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Merge "Clean up the locking in usb_linux.cpp."

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This commit is contained in:
Elliott Hughes 2015-07-24 20:21:53 +00:00 • committed by Gerrit Code Review
commit 9dad4ec440
2 changed files with 182 additions and 247 deletions
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1
adb/Android.mk
View file

@ -47,6 +47,7 @@ LIBADB_TEST_SRCS := \
LIBADB_CFLAGS := \ LIBADB_CFLAGS := \
$(ADB_COMMON_CFLAGS) \ $(ADB_COMMON_CFLAGS) \
-fvisibility=hidden \ -fvisibility=hidden \
-std=c++14 \
LIBADB_darwin_SRC_FILES := \ LIBADB_darwin_SRC_FILES := \
fdevent.cpp \ fdevent.cpp \

428
adb/usb_linux.cpp
View file

@ -22,6 +22,7 @@
#include <dirent.h> #include <dirent.h>
#include <errno.h> #include <errno.h>
#include <fcntl.h> #include <fcntl.h>
#include <linux/usb/ch9.h>
#include <linux/usbdevice_fs.h> #include <linux/usbdevice_fs.h>
#include <linux/version.h> #include <linux/version.h>
#include <stdio.h> #include <stdio.h>
@ -31,7 +32,12 @@
#include <sys/time.h> #include <sys/time.h>
#include <sys/types.h> #include <sys/types.h>
#include <unistd.h> #include <unistd.h>
#include <linux/usb/ch9.h>
#include <chrono>
#include <condition_variable>
#include <list>
#include <mutex>
#include <string>
#include <base/file.h> #include <base/file.h>
#include <base/stringprintf.h> #include <base/stringprintf.h>
@ -40,110 +46,92 @@
#include "adb.h" #include "adb.h"
#include "transport.h" #include "transport.h"
using namespace std::literals;
/* usb scan debugging is waaaay too verbose */ /* usb scan debugging is waaaay too verbose */
#define DBGX(x...) #define DBGX(x...)
ADB_MUTEX_DEFINE( usb_lock ); struct usb_handle {
~usb_handle() {
if (fd != -1) unix_close(fd);
}
struct usb_handle std::string path;
{ int fd = -1;
usb_handle *prev;
usb_handle *next;
char fname[64];
int desc;
unsigned char ep_in; unsigned char ep_in;
unsigned char ep_out; unsigned char ep_out;
unsigned zero_mask; unsigned zero_mask;
unsigned writeable; unsigned writeable = 1;
struct usbdevfs_urb urb_in; usbdevfs_urb urb_in;
struct usbdevfs_urb urb_out; usbdevfs_urb urb_out;
int urb_in_busy; bool urb_in_busy = false;
int urb_out_busy; bool urb_out_busy = false;
int dead; bool dead = false;
adb_cond_t notify; std::condition_variable cv;
adb_mutex_t lock; std::mutex mutex;
// for garbage collecting disconnected devices // for garbage collecting disconnected devices
int mark; bool mark;
// ID of thread currently in REAPURB // ID of thread currently in REAPURB
pthread_t reaper_thread; pthread_t reaper_thread = 0;
}; };
static usb_handle handle_list = { static std::mutex g_usb_handles_mutex;
.prev = &handle_list, static std::list<usb_handle*> g_usb_handles;
.next = &handle_list,
};
static int known_device(const char *dev_name) static int is_known_device(const char* dev_name) {
{ std::lock_guard<std::mutex> lock(g_usb_handles_mutex);
usb_handle *usb; for (usb_handle* usb : g_usb_handles) {
if (usb->path == dev_name) {
adb_mutex_lock(&usb_lock);
for(usb = handle_list.next; usb != &handle_list; usb = usb->next){
if(!strcmp(usb->fname, dev_name)) {
// set mark flag to indicate this device is still alive // set mark flag to indicate this device is still alive
usb->mark = 1; usb->mark = true;
adb_mutex_unlock(&usb_lock);
return 1; return 1;
} }
} }
adb_mutex_unlock(&usb_lock);
return 0; return 0;
} }
static void kick_disconnected_devices() static void kick_disconnected_devices() {
{ std::lock_guard<std::mutex> lock(g_usb_handles_mutex);
usb_handle *usb;
adb_mutex_lock(&usb_lock);
// kick any devices in the device list that were not found in the device scan // kick any devices in the device list that were not found in the device scan
