Actual source code: grpath.c

petsc-3.4.5 2014-06-29
  2: #include <petscsys.h>
  3: #if defined(PETSC_HAVE_PWD_H)
  4: #include <pwd.h>
  5: #endif
  6: #include <ctype.h>
  7: #include <sys/stat.h>
  8: #if defined(PETSC_HAVE_UNISTD_H)
  9: #include <unistd.h>
 10: #endif
 11: #if defined(PETSC_HAVE_SYS_UTSNAME_H)
 12: #include <sys/utsname.h>
 13: #endif
 14: #if defined(PETSC_HAVE_SYS_SYSTEMINFO_H)
 15: #include <sys/systeminfo.h>
 16: #endif

 20: /*@C
 21:    PetscGetRealPath - Get the path without symbolic links etc. and in absolute form.

 23:    Not Collective

 25:    Input Parameter:
 26: .  path - path to resolve

 28:    Output Parameter:
 29: .  rpath - resolved path

 31:    Level: developer

 33:    Notes:
 34:    rpath is assumed to be of length PETSC_MAX_PATH_LEN.

 36:    Systems that use the automounter often generate absolute paths
 37:    of the form "/tmp_mnt....".  However, the automounter will fail to
 38:    mount this path if it is not already mounted, so we remove this from
 39:    the head of the line.  This may cause problems if, for some reason,
 40:    /tmp_mnt is valid and not the result of the automounter.

 42:    Concepts: real path
 43:    Concepts: path^real

 45: .seealso: PetscGetFullPath()
 46: @*/
 47: PetscErrorCode  PetscGetRealPath(const char path[],char rpath[])
 48: {
 50:   char           tmp3[PETSC_MAX_PATH_LEN];
 51:   PetscBool      flg;
 52: #if !defined(PETSC_HAVE_REALPATH) && defined(PETSC_HAVE_READLINK)
 53:   char           tmp1[PETSC_MAX_PATH_LEN],tmp4[PETSC_MAX_PATH_LEN],*tmp2;
 54:   size_t         N,len,len1,len2;
 55:   int            n,m;
 56: #endif

 59: #if defined(PETSC_HAVE_REALPATH)
 60:   if (!realpath(path,rpath)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_LIB,"realpath()");
 61: #elif defined(PETSC_HAVE_READLINK)
 62:   /* Algorithm: we move through the path, replacing links with the real paths.   */
 63:   PetscStrcpy(rpath,path);
 64:   PetscStrlen(rpath,&N);
 65:   while (N) {
 66:     PetscStrncpy(tmp1,rpath,N);
 67:     tmp1[N] = 0;
 68:     n       = readlink(tmp1,tmp3,PETSC_MAX_PATH_LEN);
 69:     if (n > 0) {
 70:       tmp3[n] = 0; /* readlink does not automatically add 0 to string end */
 71:       if (tmp3[0] != '/') {
 72:         PetscStrchr(tmp1,'/',&tmp2);
 73:         PetscStrlen(tmp1,&len1);
 74:         PetscStrlen(tmp2,&len2);
 75:         m       = len1 - len2;
 76:         PetscStrncpy(tmp4,tmp1,m);
 77:         tmp4[m] = 0;
 78:         PetscStrlen(tmp4,&len);
 79:         PetscStrncat(tmp4,"/",PETSC_MAX_PATH_LEN - len);
 80:         PetscStrlen(tmp4,&len);
 81:         PetscStrncat(tmp4,tmp3,PETSC_MAX_PATH_LEN - len);
 82:         PetscGetRealPath(tmp4,rpath);
 83:         PetscStrlen(rpath,&len);
 84:         PetscStrncat(rpath,path+N,PETSC_MAX_PATH_LEN - len);
 85:       } else {
 86:         PetscGetRealPath(tmp3,tmp1);
 87:         PetscStrncpy(rpath,tmp1,PETSC_MAX_PATH_LEN);
 88:         PetscStrlen(rpath,&len);
 89:         PetscStrncat(rpath,path+N,PETSC_MAX_PATH_LEN - len);
 90:       }
 91:       return(0);
 92:     }
 93:     PetscStrchr(tmp1,'/',&tmp2);
 94:     if (tmp2) {
 95:       PetscStrlen(tmp1,&len1);
 96:       PetscStrlen(tmp2,&len2);
 97:       N    = len1 - len2;
 98:     } else {
 99:       PetscStrlen(tmp1,&N);
100:     }
101:   }
102:   PetscStrncpy(rpath,path,PETSC_MAX_PATH_LEN);
103: #else /* Just punt */
104:   PetscStrcpy(rpath,path);
105: #endif

107:   /* remove garbage some automounters put at the beginning of the path */
108:   PetscStrncmp("/tmp_mnt/",rpath,9,&flg);
109:   if (flg) {
110:     PetscStrcpy(tmp3,rpath + 8);
111:     PetscStrcpy(rpath,tmp3);
112:   }
113:   return(0);
114: }