diff options
Diffstat (limited to 'usr.bin/backlight/backlight.c')
| -rw-r--r-- | usr.bin/backlight/backlight.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/usr.bin/backlight/backlight.c b/usr.bin/backlight/backlight.c new file mode 100644 index 000000000000..de02bb82915d --- /dev/null +++ b/usr.bin/backlight/backlight.c @@ -0,0 +1,224 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2020 Emmanuel Vadot <manu@FreeBSD.org> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/types.h> +#include <sys/ioctl.h> +#include <stdbool.h> +#include <sys/capsicum.h> +#include <sys/backlight.h> + +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <capsicum_helpers.h> + +#define BACKLIGHT_QUERY 0x0001 +#define BACKLIGHT_SET_BRIGHTNESS 0x0002 +#define BACKLIGHT_INCR 0x0004 +#define BACKLIGHT_DECR 0x0008 +#define BACKLIGHT_INFO 0x0010 + +static char device_name[PATH_MAX] = "/dev/backlight/backlight0"; + +static void +set_device_name(const char *name) +{ + + if (name[0] == '/') + strlcpy(device_name, name, sizeof(device_name)); + else + snprintf(device_name, sizeof(device_name), "/dev/backlight/%s", name); +} + +static void +usage(void) +{ + fprintf(stderr, "Usage:\n"); + fprintf(stderr, "\tbacklight [-q] [-f device]\n"); + fprintf(stderr, "\tbacklight [-q] [-f device] -i\n"); + fprintf(stderr, "\tbacklight [-f device] value\n"); + fprintf(stderr, "\tbacklight [-f device] incr|+ value\n"); + fprintf(stderr, "\tbacklight [-f device] decr|- value\n"); + exit(1); +} + +static const char * +backlight_type_to_string(enum backlight_info_type type) +{ + switch (type) { + case BACKLIGHT_TYPE_PANEL: + return ("Panel"); + case BACKLIGHT_TYPE_KEYBOARD: + return ("Keyboard"); + } + + return ("Unknown"); +} + +int +main(int argc, char *argv[]) +{ + struct backlight_props props; + struct backlight_info info; + int fd; + int action, ch; + cap_rights_t right_ioctl; + const unsigned long backlight_ioctls[] = { + BACKLIGHTGETSTATUS, + BACKLIGHTUPDATESTATUS, + BACKLIGHTGETINFO}; + long percent = -1; + const char *percent_error; + uint32_t i; + bool quiet = false; + + action = BACKLIGHT_QUERY; + fd = -1; + + while ((ch = getopt(argc, argv, "f:qhi")) != -1) { + switch (ch) { + case 'q': + quiet = true; + break; + case 'f': + set_device_name(optarg); + break; + case 'i': + action = BACKLIGHT_INFO; + break; + case 'h': + usage(); + break; + } + } + + argc -= optind; + argv += optind; + if (argc != 0) { + if (strcmp("incr", argv[0]) == 0 || + strcmp("+", argv[0]) == 0) { + action = BACKLIGHT_INCR; + argc -= 1; + argv += 1; + } + else if (strcmp("decr", argv[0]) == 0 || + strcmp("-", argv[0]) == 0) { + action = BACKLIGHT_DECR; + argc -= 1; + argv += 1; + } else + action = BACKLIGHT_SET_BRIGHTNESS; + + if (argc == 1) { + /* ignore a trailing % for user friendlyness */ + if (strlen(argv[0]) > 0 && + argv[0][strlen(argv[0]) - 1] == '%') + argv[0][strlen(argv[0]) - 1] = '\0'; + percent = strtonum(argv[0], 0, 100, &percent_error); + if (percent_error) + errx(1, "Cannot parse brightness level %s: %s", + argv[0], + percent_error); + } + } + + if ((fd = open(device_name, O_RDWR)) == -1) + errx(1, "cannot open %s: %s", + device_name, strerror(errno)); + + if (caph_limit_stdio() < 0) + errx(1, "can't limit stdio rights"); + caph_cache_catpages(); + cap_rights_init(&right_ioctl, CAP_IOCTL); + if (caph_rights_limit(fd, &right_ioctl) < 0) + errx(1, "cap_right_limit() failed"); + if (caph_ioctls_limit(fd, backlight_ioctls, nitems(backlight_ioctls)) < 0) + errx(1, "caph_ioctls_limit() failed"); + if (caph_enter() < 0) + errx(1, "failed to enter capability mode"); + + switch (action) { + case BACKLIGHT_QUERY: + if (ioctl(fd, BACKLIGHTGETSTATUS, &props) == -1) + errx(1, "Cannot query the backlight device"); + if (quiet) + printf("%u\n", props.brightness); + else { + printf("brightness: %d\n", props.brightness); + if (props.nlevels != 0) { + printf("levels:"); + for (i = 0; i < props.nlevels; i++) + printf(" %d", props.levels[i]); + printf("\n"); + } + } + break; + case BACKLIGHT_SET_BRIGHTNESS: + if (percent == -1) + usage(); + props.brightness = percent; + if (ioctl(fd, BACKLIGHTUPDATESTATUS, &props) == -1) + errx(1, "Cannot update the backlight device"); + break; + case BACKLIGHT_INCR: + case BACKLIGHT_DECR: + if (percent == 0) + /* Avoid any ioctl if we don't have anything to do */ + break; + if (ioctl(fd, BACKLIGHTGETSTATUS, &props) == -1) + errx(1, "Cannot query the backlight device"); + percent = percent == -1 ? 10 : percent; + percent = action == BACKLIGHT_INCR ? percent : -percent; + props.brightness += percent; + if ((int)props.brightness < 0) + props.brightness = 0; + if (props.brightness > 100) + props.brightness = 100; + if (ioctl(fd, BACKLIGHTUPDATESTATUS, &props) == -1) + errx(1, "Cannot update the backlight device"); + break; + case BACKLIGHT_INFO: + if (ioctl(fd, BACKLIGHTGETINFO, &info) == -1) + errx(1, "Cannot query the backlight device"); + if (quiet == false) { + printf("Backlight name: %s\n", info.name); + printf("Backlight hardware type: %s\n", backlight_type_to_string(info.type)); + } else { + printf("%s\n", info.name); + printf("%s\n", backlight_type_to_string(info.type)); + } + break; + } + + close(fd); + return (0); +} |