/*
This file is part of GNUnet.
- (C) 2011, 2012 Christian Grothoff
+ Copyright (C) 2011, 2012 Christian Grothoff
- 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 3, 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 <http://www.gnu.org/licenses/>.
+
+ SPDX-License-Identifier: AGPL3.0-or-later
+ */
/**
* @file util/helper.c
- * @brief API for dealing with (SUID) helper processes that communicate via GNUNET_MessageHeaders on stdin/stdout
+ * @brief API for dealing with (SUID) helper processes that communicate via
+ * GNUNET_MessageHeaders on stdin/stdout
* @author Philipp Toelke
* @author Christian Grothoff
*/
#include "platform.h"
#include "gnunet_util_lib.h"
+#include "gnunet_mst_lib.h"
/**
* Entry in the queue of messages we need to transmit to the helper.
*/
-struct HelperMessageQueueEntry
-{
-
+struct GNUNET_HELPER_SendHandle {
/**
* This is an entry in a DLL.
*/
- struct HelperMessageQueueEntry *next;
+ struct GNUNET_HELPER_SendHandle *next;
/**
* This is an entry in a DLL.
*/
- struct HelperMessageQueueEntry *prev;
+ struct GNUNET_HELPER_SendHandle *prev;
/**
* Message to transmit (allocated at the end of this struct)
*/
const struct GNUNET_MessageHeader *msg;
-
+
+ /**
+ * The handle to a helper process.
+ */
+ struct GNUNET_HELPER_Handle *h;
+
/**
* Function to call upon completion.
*/
* Current write position.
*/
unsigned int wpos;
-
};
/**
* The handle to a helper process.
*/
-struct GNUNET_HELPER_Handle
-{
-
+struct GNUNET_HELPER_Handle {
/**
* PipeHandle to receive data from the helper
*/
struct GNUNET_DISK_PipeHandle *helper_in;
-
+
/**
* PipeHandle to send data to the helper
*/
struct GNUNET_DISK_PipeHandle *helper_out;
-
+
/**
* FileHandle to receive data from the helper
*/
const struct GNUNET_DISK_FileHandle *fh_from_helper;
-
+
/**
* FileHandle to send data to the helper
*/
const struct GNUNET_DISK_FileHandle *fh_to_helper;
-
+
/**
* The process id of the helper
*/
/**
* The Message-Tokenizer that tokenizes the messages comming from the helper
*/
- struct GNUNET_SERVER_MessageStreamTokenizer *mst;
+ struct GNUNET_MessageStreamTokenizer *mst;
+
+ /**
+ * The exception callback
+ */
+ GNUNET_HELPER_ExceptionCallback exp_cb;
+
+ /**
+ * The closure for callbacks
+ */
+ void *cb_cls;
/**
* First message queued for transmission to helper.
*/
- struct HelperMessageQueueEntry *mq_head;
+ struct GNUNET_HELPER_SendHandle *sh_head;
/**
* Last message queued for transmission to helper.
*/
- struct HelperMessageQueueEntry *mq_tail;
+ struct GNUNET_HELPER_SendHandle *sh_tail;
/**
* Binary to run.
*/
- const char *binary_name;
+ char *binary_name;
/**
* NULL-terminated list of command-line arguments.
*/
- char *const *binary_argv;
-
+ char **binary_argv;
+
/**
* Task to read from the helper.
*/
- GNUNET_SCHEDULER_TaskIdentifier read_task;
+ struct GNUNET_SCHEDULER_Task *read_task;
/**
* Task to read from the helper.
*/
- GNUNET_SCHEDULER_TaskIdentifier write_task;
+ struct GNUNET_SCHEDULER_Task *write_task;
/**
* Restart task.
*/
- GNUNET_SCHEDULER_TaskIdentifier restart_task;
+ struct GNUNET_SCHEDULER_Task *restart_task;
+
+ /**
+ * Does the helper support the use of a control pipe for signalling?
