win32-related misc patches

-----BEGIN PGP SIGNATURE-----
 
 iQJPBAABCAA6FiEEh6m9kz+HxgbSdvYt2ujhCXWWnOUFAmNG488cHG1hcmNhbmRy
 ZS5sdXJlYXVAcmVkaGF0LmNvbQAKCRDa6OEJdZac5eQTD/j/rEcONwL4gZn/Rcp8
 aJlr39GEHo0JxBAF3eoxCLJlebPcdaUQ4pu/FTegS1A4abPaajDH7rdtcA58ciAG
 rCQjUOrobHzxmI9XaTIPT4PQh3DA4HB58rTpAvb/6P/UDRc0MpkcvaOkGlJVhi+7
 WB63+gnQOBEjcieNcQtmRwYRkx7K5/9G4qEESl0i2E+SE4DM+/vcVa7lfqEZ+6HS
 bsDy2BslxtPFmHj1UElwXjTbCs4Y7pfTFd+9z8ySsGL1Komf45MZs0iS4FmZLqL/
 7Cuj+xRWibnPN9jnAc+Sdua3FAFZbqmfPQaH6DN6SICZ6Txf2hxFkAgTahagcxYX
 9EiKGHZzI4L3l/YAxFg9RfK+AsF44ZLPId58AVvUnG1jWwxl3nRaTmvtvHaEwJuZ
 PgnbAdsNzQAJjLnk8ndpTq4mQFM+9/mrQo+iaOCwmB5s07woyEq+L+KJHMUgyk2D
 lECn3vlqVGGb6GA6MS5gSXh0TDRxPxLyr9ofIG5i5YaTo4nH56S80tHrzZMUYNKD
 xe2yUrEZ7UjeV4/6M19xdw3haPOdrG3BoBshb61vI1bF/4iQxYNo8AxptCRhzNNM
 5Jrn/gyt47SEgMYpGIvHa/qo1lQiLsQAVKAK3O2QWd5T58V6J1a804zhTuT7T45O
 kZS2c8XEdAiBtUAkYNgFxwGM
 =Lpqm
 -----END PGP SIGNATURE-----

Merge tag 'win32-pull-request' of https://gitlab.com/marcandre.lureau/qemu into staging

win32-related misc patches

# -----BEGIN PGP SIGNATURE-----
#
# iQJPBAABCAA6FiEEh6m9kz+HxgbSdvYt2ujhCXWWnOUFAmNG488cHG1hcmNhbmRy
# ZS5sdXJlYXVAcmVkaGF0LmNvbQAKCRDa6OEJdZac5eQTD/j/rEcONwL4gZn/Rcp8
# aJlr39GEHo0JxBAF3eoxCLJlebPcdaUQ4pu/FTegS1A4abPaajDH7rdtcA58ciAG
# rCQjUOrobHzxmI9XaTIPT4PQh3DA4HB58rTpAvb/6P/UDRc0MpkcvaOkGlJVhi+7
# WB63+gnQOBEjcieNcQtmRwYRkx7K5/9G4qEESl0i2E+SE4DM+/vcVa7lfqEZ+6HS
# bsDy2BslxtPFmHj1UElwXjTbCs4Y7pfTFd+9z8ySsGL1Komf45MZs0iS4FmZLqL/
# 7Cuj+xRWibnPN9jnAc+Sdua3FAFZbqmfPQaH6DN6SICZ6Txf2hxFkAgTahagcxYX
# 9EiKGHZzI4L3l/YAxFg9RfK+AsF44ZLPId58AVvUnG1jWwxl3nRaTmvtvHaEwJuZ
# PgnbAdsNzQAJjLnk8ndpTq4mQFM+9/mrQo+iaOCwmB5s07woyEq+L+KJHMUgyk2D
# lECn3vlqVGGb6GA6MS5gSXh0TDRxPxLyr9ofIG5i5YaTo4nH56S80tHrzZMUYNKD
# xe2yUrEZ7UjeV4/6M19xdw3haPOdrG3BoBshb61vI1bF/4iQxYNo8AxptCRhzNNM
# 5Jrn/gyt47SEgMYpGIvHa/qo1lQiLsQAVKAK3O2QWd5T58V6J1a804zhTuT7T45O
# kZS2c8XEdAiBtUAkYNgFxwGM
# =Lpqm
# -----END PGP SIGNATURE-----
# gpg: Signature made Wed 12 Oct 2022 11:57:03 EDT
# gpg:                using RSA key 87A9BD933F87C606D276F62DDAE8E10975969CE5
# gpg:                issuer "marcandre.lureau@redhat.com"
# gpg: Good signature from "Marc-André Lureau <marcandre.lureau@redhat.com>" [full]
# gpg:                 aka "Marc-André Lureau <marcandre.lureau@gmail.com>" [full]
# Primary key fingerprint: 87A9 BD93 3F87 C606 D276  F62D DAE8 E109 7596 9CE5

