task, task_cls); - GNUNET_NETWORK_fdset_destroy (ws); - return ret; -#else - GNUNET_assert (GNUNET_NETWORK_get_fd (wfd) >= 0); - return add_without_sets (delay, - GNUNET_SCHEDULER_PRIORITY_DEFAULT, - -1, GNUNET_NETWORK_get_fd (wfd), task, - task_cls); -#endif + +/** + * Schedule a new task to be run with a specified delay or when the + * specified file descriptor is ready. The delay can be + * used as a timeout on the socket being ready. The task will be + * scheduled for execution once either the delay has expired or the + * socket operation is ready. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet + * + * @param delay when should this operation time out? + * @param priority priority of the task + * @param fd file-descriptor + * @param on_read whether to poll the file-descriptor for readability + * @param on_write whether to poll the file-descriptor for writability + * @param task main function of the task + * @param task_cls closure of task + * @return unique task identifier for the job + * only valid until "task" is started! + */ +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_net_with_priority (struct GNUNET_TIME_Relative delay, + enum GNUNET_SCHEDULER_Priority priority, + struct GNUNET_NETWORK_Handle *fd, + int on_read, + int on_write, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) +{ + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); + GNUNET_assert (on_read || on_write); + GNUNET_assert (GNUNET_NETWORK_get_fd (fd) >= 0); + return add_without_sets (delay, priority, + on_read ? fd : NULL, + on_write ? fd : NULL, + NULL, + NULL, + task, task_cls); } @@ -1436,42 +1618,30 @@ GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay, * used as a timeout on the socket being ready. The task will be * scheduled for execution once either the delay has expired or the * socket operation is ready. It will be run with the DEFAULT priority. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * @param delay when should this operation time out? * @param rfd read file-descriptor * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay, const struct GNUNET_DISK_FileHandle *rfd, - GNUNET_SCHEDULER_Task task, void *task_cls) + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { -#if MINGW - struct GNUNET_NETWORK_FDSet *rs; - GNUNET_SCHEDULER_TaskIdentifier ret; - - GNUNET_assert (rfd != NULL); - rs = GNUNET_NETWORK_fdset_create (); - GNUNET_NETWORK_fdset_handle_set (rs, rfd); - ret = - GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT, - delay, rs, NULL, - task, task_cls); - GNUNET_NETWORK_fdset_destroy (rs); - return ret; -#else - int fd; - - GNUNET_DISK_internal_file_handle_ (rfd, &fd, sizeof (int)); - return add_without_sets (delay, - GNUNET_SCHEDULER_PRIORITY_DEFAULT, - fd, -1, task, task_cls); - -#endif + return GNUNET_SCHEDULER_add_file_with_priority ( + delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT, + rfd, GNUNET_YES, GNUNET_NO, + task, task_cls); } @@ -1481,46 +1651,129 @@ GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay, * used as a timeout on the socket being ready. The task will be * scheduled for execution once either the delay has expired or the * socket operation is ready. It will be run with the DEFAULT priority. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet * - * @param delay when should this operation time out? Use - * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown" + * @param delay when should this operation time out? * @param wfd write file-descriptor * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay, const struct GNUNET_DISK_FileHandle *wfd, - GNUNET_SCHEDULER_Task task, void *task_cls) + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { -#if MINGW - struct GNUNET_NETWORK_FDSet *ws; - GNUNET_SCHEDULER_TaskIdentifier ret; - - GNUNET_assert (wfd != NULL); - ws = GNUNET_NETWORK_fdset_create (); - GNUNET_NETWORK_fdset_handle_set (ws, wfd); - ret = - GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT, - delay, NULL, ws, - task, task_cls); - GNUNET_NETWORK_fdset_destroy (ws); - return ret; -#else - int fd; + return GNUNET_SCHEDULER_add_file_with_priority ( + delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT, + wfd, GNUNET_NO, GNUNET_YES, + task, task_cls); +} - GNUNET_DISK_internal_file_handle_ (wfd, &fd, sizeof (int)); - GNUNET_assert (fd >= 0); - return add_without_sets (delay, - GNUNET_SCHEDULER_PRIORITY_DEFAULT, - -1, fd, task, task_cls); -#endif +/** + * Schedule a new task to be run with a specified delay or when the + * specified file descriptor is ready. The delay can be + * used as a timeout on the socket being ready. The task will be + * scheduled for execution once either the delay has expired or the + * socket operation is ready. + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet + * + * @param delay when should this operation time out? + * @param priority priority of the task + * @param fd file-descriptor + * @param on_read whether to poll the file-descriptor for readability + * @param on_write whether to poll the file-descriptor for writability + * @param task main function of the task + * @param task_cls closure of @a task + * @return unique task identifier for the job + * only valid until @a task is started! + */ +struct GNUNET_SCHEDULER_Task * +GNUNET_SCHEDULER_add_file_with_priority (struct GNUNET_TIME_Relative delay, + enum GNUNET_SCHEDULER_Priority + priority, + const struct + GNUNET_DISK_FileHandle *fd, + int on_read, int on_write, + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) +{ + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); + GNUNET_assert (on_read || on_write); + GNUNET_assert (fd->fd >= 0); + return add_without_sets (delay, priority, + NULL, + NULL, + on_read ? fd : NULL, + on_write ? fd : NULL, + task, task_cls); } +void +extract_handles (const struct GNUNET_NETWORK_FDSet *fdset, + const struct GNUNET_NETWORK_Handle ***ntarget, + unsigned int *extracted_nhandles, + const struct GNUNET_DISK_FileHandle ***ftarget, + unsigned int *extracted_fhandles) +{ + // FIXME: this implementation only works for unix, for WIN32 the file handles + // in fdset must be handled separately + const struct GNUNET_NETWORK_Handle **nhandles; + const struct GNUNET_DISK_FileHandle **fhandles; + unsigned int nhandles_len; + unsigned int fhandles_len; + + nhandles = NULL; + fhandles = NULL; + nhandles_len = 0; + fhandles_len = 0; + for (int sock = 0; sock != fdset->nsds; ++sock) + { + if (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (fdset, sock)) + { + struct GNUNET_NETWORK_Handle *nhandle; + struct GNUNET_DISK_FileHandle *fhandle; + + nhandle = GNUNET_NETWORK_socket_box_native (sock); + if (NULL != nhandle) + { + GNUNET_array_append (nhandles, nhandles_len, nhandle); + } + else + { + fhandle = GNUNET_DISK_get_handle_from_int_fd (sock); + if (NULL != fhandle) + { + GNUNET_array_append (fhandles, fhandles_len, fhandle); + } + else + { + GNUNET_assert (0); + } + } + } + } + *ntarget = nhandles_len > 0 ? nhandles : NULL; + *ftarget = fhandles_len > 0 ? fhandles : NULL; + *extracted_nhandles = nhandles_len; + *extracted_fhandles = fhandles_len; +} + /** * Schedule a new task to be run with a specified delay or when any of @@ -1535,78 +1788,747 @@ GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay, * (prerequisite-run) * && (delay-ready * || any-rs-ready - * || any-ws-ready - * || (shutdown-active && run-on-shutdown) ) + * || any-ws-ready) ) * + * Only allowed to be called as long as the scheduler is running, that + * is one of the following conditions is met: + * + * - #GNUNET_SCHEDULER_run has been called and has not returned yet + * - #GNUNET_SCHEDULER_driver_init has been run and + * #GNUNET_SCHEDULER_driver_done has not been called yet * * @param prio how important is this task? - * @param delay how long should we wait? Use GNUNET_TIME_UNIT_FOREVER_REL for "forever", - * which means that the task will only be run after we receive SIGTERM + * @param delay how long should we wait? * @param rs set of file descriptors we want to read (can be NULL) * @param ws set of file descriptors we want to write (can be NULL) * @param task main function of the task - * @param task_cls closure of task + * @param task_cls closure of @a task * @return unique task identifier for the job - * only valid until "task" is started! + * only valid until @a task is started! */ -GNUNET_SCHEDULER_TaskIdentifier +struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio, struct GNUNET_TIME_Relative delay, const struct GNUNET_NETWORK_FDSet *rs, const struct GNUNET_NETWORK_FDSet *ws, - GNUNET_SCHEDULER_Task task, void *task_cls) + GNUNET_SCHEDULER_TaskCallback task, + void *task_cls) { - struct Task *t; - -#if EXECINFO - void *backtrace_array[MAX_TRACE_DEPTH]; -#endif - - GNUNET_assert (active_task != NULL); + struct GNUNET_SCHEDULER_Task *t; + const struct GNUNET_NETWORK_Handle **read_nhandles = NULL; + const struct GNUNET_NETWORK_Handle **write_nhandles = NULL; + const struct GNUNET_DISK_FileHandle **read_fhandles = NULL; + const struct GNUNET_DISK_FileHandle **write_fhandles = NULL; + unsigned int read_nhandles_len = 0; + unsigned int write_nhandles_len = 0; + unsigned int read_fhandles_len = 0; + unsigned int write_fhandles_len = 0; + + /* scheduler must be running */ + GNUNET_assert (NULL != scheduler_driver); GNUNET_assert (NULL != task); - t = GNUNET_malloc (sizeof (struct Task)); + int no_rs = (NULL == rs); + int no_ws = (NULL == ws); + int empty_rs = (NULL != rs) && (0 == rs->nsds); + int empty_ws = (NULL != ws) && (0 == ws->nsds); + int no_fds = (no_rs && no_ws) || + (empty_rs && empty_ws) || + (no_rs && empty_ws) || + (no_ws && empty_rs); + if (! no_fds) + { + if (NULL != rs) + { + extract_handles (rs, + &read_nhandles, + &read_nhandles_len, + &read_fhandles, + &read_fhandles_len); + } + if (NULL != ws) + { + extract_handles (ws, + &write_nhandles, + &write_nhandles_len, + &write_fhandles, + &write_fhandles_len); + } + } + /** + * here we consider the case that a GNUNET_NETWORK_FDSet might be empty + * although its maximum FD number (nsds) is greater than 0. We handle + * this case gracefully because some libraries such as libmicrohttpd + * only provide a hint what the maximum FD number in an FD set might be + * and not the exact FD number (see e.g. gnunet-rest-service.c) + */int no_fds_extracted = (0 == read_nhandles_len) && + (0 == read_fhandles_len) && + (0 == write_nhandles_len) && + (0 == write_fhandles_len); + if (no_fds || no_fds_extracted) + return GNUNET_SCHEDULER_add_delayed_with_priority (delay, + prio, + task, + task_cls); + t = GNUNET_new (struct GNUNET_SCHEDULER_Task); + GNUNET_async_scope_get (&t->scope); + init_fd_info (t, + read_nhandles, + read_nhandles_len, + write_nhandles, + write_nhandles_len, + read_fhandles, + read_fhandles_len, + write_fhandles, + write_fhandles_len); t->callback = task; t->callback_cls = task_cls; -#if EXECINFO - t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH); - t->backtrace_strings = - backtrace_symbols (backtrace_array, t->num_backtrace_strings); + t->own_handles = GNUNET_YES; + /* free the arrays of pointers to network / file handles, the actual + * handles will be freed in destroy_task */ + GNUNET_array_grow (read_nhandles, read_nhandles_len, 0); + GNUNET_array_grow (write_nhandles, write_nhandles_len, 0); + GNUNET_array_grow (read_fhandles, read_fhandles_len, 0); + GNUNET_array_grow (write_fhandles, write_fhandles_len, 0); +#if PROFILE_DELAYS + t->start_time = GNUNET_TIME_absolute_get (); #endif - t->read_fd = -1; - t->write_fd = -1; - if (rs != NULL) + t->timeout = GNUNET_TIME_relative_to_absolute (delay); + t->priority = + check_priority ((prio == + GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : + prio); + t->lifeness = current_lifeness; + GNUNET_CONTAINER_DLL_insert (pending_head, + pending_tail, + t); + driver_add_multiple (t); + max_priority_added = GNUNET_MAX (max_priority_added, + t->priority); + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Adding task %p\n", + t); + init_backtrace (t); + return t; +} + + +/** + * Function used by event-loop implementations to signal the scheduler + * that a particular @a task is ready due to an event specified in the + * et field of @a fdi. + * + * This function will then queue the task to notify the application + * that the task is ready (with the respective priority). + * + * @param task the task that is ready + * @param fdi information about the related FD + */ +void +GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task, + struct GNUNET_SCHEDULER_FdInfo *fdi) +{ + enum GNUNET_SCHEDULER_Reason reason; + + reason = task->reason; + if ((0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) && + (0 != (GNUNET_SCHEDULER_ET_IN & fdi->et))) + reason |= GNUNET_SCHEDULER_REASON_READ_READY; + if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) && + (0 != (GNUNET_SCHEDULER_ET_OUT & fdi->et))) + reason |= GNUNET_SCHEDULER_REASON_WRITE_READY; + reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE; + task->reason = reason; + if (GNUNET_NO == task->in_ready_list) { - t->read_set = GNUNET_NETWORK_fdset_create (); - GNUNET_NETWORK_fdset_copy (t->read_set, rs); + GNUNET_CONTAINER_DLL_remove (pending_head, + pending_tail, + task); + queue_ready_task (task); } - if (ws != NULL) +} + + +/** + * Function called by external event loop implementations to tell the + * scheduler to run some of the tasks that are ready. Must be called + * only after #GNUNET_SCHEDULER_driver_init has been called and before + * #GNUNET_SCHEDULER_driver_done is called. + * This function may return even though there are tasks left to run + * just to give other tasks a chance as well. If we return #GNUNET_YES, + * the event loop implementation should call this function again as + * soon as possible, while if we return #GNUNET_NO it must block until + * either the operating system has more work (the scheduler has no more + * work to do right now) or the timeout set by the scheduler (using the + * set_wakeup callback) is reached. + * + * @param sh scheduler handle that was returned by + * #GNUNET_SCHEDULER_driver_init + * @return #GNUNET_YES if there are more tasks that are ready, + * and thus we would like to run more (yield to avoid + * blocking other activities for too long) #GNUNET_NO + * if we are done running tasks (yield to block) + */ +int +GNUNET_SCHEDULER_do_work (struct GNUNET_SCHEDULER_Handle *sh) +{ + enum GNUNET_SCHEDULER_Priority p; + struct GNUNET_SCHEDULER_Task *pos; + struct GNUNET_TIME_Absolute now; + + /* check for tasks that reached the timeout! */ + now = GNUNET_TIME_absolute_get (); + pos = pending_timeout_head; + while (NULL != pos) { - t->write_set = GNUNET_NETWORK_fdset_create (); - GNUNET_NETWORK_fdset_copy (t->write_set, ws); + struct GNUNET_SCHEDULER_Task *next = pos->next; + if (now.abs_value_us >= pos->timeout.abs_value_us) + pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT; + if (0 == pos->reason) + break; + GNUNET_CONTAINER_DLL_remove (pending_timeout_head, + pending_timeout_tail, + pos); + if (pending_timeout_last == pos) + pending_timeout_last = NULL; + queue_ready_task (pos); + pos = next; + } + pos = pending_head; + while (NULL != pos) + { + struct GNUNET_SCHEDULER_Task *next = pos->next; + if (now.abs_value_us >= pos->timeout.abs_value_us) + { + pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT; + GNUNET_CONTAINER_DLL_remove (pending_head, + pending_tail, + pos); + queue_ready_task (pos); + } + pos = next; + } + + if (0 == ready_count) + { + struct GNUNET_TIME_Absolute timeout = get_timeout (); + + if (timeout.abs_value_us > now.abs_value_us) + { + /** + * The event loop called this function before the current timeout was + * reached (and no FD tasks are ready). This is acceptable if + * + * - the system time was changed while the driver was waiting for + * the timeout + * - an external event loop called GNUnet API functions outside of + * the callbacks called in GNUNET_SCHEDULER_do_work and thus + * wasn't notified about the new timeout + * + * It might also mean we are busy-waiting because of a programming + * error in the external event loop. + */LOG (GNUNET_ERROR_TYPE_DEBUG, + "GNUNET_SCHEDULER_do_work did not find any ready " + "tasks and timeout has not been reached yet.\n"); + } + else + { + /** + * the current timeout was reached but no ready tasks were found, + * internal scheduler error! + */ + GNUNET_assert (0); + } } - t->id = ++last_id; + else + { + /* find out which task priority level we are going to + process this time */ + max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP; + GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]); + /* yes, p>0 is correct, 0 is "KEEP" which should + * always be an empty queue (see assertion)! */ + for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--) + { + pos = ready_head[p]; + if (NULL != pos) + break; + } + GNUNET_assert (NULL != pos); /* ready_count wrong? */ + + /* process all tasks at this priority level, then yield */ + while (NULL != (pos = ready_head[p])) + { + GNUNET_CONTAINER_DLL_remove (ready_head[p], + ready_tail[p], + pos); + ready_count--; + current_priority = pos->priority; + current_lifeness = pos->lifeness; + active_task = pos; #if PROFILE_DELAYS - t->start_time = GNUNET_TIME_absolute_get (); + if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us > + DELAY_THRESHOLD.rel_value_us) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Task %p took %s to be scheduled\n", + pos, + GNUNET_STRINGS_relative_time_to_string ( + GNUNET_TIME_absolute_get_duration (pos->start_time), + GNUNET_YES)); + } #endif - t->timeout = GNUNET_TIME_relative_to_absolute (delay); - t->priority = - check_priority ((prio == - GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : - prio); - t->lifeness = current_lifeness; - t->next = pending; - pending = t; - max_priority_added = GNUNET_MAX (max_priority_added, t->priority); - LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id, - t->callback_cls); -#if EXECINFO - int i; + tc.reason = pos->reason; + GNUNET_NETWORK_fdset_zero (sh->rs); + GNUNET_NETWORK_fdset_zero (sh->ws); + // FIXME: do we have to remove FdInfos from fds if they are not ready? + tc.fds_len = pos->fds_len; + tc.fds = pos->fds; + for (unsigned int i = 0; i != pos->fds_len; ++i) + { + struct GNUNET_SCHEDULER_FdInfo *fdi = &pos->fds[i]; + if (0 != (GNUNET_SCHEDULER_ET_IN & fdi->et)) + { + GNUNET_NETWORK_fdset_set_native (sh->rs, + fdi->sock); + } + if (0 != (GNUNET_SCHEDULER_ET_OUT & fdi->et)) + { + GNUNET_NETWORK_fdset_set_native (sh->ws, + fdi->sock); + } + } + tc.read_ready = sh->rs; + tc.write_ready = sh->ws; + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Running task %p\n", + pos); + GNUNET_assert (NULL != pos->callback); + { + struct GNUNET_AsyncScopeSave old_scope; + if (pos->scope.have_scope) + GNUNET_async_scope_enter (&pos->scope.scope_id, &old_scope); + else + GNUNET_async_scope_get (&old_scope); + pos->callback (pos->callback_cls); + GNUNET_async_scope_restore (&old_scope); + } + if (NULL != pos->fds) + { + int del_result = scheduler_driver->del (scheduler_driver->cls, pos); + if (GNUNET_OK != del_result) + { + LOG (GNUNET_ERROR_TYPE_ERROR, + "driver