[Qemu-devel] [RFC][PATCH v5 19/21] virtagent: add virtagent guest daemon

[Michael Roth <mdroth@linux.vnet.ibm.com>]

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 Makefile  |    4 +-
 qemu-va.c |  327 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 330 insertions(+), 1 deletions(-)
 create mode 100644 qemu-va.c

diff --git a/Makefile b/Makefile
index 4e120a2..556c853 100644
--- a/Makefile
+++ b/Makefile
@@ -150,7 +150,7 @@ version-obj-$(CONFIG_WIN32) += version.o
 ######################################################################
 
 qemu-img.o: qemu-img-cmds.h
-qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o: $(GENERATED_HEADERS)
+qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o qemu-va.o: $(GENERATED_HEADERS)
 
 qemu-img$(EXESUF): qemu-img.o qemu-tool.o qemu-error.o $(oslib-obj-y) $(trace-obj-y) $(block-obj-y) $(qobject-obj-y) $(version-obj-y) qemu-timer-common.o
 
@@ -158,6 +158,8 @@ qemu-nbd$(EXESUF): qemu-nbd.o qemu-tool.o qemu-error.o $(oslib-obj-y) $(trace-ob
 
 qemu-io$(EXESUF): qemu-io.o cmd.o qemu-tool.o qemu-error.o $(oslib-obj-y) $(trace-obj-y) $(block-obj-y) $(qobject-obj-y) $(version-obj-y) qemu-timer-common.o
 
+qemu-va$(EXESUF): qemu-va.o virtagent.o virtagent-server.o virtagent-common.o qemu-tool.o qemu-error.o qemu-sockets.c $(oslib-obj-y) $(trace-obj-y) $(block-obj-y) $(qobject-obj-y) $(version-obj-y) qemu-timer-common.o
+
 qemu-img-cmds.h: $(SRC_PATH)/qemu-img-cmds.hx
 	$(call quiet-command,sh $(SRC_PATH)/hxtool -h < $< > $@,"  GEN   $@")
 