* tag 'win32-pull-request' of https://gitlab.com/marcandre.lureau/qemu:
  tests/unit: make test-io-channel-command work on win32
  io/command: implement support for win32
  io/command: use glib GSpawn, instead of open-coding fork/exec
  tests/channel-helper: set blocking in main thread
  util: make do_send_recv work with partial send/recv
  osdep: make readv_writev() work with partial read/write
  win32: set threads name

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

include/io/channel-command.h

@@ -41,7 +41,10 @@ struct QIOChannelCommand {
     QIOChannel parent;
     int writefd;
     int readfd;
-    pid_t pid;
+    GPid pid;
+#ifdef WIN32
+    bool blocking;
+#endif
 };
 
 

io/channel-command.c

@@ -26,12 +26,11 @@
 #include "qemu/sockets.h"
 #include "trace.h"
 
-#ifndef WIN32
 /**
  * qio_channel_command_new_pid:
  * @writefd: the FD connected to the command's stdin
  * @readfd: the FD connected to the command's stdout
- * @pid: the PID of the running child command
+ * @pid: the PID/HANDLE of the running child command
  * @errp: pointer to a NULL-initialized error object
  *
  * Create a channel for performing I/O with the
@@ -50,7 +49,7 @@
 static QIOChannelCommand *
 qio_channel_command_new_pid(int writefd,
                             int readfd,
-                            pid_t pid)
+                            GPid pid)
 {
     QIOChannelCommand *ioc;
 
@@ -60,7 +59,13 @@ qio_channel_command_new_pid(int writefd,
     ioc->writefd = writefd;
     ioc->pid = pid;
 
-    trace_qio_channel_command_new_pid(ioc, writefd, readfd, pid);
+    trace_qio_channel_command_new_pid(ioc, writefd, readfd,
+#ifdef WIN32
+                                      GetProcessId(pid)
+#else
+                                      pid
+#endif
+        );
     return ioc;
 }
 
@@ -69,108 +74,26 @@ qio_channel_command_new_spawn(const char *const argv[],
                               int flags,
                               Error **errp)
 {
-    pid_t pid = -1;
+    g_autoptr(GError) err = NULL;
-    int stdinfd[2] = { -1, -1 };
+    GPid pid = 0;
-    int stdoutfd[2] = { -1, -1 };
+    GSpawnFlags gflags = G_SPAWN_CLOEXEC_PIPES | G_SPAWN_DO_NOT_REAP_CHILD;
-    int devnull = -1;
+    int stdinfd = -1, stdoutfd = -1;
-    bool stdinnull = false, stdoutnull = false;
-    QIOChannelCommand *ioc;
 
     flags = flags & O_ACCMODE;
+    gflags |= flags == O_WRONLY ? G_SPAWN_STDOUT_TO_DEV_NULL : 0;
 
-    if (flags == O_RDONLY) {
+    if (!g_spawn_async_with_pipes(NULL, (char **)argv, NULL, gflags, NULL, NULL,
-        stdinnull = true;
+                                  &pid,
-    }
+                                  flags == O_RDONLY ? NULL : &stdinfd,
-    if (flags == O_WRONLY) {
+                                  flags == O_WRONLY ? NULL : &stdoutfd,
-        stdoutnull = true;
+                                  NULL, &err)) {
+        error_setg(errp, "%s", err->message);
+        return NULL;
     }
 
