1 /* Calculate the size of physical memory.
2 
3    Copyright (C) 2000-2001, 2003, 2005-2006, 2009-2018 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 <https://www.gnu.org/licenses/>.  */
18 
19 /* Written by Paul Eggert.  */
20 
21 #include <config.h>
22 
23 #include "physmem.h"
24 
25 #include <unistd.h>
26 
27 #if HAVE_SYS_PSTAT_H
28 # include <sys/pstat.h>
29 #endif
30 
31 #if HAVE_SYS_SYSMP_H
32 # include <sys/sysmp.h>
33 #endif
34 
35 #if HAVE_SYS_SYSINFO_H
36 # include <sys/sysinfo.h>
37 #endif
38 
39 #if HAVE_MACHINE_HAL_SYSINFO_H
40 # include <machine/hal_sysinfo.h>
41 #endif
42 
43 #if HAVE_SYS_TABLE_H
44 # include <sys/table.h>
45 #endif
46 
47 #include <sys/types.h>
48 
49 #if HAVE_SYS_PARAM_H
50 # include <sys/param.h>
51 #endif
52 
53 #if HAVE_SYS_SYSCTL_H
54 # include <sys/sysctl.h>
55 #endif
56 
57 #if HAVE_SYS_SYSTEMCFG_H
58 # include <sys/systemcfg.h>
59 #endif
60 
61 #ifdef _WIN32
62 # define WIN32_LEAN_AND_MEAN
63 # include <windows.h>
64 /*  MEMORYSTATUSEX is missing from older windows headers, so define
65     a local replacement.  */
66 typedef struct
67 {
68   DWORD dwLength;
69   DWORD dwMemoryLoad;
70   DWORDLONG ullTotalPhys;
71   DWORDLONG ullAvailPhys;
72   DWORDLONG ullTotalPageFile;
73   DWORDLONG ullAvailPageFile;
74   DWORDLONG ullTotalVirtual;
75   DWORDLONG ullAvailVirtual;
76   DWORDLONG ullAvailExtendedVirtual;
77 } lMEMORYSTATUSEX;
78 typedef WINBOOL (WINAPI *PFN_MS_EX) (lMEMORYSTATUSEX*);
79 #endif
80 
81 #define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
82 
83 /* Return the total amount of physical memory.  */
84 double
physmem_total(void)85 physmem_total (void)
86 {
87 #if defined _SC_PHYS_PAGES && defined _SC_PAGESIZE
88   { /* This works on linux-gnu, solaris2 and cygwin.  */
89     double pages = sysconf (_SC_PHYS_PAGES);
90     double pagesize = sysconf (_SC_PAGESIZE);
91     if (0 <= pages && 0 <= pagesize)
92       return pages * pagesize;
93   }
94 #endif
95 
96 #if HAVE_SYSINFO && HAVE_STRUCT_SYSINFO_MEM_UNIT
97   { /* This works on linux.  */
98     struct sysinfo si;
99     if (sysinfo(&si) == 0)
100       return (double) si.totalram * si.mem_unit;
101   }
102 #endif
103 
104 #if HAVE_PSTAT_GETSTATIC
105   { /* This works on hpux11.  */
106     struct pst_static pss;
107     if (0 <= pstat_getstatic (&pss, sizeof pss, 1, 0))
108       {
109         double pages = pss.physical_memory;
110         double pagesize = pss.page_size;
111         if (0 <= pages && 0 <= pagesize)
112           return pages * pagesize;
113       }
114   }
115 #endif
116 
117 #if HAVE_SYSMP && defined MP_SAGET && defined MPSA_RMINFO && defined _SC_PAGESIZE
118   { /* This works on irix6. */
119     struct rminfo realmem;
120     if (sysmp (MP_SAGET, MPSA_RMINFO, &realmem, sizeof realmem) == 0)
121       {
122         double pagesize = sysconf (_SC_PAGESIZE);
123         double pages = realmem.physmem;
124         if (0 <= pages && 0 <= pagesize)
125           return pages * pagesize;
126       }
127   }
128 #endif
129 
130 #if HAVE_GETSYSINFO && defined GSI_PHYSMEM
131   { /* This works on Tru64 UNIX V4/5.  */
132     int physmem;
133 
134     if (getsysinfo (GSI_PHYSMEM, (caddr_t) &physmem, sizeof (physmem),
135                     NULL, NULL, NULL) == 1)
136       {
137         double kbytes = physmem;
138 
139         if (0 <= kbytes)
140           return kbytes * 1024.0;
141       }
142   }
143 #endif
144 
145 #if HAVE_SYSCTL && defined HW_PHYSMEM
146   { /* This works on *bsd and darwin.  */
147     unsigned int physmem;
148     size_t len = sizeof physmem;
149     static int mib[2] = { CTL_HW, HW_PHYSMEM };
150 
151     if (sysctl (mib, ARRAY_SIZE (mib), &physmem, &len, NULL, 0) == 0
152         && len == sizeof (physmem))
153       return (double) physmem;
154   }
155 #endif
156 
157 #if HAVE__SYSTEM_CONFIGURATION
158   /* This works on AIX.  */
159   return _system_configuration.physmem;
160 #endif
161 
162 #if defined _WIN32
163   { /* this works on windows */
164     PFN_MS_EX pfnex;
165     HMODULE h = GetModuleHandle ("kernel32.dll");
166 
167     if (!h)
168       return 0.0;
169 
170     /*  Use GlobalMemoryStatusEx if available.  */
171     if ((pfnex = (PFN_MS_EX) GetProcAddress (h, "GlobalMemoryStatusEx")))
172       {
173         lMEMORYSTATUSEX lms_ex;
174         lms_ex.dwLength = sizeof lms_ex;
175         if (!pfnex (&lms_ex))
176           return 0.0;
177         return (double) lms_ex.ullTotalPhys;
178       }
179 
180     /*  Fall back to GlobalMemoryStatus which is always available.