for(usb = handle_list.next; usb != &handle_list; usb = usb->next){ for (usb_handle* usb : g_usb_handles) {
if (usb->mark == 0) { if (!usb->mark) {
usb_kick(usb); usb_kick(usb);
} else { } else {
usb->mark = 0; usb->mark = false;
} }
} }
adb_mutex_unlock(&usb_lock);
} }
static inline int badname(const char *name) static inline bool contains_non_digit(const char* name) {
{ while (*name) {
while(*name) { if (!isdigit(*name++)) return true;
if(!isdigit(*name++)) return 1;
} }
return 0; return false;
} }
static void find_usb_device(const char *base, static void find_usb_device(const std::string& base,
void (*register_device_callback) void (*register_device_callback)
(const char *, const char *, unsigned char, unsigned char, int, int, unsigned)) (const char*, const char*, unsigned char, unsigned char, int, int, unsigned))
{ {
char busname[32], devname[32]; std::unique_ptr<DIR, int(*)(DIR*)> bus_dir(opendir(base.c_str()), closedir);
unsigned char local_ep_in, local_ep_out; if (!bus_dir) return;
DIR *busdir , *devdir ;
struct dirent *de;
int fd ;
busdir = opendir(base); dirent* de;
if(busdir == 0) return; while ((de = readdir(bus_dir.get())) != 0) {
if (contains_non_digit(de->d_name)) continue;
while((de = readdir(busdir)) != 0) { std::string bus_name = base + "/" + de->d_name;
if(badname(de->d_name)) continue;
snprintf(busname, sizeof busname, "%s/%s", base, de->d_name); std::unique_ptr<DIR, int(*)(DIR*)> dev_dir(opendir(bus_name.c_str()), closedir);
devdir = opendir(busname); if (!dev_dir) continue;
if(devdir == 0) continue;
// DBGX("[ scanning %s ]\n", busname); while ((de = readdir(dev_dir.get()))) {
while((de = readdir(devdir))) {
unsigned char devdesc[4096]; unsigned char devdesc[4096];
unsigned char* bufptr = devdesc; unsigned char* bufptr = devdesc;
unsigned char* bufend; unsigned char* bufend;
@ -153,22 +141,20 @@ static void find_usb_device(const char *base,
struct usb_endpoint_descriptor *ep1, *ep2; struct usb_endpoint_descriptor *ep1, *ep2;
unsigned zero_mask = 0; unsigned zero_mask = 0;
unsigned vid, pid; unsigned vid, pid;
size_t desclength;
if(badname(de->d_name)) continue; if (contains_non_digit(de->d_name)) continue;
snprintf(devname, sizeof devname, "%s/%s", busname, de->d_name);
if(known_device(devname)) { std::string dev_name = bus_name + "/" + de->d_name;
DBGX("skipping %s\n", devname); if (is_known_device(dev_name.c_str())) {
continue; continue;
} }
// DBGX("[ scanning %s ]\n", devname); int fd = unix_open(dev_name.c_str(), O_RDONLY | O_CLOEXEC);
if((fd = unix_open(devname, O_RDONLY | O_CLOEXEC)) < 0) { if (fd == -1) {
continue; continue;
} }
desclength = unix_read(fd, devdesc, sizeof(devdesc)); size_t desclength = unix_read(fd, devdesc, sizeof(devdesc));
bufend = bufptr + desclength; bufend = bufptr + desclength;
// should have device and configuration descriptors, and atleast two endpoints // should have device and configuration descriptors, and atleast two endpoints
@ -188,7 +174,7 @@ static void find_usb_device(const char *base,
vid = device->idVendor; vid = device->idVendor;
pid = device->idProduct; pid = device->idProduct;
DBGX("[ %s is V:%04x P:%04x ]\n", devname, vid, pid); DBGX("[ %s is V:%04x P:%04x ]\n", dev_name.c_str(), vid, pid);
// should have config descriptor next // should have config descriptor next
config = (struct usb_config_descriptor *)bufptr; config = (struct usb_config_descriptor *)bufptr;
@ -225,7 +211,7 @@ static void find_usb_device(const char *base,
struct stat st; struct stat st;
char pathbuf[128]; char pathbuf[128];
char link[256]; char link[256];
char *devpath = NULL; char *devpath = nullptr;
DBGX("looking for bulk endpoints\n"); DBGX("looking for bulk endpoints\n");
// looks like ADB... // looks like ADB...
