getconf.c (11614B)
1 /*- 2 * Copyright (c) 1996, 1998 The NetBSD Foundation, Inc. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to The NetBSD Foundation 6 * by J.T. Conklin. 7 * 8 * Mostly rewritten to be used in Alpine Linux (with musl c-library) 9 * by Timo Teräs. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <err.h> 34 #include <errno.h> 35 #include <values.h> 36 #include <limits.h> 37 #include <locale.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <unistd.h> 41 #include <string.h> 42 43 struct conf_variable { 44 const char *name; 45 enum { SYSCONF, CONFSTR, PATHCONF, CONSTANT, UCONSTANT, NUM_TYPES } type; 46 long value; 47 }; 48 49 static const struct conf_variable conf_table[] = { 50 { "PATH", CONFSTR, _CS_PATH }, 51 52 /* Utility Limit Minimum Values */ 53 { "POSIX2_BC_BASE_MAX", CONSTANT, _POSIX2_BC_BASE_MAX }, 54 { "POSIX2_BC_DIM_MAX", CONSTANT, _POSIX2_BC_DIM_MAX }, 55 { "POSIX2_BC_SCALE_MAX", CONSTANT, _POSIX2_BC_SCALE_MAX }, 56 { "POSIX2_BC_STRING_MAX", CONSTANT, _POSIX2_BC_STRING_MAX }, 57 { "POSIX2_COLL_WEIGHTS_MAX", CONSTANT, _POSIX2_COLL_WEIGHTS_MAX }, 58 { "POSIX2_EXPR_NEST_MAX", CONSTANT, _POSIX2_EXPR_NEST_MAX }, 59 { "POSIX2_LINE_MAX", CONSTANT, _POSIX2_LINE_MAX }, 60 { "POSIX2_RE_DUP_MAX", CONSTANT, _POSIX2_RE_DUP_MAX }, 61 { "POSIX2_VERSION", CONSTANT, _POSIX2_VERSION }, 62 63 /* POSIX.1 Minimum Values */ 64 { "_POSIX_AIO_LISTIO_MAX", CONSTANT, _POSIX_AIO_LISTIO_MAX }, 65 { "_POSIX_AIO_MAX", CONSTANT, _POSIX_AIO_MAX }, 66 { "_POSIX_ARG_MAX", CONSTANT, _POSIX_ARG_MAX }, 67 { "_POSIX_CHILD_MAX", CONSTANT, _POSIX_CHILD_MAX }, 68 { "_POSIX_LINK_MAX", CONSTANT, _POSIX_LINK_MAX }, 69 { "_POSIX_MAX_CANON", CONSTANT, _POSIX_MAX_CANON }, 70 { "_POSIX_MAX_INPUT", CONSTANT, _POSIX_MAX_INPUT }, 71 { "_POSIX_MQ_OPEN_MAX", CONSTANT, _POSIX_MQ_OPEN_MAX }, 72 { "_POSIX_MQ_PRIO_MAX", CONSTANT, _POSIX_MQ_PRIO_MAX }, 73 { "_POSIX_NAME_MAX", CONSTANT, _POSIX_NAME_MAX }, 74 { "_POSIX_NGROUPS_MAX", CONSTANT, _POSIX_NGROUPS_MAX }, 75 { "_POSIX_OPEN_MAX", CONSTANT, _POSIX_OPEN_MAX }, 76 { "_POSIX_PATH_MAX", CONSTANT, _POSIX_PATH_MAX }, 77 { "_POSIX_PIPE_BUF", CONSTANT, _POSIX_PIPE_BUF }, 78 { "_POSIX_SSIZE_MAX", CONSTANT, _POSIX_SSIZE_MAX }, 79 { "_POSIX_STREAM_MAX", CONSTANT, _POSIX_STREAM_MAX }, 80 { "_POSIX_TZNAME_MAX", CONSTANT, _POSIX_TZNAME_MAX }, 81 82 /* Symbolic Utility Limits */ 83 { "BC_BASE_MAX", SYSCONF, _SC_BC_BASE_MAX }, 84 { "BC_DIM_MAX", SYSCONF, _SC_BC_DIM_MAX }, 85 { "BC_SCALE_MAX", SYSCONF, _SC_BC_SCALE_MAX }, 86 { "BC_STRING_MAX", SYSCONF, _SC_BC_STRING_MAX }, 87 { "COLL_WEIGHTS_MAX", SYSCONF, _SC_COLL_WEIGHTS_MAX }, 88 { "EXPR_NEST_MAX", SYSCONF, _SC_EXPR_NEST_MAX }, 89 { "LINE_MAX", SYSCONF, _SC_LINE_MAX }, 90 { "RE_DUP_MAX", SYSCONF, _SC_RE_DUP_MAX }, 91 92 /* Optional Facility Configuration