[libvirt] [PATCH v2] screenshot: Expose the new API in virsh

* tools/virsh.c: Add screenshot command * tools/virsh.pod: Document new command * src/libvirt.c: Fix off-be-one error --- diff to v1: - make filename optional and generate filename when missing src/libvirt.c | 2 +- tools/virsh.c | 152 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ tools/virsh.pod | 9 +++ 3 files changed, 162 insertions(+), 1 deletions(-) diff --git a/src/libvirt.c b/src/libvirt.c index 5a5439d..cfb9e3b 100644 --- a/src/libvirt.c +++ b/src/libvirt.c @@ -2461,7 +2461,7 @@ error: * The screen ID is the sequential number of screen. In case of multiple * graphics cards, heads are enumerated before devices, e.g. having * two graphics cards, both with four heads, screen ID 5 addresses - * the first head on the second card. + * the second head on the second card. * * Returns a string representing the mime-type of the image format, or * NULL upon error. The caller must free() the returned value. diff --git a/tools/virsh.c b/tools/virsh.c index e35637d..aad930e 100644 --- a/tools/virsh.c +++ b/tools/virsh.c @@ -1879,6 +1879,157 @@ cmdDump(vshControl *ctl, const vshCmd *cmd) return ret; } +static const vshCmdInfo info_screenshot[] = { + {"help", N_("take a screenshot of a current domain console and store it " + "into a file")}, + {"desc", N_("screenshot of a current domain console")}, + {NULL, NULL} +}; + +static const vshCmdOptDef opts_screenshot[] = { + {"domain", VSH_OT_DATA, VSH_OFLAG_REQ, N_("domain name, id or uuid")}, + {"file", VSH_OT_DATA, VSH_OFLAG_NONE, N_("where to store the screenshot")}, + {"screen", VSH_OT_INT, VSH_OFLAG_NONE, N_("ID of a screen to take screenshot of")}, + {NULL, 0, 0, NULL} +}; + +static int cmdScreenshotSink(virStreamPtr st ATTRIBUTE_UNUSED, + const char *bytes, size_t nbytes, void *opaque) +{ + int *fd = opaque; + + return safewrite(*fd, bytes, nbytes); +} + +/** + * Generate string: '<domain name>-<timestamp>>[<extension>]' + */ +static char * +vshGenerFileName(vshControl *ctl, virDomainPtr dom) { + char timestr[100]; + struct timeval cur_time; + struct tm time_info; + const char *ext = NULL; + const char *hypType = NULL; + char *ret = NULL; + + /* We should be already connected, but doesn't + * hurt to check */ + if (!vshConnectionUsability(ctl, ctl->conn)) + return NULL; + + if (!dom) { + vshError(ctl, "%s", _("Invalid domain supplied")); + return NULL; + } + + if (!(hypType = virConnectGetType(ctl->conn))) { + vshError(ctl, "%s", _("Can't query hypervisor's type")); + return NULL; + } + + if (STREQ(hypType, "QEMU")) + ext = ".ppm"; + else if (STREQ(hypType, "VBOX")) + ext = ".png"; + /* add hypervisors here */ + + gettimeofday(&cur_time, NULL); + localtime_r(&cur_time.tv_sec, &time_info); + strftime(timestr, sizeof(timestr), "%Y-%m-%d-%H:%M:%S", &time_info); + + if (virAsprintf(&ret, "%s-%s%s", virDomainGetName(dom), + timestr, ext ? ext : "") < 0) { + vshError(ctl, "%s", _("Out of memory")); + return false; + } + + return ret; +} + +static bool +cmdScreenshot(vshControl *ctl, const vshCmd *cmd) { + virDomainPtr dom; + const char *name = NULL; + char *file = NULL; + int fd = -1; + virStreamPtr st = NULL; + unsigned int screen = 0; + unsigned int flags = 0; /* currently unused */ + int ret = false; + bool created = true; + bool generated = false; + char *mime = NULL; + + if (!vshConnectionUsability(ctl, ctl->conn)) + return false; + + if (vshCommandOptString(cmd, "file", (const char **) &file) < 0) { + vshError(ctl, "%s", _("file must not be empty")); + return false; + } + + if (vshCommandOptInt(cmd, "screen", (int*) &screen) < 0) { + vshError(ctl, "%s", _("invalid screen ID")); + return false; + } + + if (!(dom = vshCommandOptDomain(ctl, cmd, &name))) + return false; + + if (!file) { + if (!(file=vshGenerFileName(ctl, dom))) + return false; + generated = true; + } + + if ((fd = open(file, O_WRONLY|O_CREAT|O_EXCL, 0666)) < 0) { + created = false; + if (errno != EEXIST || + (fd = open(file, O_WRONLY|O_TRUNC, 0666)) < 0) { + vshError(ctl, _("cannot create file %s"), file); + goto cleanup; + } + } + + st = virStreamNew(ctl->conn, 0); + + mime = virDomainScreenshot(dom, st, screen, flags); + if (mime == NULL) { + vshError(ctl, _("could not take a screenshot of %s"), name); + goto cleanup; + } + + if (virStreamRecvAll(st, cmdScreenshotSink, &fd) < 0) { + vshError(ctl, _("could not receive data from domain %s"), name); + goto cleanup; + } + + if (VIR_CLOSE(fd) < 0) { + vshError(ctl, _("cannot close file %s"), file); + goto cleanup; + } + + if (virStreamFinish(st) < 0) { + vshError(ctl, _("cannot close stream on domain %s"), name); + goto cleanup; + } + + vshPrint(ctl, _("Screenshot saved to %s it's type is %s"), file, mime); + ret = true; + +cleanup: + if (ret == false && created) + unlink(file); + if (generated) + VIR_FREE(file); + virDomainFree(dom); + if (st) + virStreamFree(st); + VIR_FORCE_CLOSE(fd); + return ret; +} + /* * "resume" command */ @@ -10750,6 +10901,7 @@ static const vshCmdDef domManagementCmds[] = { {"resume", cmdResume, opts_resume, info_resume}, {"save", cmdSave, opts_save, info_save}, {"schedinfo", cmdSchedinfo, opts_schedinfo, info_schedinfo}, + {"screenshot", cmdScreenshot, opts_screenshot, info_screenshot}, {"setmaxmem", cmdSetmaxmem, opts_setmaxmem, info_setmaxmem}, {"setmem", cmdSetmem, opts_setmem, info_setmem}, {"setvcpus", cmdSetvcpus, opts_setvcpus, info_setvcpus}, diff --git a/tools/virsh.pod b/tools/virsh.pod index d11a0e3..5390f19 100644 --- a/tools/virsh.pod +++ b/tools/virsh.pod @@ -589,6 +589,15 @@ Therefore, -1 is a useful shorthand for 262144. B<Note>: The weight and cap parameters are defined only for the XEN_CREDIT scheduler and are now I<DEPRECATED>. +=item B<screenshot> I<domain-id> I<imagefilepath> optional I<--screen> B<screenID> + +Takes a screenshot of a current domain console and stores it into a file. +Optionally, if hypervisor supports more displays for a domain, I<screenID> +allows to specify from which should be the screenshot taken. It is the +sequential number of screen. In case of multiple graphics cards, heads +are enumerated before devices, e.g. having two graphics cards, both with +four heads, screen ID 5 addresses the second head on the second card. + =item B<setmem> I<domain-id> B<kilobytes> optional I<--config> I<--live> I<--current> -- 1.7.5.rc3