Internal system-dependent API available on UNIX only. More...

Data Structures
struct	DBusUserInfo
	Information about a UNIX user. More...

struct	DBusGroupInfo
	Information about a UNIX group. More...

Typedefs
typedef struct DBusUserInfo	DBusUserInfo
	Information about a UNIX user. More...

typedef struct DBusGroupInfo	DBusGroupInfo
	Information about a UNIX group. More...

typedef void(*	DBusSignalHandler) (int sig)
	A UNIX signal handler. More...

Enumerations
enum	DBusEnsureStandardFdsFlags { DBUS_FORCE_STDIN_NULL = (1 << 0) , DBUS_FORCE_STDOUT_NULL = (1 << 1) , DBUS_FORCE_STDERR_NULL = (1 << 2) }

Functions
DBUS_PRIVATE_EXPORT dbus_bool_t	_dbus_close (int fd, DBusError *error)
	Closes a file descriptor. More...

DBUS_PRIVATE_EXPORT int	_dbus_dup (int fd, DBusError *error)
	Duplicates a file descriptor. More...

DBUS_PRIVATE_EXPORT int	_dbus_read (int fd, DBusString *buffer, int count)
	Thin wrapper around the read() system call that appends the data it reads to the DBusString buffer. More...

int	_dbus_write (int fd, const DBusString *buffer, int start, int len)
	Thin wrapper around the write() system call that writes a part of a DBusString and handles EINTR for you. More...

int	_dbus_write_two (int fd, const DBusString buffer1, int start1, int len1, const DBusString buffer2, int start2, int len2)
	Like _dbus_write() but will use writev() if possible to write both buffers in sequence. More...

int	_dbus_connect_unix_socket (const char path, dbus_bool_t abstract, DBusError error)
	Creates a socket and connects it to the UNIX domain socket at the given path. More...

int	_dbus_listen_unix_socket (const char path, dbus_bool_t abstract, DBusError error)
	Creates a socket and binds it to the given path, then listens on the socket. More...

int	_dbus_connect_exec (const char path, char const argv[], DBusError *error)
	Creates a UNIX domain socket and connects it to the specified process to execute. More...

int	_dbus_listen_systemd_sockets (DBusSocket *fd, DBusError error)
	Acquires one or more sockets passed in from systemd. More...

dbus_bool_t	_dbus_read_credentials (int client_fd, DBusCredentials credentials, DBusError error)

dbus_bool_t	_dbus_send_credentials (int server_fd, DBusError *error)

dbus_bool_t	_dbus_lookup_launchd_socket (DBusString socket_path, const char launchd_env_var, DBusError *error)
	quries launchd for a specific env var which holds the socket path. More...

DBUS_PRIVATE_EXPORT dbus_bool_t	_dbus_lookup_user_bus (dbus_bool_t supported, DBusString address, DBusError *error)

dbus_bool_t	_dbus_user_info_fill (DBusUserInfo info, const DBusString username, DBusError *error)
	Gets user info for the given username. More...

dbus_bool_t	_dbus_user_info_fill_uid (DBusUserInfo info, dbus_uid_t uid, DBusError error)
	Gets user info for the given user ID. More...

void	_dbus_user_info_free (DBusUserInfo *info)
	Frees the members of info (but not info itself) More...

dbus_bool_t	_dbus_group_info_fill (DBusGroupInfo info, const DBusString groupname, DBusError *error)
	Initializes the given DBusGroupInfo struct with information about the given group name. More...

dbus_bool_t	_dbus_group_info_fill_gid (DBusGroupInfo info, dbus_gid_t gid, DBusError error)
	Initializes the given DBusGroupInfo struct with information about the given group ID. More...

void	_dbus_group_info_free (DBusGroupInfo *info)
	Frees the members of info (but not info itself). More...

DBUS_PRIVATE_EXPORT dbus_uid_t	_dbus_geteuid (void)
	Gets our effective UID. More...

DBUS_PRIVATE_EXPORT void	_dbus_close_all (void)
	Closes all file descriptors except the first three (i.e. More...

DBUS_PRIVATE_EXPORT void	_dbus_fd_set_all_close_on_exec (void)
	Sets all file descriptors except the first three (i.e. More...

DBUS_PRIVATE_EXPORT void	_dbus_fd_clear_close_on_exec (int fd)
	Sets the file descriptor to not be close-on-exec. More...

dbus_bool_t	_dbus_append_address_from_socket (DBusSocket fd, DBusString address, DBusError error)
	Read the address from the socket and append it to the string. More...

