winsup/utils/getconf.c

   1 /*-
   2  * Copyright (c) 1996, 1998 The NetBSD Foundation, Inc.
   3  * Copyright (c) 2011 Red Hat, Inc.
   4  * All rights reserved.
   5  *
   6  * This code is derived from software contributed to The NetBSD Foundation
   7  * by J.T. Conklin.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include <error.h>
  32 #include <errno.h>
  33 #include <limits.h>
  34 #include <locale.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <unistd.h>
  38 #include <string.h>
  39
  40 struct conf_variable
  41 {
  42   const char *name;
  43   enum { SYSCONF, CONFSTR, PATHCONF, CONSTANT } type;
  44   long long value;
  45 };
  46
  47 static const struct conf_variable conf_table[] =
  48 {
  49   /* Symbolic constants from confstr() */
  50   { "PATH",                             CONFSTR,        _CS_PATH        },
  51   { "POSIX_V7_ILP32_OFF32_CFLAGS",      CONFSTR,        _CS_POSIX_V7_ILP32_OFF32_CFLAGS },
  52   { "POSIX_V7_ILP32_OFF32_LDFLAGS",     CONFSTR,        _CS_POSIX_V7_ILP32_OFF32_LDFLAGS        },
  53   { "POSIX_V7_ILP32_OFF32_LIBS",        CONFSTR,        _CS_POSIX_V7_ILP32_OFF32_LIBS   },
  54   { "POSIX_V7_ILP32_OFFBIG_CFLAGS",     CONFSTR,        _CS_POSIX_V7_ILP32_OFFBIG_CFLAGS        },
  55   { "POSIX_V7_ILP32_OFFBIG_LDFLAGS",    CONFSTR,        _CS_POSIX_V7_ILP32_OFFBIG_LDFLAGS       },
  56   { "POSIX_V7_ILP32_OFFBIG_LIBS",       CONFSTR,        _CS_POSIX_V7_ILP32_OFFBIG_LIBS  },
  57   { "POSIX_V7_LP64_OFF64_CFLAGS",       CONFSTR,        _CS_POSIX_V7_LP64_OFF64_CFLAGS  },
  58   { "POSIX_V7_LP64_OFF64_LDFLAGS",      CONFSTR,        _CS_POSIX_V7_LP64_OFF64_LDFLAGS },
  59   { "POSIX_V7_LP64_OFF64_LIBS",         CONFSTR,        _CS_POSIX_V7_LP64_OFF64_LIBS    },
  60   { "POSIX_V7_LPBIG_OFFBIG_CFLAGS",     CONFSTR,        _CS_POSIX_V7_LPBIG_OFFBIG_CFLAGS        },
  61   { "POSIX_V7_LPBIG_OFFBIG_LDFLAGS",    CONFSTR,        _CS_POSIX_V7_LPBIG_OFFBIG_LDFLAGS       },
  62   { "POSIX_V7_LPBIG_OFFBIG_LIBS",       CONFSTR,        _CS_POSIX_V7_LPBIG_OFFBIG_LIBS  },
  63   { "POSIX_V7_THREADS_CFLAGS",          CONFSTR,        _CS_POSIX_V7_THREADS_CFLAGS     },
  64   { "POSIX_V7_THREADS_LDFLAGS",         CONFSTR,        _CS_POSIX_V7_THREADS_LDFLAGS    },
  65   { "POSIX_V7_WIDTH_RESTRICTED_ENVS",   CONFSTR,        _CS_POSIX_V7_WIDTH_RESTRICTED_ENVS      },
  66   { "POSIX_V6_ILP32_OFF32_CFLAGS",      CONFSTR,        _CS_POSIX_V6_ILP32_OFF32_CFLAGS },
  67   { "POSIX_V6_ILP32_OFF32_LDFLAGS",     CONFSTR,        _CS_POSIX_V6_ILP32_OFF32_LDFLAGS        },
  68   { "POSIX_V6_ILP32_OFF32_LIBS",        CONFSTR,        _CS_POSIX_V6_ILP32_OFF32_LIBS   },
  69   { "POSIX_V6_ILP32_OFFBIG_CFLAGS",     CONFSTR,        _CS_POSIX_V6_ILP32_OFFBIG_CFLAGS        },
  70   { "POSIX_V6_ILP32_OFFBIG_LDFLAGS",    CONFSTR,        _CS_POSIX_V6_ILP32_OFFBIG_LDFLAGS       },
  71   { "POSIX_V6_ILP32_OFFBIG_LIBS",       CONFSTR,        _CS_POSIX_V6_ILP32_OFFBIG_LIBS  },
  72   { "POSIX_V6_LP64_OFF64_CFLAGS",       CONFSTR,        _CS_POSIX_V6_LP64_OFF64_CFLAGS  },
  73   { "POSIX_V6_LP64_OFF64_LDFLAGS",      CONFSTR,        _CS_POSIX_V6_LP64_OFF64_LDFLAGS },
  74   { "POSIX_V6_LP64_OFF64_LIBS",         CONFSTR,        _CS_POSIX_V6_LP64_OFF64_LIBS    },
  75   { "POSIX_V6_LPBIG_OFFBIG_CFLAGS",     CONFSTR,        _CS_POSIX_V6_LPBIG_OFFBIG_CFLAGS        },
  76   { "POSIX_V6_LPBIG_OFFBIG_LDFLAGS",    CONFSTR,        _CS_POSIX_V6_LPBIG_OFFBIG_LDFLAGS       },
  77   { "POSIX_V6_LPBIG_OFFBIG_LIBS",       CONFSTR,        _CS_POSIX_V6_LPBIG_OFFBIG_LIBS  },
  78   { "POSIX_V6_WIDTH_RESTRICTED_ENVS",   CONFSTR,        _CS_POSIX_V6_WIDTH_RESTRICTED_ENVS      },
  79   { "XBS5_ILP32_OFF32_CFLAGS",          CONFSTR,        _CS_XBS5_ILP32_OFF32_CFLAGS     },
  80   { "XBS5_ILP32_OFF32_LDFLAGS",         CONFSTR,        _CS_XBS5_ILP32_OFF32_LDFLAGS    },
  81   { "XBS5_ILP32_OFF32_LIBS",            CONFSTR,        _CS_XBS5_ILP32_OFF32_LIBS       },
  82   { "XBS5_ILP32_OFF32_LINTFLAGS",       CONFSTR,        _CS_XBS5_ILP32_OFF32_LINTFLAGS  },
  83   { "XBS5_ILP32_OFFBIG_CFLAGS",         CONFSTR,        _CS_XBS5_ILP32_OFFBIG_CFLAGS    },
  84   { "XBS5_ILP32_OFFBIG_LDFLAGS",        CONFSTR,        _CS_XBS5_ILP32_OFFBIG_LDFLAGS   },
