Currently screendump only supports PPM format, which is un-compressed and not standard. Added a "format" parameter to qemu monitor screendump capabilites to support PNG image capture using libpng. The param was added in QAPI schema of screendump present in ui.json along with png_save() function which converts pixman_image to PNG. HMP command equivalent was also modified to support the feature.
Example usage: { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } Resolves: https://gitlab.com/qemu-project/qemu/-/issues/718 Signed-off-by: Kshitij Suri <kshitij.s...@nutanix.com> --- hmp-commands.hx | 11 ++--- monitor/hmp-cmds.c | 8 +++- qapi/ui.json | 25 ++++++++++-- ui/console.c | 100 +++++++++++++++++++++++++++++++++++++++++++-- 4 files changed, 132 insertions(+), 12 deletions(-) diff --git a/hmp-commands.hx b/hmp-commands.hx index 70a9136ac2..e43c9954b5 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -244,17 +244,18 @@ ERST { .name = "screendump", - .args_type = "filename:F,device:s?,head:i?", - .params = "filename [device [head]]", - .help = "save screen from head 'head' of display device 'device' " - "into PPM image 'filename'", + .args_type = "filename:F,device:s?,head:i?,format:f?", + .params = "filename [device [head]] [format]", + .help = "save screen from head 'head' of display device 'device'" + "in specified format 'format' as image 'filename'." + "Currently only 'png' and 'ppm' formats are supported.", .cmd = hmp_screendump, .coroutine = true, }, SRST ``screendump`` *filename* - Save screen into PPM image *filename*. + Save screen as an image *filename*. ERST { diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c index 8c384dc1b2..c300545f34 100644 --- a/monitor/hmp-cmds.c +++ b/monitor/hmp-cmds.c @@ -1677,9 +1677,15 @@ hmp_screendump(Monitor *mon, const QDict *qdict) const char *filename = qdict_get_str(qdict, "filename"); const char *id = qdict_get_try_str(qdict, "device"); int64_t head = qdict_get_try_int(qdict, "head", 0); + const char *input_format = qdict_get_str(qdict, "format"); Error *err = NULL; + ImageFormat format = IMAGE_FORMAT_PPM; + if (input_format != NULL && strcmp(input_format, "png") == 0) { + format = IMAGE_FORMAT_PNG; + } - qmp_screendump(filename, id != NULL, id, id != NULL, head, &err); + qmp_screendump(filename, id != NULL, id, id != NULL, head, + input_format != NULL, format, &err); hmp_handle_error(mon, err); } diff --git a/qapi/ui.json b/qapi/ui.json index 9354f4c467..6aa0dd7c1b 100644 --- a/qapi/ui.json +++ b/qapi/ui.json @@ -73,12 +73,27 @@ ## { 'command': 'expire_password', 'data': {'protocol': 'str', 'time': 'str'} } +## +# @ImageFormat: +# +# Available list of supported types. +# +# @png: PNG format +# +# @ppm: PPM format +# +# Since: 7.0 +# +## +{ 'enum': 'ImageFormat', + 'data': ['ppm', 'png'] } + ## # @screendump: # -# Write a PPM of the VGA screen to a file. +# Write a screenshot of the VGA screen to a file. # -# @filename: the path of a new PPM file to store the image +# @filename: the path of a new file to store the image # # @device: ID of the display device that should be dumped. If this parameter # is missing, the primary display will be used. (Since 2.12) @@ -87,6 +102,9 @@ # parameter is missing, head #0 will be used. Also note that the head # can only be specified in conjunction with the device ID. (Since 2.12) # +# @format: image format for screendump is specified. ppm is the set as the +# default format. (Since 7.0) +# # Returns: Nothing on success # # Since: 0.14 @@ -99,7 +117,8 @@ # ## { 'command': 