DBUS_PRIVATE_EXPORT void	_dbus_fd_set_close_on_exec (int fd)
	Sets the file descriptor to be close on exec. More...

DBUS_PRIVATE_EXPORT dbus_bool_t	_dbus_ensure_standard_fds (DBusEnsureStandardFdsFlags flags, const char **error_str_p)
	Ensure that the standard file descriptors stdin, stdout and stderr are open, by opening /dev/null if necessary. More...

void	_dbus_set_signal_handler (int sig, DBusSignalHandler handler)
	Installs a UNIX signal handler. More...

dbus_bool_t	_dbus_reset_oom_score_adj (const char **error_str_p)
	If the current process has been protected from the Linux OOM killer (the oom_score_adj process parameter is negative), reset it to the default level of protection from the OOM killer (set oom_score_adj to zero). More...

Detailed Description

Internal system-dependent API available on UNIX only.

Typedef Documentation

◆ DBusGroupInfo

typedef struct DBusGroupInfo DBusGroupInfo

Information about a UNIX group.

Definition at line 101 of file dbus-sysdeps-unix.h.

◆ DBusSignalHandler

typedef void(* DBusSignalHandler) (int sig)

A UNIX signal handler.

Definition at line 172 of file dbus-sysdeps-unix.h.

◆ DBusUserInfo

typedef struct DBusUserInfo DBusUserInfo

Information about a UNIX user.

Definition at line 99 of file dbus-sysdeps-unix.h.

Enumeration Type Documentation

◆ DBusEnsureStandardFdsFlags

enum DBusEnsureStandardFdsFlags

Definition at line 160 of file dbus-sysdeps-unix.h.

Function Documentation

◆ _dbus_append_address_from_socket()

dbus_bool_t _dbus_append_address_from_socket	(	DBusSocket	fd,
		DBusString *	address,
		DBusError *	error
	)

Read the address from the socket and append it to the string.

Parameters

fd	the socket
address
error	return location for error code

Definition at line 4870 of file dbus-sysdeps-unix.c.

References _dbus_address_append_escaped(), _dbus_string_append(), _dbus_string_init_const(), FALSE, NULL, and TRUE.

Referenced by _dbus_server_listen_platform_specific().

◆ _dbus_close()

DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_close	(	int	fd,
		DBusError *	error
	)

Closes a file descriptor.

Parameters

fd	the file descriptor
error	error object

Returns: FALSE if error set

Definition at line 3561 of file dbus-sysdeps-unix.c.

References _dbus_error_from_errno(), dbus_set_error(), FALSE, and TRUE.

Referenced by _dbus_close_socket(), _dbus_command_for_pid(), _dbus_create_file_exclusively(), _dbus_file_get_contents(), _dbus_generate_random_bytes(), _dbus_listen_systemd_sockets(), _dbus_listen_tcp_socket(), _dbus_message_iter_get_args_valist(), _dbus_reset_oom_score_adj(), _dbus_socketpair(), and _dbus_string_save_to_file().

◆ _dbus_close_all()

DBUS_PRIVATE_EXPORT void _dbus_close_all ( void )

Closes all file descriptors except the first three (i.e.

stdin, stdout, stderr).

Definition at line 4792 of file dbus-sysdeps-unix.c.

Referenced by _dbus_connect_exec().

◆ _dbus_connect_exec()

int _dbus_connect_exec	(	const char *	path,
		char *const	argv[],
		DBusError *	error
	)

Creates a UNIX domain socket and connects it to the specified process to execute.

This will set FD_CLOEXEC for the socket returned.

Parameters

path	the path to the executable
argv	the argument list for the process to execute. argv[0] typically is identical to the path of the executable
error	return location for error code

Returns: connection file descriptor or -1 on error

Definition at line 1033 of file dbus-sysdeps-unix.c.

References _dbus_close_all(), _dbus_error_from_errno(), _dbus_fd_set_close_on_exec(), and dbus_set_error().

◆ _dbus_connect_unix_socket()

int _dbus_connect_unix_socket	(	const char *	path,
		dbus_bool_t	abstract,
		DBusError *	error
	)

Creates a socket and connects it to the UNIX domain socket at the given path.

The connection fd is returned, and is set up as nonblocking.

Uses abstract sockets instead of filesystem-linked sockets if requested (it's possible only on Linux; see "man 7 unix" on Linux). On non-Linux abstract socket usage always fails.

This will set FD_CLOEXEC for the socket returned.

Parameters

path	the path to UNIX domain socket
abstract	TRUE to use abstract namespace
error	return location for error code

Returns: connection file descriptor or -1 on error

Definition at line 936 of file dbus-sysdeps-unix.c.