  85   { "XBS5_ILP32_OFFBIG_LIBS",           CONFSTR,        _CS_XBS5_ILP32_OFFBIG_LIBS      },
  86   { "XBS5_ILP32_OFFBIG_LINTFLAGS",      CONFSTR,        _CS_XBS5_ILP32_OFFBIG_LINTFLAGS },
  87   { "XBS5_LP64_OFF64_CFLAGS",           CONFSTR,        _CS_XBS5_LP64_OFF64_CFLAGS      },
  88   { "XBS5_LP64_OFF64_LDFLAGS",          CONFSTR,        _CS_XBS5_LP64_OFF64_LDFLAGS     },
  89   { "XBS5_LP64_OFF64_LIBS",             CONFSTR,        _CS_XBS5_LP64_OFF64_LIBS        },
  90   { "XBS5_LP64_OFF64_LINTFLAGS",        CONFSTR,        _CS_XBS5_LP64_OFF64_LINTFLAGS   },
  91   { "XBS5_LPBIG_OFFBIG_CFLAGS",         CONFSTR,        _CS_XBS5_LPBIG_OFFBIG_CFLAGS    },
  92   { "XBS5_LPBIG_OFFBIG_LDFLAGS",        CONFSTR,        _CS_XBS5_LPBIG_OFFBIG_LDFLAGS   },
  93   { "XBS5_LPBIG_OFFBIG_LIBS",           CONFSTR,        _CS_XBS5_LPBIG_OFFBIG_LIBS      },
  94   { "XBS5_LPBIG_OFFBIG_LINTFLAGS",      CONFSTR,        _CS_XBS5_LPBIG_OFFBIG_LINTFLAGS },
  95   { "XBS5_WIDTH_RESTRICTED_ENVS",       CONFSTR,        _CS_XBS5_WIDTH_RESTRICTED_ENVS  },
  96   { "V7_ENV",                           CONFSTR,        _CS_V7_ENV      },
  97   { "V6_ENV",                           CONFSTR,        _CS_V6_ENV      },
  98
  99   /* Symbolic constants from <limits.h> */
 100   { "_POSIX_AIO_LISTIO_MAX",            CONSTANT,       _POSIX_AIO_LISTIO_MAX   },
 101   { "_POSIX_AIO_MAX",                   CONSTANT,       _POSIX_AIO_MAX          },
 102   { "_POSIX_ARG_MAX",                   CONSTANT,       _POSIX_ARG_MAX          },
 103   { "_POSIX_CHILD_MAX",                 CONSTANT,       _POSIX_CHILD_MAX        },
 104   { "_POSIX_CLOCKRES_MIN",              CONSTANT,       _POSIX_CLOCKRES_MIN     },
 105   { "_POSIX_DELAYTIMER_MAX",            CONSTANT,       _POSIX_DELAYTIMER_MAX   },
 106   { "_POSIX_HOST_NAME_MAX",             CONSTANT,       _POSIX_HOST_NAME_MAX    },
 107   { "_POSIX_LINK_MAX",                  CONSTANT,       _POSIX_LINK_MAX         },
 108   { "_POSIX_LOGIN_NAME_MAX",            CONSTANT,       _POSIX_LOGIN_NAME_MAX   },
 109   { "_POSIX_MAX_CANON",                 CONSTANT,       _POSIX_MAX_CANON        },
 110   { "_POSIX_MAX_INPUT",                 CONSTANT,       _POSIX_MAX_INPUT        },
 111   { "_POSIX_MQ_OPEN_MAX",               CONSTANT,       _POSIX_MQ_OPEN_MAX      },
 112   { "_POSIX_MQ_PRIO_MAX",               CONSTANT,       _POSIX_MQ_PRIO_MAX      },
 113   { "_POSIX_NAME_MAX",                  CONSTANT,       _POSIX_NAME_MAX         },
 114   { "_POSIX_NGROUPS_MAX",               CONSTANT,       _POSIX_NGROUPS_MAX      },
 115   { "_POSIX_OPEN_MAX",                  CONSTANT,       _POSIX_OPEN_MAX         },
 116   { "_POSIX_PATH_MAX",                  CONSTANT,       _POSIX_PATH_MAX         },
 117   { "_POSIX_PIPE_BUF",                  CONSTANT,       _POSIX_PIPE_BUF         },
 118   { "_POSIX_RE_DUP_MAX",                CONSTANT,       _POSIX_RE_DUP_MAX       },
 119   { "_POSIX_RTSIG_MAX",                 CONSTANT,       _POSIX_RTSIG_MAX        },
 120   { "_POSIX_SEM_NSEMS_MAX",             CONSTANT,       _POSIX_SEM_NSEMS_MAX    },
 121   { "_POSIX_SEM_VALUE_MAX",             CONSTANT,       _POSIX_SEM_VALUE_MAX    },
 122   { "_POSIX_SIGQUEUE_MAX",              CONSTANT,       _POSIX_SIGQUEUE_MAX     },
 123   { "_POSIX_SSIZE_MAX",                 CONSTANT,       _POSIX_SSIZE_MAX        },
 124   { "_POSIX_SS_REPL_MAX",               CONSTANT,       _POSIX_SS_REPL_MAX      },
 125   { "_POSIX_STREAM_MAX",                CONSTANT,       _POSIX_STREAM_MAX       },
 126   { "_POSIX_SYMLINK_MAX",               CONSTANT,       _POSIX_SYMLINK_MAX      },
 127   { "_POSIX_SYMLOOP_MAX",               CONSTANT,       _POSIX_SYMLOOP_MAX      },
 128   { "_POSIX_THREAD_DESTRUCTOR_ITERATIONS", CONSTANT,    _POSIX_THREAD_DESTRUCTOR_ITERATIONS     },
 129   { "_POSIX_THREAD_KEYS_MAX",           CONSTANT,       _POSIX_THREAD_KEYS_MAX  },
 130   { "_POSIX_THREAD_THREADS_MAX",        CONSTANT,       _POSIX_THREAD_THREADS_MAX       },
 131   { "_POSIX_TIMER_MAX",                 CONSTANT,       _POSIX_TIMER_MAX        },
 132   { "_POSIX_TRACE_EVENT_NAME_MAX",      CONSTANT,       _POSIX_TRACE_EVENT_NAME_MAX     },