could not delete task %p\n", pos); + GNUNET_assert (0); + } + } + active_task = NULL; + dump_backtrace (pos); + destroy_task (pos); + } + } + shutdown_if_no_lifeness (); + if (0 == ready_count) + { + scheduler_driver->set_wakeup (scheduler_driver->cls, + get_timeout ()); + return GNUNET_NO; + } + scheduler_driver->set_wakeup (scheduler_driver->cls, + GNUNET_TIME_absolute_get ()); + return GNUNET_YES; +} - for (i = 0; i < t->num_backtrace_strings; i++) - LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i, - t->backtrace_strings[i]); + +/** + * Function called by external event loop implementations to initialize + * the scheduler. An external implementation has to provide @a driver + * which contains callbacks for the scheduler (see definition of struct + * #GNUNET_SCHEDULER_Driver). The callbacks are used to instruct the + * external implementation to watch for events. If it detects any of + * those events it is expected to call #GNUNET_SCHEDULER_do_work to let + * the scheduler handle it. If an event is related to a specific task + * (e.g. the scheduler gave instructions to watch a file descriptor), + * the external implementation is expected to mark that task ready + * before by calling #GNUNET_SCHEDULER_task_ready. + + * This function has to be called before any tasks are scheduled and + * before GNUNET_SCHEDULER_do_work is called for the first time. It + * allocates resources that have to be freed again by calling + * #GNUNET_SCHEDULER_driver_done. + * + * This function installs the same signal handlers as + * #GNUNET_SCHEDULER_run. This means SIGTERM (and other similar signals) + * will induce a call to #GNUNET_SCHEDULER_shutdown during the next + * call to #GNUNET_SCHEDULER_do_work. As a result, SIGTERM causes all + * active tasks to be scheduled with reason + * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added afterwards + * will execute normally!). Note that any particular signal will only + * shut down one scheduler; applications should always only create a + * single scheduler. + * + * @param driver to use for the event loop + * @return handle to be passed to #GNUNET_SCHEDULER_do_work and + * #GNUNET_SCHEDULER_driver_done + */ +struct GNUNET_SCHEDULER_Handle * +GNUNET_SCHEDULER_driver_init (const struct GNUNET_SCHEDULER_Driver *driver) +{ + struct GNUNET_SCHEDULER_Handle *sh; + const struct GNUNET_DISK_FileHandle *pr; + + /* scheduler must not be running */ + GNUNET_assert (NULL == scheduler_driver); + GNUNET_assert (NULL == shutdown_pipe_handle); + /* general set-up */ + sh = GNUNET_new (struct GNUNET_SCHEDULER_Handle); + shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO, + GNUNET_NO, + GNUNET_NO, + GNUNET_NO); + GNUNET_assert (NULL != shutdown_pipe_handle); + pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle, + GNUNET_DISK_PIPE_END_READ); + my_pid = getpid (); + scheduler_driver = driver; + + /* install signal handlers */ + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Registering signal handlers\n"); + sh->shc_int = GNUNET_SIGNAL_handler_install (SIGINT, + &sighandler_shutdown); + sh->shc_term = GNUNET_SIGNAL_handler_install (SIGTERM, + &sighandler_shutdown); +#if (SIGTERM != GNUNET_TERM_SIG) + sh->shc_gterm = GNUNET_SIGNAL_handler_install (GNUNET_TERM_SIG, + &sighandler_shutdown); +#endif + sh->shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE, + &sighandler_pipe); + sh->shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT, + &sighandler_shutdown); + sh->shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP, + &sighandler_shutdown); + + /* Setup initial tasks */ + current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT; + current_lifeness = GNUNET_NO; + install_parent_control_task = + GNUNET_SCHEDULER_add_now (&install_parent_control_handler, + NULL); + shutdown_pipe_task = + GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL, + pr, + &shutdown_pipe_cb, + NULL); + current_lifeness = GNUNET_YES; + scheduler_driver->set_wakeup (scheduler_driver->cls, + get_timeout ()); + /* begin main event loop */ + sh->rs = GNUNET_NETWORK_fdset_create (); + sh->ws = GNUNET_NETWORK_fdset_create (); + GNUNET_NETWORK_fdset_handle_set (sh->rs, pr); + return sh; +} + + +/** + * Counter-part of #GNUNET_SCHEDULER_driver_init. Has to be called + * by external event loop implementations after the scheduler has + * shut down. This is the case if both of the following conditions + * are met: + * + * - all tasks the scheduler has added through the driver's add + * callback have been removed again through the driver's del + * callback + * - the timeout the scheduler has set through the driver's + * add_wakeup callback is FOREVER + * + * @param sh the handle returned by #GNUNET_SCHEDULER_driver_init + */ +void +GNUNET_SCHEDULER_driver_done (struct GNUNET_SCHEDULER_Handle *sh) +{ + GNUNET_assert (NULL == pending_head); + GNUNET_assert (NULL == pending_timeout_head); + GNUNET_assert (NULL == shutdown_head); + for (int i = 0; i != GNUNET_SCHEDULER_PRIORITY_COUNT; ++i) + { + GNUNET_assert (NULL == ready_head[i]); + } + GNUNET_NETWORK_fdset_destroy (sh->rs); + GNUNET_NETWORK_fdset_destroy (sh->ws); + + /* uninstall signal handlers */ + GNUNET_SIGNAL_handler_uninstall (sh->shc_int); + GNUNET_SIGNAL_handler_uninstall (sh->shc_term); +#if (SIGTERM != GNUNET_TERM_SIG) + GNUNET_SIGNAL_handler_uninstall (sh->shc_gterm); #endif - return t->id; + GNUNET_SIGNAL_handler_uninstall (sh->shc_pipe); + GNUNET_SIGNAL_handler_uninstall (sh->shc_quit); + GNUNET_SIGNAL_handler_uninstall (sh->shc_hup); + GNUNET_DISK_pipe_close (shutdown_pipe_handle); + shutdown_pipe_handle = NULL; + scheduler_driver = NULL; + GNUNET_free (sh); } + +static int +select_loop (struct GNUNET_SCHEDULER_Handle *sh, + struct DriverContext *context) +{ + struct GNUNET_NETWORK_FDSet *rs; + struct GNUNET_NETWORK_FDSet *ws; + int select_result; + + GNUNET_assert (NULL != context); + rs = GNUNET_NETWORK_fdset_create (); + ws = GNUNET_NETWORK_fdset_create (); + while ((NULL != context->scheduled_head) || + (GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us != + context->timeout.abs_value_us)) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "select timeout = %s\n", + GNUNET_STRINGS_absolute_time_to_string (context->timeout)); + + GNUNET_NETWORK_fdset_zero (rs); + GNUNET_NETWORK_fdset_zero (ws); + + for (struct Scheduled *pos = context->scheduled_head; + NULL != pos; + pos = pos->next) + { + if (0 != (GNUNET_SCHEDULER_ET_IN & pos->et)) + { + GNUNET_NETWORK_fdset_set_native (rs, pos->fdi->sock); + } + if (0 != (GNUNET_SCHEDULER_ET_OUT & pos->et)) + { + GNUNET_NETWORK_fdset_set_native (ws, pos->fdi->sock); + } + } + struct GNUNET_TIME_Relative time_remaining = + GNUNET_TIME_absolute_get_remaining (context->timeout); + if (NULL == scheduler_select) + { + select_result = GNUNET_NETWORK_socket_select (rs, + ws, + NULL, + time_remaining); + } + else + { + select_result = scheduler_select (scheduler_select_cls, + rs, + ws, + NULL, + time_remaining); + } + if (select_result == GNUNET_SYSERR) + { + if (errno == EINTR) + continue; + + LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, + "select"); +#if USE_LSOF + char lsof[512]; + + snprintf (lsof, + sizeof(lsof), + "lsof -p %d", + getpid ()); + (void) close (1); + (void) dup2 (2, 1); + if (0 != system (lsof)) + LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING, + "system"); +#endif +#if DEBUG_FDS + for (struct Scheduled *s = context->scheduled_head; + NULL != s; + s = s->next) + { + int flags = fcntl (s->fdi->sock, + F_GETFD); + + if ((flags == -1) && + (EBADF == errno)) + { + LOG (GNUNET_ERROR_TYPE_ERROR, + "Got invalid file descriptor %d!