libbb/procps.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Utility routines.
   4  *
   5  * Copyright 1998 by Albert Cahalan; all rights reserved.
   6  * Copyright (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
   7  * SELinux support: (c) 2007 by Yuichi Nakamura <ynakam@hitachisoft.jp>
   8  *
   9  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  10  */
  11
  12 #include "libbb.h"
  13
  14
  15 typedef struct unsigned_to_name_map_t {
  16         long id;
  17         char name[USERNAME_MAX_SIZE];
  18 } unsigned_to_name_map_t;
  19
  20 typedef struct cache_t {
  21         unsigned_to_name_map_t *cache;
  22         int size;
  23 } cache_t;
  24
  25 static cache_t username, groupname;
  26
  27 static void clear_cache(cache_t *cp)
  28 {
  29         free(cp->cache);
  30         cp->cache = NULL;
  31         cp->size = 0;
  32 }
  33 void FAST_FUNC clear_username_cache(void)
  34 {
  35         clear_cache(&username);
  36         clear_cache(&groupname);
  37 }
  38
  39 #if 0 /* more generic, but we don't need that yet */
  40 /* Returns -N-1 if not found. */
  41 /* cp->cache[N] is allocated and must be filled in this case */
  42 static int get_cached(cache_t *cp, unsigned id)
  43 {
  44         int i;
  45         for (i = 0; i < cp->size; i++)
  46                 if (cp->cache[i].id == id)
  47                         return i;
  48         i = cp->size++;
  49         cp->cache = xrealloc_vector(cp->cache, 2, i);
  50         cp->cache[i++].id = id;
  51         return -i;
  52 }
  53 #endif
  54
  55 static char* get_cached(cache_t *cp, long id,
  56                         char* FAST_FUNC x2x_utoa(long id))
  57 {
  58         int i;
  59         for (i = 0; i < cp->size; i++)
  60                 if (cp->cache[i].id == id)
  61                         return cp->cache[i].name;
  62         i = cp->size++;
  63         cp->cache = xrealloc_vector(cp->cache, 2, i);
  64         cp->cache[i].id = id;
  65         /* Never fails. Generates numeric string if name isn't found */
  66         safe_strncpy(cp->cache[i].name, x2x_utoa(id), sizeof(cp->cache[i].name));
  67         return cp->cache[i].name;
  68 }
  69 const char* FAST_FUNC get_cached_username(uid_t uid)
  70 {
  71         return get_cached(&username, uid, uid2uname_utoa);
  72 }
  73 const char* FAST_FUNC get_cached_groupname(gid_t gid)
  74 {
  75         return get_cached(&groupname, gid, gid2group_utoa);
  76 }
  77
  78
  79 #define PROCPS_BUFSIZE 1024
  80
  81 static int read_to_buf(const char *filename, void *buf)
  82 {
  83         int fd;
  84         /* open_read_close() would do two reads, checking for EOF.
  85          * When you have 10000 /proc/$NUM/stat to read, it isn't desirable */
  86         ssize_t ret = -1;
  87         fd = open(filename, O_RDONLY);
  88         if (fd >= 0) {
  89                 ret = read(fd, buf, PROCPS_BUFSIZE-1);
  90                 close(fd);
  91         }
  92         ((char *)buf)[ret > 0 ? ret : 0] = '\0';
  93         return ret;
  94 }
  95
  96 static procps_status_t* FAST_FUNC alloc_procps_scan(void)
  97 {
  98         unsigned n = getpagesize();
  99         procps_status_t* sp = xzalloc(sizeof(procps_status_t));
 100         sp->dir = xopendir("/proc");
 101         while (1) {
 102                 n >>= 1;
 103                 if (!n) break;
 104                 sp->shift_pages_to_bytes++;
 105         }
 106         sp->shift_pages_to_kb = sp->shift_pages_to_bytes - 10;
 107         return sp;
 108 }
 109
 110 void FAST_FUNC free_procps_scan(procps_status_t* sp)
 111 {
 112         closedir(sp->dir);
 113         free(sp->argv0);
 114         free(sp->exe);
 115         IF_SELINUX(free(sp->context);)
 116         free(sp);
 117 }
 118
 119 #if ENABLE_FEATURE_TOPMEM
 120 static unsigned long fast_strtoul_16(char **endptr)
 121 {
 122         unsigned char c;
 123         char *str = *endptr;
 124         unsigned long n = 0;
 125
 126         while ((c = *str++) != ' ') {
 127                 c = ((c|0x20) - '0');
 128                 if (c > 9)
 129                         // c = c + '0' - 'a' + 10:
 130                         c = c - ('a' - '0' - 10);
 131                 n = n*16 + c;
 132         }
 133         *endptr = str; /* We skip trailing space! */
 134         return n;