+ */
+ int with_control_pipe;
+
+ /**
+ * Count start attempts to increase linear back off
+ */
+ unsigned int retry_back_off;
};
/**
- * Stop the helper process, we're closing down or had an error.
+ * Sends termination signal to the helper process. The helper process is not
+ * reaped; call GNUNET_HELPER_wait() for reaping the dead helper process.
*
- * @param h handle to the helper process
+ * @param h the helper handle
+ * @param soft_kill if GNUNET_YES, signals termination by closing the helper's
+ * stdin; GNUNET_NO to signal termination by sending SIGTERM to helper
+ * @return #GNUNET_OK on success; #GNUNET_SYSERR on error
*/
-static void
-stop_helper (struct GNUNET_HELPER_Handle *h)
+int
+GNUNET_HELPER_kill(struct GNUNET_HELPER_Handle *h, int soft_kill)
+{
+ struct GNUNET_HELPER_SendHandle *sh;
+ int ret;
+
+ while (NULL != (sh = h->sh_head))
+ {
+ GNUNET_CONTAINER_DLL_remove(h->sh_head, h->sh_tail, sh);
+ if (NULL != sh->cont)
+ sh->cont(sh->cont_cls, GNUNET_NO);
+ GNUNET_free(sh);
+ }
+ if (NULL != h->restart_task)
+ {
+ GNUNET_SCHEDULER_cancel(h->restart_task);
+ h->restart_task = NULL;
+ }
+ if (NULL != h->read_task)
+ {
+ GNUNET_SCHEDULER_cancel(h->read_task);
+ h->read_task = NULL;
+ }
+ if (NULL == h->helper_proc)
+ return GNUNET_SYSERR;
+ if (GNUNET_YES == soft_kill)
+ {
+ /* soft-kill only possible with pipes */
+ GNUNET_assert(NULL != h->helper_in);
+ ret = GNUNET_DISK_pipe_close(h->helper_in);
+ h->helper_in = NULL;
+ h->fh_to_helper = NULL;
+ return ret;
+ }
+ if (0 != GNUNET_OS_process_kill(h->helper_proc, GNUNET_TERM_SIG))
+ return GNUNET_SYSERR;
+ return GNUNET_OK;
+}
+
+
+/**
+ * Reap the helper process. This call is blocking(!). The helper process
+ * should either be sent a termination signal before or should be dead before
+ * calling this function
+ *
+ * @param h the helper handle
+ * @return #GNUNET_OK on success; #GNUNET_SYSERR on error
+ */
+int
+GNUNET_HELPER_wait(struct GNUNET_HELPER_Handle *h)
{
- struct HelperMessageQueueEntry *qe;
+ struct GNUNET_HELPER_SendHandle *sh;
+ int ret;
+ ret = GNUNET_SYSERR;
if (NULL != h->helper_proc)
- {
- GNUNET_OS_process_kill (h->helper_proc, SIGKILL);
- GNUNET_OS_process_wait (h->helper_proc);
- GNUNET_OS_process_close (h->helper_proc);
- h->helper_proc = NULL;
- }
- if (GNUNET_SCHEDULER_NO_TASK != h->restart_task)
- {
- GNUNET_SCHEDULER_cancel (h->restart_task);
- h->restart_task = GNUNET_SCHEDULER_NO_TASK;
- }
- if (GNUNET_SCHEDULER_NO_TASK != h->read_task)
- {
- GNUNET_SCHEDULER_cancel (h->read_task);
- h->read_task = GNUNET_SCHEDULER_NO_TASK;
- }
- if (GNUNET_SCHEDULER_NO_TASK != h->write_task)
- {
- GNUNET_SCHEDULER_cancel (h->write_task);
- h->write_task = GNUNET_SCHEDULER_NO_TASK;
- }
+ {
+ ret = GNUNET_OS_process_wait(h->helper_proc);
+ GNUNET_OS_process_destroy(h->helper_proc);
+ h->helper_proc = NULL;
+ }
+ if (NULL != h->read_task)
+ {
+ GNUNET_SCHEDULER_cancel(h->read_task);
+ h->read_task = NULL;
+ }
+ if (NULL != h->write_task)
+ {
+ GNUNET_SCHEDULER_cancel(h->write_task);