@ -267,6 +253,7 @@ static void find_usb_device(const char *base,
} }
// we have a match. now we just need to figure out which is in and which is out. // we have a match. now we just need to figure out which is in and which is out.
unsigned char local_ep_in, local_ep_out;
if (ep1->bEndpointAddress & USB_ENDPOINT_DIR_MASK) { if (ep1->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
local_ep_in = ep1->bEndpointAddress; local_ep_in = ep1->bEndpointAddress;
local_ep_out = ep2->bEndpointAddress; local_ep_out = ep2->bEndpointAddress;
@ -293,7 +280,7 @@ static void find_usb_device(const char *base,
} }
} }
register_device_callback(devname, devpath, register_device_callback(dev_name.c_str(), devpath,
local_ep_in, local_ep_out, local_ep_in, local_ep_out,
interface->bInterfaceNumber, device->iSerialNumber, zero_mask); interface->bInterfaceNumber, device->iSerialNumber, zero_mask);
break; break;
@ -304,72 +291,54 @@ static void find_usb_device(const char *base,
} // end of while } // end of while
unix_close(fd); unix_close(fd);
} // end of devdir while }
closedir(devdir); }
} //end of busdir while
closedir(busdir);
} }
static int usb_bulk_write(usb_handle *h, const void *data, int len) static int usb_bulk_write(usb_handle* h, const void* data, int len) {
{ std::unique_lock<std::mutex> lock(h->mutex);
struct usbdevfs_urb *urb = &h->urb_out; D("++ usb_bulk_write ++\n");
int res;
struct timeval tv;
struct timespec ts;
usbdevfs_urb* urb = &h->urb_out;
memset(urb, 0, sizeof(*urb)); memset(urb, 0, sizeof(*urb));
urb->type = USBDEVFS_URB_TYPE_BULK; urb->type = USBDEVFS_URB_TYPE_BULK;
urb->endpoint = h->ep_out; urb->endpoint = h->ep_out;
urb->status = -1; urb->status = -1;
urb->buffer = (void*) data; urb->buffer = const_cast<void*>(data);
urb->buffer_length = len; urb->buffer_length = len;
D("++ write ++\n"); if (h->dead) {
errno = EINVAL;
adb_mutex_lock(&h->lock); return -1;
if(h->dead) {
res = -1;
goto fail;
}
do {
res = ioctl(h->desc, USBDEVFS_SUBMITURB, urb);
} while((res < 0) && (errno == EINTR));
if(res < 0) {
goto fail;
} }
res = -1; if (TEMP_FAILURE_RETRY(ioctl(h->fd, USBDEVFS_SUBMITURB, urb)) == -1) {
h->urb_out_busy = 1; return -1;
for(;;) { }
/* time out after five seconds */
gettimeofday(&tv, NULL); h->urb_out_busy = true;
ts.tv_sec = tv.tv_sec + 5; while (true) {
ts.tv_nsec = tv.tv_usec * 1000L; auto now = std::chrono::system_clock::now();
res = pthread_cond_timedwait(&h->notify, &h->lock, &ts); if (h->cv.wait_until(lock, now + 5s) == std::cv_status::timeout || h->dead) {
if(res < 0 || h->dead) { // TODO: call USBDEVFS_DISCARDURB?
