LXR toybox/toys/posix/getconf.c

   1/* getconf.c - get configuration values
   2 *
   3 * Copyright 2017 Rob Landley <rob@landley.net>
   4 *
   5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/getconf.c
   6 *
   7 * Deviations from posix: no -v because nothing says what it should DO.
   8 * Added -l, what symbols should be included is a bit unclear.
   9 * Added -a, copied FSF behavior of assuming "/" if no path supplied.
  10
  11USE_GETCONF(NEWTOY(getconf, ">2al", TOYFLAG_USR|TOYFLAG_BIN))
  12
  13config GETCONF
  14  bool "getconf"
  15  default y
  16  help
  17    usage: getconf -a [PATH] | -l | NAME [PATH]
  18
  19    Get system configuration values. Values from pathconf(3) require a path.
  20
  21    -a  Show all (defaults to "/" if no path given)
  22    -l  List available value names (grouped by source)
  23*/
  24
  25#define FOR_getconf
  26#include "toys.h"
  27#include <limits.h>
  28
  29// This is missing on glibc (bionic has it).
  30#ifndef _SC_XOPEN_UUCP
  31#define _SC_XOPEN_UUCP -1
  32#endif
  33
  34#ifdef __APPLE__
  35// macOS doesn't have a bunch of stuff. The actual macOS getconf says
  36// "no such parameter", but -- unless proven otherwise -- it seems more useful
  37// for portability if we act like we understood but say "undefined"?
  38#define _SC_AVPHYS_PAGES -1
  39#define _SC_THREAD_ROBUST_PRIO_INHERIT -1
  40#define _SC_THREAD_ROBUST_PRIO_PROTECT -1
  41#define _SC_UIO_MAXIOV -1
  42#define _SC_V7_ILP32_OFF32 -1
  43#define _SC_V7_ILP32_OFFBIG -1
  44#define _SC_V7_LP64_OFF64 -1
  45#define _SC_V7_LPBIG_OFFBIG -1
  46#define _CS_V7_ENV -1
  47#endif
  48
  49struct config {
  50  char *name;
  51  long long value;
  52};
  53
  54// Lists of symbols getconf can query, broken down by whether we call sysconf(),
  55// confstr(), or output the macro value directly.
  56
  57// Probe the live system
  58static struct config sysconfs[] = {
  59  /* POSIX */
  60#define CONF(n) {"_POSIX_" #n,_SC_ ## n}
  61  CONF(ADVISORY_INFO), CONF(BARRIERS), CONF(ASYNCHRONOUS_IO),
  62  CONF(CLOCK_SELECTION), CONF(CPUTIME), CONF(FSYNC), CONF(IPV6),
  63  CONF(JOB_CONTROL), CONF(MAPPED_FILES), CONF(MEMLOCK), CONF(MEMLOCK_RANGE),
  64  CONF(MEMORY_PROTECTION), CONF(MESSAGE_PASSING), CONF(MONOTONIC_CLOCK),
  65  CONF(PRIORITY_SCHEDULING), CONF(RAW_SOCKETS), CONF(READER_WRITER_LOCKS),
  66  CONF(REALTIME_SIGNALS), CONF(REGEXP), CONF(SAVED_IDS), CONF(SEMAPHORES),
  67  CONF(SHARED_MEMORY_OBJECTS), CONF(SHELL), CONF(SPAWN), CONF(SPIN_LOCKS),