+ h->write_task = NULL;
+ }
if (NULL != h->helper_in)
- {
- GNUNET_DISK_pipe_close (h->helper_in);
- h->helper_in = NULL;
- h->fh_to_helper = NULL;
- }
+ {
+ GNUNET_DISK_pipe_close(h->helper_in);
+ h->helper_in = NULL;
+ h->fh_to_helper = NULL;
+ }
if (NULL != h->helper_out)
- {
- GNUNET_DISK_pipe_close (h->helper_out);
- h->helper_out = NULL;
- h->fh_from_helper = NULL;
- }
- while (NULL != (qe = h->mq_head))
- {
- GNUNET_CONTAINER_DLL_remove (h->mq_head,
- h->mq_tail,
- qe);
- qe->cont (qe->cont_cls, GNUNET_NO);
- GNUNET_free (qe);
- }
+ {
+ GNUNET_DISK_pipe_close(h->helper_out);
+ h->helper_out = NULL;
+ h->fh_from_helper = NULL;
+ }
+ while (NULL != (sh = h->sh_head))
+ {
+ GNUNET_CONTAINER_DLL_remove(h->sh_head, h->sh_tail, sh);
+ if (NULL != sh->cont)
+ sh->cont(sh->cont_cls, GNUNET_NO);
+ GNUNET_free(sh);
+ }
/* purge MST buffer */
- GNUNET_SERVER_mst_receive (h->mst, NULL, NULL, 0, GNUNET_YES, GNUNET_NO);
+ if (NULL != h->mst)
+ (void)GNUNET_MST_from_buffer(h->mst, NULL, 0, GNUNET_YES, GNUNET_NO);
+ return ret;
+}
+
+
+/**
+ * Stop the helper process, we're closing down or had an error.
+ *
+ * @param h handle to the helper process
+ * @param soft_kill if #GNUNET_YES, signals termination by closing the helper's
+ * stdin; #GNUNET_NO to signal termination by sending SIGTERM to helper
+ */
+static void
+stop_helper(struct GNUNET_HELPER_Handle *h, int soft_kill)
+{
+ if (NULL != h->restart_task)
+ {
+ GNUNET_SCHEDULER_cancel(h->restart_task);
+ h->restart_task = NULL;
+ }
+ else
+ {
+ GNUNET_break(GNUNET_OK == GNUNET_HELPER_kill(h, soft_kill));
+ GNUNET_break(GNUNET_OK == GNUNET_HELPER_wait(h));
+ }
}
* Restart the helper process.
*
* @param cls handle to the helper process
- * @param tc scheduler context
*/
static void
-restart_task (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc);
+restart_task(void *cls);
/**
* Read from the helper-process
*
* @param cls handle to the helper process
- * @param tc scheduler context
*/
static void
-helper_read (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tsdkctx)
+helper_read(void *cls)
{
- struct GNUNET_HELPER_Handle*h = cls;
- char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE];
+ struct GNUNET_HELPER_Handle *h = cls;
+ char buf[GNUNET_MAX_MESSAGE_SIZE] GNUNET_ALIGN;
ssize_t t;
- h->read_task = GNUNET_SCHEDULER_NO_TASK;
- if (0 != (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
- {
- /* try again */
- h->read_task = GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
- h->fh_from_helper, &helper_read, h);
- return;
- }
- t = GNUNET_DISK_file_read (h->fh_from_helper, &buf, sizeof (buf));
- if (t <= 0)
- {
- /* On read-error, restart the helper */
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- _("Error reading from `%s': %s\n"),
- h->binary_name,
- STRERROR (errno));
- stop_helper (h);
- /* Restart the helper */
- h->restart_task =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
- &restart_task, h);
- return;
- }
+ h->read_task = NULL;
