libc-top-half/musl/src/conf/sysconf.c

   1 #include <unistd.h>
   2 #include <limits.h>
   3 #include <errno.h>
   4 #include <sys/resource.h>
   5 #ifdef __wasilibc_unmodified_upstream // WASI has no realtime signals
   6 #include <signal.h>
   7 #endif
   8 #include <sys/sysinfo.h>
   9 #include "syscall.h"
  10 #include "libc.h"
  11
  12 #define JT(x) (-256|(x))
  13 #define VER JT(1)
  14 #define JT_ARG_MAX JT(2)
  15 #ifdef __wasilibc_unmodified_upstream // WASI has no mq
  16 #define JT_MQ_PRIO_MAX JT(3)
  17 #endif
  18 #define JT_PAGE_SIZE JT(4)
  19 #ifdef __wasilibc_unmodified_upstream // WASI has no semaphores
  20 #define JT_SEM_VALUE_MAX JT(5)
  21 #endif
  22 #define JT_NPROCESSORS_CONF JT(6)
  23 #define JT_NPROCESSORS_ONLN JT(7)
  24 #define JT_PHYS_PAGES JT(8)
  25 #define JT_AVPHYS_PAGES JT(9)
  26 #define JT_ZERO JT(10)
  27 #define JT_DELAYTIMER_MAX JT(11)
  28
  29 #define RLIM(x) (-32768|(RLIMIT_ ## x))
  30
  31 long sysconf(int name)
  32 {
  33         static const short values[] = {
  34                 [_SC_ARG_MAX] = JT_ARG_MAX,
  35 #ifdef __wasilibc_unmodified_upstream // WASI has no processes
  36                 [_SC_CHILD_MAX] = RLIM(NPROC),
  37 #else
  38                 // Not supported on wasi.
  39                 [_SC_CHILD_MAX] = -1,
  40 #endif
  41                 [_SC_CLK_TCK] = 100,
  42                 [_SC_NGROUPS_MAX] = 32,
  43 #ifdef __wasilibc_unmodified_upstream // WASI has no rlimit
  44                 [_SC_OPEN_MAX] = RLIM(NOFILE),
  45 #else
  46                 // Rlimit is not supported on wasi.
  47                 [_SC_OPEN_MAX] = -1,
  48 #endif
  49
  50                 [_SC_STREAM_MAX] = -1,
  51                 [_SC_TZNAME_MAX] = TZNAME_MAX,
  52                 [_SC_JOB_CONTROL] = 1,
  53                 [_SC_SAVED_IDS] = 1,
  54                 [_SC_REALTIME_SIGNALS] = VER,
  55                 [_SC_PRIORITY_SCHEDULING] = -1,
  56                 [_SC_TIMERS] = VER,
  57                 [_SC_ASYNCHRONOUS_IO] = VER,
  58                 [_SC_PRIORITIZED_IO] = -1,
  59                 [_SC_SYNCHRONIZED_IO] = -1,
  60                 [_SC_FSYNC] = VER,
  61                 [_SC_MAPPED_FILES] = VER,
  62                 [_SC_MEMLOCK] = VER,
  63                 [_SC_MEMLOCK_RANGE] = VER,
  64                 [_SC_MEMORY_PROTECTION] = VER,
  65                 [_SC_MESSAGE_PASSING] = VER,
  66                 [_SC_SEMAPHORES] = VER,
  67                 [_SC_SHARED_MEMORY_OBJECTS] = VER,
  68                 [_SC_AIO_LISTIO_MAX] = -1,
  69                 [_SC_AIO_MAX] = -1,
  70                 [_SC_AIO_PRIO_DELTA_MAX] = JT_ZERO, /* ?? */
  71                 [_SC_DELAYTIMER_MAX] = JT_DELAYTIMER_MAX,
  72 #ifdef __wasilibc_unmodified_upstream // WASI has no mq
  73                 [_SC_MQ_OPEN_MAX] = -1,
  74                 [_SC_MQ_PRIO_MAX] = JT_MQ_PRIO_MAX,
  75 #endif
  76                 [_SC_VERSION] = VER,
  77                 [_SC_PAGE_SIZE] = JT_PAGE_SIZE,
  78 #ifdef __wasilibc_unmodified_upstream // WASI has no realtime signals
  79                 [_SC_RTSIG_MAX] = _NSIG - 1 - 31 - 3,
  80 #else
  81                 // Not supported on wasi.
