C++ pager_open函数代码示例

int
command_lskern(int argc, char *argv[])
{
    struct preloaded_file	*fp;
    char			lbuf[80];
    int				ch, verbose;

    verbose = 0;
    optind = 1;
    optreset = 1;

    pager_open();
    for (fp = preloaded_files; fp; fp = fp->f_next) {
	snprintf(lbuf, sizeof(lbuf), " %p: %s (%s, 0x%lx)\n", 
		(void *) fp->f_addr, fp->f_name, fp->f_type, (long) fp->f_size);
	pager_output(lbuf);
	if (fp->f_args != NULL) {
	    pager_output("    args: ");
	    pager_output(fp->f_args);
	    pager_output("\n");
	}
    }
    pager_close();
    return(CMD_OK);
}

static int list_timezones(int argc, char **argv, void *userdata) {
        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
        sd_bus *bus = userdata;
        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
        int r;
        char** zones;

        r = sd_bus_call_method(bus,
                               "org.freedesktop.timedate1",
                               "/org/freedesktop/timedate1",
                               "org.freedesktop.timedate1",
                               "ListTimezones",
                               &error,
                               &reply,
                               NULL);
        if (r < 0)
                return log_error_errno(r, "Failed to request list of time zones: %s",
                                       bus_error_message(&error, r));

        r = sd_bus_message_read_strv(reply, &zones);
        if (r < 0)
                return bus_log_parse_error(r);

        (void) pager_open(arg_pager_flags);
        strv_print(zones);

        return 0;
}

static void
efipart_print(int verbose)
{
	char line[80];
	EFI_BLOCK_IO *blkio;
	EFI_HANDLE h;
	EFI_STATUS status;
	u_int unit;

	pager_open();
	for (unit = 0, h = efi_find_handle(&efipart_dev, 0);
	    h != NULL; h = efi_find_handle(&efipart_dev, ++unit)) {
		sprintf(line, "    %s%d:", efipart_dev.dv_name, unit);
		if (pager_output(line))
			break;

		status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
		if (!EFI_ERROR(status)) {
			sprintf(line, "    %llu blocks",
			    (unsigned long long)(blkio->Media->LastBlock + 1));
			if (pager_output(line))
				break;
			if (blkio->Media->RemovableMedia)
				if (pager_output(" (removable)"))
					break;
		}
		if (pager_output("\n"))
			break;
	}
	pager_close();
}

static void pager_open_if_enabled(void) {

        if (arg_no_pager)
                return;

        pager_open(false);
}

static void pager_open_if_enabled(void) {

        /* Cache result before we open the pager */
        if (arg_no_pager)
                return;

        pager_open(false);
}

static int list_timezones(int argc, char **argv, void *userdata) {
        _cleanup_strv_free_ char **zones = NULL;
        int r;

        r = get_timezones(&zones);
        if (r < 0)
                return log_error_errno(r, "Failed to read list of time zones: %m");

        (void) pager_open(arg_no_pager, false);
        strv_print(zones);

        return 0;
}

static int list_vconsole_keymaps(int argc, char **argv, void *userdata) {
        _cleanup_strv_free_ char **l = NULL;
        int r;

        r = get_keymaps(&l);
        if (r < 0)
                return log_error_errno(r, "Failed to read list of keymaps: %m");

        (void) pager_open(arg_no_pager, false);

        strv_print(l);

        return 0;
}

int main(int argc, char *argv[]) {
        int r, k;

        r = parse_argv(argc, argv);
        if (r <= 0)
                return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

        log_set_target(LOG_TARGET_AUTO);
        log_parse_environment();
        log_open();

        umask(0022);

        r = 0;

        if (argc > optind) {
                int i;

                for (i = optind; i < argc; i++) {
                        k = apply_file(argv[i], false);
                        if (k < 0 && r == 0)
                                r = k;
                }
        } else {
                _cleanup_strv_free_ char **files = NULL;
                char **f;

                r = conf_files_list_strv(&files, ".conf", NULL, 0, (const char**) CONF_PATHS_STRV("binfmt.d"));
                if (r < 0) {
                        log_error_errno(r, "Failed to enumerate binfmt.d files: %m");
                        goto finish;
                }

                if (arg_cat_config) {
                        (void) pager_open(arg_no_pager, false);

                        r = cat_files(NULL, files, 0);
                        goto finish;
                }

                /* Flush out all rules */
                write_string_file("/proc/sys/fs/binfmt_misc/status", "-1", 0);

                STRV_FOREACH(f, files) {
                        k = apply_file(*f, true);
                        if (k < 0 && r == 0)
                                r = k;
                }
        }

static int
command_configuration(int argc, char *argv[])
{
	char line[80];
	UINTN i;

	snprintf(line, sizeof(line), "NumberOfTableEntries=%lu\n",
		(unsigned long)ST->NumberOfTableEntries);
	pager_open();
	if (pager_output(line)) {
		pager_close();
		return (CMD_OK);
	}

	for (i = 0; i < ST->NumberOfTableEntries; i++) {
		EFI_GUID *guid;