break; errno = ETIMEDOUT;
return -1;
} }
if(h->urb_out_busy == 0) { if (!h->urb_out_busy) {
if(urb->status == 0) { if (urb->status != 0) {
res = urb->actual_length; errno = -urb->status;
return -1;
} }
break; return urb->actual_length;
} }
} }
fail:
adb_mutex_unlock(&h->lock);
D("-- write --\n");
return res;
} }
static int usb_bulk_read(usb_handle *h, void *data, int len) static int usb_bulk_read(usb_handle* h, void* data, int len) {
{ std::unique_lock<std::mutex> lock(h->mutex);
struct usbdevfs_urb *urb = &h->urb_in;
struct usbdevfs_urb *out = NULL;
int res;
D("++ usb_bulk_read ++\n"); D("++ usb_bulk_read ++\n");
usbdevfs_urb* urb = &h->urb_in;
memset(urb, 0, sizeof(*urb)); memset(urb, 0, sizeof(*urb));
urb->type = USBDEVFS_URB_TYPE_BULK; urb->type = USBDEVFS_URB_TYPE_BULK;
urb->endpoint = h->ep_in; urb->endpoint = h->ep_in;
@ -377,63 +346,58 @@ static int usb_bulk_read(usb_handle *h, void *data, int len)
urb->buffer = data; urb->buffer = data;
urb->buffer_length = len; urb->buffer_length = len;
if (h->dead) {
adb_mutex_lock(&h->lock); errno = EINVAL;
if(h->dead) { return -1;
res = -1;
goto fail;
}
do {
res = ioctl(h->desc, USBDEVFS_SUBMITURB, urb);
} while((res < 0) && (errno == EINTR));
if(res < 0) {
goto fail;
} }
h->urb_in_busy = 1; if (TEMP_FAILURE_RETRY(ioctl(h->fd, USBDEVFS_SUBMITURB, urb)) == -1) {
for(;;) { return -1;
}
h->urb_in_busy = true;
while (true) {
D("[ reap urb - wait ]\n"); D("[ reap urb - wait ]\n");
h->reaper_thread = pthread_self(); h->reaper_thread = pthread_self();
adb_mutex_unlock(&h->lock); int fd = h->fd;
res = ioctl(h->desc, USBDEVFS_REAPURB, &out); lock.unlock();
// This ioctl must not have TEMP_FAILURE_RETRY because we send SIGALRM to break out.
usbdevfs_urb* out = nullptr;
int res = ioctl(fd, USBDEVFS_REAPURB, &out);
int saved_errno = errno; int saved_errno = errno;
adb_mutex_lock(&h->lock);
lock.lock();
h->reaper_thread = 0; h->reaper_thread = 0;
if(h->dead) { if (h->dead) {
res = -1; errno = EINVAL;
break; return -1;
} }
if(res < 0) { if (res < 0) {
if(saved_errno == EINTR) { if (saved_errno == EINTR) {
continue; continue;
} }
D("[ reap urb - error ]\n"); D("[ reap urb - error ]\n");
break; errno = saved_errno;
return -1;
} }
D("[ urb @%p status = %d, actual = %d ]\n", D("[ urb @%p status = %d, actual = %d ]\n", out, out->status, out->actual_length);
out, out->status, out->actual_length);
if(out == &h->urb_in) { if (out == &h->urb_in) {
D("[ reap urb - IN complete ]\n"); D("[ reap urb - IN complete ]\n");
h->urb_in_busy = 0; h->urb_in_busy = false;
if(urb->status == 0) { if (urb->status != 0) {
res = urb->actual_length; errno = -urb->status;
} else { return -1;
res = -1;
} }
break; return urb->actual_length;
} }
if(out == &h->urb_out) { if (out == &h->urb_out) {
D("[ reap urb - OUT compelete ]\n"); D("[ reap urb - OUT compelete ]\n");
h->urb_out_busy = 0; h->urb_out_busy = false;
adb_cond_broadcast(&h->notify); h->cv.notify_all();
} }
} }
fail:
adb_mutex_unlock(&h->lock);
D("-- usb_bulk_read --\n");
return res;
} }
@ -443,19 +407,15 @@ int usb_write(usb_handle *h, const void *_data, int len)
unsigned char *data = (unsigned char*) _data; unsigned char *data = (unsigned char*) _data;
int n = usb_bulk_write(h, data, len); int n = usb_bulk_write(h, data, len);
if(n != len) { if (n != len) {
D("ERROR: n = %d, errno = %d (%s)\n", D("ERROR: n = %d, errno = %d (%s)\n", n, errno, strerror(errno));
n, errno, strerror(errno));
return -1; return -1;
} }
if(h->zero_mask && !(len & h->zero_mask)) { if (h->zero_mask && !(len & h->zero_mask)) {
/* if we need 0-markers and our transfer // If we need 0-markers and our transfer is an even multiple of the packet size,