\n", + s->fdi->sock); +#if EXECINFO + dump_backtrace (s->task); +#endif + } + } +#endif + GNUNET_assert (0); + GNUNET_NETWORK_fdset_destroy (rs); + GNUNET_NETWORK_fdset_destroy (ws); + return GNUNET_SYSERR; + } + if (select_result > 0) + { + for (struct Scheduled *pos = context->scheduled_head; + NULL != pos; + pos = pos->next) + { + int is_ready = GNUNET_NO; + + if ((0 != (GNUNET_SCHEDULER_ET_IN & pos->et)) && + (GNUNET_YES == + GNUNET_NETWORK_fdset_test_native (rs, + pos->fdi->sock)) ) + { + pos->fdi->et |= GNUNET_SCHEDULER_ET_IN; + is_ready = GNUNET_YES; + } + if ((0 != (GNUNET_SCHEDULER_ET_OUT & pos->et)) && + (GNUNET_YES == + GNUNET_NETWORK_fdset_test_native (ws, + pos->fdi->sock)) ) + { + pos->fdi->et |= GNUNET_SCHEDULER_ET_OUT; + is_ready = GNUNET_YES; + } + if (GNUNET_YES == is_ready) + { + GNUNET_SCHEDULER_task_ready (pos->task, + pos->fdi); + } + } + } + if (GNUNET_YES == GNUNET_SCHEDULER_do_work (sh)) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "scheduler has more tasks ready!\n"); + } + } + GNUNET_NETWORK_fdset_destroy (rs); + GNUNET_NETWORK_fdset_destroy (ws); + return GNUNET_OK; +} + + +static int +select_add (void *cls, + struct GNUNET_SCHEDULER_Task *task, + struct GNUNET_SCHEDULER_FdInfo *fdi) +{ + struct DriverContext *context = cls; + + GNUNET_assert (NULL != context); + GNUNET_assert (NULL != task); + GNUNET_assert (NULL != fdi); + GNUNET_assert (0 != (GNUNET_SCHEDULER_ET_IN & fdi->et) || + 0 != (GNUNET_SCHEDULER_ET_OUT & fdi->et)); + + if (! ((NULL != fdi->fd) ^ (NULL != fdi->fh)) || (fdi->sock < 0)) + { + /* exactly one out of {fd, hf} must be != NULL and the OS handle must be valid */ + return GNUNET_SYSERR; + } + + struct Scheduled *scheduled = GNUNET_new (struct Scheduled); + scheduled->task = task; + scheduled->fdi = fdi; + scheduled->et = fdi->et; + + GNUNET_CONTAINER_DLL_insert (context->scheduled_head, + context->scheduled_tail, + scheduled); + return GNUNET_OK; +} + + +static int +select_del (void *cls, + struct GNUNET_SCHEDULER_Task *task) +{ + struct DriverContext *context; + struct Scheduled *pos; + int ret; + + GNUNET_assert (NULL != cls); + + context = cls; + ret = GNUNET_SYSERR; + pos = context->scheduled_head; + while (NULL != pos) + { + struct Scheduled *next = pos->next; + if (pos->task == task) + { + GNUNET_CONTAINER_DLL_remove (context->scheduled_head, + context->scheduled_tail, + pos); + GNUNET_free (pos); + ret = GNUNET_OK; + } + pos = next; + } + return ret; +} + + +static void +select_set_wakeup (void *cls, + struct GNUNET_TIME_Absolute dt) +{ + struct DriverContext *context = cls; + + GNUNET_assert (NULL != context); + context->timeout = dt; +} + + +/** + * Obtain the driver for using select() as the event loop. + * + * @return NULL on error + */ +struct GNUNET_SCHEDULER_Driver * +GNUNET_SCHEDULER_driver_select () +{ + struct GNUNET_SCHEDULER_Driver *select_driver; + + select_driver = GNUNET_new (struct GNUNET_SCHEDULER_Driver); + + select_driver->add = &select_add; + select_driver->del = &select_del; + select_driver->set_wakeup = &select_set_wakeup; + + return select_driver; +} + + +/** + * Change the async scope for the currently executing task and (transitively) + * for all tasks scheduled by the current task after calling this function. + * Nested tasks can begin their own nested async scope. + * + * Once the current task is finished, the async scope ID is reset to + * its previous value. + * + * Must only be called from a running task. + * + * @param aid the asynchronous scope id to enter + */ +void +GNUNET_SCHEDULER_begin_async_scope (struct GNUNET_AsyncScopeId *aid) +{ + struct GNUNET_AsyncScopeSave dummy_old_scope; + + GNUNET_assert (NULL != active_task); + /* Since we're in a task, the context will be automatically + restored by the scheduler. */ + GNUNET_async_scope_enter (aid, &dummy_old_scope); +} + + /* end of scheduler.c */