 135 }
 136 /* TOPMEM uses fast_strtoul_10, so... */
 137 #undef ENABLE_FEATURE_FAST_TOP
 138 #define ENABLE_FEATURE_FAST_TOP 1
 139 #endif
 140
 141 #if ENABLE_FEATURE_FAST_TOP
 142 /* We cut a lot of corners here for speed */
 143 static unsigned long fast_strtoul_10(char **endptr)
 144 {
 145         char c;
 146         char *str = *endptr;
 147         unsigned long n = *str - '0';
 148
 149         while ((c = *++str) != ' ')
 150                 n = n*10 + (c - '0');
 151
 152         *endptr = str + 1; /* We skip trailing space! */
 153         return n;
 154 }
 155
 156 static long fast_strtol_10(char **endptr)
 157 {
 158         if (**endptr != '-')
 159                 return fast_strtoul_10(endptr);
 160
 161         (*endptr)++;
 162         return - (long)fast_strtoul_10(endptr);
 163 }
 164
 165 static char *skip_fields(char *str, int count)
 166 {
 167         do {
 168                 while (*str++ != ' ')
 169                         continue;
 170                 /* we found a space char, str points after it */
 171         } while (--count);
 172         return str;
 173 }
 174 #endif
 175
 176 void BUG_comm_size(void);
 177 procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
 178 {
 179         struct dirent *entry;
 180         char buf[PROCPS_BUFSIZE];
 181         char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
 182         char *filename_tail;
 183         long tasknice;
 184         unsigned pid;
 185         int n;
 186         struct stat sb;
 187
 188         if (!sp)
 189                 sp = alloc_procps_scan();
 190
 191         for (;;) {
 192                 entry = readdir(sp->dir);
 193                 if (entry == NULL) {
 194                         free_procps_scan(sp);
 195                         return NULL;
 196                 }
 197                 pid = bb_strtou(entry->d_name, NULL, 10);
 198                 if (errno)
 199                         continue;
 200
 201                 /* After this point we have to break, not continue
 202                  * ("continue" would mean that current /proc/NNN
 203                  * is not a valid process info) */
 204
 205                 memset(&sp->vsz, 0, sizeof(*sp) - offsetof(procps_status_t, vsz));
 206
 207                 sp->pid = pid;
 208                 if (!(flags & ~PSSCAN_PID)) break;
 209
 210 #if ENABLE_SELINUX
 211                 if (flags & PSSCAN_CONTEXT) {
 212                         if (getpidcon(sp->pid, &sp->context) < 0)
 213                                 sp->context = NULL;
 214                 }
 215 #endif
 216
 217                 filename_tail = filename + sprintf(filename, "/proc/%u/", pid);
 218
 219                 if (flags & PSSCAN_UIDGID) {
 220                         if (stat(filename, &sb))
 221                                 break;
 222                         /* Effective UID/GID, not real */
 223                         sp->uid = sb.st_uid;
 224                         sp->gid = sb.st_gid;
 225                 }
 226
 227                 if (flags & PSSCAN_STAT) {
 228                         char *cp, *comm1;
 229                         int tty;
 230 #if !ENABLE_FEATURE_FAST_TOP
 231                         unsigned long vsz, rss;
 232 #endif
 233                         /* see proc(5) for some details on this */
 234                         strcpy(filename_tail, "stat");
 235                         n = read_to_buf(filename, buf);
 236                         if (n < 0)
 237                                 break;
 238                         cp = strrchr(buf, ')'); /* split into "PID (cmd" and "<rest>" */
 239                         /*if (!cp || cp[1] != ' ')
 240                                 break;*/
 241                         cp[0] = '\0';
 242                         if (sizeof(sp->comm) < 16)
 243                                 BUG_comm_size();
 244                         comm1 = strchr(buf, '(');
 245                         /*if (comm1)*/
 246                                 safe_strncpy(sp->comm, comm1 + 1, sizeof(sp->comm));
 247
 248 #if !ENABLE_FEATURE_FAST_TOP
 249                         n = sscanf(cp+2,
 250                                 "%c %u "               /* state, ppid */
 251                                 "%u %u %d %*s "        /* pgid, sid, tty, tpgid */