 133   { "_POSIX_TRACE_NAME_MAX",            CONSTANT,       _POSIX_TRACE_NAME_MAX   },
 134   { "_POSIX_TRACE_SYS_MAX",             CONSTANT,       _POSIX_TRACE_SYS_MAX    },
 135   { "_POSIX_TRACE_USER_EVENT_MAX",      CONSTANT,       _POSIX_TRACE_USER_EVENT_MAX     },
 136   { "_POSIX_TTY_NAME_MAX",              CONSTANT,       _POSIX_TTY_NAME_MAX     },
 137   { "_POSIX_TZNAME_MAX",                CONSTANT,       _POSIX_TZNAME_MAX       },
 138   { "_POSIX2_BC_BASE_MAX",              CONSTANT,       _POSIX2_BC_BASE_MAX     },
 139   { "_POSIX2_BC_DIM_MAX",               CONSTANT,       _POSIX2_BC_DIM_MAX      },
 140   { "_POSIX2_BC_SCALE_MAX",             CONSTANT,       _POSIX2_BC_SCALE_MAX    },
 141   { "_POSIX2_BC_STRING_MAX",            CONSTANT,       _POSIX2_BC_STRING_MAX   },
 142   { "_POSIX2_COLL_WEIGHTS_MAX",         CONSTANT,       _POSIX2_COLL_WEIGHTS_MAX        },
 143   { "_POSIX2_EXPR_NEXT_MAX",            CONSTANT,       _POSIX2_EXPR_NEST_MAX   },
 144   { "_POSIX2_LINE_MAX",                 CONSTANT,       _POSIX2_LINE_MAX        },
 145   { "_POSIX2_RE_DUP_MAX",               CONSTANT,       _POSIX2_RE_DUP_MAX      },
 146   { "_XOPEN_IOV_MAX",                   CONSTANT,       _XOPEN_IOV_MAX          },
 147   { "_XOPEN_NAME_MAX",                  CONSTANT,       _XOPEN_NAME_MAX         },
 148   { "_XOPEN_PATH_MAX",                  CONSTANT,       _XOPEN_PATH_MAX         },
 149   { "CHAR_BIT",                         CONSTANT,       CHAR_BIT        },
 150   { "CHAR_MAX",                         CONSTANT,       CHAR_MAX        },
 151   { "CHAR_MIN",                         CONSTANT,       CHAR_MIN        },
 152   { "INT_MAX",                          CONSTANT,       INT_MAX         },
 153   { "INT_MIN",                          CONSTANT,       INT_MIN         },
 154   { "LLONG_MIN",                        CONSTANT,       LLONG_MIN       },
 155   { "LLONG_MAX",                        CONSTANT,       LLONG_MAX       },
 156   { "LONG_BIT",                         CONSTANT,       LONG_BIT        },
 157   { "LONG_MAX",                         CONSTANT,       LONG_MAX        },
 158   { "LONG_MIN",                         CONSTANT,       LONG_MIN        },
 159   { "MB_LEN_MAX",                       CONSTANT,       MB_LEN_MAX      },
 160   { "SCHAR_MAX",                        CONSTANT,       SCHAR_MAX       },
 161   { "SCHAR_MIN",                        CONSTANT,       SCHAR_MIN       },
 162   { "SHRT_MAX",                         CONSTANT,       SHRT_MAX        },
 163   { "SHRT_MIN",                         CONSTANT,       SHRT_MIN        },
 164   { "SSIZE_MAX",                        CONSTANT,       SSIZE_MAX       },
 165   { "UCHAR_MAX",                        CONSTANT,       UCHAR_MAX       },
 166   { "UINT_MAX",                         CONSTANT,       UINT_MAX        },
 167   { "ULLONG_MAX",                       CONSTANT,       ULLONG_MAX      },
 168   { "ULONG_MAX",                        CONSTANT,       ULONG_MAX       },
 169   { "USHRT_MAX",                        CONSTANT,       USHRT_MAX       },
 170   { "WORD_BIT",                         CONSTANT,       WORD_BIT        },
 171   { "NL_ARGMAX",                        CONSTANT,       NL_ARGMAX       },
 172   { "ML_LANGMAX",                       CONSTANT,       NL_LANGMAX      },
 173   { "NL_MSGMAX",                        CONSTANT,       NL_MSGMAX       },
 174   { "NL_SETMAX",                        CONSTANT,       NL_SETMAX       },
 175   { "NL_TEXTMAX",                       CONSTANT,       NL_TEXTMAX      },
 176   { "NZERO",                            CONSTANT,       NZERO           },
 177   /* required by POSIX.1-2008 for compatibility with earlier versions */
 178   { "POSIX2_BC_BASE_MAX",               CONSTANT,       _POSIX2_BC_BASE_MAX     },
 179   { "POSIX2_BC_DIM_MAX",                CONSTANT,       _POSIX2_BC_DIM_MAX      },
 180   { "POSIX2_BC_SCALE_MAX",              CONSTANT,       _POSIX2_BC_SCALE_MAX    },
 181   { "POSIX2_BC_STRING_MAX",             CONSTANT,       _POSIX2_BC_STRING_MAX   },
 182   { "POSIX2_COLL_WEIGHTS_MAX",          CONSTANT,       _POSIX2_COLL_WEIGHTS_MAX        },