Values */ 93 { "_POSIX2_C_BIND", SYSCONF, _SC_2_C_BIND }, 94 { "POSIX2_C_DEV", SYSCONF, _SC_2_C_DEV }, 95 { "POSIX2_CHAR_TERM", SYSCONF, _SC_2_CHAR_TERM }, 96 { "POSIX2_FORT_DEV", SYSCONF, _SC_2_FORT_DEV }, 97 { "POSIX2_FORT_RUN", SYSCONF, _SC_2_FORT_RUN }, 98 { "POSIX2_LOCALEDEF", SYSCONF, _SC_2_LOCALEDEF }, 99 { "POSIX2_SW_DEV", SYSCONF, _SC_2_SW_DEV }, 100 { "POSIX2_UPE", SYSCONF, _SC_2_UPE }, 101 102 /* POSIX.1 Configurable System Variables */ 103 { "AIO_LISTIO_MAX", SYSCONF, _SC_AIO_LISTIO_MAX }, 104 { "AIO_MAX", SYSCONF, _SC_AIO_MAX }, 105 { "ARG_MAX", SYSCONF, _SC_ARG_MAX }, 106 { "CHILD_MAX", SYSCONF, _SC_CHILD_MAX }, 107 { "CLK_TCK", SYSCONF, _SC_CLK_TCK }, 108 { "MQ_OPEN_MAX", SYSCONF, _SC_MQ_OPEN_MAX }, 109 { "MQ_PRIO_MAX", SYSCONF, _SC_MQ_PRIO_MAX }, 110 { "NGROUPS_MAX", SYSCONF, _SC_NGROUPS_MAX }, 111 { "OPEN_MAX", SYSCONF, _SC_OPEN_MAX }, 112 { "STREAM_MAX", SYSCONF, _SC_STREAM_MAX }, 113 { "TZNAME_MAX", SYSCONF, _SC_TZNAME_MAX }, 114 { "_POSIX_JOB_CONTROL", SYSCONF, _SC_JOB_CONTROL }, 115 { "_POSIX_SAVED_IDS", SYSCONF, _SC_SAVED_IDS }, 116 { "_POSIX_VERSION", SYSCONF, _SC_VERSION }, 117 118 { "LINK_MAX", PATHCONF, _PC_LINK_MAX }, 119 { "MAX_CANON", PATHCONF, _PC_MAX_CANON }, 120 { "MAX_INPUT", PATHCONF, _PC_MAX_INPUT }, 121 { "NAME_MAX", PATHCONF, _PC_NAME_MAX }, 122 { "PATH_MAX", PATHCONF, _PC_PATH_MAX }, 123 { "PIPE_BUF", PATHCONF, _PC_PIPE_BUF }, 124 { "_POSIX_CHOWN_RESTRICTED", PATHCONF, _PC_CHOWN_RESTRICTED }, 125 { "_POSIX_NO_TRUNC", PATHCONF, _PC_NO_TRUNC }, 126 { "_POSIX_VDISABLE", PATHCONF, _PC_VDISABLE }, 127 128 /* POSIX.1b Configurable System Variables */ 129 { "PAGESIZE", SYSCONF, _SC_PAGESIZE }, 130 { "_POSIX_ASYNCHRONOUS_IO", SYSCONF, _SC_ASYNCHRONOUS_IO }, 131 { "_POSIX_FSYNC", SYSCONF, _SC_FSYNC }, 132 { "_POSIX_MAPPED_FILES", SYSCONF, _SC_MAPPED_FILES }, 133 { "_POSIX_MEMLOCK", SYSCONF, _SC_MEMLOCK }, 134 { "_POSIX_MEMLOCK_RANGE", SYSCONF, _SC_MEMLOCK_RANGE }, 135 { "_POSIX_MEMORY_PROTECTION", SYSCONF, _SC_MEMORY_PROTECTION }, 136 { "_POSIX_MESSAGE_PASSING", SYSCONF, _SC_MESSAGE_PASSING }, 137 { "_POSIX_MONOTONIC_CLOCK", SYSCONF, _SC_MONOTONIC_CLOCK }, 138 { "_POSIX_PRIORITY_SCHEDULING", SYSCONF, _SC_PRIORITY_SCHEDULING }, 139 { "_POSIX_SEMAPHORES", SYSCONF, _SC_SEMAPHORES }, 140 { "_POSIX_SHARED_MEMORY_OBJECTS", SYSCONF, _SC_SHARED_MEMORY_OBJECTS }, 141 { "_POSIX_SYNCHRONIZED_IO", SYSCONF, _SC_SYNCHRONIZED_IO }, 142 { "_POSIX_TIMERS", SYSCONF, _SC_TIMERS }, 143 144 { "_POSIX_SYNC_IO", PATHCONF, _PC_SYNC_IO }, 145 146 /* POSIX.1c Configurable System Variables */ 147 { "LOGIN_NAME_MAX", SYSCONF, _SC_LOGIN_NAME_MAX }, 148 { "_POSIX_THREADS", SYSCONF, _SC_THREADS }, 149 150 /* POSIX.1j Configurable System Variables */ 151 { "_POSIX_BARRIERS", SYSCONF, _SC_BARRIERS }, 152 { "_POSIX_READER_WRITER_LOCKS", SYSCONF, _SC_READER_WRITER_LOCKS }, 153 { "_POSIX_SPIN_LOCKS", SYSCONF, _SC_SPIN_LOCKS }, 154 155 /* XPG4.2 Configurable System Variables */ 156 { "IOV_MAX", SYSCONF, _SC_IOV_MAX }, 157 { "PAGE_SIZE", SYSCONF, _SC_PAGE_SIZE }, 158 { "_XOPEN_SHM", SYSCONF, _SC_XOPEN_SHM }, 159 160 /* X/Open CAE Spec. Issue 5 Version 2 Configurable System Variables */ 161 { "FILESIZEBITS", PATHCONF, _PC_FILESIZEBITS }, 162 163 /* POSIX.1-2001 XSI Option Group Configurable System Variables */ 164 { "ATEXIT_MAX", SYSCONF, _SC_ATEXIT_MAX }, 165 166 /* POSIX.1-2001 TSF Configurable System Variables */ 167 { "GETGR_R_SIZE_MAX", SYSCONF, _SC_GETGR_R_SIZE_MAX }, 168 { "GETPW_R_SIZE_MAX", SYSCONF, _SC_GETPW_R_SIZE_MAX }, 169 170 /* Commonly provided extensions */ 171 { "_PHYS_PAGES", SYSCONF, _SC_PHYS_PAGES }, 172 { "_AVPHYS_PAGES", SYSCONF, _SC_AVPHYS_PAGES }, 173 { "_NPROCESSORS_CONF", SYSCONF, _SC_NPROCESSORS_CONF }, 174 { "_NPROCESSORS_ONLN", SYSCONF, _SC_NPROCESSORS_ONLN }, 175 176 /* Data type related extensions */ 177 { "CHAR_BIT", CONSTANT, CHAR_BIT }, 178 { "CHAR_MAX", CONSTANT, CHAR_MAX }, 179 { "CHAR_MIN", CONSTANT, CHAR_MIN }, 180 { "INT_MAX", CONSTANT, INT_MAX }, 181 { "INT_MIN", CONSTANT, INT_MIN }, 182 { "LONG_BIT", CONSTANT, LONG_BIT }, 183 { "LONG_MAX", CONSTANT, LONG_MAX }, 184 { "LONG_MIN", CONSTANT, LONG_MIN }, 185 { "SCHAR_MAX", CONSTANT, SCHAR_MAX }, 186 { "SCHAR_MIN", CONSTANT, SCHAR_MIN }, 187 { "SHRT_MAX", CONSTANT, SHRT_MAX }, 188 { "SHRT_MIN", CONSTANT, SHRT_MIN }, 189 { "SSIZE_MAX", CONSTANT, SSIZE_MAX }, 190 { "UCHAR_MAX", UCONSTANT, (long) UCHAR_MAX }, 191 { "UINT_MAX", UCONSTANT, (long) UINT_MAX }, 192 { "ULONG_MAX", UCONSTANT, (long) ULONG_MAX }, 193 { "USHRT_MAX", UCONSTANT, (long) USHRT_MAX }, 194 { "WORD_BIT", CONSTANT, WORD_BIT }, 195 196 { NULL, CONSTANT, 0L } 197 }; 198 199 static int all = 0; 200 201 static void usage(const char *p) 202 { 203 (void)fprintf(stderr, "Usage: %s system_var\n\t%s -a\n" 204 "\t%s path_var pathname\n\t%s -a pathname\n", p, p, p, p); 205 exit(EXIT_FAILURE); 206 } 207 208 static void print_long(const char *name, long val) 209 { 210 if (all) printf("%s = %ld\n", name, val); 211 else printf("%ld\n", val); 212 } 213 214 static void print_ulong(const char *name, unsigned long val) 215 { 216 if (all) printf("%s = %lu\n", name, val); 217 else printf("%lu\n", val); 218 } 219 220 static void print_string(const char *name, const char *val) 221 { 222 if (all) printf("%s = %s\n", name, val); 223 else printf("%s\n", val); 224 } 225 226 static int print_constant(const struct conf_variable *cp, const char *pathname) 227 { 228 print_long(cp->name, cp->value); 229 return 0; 230 } 231 232 static int print_uconstant(const struct conf_variable *cp, const char *pathname) 233 { 234 print_ulong(cp->name, (unsigned