181         but returns wrong results for physical memory > 4GB.  */
182     else
183       {
184         MEMORYSTATUS ms;
185         GlobalMemoryStatus (&ms);
186         return (double) ms.dwTotalPhys;
187       }
188   }
189 #endif
190 
191   /* Guess 64 MB.  It's probably an older host, so guess small.  */
192   return 64 * 1024 * 1024;
193 }
194 
195 /* Return the amount of physical memory available.  */
196 double
physmem_available(void)197 physmem_available (void)
198 {
199 #if defined _SC_AVPHYS_PAGES && defined _SC_PAGESIZE
200   { /* This works on linux-gnu, solaris2 and cygwin.  */
201     double pages = sysconf (_SC_AVPHYS_PAGES);
202     double pagesize = sysconf (_SC_PAGESIZE);
203     if (0 <= pages && 0 <= pagesize)
204       return pages * pagesize;
205   }
206 #endif
207 
208 #if HAVE_SYSINFO && HAVE_STRUCT_SYSINFO_MEM_UNIT
209   { /* This works on linux.  */
210     struct sysinfo si;
211     if (sysinfo(&si) == 0)
212       return ((double) si.freeram + si.bufferram) * si.mem_unit;
213   }
214 #endif
215 
216 #if HAVE_PSTAT_GETSTATIC && HAVE_PSTAT_GETDYNAMIC
217   { /* This works on hpux11.  */
218     struct pst_static pss;
219     struct pst_dynamic psd;
220     if (0 <= pstat_getstatic (&pss, sizeof pss, 1, 0)
221         && 0 <= pstat_getdynamic (&psd, sizeof psd, 1, 0))
222       {
223         double pages = psd.psd_free;
224         double pagesize = pss.page_size;
225         if (0 <= pages && 0 <= pagesize)
226           return pages * pagesize;
227       }
228   }
229 #endif
230 
231 #if HAVE_SYSMP && defined MP_SAGET && defined MPSA_RMINFO && defined _SC_PAGESIZE
232   { /* This works on irix6. */
233     struct rminfo realmem;
234     if (sysmp (MP_SAGET, MPSA_RMINFO, &realmem, sizeof realmem) == 0)
235       {
236         double pagesize = sysconf (_SC_PAGESIZE);
237         double pages = realmem.availrmem;
238         if (0 <= pages && 0 <= pagesize)
239           return pages * pagesize;
240       }
241   }
242 #endif
243 
244 #if HAVE_TABLE && defined TBL_VMSTATS
245   { /* This works on Tru64 UNIX V4/5.  */
246     struct tbl_vmstats vmstats;
247 
248     if (table (TBL_VMSTATS, 0, &vmstats, 1, sizeof (vmstats)) == 1)
249       {
250         double pages = vmstats.free_count;
251         double pagesize = vmstats.pagesize;
252 
253         if (0 <= pages && 0 <= pagesize)
254           return pages * pagesize;
255       }
256   }
257 #endif
258 
259 #if HAVE_SYSCTL && defined HW_USERMEM
260   { /* This works on *bsd and darwin.  */
261     unsigned int usermem;
262     size_t len = sizeof usermem;
263     static int mib[2] = { CTL_HW, HW_USERMEM };
264 
265     if (sysctl (mib, ARRAY_SIZE (mib), &usermem, &len, NULL, 0) == 0
266         && len == sizeof (usermem))
267       return (double) usermem;
268   }
269 #endif
270 
271 #if defined _WIN32
272   { /* this works on windows */
273     PFN_MS_EX pfnex;
274     HMODULE h = GetModuleHandle ("kernel32.dll");
275 
276     if (!h)
277       return 0.0;
278 
279     /*  Use GlobalMemoryStatusEx if available.  */
280     if ((pfnex = (PFN_MS_EX) GetProcAddress (h, "GlobalMemoryStatusEx")))
281       {
282         lMEMORYSTATUSEX lms_ex;
283         lms_ex.dwLength = sizeof lms_ex;
284         if (!pfnex (&lms_ex))
285           return 0.0;
286         return (double) lms_ex.ullAvailPhys;
287       }
288 
289     /*  Fall back to GlobalMemoryStatus which is always available.
290         but returns wrong results for physical memory > 4GB  */
291     else
292       {
293         MEMORYSTATUS ms;
294         GlobalMemoryStatus (&ms);
295         return (double) ms.dwAvailPhys;
296       }
297   }
298 #endif
299 
300   /* Guess 25% of physical memory.  */
301   return physmem_total () / 4;
302 }
303 
304 
305 #if DEBUG
306 
307 # include <stdio.h>
308 # include <stdlib.h>
309 
310 int
main(void)311 main (void)
312 {
313   printf ("%12.f %12.f\n", physmem_total (), physmem_available ());
314   exit (0);
315 }
316 
317 #endif /* DEBUG */
318 
319 /*
320 Local Variables:
321 compile-command: "gcc -DDEBUG -g -O -Wall -W physmem.c"
322 End:
323 */
324