diff --git a/qemu-va.c b/qemu-va.c
new file mode 100644
index 0000000..1035b50
--- /dev/null
+++ b/qemu-va.c
@@ -0,0 +1,327 @@
+/*
+ * virtagent - QEMU guest agent
+ *
+ * Copyright IBM Corp. 2010
+ *
+ * Authors:
+ *  Michael Roth      <mdroth@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * 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.
+ */
+
+#include <getopt.h>
+#include <err.h>
+#include "qemu-option.h"
+#include "qemu_socket.h"
+#include "qemu-ioh.h"
+#include "virtagent-common.h"
+
+static bool verbose_enabled;
+#define DEBUG_ENABLED
+
+#ifdef DEBUG_ENABLED
+#define DEBUG(msg, ...) do { \
+    fprintf(stderr, "%s:%s():L%d: " msg "\n", \
+            __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
+} while(0)
+#else
+#define DEBUG(msg, ...) do {} while (0)
+#endif
+
+#define INFO(msg, ...) do { \
+    if (!verbose_enabled) { \
+        break; \
+    } \
+    warnx(msg, ## __VA_ARGS__); \
+} while(0)
+
+QemuOptsList va_opts = {
+    .name = "vaargs",
+    .head = QTAILQ_HEAD_INITIALIZER(va_opts.head),
+    .desc = {
+        {
+            .name = "channel_method",
+            .type = QEMU_OPT_STRING,
+        },{
+            .name = "path",
+            .type = QEMU_OPT_STRING,
+        },{
+            .name = "host",
+            .type = QEMU_OPT_STRING,
+        },{
+            .name = "port",
+            .type = QEMU_OPT_STRING,
+        },{
+            .name = "ipv4",
+            .type = QEMU_OPT_BOOL,
+        },{
+            .name = "ipv6",
+            .type = QEMU_OPT_BOOL,
+        },
+        { /* end of list */ }
+    },
+};
+
+/* parse channel options */
+static int va_parse(QemuOpts *opts, const char *str)
+{
+    char channel_method[32];
+    char *addr;
+    char port[33];
+    int pos, ret;
+
+    /* parse connection type */
+    ret = sscanf(str,"%32[^:]:%n",channel_method,&pos);
+    if (ret != 1) {
+        LOG("error parsing channel method");
+        return -EINVAL;
+    }
+    qemu_opt_set(opts, "channel_method", channel_method);
+    str += pos;
+    pos = 0;
+
+    /* parse path/addr and port */
+    if (str[0] == '[') {
+        /* ipv6 formatted */
+        ret = sscanf(str,"[%a[^]:]]:%32[^:]%n",&addr,port,&pos);
+        qemu_opt_set(opts, "ipv6", "on");
+    } else {
+        ret = sscanf(str,"%a[^:]:%32[^:]%n",&addr,port,&pos);
+        qemu_opt_set(opts, "ipv4", "on");
+    }
+
+    if (ret != 2) {
+        LOG("error parsing path/addr/port");
+        return -EINVAL;
+    } else if (port[0] == '-') {
+        /* no port given, assume unix path */
+        qemu_opt_set(opts, "path", addr);
+    } else {
+        qemu_opt_set(opts, "host", addr);
+        qemu_opt_set(opts, "port", port);
+        qemu_free(addr);
+    }
+    str += pos;
+    pos = 0;
+
+    return 0;
+}
+
+/* mirror qemu I/O loop for standalone daemon */
+static void main_loop_wait(int nonblocking)
+{
+    fd_set rfds, wfds, xfds;
+    int ret, nfds;
+    struct timeval tv;
+    int timeout = 100000;
+
+    if (nonblocking) {
+        timeout = 0;
+    }
+
+    /* poll any events */
+    nfds = -1;
+    FD_ZERO(&rfds);
+    FD_ZERO(&wfds);
+    FD_ZERO(&xfds);
+    qemu_get_fdset(&nfds, &rfds, &wfds, &xfds);
+
+    tv.tv_sec = timeout / 1000;
+    tv.tv_usec = (timeout % 1000) * 1000;
+
+    ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv);
+
+    if (ret > 0) {
+        qemu_process_fd_handlers(&rfds, &wfds, &xfds);
+    }
+}
+
+#define VP_ARG_LEN 256
+
+typedef struct VAData {
+    QemuOpts *opts;
+    void *opaque;
+    QTAILQ_ENTRY(VAData) next;
+} VAData;
+
+static QTAILQ_HEAD(, VAData) channels;
+
+static void usage(const char *cmd)
+{
+    printf(
+"Usage: %s -c <channel_opts>\n"
+"QEMU virtagent guest agent\n"
+"\n"
+"  -c, --channel     channel options of the form:\n"
+"                    <method>:<addr>:<port>[:channel_id]\n"
+"  -v, --verbose     display extra debugging information\n"
+"  -h, --help        display this help and exit\n"
+"\n"
+"  channels are used to establish a data connection between 2 end-points in\n"
+"  the host or the guest (connection method specified by <method>).\n"
+"  The positional parameters for channels are:\n"
+"\n"
