On Fri, Feb 25, 2022 at 11:58:30AM +0000, Kshitij Suri wrote: > 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> > ---
> + .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*. Maybe: as an image *filename*, with default format of PPM. > 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; > + } Instead of open-coding the string-to-enum translation (which will be hard to located if we expand to a third format down the road), you should use qapi_enum_parse(&ImageFormat_lookup, ...). > +++ 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"); error_setg_errno() might be nicer to use here, since fdopen() failure sets errno. > + return false; > + } > + > + png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, > + NULL, NULL); Indentation looks off. > + if (!png_ptr) { > + error_setg(errp, "PNG creation failed. Unable to write struct"); > + free(f); free() is the wrong function to call on FILE*. You meant fclose(). > + 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); and again > + 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"); Another spot for error_setg_errno -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org