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 #if ENABLE_FEATURE_SHOW_THREADS
 114         if (sp->task_dir)
 115                 closedir(sp->task_dir);
 116 #endif
 117         free(sp->argv0);
 118         free(sp->exe);
 119         IF_SELINUX(free(sp->context);)
 120         free(sp);
 121 }
 122
 123 #if ENABLE_FEATURE_TOPMEM
 124 static unsigned long fast_strtoul_16(char **endptr)
 125 {
 126         unsigned char c;
 127         char *str = *endptr;
 128         unsigned long n = 0;
 129
 130         while ((c = *str++) != ' ') {
 131                 c = ((c|0x20) - '0');
 132                 if (c > 9)
 133                         // c = c + '0' - 'a' + 10:
 134                         c = c - ('a' - '0' - 10);
 135                 n = n*16 + c;
 136         }
 137         *endptr = str; /* We skip trailing space! */
 138         return n;
 139 }
 140 /* TOPMEM uses fast_strtoul_10, so... */
 141 # undef ENABLE_FEATURE_FAST_TOP
 142 # define ENABLE_FEATURE_FAST_TOP 1
 143 #endif
 144
 145 #if ENABLE_FEATURE_FAST_TOP
 146 /* We cut a lot of corners here for speed */
 147 static unsigned long fast_strtoul_10(char **endptr)
 148 {
 149         char c;
 150         char *str = *endptr;
 151         unsigned long n = *str - '0';
 152
 153         while ((c = *++str) != ' ')
 154                 n = n*10 + (c - '0');
 155
 156         *endptr = str + 1; /* We skip trailing space! */
 157         return n;
 158 }
 159
 160 static long fast_strtol_10(char **endptr)
 161 {
 162         if (**endptr != '-')
 163                 return fast_strtoul_10(endptr);
 164
 165         (*endptr)++;
 166         return - (long)fast_strtoul_10(endptr);
 167 }
 168
 169 static char *skip_fields(char *str, int count)
 170 {
 171         do {
 172                 while (*str++ != ' ')
 173                         continue;
 174                 /* we found a space char, str points after it */
 175         } while (--count);
 176         return str;
 177 }
 178 #endif
 179
 180 void BUG_comm_size(void);
 181 procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
 182 {
 183         struct dirent *entry;
 184         char buf[PROCPS_BUFSIZE];
 185         char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
 186         char *filename_tail;
 187         long tasknice;
 188         unsigned pid;
 189         int n;
 190         struct stat sb;
 191
 192         if (!sp)
 193                 sp = alloc_procps_scan();
 194
 195         for (;;) {
 196 #if ENABLE_FEATURE_SHOW_THREADS
 197                 if ((flags & PSSCAN_TASKS) && sp->task_dir) {
 198                         entry = readdir(sp->task_dir);
 199                         if (entry)
 200                                 goto got_entry;
 201                         closedir(sp->task_dir);
 202                         sp->task_dir = NULL;
 203                 }
 204 #endif
 205                 entry = readdir(sp->dir);
 206                 if (entry == NULL) {
 207                         free_procps_scan(sp);
 208                         return NULL;
 209                 }
 210  IF_FEATURE_SHOW_THREADS(got_entry:)
 211                 pid = bb_strtou(entry->d_name, NULL, 10);
 212                 if (errno)
 213                         continue;
 214 #if ENABLE_FEATURE_SHOW_THREADS
 215                 if ((flags & PSSCAN_TASKS) && !sp->task_dir) {
 216                         /* We found another /proc/PID. Do not use it,
 217                          * there will be /proc/PID/task/PID (same PID!),
 218                          * so just go ahead and dive into /proc/PID/task. */
 219                         char task_dir[sizeof("/proc/%u/task") + sizeof(int)*3];
 220                         sprintf(task_dir, "/proc/%u/task", pid);
 221                         sp->task_dir = xopendir(task_dir);
 222                         continue;
 223                 }
 224 #endif
 225
 226                 /* After this point we can:
 227                  * "break": stop parsing, return the data
 228                  * "continue": try next /proc/XXX
 229                  */
 230
 231                 memset(&sp->vsz, 0, sizeof(*sp) - offsetof(procps_status_t, vsz));
 232
 233                 sp->pid = pid;
 234                 if (!(flags & ~PSSCAN_PID))
 235                         break; /* we needed only pid, we got it */
 236
 237 #if ENABLE_SELINUX
 238                 if (flags & PSSCAN_CONTEXT) {
 239                         if (getpidcon(sp->pid, &sp->context) < 0)
 240                                 sp->context = NULL;
 241                 }
 242 #endif
 243
 244                 filename_tail = filename + sprintf(filename, "/proc/%u/", pid);
 245
 246                 if (flags & PSSCAN_UIDGID) {
 247                         if (stat(filename, &sb))
 248                                 continue; /* process probably exited */
 249                         /* Effective UID/GID, not real */
 250                         sp->uid = sb.st_uid;
 251                         sp->gid = sb.st_gid;
 252                 }
 253
 254                 if (flags & PSSCAN_STAT) {
 255                         char *cp, *comm1;
 256                         int tty;
 257 #if !ENABLE_FEATURE_FAST_TOP
 258                         unsigned long vsz, rss;
 259 #endif
 260                         /* see proc(5) for some details on this */