+"  <method>:     one of unix-connect, unix-listen, tcp-connect, tcp-listen,\n"
+"                virtserial-open\n"
+"  <addr>:       path of unix socket or virtserial port, or IP of host, to\n"
+"                connect/bind to\n"
+"  <port>:       port to bind/connect to, or '-' if addr is a path\n"
+"\n"
+"Report bugs to <mdroth@linux.vnet.ibm.com>\n"
+    , cmd);
+}
+
+static int init_channels(void) {
+    VAData *channel_data;
+    const char *channel_method, *path;
+    int fd, ret;
+    bool listen;
+
+    if (QTAILQ_EMPTY(&channels)) {
+        warnx("no channel specified");
+        return -EINVAL;
+    }
+
+    channel_data = QTAILQ_FIRST(&channels);
+
+    /* TODO: add this support, optional idx param for -i/-o/-c
+     * args should suffice
+     */
+    if (QTAILQ_NEXT(channel_data, next) != NULL) {
+        warnx("multiple channels not currently supported, defaulting to first");
+    }
+
+    INFO("initializing channel...");
+    if (verbose_enabled) {
+        qemu_opts_print(channel_data->opts, NULL);
+    }
+
+    channel_method = qemu_opt_get(channel_data->opts, "channel_method");
+
+    if (strcmp(channel_method, "tcp-listen") == 0) {
+        fd = inet_listen_opts(channel_data->opts, 0);
+        listen = true;
+    } else if (strcmp(channel_method, "tcp-connect") == 0) {
+        fd = inet_connect_opts(channel_data->opts);
+        listen = false;
+    } else if (strcmp(channel_method, "unix-listen") == 0) {
+        fd = unix_listen_opts(channel_data->opts);
+        listen = true;
+    } else if (strcmp(channel_method, "unix-connect") == 0) {
+        fd = unix_connect_opts(channel_data->opts);
+        listen = false;
+    } else if (strcmp(channel_method, "virtio-serial") == 0) {
+        path = qemu_opt_get(channel_data->opts, "path");
+        fd = qemu_open(path, O_RDWR);
+        if (fd == -1) {
+            warn("error opening channel");
+            return errno;
+        }
+        ret = fcntl(fd, F_GETFL);
+        ret = fcntl(fd, F_SETFL, ret | O_ASYNC);
+        if (ret < 0) {
+            warn("error setting flags for fd");
+            return errno;
+        }
+        listen = false;
+    } else {
+        warnx("invalid channel type: %s", channel_method);
+        return -EINVAL;
+    }
+
+    if (fd == -1) {
+        warn("error opening connection");
+        return errno;
+    }
+
+    /* initialize virtagent */
+    ret = va_init(VA_CTX_GUEST, fd);
+    if (ret) {
+        errx(EXIT_FAILURE, "unable to initialize virtagent");
+    }
+
+
+    return 0;
+}
+
+int main(int argc, char **argv)
+{
+    const char *sopt = "hVvc:";
+    struct option lopt[] = {
+        { "help", 0, NULL, 'h' },
+        { "version", 0, NULL, 'V' },
+        { "verbose", 0, NULL, 'v' },
+        { "channel", 0, NULL, 'c' },
+        { NULL, 0, NULL, 0 }
+    };
+    int opt_ind = 0, ch, ret;
+    QTAILQ_INIT(&channels);
+
+    while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
+        QemuOpts *opts;
+        VAData *data;
+        switch (ch) {
+        case 'c':
+            opts = qemu_opts_create(&va_opts, NULL, 0);
+            ret = va_parse(opts, optarg);
+            if (ret) {
+                errx(EXIT_FAILURE, "error parsing arg: %s", optarg);
+            }
+            data = qemu_mallocz(sizeof(VAData));
+            data->opts = opts;
+            QTAILQ_INSERT_TAIL(&channels, data, next);
+            break;
+        case 'v':
+            verbose_enabled = 1;
+            break;
+        case 'h':
+            usage(argv[0]);
+            return 0;
+        case '?':
+            errx(EXIT_FAILURE, "Try '%s --help' for more information.",
+                 argv[0]);
+        }
+    }
+
+    /* initialize communication channel and pass it to virtagent */
+    /* XXX: we only support one channel now so this should be simplified */
+    ret = init_channels();
+    if (ret) {
+        errx(EXIT_FAILURE, "error initializing communication channel");
+    }
+
+    /* tell the host the agent is running */
+    va_send_hello();
+
+    /* main i/o loop */
+    for (;;) {
+        DEBUG("entering main_loop_wait()");
+        main_loop_wait(0);
+        DEBUG("left main_loop_wait()");
+    }
+
+    return 0;
+}
-- 
1.7.0.4