◆ _dbus_dup()

DBUS_PRIVATE_EXPORT int _dbus_dup	(	int	fd,
		DBusError *	error
	)

Duplicates a file descriptor.

Makes sure the fd returned is >= 3 (i.e. avoids stdin/stdout/stderr). Sets O_CLOEXEC.

Parameters

fd	the file descriptor to duplicate
error	address of error location.

Returns: duplicated file descriptor

Definition at line 3589 of file dbus-sysdeps-unix.c.

References _dbus_error_from_errno(), _dbus_fd_set_close_on_exec(), and dbus_set_error().

Referenced by _dbus_message_iter_get_args_valist(), dbus_message_copy(), and dbus_message_iter_get_basic().

◆ _dbus_ensure_standard_fds()

DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_ensure_standard_fds	(	DBusEnsureStandardFdsFlags	flags,
		const char **	error_str_p
	)

Ensure that the standard file descriptors stdin, stdout and stderr are open, by opening /dev/null if necessary.

This function does not use DBusError, to avoid calling malloc(), so that it can be used in contexts where an async-signal-safe function is required (for example after fork()). Instead, on failure it sets errno and returns something like "Failed to open /dev/null" in *error_str_p. Callers are expected to combine *error_str_p with _dbus_strerror (errno) to get a full error report.

This function can only be called while single-threaded: either during startup of an executable, or after fork().

Definition at line 155 of file dbus-sysdeps-unix.c.

◆ _dbus_fd_clear_close_on_exec()

DBUS_PRIVATE_EXPORT void _dbus_fd_clear_close_on_exec ( int fd )

Sets the file descriptor to not be close-on-exec.

This can be called after _dbus_fd_set_all_close_on_exec() to make exceptions for pipes used to communicate with child processes.

Parameters

fd	the file descriptor

Definition at line 3539 of file dbus-sysdeps-unix.c.

◆ _dbus_fd_set_all_close_on_exec()

DBUS_PRIVATE_EXPORT void _dbus_fd_set_all_close_on_exec ( void )

Sets all file descriptors except the first three (i.e.

stdin, stdout, stderr) to be close-on-execute.

Definition at line 4802 of file dbus-sysdeps-unix.c.

References _dbus_fd_set_close_on_exec().

◆ _dbus_fd_set_close_on_exec()

DBUS_PRIVATE_EXPORT void _dbus_fd_set_close_on_exec ( int fd )

Sets the file descriptor to be close on exec.

Should be called for all file descriptors in D-Bus code.

Parameters

fd	the file descriptor

Definition at line 3517 of file dbus-sysdeps-unix.c.

Referenced by _dbus_accept(), _dbus_connect_exec(), _dbus_dup(), _dbus_fd_set_all_close_on_exec(), _dbus_reset_oom_score_adj(), _dbus_server_new_for_launchd(), and _dbus_socketpair().

◆ _dbus_geteuid()

DBUS_PRIVATE_EXPORT dbus_uid_t _dbus_geteuid ( void )

Gets our effective UID.

Returns: process effective UID

Definition at line 2996 of file dbus-sysdeps-unix.c.

Referenced by _dbus_append_user_from_current_process(), _dbus_homedir_from_uid(), and _dbus_unix_user_is_process_owner().

◆ _dbus_group_info_fill()

dbus_bool_t _dbus_group_info_fill	(	DBusGroupInfo *	info,
		const DBusString *	groupname,
		DBusError *	error
	)

Initializes the given DBusGroupInfo struct with information about the given group name.

Parameters

info	the group info struct
groupname	name of group
error	the error return

Returns: FALSE if error is set

Definition at line 930 of file dbus-sysdeps-util-unix.c.

Referenced by _dbus_user_database_lookup_group().

◆ _dbus_group_info_fill_gid()

dbus_bool_t _dbus_group_info_fill_gid	(	DBusGroupInfo *	info,
		dbus_gid_t	gid,
		DBusError *	error
	)

Initializes the given DBusGroupInfo struct with information about the given group ID.

Parameters

info	the group info struct
gid	group ID
error	the error return

Returns: FALSE if error is set

Definition at line 949 of file dbus-sysdeps-util-unix.c.

Referenced by _dbus_user_database_lookup_group().

◆ _dbus_group_info_free()

void _dbus_group_info_free ( DBusGroupInfo * info )

Frees the members of info (but not info itself).

Parameters

info	the group info

Definition at line 119 of file dbus-userdb.c.

