[Qemu-devel] [PATCH 3/4] qxl: add debug_cs and cmdlog_cs

[Alon Levy <alevy@redhat.com>]

With this you can output the command log and/or the guest debug (driver)
output to a chardev instead of stderr:

-global qxl-vga.cmdlog_chardev=qxl_cmdlog_chardev
-global qxl-vga.debug_chardev=qxl_debug_chardev

useful for debugging. if no chardev is specified prints to stderr like the old
code.
---
 hw/qxl-logger.c |   62 ++++++++++++++++++++++++++++++++++--------------------
 hw/qxl.c        |   14 +++++++++++-
 hw/qxl.h        |    2 +
 3 files changed, 54 insertions(+), 24 deletions(-)

diff --git a/hw/qxl-logger.c b/hw/qxl-logger.c
index 76f43e6..df6e78b 100644
--- a/hw/qxl-logger.c
+++ b/hw/qxl-logger.c
@@ -99,6 +99,22 @@ static const char *qxl_v2n(const char *n[], size_t l, int v)
 }
 #define qxl_name(_list, _value) qxl_v2n(_list, ARRAY_SIZE(_list), _value)
 
+static void qxl_log_printf(PCIQXLDevice *qxl, const char *format, ...)
+{
+    va_list ap;
+    uint8_t buf[4096];
+
+    va_start(ap, format);
+    if (qxl->cmdlog_cs) {
+        vsnprintf((char *)buf, sizeof(buf), format, ap);
+        buf[sizeof(buf) - 1] = '\0';
+        qemu_chr_write(qxl->cmdlog_cs, buf, strlen((char*)buf));
+    } else {
+        vfprintf(stderr, format, ap);
+    }
+    va_end(ap);
+}
+
 static void qxl_log_image(PCIQXLDevice *qxl, QXLPHYSICAL addr, int group_id)
 {
     QXLImage *image;
@@ -106,11 +122,11 @@ static void qxl_log_image(PCIQXLDevice *qxl, QXLPHYSICAL addr, int group_id)
 
     image = qxl_phys2virt(qxl, addr, group_id);
     desc = &image->descriptor;
-    fprintf(stderr, " (id %" PRIx64 " type %d flags %d width %d height %d",
+    qxl_log_printf(qxl, " (id %" PRIx64 " type %d flags %d width %d height %d",
             desc->id, desc->type, desc->flags, desc->width, desc->height);
     switch (desc->type) {
     case SPICE_IMAGE_TYPE_BITMAP:
-        fprintf(stderr, ", fmt %d flags %d x %d y %d stride %d"
+        qxl_log_printf(qxl, ", fmt %d flags %d x %d y %d stride %d"
                 " palette %" PRIx64 " data %" PRIx64,
                 image->bitmap.format, image->bitmap.flags,
                 image->bitmap.x, image->bitmap.y,
@@ -118,12 +134,12 @@ static void qxl_log_image(PCIQXLDevice *qxl, QXLPHYSICAL addr, int group_id)
                 image->bitmap.palette, image->bitmap.data);
         break;
     }
-    fprintf(stderr, ")");
+    qxl_log_printf(qxl, ")");
 }
 
-static void qxl_log_rect(QXLRect *rect)
+static void qxl_log_rect(PCIQXLDevice *qxl, QXLRect *rect)
 {
-    fprintf(stderr, " %dx%d+%d+%d",
+    qxl_log_printf(qxl, " %dx%d+%d+%d",
             rect->right - rect->left,
             rect->bottom - rect->top,
             rect->left, rect->top);
@@ -131,17 +147,17 @@ static void qxl_log_rect(QXLRect *rect)
 
 static void qxl_log_cmd_draw_copy(PCIQXLDevice *qxl, QXLCopy *copy, int group_id)
 {
-    fprintf(stderr, " src %" PRIx64,
+    qxl_log_printf(qxl, " src %" PRIx64,
             copy->src_bitmap);
     qxl_log_image(qxl, copy->src_bitmap, group_id);
-    fprintf(stderr, " area");
-    qxl_log_rect(&copy->src_area);
-    fprintf(stderr, " rop %d", copy->rop_descriptor);
+    qxl_log_printf(qxl, " area");
+    qxl_log_rect(qxl, &copy->src_area);
+    qxl_log_printf(qxl, " rop %d", copy->rop_descriptor);
 }
 