 183   { "POSIX2_EXPR_NEXT_MAX",             CONSTANT,       _POSIX2_EXPR_NEST_MAX   },
 184   { "POSIX2_LINE_MAX",                  CONSTANT,       _POSIX2_LINE_MAX        },
 185   { "POSIX2_RE_DUP_MAX",                CONSTANT,       _POSIX2_RE_DUP_MAX      },
 186
 187   /* Variables from fpathconf() */
 188   { "FILESIZEBITS",                     PATHCONF,       _PC_FILESIZEBITS        },
 189   { "LINK_MAX",                         PATHCONF,       _PC_LINK_MAX            },
 190   { "MAX_CANON",                        PATHCONF,       _PC_MAX_CANON           },
 191   { "MAX_INPUT",                        PATHCONF,       _PC_MAX_INPUT           },
 192   { "NAME_MAX",                         PATHCONF,       _PC_NAME_MAX            },
 193   { "PATH_MAX",                         PATHCONF,       _PC_PATH_MAX            },
 194   { "PIPE_BUF",                         PATHCONF,       _PC_PIPE_BUF            },
 195   { "POSIX2_SYMLINKS",                  PATHCONF,       _PC_2_SYMLINKS          },
 196   { "POSIX_ALLOC_SIZE_MIN",             PATHCONF,       _PC_ALLOC_SIZE_MIN      },
 197   { "POSIX_REC_INCR_XFER_SIZE",         PATHCONF,       _PC_REC_INCR_XFER_SIZE  },
 198   { "POSIX_REC_MAX_XFER_SIZE",          PATHCONF,       _PC_REC_MAX_XFER_SIZE   },
 199   { "POSIX_REC_MIN_XFER_SIZE",          PATHCONF,       _PC_REC_MIN_XFER_SIZE   },
 200   { "POSIX_REC_XFER_ALIGN",             PATHCONF,       _PC_REC_XFER_ALIGN      },
 201   { "SYMLINK_MAX",                      PATHCONF,       _PC_SYMLINK_MAX         },
 202   { "_POSIX_CHOWN_RESTRICTED",          PATHCONF,       _PC_CHOWN_RESTRICTED    },
 203   { "_POSIX_NO_TRUNC",                  PATHCONF,       _PC_NO_TRUNC            },
 204   { "_POSIX_VDISABLE",                  PATHCONF,       _PC_VDISABLE            },
 205   { "_POSIX_ASYNC_IO",                  PATHCONF,       _PC_ASYNC_IO            },
 206   { "_POSIX_PRIO_IO",                   PATHCONF,       _PC_PRIO_IO             },
 207   { "_POSIX_SYNC_IO",                   PATHCONF,       _PC_SYNC_IO             },
 208   { "_POSIX_TIMESTAMP_RESOLUTION",      PATHCONF,       _PC_TIMESTAMP_RESOLUTION        },
 209
 210   /* Variables from sysconf() */
 211   { "AIO_LISTIO_MAX",                   SYSCONF,        _SC_AIO_LISTIO_MAX      },
 212   { "AIO_MAX",                          SYSCONF,        _SC_AIO_MAX             },
 213   { "AIO_PRIO_DELTA_MAX",               SYSCONF,        _SC_AIO_PRIO_DELTA_MAX  },
 214   { "ARG_MAX",                          SYSCONF,        _SC_ARG_MAX             },
 215   { "ATEXIT_MAX",                       SYSCONF,        _SC_ATEXIT_MAX          },
 216   { "BC_BASE_MAX",                      SYSCONF,        _SC_BC_BASE_MAX         },
 217   { "BC_DIM_MAX",                       SYSCONF,        _SC_BC_DIM_MAX          },
 218   { "BC_SCALE_MAX",                     SYSCONF,        _SC_BC_SCALE_MAX        },
 219   { "BC_STRING_MAX",                    SYSCONF,        _SC_BC_STRING_MAX       },
 220   { "CHILD_MAX",                        SYSCONF,        _SC_CHILD_MAX           },
 221   { "CLK_TCK",                          SYSCONF,        _SC_CLK_TCK             },
 222   { "COLL_WEIGHTS_MAX",                 SYSCONF,        _SC_COLL_WEIGHTS_MAX    },
 223   { "DELAYTIMER_MAX",                   SYSCONF,        _SC_DELAYTIMER_MAX      },
 224   { "EXPR_NEST_MAX",                    SYSCONF,        _SC_EXPR_NEST_MAX       },
 225   { "GETGR_R_SIZE_MAX",                 SYSCONF,        _SC_GETGR_R_SIZE_MAX    },
 226   { "GETPW_R_SIZE_MAX",                 SYSCONF,        _SC_GETPW_R_SIZE_MAX    },
 227   { "HOST_NAME_MAX",                    SYSCONF,        _SC_HOST_NAME_MAX       },
 228   { "IOV_MAX",                          SYSCONF,        _SC_IOV_MAX             },
 229   { "LINE_MAX",                         SYSCONF,        _SC_LINE_MAX            },
 230   { "LOGIN_NAME_MAX",                   SYSCONF,        _SC_LOGIN_NAME_MAX      },
 231   { "MQ_OPEN_MAX",                      SYSCONF,        _SC_MQ_OPEN_MAX         },
 232   { "MQ_PRIO_MAX",                      SYSCONF,        _SC_MQ_PRIO_MAX         },
 233   { "NGROUPS_MAX",                      SYSCONF,        _SC_NGROUPS_MAX         },