-    if (stdinnull || stdoutnull) {
+    return qio_channel_command_new_pid(stdinfd, stdoutfd, pid);
-        devnull = open("/dev/null", O_RDWR);
-        if (devnull < 0) {
-            error_setg_errno(errp, errno,
-                             "Unable to open /dev/null");
-            goto error;
-        }
-    }
-
-    if ((!stdinnull && !g_unix_open_pipe(stdinfd, FD_CLOEXEC, NULL)) ||
-        (!stdoutnull && !g_unix_open_pipe(stdoutfd, FD_CLOEXEC, NULL))) {
-        error_setg_errno(errp, errno,
-                         "Unable to open pipe");
-        goto error;
-    }
-
-    pid = qemu_fork(errp);
-    if (pid < 0) {
-        goto error;
-    }
-
-    if (pid == 0) { /* child */
-        dup2(stdinnull ? devnull : stdinfd[0], STDIN_FILENO);
-        dup2(stdoutnull ? devnull : stdoutfd[1], STDOUT_FILENO);
-        /* Leave stderr connected to qemu's stderr */
-
-        if (!stdinnull) {
-            close(stdinfd[0]);
-            close(stdinfd[1]);
-        }
-        if (!stdoutnull) {
-            close(stdoutfd[0]);
-            close(stdoutfd[1]);
-        }
-        if (devnull != -1) {
-            close(devnull);
-        }
-
-        execv(argv[0], (char * const *)argv);
-        _exit(1);
-    }
-
-    if (!stdinnull) {
-        close(stdinfd[0]);
-    }
-    if (!stdoutnull) {
-        close(stdoutfd[1]);
-    }
-
-    ioc = qio_channel_command_new_pid(stdinnull ? devnull : stdinfd[1],
-                                      stdoutnull ? devnull : stdoutfd[0],
-                                      pid);
-    trace_qio_channel_command_new_spawn(ioc, argv[0], flags);
-    return ioc;
-
- error:
-    if (devnull != -1) {
-        close(devnull);
-    }
-    if (stdinfd[0] != -1) {
-        close(stdinfd[0]);
-    }
-    if (stdinfd[1] != -1) {
-        close(stdinfd[1]);
-    }
-    if (stdoutfd[0] != -1) {
-        close(stdoutfd[0]);
-    }
-    if (stdoutfd[1] != -1) {
-        close(stdoutfd[1]);
-    }
-    return NULL;
 }
 
-#else /* WIN32 */
-QIOChannelCommand *
-qio_channel_command_new_spawn(const char *const argv[],
-                              int flags,
-                              Error **errp)
-{
-    error_setg_errno(errp, ENOSYS,
-                     "Command spawn not supported on this platform");
-    return NULL;
-}
-#endif /* WIN32 */
-
 #ifndef WIN32
 static int qio_channel_command_abort(QIOChannelCommand *ioc,
                                      Error **errp)
@@ -213,6 +136,23 @@ static int qio_channel_command_abort(QIOChannelCommand *ioc,
 
     return 0;
 }
+#else
+static int qio_channel_command_abort(QIOChannelCommand *ioc,
+                                     Error **errp)
+{
+    DWORD ret;
+
+    TerminateProcess(ioc->pid, 0);
+    ret = WaitForSingleObject(ioc->pid, 1000);
+    if (ret != WAIT_OBJECT_0) {
+        error_setg(errp,
+                   "Process %llu refused to die",
+                   (unsigned long long)GetProcessId(ioc->pid));
+        return -1;
+    }
+
+    return 0;
+}
 #endif /* ! WIN32 */
 
 
@@ -221,7 +161,7 @@ static void qio_channel_command_init(Object *obj)
     QIOChannelCommand *ioc = QIO_CHANNEL_COMMAND(obj);
     ioc->readfd = -1;
     ioc->writefd = -1;
-    ioc->pid = -1;
+    ioc->pid = 0;
 }
 
 static void qio_channel_command_finalize(Object *obj)
@@ -236,12 +176,27 @@ static void qio_channel_command_finalize(Object *obj)
     }
     ioc->writefd = ioc->readfd = -1;
     if (ioc->pid > 0) {
-#ifndef WIN32
         qio_channel_command_abort(ioc, NULL);
-#endif
+        g_spawn_close_pid(ioc->pid);
     }
 }
 
