Actual source code: grpath.c

  1: #define PETSC_DLL

 3:  #include petscsys.h
  4: #if defined(PETSC_HAVE_PWD_H)
  5: #include <pwd.h>
  6: #endif
  7: #include <ctype.h>
  8: #include <sys/types.h>
  9: #include <sys/stat.h>
 10: #if defined(PETSC_HAVE_UNISTD_H)
 11: #include <unistd.h>
 12: #endif
 13: #if defined(PETSC_HAVE_STDLIB_H)
 14: #include <stdlib.h>
 15: #endif
 16: #if defined(PETSC_HAVE_SYS_UTSNAME_H)
 17: #include <sys/utsname.h>
 18: #endif
 19: #if defined(PETSC_HAVE_SYS_SYSTEMINFO_H)
 20: #include <sys/systeminfo.h>
 21: #endif

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

 28:    Not Collective

 30:    Input Parameter:
 31: .  path - path to resolve

 33:    Output Parameter:
 34: .  rpath - resolved path

 36:    Level: developer

 38:    Notes: 
 39:    rpath is assumed to be of length PETSC_MAX_PATH_LEN.

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

 47:    Concepts: real path
 48:    Concepts: path^real

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

 64: #if defined(PETSC_HAVE_REALPATH)
 65:   realpath(path,rpath);
 66: #elif defined(PETSC_HAVE_READLINK)
 67:   /* Algorithm: we move through the path, replacing links with the real paths.   */
 68:   PetscStrcpy(rpath,path);
 69:   PetscStrlen(rpath,&N);
 70:   while (N) {
 71:     PetscStrncpy(tmp1,rpath,N);
 72:     tmp1[N] = 0;
 73:     n = readlink(tmp1,tmp3,PETSC_MAX_PATH_LEN);
 74:     if (n > 0) {
 75:       tmp3[n] = 0; /* readlink does not automatically add 0 to string end */
 76:       if (tmp3[0] != '/') {
 77:         PetscStrchr(tmp1,'/',&tmp2);
 78:         PetscStrlen(tmp1,&len1);
 79:         PetscStrlen(tmp2,&len2);
 80:         m    = len1 - len2;
 81:         PetscStrncpy(tmp4,tmp1,m);
 82:         tmp4[m] = 0;
 83:         PetscStrlen(tmp4,&len);
 84:         PetscStrncat(tmp4,"/",PETSC_MAX_PATH_LEN - len);
 85:         PetscStrlen(tmp4,&len);
 86:         PetscStrncat(tmp4,tmp3,PETSC_MAX_PATH_LEN - len);
 87:         PetscGetRealPath(tmp4,rpath);
 88:         PetscStrlen(rpath,&len);
 89:         PetscStrncat(rpath,path+N,PETSC_MAX_PATH_LEN - len);
 90:       } else {
 91:         PetscGetRealPath(tmp3,tmp1);
 92:         PetscStrncpy(rpath,tmp1,PETSC_MAX_PATH_LEN);
 93:         PetscStrlen(rpath,&len);
 94:         PetscStrncat(rpath,path+N,PETSC_MAX_PATH_LEN - len);
 95:       }
 96:       return(0);
 97:     }
 98:     PetscStrchr(tmp1,'/',&tmp2);
 99:     if (tmp2) {
100:       PetscStrlen(tmp1,&len1);
101:       PetscStrlen(tmp2,&len2);
102:       N    = len1 - len2;
103:     } else {
104:       PetscStrlen(tmp1,&N);
105:     }
106:   }
107:   PetscStrncpy(rpath,path,PETSC_MAX_PATH_LEN);
108: #else /* Just punt */
109:   PetscStrcpy(rpath,path);
110: #endif

112:   /* remove garbage some automounters put at the beginning of the path */
113:   PetscStrncmp("/tmp_mnt/",rpath,9,&flg);
114:   if (flg) {
115:     PetscStrcpy(tmp3,rpath + 8);
116:     PetscStrcpy(rpath,tmp3);
117:   }
118:   return(0);
119: }