+ t = GNUNET_DISK_file_read(h->fh_from_helper, &buf, sizeof(buf));
+ if (t < 0)
+ {
+ /* On read-error, restart the helper */
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
+ _("Error reading from `%s': %s\n"),
+ h->binary_name,
+ strerror(errno));
+ if (NULL != h->exp_cb)
+ {
+ h->exp_cb(h->cb_cls);
+ GNUNET_HELPER_stop(h, GNUNET_NO);
+ return;
+ }
+ stop_helper(h, GNUNET_NO);
+ /* Restart the helper */
+ h->restart_task = GNUNET_SCHEDULER_add_delayed(
+ GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ h->retry_back_off),
+ &restart_task,
+ h);
+ return;
+ }
+ if (0 == t)
+ {
+ /* this happens if the helper is shut down via a
+ signal, so it is not a "hard" error */
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got 0 bytes from helper `%s' (EOF)\n",
+ h->binary_name);
+ if (NULL != h->exp_cb)
+ {
+ h->exp_cb(h->cb_cls);
+ GNUNET_HELPER_stop(h, GNUNET_NO);
+ return;
+ }
+ stop_helper(h, GNUNET_NO);
+ /* Restart the helper */
+ h->restart_task = GNUNET_SCHEDULER_add_delayed(
+ GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ h->retry_back_off),
+ &restart_task,
+ h);
+ return;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got %u bytes from helper `%s'\n",
+ (unsigned int)t,
+ h->binary_name);
+ h->read_task = GNUNET_SCHEDULER_add_read_file(GNUNET_TIME_UNIT_FOREVER_REL,
+ h->fh_from_helper,
+ &helper_read,
+ h);
if (GNUNET_SYSERR ==
- GNUNET_SERVER_mst_receive (h->mst, NULL, buf, t, GNUNET_NO, GNUNET_NO))
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- _("Failed to parse inbound message from helper `%s'\n"),
- h->binary_name);
- stop_helper (h);
- /* Restart the helper */
- h->restart_task =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
- &restart_task, h);
- return;
-
- }
- h->read_task = GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
- h->fh_from_helper, &helper_read, h);
+ GNUNET_MST_from_buffer(h->mst, buf, t, GNUNET_NO, GNUNET_NO))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to parse inbound message from helper `%s'\n"),
+ h->binary_name);
+ if (NULL != h->exp_cb)
+ {
+ h->exp_cb(h->cb_cls);
+ GNUNET_HELPER_stop(h, GNUNET_NO);
+ return;
+ }
+ stop_helper(h, GNUNET_NO);
+ /* Restart the helper */
+ h->restart_task = GNUNET_SCHEDULER_add_delayed(
+ GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ h->retry_back_off),
+ &restart_task,
+ h);
+ return;
+ }
}
* @param h handle to the helper process
*/
static void
-start_helper (struct GNUNET_HELPER_Handle *h)
+start_helper(struct GNUNET_HELPER_Handle *h)
{
- h->helper_in = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO);
- h->helper_out = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_NO, GNUNET_YES);
- if ( (h->helper_in == NULL) || (h->helper_out == NULL))
- {
- /* out of file descriptors? try again later... */
- stop_helper (h);
- h->restart_task =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
- &restart_task, h);
- return;
- }
+ h->helper_in =
+ GNUNET_DISK_pipe(GNUNET_YES, GNUNET_YES, GNUNET_YES, GNUNET_NO);
