[libvirt] [PATCH v3] 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 diff to v2: - Eric's review suggestions included src/libvirt.c | 2 +- tools/virsh.c | 187 +++++++++++++++++++++++++++++++++++++++++++++++++++--- tools/virsh.pod | 9 +++ 3 files changed, 186 insertions(+), 12 deletions(-) diff --git a/src/libvirt.c b/src/libvirt.c index ee5c7cd..eaae0ec 100644 --- a/src/libvirt.c +++ b/src/libvirt.c @@ -2464,7 +2464,7 @@ 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 dfd5bd2..da10a0b 100644 --- a/tools/virsh.c +++ b/tools/virsh.c @@ -264,6 +264,9 @@ static bool vshCmdGrpHelp(vshControl *ctl, const char *name); static vshCmdOpt *vshCommandOpt(const vshCmd *cmd, const char *name); static int vshCommandOptInt(const vshCmd *cmd, const char *name, int *value) ATTRIBUTE_NONNULL(3) ATTRIBUTE_RETURN_CHECK; +static int vshCommandOptUInt(const vshCmd *cmd, const char *name, + unsigned int *value) + ATTRIBUTE_NONNULL(3) ATTRIBUTE_RETURN_CHECK; static int vshCommandOptUL(const vshCmd *cmd, const char *name, unsigned long *value) ATTRIBUTE_NONNULL(3) ATTRIBUTE_RETURN_CHECK; @@ -1938,6 +1941,153 @@ 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 vshStreamSink(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 * +vshGenFileName(vshControl *ctl, virDomainPtr dom, const char *mime) +{ + char timestr[100]; + struct timeval cur_time; + struct tm time_info; + const char *ext = 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 (STREQ(mime, "image/x-portable-pixmap")) + ext = ".ppm"; + else if (STREQ(mime, "image/png")) + ext = ".png"; + /* add mime type 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 NULL; + } + + 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 (vshCommandOptUInt(cmd, "screen", &screen) < 0) { + vshError(ctl, "%s", _("invalid screen ID")); + return false; + } + + if (!(dom = vshCommandOptDomain(ctl, cmd, &name))) + return false; + + st = virStreamNew(ctl->conn, 0); + + mime = virDomainScreenshot(dom, st, screen, flags); + if (!mime) { + vshError(ctl, _("could not take a screenshot of %s"), name); + goto cleanup; + } + + if (!file) { + if (!(file=vshGenFileName(ctl, dom, mime))) + 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; + } + } + + if (virStreamRecvAll(st, vshStreamSink, &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, with type of %s"), file, mime); + ret = true; + +cleanup: + if (!ret && created) + unlink(file); + if (generated) + VIR_FREE(file); + virDomainFree(dom); + if (st) + virStreamFree(st); + VIR_FORCE_CLOSE(fd); + return ret; +} + /* * "resume" command */ @@ -7451,16 +7601,6 @@ static const vshCmdOptDef opts_vol_download[] = { {NULL, 0, 0, NULL} }; - -static int -cmdVolDownloadSink(virStreamPtr st ATTRIBUTE_UNUSED, - const char *bytes, size_t nbytes, void *opaque) -{ - int *fd = opaque; - - return safewrite(*fd, bytes, nbytes); -} - static bool cmdVolDownload (vshControl *ctl, const vshCmd *cmd) { @@ -7510,7 +7650,7 @@ cmdVolDownload (vshControl *ctl, const vshCmd *cmd) goto cleanup; } - if (virStreamRecvAll(st, cmdVolDownloadSink, &fd) < 0) { + if (virStreamRecvAll(st, vshStreamSink, &fd) < 0) { vshError(ctl, _("cannot receive data from volume %s"), name); goto cleanup; } @@ -10945,6 +11085,7 @@ static const vshCmdDef domManagementCmds[] = { {"resume", cmdResume, opts_resume, info_resume, 0}, {"save", cmdSave, opts_save, info_save, 0}, {"schedinfo", cmdSchedinfo, opts_schedinfo, info_schedinfo, 0}, + {"screenshot", cmdScreenshot, opts_screenshot, info_screenshot, 0}, {"setmaxmem", cmdSetmaxmem, opts_setmaxmem, info_setmaxmem, 0}, {"setmem", cmdSetmem, opts_setmem, info_setmem, 0}, {"setvcpus", cmdSetvcpus, opts_setvcpus, info_setvcpus, 0}, @@ -11527,6 +11668,30 @@ vshCommandOptInt(const vshCmd *cmd, const char *name, int *value) return ret; } + +/* + * Convert option to unsigned int + * See vshCommandOptInt() + */ +static int +vshCommandOptUInt(const vshCmd *cmd, const char *name, unsigned int *value) +{ + vshCmdOpt *arg = vshCommandOpt(cmd, name); + unsigned int ret = 0, num; + char *end_p = NULL; + + if ((arg != NULL) && (arg->data != NULL)) { + num = strtoul(arg->data, &end_p, 10); + ret = -1; + if ((arg->data != end_p) && (*end_p == 0)) { + *value = num; + ret = 1; + } + } + return ret; +} + + /* * Convert option to unsigned long * See vshCommandOptInt() diff --git a/tools/virsh.pod b/tools/virsh.pod index 9251db6..e4a11d5 100644 --- a/tools/virsh.pod +++ b/tools/virsh.pod @@ -596,6 +596,15 @@ 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> optional I<imagefilepath> 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 which screen will be captured. 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