  68  CONF(SPORADIC_SERVER), CONF(SS_REPL_MAX), CONF(SYNCHRONIZED_IO),
  69  CONF(THREAD_ATTR_STACKADDR), CONF(THREAD_ATTR_STACKSIZE),
  70  CONF(THREAD_CPUTIME), CONF(THREAD_PRIO_INHERIT), CONF(THREAD_PRIO_PROTECT),
  71  CONF(THREAD_PRIORITY_SCHEDULING), CONF(THREAD_PROCESS_SHARED),
  72  CONF(THREAD_ROBUST_PRIO_INHERIT), CONF(THREAD_ROBUST_PRIO_PROTECT),
  73  CONF(THREAD_SAFE_FUNCTIONS), CONF(THREAD_SPORADIC_SERVER), CONF(THREADS),
  74  CONF(TIMEOUTS), CONF(TIMERS), CONF(TRACE), CONF(TRACE_EVENT_FILTER),
  75  CONF(TRACE_EVENT_NAME_MAX), CONF(TRACE_INHERIT), CONF(TRACE_LOG),
  76  CONF(TRACE_NAME_MAX), CONF(TRACE_SYS_MAX), CONF(TRACE_USER_EVENT_MAX),
  77  CONF(TYPED_MEMORY_OBJECTS), CONF(VERSION), CONF(V7_ILP32_OFF32),
  78  CONF(V7_ILP32_OFFBIG), CONF(V7_LP64_OFF64), CONF(V7_LPBIG_OFFBIG),
  79
  80  /* POSIX.2 */
  81#undef CONF
  82#define CONF(n) {"POSIX2_" #n,_SC_2_ ## n}
  83  CONF(C_BIND), CONF(C_DEV), CONF(CHAR_TERM), CONF(FORT_DEV), CONF(FORT_RUN),
  84  CONF(LOCALEDEF), CONF(PBS), CONF(PBS_ACCOUNTING), CONF(PBS_CHECKPOINT),
  85  CONF(PBS_LOCATE), CONF(PBS_MESSAGE), CONF(PBS_TRACK), CONF(SW_DEV),
  86  CONF(UPE), CONF(VERSION),
  87
  88  /* X/Open */
  89#undef CONF
  90#define CONF(n) {"_XOPEN_" #n,_SC_XOPEN_ ## n}
  91  CONF(CRYPT), CONF(ENH_I18N), CONF(REALTIME), CONF(REALTIME_THREADS),
  92  CONF(SHM), CONF(STREAMS), CONF(UNIX), CONF(UUCP), CONF(VERSION),
  93
  94  /* No obvious standard */
  95#undef CONF
  96#define CONF(n) {#n,_SC_ ## n}
  97  CONF(AIO_LISTIO_MAX), CONF(AIO_MAX), CONF(AIO_PRIO_DELTA_MAX), CONF(ARG_MAX),
  98  CONF(ATEXIT_MAX), CONF(BC_BASE_MAX), CONF(BC_DIM_MAX), CONF(BC_SCALE_MAX),
  99  CONF(BC_STRING_MAX), CONF(CHILD_MAX), CONF(CLK_TCK), CONF(COLL_WEIGHTS_MAX),
 100  CONF(DELAYTIMER_MAX), CONF(EXPR_NEST_MAX), CONF(HOST_NAME_MAX),
 101  CONF(IOV_MAX), CONF(LINE_MAX), CONF(LOGIN_NAME_MAX), CONF(NGROUPS_MAX),
 102  CONF(MQ_OPEN_MAX), CONF(MQ_PRIO_MAX), CONF(OPEN_MAX), CONF(PAGE_SIZE),
 103  CONF(PAGESIZE), CONF(RAW_SOCKETS), CONF(RE_DUP_MAX), CONF(RTSIG_MAX),
 104  CONF(SEM_NSEMS_MAX), CONF(SEM_VALUE_MAX), CONF(SIGQUEUE_MAX),
 105  CONF(STREAM_MAX), CONF(SYMLOOP_MAX), CONF(TIMER_MAX), CONF(TTY_NAME_MAX),
 106  CONF(TZNAME_MAX), CONF(UIO_MAXIOV),
 107
 108  /* Names that just don't match the symbol, do it by hand */
 109  {"_AVPHYS_PAGES", _SC_AVPHYS_PAGES}, {"_PHYS_PAGES", _SC_PHYS_PAGES},
 110  {"_NPROCESSORS_CONF", _SC_NPROCESSORS_CONF},
 111  {"_NPROCESSORS_ONLN", _SC_NPROCESSORS_ONLN},
 112