 252                                 "%*s %*s %*s %*s %*s " /* flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
 253                                 "%lu %lu "             /* utime, stime */
 254                                 "%*s %*s %*s "         /* cutime, cstime, priority */
 255                                 "%ld "                 /* nice */
 256                                 "%*s %*s "             /* timeout, it_real_value */
 257                                 "%lu "                 /* start_time */
 258                                 "%lu "                 /* vsize */
 259                                 "%lu "                 /* rss */
 260 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 261                                 "%*s %*s %*s %*s %*s %*s " /*rss_rlim, start_code, end_code, start_stack, kstk_esp, kstk_eip */
 262                                 "%*s %*s %*s %*s "         /*signal, blocked, sigignore, sigcatch */
 263                                 "%*s %*s %*s %*s "         /*wchan, nswap, cnswap, exit_signal */
 264                                 "%d"                       /*cpu last seen on*/
 265 #endif
 266                                 ,
 267                                 sp->state, &sp->ppid,
 268                                 &sp->pgid, &sp->sid, &tty,
 269                                 &sp->utime, &sp->stime,
 270                                 &tasknice,
 271                                 &sp->start_time,
 272                                 &vsz,
 273                                 &rss
 274 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 275                                 , &sp->last_seen_on_cpu
 276 #endif
 277                                 );
 278
 279                         if (n < 11)
 280                                 break;
 281 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 282                         if (n < 11+15)
 283                                 sp->last_seen_on_cpu = 0;
 284 #endif
 285
 286                         /* vsz is in bytes and we want kb */
 287                         sp->vsz = vsz >> 10;
 288                         /* vsz is in bytes but rss is in *PAGES*! Can you believe that? */
 289                         sp->rss = rss << sp->shift_pages_to_kb;
 290                         sp->tty_major = (tty >> 8) & 0xfff;
 291                         sp->tty_minor = (tty & 0xff) | ((tty >> 12) & 0xfff00);
 292 #else
 293 /* This costs ~100 bytes more but makes top faster by 20%
 294  * If you run 10000 processes, this may be important for you */
 295                         sp->state[0] = cp[2];
 296                         cp += 4;
 297                         sp->ppid = fast_strtoul_10(&cp);
 298                         sp->pgid = fast_strtoul_10(&cp);
 299                         sp->sid = fast_strtoul_10(&cp);
 300                         tty = fast_strtoul_10(&cp);
 301                         sp->tty_major = (tty >> 8) & 0xfff;
 302                         sp->tty_minor = (tty & 0xff) | ((tty >> 12) & 0xfff00);
 303                         cp = skip_fields(cp, 6); /* tpgid, flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
 304                         sp->utime = fast_strtoul_10(&cp);
 305                         sp->stime = fast_strtoul_10(&cp);
 306                         cp = skip_fields(cp, 3); /* cutime, cstime, priority */
 307                         tasknice = fast_strtol_10(&cp);
 308                         cp = skip_fields(cp, 2); /* timeout, it_real_value */
 309                         sp->start_time = fast_strtoul_10(&cp);
 310                         /* vsz is in bytes and we want kb */
 311                         sp->vsz = fast_strtoul_10(&cp) >> 10;
 312                         /* vsz is in bytes but rss is in *PAGES*! Can you believe that? */
 313                         sp->rss = fast_strtoul_10(&cp) << sp->shift_pages_to_kb;
 314 #if ENABLE_FEATURE_TOP_SMP_PROCESS
 315                         /* (6): rss_rlim, start_code, end_code, start_stack, kstk_esp, kstk_eip */
 316                         /* (4): signal, blocked, sigignore, sigcatch */
 317                         /* (4): wchan, nswap, cnswap, exit_signal */
 318                         cp = skip_fields(cp, 14);
 319 //FIXME: is it safe to assume this field exists?