+#ifdef WIN32
+static bool win32_fd_poll(int fd, gushort events)
+{
+    GPollFD pfd = { .fd = _get_osfhandle(fd), .events = events };
+    int res;
+
+    do {
+        res = g_poll(&pfd, 1, 0);
+    } while (res < 0 && errno == EINTR);
+    if (res == 0) {
+        return false;
+    }
+
+    return true;
+}
+#endif
 
 static ssize_t qio_channel_command_readv(QIOChannel *ioc,
                                          const struct iovec *iov,
@@ -253,6 +208,12 @@ static ssize_t qio_channel_command_readv(QIOChannel *ioc,
     QIOChannelCommand *cioc = QIO_CHANNEL_COMMAND(ioc);
     ssize_t ret;
 
+#ifdef WIN32
+    if (!cioc->blocking && !win32_fd_poll(cioc->readfd, G_IO_IN)) {
+        return QIO_CHANNEL_ERR_BLOCK;
+    }
+#endif
+
  retry:
     ret = readv(cioc->readfd, iov, niov);
     if (ret < 0) {
@@ -282,6 +243,12 @@ static ssize_t qio_channel_command_writev(QIOChannel *ioc,
     QIOChannelCommand *cioc = QIO_CHANNEL_COMMAND(ioc);
     ssize_t ret;
 
+#ifdef WIN32
+    if (!cioc->blocking && !win32_fd_poll(cioc->writefd, G_IO_OUT)) {
+        return QIO_CHANNEL_ERR_BLOCK;
+    }
+#endif
+
  retry:
     ret = writev(cioc->writefd, iov, niov);
     if (ret <= 0) {
@@ -302,14 +269,14 @@ static int qio_channel_command_set_blocking(QIOChannel *ioc,
                                             bool enabled,
                                             Error **errp)
 {
-#ifdef WIN32
-    /* command spawn is not supported on win32 */
-    g_assert_not_reached();
-#else
     QIOChannelCommand *cioc = QIO_CHANNEL_COMMAND(ioc);
 
-    if (!g_unix_set_fd_nonblocking(cioc->writefd, !enabled, NULL) ||
+#ifdef WIN32
-        !g_unix_set_fd_nonblocking(cioc->readfd, !enabled, NULL)) {
+    cioc->blocking = enabled;
+#else
+
+    if ((cioc->writefd >= 0 && !g_unix_set_fd_nonblocking(cioc->writefd, !enabled, NULL)) ||
+        (cioc->readfd >= 0 && !g_unix_set_fd_nonblocking(cioc->readfd, !enabled, NULL))) {
         error_setg_errno(errp, errno, "Failed to set FD nonblocking");
         return -1;
     }
@@ -350,6 +317,8 @@ static int qio_channel_command_close(QIOChannel *ioc,
                          (unsigned long long)cioc->pid);
         return -1;
     }
+#else
+    WaitForSingleObject(cioc->pid, INFINITE);
 #endif
 
     if (rv < 0) {

tests/unit/io-channel-helpers.c

@@ -25,7 +25,6 @@
 struct QIOChannelTest {
     QIOChannel *src;
     QIOChannel *dst;
-    bool blocking;
     size_t len;
     size_t niov;
     char *input;
@@ -42,8 +41,6 @@ static gpointer test_io_thread_writer(gpointer opaque)
 {
     QIOChannelTest *data = opaque;
 
-    qio_channel_set_blocking(data->src, data->blocking, NULL);
-
     qio_channel_writev_all(data->src,
                            data->inputv,
                            data->niov,
@@ -58,8 +55,6 @@ static gpointer test_io_thread_reader(gpointer opaque)
 {
     QIOChannelTest *data = opaque;
 