 113  /* There's a weird "PTHREAD" vs "THREAD" mismatch here. */
 114  {"PTHREAD_DESTRUCTOR_ITERATIONS", _SC_THREAD_DESTRUCTOR_ITERATIONS},
 115  {"PTHREAD_KEYS_MAX", _SC_THREAD_KEYS_MAX},
 116  {"PTHREAD_STACK_MIN", _SC_THREAD_STACK_MIN},
 117  {"PTHREAD_THREADS_MAX", _SC_THREAD_THREADS_MAX},
 118};
 119
 120// Probe the live system with a path
 121static struct config pathconfs[] = {
 122#undef CONF
 123#define CONF(n) {#n,_PC_ ## n}
 124  CONF(ASYNC_IO), CONF(CHOWN_RESTRICTED), CONF(FILESIZEBITS), CONF(LINK_MAX),
 125  CONF(MAX_CANON), CONF(MAX_INPUT), CONF(NAME_MAX), CONF(NO_TRUNC),
 126  CONF(PATH_MAX), CONF(PIPE_BUF), CONF(PRIO_IO), CONF(SYMLINK_MAX),
 127  CONF(SYNC_IO),
 128  {"_POSIX_VDISABLE", _PC_VDISABLE},
 129};
 130
 131// Strings out of a header
 132static struct config confstrs[] = {
 133#undef CONF
 134#define CONF(n) {#n,_CS_ ## n}
 135  CONF(PATH), CONF(V7_ENV)
 136};
 137
 138// Integers out of a header
 139static struct config limits[] = {
 140#undef CONF
 141#define CONF(n) {#n,n}
 142  CONF(_POSIX_AIO_LISTIO_MAX), CONF(_POSIX_AIO_MAX), CONF(_POSIX_ARG_MAX),
 143  CONF(_POSIX_CHILD_MAX), CONF(_POSIX_DELAYTIMER_MAX),
 144  CONF(_POSIX_HOST_NAME_MAX), CONF(_POSIX_LINK_MAX),
 145  CONF(_POSIX_LOGIN_NAME_MAX), CONF(_POSIX_MAX_CANON),
 146  CONF(_POSIX_MAX_INPUT), CONF(_POSIX_NAME_MAX), CONF(_POSIX_NGROUPS_MAX),
 147  CONF(_POSIX_OPEN_MAX), CONF(_POSIX_PATH_MAX), CONF(_POSIX_PIPE_BUF),
 148  CONF(_POSIX_RE_DUP_MAX), CONF(_POSIX_RTSIG_MAX), CONF(_POSIX_SEM_NSEMS_MAX),
 149  CONF(_POSIX_SEM_VALUE_MAX), CONF(_POSIX_SIGQUEUE_MAX), CONF(_POSIX_SSIZE_MAX),
 150  CONF(_POSIX_STREAM_MAX), CONF(_POSIX_SYMLINK_MAX), CONF(_POSIX_SYMLOOP_MAX),
 151  CONF(_POSIX_THREAD_DESTRUCTOR_ITERATIONS), CONF(_POSIX_THREAD_KEYS_MAX),
 152  CONF(_POSIX_THREAD_THREADS_MAX), CONF(_POSIX_TIMER_MAX),
 153  CONF(_POSIX_TTY_NAME_MAX), CONF(_POSIX_TZNAME_MAX),
 154  CONF(CHAR_MAX), CONF(CHAR_MIN), CONF(INT_MAX), CONF(INT_MIN), CONF(SCHAR_MAX),
 155  CONF(SCHAR_MIN), CONF(SHRT_MAX), CONF(SHRT_MIN), CONF(SSIZE_MAX),
 156  CONF(UCHAR_MAX), CONF(UINT_MAX), CONF(ULONG_MAX), CONF(USHRT_MAX),
 157  CONF(CHAR_BIT),
 158  /* Not available in glibc without _GNU_SOURCE. */
 159  {"LONG_BIT", 8*sizeof(long)},
 160  {"WORD_BIT", 8*sizeof(int)},
 161#undef CONF
 162#define CONF(n) {#n,_ ## n}
 163  CONF(POSIX2_BC_BASE_MAX), CONF(POSIX2_BC_DIM_MAX),
 164  CONF(POSIX2_BC_SCALE_MAX), CONF(POSIX2_BC_STRING_MAX),
 165  CONF(POSIX2_CHARCLASS_NAME_MAX), CONF(POSIX2_COLL_WEIGHTS_MAX),