  82                 [_SC_RTSIG_MAX] = -1,
  83 #endif
  84 #ifdef __wasilibc_unmodified_upstream // WASI has no semaphores
  85                 [_SC_SEM_NSEMS_MAX] = SEM_NSEMS_MAX,
  86                 [_SC_SEM_VALUE_MAX] = JT_SEM_VALUE_MAX,
  87 #else
  88                 [_SC_SEM_NSEMS_MAX] = -1,
  89                 [_SC_SEM_VALUE_MAX] = -1,
  90 #endif
  91                 [_SC_SIGQUEUE_MAX] = -1,
  92                 [_SC_TIMER_MAX] = -1,
  93 #ifdef __wasilibc_unmodified_upstream // WASI has no shell commands
  94                 [_SC_BC_BASE_MAX] = _POSIX2_BC_BASE_MAX,
  95                 [_SC_BC_DIM_MAX] = _POSIX2_BC_DIM_MAX,
  96                 [_SC_BC_SCALE_MAX] = _POSIX2_BC_SCALE_MAX,
  97                 [_SC_BC_STRING_MAX] = _POSIX2_BC_STRING_MAX,
  98 #else
  99                 [_SC_BC_BASE_MAX] = -1,
 100                 [_SC_BC_DIM_MAX] = -1,
 101                 [_SC_BC_SCALE_MAX] = -1,
 102                 [_SC_BC_STRING_MAX] = -1,
 103 #endif
 104                 [_SC_COLL_WEIGHTS_MAX] = COLL_WEIGHTS_MAX,
 105                 [_SC_EXPR_NEST_MAX] = -1,
 106                 [_SC_LINE_MAX] = -1,
 107                 [_SC_RE_DUP_MAX] = RE_DUP_MAX,
 108                 [_SC_2_VERSION] = VER,
 109                 [_SC_2_C_BIND] = VER,
 110                 [_SC_2_C_DEV] = -1,
 111                 [_SC_2_FORT_DEV] = -1,
 112                 [_SC_2_FORT_RUN] = -1,
 113                 [_SC_2_SW_DEV] = -1,
 114                 [_SC_2_LOCALEDEF] = -1,
 115                 [_SC_IOV_MAX] = IOV_MAX,
 116                 [_SC_THREADS] = VER,
 117                 [_SC_THREAD_SAFE_FUNCTIONS] = VER,
 118                 [_SC_GETGR_R_SIZE_MAX] = -1,
 119                 [_SC_GETPW_R_SIZE_MAX] = -1,
 120                 [_SC_LOGIN_NAME_MAX] = 256,
 121                 [_SC_TTY_NAME_MAX] = TTY_NAME_MAX,
 122 #if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
 123                 [_SC_THREAD_DESTRUCTOR_ITERATIONS] = PTHREAD_DESTRUCTOR_ITERATIONS,
 124                 [_SC_THREAD_KEYS_MAX] = PTHREAD_KEYS_MAX,
 125                 [_SC_THREAD_STACK_MIN] = PTHREAD_STACK_MIN,
 126 #else
 127                 [_SC_THREAD_DESTRUCTOR_ITERATIONS] = -1,
 128                 [_SC_THREAD_KEYS_MAX] = -1,
 129                 [_SC_THREAD_STACK_MIN] = -1,
 130 #endif
 131                 [_SC_THREAD_THREADS_MAX] = -1,
 132                 [_SC_THREAD_ATTR_STACKADDR] = VER,
 133                 [_SC_THREAD_ATTR_STACKSIZE] = VER,
 134                 [_SC_THREAD_PRIORITY_SCHEDULING] = VER,
 135                 [_SC_THREAD_PRIO_INHERIT] = -1,
 136                 [_SC_THREAD_PRIO_PROTECT] = -1,
 137                 [_SC_THREAD_PROCESS_SHARED] = VER,
 138                 [_SC_NPROCESSORS_CONF] = JT_NPROCESSORS_CONF,
 139                 [_SC_NPROCESSORS_ONLN] = JT_NPROCESSORS_ONLN,
 140                 [_SC_PHYS_PAGES] = JT_PHYS_PAGES,
 141                 [_SC_AVPHYS_PAGES] = JT_AVPHYS_PAGES,
 142                 [_SC_ATEXIT_MAX] = -1,
 143                 [_SC_PASS_MAX] = -1,
