[Qemu-devel] [PATCH 3/6] QAPI: Introduce memchar_write QMP command

[Lei Li]

Signed-off-by: Lei Li <address@hidden>
---
 hmp-commands.hx  |   16 ++++++++++++++++
 hmp.c            |   15 +++++++++++++++
 hmp.h            |    1 +
 qapi-schema.json |   28 ++++++++++++++++++++++++++++
 qemu-char.c      |   36 ++++++++++++++++++++++++++++++++++++
 qmp-commands.hx  |   33 +++++++++++++++++++++++++++++++++
 6 files changed, 129 insertions(+), 0 deletions(-)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index f6104b0..829aea1 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -797,6 +797,22 @@ Inject an NMI on the given CPU (x86 only).
 ETEXI
 
     {
+        .name       = "memchar-write",
+        .args_type  = "chardev:s,size:i,data:s,format:s?",
+        .params     = "chardev size data",
+        .help       = "Provide writing interface for memchardev. Write"
+                      "'data' to memchr char device with size 'size'",
+        .mhandler.cmd = hmp_memchar_write,
+    },
+
+STEXI
address@hidden memchar-write @var{chardev} @var{size} @var{data} @var{format}
address@hidden memchar-write
+Provide writing interface for memchardev. Write @var{data}
+to memchr char device with size @var{size}.
+ETEXI
+
+    {
         .name       = "migrate",
         .args_type  = "detach:-d,blk:-b,inc:-i,uri:s",
         .params     = "[-d] [-b] [-i] uri",
diff --git a/hmp.c b/hmp.c
index 81c8acb..c1164eb 100644
--- a/hmp.c
+++ b/hmp.c
@@ -668,6 +668,21 @@ void hmp_pmemsave(Monitor *mon, const QDict *qdict)
     hmp_handle_error(mon, &errp);
 }
 
+void hmp_memchar_write(Monitor *mon, const QDict *qdict)
+{
+    uint32_t size = qdict_get_int(qdict, "size");
+    const char *chardev = qdict_get_str(qdict, "chardev");
+    const char *data = qdict_get_str(qdict, "data");
+    int con = qdict_get_try_bool(qdict, "utf8", 0);
+    enum DataFormat format;
+    Error *errp = NULL;
+
+    format = con ? DATA_FORMAT_UTF8 : DATA_FORMAT_BASE64;
+    qmp_memchar_write(chardev, size, data, true, format, &errp);
+
+    hmp_handle_error(mon, &errp);
+}
+
 static void hmp_cont_cb(void *opaque, int err)
 {
     if (!err) {
diff --git a/hmp.h b/hmp.h
index 7dd93bf..15e1311 100644
--- a/hmp.h
+++ b/hmp.h
@@ -43,6 +43,7 @@ void hmp_system_powerdown(Monitor *mon, const QDict *qdict);
 void hmp_cpu(Monitor *mon, const QDict *qdict);
 void hmp_memsave(Monitor *mon, const QDict *qdict);
 void hmp_pmemsave(Monitor *mon, const QDict *qdict);
+void hmp_memchar_write(Monitor *mon, const QDict *qdict);
 void hmp_cont(Monitor *mon, const QDict *qdict);
 void hmp_system_wakeup(Monitor *mon, const QDict *qdict);
 void hmp_inject_nmi(Monitor *mon, const QDict *qdict);
diff --git a/qapi-schema.json b/qapi-schema.json
index bd8ad74..2fc1a27 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -235,6 +235,34 @@
 ##
 { 'command': 'query-chardev', 'returns': ['ChardevInfo'] }
 
+{ 'enum': 'DataFormat'
+  'data': [ 'utf8', 'base64' ] }
+
+##
+# @memchar-write:
+#
+# Provide writing interface for memchardev. Write data to memchar
+# char device.
+#
+# @chardev: the name of the memchar char device.
+#
+# @size: the size to write in bytes.
+#
+# @data: the source data write to memchar.
+#
+# @format: #optional the format of the data write to memchardev, by
+#          default is 'utf8'.
+#
+# Returns: Nothing on success
+#          If @chardev is not a valid memchr device, DeviceNotFound
+#          If an I/O error occurs while writing, IOError
+#
+# Since: 1.3
+##
+{ 'command': 'memchar-write',
+  'data': {'chardev': 'str', 'size': 'int', 'data': 'str',
+           '*format': 'DataFormat'} }
+
 ##
 # @CommandInfo:
 #
diff --git a/qemu-char.c b/qemu-char.c
index b21b93a..d8f3238 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -2647,6 +2647,42 @@ size_t qemu_chr_mem_osize(const CharDriverState *chr)
     return d->cbuf_count;
 }
 
+void qmp_memchar_write(const char *chardev, int64_t size,
+                       const char *data, bool has_format,
+                       enum DataFormat format,
+
+                       Error **errp)
+{
+    CharDriverState *chr;
+    guchar *write_data;
+    int ret;
+    gsize write_count;
+
+    chr = qemu_chr_find(chardev);
+
+    if(!chr) {
+        error_set(errp, QERR_DEVICE_NOT_FOUND, chardev);
+        return;
+    }
+
+    write_count = (gsize)size;
+
+    if (has_format) {
+        if (format == DATA_FORMAT_BASE64) {
+            write_data = g_base64_decode(data, &write_count);
+        }
+    } else {
+        write_data = (uint8_t *)data;
+    }
+
+    ret = mem_chr_write(chr, write_data, size);
+    if (ret <= 0) {
+        error_set(errp, QERR_IO_ERROR);
+    }
+    g_free(write_data);
+
+}
+
 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename)
 {
     char host[65], port[33], width[8], height[8];
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 3745a21..3c747cd 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -441,6 +441,39 @@ Note: inject-nmi fails when the guest doesn't support 
injecting.
 EQMP
 
     {
+        .name       = "memchar-write",
+        .args_type  = "chardev:s,size:i,data:s,format:s?",
+        .mhandler.cmd_new = qmp_marshal_input_memchar_write,
+    },
+
+SQMP
+memchar-write
+-------------
+
+Provide writing interface for memchardev. Write data to memchar
+char device.
+
+Arguments:
+
+- "chardev": the name of the char device, must be unique (json-string)
+- "size": the memory size, in bytes (json-int)
+- "data": the source data writed to memchar (json-string)
+- "format": the data format write to memchardev
+  (DataFormat, optional, support "utf8" and "base64" now, default "utf8")
+
+
+Example:
+
+-> { "execute": "memchar-write",
+                "arguments": { "chardev": foo,
+                               "size": 1000,
+                               "data": "data string...",
+                               "format": "utf8" } }
+<- { "return": {} }
+
+EQMP
+
+    {
         .name       = "xen-save-devices-state",
         .args_type  = "filename:F",
     .mhandler.cmd_new = qmp_marshal_input_xen_save_devices_state,
-- 
1.7.7.6