1 /*
2  * Copyright (c) 2023 Benjamin Stürz <benni@stuerz.xyz>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 #define _XOPEN_SOURCE 700
17 #define _BSD_SOURCE 1
18 #define DKTYPENAMES
19 #include <stddef.h>
20 #include <sys/cdefs.h>
21 #include <sys/types.h>
22 #include <sys/disklabel.h>
23 #include <sys/sysctl.h>
24 #include <sys/ioctl.h>
25 #include <sys/mount.h>
26 #include <sys/dkio.h>
27 #include <inttypes.h>
28 #include <stdbool.h>
29 #include <string.h>
30 #include <stdarg.h>
31 #include <stdint.h>
32 #include <stdlib.h>
33 #include <unistd.h>
34 #include <stdio.h>
35 #include <fcntl.h>
36 #include <errno.h>
37 
38 static __dead void die (const char *fmt, ...)
39 {
40     va_list ap;
41 
42     va_start (ap, fmt);
43     fputs ("Error: ", stderr);
44     vfprintf (stderr, fmt, ap);
45 
46     if (errno != 0) {
47         fprintf (stderr, ": %s\n", strerror (errno));
48     } else {
49         fputc ('\n', stderr);
50     }
51 
52     exit (1);
53 }
54 
55 static int diskcount (void)
56 {
57     const int mib[2] = { CTL_HW, HW_DISKCOUNT };
58     int diskcount;
59     size_t len = sizeof diskcount;
60 
61     if (sysctl (mib, 2, &diskcount, &len, NULL, 0) == -1)
62         die ("sysctl(hw.diskcount)");
63 
64     return diskcount;
65 }
66 
67 static char *disknames (void)
68 {
69     const int num = diskcount ();
70     const int mib[2] = { CTL_HW, HW_DISKNAMES };
71     size_t len = 32 * num;
72     char *buffer = malloc (len);
73 
74     if (sysctl (mib, 2, buffer, &len, NULL, 0) == -1)
75         die ("sysctl(hw.disknames)");
76 
77     return buffer;
78 }
79 
80 static char *stripdisk (char *n)
81 {
82     const char sufx[] = " disk";
83     const size_t ln = strnlen (n, 16);
84     const size_t ls = sizeof sufx - 1;
85 
86     if (!memcmp (n + ln - ls, sufx, ls)) {
87         n[ln - ls] = '\0';
88     }
89 
90     return n;
91 }
92 
93 static void print_size (uint64_t sz)
94 {
95     struct unit {
96         char sym;
97         uint64_t factor;
98     };
99 
100     const struct unit units[] = {
101         { 'P', 1ull << 50 },
102         { 'T', 1ull << 40 },
103         { 'G', 1ull << 30 },
104         { 'M', 1ull << 20 },
105         { 'K', 1ull << 10 },
106         { '0', 0 },
107     };
108 
109     char sym = 'B';
110     uint64_t factor = 1;
111 
112     for (const struct unit *u = &units[0]; u->factor; ++u) {
113         if (sz >= (u->factor * 9 / 10)) {
114             sym = u->sym;
115             factor = u->factor;
116             break;
117         }
118     }
119 
120     const unsigned scaled10 = sz * 10 / factor;
121     const unsigned scaled = sz / factor;
122     if (scaled10 >= 1000) {
123         printf ("%u", scaled);
124     } else if (scaled10 >= 100) {
125         printf (" %u", scaled);
126     } else {
127         printf ("%u.%u", scaled, scaled10 % 10);
128     }
129 
130     putchar (sym);
131     putchar (' ');
132 }
133 
134 enum {
135     FIELD_NAME      = 0x01,
136     FIELD_SIZE      = 0x02,
137     FIELD_USED      = 0x04,
138     FIELD_FREE      = 0x08,
139     FIELD_TYPE      = 0x10,
140     FIELD_LMNT      = 0x20,
141 
142     FIELD_DEFAULT   = FIELD_NAME | FIELD_SIZE | FIELD_TYPE | FIELD_LMNT,
143 };
144 
145 enum {
146     OPT_NOHEADER    = 0x01,
147     OPT_NOUNICODE   = 0x02,
148 };
149 
150 struct my_partinfo {
151     char name[5];
152     uint64_t size;
