[Qemu-devel] [PATCH v2] create qemu_openpty_raw() helper function and move it to a separate file

[Michael Tokarev]

In two places qemu uses openpty() which is very system-dependent,
and in both places the pty is switched to raw mode as well.
Make a wrapper function which does both steps, and move all the
system-dependent complexity into a separate file, together
with static/local implementations of openpty() and cfmakeraw()
from qemu-char.c.

It is in a separate file, not part of oslib-posix.c, because
openpty() often resides in -lutil which is not linked to
every program qemu builds.

This change removes #including of <pty.h>, <termios.h>
and other rather specific system headers out of qemu-common.h,
which isn't a place for such specific headers really.

Signed-off-by: Michael Tokarev <address@hidden>
---
Changes since v1:

- added a forgotten #include <termios.h> for *BSD,
  which was recently added into qemu-common.h by
  Brad Smith, and which I intended to use in
  qemu-openpty.c too, but somehow forgot.

And one extra comment.  I especially took existing
code and used it almost unmodified, to have one
code moving change, with all other possible
improvements/cleanups to follow later.

 include/qemu-common.h |   15 +-----
 qemu-char.c           |   77 ++--------------------------
 ui/gtk.c              |   12 ++---
 util/Makefile.objs    |    2 +-
 util/qemu-openpty.c   |  135 +++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 146 insertions(+), 95 deletions(-)
 create mode 100644 util/qemu-openpty.c

diff --git a/include/qemu-common.h b/include/qemu-common.h
index cb82ef3..3b1ca8e 100644
--- a/include/qemu-common.h
+++ b/include/qemu-common.h
@@ -42,19 +42,6 @@
 #include <signal.h>
 #include "glib-compat.h"
 
-#if defined(__GLIBC__)
-# include <pty.h>
-#elif defined CONFIG_BSD
-# include <termios.h>
-# if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || 
defined(__DragonFly__)
-#  include <libutil.h>
-# else
-#  include <util.h>
-# endif
-#elif defined CONFIG_SOLARIS
-# include <stropts.h>
-#endif
-
 #ifdef _WIN32
 #include "sysemu/os-win32.h"
 #endif
@@ -232,6 +219,8 @@ ssize_t qemu_recv_full(int fd, void *buf, size_t count, int 
flags)
 
 #ifndef _WIN32
 int qemu_pipe(int pipefd[2]);
+/* like openpty() but also makes it raw; return master fd */
+int qemu_openpty_raw(int *aslave, char *pty_name);
 #endif
 
 #ifdef _WIN32
diff --git a/qemu-char.c b/qemu-char.c
index d04b429..3759eff 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -980,63 +980,6 @@ static CharDriverState *qemu_chr_open_stdio(ChardevStdio 
*opts)
     return chr;
 }
 
-#ifdef __sun__
-/* Once Solaris has openpty(), this is going to be removed. */
-static int openpty(int *amaster, int *aslave, char *name,
-                   struct termios *termp, struct winsize *winp)
-{
-        const char *slave;
-        int mfd = -1, sfd = -1;
-
-        *amaster = *aslave = -1;
-
-        mfd = open("/dev/ptmx", O_RDWR | O_NOCTTY);
-        if (mfd < 0)
-                goto err;
-
-        if (grantpt(mfd) == -1 || unlockpt(mfd) == -1)
-                goto err;
-
-        if ((slave = ptsname(mfd)) == NULL)
-                goto err;
-
-        if ((sfd = open(slave, O_RDONLY | O_NOCTTY)) == -1)
-                goto err;
-
-        if (ioctl(sfd, I_PUSH, "ptem") == -1 ||
-            (termp != NULL && tcgetattr(sfd, termp) < 0))
-                goto err;
-
-        if (amaster)
-                *amaster = mfd;
-        if (aslave)
-                *aslave = sfd;
-        if (winp)
-                ioctl(sfd, TIOCSWINSZ, winp);
-
-        return 0;
-
-err:
-        if (sfd != -1)
-                close(sfd);
-        close(mfd);
-        return -1;
-}
-
-static void cfmakeraw (struct termios *termios_p)
-{
-        termios_p->c_iflag &=
-                ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON);
-        termios_p->c_oflag &= ~OPOST;
-        termios_p->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
-        termios_p->c_cflag &= ~(CSIZE|PARENB);
-        termios_p->c_cflag |= CS8;
-
-        termios_p->c_cc[VMIN] = 0;
-        termios_p->c_cc[VTIME] = 0;
-}
-#endif
-
 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
     || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
     || defined(__GLIBC__)
@@ -1208,34 +1151,24 @@ static CharDriverState *qemu_chr_open_pty(const char 
*id,
 {
     CharDriverState *chr;
     PtyCharDriver *s;
-    struct termios tty;
     int master_fd, slave_fd;
-#if defined(__OpenBSD__) || defined(__DragonFly__)
     char pty_name[PATH_MAX];
-#define q_ptsname(x) pty_name
-#else
-    char *pty_name = NULL;
-#define q_ptsname(x) ptsname(x)
-#endif
 