 static void qxl_log_cmd_draw(PCIQXLDevice *qxl, QXLDrawable *draw, int group_id)
 {
-    fprintf(stderr, ": surface_id %d type %s effect %s",
+    qxl_log_printf(qxl, ": surface_id %d type %s effect %s",
             draw->surface_id,
             qxl_name(qxl_draw_type, draw->type),
             qxl_name(qxl_draw_effect, draw->effect));
@@ -155,13 +171,13 @@ static void qxl_log_cmd_draw(PCIQXLDevice *qxl, QXLDrawable *draw, int group_id)
 static void qxl_log_cmd_draw_compat(PCIQXLDevice *qxl, QXLCompatDrawable *draw,
                                     int group_id)
 {
-    fprintf(stderr, ": type %s effect %s",
+    qxl_log_printf(qxl, ": type %s effect %s",
             qxl_name(qxl_draw_type, draw->type),
             qxl_name(qxl_draw_effect, draw->effect));
     if (draw->bitmap_offset) {
-        fprintf(stderr, ": bitmap %d",
+        qxl_log_printf(qxl, ": bitmap %d",
                 draw->bitmap_offset);
-        qxl_log_rect(&draw->bitmap_area);
+        qxl_log_rect(qxl, &draw->bitmap_area);
     }
     switch (draw->type) {
     case QXL_DRAW_COPY:
@@ -172,11 +188,11 @@ static void qxl_log_cmd_draw_compat(PCIQXLDevice *qxl, QXLCompatDrawable *draw,
 
 static void qxl_log_cmd_surface(PCIQXLDevice *qxl, QXLSurfaceCmd *cmd)
 {
-    fprintf(stderr, ": %s id %d",
+    qxl_log_printf(qxl, ": %s id %d",
             qxl_name(qxl_surface_cmd, cmd->type),
             cmd->surface_id);
     if (cmd->type == QXL_SURFACE_CMD_CREATE) {
-        fprintf(stderr, " size %dx%d stride %d format %s (count %d, max %d)",
+        qxl_log_printf(qxl, " size %dx%d stride %d format %s (count %d, max %d)",
                 cmd->u.surface_create.width,
                 cmd->u.surface_create.height,
                 cmd->u.surface_create.stride,
@@ -184,7 +200,7 @@ static void qxl_log_cmd_surface(PCIQXLDevice *qxl, QXLSurfaceCmd *cmd)
                 qxl->guest_surfaces.count, qxl->guest_surfaces.max);
     }
     if (cmd->type == QXL_SURFACE_CMD_DESTROY) {
-        fprintf(stderr, " (count %d)", qxl->guest_surfaces.count);
+        qxl_log_printf(qxl, " (count %d)", qxl->guest_surfaces.count);
     }
 }
 
@@ -192,17 +208,17 @@ void qxl_log_cmd_cursor(PCIQXLDevice *qxl, QXLCursorCmd *cmd, int group_id)
 {
     QXLCursor *cursor;
 
-    fprintf(stderr, ": %s",
+    qxl_log_printf(qxl, ": %s",
             qxl_name(qxl_cursor_cmd, cmd->type));
     switch (cmd->type) {
     case QXL_CURSOR_SET:
-        fprintf(stderr, " +%d+%d visible %s, shape @ 0x%" PRIx64,
+        qxl_log_printf(qxl, " +%d+%d visible %s, shape @ 0x%" PRIx64,
                 cmd->u.set.position.x,
                 cmd->u.set.position.y,
                 cmd->u.set.visible ? "yes" : "no",
                 cmd->u.set.shape);
         cursor = qxl_phys2virt(qxl, cmd->u.set.shape, group_id);
-        fprintf(stderr, " type %s size %dx%d hot-spot +%d+%d"
+        qxl_log_printf(qxl, " type %s size %dx%d hot-spot +%d+%d"
                 " unique 0x%" PRIx64 " data-size %d",
                 qxl_name(spice_cursor_type, cursor->header.type),
                 cursor->header.width, cursor->header.height,
@@ -210,7 +226,7 @@ void qxl_log_cmd_cursor(PCIQXLDevice *qxl, QXLCursorCmd *cmd, int group_id)
                 cursor->header.unique, cursor->data_size);
         break;
     case QXL_CURSOR_MOVE:
-        fprintf(stderr, " +%d+%d", cmd->u.position.x, cmd->u.position.y);
+        qxl_log_printf(qxl, " +%d+%d", cmd->u.position.x, cmd->u.position.y);
         break;
     }
 }
@@ -223,8 +239,8 @@ void qxl_log_command(PCIQXLDevice *qxl, const char *ring, QXLCommandExt *ext)
     if (!qxl->cmdlog) {
         return;
     }
-    fprintf(stderr, "qxl-%d/%s:", qxl->id, ring);
-    fprintf(stderr, " cmd @ 0x%" PRIx64 " %s%s", ext->cmd.data,
+    qxl_log_printf(qxl, "qxl-%d/%s:", qxl->id, ring);
+    qxl_log_printf(qxl, " cmd @ 0x%" PRIx64 " %s%s", ext->cmd.data,
             qxl_name(qxl_type, ext->cmd.type),
             compat ? "(compat)" : "");
 