** is an even multiple of the packet size, // then send a zero marker.
** then send the zero markers. return usb_bulk_write(h, _data, 0);
*/
n = usb_bulk_write(h, _data, 0);
return n;
} }
D("-- usb_write --\n"); D("-- usb_write --\n");
@ -471,11 +431,11 @@ int usb_read(usb_handle *h, void *_data, int len)
while(len > 0) { while(len > 0) {
int xfer = len; int xfer = len;
D("[ usb read %d fd = %d], fname=%s\n", xfer, h->desc, h->fname); D("[ usb read %d fd = %d], path=%s\n", xfer, h->fd, h->path.c_str());
n = usb_bulk_read(h, data, xfer); n = usb_bulk_read(h, data, xfer);
D("[ usb read %d ] = %d, fname=%s\n", xfer, n, h->fname); D("[ usb read %d ] = %d, path=%s\n", xfer, n, h->path.c_str());
if(n != xfer) { if(n != xfer) {
if((errno == ETIMEDOUT) && (h->desc != -1)) { if((errno == ETIMEDOUT) && (h->fd != -1)) {
D("[ timeout ]\n"); D("[ timeout ]\n");
if(n > 0){ if(n > 0){
data += n; data += n;
@ -496,12 +456,11 @@ int usb_read(usb_handle *h, void *_data, int len)
return 0; return 0;
} }
void usb_kick(usb_handle *h) void usb_kick(usb_handle* h) {
{ std::lock_guard<std::mutex> lock(h->mutex);
D("[ kicking %p (fd = %d) ]\n", h, h->desc); D("[ kicking %p (fd = %d) ]\n", h, h->fd);
adb_mutex_lock(&h->lock); if (!h->dead) {
if(h->dead == 0) { h->dead = true;
h->dead = 1;
if (h->writeable) { if (h->writeable) {
/* HACK ALERT! /* HACK ALERT!
@ -517,34 +476,27 @@ void usb_kick(usb_handle *h)
** but this ensures that a reader blocked on REAPURB ** but this ensures that a reader blocked on REAPURB
** will get unblocked ** will get unblocked
*/ */
ioctl(h->desc, USBDEVFS_DISCARDURB, &h->urb_in); ioctl(h->fd, USBDEVFS_DISCARDURB, &h->urb_in);
ioctl(h->desc, USBDEVFS_DISCARDURB, &h->urb_out); ioctl(h->fd, USBDEVFS_DISCARDURB, &h->urb_out);
h->urb_in.status = -ENODEV; h->urb_in.status = -ENODEV;
h->urb_out.status = -ENODEV; h->urb_out.status = -ENODEV;
h->urb_in_busy = 0; h->urb_in_busy = false;
h->urb_out_busy = 0; h->urb_out_busy = false;
adb_cond_broadcast(&h->notify); h->cv.notify_all();
} else { } else {
unregister_usb_transport(h); unregister_usb_transport(h);
} }
} }
adb_mutex_unlock(&h->lock);
} }
int usb_close(usb_handle *h) int usb_close(usb_handle* h) {
{ std::lock_guard<std::mutex> lock(g_usb_handles_mutex);
D("++ usb close ++\n"); g_usb_handles.remove(h);
adb_mutex_lock(&usb_lock);
h->next->prev = h->prev;
h->prev->next = h->next;
h->prev = 0;
h->next = 0;
unix_close(h->desc); D("-- usb close %p (fd = %d) --\n", h, h->fd);
D("-- usb closed %p (fd = %d) --\n", h, h->desc);
adb_mutex_unlock(&usb_lock); delete h;
free(h);
return 0; return 0;
} }
@ -557,54 +509,44 @@ static void register_device(const char* dev_name, const char* dev_path,
// from the list when we're finally closed and everything will work out // from the list when we're finally closed and everything will work out
// fine. // fine.
// //
// If we have a usb_handle on the list 'o handles with a matching name, we // If we have a usb_handle on the list of handles with a matching name, we
// have no further work to do. // have no further work to do.
adb_mutex_lock(&usb_lock); {
for (usb_handle* usb = handle_list.next; usb != &handle_list; usb = usb->next) { std::lock_guard<std::mutex> lock(g_usb_handles_mutex);
if (!strcmp(usb->fname, dev_name)) { for (usb_handle* usb: g_usb_handles) {
adb_mutex_unlock(&usb_lock); if (usb->path == dev_name) {
return; return;
}
} }
} }
adb_mutex_unlock(&usb_lock);
D("[ usb located new device %s (%d/%d/%d) ]\n", dev_name, ep_in, ep_out, interface); D("[ usb located new device %s (%d/%d/%d) ]\n", dev_name, ep_in, ep_out, interface);
usb_handle* usb = reinterpret_cast<usb_handle*>(calloc(1, sizeof(usb_handle))); std::unique_ptr<usb_handle> usb(new usb_handle);
if (usb == nullptr) fatal("couldn't allocate usb_handle"); usb->path = dev_name;
strcpy(usb->fname, dev_name);
usb->ep_in = ep_in; usb->ep_in = ep_in;
usb->ep_out = ep_out; usb->ep_out = ep_out;
usb->zero_mask = zero_mask; usb->zero_mask = zero_mask;
usb->writeable = 1;
adb_cond_init(&usb->notify, 0); // Initialize mark so we don't get garbage collected after the device scan.