 166  CONF(POSIX2_EXPR_NEST_MAX), CONF(POSIX2_LINE_MAX), CONF(POSIX2_RE_DUP_MAX),
 167};
 168
 169// Names we need to handle ourselves (default to blank but shouldn't error)
 170static struct config others[] = {
 171  {"LFS_CFLAGS", 0}, {"LFS_LDFLAGS", 0}, {"LFS_LIBS", 0}
 172};
 173
 174static void show_conf(int i, struct config *c, const char *path)
 175{
 176  if (i<2) {
 177    long l = i ? pathconf(path, c->value) : sysconf(c->value);
 178
 179    if (l == -1) puts("undefined");
 180    else printf("%ld\n", l);
 181  } else if (i==2) {
 182    confstr(c->value, toybuf, sizeof(toybuf));
 183    puts(toybuf);
 184  } else if (i==3) printf("%lld\n", c->value);
 185  // LFS_CFLAGS on 32 bit should enable Large File Support for kernel builds
 186  else puts(sizeof(long)==4 && !strcmp(c->name, "LFS_CFLAGS") ?
 187    "-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64" : "");
 188}
 189
 190void getconf_main(void)
 191{
 192  struct config *configs[] = {sysconfs, pathconfs, confstrs, limits, others},
 193    *c = NULL;
 194  int i, j, lens[] = {ARRAY_LEN(sysconfs), ARRAY_LEN(pathconfs),
 195    ARRAY_LEN(confstrs), ARRAY_LEN(limits), ARRAY_LEN(others)};
 196  char *name, *path = (toys.optc==2) ? toys.optargs[1] : "/",
 197    *config_names[] = {"sysconf(3)", "pathconf(3)", "confstr(3)",
 198    "<limits.h>", "Misc"};
 199
 200  if (toys.optflags&FLAG_a) {
 201    for (i = 0; i<5; i++) {
 202      for (j = 0; j<lens[i]; j++) {
 203        c = &configs[i][j];
 204        printf("%-34s ", c->name);
 205        show_conf(i, c, path);
 206      }
 207    }
 208    return;
 209  }
 210
 211  if (toys.optflags&FLAG_l) {
 212    for (i = 0; i<5; i++) {
 213      printf("%s\n", config_names[i]);
 214      for (j = 0; j<lens[i]; j++) printf("  %s\n", configs[i][j].name);
 215    }
 216    return;
 217  }
 218
 219  if (toys.optc<1) help_exit(0);
 220  name = *toys.optargs;
 221
 222  // Workaround for autogen using CS_PATH instead of PATH
 223  if (!strcmp("CS_PATH", name)) name += 3;
 224
 225  // Find the config.
 226  for (i = j = 0; ; j++) {
 227    if (j==lens[i]) j = 0, i++;
 228    if (i==5) error_exit("bad '%s'", name);
 229    c = &configs[i][j];
 230    if (!strcmp(c->name, name)) break;
 231  }
 232
 233  // Check that we do/don't have the extra path argument.
 234  if (i==1) {
 235    if (toys.optc!=2) help_exit("%s needs a path", name);
 236  } else if (toys.optc!=1) help_exit("%s does not take a path", name);
 237
 238  show_conf(i, c, path);
 239}
 240