+ h->helper_out =
+ GNUNET_DISK_pipe(GNUNET_YES, GNUNET_YES, GNUNET_NO, GNUNET_YES);
+ if ((h->helper_in == NULL) || (h->helper_out == NULL))
+ {
+ /* out of file descriptors? try again later... */
+ stop_helper(h, GNUNET_NO);
+ h->restart_task = GNUNET_SCHEDULER_add_delayed(
+ GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ h->retry_back_off),
+ &restart_task,
+ h);
+ return;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Starting HELPER process `%s'\n",
+ h->binary_name);
h->fh_from_helper =
- GNUNET_DISK_pipe_handle (h->helper_out, GNUNET_DISK_PIPE_END_READ);
- GNUNET_DISK_pipe_close_end (h->helper_out, GNUNET_DISK_PIPE_END_WRITE);
+ GNUNET_DISK_pipe_handle(h->helper_out, GNUNET_DISK_PIPE_END_READ);
h->fh_to_helper =
- GNUNET_DISK_pipe_handle (h->helper_in, GNUNET_DISK_PIPE_END_WRITE);
- GNUNET_DISK_pipe_close_end (h->helper_in, GNUNET_DISK_PIPE_END_READ);
- h->helper_proc =
- GNUNET_OS_start_process_vap (h->helper_in, h->helper_out,
- h->binary_name,
- h->binary_argv);
+ GNUNET_DISK_pipe_handle(h->helper_in, GNUNET_DISK_PIPE_END_WRITE);
+ h->helper_proc = GNUNET_OS_start_process_vap(h->with_control_pipe,
+ GNUNET_OS_INHERIT_STD_ERR,
+ h->helper_in,
+ h->helper_out,
+ NULL,
+ h->binary_name,
+ h->binary_argv);
if (NULL == h->helper_proc)
- {
- /* failed to start process? try again later... */
- stop_helper (h);
- h->restart_task =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
- &restart_task, h);
- return;
- }
- h->read_task = GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
- h->fh_from_helper,
- &helper_read,
- h);
+ {
+ /* failed to start process? try again later... */
+ stop_helper(h, GNUNET_NO);
+ h->restart_task = GNUNET_SCHEDULER_add_delayed(
+ GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ h->retry_back_off),
+ &restart_task,
+ h);
+ return;
+ }
+ GNUNET_DISK_pipe_close_end(h->helper_out, GNUNET_DISK_PIPE_END_WRITE);
+ GNUNET_DISK_pipe_close_end(h->helper_in, GNUNET_DISK_PIPE_END_READ);
+ if (NULL != h->mst)
+ h->read_task = GNUNET_SCHEDULER_add_read_file(GNUNET_TIME_UNIT_FOREVER_REL,
+ h->fh_from_helper,
+ &helper_read,
+ h);
}
* Restart the helper process.
*
* @param cls handle to the helper process
- * @param tc scheduler context
*/
static void
-restart_task (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+restart_task(void *cls)
{
- struct GNUNET_HELPER_Handle*h = cls;
+ struct GNUNET_HELPER_Handle *h = cls;
- h->restart_task = GNUNET_SCHEDULER_NO_TASK;
- start_helper (h);
+ h->restart_task = NULL;
+ h->retry_back_off++;
+ GNUNET_log(GNUNET_ERROR_TYPE_INFO,
+ "Restarting helper with back-off %u\n",
+ h->retry_back_off);
+ start_helper(h);
}
/**
- * @brief Starts a helper and begins reading from it
+ * Starts a helper and begins reading from it. The helper process is
+ * restarted when it dies except when it is stopped using GNUNET_HELPER_stop()
+ * or when the exp_cb callback is not NULL.
*
+ * @param with_control_pipe does the helper support the use of a control pipe for signalling?
