* @author Ioana Patrascu
* @author Tzvetan Horozov
* @author Milan
+ *
+ * This code manages child processes. We can communicate with child
+ * processes using signals. Because signals are not supported on W32
+ * and Java (at least not nicely), we can alternatively use a pipe
+ * to send signals to the child processes (if the child process is
+ * a full-blown GNUnet process that supports reading signals from
+ * a pipe, of course). Naturally, this also only works for 'normal'
+ * termination via signals, and not as a replacement for SIGKILL.
+ * Thus using pipes to communicate signals should only be enabled if
+ * the child is a Java process OR if we are on Windoze.
*/
#ifndef GNUNET_OS_LIB_H
#include "gnunet_configuration_lib.h"
#include "gnunet_scheduler_lib.h"
+
+/**
+ * Flags that determine which of the standard streams
+ * should be inherited by the child process.
+ */
+enum GNUNET_OS_InheritStdioFlags
+{
+
+ /**
+ * No standard streams should be inherited.
+ */
+ GNUNET_OS_INHERIT_STD_NONE = 0,
+
+ /**
+ * When this flag is set, the child process will
+ * inherit stdin of the parent.
+ */
+ GNUNET_OS_INHERIT_STD_IN = 1,
+
+ /**
+ * When this flag is set, the child process will
+ * inherit stdout of the parent.
+ */
+ GNUNET_OS_INHERIT_STD_OUT = 2,
+
+ /**
+ * When this flag is set, the child process will
+ * inherit stderr of the parent.
+ */
+ GNUNET_OS_INHERIT_STD_ERR = 4,
+
+ /**
+ * When these flags are set, the child process will
+ * inherit stdout and stderr of the parent.
+ */
+ GNUNET_OS_INHERIT_STD_OUT_AND_ERR = 6,
+
+ /**
+ * Use this option to have all of the standard streams
+ * (stdin, stdout and stderror) be inherited.
+ */
+ GNUNET_OS_INHERIT_STD_ALL = 7
+};
+
+
/**
* Process information (OS-dependent)
*/
/**
- * Sends sig to the process
+ * Sends a signal to the process
*
* @param proc pointer to process structure
* @param sig signal
* @param proc pointer to process structure
*/
void
-GNUNET_OS_process_close (struct GNUNET_OS_Process *proc);
+GNUNET_OS_process_destroy (struct GNUNET_OS_Process *proc);
+
/**
* Get the pid of the process in question
pid_t
GNUNET_OS_process_get_pid (struct GNUNET_OS_Process *proc);
+
/**
* Set process priority
*
/**
* Start a process.
*
+ * @param pipe_control should a pipe be used to send signals to the child?
+ * @param std_inheritance a set of GNUNET_OS_INHERIT_STD_* flags
+ * @param pipe_stdin pipe to use to send input to child process (or NULL)
+ * @param pipe_stdout pipe to use to get output from child process (or NULL)
+ * @param filename name of the binary
+ * @param argv NULL-terminated array of arguments to the process
+ * @return pointer to process structure of the new process, NULL on error
+ */
+struct GNUNET_OS_Process *
+GNUNET_OS_start_process_vap (int pipe_control,
+ enum GNUNET_OS_InheritStdioFlags std_inheritance,
+ struct GNUNET_DISK_PipeHandle *pipe_stdin,
+ struct GNUNET_DISK_PipeHandle *pipe_stdout,
+ const char *filename,
+ char *const argv[]);
+
+
+/**
+ * Start a process.
+ *
+ * @param pipe_control should a pipe be used to send signals to the child?
+ * @param std_inheritance a set of GNUNET_OS_INHERIT_STD_* flags
* @param pipe_stdin pipe to use to send input to child process (or NULL)
* @param pipe_stdout pipe to use to get output from child process (or NULL)
* @param filename name of the binary
* @return pointer to process structure of the new process, NULL on error
*/
struct GNUNET_OS_Process *
-GNUNET_OS_start_process (struct GNUNET_DISK_PipeHandle *pipe_stdin,
+GNUNET_OS_start_process (int pipe_control,
+ enum GNUNET_OS_InheritStdioFlags std_inheritance,
+ struct GNUNET_DISK_PipeHandle *pipe_stdin,
struct GNUNET_DISK_PipeHandle *pipe_stdout,
const char *filename, ...);
/**
* Start a process.
*
+ * @param pipe_control should a pipe be used to send signals to the child?
+ * @param std_inheritance a set of GNUNET_OS_INHERIT_STD_* flags
* @param pipe_stdin pipe to use to send input to child process (or NULL)
* @param pipe_stdout pipe to use to get output from child process (or NULL)
* @param filename name of the binary
* @return pointer to process structure of the new process, NULL on error
*/
struct GNUNET_OS_Process *
-GNUNET_OS_start_process_va (struct GNUNET_DISK_PipeHandle *pipe_stdin,
+GNUNET_OS_start_process_va (int pipe_control,
+ enum GNUNET_OS_InheritStdioFlags std_inheritance,
+ struct GNUNET_DISK_PipeHandle *pipe_stdin,
struct GNUNET_DISK_PipeHandle *pipe_stdout,
const char *filename, va_list va);
/**
* Start a process.
*
+ * @param pipe_control should a pipe be used to send signals to the child?
+ * @param std_inheritance a set of GNUNET_OS_INHERIT_STD_* flags
* @param lsocks array of listen sockets to dup systemd-style (or NULL);
* must be NULL on platforms where dup is not supported
* @param filename name of the binary
* @return pointer to process structure of the new process, NULL on error
*/
struct GNUNET_OS_Process *
-GNUNET_OS_start_process_v (const SOCKTYPE *lsocks, const char *filename,
+GNUNET_OS_start_process_v (int pipe_control,
+ enum GNUNET_OS_InheritStdioFlags std_inheritance,
+ const SOCKTYPE *lsocks,
+ const char *filename,
char *const argv[]);
*/
struct GNUNET_OS_CommandHandle;
+
/**
* Type of a function to process a line of output.
*
*/
typedef void (*GNUNET_OS_LineProcessor) (void *cls, const char *line);
+
/**
* Stop/kill a command.
*
/**
- * Retrieve the status of a process. Nonblocking version.
+ * Retrieve the status of a process, waiting on him if dead.
+ * Nonblocking version.
*
* @param proc pointer to process structure
* @param type status type
/**
- * Connects this process to its parent via pipe
+ * Connects this process to its parent via pipe;
+ * essentially, the parent control handler will read signal numbers
+ * from the 'GNUNET_OS_CONTROL_PIPE' (as given in an environment
+ * variable) and raise those signals.
+ *
+ * @param cls closure (unused)
+ * @param tc scheduler context (unused)
*/
void
GNUNET_OS_install_parent_control_handler (void *cls,