nilix/tint2
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add Linux kernel event handling code

Browse source 
This is a simple handler for uevents send by the Linux
kernel.
This commit is contained in:
Sebastian Reichel 2015-08-08 05:49:21 +02:00
parent 1051be9815
commit 46a6d2c2ad
4 changed files with 293 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
CMakeLists.txt
View file

@ -7,6 +7,9 @@ option( ENABLE_EXAMPLES "Install additional tin2rc examples" ON )
option( ENABLE_RSVG "Rsvg support (launcher only)" ON )
option( ENABLE_SN "Startup notification support" ON )
option( ENABLE_ASAN "Build tint2 with AddressSanitizer" OFF )
if( CMAKE_SYSTEM_NAME STREQUAL "Linux" )
option( ENABLE_UEVENT "Kernel event handling support" ON )
endif( CMAKE_SYSTEM_NAME STREQUAL "Linux" )
include( FindPkgConfig )
include( CheckLibraryExists )
@ -111,6 +114,11 @@ if( ENABLE_SN )
endif( SN_FOUND )
endif( ENABLE_SN)
if( ENABLE_UEVENT )
add_definitions( -DENABLE_UEVENT )
set( SOURCES ${SOURCES} src/util/uevent.c)
endif( ENABLE_UEVENT )
if( ENABLE_TINT2CONF )
add_definitions( -DHAVE_VERSION_H )
add_subdirectory( src/tint2conf )

11
src/tint.c
View file

@ -49,6 +49,7 @@
#include "tooltip.h"
#include "timer.h"
#include "xsettings-client.h"
#include "uevent.h"
// Drag and Drop state variables
Window dnd_source_window;
@ -340,6 +341,8 @@ void cleanup()
}
}
#endif
uevent_cleanup();
}
@ -1201,6 +1204,8 @@ start:
dnd_sent_request = 0;
dnd_launcher_exec = 0;
int ufd = uevent_init();
// sigset_t empty_mask;
// sigemptyset(&empty_mask);
@ -1243,6 +1248,10 @@ start:
FD_SET (sn_pipe[0], &fdset);
maxfd = maxfd < sn_pipe[0] ? sn_pipe[0] : maxfd;
}
if (ufd > 0) {
FD_SET (ufd, &fdset);
maxfd = maxfd < ufd ? ufd : maxfd;
}
update_next_timeout();
if (next_timeout.tv_sec >= 0 && next_timeout.tv_usec >= 0)
select_timeout = &next_timeout;
@ -1251,6 +1260,8 @@ start:
// Wait for X Event or a Timer
if (XPending(server.dsp) > 0 || select(maxfd+1, &fdset, 0, 0, select_timeout) >= 0) {
uevent_handler();
if (sn_pipe_valid) {
char buffer[1];
while (read(sn_pipe[0], buffer, sizeof(buffer)) > 0) {

