qemu-char: introduce qemu_chr_alloc

The next patch will modify this function to initialize state that is
common to all backends.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

backends/baum.c

@@ -574,7 +574,7 @@ CharDriverState *chr_baum_init(void)
     int tty;
 
     baum = g_malloc0(sizeof(BaumDriverState));
-    baum->chr = chr = g_malloc0(sizeof(CharDriverState));
+    baum->chr = chr = qemu_chr_alloc();
 
     chr->opaque = baum;
     chr->chr_write = baum_write;

backends/msmouse.c

@@ -67,7 +67,7 @@ CharDriverState *qemu_chr_open_msmouse(void)
 {
     CharDriverState *chr;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     chr->chr_write = msmouse_chr_write;
     chr->chr_close = msmouse_chr_close;
     chr->explicit_be_open = true;

include/sysemu/char.h

@@ -88,6 +88,15 @@ struct CharDriverState {
     QTAILQ_ENTRY(CharDriverState) next;
 };
 
+/**
+ * @qemu_chr_alloc:
+ *
+ * Allocate and initialize a new CharDriverState.
+ *
+ * Returns: a newly allocated CharDriverState.
+ */
+CharDriverState *qemu_chr_alloc(void);
+
 /**
  * @qemu_chr_new_from_opts:
  *

qemu-char.c

@@ -91,6 +91,12 @@
 static QTAILQ_HEAD(CharDriverStateHead, CharDriverState) chardevs =
     QTAILQ_HEAD_INITIALIZER(chardevs);
 
+CharDriverState *qemu_chr_alloc(void)
+{
+    CharDriverState *chr = g_malloc0(sizeof(CharDriverState));
+    return chr;
+}
+
 void qemu_chr_be_event(CharDriverState *s, int event)
 {
     /* Keep track if the char device is open */
@@ -282,7 +288,7 @@ static CharDriverState *qemu_chr_open_null(void)
 {
     CharDriverState *chr;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     chr->chr_write = null_chr_write;
     chr->explicit_be_open = true;
     return chr;
@@ -570,7 +576,7 @@ static CharDriverState *qemu_chr_open_mux(CharDriverState *drv)
     CharDriverState *chr;
     MuxDriver *d;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     d = g_malloc0(sizeof(MuxDriver));
 
     chr->opaque = d;
@@ -945,7 +951,7 @@ static CharDriverState *qemu_chr_open_fd(int fd_in, int fd_out)
     CharDriverState *chr;
     FDCharDriver *s;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(FDCharDriver));
     s->fd_in = io_channel_from_fd(fd_in);
     s->fd_out = io_channel_from_fd(fd_out);
@@ -1222,7 +1228,7 @@ static CharDriverState *qemu_chr_open_pty(const char *id,
 
     close(slave_fd);
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
 
     chr->filename = g_strdup_printf("pty:%s", pty_name);
     ret->pty = g_strdup(pty_name);
@@ -1584,7 +1590,7 @@ static CharDriverState *qemu_chr_open_pp_fd(int fd)
     drv->fd = fd;
     drv->mode = IEEE1284_MODE_COMPAT;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     chr->chr_write = null_chr_write;
     chr->chr_ioctl = pp_ioctl;
     chr->chr_close = pp_close;
@@ -1639,7 +1645,7 @@ static CharDriverState *qemu_chr_open_pp_fd(int fd)
 {
     CharDriverState *chr;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     chr->opaque = (void *)(intptr_t)fd;
     chr->chr_write = null_chr_write;
     chr->chr_ioctl = pp_ioctl;
@@ -1863,7 +1869,7 @@ static CharDriverState *qemu_chr_open_win_path(const char *filename)
     CharDriverState *chr;
     WinCharState *s;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(WinCharState));
     chr->opaque = s;
     chr->chr_write = win_chr_write;
@@ -1962,7 +1968,7 @@ static CharDriverState *qemu_chr_open_pipe(ChardevHostdev *opts)
     CharDriverState *chr;
     WinCharState *s;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(WinCharState));
     chr->opaque = s;
     chr->chr_write = win_chr_write;
@@ -1981,7 +1987,7 @@ static CharDriverState *qemu_chr_open_win_file(HANDLE fd_out)
     CharDriverState *chr;
     WinCharState *s;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(WinCharState));
     s->hcom = fd_out;
     chr->opaque = s;
@@ -2137,7 +2143,7 @@ static CharDriverState *qemu_chr_open_stdio(ChardevStdio *opts)
     DWORD              dwMode;
     int                is_console = 0;
 
-    chr   = g_malloc0(sizeof(CharDriverState));
+    chr   = qemu_chr_alloc();
     stdio = g_malloc0(sizeof(WinStdioCharState));
 
     stdio->hStdIn = GetStdHandle(STD_INPUT_HANDLE);
@@ -2299,7 +2305,7 @@ static CharDriverState *qemu_chr_open_udp_fd(int fd)
     CharDriverState *chr = NULL;
     NetCharDriver *s = NULL;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(NetCharDriver));
 
     s->fd = fd;
@@ -2850,7 +2856,7 @@ static CharDriverState *qemu_chr_open_socket_fd(int fd, bool do_nodelay,
         return NULL;
     }
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(TCPCharDriver));
 
     s->connected = 0;
@@ -3040,7 +3046,7 @@ static CharDriverState *qemu_chr_open_ringbuf(ChardevRingbuf *opts,
     CharDriverState *chr;
     RingBufCharDriver *d;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     d = g_malloc(sizeof(*d));
 
     d->size = opts->has_size ? opts->size : 65536;

spice-qemu-char.c

@@ -268,7 +268,7 @@ static CharDriverState *chr_open(const char *subtype,
     CharDriverState *chr;
     SpiceCharDriver *s;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
     s = g_malloc0(sizeof(SpiceCharDriver));
     s->chr = chr;
     s->active = false;

ui/console.c

@@ -1821,7 +1821,7 @@ static CharDriverState *text_console_init(ChardevVC *vc)
     unsigned width = 0;
     unsigned height = 0;
 
-    chr = g_malloc0(sizeof(CharDriverState));
+    chr = qemu_chr_alloc();
 
     if (vc->has_width) {
         width = vc->width;