References dbus_free(), and DBusGroupInfo::groupname.

Referenced by _dbus_group_info_unref().

◆ _dbus_listen_systemd_sockets()

int _dbus_listen_systemd_sockets	(	DBusSocket **	fds,
		DBusError *	error
	)

Acquires one or more sockets passed in from systemd.

The sockets are set to be nonblocking.

This will set FD_CLOEXEC for the sockets returned.

Parameters

fds	the file descriptors
error	return location for errors

Returns: the number of file descriptors

Definition at line 1271 of file dbus-sysdeps-unix.c.

References _dbus_close(), _dbus_error_from_errno(), DBUS_ERROR_BAD_ADDRESS, DBUS_ERROR_NO_MEMORY, DBUS_ERROR_NOT_SUPPORTED, dbus_free(), dbus_new, dbus_set_error(), dbus_set_error_const(), NULL, and TRUE.

Referenced by _dbus_server_listen_platform_specific().

◆ _dbus_listen_unix_socket()

int _dbus_listen_unix_socket	(	const char *	path,
		dbus_bool_t	abstract,
		DBusError *	error
	)

Creates a socket and binds it to the given path, then listens on the socket.

The socket is set to be nonblocking.

Uses abstract sockets instead of filesystem-linked sockets if requested (it's possible only on Linux; see "man 7 unix" on Linux). On non-Linux abstract socket usage always fails.

This will set FD_CLOEXEC for the socket returned

Parameters

path	the socket name
abstract	TRUE to use abstract namespace
error	return location for errors

Returns: the listening file descriptor or -1 on error

Definition at line 1144 of file dbus-sysdeps-unix.c.

Referenced by _dbus_server_new_for_domain_socket().

◆ _dbus_lookup_launchd_socket()

dbus_bool_t _dbus_lookup_launchd_socket	(	DBusString *	socket_path,
		const char *	launchd_env_var,
		DBusError *	error
	)

quries launchd for a specific env var which holds the socket path.

Parameters

socket_path	append the socket path to this DBusString
launchd_env_var	the env var to look up
error	a DBusError to store the error in case of failure

Returns: the value of the env var

Definition at line 4317 of file dbus-sysdeps-unix.c.

References _dbus_assert, _dbus_check_setuid(), _DBUS_N_ELEMENTS, _dbus_string_shorten(), DBUS_ERROR_NOT_SUPPORTED, dbus_set_error(), dbus_set_error_const(), FALSE, NULL, and TRUE.

◆ _dbus_lookup_user_bus()

DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_lookup_user_bus	(	dbus_bool_t *	supported,
		DBusString *	address,
		DBusError *	error
	)

Definition at line 4423 of file dbus-sysdeps-unix.c.

◆ _dbus_read()

DBUS_PRIVATE_EXPORT int _dbus_read	(	int	fd,
		DBusString *	buffer,
		int	count
	)

Thin wrapper around the read() system call that appends the data it reads to the DBusString buffer.

It appends up to the given count, and returns the same value and same errno as read(). The only exception is that _dbus_read() handles EINTR for you. Also, _dbus_read() can return ENOMEM, even though regular UNIX read doesn't.

Unlike _dbus_read_socket(), _dbus_read() is not available on Windows.

Parameters

fd	the file descriptor to read from
buffer	the buffer to append data to
count	the amount of data to read

Returns: the number of bytes read or -1

Definition at line 731 of file dbus-sysdeps-unix.c.

References _dbus_assert, _dbus_string_get_data_len(), _dbus_string_lengthen(), _dbus_string_set_length(), and _dbus_verbose_bytes_of_string().

Referenced by _dbus_command_for_pid(), _dbus_file_get_contents(), _dbus_generate_random_bytes(), and _dbus_read_socket().

◆ _dbus_reset_oom_score_adj()

dbus_bool_t _dbus_reset_oom_score_adj ( const char ** error_str_p )

If the current process has been protected from the Linux OOM killer (the oom_score_adj process parameter is negative), reset it to the default level of protection from the OOM killer (set oom_score_adj to zero).

This function does not use DBusError, to avoid calling malloc(), so that it can be used in contexts where an async-signal-safe function is required (for example after fork()). Instead, on failure it sets errno and returns something like "Failed to open /dev/null" in *error_str_p. Callers are expected to combine *error_str_p with _dbus_strerror (errno) to get a full error report.

Definition at line 1620 of file dbus-sysdeps-util-unix.c.

References _dbus_close(), _dbus_fd_set_close_on_exec(), FALSE, NULL, and TRUE.