204
src/util/uevent.c Normal file
View file

@ -0,0 +1,204 @@
/**************************************************************************
*
* Linux Kernel uevent handler
*
* Copyright (C) 2015 Sebastian Reichel <sre@ring0.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
* or any later version as published by the Free Software Foundation.
*
* This program 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.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
**************************************************************************/
#ifdef ENABLE_UEVENT
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <linux/types.h>
#include <linux/netlink.h>
#include "common.h"
#include "uevent.h"
static int ueventfd = -1;
static struct sockaddr_nl nls;
static GList *notifiers = NULL;
static const char* has_prefix(const char *str, const char *end, const char *prefix, size_t prefixlen) {
if ((end-str) < prefixlen)
return NULL;
if (!memcmp(str, prefix, prefixlen))
return str + prefixlen;
return NULL;
}
#define HAS_CONST_PREFIX(str,end,prefix) has_prefix((str),end,prefix,sizeof(prefix)-1)
static void uevent_param_free(gpointer data) {
struct uevent_parameter *param = data;
free(param->key);
free(param->val);
free(param);
}
static void uevent_free(struct uevent *ev) {
free(ev->path);
free(ev->subsystem);
g_list_free_full(ev->params, uevent_param_free);
free(ev);
}
static struct uevent *uevent_new(char *buffer, int size) {
struct uevent *ev;
const char* s = buffer;
const char* end = s + size;
gboolean first = TRUE;
if (size == 0)
return NULL;
ev = calloc(1, sizeof(*ev));
if (!ev)
return NULL;
/* ensure nul termination required by strlen() */
buffer[size-1] = '\0';
for (; s < end; s += strlen(s) + 1) {
if (first) {
const char *p;
for (p = s; *p != '@'; p++) {
if (!*p) {
/* error: kernel events contain @ */
/* triggered by udev events, though */
free(ev);
return NULL;
}
}
ev->path = strdup(p+1);
first = FALSE;
} else {
const char* val;
if ((val = HAS_CONST_PREFIX(s, end, "ACTION=")) != NULL) {
if (!strcmp(val, "add"))
ev->action = UEVENT_ADD;
else if (!strcmp(val, "remove"))
ev->action = UEVENT_REMOVE;
else if (!strcmp(val, "change"))
ev->action = UEVENT_CHANGE;
else
ev->action = UEVENT_UNKNOWN;
} else if ((val = HAS_CONST_PREFIX(s, end, "SEQNUM=")) != NULL) {
ev->sequence = atoi(val);
} else if ((val = HAS_CONST_PREFIX(s, end, "SUBSYSTEM=")) != NULL) {
ev->subsystem = strdup(val);
} else {
val = strchr(s, '=');
if (val) {
struct uevent_parameter *param = malloc(sizeof(*param));
if(param) {
param->key = strndup(s, val-s);
param->val = strdup(val+1);
ev->params = g_list_append(ev->params, param);
}
}
}
}
}
return ev;
}
void uevent_register_notifier(struct uevent_notify *nb) {
notifiers = g_list_append(notifiers, nb);
}
void uevent_unregister_notifier(struct uevent_notify *nb) {
GList *l = notifiers;
while (l != NULL) {
GList *next = l->next;
struct uevent_notify *lnb = l->data;
if(memcmp(nb, lnb, sizeof(struct uevent_notify)) == 0)
notifiers = g_list_delete_link(notifiers, l);
l = next;
}
}
void uevent_handler() {
struct uevent *ev;
char buf[512];
GList *l;
if (ueventfd < 0)
return;
int len = recv(ueventfd, buf, sizeof(buf), MSG_DONTWAIT);
if (len < 0)
return;
ev = uevent_new(buf, len);
if(ev) {
for (l = notifiers; l != NULL; l = l->next) {
struct uevent_notify *nb = l->data;
if (!(ev->action & nb->action))
continue;
if (nb->subsystem && strcmp(ev->subsystem, nb->subsystem))
continue;
nb->cb(ev, nb->userdata);
}
uevent_free(ev);
}
}
int uevent_init() {
/* Open hotplug event netlink socket */
memset(&nls,0,sizeof(struct sockaddr_nl));
nls.nl_family = AF_NETLINK;
nls.nl_pid = getpid();
nls.nl_groups = -1;
/* open socket */
ueventfd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
if (ueventfd < 0) {
fprintf(stderr, "Error: socket open failed\n");
return -1;
}
/* Listen to netlink socket */
if (bind(ueventfd, (void *)&nls, sizeof(struct sockaddr_nl))) {
fprintf(stderr, "Bind failed\n");
return -1;
}
printf("Kernel uevent interface initialized...\n");
return ueventfd;
}
void uevent_cleanup() {
if (ueventfd >= 0)
close(ueventfd);
}
#endif

70
src/util/uevent.h Normal file
View file

@ -0,0 +1,70 @@
/**************************************************************************
*
* Linux Kernel uevent handler
*
* Copyright (C) 2015 Sebastian Reichel <sre@ring0.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
* or any later version as published by the Free Software Foundation.
*
* This program 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.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
**************************************************************************/
#ifndef UEVENT_H
#define UEVENT_H
enum uevent_action {
UEVENT_UNKNOWN = 0x01,
UEVENT_ADD = 0x02,
UEVENT_REMOVE = 0x04,
UEVENT_CHANGE = 0x08,
};
struct uevent_parameter {
char *key;
char *val;
};
struct uevent {
char *path;
enum uevent_action action;
int sequence;
char *subsystem;
GList *params;
};
struct uevent_notify {
int action; /* bitfield */
char *subsystem; /* NULL => any */
void *userdata;
void (*cb)(struct uevent *e, void *userdata);
};
#if ENABLE_UEVENT
int uevent_init();
void uevent_cleanup();
void uevent_handler();
void uevent_register_notifier(struct uevent_notify *nb);
void uevent_unregister_notifier(struct uevent_notify *nb);
#else
static inline int uevent_init() {
return -1;
}
static inline void uevent_cleanup() { }
static inline void uevent_handler() { }
static inline void uevent_register_notifier(struct uevent_notify *nb) { }
static inline void uevent_unregister_notifier(struct uevent_notify *nb) { }
#endif
#endif