#include "ecore_private.h"
#include "Ecore.h"

#include <sys/types.h>
#include <signal.h>
#include <unistd.h>

#ifndef WIN32
static Ecore_Exe *exes = NULL;

/**
 * @defgroup Ecore_Exe_Basic_Group Process Spawning Functions
 *
 * Functions that deal with spawned processes.
 */

/**
 * Spawns a child process.
 *
 * This function forks and runs the given command using @c /bin/sh.
 *
 * Note that the process handle is only valid until a child process
 * terminated event is received.  After all handlers for the child process
 * terminated event have been called, the handle will be freed by Ecore.
 * 
 * @param   exe_cmd The command to run with @c /bin/sh.
 * @param   data    Data to attach to the returned process handle.
 * @return  A process handle to the spawned process.
 * @ingroup Ecore_Exe_Basic_Group
 */
Ecore_Exe *
ecore_exe_run(const char *exe_cmd, const void *data)
{
   Ecore_Exe *exe;
   pid_t pid;

   if (!exe_cmd) return NULL;
   pid = fork();   
   if (pid)
     {
	exe = calloc(1, sizeof(Ecore_Exe));
	if (!exe)
	  {
	     kill(pid, SIGKILL);
	     return NULL;
	  }
	ECORE_MAGIC_SET(exe, ECORE_MAGIC_EXE);
	exe->pid = pid;
	exe->data = (void *)data;
	exes = _ecore_list_append(exes, exe);
	return exe;
     }
   setsid();
   execl("/bin/sh", "/bin/sh", "-c", exe_cmd, NULL);
   exit(0);
   return NULL;
}

/**
 * Frees the given process handle.
 *
 * Note that the process that the handle represents is unaffected by this
 * function.
 *
 * @param   exe The given process handle.
 * @return  The data attached to the handle when @ref ecore_exe_run was
 *          called.
 * @ingroup Ecore_Exe_Basic_Group
 */
void *
ecore_exe_free(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_free");
	return NULL;
     }
   return _ecore_exe_free(exe);
}

/**
 * Retrieves the process ID of the given spawned process.
 * @param   exe Handle to the given spawned process.
 * @return  The process ID on success.  @c -1 otherwise.
 * @ingroup Ecore_Exe_Basic_Group
 */
pid_t
ecore_exe_pid_get(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_pid_get");
	return -1;
     }
   return exe->pid;
}

/**
 * Retrieves the data attached to the given process handle.
 * @param   exe The given process handle.
 * @return  The data pointer attached to @p exe.
 * @ingroup Ecore_Exe_Basic_Group
 */
void *
ecore_exe_data_get(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_data_get");
	return NULL;
     }
   return exe->data;
}

/**
 * @defgroup Ecore_Exe_Signal_Group Spawned Process Signal Functions
 *
 * Functions that send signals to spawned processes.
 */

/**
 * Pauses the given process by sending it a @c SIGSTOP signal.
 * @param   exe Process handle to the given process.
 * @ingroup Ecore_Exe_Signal_Group
 */
void
ecore_exe_pause(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_pause");
	return;
     }
   kill(exe->pid, SIGSTOP);
}

/**
 * Continues the given paused process by sending it a @c SIGCONT signal.
 * @param   exe Process handle to the given process.
 * @ingroup Ecore_Exe_Signal_Group
 */
void
ecore_exe_continue(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_continue");
	return;
     }
   kill(exe->pid, SIGCONT);
}

/**
 * Sends the given spawned process a terminate (@c SIGTERM) signal.
 * @param   exe Process handle to the given process.
 * @ingroup Ecore_Exe_Signal_Group
 */
void
ecore_exe_terminate(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_terminate");
	return;
     }
   kill(exe->pid, SIGTERM);
}

/**
 * Kills the given spawned process by sending it a @c SIGKILL signal.
 * @param   exe Process handle to the given process.
 * @ingroup Ecore_Exe_Signal_Group
 */
void
ecore_exe_kill(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_kill");
	return;
     }
   kill(exe->pid, SIGKILL);
}

/**
 * Sends a @c SIGUSR signal to the given spawned process.
 * @param   exe Process handle to the given process.
 * @param   num The number user signal to send.  Must be either 1 or 2, or
 *              the signal will be ignored.
 * @ingroup Ecore_Exe_Signal_Group
 */
void
ecore_exe_signal(Ecore_Exe *exe, int num)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_signal");
	return;
     }
   if (num == 1)
     kill(exe->pid, SIGUSR1);
   else if (num == 2)
     kill(exe->pid, SIGUSR2);
}

/**
 * Sends a @c SIGHUP signal to the given spawned process.
 * @param   exe Process handle to the given process.
 * @ingroup Ecore_Exe_Signal_Group
 */
void
ecore_exe_hup(Ecore_Exe *exe)
{
   if (!ECORE_MAGIC_CHECK(exe, ECORE_MAGIC_EXE))
     {
	ECORE_MAGIC_FAIL(exe, ECORE_MAGIC_EXE,
			 "ecore_exe_hup");
	return;
     }
   kill(exe->pid, SIGHUP);
}

void
_ecore_exe_shutdown(void)
{
   while (exes) _ecore_exe_free(exes);
}

Ecore_Exe *
_ecore_exe_find(pid_t pid)
{
   Ecore_Oldlist *l;
   
   for (l = (Ecore_Oldlist *)exes; l; l = l->next)
     {
	Ecore_Exe *exe;
	
	exe = (Ecore_Exe *)l;
	if (exe->pid == pid) return exe;
     }
   return NULL;
}

void *
_ecore_exe_free(Ecore_Exe *exe)
{
   void *data;
   
   data = exe->data;
   exes = _ecore_list_remove(exes, exe);
   ECORE_MAGIC_SET(exe, ECORE_MAGIC_NONE);
   free(exe);
   return data;
}
#endif