@@ -244,5 +260,5 @@ void qxl_log_command(PCIQXLDevice *qxl, const char *ring, QXLCommandExt *ext)
         qxl_log_cmd_cursor(qxl, data, ext->group_id);
         break;
     }
-    fprintf(stderr, "\n");
+    qxl_log_printf(qxl, "\n");
 }
diff --git a/hw/qxl.c b/hw/qxl.c
index ccd820c..86b98ee 100644
--- a/hw/qxl.c
+++ b/hw/qxl.c
@@ -933,6 +933,7 @@ static void ioport_write(void *opaque, uint32_t addr, uint32_t val)
 {
     PCIQXLDevice *d = opaque;
     uint32_t io_port = addr - d->io_base;
+    uint8_t guest_debug_cs_buf[QXL_LOG_BUF_SIZE];
 
     switch (io_port) {
     case QXL_IO_RESET:
@@ -984,8 +985,15 @@ static void ioport_write(void *opaque, uint32_t addr, uint32_t val)
         qxl_set_mode(d, val, 0);
         break;
     case QXL_IO_LOG:
+        d->ram->log_buf[QXL_LOG_BUF_SIZE - 1] = '\0';
         if (d->guestdebug) {
-            fprintf(stderr, "qxl/guest: %s", d->ram->log_buf);
+            if (d->debug_cs) {
+                snprintf((char*)guest_debug_cs_buf, QXL_LOG_BUF_SIZE, "%ld %s",
+                         qemu_get_clock(vm_clock), d->ram->log_buf);
+                qemu_chr_write(d->debug_cs, guest_debug_cs_buf, strlen((char*)guest_debug_cs_buf));
+            } else {
+                fprintf(stderr, "qxl/guest: %s", d->ram->log_buf);
+            }
         }
         break;
     case QXL_IO_RESET:
@@ -1514,6 +1522,8 @@ static PCIDeviceInfo qxl_info_primary = {
         DEFINE_PROP_UINT32("debug", PCIQXLDevice, debug, 0),
         DEFINE_PROP_UINT32("guestdebug", PCIQXLDevice, guestdebug, 0),
         DEFINE_PROP_UINT32("cmdlog", PCIQXLDevice, cmdlog, 0),
+        DEFINE_PROP_CHR("debug_chardev", PCIQXLDevice, debug_cs),
+        DEFINE_PROP_CHR("cmdlog_chardev", PCIQXLDevice, cmdlog_cs),
         DEFINE_PROP_END_OF_LIST(),
     }
 };
@@ -1532,6 +1542,8 @@ static PCIDeviceInfo qxl_info_secondary = {
         DEFINE_PROP_UINT32("debug", PCIQXLDevice, debug, 0),
         DEFINE_PROP_UINT32("guestdebug", PCIQXLDevice, guestdebug, 0),
         DEFINE_PROP_UINT32("cmdlog", PCIQXLDevice, cmdlog, 0),
+        DEFINE_PROP_CHR("debug_chardev", PCIQXLDevice, debug_cs),
+        DEFINE_PROP_CHR("cmdlog_chardev", PCIQXLDevice, cmdlog_cs),
         DEFINE_PROP_END_OF_LIST(),
     }
 };
diff --git a/hw/qxl.h b/hw/qxl.h
index f6c450d..2384c4e 100644
--- a/hw/qxl.h
+++ b/hw/qxl.h
@@ -22,6 +22,8 @@ typedef struct PCIQXLDevice {
     uint32_t           debug;
     uint32_t           guestdebug;
     uint32_t           cmdlog;
+    CharDriverState   *debug_cs;
+    CharDriverState   *cmdlog_cs;
     enum qxl_mode      mode;
     uint32_t           cmdflags;
     int                generation;
-- 
1.7.4.2