* @param binary_name name of the binary to run
* @param binary_argv NULL-terminated list of arguments to give when starting the binary (this
* argument must not be modified by the client for
- * the lifetime of the helper h)
+ * the lifetime of the helper handle)
* @param cb function to call if we get messages from the helper
- * @param cb_cls Closure for the callback
- * @return the new H, NULL on error
+ * @param exp_cb the exception callback to call. Set this to NULL if the helper
+ * process has to be restarted automatically when it dies/crashes
+ * @param cb_cls closure for the above callback
+ * @return the new Handle, NULL on error
*/
-struct GNUNET_HELPER_Handle*
-GNUNET_HELPER_start (const char *binary_name,
- char *const binary_argv[],
- GNUNET_SERVER_MessageTokenizerCallback cb, void *cb_cls)
+struct GNUNET_HELPER_Handle *
+GNUNET_HELPER_start(int with_control_pipe,
+ const char *binary_name,
+ char *const binary_argv[],
+ GNUNET_MessageTokenizerCallback cb,
+ GNUNET_HELPER_ExceptionCallback exp_cb,
+ void *cb_cls)
{
- struct GNUNET_HELPER_Handle*h;
-
- h = GNUNET_malloc (sizeof (struct GNUNET_HELPER_Handle));
- h->binary_name = binary_name;
- h->binary_argv = binary_argv;
- h->mst = GNUNET_SERVER_mst_create (cb, cb_cls);
- start_helper (h);
+ struct GNUNET_HELPER_Handle *h;
+ unsigned int c;
+
+ h = GNUNET_new(struct GNUNET_HELPER_Handle);
+ h->with_control_pipe = with_control_pipe;
+ /* Lookup in libexec path only if we are starting gnunet helpers */
+ if (NULL != strstr(binary_name, "gnunet"))
+ h->binary_name = GNUNET_OS_get_libexec_binary_path(binary_name);
+ else
+ h->binary_name = GNUNET_strdup(binary_name);
+ for (c = 0; NULL != binary_argv[c]; c++)
+ ;
+ h->binary_argv = GNUNET_malloc(sizeof(char *) * (c + 1));
+ for (c = 0; NULL != binary_argv[c]; c++)
+ h->binary_argv[c] = GNUNET_strdup(binary_argv[c]);
+ h->binary_argv[c] = NULL;
+ h->cb_cls = cb_cls;
+ if (NULL != cb)
+ h->mst = GNUNET_MST_create(cb, h->cb_cls);
+ h->exp_cb = exp_cb;
+ h->retry_back_off = 0;
+ start_helper(h);
return h;
}
/**
- * @brief Kills the helper, closes the pipe and frees the h
+ * Free's the resources occupied by the helper handle
+ *
+ * @param h the helper handle to free
+ */
+void
+GNUNET_HELPER_destroy(struct GNUNET_HELPER_Handle *h)
+{
+ unsigned int c;
+ struct GNUNET_HELPER_SendHandle *sh;
+
+ if (NULL != h->write_task)
+ {
+ GNUNET_SCHEDULER_cancel(h->write_task);
+ h->write_task = NULL;
+ }
+ GNUNET_assert(NULL == h->read_task);
+ GNUNET_assert(NULL == h->restart_task);
+ while (NULL != (sh = h->sh_head))
+ {
+ GNUNET_CONTAINER_DLL_remove(h->sh_head, h->sh_tail, sh);
+ if (NULL != sh->cont)
+ sh->cont(sh->cont_cls, GNUNET_SYSERR);
+ GNUNET_free(sh);
+ }
+ if (NULL != h->mst)
+ GNUNET_MST_destroy(h->mst);
+ GNUNET_free(h->binary_name);
+ for (c = 0; h->binary_argv[c] != NULL; c++)
+ GNUNET_free(h->binary_argv[c]);
+ GNUNET_free(h->binary_argv);
+ GNUNET_free(h);
+}
+
+
+/**
+ * Kills the helper, closes the pipe and frees the handle
*
- * @param h h to helper to stop
+ * @param h handle to helper to stop
+ * @param soft_kill if #GNUNET_YES, signals termination by closing the helper's
+ * stdin; #GNUNET_NO to signal termination by sending SIGTERM to helper
*/
void
-GNUNET_HELPER_stop (struct GNUNET_HELPER_Handle *h)
+GNUNET_HELPER_stop(struct GNUNET_HELPER_Handle *h, int soft_kill)
{
- struct HelperMessageQueueEntry *qe;
-