 261                         strcpy(filename_tail, "stat");
 262                         n = read_to_buf(filename, buf);
 263                         if (n < 0)
 264                                 continue; /* process probably exited */
 265                         cp = strrchr(buf, ')'); /* split into "PID (cmd" and "<rest>" */
 266                         /*if (!cp || cp[1] != ' ')
 267                                 continue;*/
 268                         cp[0] = '\0';
 269                         if (sizeof(sp->comm) < 16)
 270                                 BUG_comm_size();
 271                         comm1 = strchr(buf, '(');
 272                         /*if (comm1)*/
 273                                 safe_strncpy(sp->comm, comm1 + 1, sizeof(sp->comm));
 274
 275 #if !ENABLE_FEATURE_FAST_TOP
 276                         n = sscanf(cp+2,
 277                                 "%c %u "               /* state, ppid */
 278                                 "%u %u %d %*s "        /* pgid, sid, tty, tpgid */
 279                                 "%*s %*s %*s %*s %*s " /* flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
 280                                 "%lu %lu "             /* utime, stime */
 281                                 "%*s %*s %*s "         /* cutime, cstime, priority */
 282                                 "%ld "                 /* nice */
 283                                 "%*s %*s "             /* timeout, it_real_value */
 284                                 "%lu "                 /* start_time */
 285                                 "%lu "                 /* vsize */
 286                                 "%lu "                 /* rss */
 287 # if ENABLE_FEATURE_TOP_SMP_PROCESS
 288                                 "%*s %*s %*s %*s %*s %*s " /*rss_rlim, start_code, end_code, start_stack, kstk_esp, kstk_eip */
 289                                 "%*s %*s %*s %*s "         /*signal, blocked, sigignore, sigcatch */
 290                                 "%*s %*s %*s %*s "         /*wchan, nswap, cnswap, exit_signal */
 291                                 "%d"                       /*cpu last seen on*/
 292 # endif
 293                                 ,
 294                                 sp->state, &sp->ppid,
 295                                 &sp->pgid, &sp->sid, &tty,
 296                                 &sp->utime, &sp->stime,
 297                                 &tasknice,
 298                                 &sp->start_time,
 299                                 &vsz,
 300                                 &rss
 301 # if ENABLE_FEATURE_TOP_SMP_PROCESS
 302                                 , &sp->last_seen_on_cpu
 303 # endif
 304                                 );
 305
 306                         if (n < 11)
 307                                 continue; /* bogus data, get next /proc/XXX */
 308 # if ENABLE_FEATURE_TOP_SMP_PROCESS
 309                         if (n < 11+15)
 310                                 sp->last_seen_on_cpu = 0;
 311 # endif
 312
 313                         /* vsz is in bytes and we want kb */
 314                         sp->vsz = vsz >> 10;
 315                         /* vsz is in bytes but rss is in *PAGES*! Can you believe that? */
 316                         sp->rss = rss << sp->shift_pages_to_kb;
 317                         sp->tty_major = (tty >> 8) & 0xfff;
 318                         sp->tty_minor = (tty & 0xff) | ((tty >> 12) & 0xfff00);
 319 #else
 320 /* This costs ~100 bytes more but makes top faster by 20%
 321  * If you run 10000 processes, this may be important for you */
 322                         sp->state[0] = cp[2];
 323                         cp += 4;
 324                         sp->ppid = fast_strtoul_10(&cp);
 325                         sp->pgid = fast_strtoul_10(&cp);
 326                         sp->sid = fast_strtoul_10(&cp);
 327                         tty = fast_strtoul_10(&cp);
 328                         sp->tty_major = (tty >> 8) & 0xfff;
 329                         sp->tty_minor = (tty & 0xff) | ((tty >> 12) & 0xfff00);
 330                         cp = skip_fields(cp, 6); /* tpgid, flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
 331                         sp->utime = fast_strtoul_10(&cp);
 332                         sp->stime = fast_strtoul_10(&cp);
 333                         cp = skip_fields(cp, 3); /* cutime, cstime, priority */
 334                         tasknice = fast_strtol_10(&cp);
 335                         cp = skip_fields(cp, 2); /* timeout, it_real_value */
 336                         sp->start_time = fast_strtoul_10(&cp);
 337                         /* vsz is in bytes and we want kb */
 338                         sp->vsz = fast_strtoul_10(&cp) >> 10;
 339                         /* vsz is in bytes but rss is in *PAGES*! Can you believe that? */
 340                         sp->rss = fast_strtoul_10(&cp) << sp->shift_pages_to_kb;
 341 # if ENABLE_FEATURE_TOP_SMP_PROCESS
 342                         /* (6): rss_rlim, start_code, end_code, start_stack, kstk_esp, kstk_eip */
 343                         /* (4): signal, blocked, sigignore, sigcatch */
 344                         /* (4): wchan, nswap, cnswap, exit_signal */
 345                         cp = skip_fields(cp, 14);
 346 //FIXME: is it safe to assume this field exists?