◆ _dbus_set_signal_handler()

void _dbus_set_signal_handler	(	int	sig,
		DBusSignalHandler	handler
	)

Installs a UNIX signal handler.

Parameters

sig	the signal to handle
handler	the handler

Definition at line 544 of file dbus-sysdeps-util-unix.c.

References NULL.

◆ _dbus_user_info_fill()

dbus_bool_t _dbus_user_info_fill	(	DBusUserInfo *	info,
		const DBusString *	username,
		DBusError *	error
	)

Gets user info for the given username.

Parameters

info	user info object to initialize
username	the username
error	error return

Returns: TRUE on success

Definition at line 2898 of file dbus-sysdeps-unix.c.

References DBUS_UID_UNSET.

Referenced by _dbus_user_database_lookup().

◆ _dbus_user_info_fill_uid()

dbus_bool_t _dbus_user_info_fill_uid	(	DBusUserInfo *	info,
		dbus_uid_t	uid,
		DBusError *	error
	)

Gets user info for the given user ID.

Parameters

info	user info object to initialize
uid	the user ID
error	error return

Returns: TRUE on success

Definition at line 2915 of file dbus-sysdeps-unix.c.

References NULL.

Referenced by _dbus_user_database_lookup().

◆ _dbus_user_info_free()

void _dbus_user_info_free ( DBusUserInfo * info )

Frees the members of info (but not info itself)

Parameters

info	the user info struct

Definition at line 106 of file dbus-userdb.c.

References dbus_free(), DBusUserInfo::group_ids, DBusUserInfo::homedir, and DBusUserInfo::username.

Referenced by _dbus_user_info_unref().

◆ _dbus_write()

int _dbus_write	(	int	fd,
		const DBusString *	buffer,
		int	start,
		int	len
	)

Thin wrapper around the write() system call that writes a part of a DBusString and handles EINTR for you.

Parameters

fd	the file descriptor to write
buffer	the buffer to write data from
start	the first byte in the buffer to write
len	the number of bytes to try to write

Returns: the number of bytes written or -1 on error

Definition at line 791 of file dbus-sysdeps-unix.c.

References _dbus_verbose_bytes_of_string().

Referenced by _dbus_string_save_to_file(), _dbus_write_socket(), and _dbus_write_two().

◆ _dbus_write_two()

int _dbus_write_two	(	int	fd,
		const DBusString *	buffer1,
		int	start1,
		int	len1,
		const DBusString *	buffer2,
		int	start2,
		int	len2
	)

Like _dbus_write() but will use writev() if possible to write both buffers in sequence.

The return value is the number of bytes written in the first buffer, plus the number written in the second. If the first buffer is written successfully and an error occurs writing the second, the number of bytes in the first is returned (i.e. the error is ignored), on systems that don't have writev. Handles EINTR for you. The second buffer may be NULL.

Parameters

fd	the file descriptor
buffer1	first buffer
start1	first byte to write in first buffer
len1	number of bytes to write from first buffer
buffer2	second buffer, or NULL
start2	first byte to write in second buffer
len2	number of bytes to write in second buffer

Returns: total bytes written from both buffers, or -1 on error

Definition at line 837 of file dbus-sysdeps-unix.c.

References _dbus_assert, _dbus_write(), and NULL.

Referenced by _dbus_write_socket_two().

Data Structures

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ DBusGroupInfo

◆ DBusSignalHandler

◆ DBusUserInfo

Enumeration Type Documentation

◆ DBusEnsureStandardFdsFlags

Function Documentation

◆ _dbus_append_address_from_socket()

◆ _dbus_close()

◆ _dbus_close_all()

◆ _dbus_connect_exec()

◆ _dbus_connect_unix_socket()

◆ _dbus_dup()

◆ _dbus_ensure_standard_fds()

◆ _dbus_fd_clear_close_on_exec()

◆ _dbus_fd_set_all_close_on_exec()

◆ _dbus_fd_set_close_on_exec()

◆ _dbus_geteuid()

◆ _dbus_group_info_fill()

◆ _dbus_group_info_fill_gid()

◆ _dbus_group_info_free()

◆ _dbus_listen_systemd_sockets()

◆ _dbus_listen_unix_socket()

◆ _dbus_lookup_launchd_socket()

◆ _dbus_lookup_user_bus()

◆ _dbus_read()

◆ _dbus_reset_oom_score_adj()

◆ _dbus_set_signal_handler()

◆ _dbus_user_info_fill()

◆ _dbus_user_info_fill_uid()

◆ _dbus_user_info_free()

◆ _dbus_write()

◆ _dbus_write_two()