 234   { "OPEN_MAX",                         SYSCONF,        _SC_OPEN_MAX            },
 235   { "PAGE_SIZE",                        SYSCONF,        _SC_PAGESIZE            },
 236   { "PAGESIZE",                         SYSCONF,        _SC_PAGESIZE            },
 237   { "PTHREAD_DESTRUCTOR_ITERATIONS",    SYSCONF,        _SC_THREAD_DESTRUCTOR_ITERATIONS        },
 238   { "PTHREAD_KEYS_MAX",                 SYSCONF,        _SC_THREAD_KEYS_MAX     },
 239   { "PTHREAD_STACK_MIN",                SYSCONF,        _SC_THREAD_STACK_MIN    },
 240   { "PTHREAD_THREADS_MAX",              SYSCONF,        _SC_THREAD_THREADS_MAX  },
 241   { "RE_DUP_MAX",                       SYSCONF,        _SC_RE_DUP_MAX          },
 242   { "RTSIG_MAX",                        SYSCONF,        _SC_RTSIG_MAX           },
 243   { "SEM_NSEMS_MAX",                    SYSCONF,        _SC_SEM_NSEMS_MAX       },
 244   { "SEM_VALUE_MAX",                    SYSCONF,        _SC_SEM_VALUE_MAX       },
 245   { "SIGQUEUE_MAX",                     SYSCONF,        _SC_SIGQUEUE_MAX        },
 246   { "STREAM_MAX",                       SYSCONF,        _SC_STREAM_MAX          },
 247   { "SYMLOOP_MAX",                      SYSCONF,        _SC_SYMLOOP_MAX         },
 248   { "TIMER_MAX",                        SYSCONF,        _SC_TIMER_MAX           },
 249   { "TTY_NAME_MAX",                     SYSCONF,        _SC_TTY_NAME_MAX        },
 250   { "TZNAME_MAX",                       SYSCONF,        _SC_TZNAME_MAX          },
 251   { "_POSIX_ADVISORY_INFO",             SYSCONF,        _SC_ADVISORY_INFO       },
 252   { "_POSIX_ASYNCHRONOUS_IO",           SYSCONF,        _SC_ASYNCHRONOUS_IO     },
 253   { "_POSIX_BARRIERS",                  SYSCONF,        _SC_BARRIERS            },
 254   { "_POSIX_CLOCK_SELECTION",           SYSCONF,        _SC_CLOCK_SELECTION     },
 255   { "_POSIX_CPUTIME",                   SYSCONF,        _SC_CPUTIME             },
 256   { "_POSIX_FSYNC",                     SYSCONF,        _SC_FSYNC               },
 257   { "_POSIX_IPV6",                      SYSCONF,        _SC_IPV6                },
 258   { "_POSIX_JOB_CONTROL",               SYSCONF,        _SC_JOB_CONTROL         },
 259   { "_POSIX_MAPPED_FILES",              SYSCONF,        _SC_MAPPED_FILES        },
 260   { "_POSIX_MEMLOCK",                   SYSCONF,        _SC_MEMLOCK             },
 261   { "_POSIX_MEMLOCK_RANGE",             SYSCONF,        _SC_MEMLOCK_RANGE       },
 262   { "_POSIX_MEMORY_PROTECTION",         SYSCONF,        _SC_MEMORY_PROTECTION   },
 263   { "_POSIX_MESSAGE_PASSING",           SYSCONF,        _SC_MESSAGE_PASSING     },
 264   { "_POSIX_MONOTONIC_CLOCK",           SYSCONF,        _SC_MONOTONIC_CLOCK     },
 265   { "_POSIX_PRIORITIZED_IO",            SYSCONF,        _SC_PRIORITIZED_IO      },
 266   { "_POSIX_PRIORITY_SCHEDULING",       SYSCONF,        _SC_PRIORITY_SCHEDULING         },
 267   { "_POSIX_RAW_SOCKETS",               SYSCONF,        _SC_RAW_SOCKETS         },
 268   { "_POSIX_READER_WRITER_LOCKS",       SYSCONF,        _SC_READER_WRITER_LOCKS },
 269   { "_POSIX_REALTIME_SIGNALS",          SYSCONF,        _SC_REALTIME_SIGNALS    },
 270   { "_POSIX_REGEXP",                    SYSCONF,        _SC_REGEXP              },
 271   { "_POSIX_SAVED_IDS",                 SYSCONF,        _SC_SAVED_IDS           },
 272   { "_POSIX_SEMAPHORES",                SYSCONF,        _SC_SEMAPHORES          },
 273   { "_POSIX_SHARED_MEMORY_OBJECTS",     SYSCONF,        _SC_SHARED_MEMORY_OBJECTS       },
 274   { "_POSIX_SHELL",                     SYSCONF,        _SC_SHELL               },
 275   { "_POSIX_SPAWN",                     SYSCONF,        _SC_SPAWN               },
 276   { "_POSIX_SPIN_LOCKS",                SYSCONF,        _SC_SPIN_LOCKS          },
 277   { "_POSIX_SPORADIC_SERVER",           SYSCONF,        _SC_SPORADIC_SERVER     },
 278   { "_POSIX_SS_REPL_MAX",               SYSCONF,        _SC_SS_REPL_MAX         },
 279   { "_POSIX_SYNCHRONIZED_IO",           SYSCONF,        _SC_SYNCHRONIZED_IO     },
 280   { "_POSIX_THREAD_ATTR_STACKADDR",     SYSCONF,        _SC_THREAD_ATTR_STACKADDR       },
