xref: /petsc/src/sys/utils/fhost.c (revision 74df5e01f481fb3fe90b32c3b4345ef0122eb3ce)
1 #define PETSC_DESIRE_FEATURE_TEST_MACROS /* for getdomainname() */
2 /*
3       Code for manipulating files.
4 */
5 #include <petscsys.h>
6 #if defined(PETSC_HAVE_SYS_UTSNAME_H)
7   #include <sys/utsname.h>
8 #endif
9 #if defined(PETSC_HAVE_WINDOWS_H)
10   #include <windows.h>
11 #endif
12 #if defined(PETSC_HAVE_SYS_SYSTEMINFO_H)
13   #include <sys/systeminfo.h>
14 #endif
15 #if defined(PETSC_HAVE_UNISTD_H)
16   #include <unistd.h>
17 #endif
18 #if defined(PETSC_HAVE_NETDB_H)
19   #include <netdb.h>
20 #endif
21 #include <errno.h>
22 
23 /*@C
24   PetscGetHostName - Returns the name of the host. This attempts to
25   return the entire Internet name. It may not return the same name
26   as `MPI_Get_processor_name()`.
27 
28   Not Collective
29 
30   Input Parameter:
31 . nlen - length of name
32 
33   Output Parameter:
34 . name - contains host name.  Must be long enough to hold the name
35            This is the fully qualified name, including the domain.
36 
37   Level: developer
38 
39   Fortran Note:
40 .vb
41   character*(128) name
42   call PetscGetHostName(name,ierr)
43 .ve
44 
45 .seealso: `PetscGetUserName()`, `PetscGetArchType()`
46 @*/
47 PetscErrorCode PetscGetHostName(char name[], size_t nlen)
48 {
49   char *domain = NULL;
50 #if defined(PETSC_HAVE_UNAME) && !defined(PETSC_HAVE_GETCOMPUTERNAME)
51   struct utsname utname;
52 #endif
53 
54   PetscFunctionBegin;
55 #if defined(PETSC_HAVE_GETCOMPUTERNAME)
56   {
57     size_t nnlen = nlen;
58 
59     GetComputerName((LPTSTR)name, (LPDWORD)(&nnlen));
60   }
61 #elif defined(PETSC_HAVE_UNAME)
62   // According to IEEE Std 1003.1-1988 ("POSIX.1") and 1003.1-2024, upon successful completion, uname returns
63   // a non-negative value. Otherwise, -1 shall be returned and errno set to indicate the error.
64   PetscCheck(uname(&utname) != -1, PETSC_COMM_SELF, PETSC_ERR_SYS, "uname() due to \"%s\"", strerror(errno));
65   PetscCall(PetscStrncpy(name, utname.nodename, nlen));
66 #elif defined(PETSC_HAVE_GETHOSTNAME)
67   PetscCheck(!gethostname(name, nlen), PETSC_COMM_SELF, PETSC_ERR_SYS, "gethostname() due to \"%s\"", strerror(errno));
68 #endif
69   /* if there was not enough room then system call will not null terminate name */
70   name[nlen - 1] = 0;
71 
72   /* See if this name includes the domain */
73   PetscCall(PetscStrchr(name, '.', &domain));
74   if (!domain) {
75     size_t l, ll;
76 
77     PetscCall(PetscStrlen(name, &l));
78     if (l == nlen - 1) PetscFunctionReturn(PETSC_SUCCESS);
79     name[l++] = '.';
80     name[l]   = 0;
81 #if defined(PETSC_HAVE_GETDOMAINNAME)
82     PetscCheck(!getdomainname(name + l, (int)(nlen - l)), PETSC_COMM_SELF, PETSC_ERR_SYS, "getdomainname() due to \"%s\"", strerror(errno));
83 #endif
84     /* check if domain name is not a dnsdomainname and nuke it */
85     PetscCall(PetscStrlen(name, &ll));
86     if (ll > 4) {
87       const char *suffixes[] = {".edu", ".com", ".net", ".org", ".mil", NULL};
88       PetscInt    index;
89 
90       PetscCall(PetscStrendswithwhich(name, suffixes, &index));
91       if (!suffixes[index]) {
92         PetscCall(PetscInfo(NULL, "Rejecting domainname, likely is NIS %s\n", name));
93         name[l - 1] = 0;
94       }
95     }
96   }
97   PetscFunctionReturn(PETSC_SUCCESS);
98 }
99