-    if (openpty(&master_fd, &slave_fd, pty_name, NULL, NULL) < 0) {
+    master_fd = qemu_openpty_raw(&slave_fd, pty_name);
+    if (master_fd < 0) {
         return NULL;
     }
 
-    /* Set raw attributes on the pty. */
-    tcgetattr(slave_fd, &tty);
-    cfmakeraw(&tty);
-    tcsetattr(slave_fd, TCSAFLUSH, &tty);
     close(slave_fd);
 
     chr = g_malloc0(sizeof(CharDriverState));
 
-    chr->filename = g_strdup_printf("pty:%s", q_ptsname(master_fd));
-    ret->pty = g_strdup(q_ptsname(master_fd));
+    chr->filename = g_strdup_printf("pty:%s", pty_name);
+    ret->pty = g_strdup(pty_name);
     ret->has_pty = true;
 
     fprintf(stderr, "char device redirected to %s (label %s)\n",
-            q_ptsname(master_fd), id);
+            pty_name, id);
 
     s = g_malloc0(sizeof(PtyCharDriver));
     chr->opaque = s;
diff --git a/ui/gtk.c b/ui/gtk.c
index 52c3f95..3405df6 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -1156,8 +1156,7 @@ static GSList *gd_vc_init(GtkDisplayState *s, 
VirtualConsole *vc, int index, GSL
     GIOChannel *chan;
     GtkWidget *scrolled_window;
     GtkAdjustment *vadjustment;
-    int master_fd, slave_fd, ret;
-    struct termios tty;
+    int master_fd, slave_fd;
 
     snprintf(buffer, sizeof(buffer), "vc%d", index);
     snprintf(path, sizeof(path), "<QEMU>/View/VC%d", index);
@@ -1177,13 +1176,8 @@ static GSList *gd_vc_init(GtkDisplayState *s, 
VirtualConsole *vc, int index, GSL
 
     vc->terminal = vte_terminal_new();
 
-    ret = openpty(&master_fd, &slave_fd, NULL, NULL, NULL);
-    g_assert(ret != -1);
-
-    /* Set raw attributes on the pty. */
-    tcgetattr(slave_fd, &tty);
-    cfmakeraw(&tty);
-    tcsetattr(slave_fd, TCSAFLUSH, &tty);
+    master_fd = qemu_openpty_raw(&slave_fd, NULL);
+    g_assert(master_fd != -1);
 