 347                         sp->last_seen_on_cpu = fast_strtoul_10(&cp);
 348 # endif
 349 #endif /* end of !ENABLE_FEATURE_TOP_SMP_PROCESS */
 350
 351 #if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
 352                         sp->niceness = tasknice;
 353 #endif
 354
 355                         if (sp->vsz == 0 && sp->state[0] != 'Z')
 356                                 sp->state[1] = 'W';
 357                         else
 358                                 sp->state[1] = ' ';
 359                         if (tasknice < 0)
 360                                 sp->state[2] = '<';
 361                         else if (tasknice) /* > 0 */
 362                                 sp->state[2] = 'N';
 363                         else
 364                                 sp->state[2] = ' ';
 365                 }
 366
 367 #if ENABLE_FEATURE_TOPMEM
 368                 if (flags & (PSSCAN_SMAPS)) {
 369                         FILE *file;
 370
 371                         strcpy(filename_tail, "smaps");
 372                         file = fopen_for_read(filename);
 373                         if (file) {
 374                                 while (fgets(buf, sizeof(buf), file)) {
 375                                         unsigned long sz;
 376                                         char *tp;
 377                                         char w;
 378 #define SCAN(str, name) \
 379         if (strncmp(buf, str, sizeof(str)-1) == 0) { \
 380                 tp = skip_whitespace(buf + sizeof(str)-1); \
 381                 sp->name += fast_strtoul_10(&tp); \
 382                 continue; \
 383         }
 384                                         SCAN("Shared_Clean:" , shared_clean );
 385                                         SCAN("Shared_Dirty:" , shared_dirty );
 386                                         SCAN("Private_Clean:", private_clean);
 387                                         SCAN("Private_Dirty:", private_dirty);
 388 #undef SCAN
 389                                         // f7d29000-f7d39000 rw-s ADR M:m OFS FILE
 390                                         tp = strchr(buf, '-');
 391                                         if (tp) {
 392                                                 *tp = ' ';
 393                                                 tp = buf;
 394                                                 sz = fast_strtoul_16(&tp); /* start */
 395                                                 sz = (fast_strtoul_16(&tp) - sz) >> 10; /* end - start */
 396                                                 // tp -> "rw-s" string
 397                                                 w = tp[1];
 398                                                 // skipping "rw-s ADR M:m OFS "
 399                                                 tp = skip_whitespace(skip_fields(tp, 4));
 400                                                 // filter out /dev/something (something != zero)
 401                                                 if (strncmp(tp, "/dev/", 5) != 0 || strcmp(tp, "/dev/zero\n") == 0) {
 402                                                         if (w == 'w') {
 403                                                                 sp->mapped_rw += sz;
 404                                                         } else if (w == '-') {
 405                                                                 sp->mapped_ro += sz;
 406                                                         }
 407                                                 }
 408 //else printf("DROPPING %s (%s)\n", buf, tp);
 409                                                 if (strcmp(tp, "[stack]\n") == 0)
 410                                                         sp->stack += sz;
 411                                         }
 412                                 }
 413                                 fclose(file);
 414                         }
 415                 }
 416 #endif /* TOPMEM */
 417 #if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
 418                 if (flags & PSSCAN_RUIDGID) {
 419                         FILE *file;
 420
 421                         strcpy(filename_tail, "status");
 422                         file = fopen_for_read(filename);
 423                         if (file) {
 424                                 while (fgets(buf, sizeof(buf), file)) {
 425                                         char *tp;
 426 #define SCAN_TWO(str, name, statement) \
 427         if (strncmp(buf, str, sizeof(str)-1) == 0) { \
 428                 tp = skip_whitespace(buf + sizeof(str)-1); \
 429                 sscanf(tp, "%u", &sp->name); \
 430                 statement; \
 431         }
 432                                         SCAN_TWO("Uid:", ruid, continue);
 433                                         SCAN_TWO("Gid:", rgid, break);
 434 #undef SCAN_TWO
 435                                 }
 436                                 fclose(file);
 437                         }
 438                 }
 439 #endif /* PS_ADDITIONAL_COLUMNS */
 440                 if (flags & PSSCAN_EXE) {
 441                         strcpy(filename_tail, "exe");
 442                         free(sp->exe);
 443                         sp->exe = xmalloc_readlink(filename);
 444                 }
 445                 /* Note: if /proc/PID/cmdline is empty,
 446                  * code below "breaks". Therefore it must be
 447                  * the last code to parse /proc/PID/xxx data
 448                  * (we used to have /proc/PID/exe parsing after it
 449                  * and were getting stale sp->exe).