		printf("  ");
		guid = &ST->ConfigurationTable[i].VendorGuid;
		if (!memcmp(guid, &mps, sizeof(EFI_GUID)))
			printf("MPS Table");
		else if (!memcmp(guid, &acpi, sizeof(EFI_GUID)))
			printf("ACPI Table");
		else if (!memcmp(guid, &acpi20, sizeof(EFI_GUID)))
			printf("ACPI 2.0 Table");
		else if (!memcmp(guid, &smbios, sizeof(EFI_GUID)))
			printf("SMBIOS Table %p",
			    ST->ConfigurationTable[i].VendorTable);
		else if (!memcmp(guid, &dxe, sizeof(EFI_GUID)))
			printf("DXE Table");
		else if (!memcmp(guid, &hoblist, sizeof(EFI_GUID)))
			printf("HOB List Table");
		else if (!memcmp(guid, &memtype, sizeof(EFI_GUID)))
			printf("Memory Type Information Table");
		else if (!memcmp(guid, &debugimg, sizeof(EFI_GUID)))
			printf("Debug Image Info Table");
		else if (!memcmp(guid, &fdtdtb, sizeof(EFI_GUID)))
			printf("FDT Table");
		else
			printf("Unknown Table (%s)", guid_to_string(guid));
		snprintf(line, sizeof(line), " at %p\n",
		    ST->ConfigurationTable[i].VendorTable);
		if (pager_output(line))
			break;
	}

	pager_close();
	return (CMD_OK);
}

static void
efinet_dev_print(int verbose)
{
	char line[80];
	EFI_HANDLE h;
	int unit;

	pager_open();
	for (unit = 0, h = efi_find_handle(&efinet_dev, 0);
	    h != NULL; h = efi_find_handle(&efinet_dev, ++unit)) {
		sprintf(line, "    %s%d:\n", efinet_dev.dv_name, unit);
		if (pager_output(line))
			break;
	}
	pager_close();
}

static int list_timezones(sd_bus *bus, char **args, unsigned n) {
        _cleanup_strv_free_ char **zones = NULL;
        int r;

        assert(args);
        assert(n == 1);

        r = get_timezones(&zones);
        if (r < 0)
                return log_error_errno(r, "Failed to read list of time zones: %m");

        pager_open(arg_no_pager, false);
        strv_print(zones);

        return 0;
}

static int
command_lsmod(int argc, char *argv[])
{
    struct loaded_module	*am;
    struct module_metadata	*md;
    char			lbuf[80];
    int				ch, verbose;

    verbose = 0;
    optind = 1;
    optreset = 1;
    while ((ch = getopt(argc, argv, "v")) != -1) {
	switch(ch) {
	case 'v':
	    verbose = 1;
	    break;
	case '?':
	default:
	    /* getopt has already reported an error */
	    return(CMD_OK);
	}
    }

    pager_open();
    for (am = loaded_modules; (am != NULL); am = am->m_next) {
	sprintf(lbuf, " %p: %s (%s, 0x%lx)\n", 
		(void *) am->m_addr, am->m_name, am->m_type, (long) am->m_size);
	pager_output(lbuf);
	if (am->m_args != NULL) {
	    pager_output("    args: ");
	    pager_output(am->m_args);
	    pager_output("\n");
	}
	if (verbose)
	    /* XXX could add some formatting smarts here to display some better */
	    for (md = am->m_metadata; md != NULL; md = md->md_next) {
		sprintf(lbuf, "      0x%04x, 0x%lx\n", md->md_type, (long) md->md_size);
		pager_output(lbuf);
	    }
    }
    pager_close();
    return(CMD_OK);
}

static void
efinet_dev_print(int verbose)
{
	CHAR16 *text;
	EFI_HANDLE h;
	int unit;

	pager_open();
	for (unit = 0, h = efi_find_handle(&efinet_dev, 0);
	    h != NULL; h = efi_find_handle(&efinet_dev, ++unit)) {
		printf("    %s%d:", efinet_dev.dv_name, unit);
		text = efi_devpath_name(efi_lookup_devpath(h));
		if (text != NULL) {
			printf("    %S", text);
			efi_free_devpath_name(text);
		}
		if (pager_output("\n"))
			break;
	}
	pager_close();
}

/*
 * Please note: although we use the pager for the list of commands,
 * this routine is called from the ? FORTH function which then
 * unconditionally prints some commands. This will lead to anomalous
 * behavior. There's no 'pager_output' binding to FORTH to allow
 * things to work right, so I'm documenting the bug rather than
 * fixing it.
 */
static int
command_commandlist(int argc, char *argv[])
{
    struct bootblk_command	**cmdp;
    int		res;
    char	name[20];

    res = 0;
    pager_open();
    res = pager_output("Available commands:\n");
    SET_FOREACH(cmdp, Xcommand_set) {
	if (res)
	    break;
	if (((*cmdp)->c_name != NULL) && ((*cmdp)->c_desc != NULL)) {
	    sprintf(name, "  %-15s  ", (*cmdp)->c_name);
	    pager_output(name);
	    pager_output((*cmdp)->c_desc);
	    res = pager_output("\n");
	}
    }
    pager_close();
    return(CMD_OK);
}

/*
 * Display a region in traditional hexdump format.
 */
void
hexdump(caddr_t region, size_t len)
{
    caddr_t	line;
    int		x, c;
    char	lbuf[80];
#define emit(fmt, args...)	{sprintf(lbuf, fmt , ## args); pager_output(lbuf);}

    pager_open();
    for (line = region; line < (region + len); line += 16) {
	emit("%08lx  ", (long) line);
	
	for (x = 0; x < 16; x++) {
	    if ((line + x) < (region + len)) {
		emit("%02x ", *(u_int8_t *)(line + x));
	    } else {
		emit("-- ");
	    }
	    if (x == 7)
		emit(" ");
	}
	emit(" |");
	for (x = 0; x < 16; x++) {
	    if ((line + x) < (region + len)) {
		c = *(u_int8_t *)(line + x);
		if ((c < ' ') || (c > '~'))	/* !isprint(c) */
		    c = '.';
		emit("%c", c);
	    } else {
		emit(" ");
	    }
	}
	emit("|\n");
    }
    pager_close();
}