long) cp->value); 235 return 0; 236 } 237 238 static int print_sysconf(const struct conf_variable *cp, const char *pathname) 239 { 240 long val; 241 242 errno = 0; 243 if ((val = sysconf((int)cp->value)) == -1) { 244 if (errno != 0) err(EXIT_FAILURE, "sysconf(%ld)", cp->value); 245 return -1; 246 } 247 print_long(cp->name, val); 248 return 0; 249 } 250 251 static int print_confstr(const struct conf_variable *cp, const char *pathname) 252 { 253 size_t len; 254 char *val; 255 256 errno = 0; 257 if ((len = confstr((int)cp->value, NULL, 0)) == 0) goto error; 258 if ((val = malloc(len)) == NULL) err(EXIT_FAILURE, "Can't allocate %zu bytes", len); 259 errno = 0; 260 if (confstr((int)cp->value, val, len) == 0) goto error; 261 print_string(cp->name, val); 262 free(val); 263 return 0; 264 error: 265 if (errno != EINVAL) err(EXIT_FAILURE, "confstr(%ld)", cp->value); 266 return -1; 267 } 268 269 static int print_pathconf(const struct conf_variable *cp, const char *pathname) 270 { 271 long val; 272 273 errno = 0; 274 if ((val = pathconf(pathname, (int)cp->value)) == -1) { 275 if (all && errno == EINVAL) return 0; 276 if (errno != 0) err(EXIT_FAILURE, "pathconf(%s, %ld)", pathname, cp->value); 277 return -1; 278 } 279 print_long(cp->name, val); 280 return 0; 281 } 282 283 typedef int (*handler_t)(const struct conf_variable *cp, const char *pathname); 284 static const handler_t type_handlers[NUM_TYPES] = { 285 [SYSCONF] = print_sysconf, 286 [CONFSTR] = print_confstr, 287 [PATHCONF] = print_pathconf, 288 [CONSTANT] = print_constant, 289 [UCONSTANT] = print_uconstant, 290 }; 291 292 int main(int argc, char **argv) 293 { 294 const char *progname = argv[0]; 295 const struct conf_variable *cp; 296 const char *varname, *pathname; 297 int ch, found = 0; 298 299 (void)setlocale(LC_ALL, ""); 300 while ((ch = getopt(argc, argv, "a")) != -1) { 301 switch (ch) { 302 case 'a': 303 all = 1; 304 break; 305 case '?': 306 default: 307 usage(progname); 308 } 309 } 310 argc -= optind; 311 argv += optind; 312 313 if (!all) { 314 if (argc == 0) 315 usage(progname); 316 varname = argv[0]; 317 argc--; 318 argv++; 319 } else 320 varname = NULL; 321 322 if (argc > 1) 323 usage(progname); 324 pathname = argv[0]; /* may be NULL */ 325 326 for (cp = conf_table; cp->name != NULL; cp++) { 327 if (!all && strcmp(varname, cp->name) != 0) continue; 328 if ((cp->type == PATHCONF) == (pathname != NULL)) { 329 if (type_handlers[cp->type](cp, pathname) < 0) 330 print_string(cp->name, "undefined"); 331 found = 1; 332 } else if (!all) 333 errx(EXIT_FAILURE, "%s: invalid variable type", cp->name); 334 } 335 if (!all && !found) errx(EXIT_FAILURE, "%s: unknown variable", varname); 336 (void)fflush(stdout); 337 return ferror(stdout) ? EXIT_FAILURE : EXIT_SUCCESS; 338 }