 144                 [_SC_XOPEN_VERSION] = _XOPEN_VERSION,
 145                 [_SC_XOPEN_XCU_VERSION] = _XOPEN_VERSION,
 146                 [_SC_XOPEN_UNIX] = 1,
 147                 [_SC_XOPEN_CRYPT] = -1,
 148                 [_SC_XOPEN_ENH_I18N] = 1,
 149                 [_SC_XOPEN_SHM] = 1,
 150                 [_SC_2_CHAR_TERM] = -1,
 151                 [_SC_2_UPE] = -1,
 152                 [_SC_XOPEN_XPG2] = -1,
 153                 [_SC_XOPEN_XPG3] = -1,
 154                 [_SC_XOPEN_XPG4] = -1,
 155                 [_SC_NZERO] = NZERO,
 156                 [_SC_XBS5_ILP32_OFF32] = -1,
 157                 [_SC_XBS5_ILP32_OFFBIG] = sizeof(long)==4 ? 1 : -1,
 158                 [_SC_XBS5_LP64_OFF64] = sizeof(long)==8 ? 1 : -1,
 159                 [_SC_XBS5_LPBIG_OFFBIG] = -1,
 160                 [_SC_XOPEN_LEGACY] = -1,
 161                 [_SC_XOPEN_REALTIME] = -1,
 162                 [_SC_XOPEN_REALTIME_THREADS] = -1,
 163                 [_SC_ADVISORY_INFO] = VER,
 164                 [_SC_BARRIERS] = VER,
 165                 [_SC_CLOCK_SELECTION] = VER,
 166                 [_SC_CPUTIME] = VER,
 167                 [_SC_THREAD_CPUTIME] = VER,
 168                 [_SC_MONOTONIC_CLOCK] = VER,
 169                 [_SC_READER_WRITER_LOCKS] = VER,
 170                 [_SC_SPIN_LOCKS] = VER,
 171                 [_SC_REGEXP] = 1,
 172                 [_SC_SHELL] = 1,
 173                 [_SC_SPAWN] = VER,
 174                 [_SC_SPORADIC_SERVER] = -1,
 175                 [_SC_THREAD_SPORADIC_SERVER] = -1,
 176                 [_SC_TIMEOUTS] = VER,
 177                 [_SC_TYPED_MEMORY_OBJECTS] = -1,
 178                 [_SC_2_PBS] = -1,
 179                 [_SC_2_PBS_ACCOUNTING] = -1,
 180                 [_SC_2_PBS_LOCATE] = -1,
 181                 [_SC_2_PBS_MESSAGE] = -1,
 182                 [_SC_2_PBS_TRACK] = -1,
 183                 [_SC_SYMLOOP_MAX] = SYMLOOP_MAX,
 184                 [_SC_STREAMS] = JT_ZERO,
 185                 [_SC_2_PBS_CHECKPOINT] = -1,
 186                 [_SC_V6_ILP32_OFF32] = -1,
 187                 [_SC_V6_ILP32_OFFBIG] = sizeof(long)==4 ? 1 : -1,
 188                 [_SC_V6_LP64_OFF64] = sizeof(long)==8 ? 1 : -1,
 189                 [_SC_V6_LPBIG_OFFBIG] = -1,
 190                 [_SC_HOST_NAME_MAX] = HOST_NAME_MAX,
 191                 [_SC_TRACE] = -1,
 192                 [_SC_TRACE_EVENT_FILTER] = -1,
 193                 [_SC_TRACE_INHERIT] = -1,
 194                 [_SC_TRACE_LOG] = -1,
 195
 196                 [_SC_IPV6] = VER,
 197                 [_SC_RAW_SOCKETS] = VER,
 198                 [_SC_V7_ILP32_OFF32] = -1,
 199                 [_SC_V7_ILP32_OFFBIG] = sizeof(long)==4 ? 1 : -1,
 200                 [_SC_V7_LP64_OFF64] = sizeof(long)==8 ? 1 : -1,
 201                 [_SC_V7_LPBIG_OFFBIG] = -1,
 202                 [_SC_SS_REPL_MAX] = -1,
 203                 [_SC_TRACE_EVENT_NAME_MAX] = -1,
 204                 [_SC_TRACE_NAME_MAX] = -1,
 205                 [_SC_TRACE_SYS_MAX] = -1,