 281   { "_POSIX_THREAD_ATTR_STACKSIZE",     SYSCONF,        _SC_THREAD_ATTR_STACKSIZE       },
 282   { "_POSIX_THREAD_CPUTIME",            SYSCONF,        _SC_THREAD_CPUTIME      },
 283   { "_POSIX_THREAD_PRIO_INHERIT",       SYSCONF,        _SC_THREAD_PRIO_INHERIT         },
 284   { "_POSIX_THREAD_PRIO_PROTECT",       SYSCONF,        _SC_THREAD_PRIO_PROTECT         },
 285   { "_POSIX_THREAD_PRIORITY_SCHEDULING",SYSCONF,        _SC_THREAD_PRIORITY_SCHEDULING  },
 286   { "_POSIX_THREAD_PROCESS_SHARED",     SYSCONF,        _SC_THREAD_PROCESS_SHARED       },
 287   { "_POSIX_THREAD_ROBUST_PRIO_INHERIT",SYSCONF,        _SC_THREAD_ROBUST_PRIO_INHERIT  },
 288   { "_POSIX_THREAD_ROBUST_PRIO_PROTECT",SYSCONF,        _SC_THREAD_ROBUST_PRIO_PROTECT  },
 289   { "_POSIX_THREAD_SAFE_FUNCTIONS",     SYSCONF,        _SC_THREAD_SAFE_FUNCTIONS       },
 290   { "_POSIX_THREAD_SPORADIC_SERVER",    SYSCONF,        _SC_THREAD_SPORADIC_SERVER      },
 291   { "_POSIX_THREADS",                   SYSCONF,        _SC_THREADS             },
 292   { "_POSIX_TIMEOUTS",                  SYSCONF,        _SC_TIMEOUTS            },
 293   { "_POSIX_TIMERS",                    SYSCONF,        _SC_TIMERS              },
 294   { "_POSIX_TRACE",                     SYSCONF,        _SC_TRACE               },
 295   { "_POSIX_TRACE_EVENT_FILTER",        SYSCONF,        _SC_TRACE_EVENT_FILTER  },
 296   { "_POSIX_TRACE_EVENT_NAME_MAX",      SYSCONF,        _SC_TRACE_EVENT_NAME_MAX        },
 297   { "_POSIX_TRACE_INHERIT",             SYSCONF,        _SC_TRACE_INHERIT       },
 298   { "_POSIX_TRACE_LOG",                 SYSCONF,        _SC_TRACE_LOG           },
 299   { "_POSIX_TRACE_NAME_MAX",            SYSCONF,        _SC_TRACE_NAME_MAX              },
 300   { "_POSIX_TRACE_SYS_MAX",             SYSCONF,        _SC_TRACE_SYS_MAX               },
 301   { "_POSIX_TRACE_USER_EVENT_MAX",      SYSCONF,        _SC_TRACE_USER_EVENT_MAX                },
 302   { "_POSIX_TYPED_MEMORY_OBJECTS",      SYSCONF,        _SC_TYPED_MEMORY_OBJECTS        },
 303   { "_POSIX_VERSION",                   SYSCONF,        _SC_VERSION             },
 304   { "_POSIX_V7_ILP32_OFF32",            SYSCONF,        _SC_V7_ILP32_OFF32      },
 305   { "_POSIX_V7_ILP32_OFFBIG",           SYSCONF,        _SC_V7_ILP32_OFFBIG     },
 306   { "_POSIX_V7_LP64_OFF64",             SYSCONF,        _SC_V7_LP64_OFF64       },
 307   { "_POSIX_V7_LPBIG_OFFBIG",           SYSCONF,        _SC_V7_LPBIG_OFFBIG     },
 308   { "_POSIX_V6_ILP32_OFF32",            SYSCONF,        _SC_V6_ILP32_OFF32      },
 309   { "_POSIX_V6_ILP32_OFFBIG",           SYSCONF,        _SC_V6_ILP32_OFFBIG     },
 310   { "_POSIX_V6_LP64_OFF64",             SYSCONF,        _SC_V6_LP64_OFF64       },
 311   { "_POSIX_V6_LPBIG_OFFBIG",           SYSCONF,        _SC_V6_LPBIG_OFFBIG     },
 312   { "_POSIX2_C_BIND",                   SYSCONF,        _SC_2_C_BIND            },
 313   { "_POSIX2_C_DEV",                    SYSCONF,        _SC_2_C_DEV             },
 314   { "_POSIX2_CHAR_TERM",                SYSCONF,        _SC_2_CHAR_TERM         },
 315   { "_POSIX2_FORT_DEV",                 SYSCONF,        _SC_2_FORT_DEV          },
 316   { "_POSIX2_FORT_RUN",                 SYSCONF,        _SC_2_FORT_RUN          },
 317   { "_POSIX2_LOCALEDEF",                SYSCONF,        _SC_2_LOCALEDEF         },
 318   { "_POSIX2_PBS",                      SYSCONF,        _SC_2_PBS               },
 319   { "_POSIX2_PBS_ACCOUNTING",           SYSCONF,        _SC_2_PBS_ACCOUNTING    },
 320   { "_POSIX2_PBS_CHECKPOINT",           SYSCONF,        _SC_2_PBS_CHECKPOINT    },
 321   { "_POSIX2_PBS_LOCATE",               SYSCONF,        _SC_2_PBS_LOCATE        },
 322   { "_POSIX2_PBS_MESSAGE",              SYSCONF,        _SC_2_PBS_MESSAGE       },
 323   { "_POSIX2_PBS_TRACK",                SYSCONF,        _SC_2_PBS_TRACK         },
 324   { "_POSIX2_SW_DEV",                   SYSCONF,        _SC_2_SW_DEV            },
 325   { "_POSIX2_UPE",                      SYSCONF,        _SC_2_UPE               },
 326   { "_POSIX2_VERSION",                  SYSCONF,        _SC_2_VERSION           },
 327   { "_XBS5_ILP32_OFF32",                SYSCONF,        _SC_XBS5_ILP32_OFF32    },