 450                  */
 451 #if 0 /* PSSCAN_CMD is not used */
 452                 if (flags & (PSSCAN_CMD|PSSCAN_ARGV0)) {
 453                         free(sp->argv0);
 454                         sp->argv0 = NULL;
 455                         free(sp->cmd);
 456                         sp->cmd = NULL;
 457                         strcpy(filename_tail, "cmdline");
 458                         /* TODO: to get rid of size limits, read into malloc buf,
 459                          * then realloc it down to real size. */
 460                         n = read_to_buf(filename, buf);
 461                         if (n <= 0)
 462                                 break;
 463                         if (flags & PSSCAN_ARGV0)
 464                                 sp->argv0 = xstrdup(buf);
 465                         if (flags & PSSCAN_CMD) {
 466                                 do {
 467                                         n--;
 468                                         if ((unsigned char)(buf[n]) < ' ')
 469                                                 buf[n] = ' ';
 470                                 } while (n);
 471                                 sp->cmd = xstrdup(buf);
 472                         }
 473                 }
 474 #else
 475                 if (flags & (PSSCAN_ARGV0|PSSCAN_ARGVN)) {
 476                         free(sp->argv0);
 477                         sp->argv0 = NULL;
 478                         strcpy(filename_tail, "cmdline");
 479                         n = read_to_buf(filename, buf);
 480                         if (n <= 0)
 481                                 break;
 482                         if (flags & PSSCAN_ARGVN) {
 483                                 sp->argv_len = n;
 484                                 sp->argv0 = xmalloc(n + 1);
 485                                 memcpy(sp->argv0, buf, n + 1);
 486                                 /* sp->argv0[n] = '\0'; - buf has it */
 487                         } else {
 488                                 sp->argv_len = 0;
 489                                 sp->argv0 = xstrdup(buf);
 490                         }
 491                 }
 492 #endif
 493                 break;
 494         } /* for (;;) */
 495
 496         return sp;
 497 }
 498
 499 void FAST_FUNC read_cmdline(char *buf, int col, unsigned pid, const char *comm)
 500 {
 501         int sz;
 502         char filename[sizeof("/proc//cmdline") + sizeof(int)*3];
 503
 504         sprintf(filename, "/proc/%u/cmdline", pid);
 505         sz = open_read_close(filename, buf, col - 1);
 506         if (sz > 0) {
 507                 buf[sz] = '\0';
 508                 while (--sz >= 0 && buf[sz] == '\0')
 509                         continue;
 510                 do {
 511                         if ((unsigned char)(buf[sz]) < ' ')
 512                                 buf[sz] = ' ';
 513                 } while (--sz >= 0);
 514         } else {
 515                 snprintf(buf, col, "[%s]", comm);
 516         }
 517 }
 518
 519 /* from kernel:
 520         //             pid comm S ppid pgid sid tty_nr tty_pgrp flg
 521         sprintf(buffer,"%d (%s) %c %d  %d   %d  %d     %d       %lu %lu \
 522 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
 523 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %lu %lu %llu\n",
 524                 task->pid,
 525                 tcomm,
 526                 state,
 527                 ppid,
 528                 pgid,
 529                 sid,
 530                 tty_nr,
 531                 tty_pgrp,
 532                 task->flags,
 533                 min_flt,
 534                 cmin_flt,
 535                 maj_flt,
 536                 cmaj_flt,
 537                 cputime_to_clock_t(utime),
 538                 cputime_to_clock_t(stime),
 539                 cputime_to_clock_t(cutime),
 540                 cputime_to_clock_t(cstime),
 541                 priority,
 542                 nice,
 543                 num_threads,
 544                 // 0,
 545                 start_time,
 546                 vsize,
 547                 mm ? get_mm_rss(mm) : 0,
 548                 rsslim,
 549                 mm ? mm->start_code : 0,
 550                 mm ? mm->end_code : 0,
 551                 mm ? mm->start_stack : 0,
 552                 esp,
 553                 eip,
 554 the rest is some obsolete cruft
 555 */