 320                         sp->last_seen_on_cpu = fast_strtoul_10(&cp);
 321 #endif
 322 #endif /* end of !ENABLE_FEATURE_TOP_SMP_PROCESS */
 323
 324 #if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
 325                         sp->niceness = tasknice;
 326 #endif
 327
 328                         if (sp->vsz == 0 && sp->state[0] != 'Z')
 329                                 sp->state[1] = 'W';
 330                         else
 331                                 sp->state[1] = ' ';
 332                         if (tasknice < 0)
 333                                 sp->state[2] = '<';
 334                         else if (tasknice) /* > 0 */
 335                                 sp->state[2] = 'N';
 336                         else
 337                                 sp->state[2] = ' ';
 338                 }
 339
 340 #if ENABLE_FEATURE_TOPMEM
 341                 if (flags & (PSSCAN_SMAPS)) {
 342                         FILE *file;
 343
 344                         strcpy(filename_tail, "smaps");
 345                         file = fopen_for_read(filename);
 346                         if (!file)
 347                                 break;
 348                         while (fgets(buf, sizeof(buf), file)) {
 349                                 unsigned long sz;
 350                                 char *tp;
 351                                 char w;
 352 #define SCAN(str, name) \
 353         if (strncmp(buf, str, sizeof(str)-1) == 0) { \
 354                 tp = skip_whitespace(buf + sizeof(str)-1); \
 355                 sp->name += fast_strtoul_10(&tp); \
 356                 continue; \
 357         }
 358                                 SCAN("Shared_Clean:" , shared_clean );
 359                                 SCAN("Shared_Dirty:" , shared_dirty );
 360                                 SCAN("Private_Clean:", private_clean);
 361                                 SCAN("Private_Dirty:", private_dirty);
 362 #undef SCAN
 363                                 // f7d29000-f7d39000 rw-s ADR M:m OFS FILE
 364                                 tp = strchr(buf, '-');
 365                                 if (tp) {
 366                                         *tp = ' ';
 367                                         tp = buf;
 368                                         sz = fast_strtoul_16(&tp); /* start */
 369                                         sz = (fast_strtoul_16(&tp) - sz) >> 10; /* end - start */
 370                                         // tp -> "rw-s" string
 371                                         w = tp[1];
 372                                         // skipping "rw-s ADR M:m OFS "
 373                                         tp = skip_whitespace(skip_fields(tp, 4));
 374                                         // filter out /dev/something (something != zero)
 375                                         if (strncmp(tp, "/dev/", 5) != 0 || strcmp(tp, "/dev/zero\n") == 0) {
 376                                                 if (w == 'w') {
 377                                                         sp->mapped_rw += sz;
 378                                                 } else if (w == '-') {
 379                                                         sp->mapped_ro += sz;
 380                                                 }
 381                                         }
 382 //else printf("DROPPING %s (%s)\n", buf, tp);
 383                                         if (strcmp(tp, "[stack]\n") == 0)
 384                                                 sp->stack += sz;
 385                                 }
 386                         }
 387                         fclose(file);
 388                 }
 389 #endif /* TOPMEM */
 390 #if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
 391                 if (flags & PSSCAN_RUIDGID) {
 392                         FILE *file;
 393
 394                         strcpy(filename_tail, "status");
 395                         file = fopen_for_read(filename);
 396                         if (!file)
 397                                 break;
 398                         while (fgets(buf, sizeof(buf), file)) {
 399                                 char *tp;
 400 #define SCAN_TWO(str, name, statement) \
 401         if (strncmp(buf, str, sizeof(str)-1) == 0) { \
 402                 tp = skip_whitespace(buf + sizeof(str)-1); \
 403                 sscanf(tp, "%u", &sp->name); \
 404                 statement; \
 405         }
 406                                 SCAN_TWO("Uid:", ruid, continue);
 407                                 SCAN_TWO("Gid:", rgid, break);