 328   { "_XBS5_ILP32_OFFBIG",               SYSCONF,        _SC_XBS5_ILP32_OFFBIG   },
 329   { "_XBS5_LP64_OFF64",                 SYSCONF,        _SC_XBS5_LP64_OFF64     },
 330   { "_XBS5_LPBIG_OFFBIG",               SYSCONF,        _SC_XBS5_LPBIG_OFFBIG   },
 331   { "_XOPEN_CRYPT",                     SYSCONF,        _SC_XOPEN_CRYPT         },
 332   { "_XOPEN_ENH_I18N",                  SYSCONF,        _SC_XOPEN_ENH_I18N      },
 333   { "_XOPEN_LEGACY",                    SYSCONF,        _SC_XOPEN_LEGACY        },
 334   { "_XOPEN_REALTIME",                  SYSCONF,        _SC_XOPEN_REALTIME      },
 335   { "_XOPEN_REALTIME_THREADS",          SYSCONF,        _SC_XOPEN_REALTIME_THREADS      },
 336   { "_XOPEN_SHM",                       SYSCONF,        _SC_XOPEN_SHM           },
 337   { "_XOPEN_STREAMS",                   SYSCONF,        _SC_XOPEN_STREAMS       },
 338   { "_XOPEN_UNIX",                      SYSCONF,        _SC_XOPEN_UNIX          },
 339   { "_XOPEN_UUCP",                      SYSCONF,        _SC_XOPEN_UUCP          },
 340   { "_XOPEN_VERSION",                   SYSCONF,        _SC_XOPEN_VERSION       },
 341   /* for compatibility with earlier versions */
 342   { "POSIX2_C_BIND",                    SYSCONF,        _SC_2_C_BIND            },
 343   { "POSIX2_C_DEV",                     SYSCONF,        _SC_2_C_DEV             },
 344   { "POSIX2_CHAR_TERM",                 SYSCONF,        _SC_2_CHAR_TERM         },
 345   { "POSIX2_FORT_DEV",                  SYSCONF,        _SC_2_FORT_DEV          },
 346   { "POSIX2_FORT_RUN",                  SYSCONF,        _SC_2_FORT_RUN          },
 347   { "POSIX2_LOCALEDEF",                 SYSCONF,        _SC_2_LOCALEDEF         },
 348   { "POSIX2_PBS",                       SYSCONF,        _SC_2_PBS               },
 349   { "POSIX2_PBS_ACCOUNTING",            SYSCONF,        _SC_2_PBS_ACCOUNTING    },
 350   { "POSIX2_PBS_CHECKPOINT",            SYSCONF,        _SC_2_PBS_CHECKPOINT    },
 351   { "POSIX2_PBS_LOCATE",                SYSCONF,        _SC_2_PBS_LOCATE        },
 352   { "POSIX2_PBS_MESSAGE",               SYSCONF,        _SC_2_PBS_MESSAGE       },
 353   { "POSIX2_PBS_TRACK",                 SYSCONF,        _SC_2_PBS_TRACK         },
 354   { "POSIX2_SW_DEV",                    SYSCONF,        _SC_2_SW_DEV            },
 355   { "POSIX2_UPE",                       SYSCONF,        _SC_2_UPE               },
 356   { "POSIX2_VERSION",                   SYSCONF,        _SC_2_VERSION           },
 357   /* implementation-specific values */
 358   { "_NPROCESSORS_CONF",                SYSCONF,        _SC_NPROCESSORS_CONF    },
 359   { "_NPROCESSORS_ONLN",                SYSCONF,        _SC_NPROCESSORS_ONLN    },
 360   { "_AVPHYS_PAGES",                    SYSCONF,        _SC_AVPHYS_PAGES        },
 361   { "_PHYS_PAGES",                      SYSCONF,        _SC_PHYS_PAGES          },
 362
 363   { NULL,                               CONSTANT,        0L }
 364 };
 365
 366 struct spec_variable {
 367   const char *name;
 368   int valid;
 369 };
 370
 371 static const struct spec_variable spec_table[] = {
 372   { "POSIX_V7_ILP32_OFF32",     0 },
 373   { "POSIX_V7_ILP32_OFFBIG",    1 },
 374   { "POSIX_V7_LP64_OFF64",      0 },
 375   { "POSIX_V7_LPBIG_OFFBIG",    0 },
 376   { "POSIX_V6_ILP32_OFF32",     0 },
 377   { "POSIX_V6_ILP32_OFFBIG",    1 },
 378   { "POSIX_V6_LP64_OFF64",      0 },
 379   { "POSIX_V6_LPBIG_OFFBIG",    0 },
 380   { "XBS5_ILP32_OFF32",         0 },
 381   { "XBS5_ILP32_OFFBIG",        1 },
 382   { "XBS5_LP64_OFF64",          0 },
 383   { "XBS5_LPBIG_OFFBIG",        0 },
 384   { NULL, 0 },
 385 };
 386
 387 static int a_flag = 0;          /* list all variables */
 388 static int v_flag = 0;          /* follow given specification */
 389
 390 static void
 391 print_longvar (const char *name, long long value)
 392 {
 393   if (a_flag)
 394     printf ("%-35s %lld\n", name, value);
 395   else
 396     printf ("%lld\n", value);
 397 }
 398
 399 static void
 400 print_strvar (const char *name, const char *sval)
 401 {
 402   if (a_flag)
 403     printf ("%-35s %s\n", name, sval);
 404   else