153     uint64_t fssize;
154     uint64_t free;
155     const char *fstype;
156     const char *mount;
157 };
158 
159 struct my_diskinfo {
160     char type[16];
161     char label[16];
162     char name[4];
163     uint64_t size;
164     uint64_t used;
165     uint8_t num_parts;
166     struct my_partinfo parts[MAXPARTITIONS];
167 };
168 
169 static void print_header (int fields)
170 {
171     if (fields & FIELD_NAME)
172         printf ("%-6s ", "NAME");
173 
174     if (fields & FIELD_SIZE)
175         printf ("%-4s ", "SIZE");
176 
177     if (fields & FIELD_USED)
178         printf ("%-4s ", "USED");
179 
180     if (fields & FIELD_FREE)
181         printf ("%-4s ", "FREE");
182 
183     if (fields & FIELD_TYPE)
184         printf ("%-8s ", "TYPE");
185 
186     if (fields & FIELD_LMNT)
187         printf ("LABEL/MOUNT ");
188 
189     putchar ('\n');
190 }
191 
192 static void print_part (const struct my_partinfo *part, int fields, int options, bool last)
193 {
194     if (fields & FIELD_NAME) {
195         const char *prefix = (options & OPT_NOUNICODE) ? "  " : (last ? "└─" : "├─");
196         printf ("%s%s ", prefix, part->name);
197     }
198 
199     if (fields & FIELD_SIZE)
200         print_size (part->size);
201 
202     if (fields & FIELD_USED) {
203         if (part->fssize) {
204             print_size (part->fssize - part->free);
205         } else {
206             printf (" N/A ");
207         }
208     }
209 
210     if (fields & FIELD_FREE) {
211         if (part->fssize) {
212             print_size (part->free);
213         } else {
214             printf (" N/A ");
215         }
216     }
217 
218     if (fields & FIELD_TYPE)
219         printf ("%-8.16s ", part->fstype);
220 
221     if (fields & FIELD_LMNT && part->mount)
222         printf ("%s ", part->mount);
223 
224     putchar ('\n');
225 }
226 
227 static void print_disk (const struct my_diskinfo *disk, int fields, int options)
228 {
229     if (fields & FIELD_NAME)
230         printf ("%s    ", disk->name);
231 
232     if (fields & FIELD_SIZE)
233         print_size (disk->size);
234 
235     if (fields & FIELD_USED)
236         print_size (disk->used);
237 
238     if (fields & FIELD_FREE)
239         print_size (disk->size - disk->used);
240 
241     // Pad only upto 8 characters because most disk types are <=8 bytes long.
242     if (fields & FIELD_TYPE)
243         printf ("%-8.16s ", disk->type);
244 
245     if (fields & FIELD_LMNT)
246         printf ("%.16s ", disk->label);
247 
248     putchar ('\n');
249 
250     for (uint8_t i = 0; i < disk->num_parts; ++i)
251         print_part (&disk->parts[i], fields, options, i == (disk->num_parts - 1));
252 }
253 
254 static const struct statfs *find_mount (const char *dev)
255 {
256     static struct statfs *mounts = NULL;
257     static int n_mounts;
258 
259     if (!mounts) {
260         n_mounts = getmntinfo (&mounts, MNT_NOWAIT);
261         if (n_mounts == 0)
262             die ("getmntinfo()");
263     }
264 
265     for (int i = 0; i < n_mounts; ++i) {
266         if (!strcmp (dev, mounts[i].f_mntfromname))
267             return &mounts[i];
268     }
269 
270     return NULL;
271 }
272 
273 static struct my_diskinfo read_disk (const char *name)
274 {
275     struct my_diskinfo disk;
276     struct disklabel label;
277 
278     bzero (&disk, sizeof disk);
279 
280     {   // Read disklabel.