- /* signal pending writes that we were stopped */
- while (NULL != (qe = h->mq_head))
- {
- GNUNET_CONTAINER_DLL_remove (h->mq_head,
- h->mq_tail,
- qe);
- qe->cont (qe->cont_cls, GNUNET_SYSERR);
- GNUNET_free (qe);
- }
- stop_helper (h);
- GNUNET_SERVER_mst_destroy (h->mst);
- GNUNET_free (h);
+ h->exp_cb = NULL;
+ stop_helper(h, soft_kill);
+ GNUNET_HELPER_destroy(h);
}
* Write to the helper-process
*
* @param cls handle to the helper process
- * @param tc scheduler context
*/
static void
-helper_write (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tsdkctx)
+helper_write(void *cls)
{
struct GNUNET_HELPER_Handle *h = cls;
- struct HelperMessageQueueEntry *qe;
+ struct GNUNET_HELPER_SendHandle *sh;
const char *buf;
ssize_t t;
- h->write_task = GNUNET_SCHEDULER_NO_TASK;
- if (0 != (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
- {
- /* try again */
- h->write_task = GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
- h->fh_to_helper, &helper_write, h);
- return;
- }
- if (NULL == (qe = h->mq_head))
- return; /* how did this happen? */
- buf = (const char*) qe->msg;
- t = GNUNET_DISK_file_write (h->fh_to_helper, &buf[qe->wpos], ntohs (qe->msg->size) - qe->wpos);
- if (t <= 0)
- {
- /* On write-error, restart the helper */
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- _("Error writing to `%s': %s\n"),
- h->binary_name,
- STRERROR (errno));
- stop_helper (h);
- /* Restart the helper */
- h->restart_task =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
- &restart_task, h);
- return;
- }
- qe->wpos += t;
- if (qe->wpos == ntohs (qe->msg->size))
- {
- GNUNET_CONTAINER_DLL_remove (h->mq_head,
- h->mq_tail,
- qe);
- if (NULL != qe->cont)
- qe->cont (qe->cont_cls, GNUNET_YES);
- GNUNET_free (qe);
- }
- if (NULL != h->mq_head)
- h->write_task = GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
- h->fh_to_helper,
- &helper_write,
- h);
+ h->write_task = NULL;
+ if (NULL == (sh = h->sh_head))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Helper write had no work!\n");
+ return; /* how did this happen? */
+ }
+ buf = (const char *)sh->msg;
+ t = GNUNET_DISK_file_write(h->fh_to_helper,
+ &buf[sh->wpos],
+ ntohs(sh->msg->size) - sh->wpos);
+ if (-1 == t)
+ {
+ /* On write-error, restart the helper */
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
+ _("Error writing to `%s': %s\n"),
+ h->binary_name,
+ strerror(errno));
+ if (NULL != h->exp_cb)
+ {
+ h->exp_cb(h->cb_cls);
+ GNUNET_HELPER_stop(h, GNUNET_NO);
+ return;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Stopping and restarting helper task!\n");
+ stop_helper(h, GNUNET_NO);
+ /* Restart the helper */
+ h->restart_task = GNUNET_SCHEDULER_add_delayed(
+ GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ h->retry_back_off),
+ &restart_task,
+ h);
+ return;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitted %u bytes to %s\n",
+ (unsigned int)t,
+ h->binary_name);
+ sh->wpos += t;
+ if (sh->wpos == ntohs(sh->msg->size))
+ {
+ GNUNET_CONTAINER_DLL_remove(h->sh_head, h->sh_tail, sh);
+ if (NULL != sh->cont)
+ sh->cont(sh->cont_cls, GNUNET_YES);
+ GNUNET_free(sh);
+ }
+ if (NULL != h->sh_head)
+ h->write_task =
+ GNUNET_SCHEDULER_add_write_file(GNUNET_TIME_UNIT_FOREVER_REL,
+ h->fh_to_helper,
+ &helper_write,
+ h);
}
* @param h helper to send message to
* @param msg message to send
* @param can_drop can the message be dropped if there is already one in the queue?