 405     printf ("%s\n", sval);
 406 }
 407
 408 static void
 409 printvar (const struct conf_variable *cp, const char *pathname)
 410 {
 411   size_t slen;
 412   char *sval;
 413   long val;
 414
 415   switch (cp->type)
 416     {
 417     case CONSTANT:
 418       print_longvar (cp->name, cp->value);
 419       break;
 420
 421     case CONFSTR:
 422       errno = 0;
 423       slen = confstr ((int) cp->value, NULL, 0);
 424       if (slen == 0)
 425         {
 426           if (errno == 0)
 427             print_strvar (cp->name, "undefined");
 428           return;
 429         }
 430
 431       if ((sval = malloc (slen)) == NULL)
 432         error (EXIT_FAILURE, 0, "Can't allocate %zu bytes", slen);
 433
 434       errno = 0;
 435       if (confstr ((int) cp->value, sval, slen) == 0)
 436         print_strvar (cp->name, "undefined");
 437       else
 438         print_strvar (cp->name, sval);
 439
 440       free (sval);
 441       break;
 442
 443     case SYSCONF:
 444       errno = 0;
 445       if ((val = sysconf ((int) cp->value)) == -1)
 446         {
 447           if (a_flag && errno != 0)
 448             return; /* Just skip invalid variables */
 449           print_strvar (cp->name, "undefined");
 450         }
 451       else
 452         print_longvar (cp->name, val);
 453       break;
 454
 455     case PATHCONF:
 456       errno = 0;
 457       if ((val = pathconf (pathname, (int) cp->value)) == -1)
 458         {
 459           if (a_flag && errno != 0)
 460             return; /* Just skip invalid variables */
 461           print_strvar (cp->name, "undefined");
 462         }
 463       else
 464         print_longvar (cp->name, val);
 465       break;
 466     }
 467 }
 468
 469 static void
 470 usage (void)
 471 {
 472   fprintf (stderr,
 473            "Usage: %s [-v specification] variable_name [pathname]\n"
 474            "       %s -a [pathname]\n",
 475            program_invocation_short_name, program_invocation_short_name);
 476   exit (EXIT_FAILURE);
 477 }
 478
 479 int
 480 main (int argc, char **argv)
 481 {
 482   int ch;
 483   const struct conf_variable *cp;
 484   const struct spec_variable *sp;
 485   const char *varname, *pathname;
 486   int found;
 487
 488   setlocale (LC_ALL, "");
 489
 490   while ((ch = getopt (argc, argv, "av")) != -1)
 491     {
 492       switch (ch)
 493         {
 494         case 'a':
 495           a_flag = 1;
 496           break;
 497         case 'v':
 498           v_flag = 1;
 499           break;
 500         case '?':
 501         default:
 502           usage ();
 503         }
 504     }
 505   argc -= optind;
 506   argv += optind;
 507
 508   if (v_flag)
 509     {
 510       if (a_flag || argc < 2)
 511         usage ();
 512       for (sp = spec_table; sp->name != NULL; sp++)
 513         {
 514           if (strcmp (argv[0], sp->name) == 0)
 515             {
 516               if (sp->valid != 1)
 517                 error (EXIT_FAILURE, 0, "unsupported specification \"%s\"", argv[0]);
 518               break;
 519             }
 520         }
 521       if (sp->name == NULL)
 522         error (EXIT_FAILURE, 0, "unknown specification \"%s\"", argv[0]);
 523       argc--;
 524       argv++;
 525     }
 526
 527   if (!a_flag)
 528     {
 529       if (argc == 0)
 530         usage ();
 531       varname = argv[0];
 532       argc--;
 533       argv++;
 534     }
 535   else
 536     varname = NULL;
 537
 538   if (argc > 1)
 539     usage ();
 540   pathname = argv[0];  /* may be NULL */
 541
 542   found = 0;
 543   for (cp = conf_table; cp->name != NULL; cp++)
 544     {
 545       if (a_flag || strcmp (varname, cp->name) == 0)
 546         {
 547           /* LINTED weird expression */
 548           if ((cp->type == PATHCONF) == (pathname != NULL))
 549             {
 550               printvar (cp, pathname);
 551               found = 1;
 552             }
 553           else if (!a_flag)
 554             usage ();
 555         }
 556     }
 557
 558   if (!a_flag && !found)
 559     error (EXIT_FAILURE, 0, "Unrecognized variable `%s'", varname);
 560
 561   fflush (stdout);
 562   return ferror (stdout) ? EXIT_FAILURE : EXIT_SUCCESS;
 563 }
 564