 #if VTE_CHECK_VERSION(0, 26, 0)
     pty = vte_pty_new_foreign(master_fd, NULL);
diff --git a/util/Makefile.objs b/util/Makefile.objs
index 4a1bd4e..dc72ab0 100644
--- a/util/Makefile.objs
+++ b/util/Makefile.objs
@@ -1,6 +1,6 @@
 util-obj-y = osdep.o cutils.o unicode.o qemu-timer-common.o
 util-obj-$(CONFIG_WIN32) += oslib-win32.o qemu-thread-win32.o 
event_notifier-win32.o
-util-obj-$(CONFIG_POSIX) += oslib-posix.o qemu-thread-posix.o 
event_notifier-posix.o
+util-obj-$(CONFIG_POSIX) += oslib-posix.o qemu-thread-posix.o 
event_notifier-posix.o qemu-openpty.o
 util-obj-y += envlist.o path.o host-utils.o cache-utils.o module.o
 util-obj-y += bitmap.o bitops.o hbitmap.o
 util-obj-y += fifo8.o
diff --git a/util/qemu-openpty.c b/util/qemu-openpty.c
new file mode 100644
index 0000000..6d7bd4b
--- /dev/null
+++ b/util/qemu-openpty.c
@@ -0,0 +1,135 @@
+/*
+ * qemu-openpty.c
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ * Copyright (c) 2010 Red Hat, Inc.
+ *
+ * Wrapper function qemu_openpty() implementation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to 
deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+/*
+ * This is not part of oslib-posix.c because this function
+ * uses openpty() which often in -lutil, and if we add this
+ * dependency to oslib-posix.o, every app will have to be
+ * linked with -lutil.
+ */
+
+#include "config-host.h"
+#include "qemu-common.h"
+
+#if defined(__GLIBC__)
+# include <pty.h>
+#elif defined CONFIG_BSD
+# include <termios.h>
+# if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || 
defined(__DragonFly__)
+#  include <libutil.h>
+# else
+#  include <util.h>
+# endif
+#elif defined CONFIG_SOLARIS
+# include <stropts.h>
+#endif
+
+#ifdef __sun__
+/* Once Solaris has openpty(), this is going to be removed. */
+static int openpty(int *amaster, int *aslave, char *name,
+                   struct termios *termp, struct winsize *winp)
+{
+        const char *slave;
+        int mfd = -1, sfd = -1;
+
+        *amaster = *aslave = -1;
+
+        mfd = open("/dev/ptmx", O_RDWR | O_NOCTTY);
+        if (mfd < 0)
+                goto err;
+
+        if (grantpt(mfd) == -1 || unlockpt(mfd) == -1)
+                goto err;
+
+        if ((slave = ptsname(mfd)) == NULL)
+                goto err;
+
+        if ((sfd = open(slave, O_RDONLY | O_NOCTTY)) == -1)
+                goto err;
+
+        if (ioctl(sfd, I_PUSH, "ptem") == -1 ||
+            (termp != NULL && tcgetattr(sfd, termp) < 0))
+                goto err;
+
+        if (amaster)
+                *amaster = mfd;
+        if (aslave)
+                *aslave = sfd;
+        if (winp)
+                ioctl(sfd, TIOCSWINSZ, winp);
+
+        return 0;
+
+err:
+        if (sfd != -1)
+                close(sfd);
+        close(mfd);
+        return -1;
+}
+
+static void cfmakeraw (struct termios *termios_p)
+{
+        termios_p->c_iflag &=
+                ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON);
+        termios_p->c_oflag &= ~OPOST;
+        termios_p->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
+        termios_p->c_cflag &= ~(CSIZE|PARENB);
+        termios_p->c_cflag |= CS8;
+
+        termios_p->c_cc[VMIN] = 0;
+        termios_p->c_cc[VTIME] = 0;
+}
+#endif
+
+int qemu_openpty_raw(int *aslave, char *pty_name)
+{
+    int amaster;
+    struct termios tty;
+#if defined(__OpenBSD__) || defined(__DragonFly__)
+    char pty_buf[PATH_MAX];
+#define q_ptsname(x) pty_buf
+#else
+    char *pty_buf = NULL;
+#define q_ptsname(x) ptsname(x)
+#endif
+
+    if (openpty(&amaster, aslave, pty_buf, NULL, NULL) < 0) {
+        return -1;
+    }
+
+    /* Set raw attributes on the pty. */
+    tcgetattr(*aslave, &tty);
+    cfmakeraw(&tty);
+    tcsetattr(*aslave, TCSAFLUSH, &tty);
+
+    if (pty_name) {
+        strcpy(pty_name, q_ptsname(amaster));
+    }
+
+    return amaster;
+}
+
-- 
1.7.10.4