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