- * @param cont continuation to run once the message is out (PREREQ_DONE on succees, CANCEL
- * if the helper process died, NULL during GNUNET_HELPER_stop).
- * @param cont_cls closure for 'cont'
- * @return GNUNET_YES if the message will be sent
- * GNUNET_NO if the message was dropped
+ * @param cont continuation to run once the message is out (#GNUNET_OK on succees, #GNUNET_NO
+ * if the helper process died, #GNUNET_SYSERR during #GNUNET_HELPER_destroy).
+ * @param cont_cls closure for @a cont
+ * @return NULL if the message was dropped,
+ * otherwise handle to cancel *cont* (actual transmission may
+ * not be abortable)
*/
-int
-GNUNET_HELPER_send (struct GNUNET_HELPER_Handle *h,
- const struct GNUNET_MessageHeader *msg,
- int can_drop,
- GNUNET_HELPER_Continuation cont,
- void *cont_cls)
+struct GNUNET_HELPER_SendHandle *
+GNUNET_HELPER_send(struct GNUNET_HELPER_Handle *h,
+ const struct GNUNET_MessageHeader *msg,
+ int can_drop,
+ GNUNET_HELPER_Continuation cont,
+ void *cont_cls)
{
- struct HelperMessageQueueEntry *qe;
+ struct GNUNET_HELPER_SendHandle *sh;
uint16_t mlen;
- if ( (GNUNET_YES == can_drop) &&
- (h->mq_head != NULL) )
- return GNUNET_NO;
- mlen = ntohs (msg->size);
- qe = GNUNET_malloc (sizeof (struct HelperMessageQueueEntry) + mlen);
- qe->msg = (const struct GNUNET_MessageHeader*) &qe[1];
- memcpy (&qe[1], msg, mlen);
- qe->cont = cont;
- qe->cont_cls = cont_cls;
- GNUNET_CONTAINER_DLL_insert_tail (h->mq_head,
- h->mq_tail,
- qe);
- if (GNUNET_SCHEDULER_NO_TASK == h->write_task)
- h->write_task = GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL,
- h->fh_to_helper,
- &helper_write,
- h);
-
- return GNUNET_YES;
+ if (NULL == h->fh_to_helper)
+ return NULL;
+ if ((GNUNET_YES == can_drop) && (NULL != h->sh_head))
+ return NULL;
+ mlen = ntohs(msg->size);
+ sh = GNUNET_malloc(sizeof(struct GNUNET_HELPER_SendHandle) + mlen);
+ sh->msg = (const struct GNUNET_MessageHeader *)&sh[1];
+ GNUNET_memcpy(&sh[1], msg, mlen);
+ sh->h = h;
+ sh->cont = cont;
+ sh->cont_cls = cont_cls;
+ GNUNET_CONTAINER_DLL_insert_tail(h->sh_head, h->sh_tail, sh);
+ if (NULL == h->write_task)
+ h->write_task =
+ GNUNET_SCHEDULER_add_write_file(GNUNET_TIME_UNIT_FOREVER_REL,
+ h->fh_to_helper,
+ &helper_write,
+ h);
+
+ return sh;
+}
+
+/**
+ * Cancel a #GNUNET_HELPER_send operation. If possible, transmitting the
+ * message is also aborted, but at least 'cont' won't be
+ * called.
+ *
+ * @param sh operation to cancel
+ */
+void
+GNUNET_HELPER_send_cancel(struct GNUNET_HELPER_SendHandle *sh)
+{
+ struct GNUNET_HELPER_Handle *h = sh->h;
+
+ sh->cont = NULL;
+ sh->cont_cls = NULL;
+ if (0 == sh->wpos)
+ {
+ GNUNET_CONTAINER_DLL_remove(h->sh_head, h->sh_tail, sh);
+ GNUNET_free(sh);
+ if (NULL == h->sh_head)
+ {
+ GNUNET_SCHEDULER_cancel(h->write_task);
+ h->write_task = NULL;
+ }
+ }
}
projects / oweals / gnunet.git / blobdiff