-    qio_channel_set_blocking(data->dst, data->blocking, NULL);
-
     qio_channel_readv_all(data->dst,
                           data->outputv,
                           data->niov,
@@ -113,7 +108,9 @@ void qio_channel_test_run_threads(QIOChannelTest *test,
 
     test->src = src;
     test->dst = dst;
-    test->blocking = blocking;
+
+    qio_channel_set_blocking(test->dst, blocking, NULL);
+    qio_channel_set_blocking(test->src, blocking, NULL);
 
     reader = g_thread_new("reader",
                           test_io_thread_reader,

tests/unit/test-io-channel-command.c

@@ -24,29 +24,30 @@
 #include "qapi/error.h"
 #include "qemu/module.h"
 
-#ifndef WIN32
+#define TEST_FIFO "test-io-channel-command.fifo"
+
+#define SOCAT_SRC "PIPE:" TEST_FIFO ",wronly"
+#define SOCAT_DST "PIPE:" TEST_FIFO ",rdonly"
+
+static char *socat = NULL;
+
 static void test_io_channel_command_fifo(bool async)
 {
-#define TEST_FIFO "tests/test-io-channel-command.fifo"
     QIOChannel *src, *dst;
     QIOChannelTest *test;
-    const char *srcfifo = "PIPE:" TEST_FIFO ",wronly";
-    const char *dstfifo = "PIPE:" TEST_FIFO ",rdonly";
     const char *srcargv[] = {
-        "/bin/socat", "-", srcfifo, NULL,
+        socat, "-", SOCAT_SRC, NULL,
     };
     const char *dstargv[] = {
-        "/bin/socat", dstfifo, "-", NULL,
+        socat, SOCAT_DST, "-", NULL,
     };
 
-    unlink(TEST_FIFO);
+    if (!socat) {
-    if (access("/bin/socat", X_OK) < 0) {
+        g_test_skip("socat is not found in PATH");
-        g_test_skip("socat is missing");
         return;
     }
-    if (mkfifo(TEST_FIFO, 0600) < 0) {
+
-        abort();
+    unlink(TEST_FIFO);
-    }
     src = QIO_CHANNEL(qio_channel_command_new_spawn(srcargv,
                                                     O_WRONLY,
                                                     &error_abort));
@@ -81,11 +82,12 @@ static void test_io_channel_command_echo(bool async)
     QIOChannel *ioc;
     QIOChannelTest *test;
     const char *socatargv[] = {
-        "/bin/socat", "-", "-", NULL,
+        socat, "-", "-", NULL,
     };
 
-    if (access("/bin/socat", X_OK) < 0) {
+    if (!socat) {
-        return; /* Pretend success if socat is not present */
+        g_test_skip("socat is not found in PATH");
+        return;
     }
 
     ioc = QIO_CHANNEL(qio_channel_command_new_spawn(socatargv,
@@ -108,7 +110,6 @@ static void test_io_channel_command_echo_sync(void)
 {
     test_io_channel_command_echo(false);
 }
-#endif
 
 int main(int argc, char **argv)
 {
@@ -116,7 +117,8 @@ int main(int argc, char **argv)
 
     g_test_init(&argc, &argv, NULL);
 
-#ifndef WIN32
+    socat = g_find_program_in_path("socat");
+
     g_test_add_func("/io/channel/command/fifo/sync",
                     test_io_channel_command_fifo_sync);
     g_test_add_func("/io/channel/command/fifo/async",
@@ -125,7 +127,6 @@ int main(int argc, char **argv)
                     test_io_channel_command_echo_sync);
     g_test_add_func("/io/channel/command/echo/async",
                     test_io_channel_command_echo_async);
-#endif
 
     return g_test_run();
 }

util/iov.c

@@ -111,12 +111,17 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
     /*XXX Note: windows has WSASend() and WSARecv() */
     unsigned i = 0;
     ssize_t ret = 0;
+    ssize_t off = 0;
     while (i < iov_cnt) {
         ssize_t r = do_send
-            ? send(sockfd, iov[i].iov_base, iov[i].iov_len, 0)
+            ? send(sockfd, iov[i].iov_base + off, iov[i].iov_len - off, 0)
-            : recv(sockfd, iov[i].iov_base, iov[i].iov_len, 0);
+            : recv(sockfd, iov[i].iov_base + off, iov[i].iov_len - off, 0);
         if (r > 0) {
             ret += r;
+            off += r;
+            if (off < iov[i].iov_len) {
+                continue;
+            }
         } else if (!r) {
             break;
         } else if (errno == EINTR) {
@@ -129,6 +134,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
             }
             break;
         }
+        off = 0;
         i++;
     }
     return ret;

util/osdep.c

@@ -538,18 +538,22 @@ int socket_init(void)
 