 206                 [_SC_TRACE_USER_EVENT_MAX] = -1,
 207                 [_SC_XOPEN_STREAMS] = JT_ZERO,
 208                 [_SC_THREAD_ROBUST_PRIO_INHERIT] = -1,
 209                 [_SC_THREAD_ROBUST_PRIO_PROTECT] = -1,
 210         };
 211
 212         if (name >= sizeof(values)/sizeof(values[0]) || !values[name]) {
 213                 errno = EINVAL;
 214                 return -1;
 215         } else if (values[name] >= -1) {
 216                 return values[name];
 217         } else if (values[name] < -256) {
 218 #ifdef __wasilibc_unmodified_upstream // WASI has no getrlimit
 219                 struct rlimit lim;
 220                 getrlimit(values[name]&16383, &lim);
 221                 if (lim.rlim_cur == RLIM_INFINITY)
 222                         return -1;
 223                 return lim.rlim_cur > LONG_MAX ? LONG_MAX : lim.rlim_cur;
 224 #else
 225                 // Not supported on wasi.
 226                 errno = EINVAL;
 227                 return -1;
 228 #endif
 229         }
 230
 231         switch ((unsigned char)values[name]) {
 232         case VER & 255:
 233                 return _POSIX_VERSION;
 234         case JT_ARG_MAX & 255:
 235                 return ARG_MAX;
 236 #ifdef __wasilibc_unmodified_upstream // WASI has no mq
 237         case JT_MQ_PRIO_MAX & 255:
 238                 return MQ_PRIO_MAX;
 239 #endif
 240         case JT_PAGE_SIZE & 255:
 241                 return PAGE_SIZE;
 242 #ifdef __wasilibc_unmodified_upstream // WASI has no semaphores
 243         case JT_SEM_VALUE_MAX & 255:
 244                 return SEM_VALUE_MAX;
 245 #endif
 246         case JT_DELAYTIMER_MAX & 255:
 247                 return DELAYTIMER_MAX;
 248         case JT_NPROCESSORS_CONF & 255:
 249         case JT_NPROCESSORS_ONLN & 255: ;
 250 #if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
 251                 unsigned char set[128] = {1};
 252                 int i, cnt;
 253                 __syscall(SYS_sched_getaffinity, 0, sizeof set, set);
 254                 for (i=cnt=0; i<sizeof set; i++)
 255                         for (; set[i]; set[i]&=set[i]-1, cnt++);
 256                 return cnt;
 257 #else
 258                 // With no thread support, just say there's 1 processor.
 259                 return 1;
 260 #endif
 261 #ifdef __wasilibc_unmodified_upstream // WASI has no sysinfo
 262         case JT_PHYS_PAGES & 255:
 263         case JT_AVPHYS_PAGES & 255: ;
 264                 unsigned long long mem;
 265                 struct sysinfo si;
 266                 __lsysinfo(&si);
 267                 if (!si.mem_unit) si.mem_unit = 1;
 268                 if (name==_SC_PHYS_PAGES) mem = si.totalram;
 269                 else mem = si.freeram + si.bufferram;
 270                 mem *= si.mem_unit;
 271                 mem /= PAGE_SIZE;
 272                 return (mem > LONG_MAX) ? LONG_MAX : mem;
 273 #endif
 274         case JT_ZERO & 255:
 275                 return 0;
 276         }
 277         return values[name];
 278 }