physmem.c

   1 /* Calculate the size of physical memory.
   2
   3    Copyright (C) 2000, 2001, 2003, 2005, 2006 Free Software
   4    Foundation, Inc.
   5
   6    This program is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 /* Written by Paul Eggert.  */
  20
  21 #include <unistd.h>
  22
  23 #if HAVE_SYS_PSTAT_H
  24 # include <sys/pstat.h>
  25 #endif
  26
  27 #if HAVE_SYS_SYSMP_H
  28 # include <sys/sysmp.h>
  29 #endif
  30
  31 #if HAVE_SYS_SYSINFO_H && HAVE_MACHINE_HAL_SYSINFO_H
  32 # include <sys/sysinfo.h>
  33 # include <machine/hal_sysinfo.h>
  34 #endif
  35
  36 #if HAVE_SYS_TABLE_H
  37 # include <sys/table.h>
  38 #endif
  39
  40 #include <sys/types.h>
  41
  42 #if HAVE_SYS_PARAM_H
  43 # include <sys/param.h>
  44 #endif
  45
  46 #if HAVE_SYS_SYSCTL_H
  47 # include <sys/sysctl.h>
  48 #endif
  49
  50 #if HAVE_SYS_SYSTEMCFG_H
  51 # include <sys/systemcfg.h>
  52 #endif
  53
  54 #ifdef _WIN32
  55 # define WIN32_LEAN_AND_MEAN
  56 # include <windows.h>
  57 /*  MEMORYSTATUSEX is missing from older windows headers, so define
  58     a local replacement.  */
  59 typedef struct
  60 {
  61   DWORD dwLength;
  62   DWORD dwMemoryLoad;
  63   DWORDLONG ullTotalPhys;
  64   DWORDLONG ullAvailPhys;
  65   DWORDLONG ullTotalPageFile;
  66   DWORDLONG ullAvailPageFile;
  67   DWORDLONG ullTotalVirtual;
  68   DWORDLONG ullAvailVirtual;
  69   DWORDLONG ullAvailExtendedVirtual;
  70 } lMEMORYSTATUSEX;
  71 typedef WINBOOL (WINAPI *PFN_MS_EX) (lMEMORYSTATUSEX*);
  72 #endif
  73
  74 #define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
  75
  76 /* Return the total amount of physical memory.  */
  77 double
  78 physmem_total (void)
  79 {
  80 #if defined _SC_PHYS_PAGES && defined _SC_PAGESIZE
  81   { /* This works on linux-gnu, solaris2 and cygwin.  */
  82     double pages = sysconf (_SC_PHYS_PAGES);
  83     double pagesize = sysconf (_SC_PAGESIZE);
  84     if (0 <= pages && 0 <= pagesize)
  85       return pages * pagesize;
  86   }
  87 #endif
  88
  89 #if HAVE_PSTAT_GETSTATIC
  90   { /* This works on hpux11.  */
  91     struct pst_static pss;
  92     if (0 <= pstat_getstatic (&pss, sizeof pss, 1, 0))
  93       {
  94         double pages = pss.physical_memory;
  95         double pagesize = pss.page_size;
  96         if (0 <= pages && 0 <= pagesize)
  97           return pages * pagesize;
  98       }
  99   }
 100 #endif
 101
 102 #if HAVE_SYSMP && defined MP_SAGET && defined MPSA_RMINFO && defined _SC_PAGESIZE
 103   { /* This works on irix6. */
 104     struct rminfo realmem;
 105     if (sysmp (MP_SAGET, MPSA_RMINFO, &realmem, sizeof realmem) == 0)
 106       {
 107         double pagesize = sysconf (_SC_PAGESIZE);
 108         double pages = realmem.physmem;
 109         if (0 <= pages && 0 <= pagesize)
 110           return pages * pagesize;
 111       }
 112   }
 113 #endif
 114
 115 #if HAVE_GETSYSINFO && defined GSI_PHYSMEM
 116   { /* This works on Tru64 UNIX V4/5.  */
 117     int physmem;
 118
 119     if (getsysinfo (GSI_PHYSMEM, (caddr_t) &physmem, sizeof (physmem),
 120                     NULL, NULL, NULL) == 1)
 121       {
 122         double kbytes = physmem;
 123
 124         if (0 <= kbytes)
 125           return kbytes * 1024.0;
 126       }
 127   }
 128 #endif
 129
 130 #if HAVE_SYSCTL && defined HW_PHYSMEM
 131   { /* This works on *bsd and darwin.  */
 132     unsigned int physmem;
 133     size_t len = sizeof physmem;
 134     static int mib[2] = { CTL_HW, HW_PHYSMEM };
 135
 136     if (sysctl (mib, ARRAY_SIZE (mib), &physmem, &len, NULL, 0) == 0
 137         && len == sizeof (physmem))
 138       return (double) physmem;
 139   }
 140 #endif
 141
 142 #if HAVE__SYSTEM_CONFIGURATION
 143   /* This works on AIX.  */
 144   return _system_configuration.physmem;
 145 #endif
 146
 147 #if defined _WIN32
 148   { /* this works on windows */
 149     PFN_MS_EX pfnex;
 150     HMODULE h = GetModuleHandle ("kernel32.dll");
 151
 152     if (!h)
 153       return 0.0;
 154
 155     /*  Use GlobalMemoryStatusEx if available.  */
 156     if ((pfnex = (PFN_MS_EX) GetProcAddress (h, "GlobalMemoryStatusEx")))
 157       {
 158         lMEMORYSTATUSEX lms_ex;
 159         lms_ex.dwLength = sizeof lms_ex;
 160         if (!pfnex (&lms_ex))
 161           return 0.0;
 162         return (double) lms_ex.ullTotalPhys;
 163       }
 164
 165     /*  Fall back to GlobalMemoryStatus which is always available.