 408 #undef SCAN_TWO
 409                         }
 410                         fclose(file);
 411                 }
 412 #endif /* PS_ADDITIONAL_COLUMNS */
 413 #if 0 /* PSSCAN_CMD is not used */
 414                 if (flags & (PSSCAN_CMD|PSSCAN_ARGV0)) {
 415                         free(sp->argv0);
 416                         sp->argv0 = NULL;
 417                         free(sp->cmd);
 418                         sp->cmd = NULL;
 419                         strcpy(filename_tail, "cmdline");
 420                         /* TODO: to get rid of size limits, read into malloc buf,
 421                          * then realloc it down to real size. */
 422                         n = read_to_buf(filename, buf);
 423                         if (n <= 0)
 424                                 break;
 425                         if (flags & PSSCAN_ARGV0)
 426                                 sp->argv0 = xstrdup(buf);
 427                         if (flags & PSSCAN_CMD) {
 428                                 do {
 429                                         n--;
 430                                         if ((unsigned char)(buf[n]) < ' ')
 431                                                 buf[n] = ' ';
 432                                 } while (n);
 433                                 sp->cmd = xstrdup(buf);
 434                         }
 435                 }
 436 #else
 437                 if (flags & (PSSCAN_ARGV0|PSSCAN_ARGVN)) {
 438                         free(sp->argv0);
 439                         sp->argv0 = NULL;
 440                         strcpy(filename_tail, "cmdline");
 441                         n = read_to_buf(filename, buf);
 442                         if (n <= 0)
 443                                 break;
 444                         if (flags & PSSCAN_ARGVN) {
 445                                 sp->argv_len = n;
 446                                 sp->argv0 = xmalloc(n + 1);
 447                                 memcpy(sp->argv0, buf, n + 1);
 448                                 /* sp->argv0[n] = '\0'; - buf has it */
 449                         } else {
 450                                 sp->argv_len = 0;
 451                                 sp->argv0 = xstrdup(buf);
 452                         }
 453                 }
 454 #endif
 455                 if (flags & PSSCAN_EXE) {
 456                         strcpy(filename_tail, "exe");
 457                         free(sp->exe);
 458                         sp->exe = xmalloc_readlink(filename);
 459                 }
 460                 break;
 461         }
 462         return sp;
 463 }
 464
 465 void FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
 466 {
 467         ssize_t sz;
 468         char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
 469
 470         sprintf(filename, "/proc/%u/cmdline", pid);
 471         sz = open_read_close(filename, buf, col);
 472         if (sz > 0) {
 473                 buf[sz] = '\0';
 474                 while (--sz >= 0)
 475                         if ((unsigned char)(buf[sz]) < ' ')
 476                                 buf[sz] = ' ';
 477         } else {
 478                 snprintf(buf, col, "[%s]", comm);
 479         }
 480 }
 481
 482 /* from kernel:
 483         //             pid comm S ppid pgid sid tty_nr tty_pgrp flg
 484         sprintf(buffer,"%d (%s) %c %d  %d   %d  %d     %d       %lu %lu \
 485 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
 486 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %lu %lu %llu\n",
 487                 task->pid,
 488                 tcomm,
 489                 state,
 490                 ppid,
 491                 pgid,
 492                 sid,
 493                 tty_nr,
 494                 tty_pgrp,
 495                 task->flags,
 496                 min_flt,
 497                 cmin_flt,
 498                 maj_flt,
 499                 cmaj_flt,
 500                 cputime_to_clock_t(utime),
 501                 cputime_to_clock_t(stime),
 502                 cputime_to_clock_t(cutime),
 503                 cputime_to_clock_t(cstime),
 504                 priority,
 505                 nice,
 506                 num_threads,
 507                 // 0,
 508                 start_time,
 509                 vsize,
 510                 mm ? get_mm_rss(mm) : 0,
 511                 rsslim,
 512                 mm ? mm->start_code : 0,
 513                 mm ? mm->end_code : 0,
 514                 mm ? mm->start_stack : 0,
 515                 esp,
 516                 eip,
 517 the rest is some obsolete cruft
 518 */