adb_mutex_init(&usb->lock, 0); usb->mark = true;
// Initialize mark to 1 so we don't get garbage collected after the device
// scan.
usb->mark = 1;
usb->reaper_thread = 0;
usb->desc = unix_open(usb->fname, O_RDWR | O_CLOEXEC); usb->fd = unix_open(usb->path.c_str(), O_RDWR | O_CLOEXEC);
if (usb->desc == -1) { if (usb->fd == -1) {
// Opening RW failed, so see if we have RO access. // Opening RW failed, so see if we have RO access.
usb->desc = unix_open(usb->fname, O_RDONLY | O_CLOEXEC); usb->fd = unix_open(usb->path.c_str(), O_RDONLY | O_CLOEXEC);
if (usb->desc == -1) { if (usb->fd == -1) {
D("[ usb open %s failed: %s]\n", usb->fname, strerror(errno)); D("[ usb open %s failed: %s]\n", usb->path.c_str(), strerror(errno));
free(usb);
return; return;
} }
usb->writeable = 0; usb->writeable = 0;
} }
D("[ usb opened %s%s, fd=%d]\n", usb->fname, D("[ usb opened %s%s, fd=%d]\n",
(usb->writeable ? "" : " (read-only)"), usb->desc); usb->path.c_str(), (usb->writeable ? "" : " (read-only)"), usb->fd);
if (usb->writeable) { if (usb->writeable) {
if (ioctl(usb->desc, USBDEVFS_CLAIMINTERFACE, &interface) != 0) { if (ioctl(usb->fd, USBDEVFS_CLAIMINTERFACE, &interface) != 0) {
D("[ usb ioctl(%d, USBDEVFS_CLAIMINTERFACE) failed: %s]\n", D("[ usb ioctl(%d, USBDEVFS_CLAIMINTERFACE) failed: %s]\n", usb->fd, strerror(errno));
usb->desc, strerror(errno));
unix_close(usb->desc);
free(usb);
return; return;
} }
} }
@ -623,14 +565,12 @@ static void register_device(const char* dev_name, const char* dev_path,
serial = android::base::Trim(serial); serial = android::base::Trim(serial);
// Add to the end of the active handles. // Add to the end of the active handles.
adb_mutex_lock(&usb_lock); usb_handle* done_usb = usb.release();
usb->next = &handle_list; {
usb->prev = handle_list.prev; std::lock_guard<std::mutex> lock(g_usb_handles_mutex);
usb->prev->next = usb; g_usb_handles.push_back(done_usb);
usb->next->prev = usb; }
adb_mutex_unlock(&usb_lock); register_usb_transport(done_usb, serial.c_str(), dev_path, done_usb->writeable);
register_usb_transport(usb, serial.c_str(), dev_path, usb->writeable);
} }
static void* device_poll_thread(void* unused) { static void* device_poll_thread(void* unused) {
@ -644,19 +584,13 @@ static void* device_poll_thread(void* unused) {
return nullptr; return nullptr;
} }
static void sigalrm_handler(int signo) { void usb_init() {
// don't need to do anything here struct sigaction actions;
}
void usb_init()
{
struct sigaction actions;
memset(&actions, 0, sizeof(actions)); memset(&actions, 0, sizeof(actions));
sigemptyset(&actions.sa_mask); sigemptyset(&actions.sa_mask);
actions.sa_flags = 0; actions.sa_flags = 0;
actions.sa_handler = sigalrm_handler; actions.sa_handler = [](int) {};
sigaction(SIGALRM,& actions, NULL); sigaction(SIGALRM, &actions, nullptr);
if (!adb_thread_create(device_poll_thread, nullptr)) { if (!adb_thread_create(device_poll_thread, nullptr)) {
fatal_errno("cannot create input thread"); fatal_errno("cannot create input thread");