 166         but returns wrong results for physical memory > 4GB.  */
 167     else
 168       {
 169         MEMORYSTATUS ms;
 170         GlobalMemoryStatus (&ms);
 171         return (double) ms.dwTotalPhys;
 172       }
 173   }
 174 #endif
 175
 176   /* Guess 64 MB.  It's probably an older host, so guess small.  */
 177   return 64 * 1024 * 1024;
 178 }
 179
 180 /* Return the amount of physical memory available.  */
 181 double
 182 physmem_available (void)
 183 {
 184 #if defined _SC_AVPHYS_PAGES && defined _SC_PAGESIZE
 185   { /* This works on linux-gnu, solaris2 and cygwin.  */
 186     double pages = sysconf (_SC_AVPHYS_PAGES);
 187     double pagesize = sysconf (_SC_PAGESIZE);
 188     if (0 <= pages && 0 <= pagesize)
 189       return pages * pagesize;
 190   }
 191 #endif
 192
 193 #if HAVE_PSTAT_GETSTATIC && HAVE_PSTAT_GETDYNAMIC
 194   { /* This works on hpux11.  */
 195     struct pst_static pss;
 196     struct pst_dynamic psd;
 197     if (0 <= pstat_getstatic (&pss, sizeof pss, 1, 0)
 198         && 0 <= pstat_getdynamic (&psd, sizeof psd, 1, 0))
 199       {
 200         double pages = psd.psd_free;
 201         double pagesize = pss.page_size;
 202         if (0 <= pages && 0 <= pagesize)
 203           return pages * pagesize;
 204       }
 205   }
 206 #endif
 207
 208 #if HAVE_SYSMP && defined MP_SAGET && defined MPSA_RMINFO && defined _SC_PAGESIZE
 209   { /* This works on irix6. */
 210     struct rminfo realmem;
 211     if (sysmp (MP_SAGET, MPSA_RMINFO, &realmem, sizeof realmem) == 0)
 212       {
 213         double pagesize = sysconf (_SC_PAGESIZE);
 214         double pages = realmem.availrmem;
 215         if (0 <= pages && 0 <= pagesize)
 216           return pages * pagesize;
 217       }
 218   }
 219 #endif
 220
 221 #if HAVE_TABLE && defined TBL_VMSTATS
 222   { /* This works on Tru64 UNIX V4/5.  */
 223     struct tbl_vmstats vmstats;
 224
 225     if (table (TBL_VMSTATS, 0, &vmstats, 1, sizeof (vmstats)) == 1)
 226       {
 227         double pages = vmstats.free_count;
 228         double pagesize = vmstats.pagesize;
 229
 230         if (0 <= pages && 0 <= pagesize)
 231           return pages * pagesize;
 232       }
 233   }
 234 #endif
 235
 236 #if HAVE_SYSCTL && defined HW_USERMEM
 237   { /* This works on *bsd and darwin.  */
 238     unsigned int usermem;
 239     size_t len = sizeof usermem;
 240     static int mib[2] = { CTL_HW, HW_USERMEM };
 241
 242     if (sysctl (mib, ARRAY_SIZE (mib), &usermem, &len, NULL, 0) == 0
 243         && len == sizeof (usermem))
 244       return (double) usermem;
 245   }
 246 #endif
 247
 248 #if defined _WIN32
 249   { /* this works on windows */
 250     PFN_MS_EX pfnex;
 251     HMODULE h = GetModuleHandle ("kernel32.dll");
 252
 253     if (!h)
 254       return 0.0;
 255
 256     /*  Use GlobalMemoryStatusEx if available.  */
 257     if ((pfnex = (PFN_MS_EX) GetProcAddress (h, "GlobalMemoryStatusEx")))
 258       {
 259         lMEMORYSTATUSEX lms_ex;
 260         lms_ex.dwLength = sizeof lms_ex;
 261         if (!pfnex (&lms_ex))
 262           return 0.0;
 263         return (double) lms_ex.ullAvailPhys;
 264       }
 265
 266     /*  Fall back to GlobalMemoryStatus which is always available.
 267         but returns wrong results for physical memory > 4GB  */
 268     else
 269       {
 270         MEMORYSTATUS ms;
 271         GlobalMemoryStatus (&ms);
 272         return (double) ms.dwAvailPhys;
 273       }
 274   }
 275 #endif
 276
 277   /* Guess 25% of physical memory.  */
 278   return physmem_total () / 4;
 279 }
 280
 281
 282 #if DEBUG
 283
 284 # include <stdio.h>
 285 # include <stdlib.h>
 286
 287 int
 288 main (void)
 289 {
 290   printf ("%12.f %12.f\n", physmem_total (), physmem_available ());
 291   exit (0);
 292 }
 293
 294 #endif /* DEBUG */
 295
 296 /*
 297 Local Variables:
 298 compile-command: "gcc -DDEBUG -g -O -Wall -W physmem.c"
 299 End:
 300 */