281         char path[5 + 4 + 1];
282         int fd;
283 
284         snprintf (path, sizeof path, "/dev/%.3sc", name);
285         fd = open (path, O_RDONLY);
286         if (fd < 0)
287             die ("open(%s)", path);
288         if (ioctl (fd, DIOCGDINFO, &label) < 0)
289             die ("ioctl(%s, DIOCGDINFO)", path);
290         close (fd);
291     }
292 
293     memcpy (disk.name, name, 3);
294     disk.name[3] = '\0';
295     disk.size = DL_GETDSIZE (&label) * label.d_secsize;
296     memcpy (disk.type, label.d_typename, 16);
297     stripdisk (disk.type);
298     memcpy (disk.label, label.d_packname, 16);
299     disk.num_parts = 0;
300 
301     for (uint16_t i = 0; i < label.d_npartitions; ++i) {
302         const struct partition *p = &label.d_partitions[i];
303         const struct statfs *mnt;
304         struct my_partinfo part;
305         char path[5 + 4 + 1];
306 
307         bzero (&part, sizeof part);
308 
309         part.size = DL_GETPSIZE (p) * label.d_secsize;
310 
311         if (!part.size)
312             continue;
313 
314         memcpy (part.name, disk.name, 3);
315         part.name[3] = 'a' + i;
316         part.name[4] = '\0';
317 
318         snprintf (path, sizeof path, "/dev/%s", part.name);
319         mnt = find_mount (path);
320 
321         if (mnt) {
322             const uint64_t bs = mnt->f_bsize;
323             part.mount = mnt->f_mntonname;
324             part.fssize = mnt->f_blocks * bs;
325             part.free = mnt->f_bfree * bs;
326         }
327 
328         part.fstype = fstypenames[p->p_fstype];
329         if (i != 2)
330             disk.used += part.size;
331         disk.parts[disk.num_parts++] = part;
332     }
333 
334     return disk;
335 }
336 
337 static int usage (void)
338 {
339     fputs ("Usage: lsblk [-Vainu]\n", stderr);
340     return 1;
341 }
342 
343 int main (int argc, char *argv[])
344 {
345     int option;
346     int fields = FIELD_DEFAULT;
347     int options = 0;
348 
349     if (unveil ("/dev", "r") == -1)
350         die ("unveil(/dev)");
351 
352     if (unveil (NULL, NULL) == -1)
353         die ("unveil()");
354 
355     while ((option = getopt (argc, argv, ":Vainu")) != -1) {
356         switch (option) {
357         case 'V':
358             puts ("lsblk-" VERSION);
359             return 0;
360         case 'a':
361             fields = -1;
362             break;
363         case 'i':
364             options |= OPT_NOUNICODE;
365             break;
366         case 'n':
367             options |= OPT_NOHEADER;
368             break;
369         case 'u':
370             fields |= FIELD_USED | FIELD_FREE;
371             break;
372         default:
373             return usage ();
374         }
375     }
376 
377     if (argc != optind)
378         return usage ();
379 
380     struct statfs *mounts;
381     char *names = disknames ();
382 
383     if (pledge ("stdio rpath disklabel", NULL) == -1)
384         die ("pledge()");
385 
386     const int n_mounts = getmntinfo (&mounts, MNT_NOWAIT);
387     if (n_mounts == 0)
388         die ("getmntinfo()");
389 
390     size_t cap_disks = 10;
391     size_t num_disks = 0;
392     struct my_diskinfo *disks = calloc (cap_disks, sizeof (struct my_diskinfo));
393 
394     for (char *disk; (disk = strsep (&names, ",")) != NULL; ) {
395         if (num_disks == cap_disks) {
396             cap_disks = cap_disks * 13 / 8;
397             disks = reallocarray (disks, cap_disks, sizeof (struct my_diskinfo));
398         }
399         disks[num_disks++] = read_disk (disk);
400     }
401 
402     free (names);
403 
404     if (!(options & OPT_NOHEADER))
405         print_header (fields);
406 
407     for (size_t i = 0; i < num_disks; ++i) {
408         print_disk (&disks[i], fields, options);
409     }
410     return 0;
411 }