GNUnet  0.11.x
Data Structures | Functions | Variables
child_management.c File Reference
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_child_management_lib.h"
Include dependency graph for child_management.c:

Go to the source code of this file.

Data Structures

struct  GNUNET_ChildWaitHandle
 Struct which defines a Child Wait handle. More...
 

Functions

static void maint_child_death (void *cls)
 Task triggered whenever we receive a SIGCHLD (child process died) or when user presses CTRL-C. More...
 
static void sighandler_child_death (void)
 Signal handler called for SIGCHLD. More...
 
void __attribute__ ((constructor))
 
struct GNUNET_ChildWaitHandleGNUNET_wait_child (struct GNUNET_OS_Process *proc, GNUNET_ChildCompletedCallback cb, void *cb_cls)
 Starts the handling of the child processes. More...
 
void GNUNET_wait_child_cancel (struct GNUNET_ChildWaitHandle *cwh)
 Stop waiting on this child. More...
 
void __attribute__ ((destructor))
 Clean up. More...
 

Variables

static struct GNUNET_DISK_PipeHandlesigpipe
 Pipe used to communicate shutdown via signal. More...
 
static struct GNUNET_SIGNAL_Contextshc_chld
 
static struct GNUNET_SCHEDULER_Tasksig_task
 
static struct GNUNET_ChildWaitHandlecwh_head
 
static struct GNUNET_ChildWaitHandlecwh_tail
 

Function Documentation

◆ maint_child_death()

static void maint_child_death ( void *  cls)
static

Task triggered whenever we receive a SIGCHLD (child process died) or when user presses CTRL-C.

Parameters
clsclosure, NULL

Definition at line 81 of file child_management.c.

References buf, exit_code, GNUNET_assert, GNUNET_CONTAINER_DLL_remove, GNUNET_DISK_file_read(), GNUNET_DISK_handle_invalid(), GNUNET_DISK_PIPE_END_READ, GNUNET_DISK_pipe_handle(), GNUNET_free, GNUNET_OK, GNUNET_OS_process_status(), GNUNET_SCHEDULER_add_read_file(), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_ChildWaitHandle::next, and type.

Referenced by GNUNET_wait_child().

82 {
83  char buf[16];
84  const struct GNUNET_DISK_FileHandle *pr;
85  struct GNUNET_ChildWaitHandle *nxt;
86 
87  (void) cls;
88  sig_task = NULL;
89  /* drain pipe */
93 
94  (void) GNUNET_DISK_file_read (pr,
95  buf,
96  sizeof(buf));
97 
98  /* find applicable processes that exited */
99  for (struct GNUNET_ChildWaitHandle *cwh = cwh_head;
100  NULL != cwh;
101  cwh = nxt)
102  {
104  long unsigned int exit_code = 0;
105 
106  nxt = cwh->next;
107  if (GNUNET_OK ==
108  GNUNET_OS_process_status (cwh->proc,
109  &type,
110  &exit_code))
111  {
113  cwh_tail,
114  cwh);
115  cwh->cb (cwh->cb_cls,
116  type,
117  exit_code);
118  GNUNET_free (cwh);
119  }
120  }
121  if (NULL == cwh_head)
122  return;
123  /* wait for more */
129  NULL);
130 }
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
static struct GNUNET_DISK_PipeHandle * sigpipe
Pipe used to communicate shutdown via signal.
ssize_t GNUNET_DISK_file_read(const struct GNUNET_DISK_FileHandle *h, void *result, size_t len)
Read the contents of a binary file into a buffer.
Definition: disk.c:602
int GNUNET_OS_process_status(struct GNUNET_OS_Process *proc, enum GNUNET_OS_ProcessStatusType *type, unsigned long *code)
Retrieve the status of a process.
Definition: os_priority.c:946
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_read_file(struct GNUNET_TIME_Relative delay, const struct GNUNET_DISK_FileHandle *rfd, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay or when the specified file descriptor is ready f...
Definition: scheduler.c:1667
const struct GNUNET_DISK_FileHandle * GNUNET_DISK_pipe_handle(const struct GNUNET_DISK_PipeHandle *p, enum GNUNET_DISK_PipeEnd n)
Get the handle to a particular pipe end.
Definition: disk.c:1436
GNUNET_OS_ProcessStatusType
Process status types.
static char buf[2048]
#define GNUNET_TIME_UNIT_FOREVER_REL
Constant used to specify "forever".
The reading-end of a pipe.
static void maint_child_death(void *cls)
Task triggered whenever we receive a SIGCHLD (child process died) or when user presses CTRL-C...
struct GNUNET_ChildWaitHandle * next
Linked list to the next child.
static struct GNUNET_ChildWaitHandle * cwh_tail
enum GNUNET_GenericReturnValue GNUNET_DISK_handle_invalid(const struct GNUNET_DISK_FileHandle *h)
Checks whether a handle is invalid.
Definition: disk.c:186
static struct GNUNET_ChildWaitHandle * cwh_head
static struct GNUNET_SCHEDULER_Task * sig_task
Struct which defines a Child Wait handle.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
Handle used to access files (and pipes).
#define GNUNET_free(ptr)
Wrapper around free.
static long unsigned int exit_code
Handler exit code.
Definition: gnunet-qr.c:54
Here is the call graph for this function:
Here is the caller graph for this function:

