[Qemu-devel] [PATCH 2/5] Expose CirMemCharDriver via command line

[Lei Li <lilei@linux.vnet.ibm.com>]

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
---
 qemu-char.c     |   31 +++++++++++++++++++++++++++++++
 qemu-config.c   |    3 +++
 qemu-options.hx |   10 ++++++++++
 3 files changed, 44 insertions(+), 0 deletions(-)

diff --git a/qemu-char.c b/qemu-char.c
index 0470085..6e84acc 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -2675,6 +2675,31 @@ static void cirmem_chr_read(CharDriverState *chr, uint8_t *buf, int len)
     d->cbuf_count -= len;
 }
 
+static CharDriverState *qemu_chr_open_cirmemchr(QemuOpts *opts)
+{
+    CharDriverState *chr;
+    CircMemCharDriver *d;
+
+    chr = g_malloc0(sizeof(CharDriverState));
+    d = g_malloc(sizeof(*d));
+
+    d->cbuf_capacity = qemu_opt_get_number(opts, "maxcapacity", 0);
+    if (d->cbuf_capacity == 0) {
+        d->cbuf_capacity = CBUFF_SIZE;
+    }
+
+    d->cbuf_in = 0;
+    d->cbuf_out = 0;
+    d->cbuf_count = 0;
+    d->cbuf = g_malloc0(d->cbuf_capacity);
+
+    memset(chr, 0, sizeof(*chr));
+    chr->opaque = d;
+    chr->chr_write = mem_chr_write;
+
+    return chr;
+}
+
 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename)
 {
     char host[65], port[33], width[8], height[8];
@@ -2739,6 +2764,11 @@ QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename)
         qemu_opt_set(opts, "path", p);
         return opts;
     }
+    if (strstart(filename, "memchr", &p)) {
+        qemu_opt_set(opts, "backend", "memchr");
+        qemu_opt_set(opts, "maxcapacity", p);
+        return opts;
+    }
     if (strstart(filename, "tcp:", &p) ||
         strstart(filename, "telnet:", &p)) {
         if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
@@ -2812,6 +2842,7 @@ static const struct {
     { .name = "udp",       .open = qemu_chr_open_udp },
     { .name = "msmouse",   .open = qemu_chr_open_msmouse },
     { .name = "vc",        .open = text_console_init },
+    { .name = "memchr",    .open = qemu_chr_open_cirmemchr },
 #ifdef _WIN32
     { .name = "file",      .open = qemu_chr_open_win_file_out },
     { .name = "pipe",      .open = qemu_chr_open_win_pipe },
diff --git a/qemu-config.c b/qemu-config.c
index eba977e..5cb6dcb 100644
--- a/qemu-config.c
+++ b/qemu-config.c
@@ -213,6 +213,9 @@ static QemuOptsList qemu_chardev_opts = {
         },{
             .name = "debug",
             .type = QEMU_OPT_NUMBER,
+        },{
+            .name = "maxcapacity",
+            .type = QEMU_OPT_NUMBER,
         },
         { /* end of list */ }
     },
diff --git a/qemu-options.hx b/qemu-options.hx
index 804a2d1..3a7384d 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1666,6 +1666,7 @@ DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
     "-chardev msmouse,id=id[,mux=on|off]\n"
     "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
     "         [,mux=on|off]\n"
+    "-chardev memchr,id=id,maxcapacity=maxcapacity\n"
     "-chardev file,id=id,path=path[,mux=on|off]\n"
     "-chardev pipe,id=id,path=path[,mux=on|off]\n"
 #ifdef _WIN32
@@ -1704,6 +1705,7 @@ Backend is one of:
 @option{udp},
 @option{msmouse},
 @option{vc},
+@option{memchr},
 @option{file},
 @option{pipe},
 @option{console},
@@ -1810,6 +1812,14 @@ the console, in pixels.
 @option{cols} and @option{rows} specify that the console be sized to fit a text
 console with the given dimensions.
 
+@item -chardev memchr ,id=@var{id} ,maxcapacity=@var{maxcapacity}
+
+Create a circular buffer with fixed size indicated by optionally @option{maxcapacity}
+which will be default 64K if it is not given.
+
+@option{maxcapacity} specify the max capacity of the size of circular buffer
+want to create.
+
 @item -chardev file ,id=@var{id} ,path=@var{path}
 
 Log all traffic received from the guest to a file.
-- 
1.7.7.6