'screendump', - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', + '*format': 'ImageFormat'}, 'coroutine': true } ## diff --git a/ui/console.c b/ui/console.c index 40eebb6d2c..6180d293e6 100644 --- a/ui/console.c +++ b/ui/console.c @@ -37,6 +37,9 @@ #include "exec/memory.h" #include "io/channel-file.h" #include "qom/object.h" +#ifdef CONFIG_PNG +#include <png.h> +#endif #define DEFAULT_BACKSCROLL 512 #define CONSOLE_CURSOR_PERIOD 500 @@ -289,6 +292,87 @@ void graphic_hw_invalidate(QemuConsole *con) } } +#ifdef CONFIG_PNG +/** + * png_save: Take a screenshot as PNG + * + * Saves screendump as a PNG file + * + * Returns true for success or false for error. + * + * @fd: File descriptor for PNG file. + * @image: Image data in pixman format. + * @errp: Pointer to an error. + */ +static bool png_save(int fd, pixman_image_t *image, Error **errp) +{ + int width = pixman_image_get_width(image); + int height = pixman_image_get_height(image); + g_autofree png_struct *png_ptr = NULL; + g_autofree png_info *info_ptr = NULL; + g_autoptr(pixman_image_t) linebuf = + qemu_pixman_linebuf_create(PIXMAN_a8r8g8b8, width); + uint8_t *buf = (uint8_t *)pixman_image_get_data(linebuf); + FILE *f = fdopen(fd, "wb"); + int y; + if (!f) { + error_setg(errp, "Failed to create file from file descriptor"); + return false; + } + + png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, + NULL, NULL); + if (!png_ptr) { + error_setg(errp, "PNG creation failed. Unable to write struct"); + free(f); + return false; + } + + info_ptr = png_create_info_struct(png_ptr); + + if (!info_ptr) { + error_setg(errp, "PNG creation failed. Unable to write info"); + free(f); + png_destroy_write_struct(&png_ptr, &info_ptr); + return false; + } + + png_init_io(png_ptr, f); + + png_set_IHDR(png_ptr, info_ptr, width, height, 8, + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); + + png_write_info(png_ptr, info_ptr); + + for (y = 0; y < height; ++y) { + qemu_pixman_linebuf_fill(linebuf, image, width, 0, y); + png_write_row(png_ptr, buf); + } + qemu_pixman_image_unref(linebuf); + + png_write_end(png_ptr, NULL); + + png_destroy_write_struct(&png_ptr, &info_ptr); + + if (fclose(f) != 0) { + error_setg(errp, "PNG creation failed. Unable to close file"); + return false; + } + + return true; +} + +#else /* no png support */ + +static bool png_save(int fd, pixman_image_t *image, Error **errp) +{ + error_setg(errp, "Enable PNG support with libpng for screendump"); + return false; +} + +#endif /* CONFIG_PNG */ + static bool ppm_save(int fd, pixman_image_t *image, Error **errp) { int width = pixman_image_get_width(image); @@ -327,7 +411,8 @@ static void graphic_hw_update_bh(void *con) /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ void coroutine_fn qmp_screendump(const char *filename, bool has_device, const char *device, - bool has_head, int64_t head, Error **errp) + bool has_head, int64_t head, bool has_format, + ImageFormat format, Error **errp) { g_autoptr(pixman_image_t) image = NULL; QemuConsole *con; @@ -383,8 +468,17 @@ qmp_screendump(const char *filename, bool has_device, const char *device, * yields and releases the BQL. It could produce corrupted dump, but * it should be otherwise safe. */ - if (!ppm_save(fd, image, errp)) { - qemu_unlink(filename); + + if (has_format && format == IMAGE_FORMAT_PNG) { + /* PNG format specified for screendump */ + if (!png_save(fd, image, errp)) { + qemu_unlink(filename); + } + } else { + /* PPM format specified/default for screendump */ + if (!ppm_save(fd, image, errp)) { + qemu_unlink(filename); + } } } -- 2.22.3