◆ sighandler_child_death()

static void sighandler_child_death ( void  )
static

Signal handler called for SIGCHLD.

Triggers the respective handler by writing to the trigger pipe.

Definition at line 138 of file child_management.c.

References GNUNET_break, GNUNET_DISK_file_write(), GNUNET_DISK_PIPE_END_WRITE, and GNUNET_DISK_pipe_handle().

Referenced by __attribute__().

139 {
140  static char c;
141  int old_errno = errno; /* back-up errno */
142 
143  GNUNET_break (
144  1 ==
147  &c,
148  sizeof(c)));
149  errno = old_errno; /* restore errno */
150 }
static struct GNUNET_DISK_PipeHandle * sigpipe
Pipe used to communicate shutdown via signal.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
const struct GNUNET_DISK_FileHandle * GNUNET_DISK_pipe_handle(const struct GNUNET_DISK_PipeHandle *p, enum GNUNET_DISK_PipeEnd n)
Get the handle to a particular pipe end.
Definition: disk.c:1436
ssize_t GNUNET_DISK_file_write(const struct GNUNET_DISK_FileHandle *h, const void *buffer, size_t n)
Write a buffer to a file.
Definition: disk.c:666
The writing-end of a pipe.
Here is the call graph for this function:
Here is the caller graph for this function:

◆ __attribute__() [1/2]

void __attribute__ ( (constructor)  )

Definition at line 153 of file child_management.c.

References GNUNET_assert, GNUNET_DISK_PF_NONE, GNUNET_DISK_pipe(), GNUNET_SIGCHLD, GNUNET_SIGNAL_handler_install(), and sighandler_child_death().

155 {
156  if (NULL != sigpipe)
157  return; /* already initialized */
159  GNUNET_assert (sigpipe != NULL);
160  shc_chld =
162 }
static struct GNUNET_SIGNAL_Context * shc_chld
No special options, use non-blocking read/write operations.
static struct GNUNET_DISK_PipeHandle * sigpipe
Pipe used to communicate shutdown via signal.
#define GNUNET_SIGCHLD
Definition: platform.h:42
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
static void sighandler_child_death(void)
Signal handler called for SIGCHLD.
struct GNUNET_DISK_PipeHandle * GNUNET_DISK_pipe(enum GNUNET_DISK_PipeFlags pf)
Creates an interprocess channel.
Definition: disk.c:1262
struct GNUNET_SIGNAL_Context * GNUNET_SIGNAL_handler_install(int signal, GNUNET_SIGNAL_Handler handler)
Install a signal handler that will be run if the given signal is received.
Definition: signal.c:51
Here is the call graph for this function:

◆ GNUNET_wait_child()

struct GNUNET_ChildWaitHandle* GNUNET_wait_child ( struct GNUNET_OS_Process proc,
GNUNET_ChildCompletedCallback  cb,
void *  cb_cls 
)

Starts the handling of the child processes.

Function checks the status of the child process and sends back a GNUNET_ChildCompletedCallback upon completion/death of the child.

Parameters
procchild process which is monitored
cbreference to the callback which is called after completion
cb_clsclosure for the callback
Returns
GNUNET_ChildWaitHandle is returned

Definition at line 166 of file child_management.c.

References GNUNET_ChildWaitHandle::cb, GNUNET_ChildWaitHandle::cb_cls, GNUNET_CONTAINER_DLL_insert, GNUNET_DISK_PIPE_END_READ, GNUNET_DISK_pipe_handle(), GNUNET_new, GNUNET_SCHEDULER_add_read_file(), GNUNET_TIME_UNIT_FOREVER_REL, maint_child_death(), and GNUNET_ChildWaitHandle::proc.