 
 #ifndef CONFIG_IOVEC
-/* helper function for iov_send_recv() */
 static ssize_t
 readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write)
 {
     unsigned i = 0;
     ssize_t ret = 0;
+    ssize_t off = 0;
     while (i < iov_cnt) {
         ssize_t r = do_write
-            ? write(fd, iov[i].iov_base, iov[i].iov_len)
+            ? write(fd, iov[i].iov_base + off, iov[i].iov_len - off)
-            : read(fd, iov[i].iov_base, iov[i].iov_len);
+            : read(fd, iov[i].iov_base + off, iov[i].iov_len - off);
         if (r > 0) {
             ret += r;
+            off += r;
+            if (off < iov[i].iov_len) {
+                continue;
+            }
         } else if (!r) {
             break;
         } else if (errno == EINTR) {
@@ -562,6 +566,7 @@ readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write)
             }
             break;
         }
+        off = 0;
         i++;
     }
     return ret;

util/qemu-thread-win32.c

@@ -19,12 +19,39 @@
 
 static bool name_threads;
 
+typedef HRESULT (WINAPI *pSetThreadDescription) (HANDLE hThread,
+                                                 PCWSTR lpThreadDescription);
+static pSetThreadDescription SetThreadDescriptionFunc;
+static HMODULE kernel32_module;
+
+static bool load_set_thread_description(void)
+{
+    static gsize _init_once = 0;
+
+    if (g_once_init_enter(&_init_once)) {
+        kernel32_module = LoadLibrary("kernel32.dll");
+        if (kernel32_module) {
+            SetThreadDescriptionFunc =
+                (pSetThreadDescription)GetProcAddress(kernel32_module,
+                                                      "SetThreadDescription");
+            if (!SetThreadDescriptionFunc) {
+                FreeLibrary(kernel32_module);
+            }
+        }
+        g_once_init_leave(&_init_once, 1);
+    }
+
+    return !!SetThreadDescriptionFunc;
+}
+
 void qemu_thread_naming(bool enable)
 {
-    /* But note we don't actually name them on Windows yet */
     name_threads = enable;
 
-    fprintf(stderr, "qemu: thread naming not supported on this host\n");
+    if (enable && !load_set_thread_description()) {
+        fprintf(stderr, "qemu: thread naming not supported on this host\n");
+        name_threads = false;
+    }
 }
 
 static void error_exit(int err, const char *msg)
@@ -400,6 +427,25 @@ void *qemu_thread_join(QemuThread *thread)
     return ret;
 }
 
+static bool set_thread_description(HANDLE h, const char *name)
+{
+    HRESULT hr;
+    g_autofree wchar_t *namew = NULL;
+
+    if (!load_set_thread_description()) {
+        return false;
+    }
+
+    namew = g_utf8_to_utf16(name, -1, NULL, NULL, NULL);
+    if (!namew) {
+        return false;
+    }
+
+    hr = SetThreadDescriptionFunc(h, namew);
+
+    return SUCCEEDED(hr);
+}
+
 void qemu_thread_create(QemuThread *thread, const char *name,
                        void *(*start_routine)(void *),
                        void *arg, int mode)
@@ -423,7 +469,11 @@ void qemu_thread_create(QemuThread *thread, const char *name,
     if (!hThread) {
         error_exit(GetLastError(), __func__);
     }
+    if (name_threads && name && !set_thread_description(hThread, name)) {
+        fprintf(stderr, "qemu: failed to set thread description: %s\n", name);
+    }
     CloseHandle(hThread);
+
     thread->data = data;
 }