169 {
170  struct GNUNET_ChildWaitHandle *cwh;
171 
172  child_management_start ();
173  cwh = GNUNET_new (struct GNUNET_ChildWaitHandle);
174  cwh->proc = proc;
175  cwh->cb = cb;
176  cwh->cb_cls = cb_cls;
178  cwh_tail,
179  cwh);
180  if (NULL == sig_task)
181  {
187  NULL);
188  }
189  return cwh;
190 }
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
static struct GNUNET_DISK_PipeHandle * sigpipe
Pipe used to communicate shutdown via signal.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_read_file(struct GNUNET_TIME_Relative delay, const struct GNUNET_DISK_FileHandle *rfd, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay or when the specified file descriptor is ready f...
Definition: scheduler.c:1667
#define GNUNET_new(type)
Allocate a struct or union of the given type.
const struct GNUNET_DISK_FileHandle * GNUNET_DISK_pipe_handle(const struct GNUNET_DISK_PipeHandle *p, enum GNUNET_DISK_PipeEnd n)
Get the handle to a particular pipe end.
Definition: disk.c:1436
struct GNUNET_OS_Process * proc
Child process which is managed.
void * cb_cls
Closure for the handle.
#define GNUNET_TIME_UNIT_FOREVER_REL
Constant used to specify "forever".
The reading-end of a pipe.
static void maint_child_death(void *cls)
Task triggered whenever we receive a SIGCHLD (child process died) or when user presses CTRL-C...
GNUNET_ChildCompletedCallback cb
Callback which is called upon completion/death of the child task.
static struct GNUNET_ChildWaitHandle * cwh_tail
static struct GNUNET_ChildWaitHandle * cwh_head
static struct GNUNET_SCHEDULER_Task * sig_task
Struct which defines a Child Wait handle.
Here is the call graph for this function:

◆ GNUNET_wait_child_cancel()

void GNUNET_wait_child_cancel ( struct GNUNET_ChildWaitHandle cwh)

Stop waiting on this child.

Definition at line 194 of file child_management.c.

References GNUNET_CONTAINER_DLL_remove, GNUNET_free, and GNUNET_SCHEDULER_cancel().

195 {
197  cwh_tail,
198  cwh);
199  if (NULL == cwh_head)
200  {
202  sig_task = NULL;
203  }
204  GNUNET_free (cwh);
205 }
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
static struct GNUNET_ChildWaitHandle * cwh_tail
static struct GNUNET_ChildWaitHandle * cwh_head
static struct GNUNET_SCHEDULER_Task * sig_task
#define GNUNET_free(ptr)
Wrapper around free.
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:972
Here is the call graph for this function:

◆ __attribute__() [2/2]

void __attribute__ ( (destructor)  )

Clean up.

Definition at line 211 of file child_management.c.

References GNUNET_assert, GNUNET_DISK_pipe_close(), and GNUNET_SIGNAL_handler_uninstall().

213 {
214  GNUNET_assert (NULL == sig_task);
216  shc_chld = NULL;
218  sigpipe = NULL;
219 }
static struct GNUNET_SIGNAL_Context * shc_chld
static struct GNUNET_DISK_PipeHandle * sigpipe
Pipe used to communicate shutdown via signal.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
void GNUNET_SIGNAL_handler_uninstall(struct GNUNET_SIGNAL_Context *ctx)
Uninstall a previously installed signal handler.
Definition: signal.c:77
enum GNUNET_GenericReturnValue GNUNET_DISK_pipe_close(struct GNUNET_DISK_PipeHandle *p)
Closes an interprocess channel.
Definition: disk.c:1405
static struct GNUNET_SCHEDULER_Task * sig_task
Here is the call graph for this function:

Variable Documentation

◆ sigpipe

struct GNUNET_DISK_PipeHandle* sigpipe
static

Pipe used to communicate shutdown via signal.

Definition at line 64 of file child_management.c.

◆ shc_chld

struct GNUNET_SIGNAL_Context* shc_chld
static

Definition at line 66 of file child_management.c.

Referenced by main().

◆ sig_task

struct GNUNET_SCHEDULER_Task* sig_task
static

Definition at line 68 of file child_management.c.

◆ cwh_head

struct GNUNET_ChildWaitHandle* cwh_head
static

Definition at line 70 of file child_management.c.

◆ cwh_tail

struct GNUNET_ChildWaitHandle* cwh_tail
static

Definition at line 72 of file child_management.c.