util/utils.c

   1 static const char CVSID[] = "$Id: utils.c,v 1.10 2001/12/13 13:27:01 amai Exp $";
   2 /*******************************************************************************
   3 *                                                                              *
   4 * utils.c -- miscellaneous non-GUI routines                                    *
   5 *                                                                              *
   6 *                                                                              *
   7 * This is free software; you can redistribute it and/or modify it under the    *
   8 * terms of the GNU General Public License as published by the Free Software    *
   9 * Foundation; either version 2 of the License, or (at your option) any later   *
  10 * version.                                                                                     *
  11 *                                                                              *
  12 * This software is distributed in the hope that it will be useful, but WITHOUT *
  13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or        *
  14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License        *
  15 * for more details.*                                                           *
  16 *                                                                              *
  17 * You should have received a copy of the GNU General Public License along with *
  18 * software; if not, write to the Free Software Foundation, Inc., 59 Temple     *
  19 * Place, Suite 330, Boston, MA  02111-1307 USA                                   *
  20 *                                                                              *
  21 *******************************************************************************/
  22
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #ifdef VMS
  28 #include <lib$routines.h>
  29 #include ssdef
  30 #include syidef
  31 #include "../util/VMSparam.h"
  32 #include "../util/VMSutils.h"
  33 #endif
  34 #include <sys/types.h>
  35 #include <sys/utsname.h>
  36 #ifdef VMS
  37 #include "vmsparam.h"
  38 #else
  39 #include <sys/param.h>
  40 #endif /*VMS*/
  41 #include <pwd.h>
  42 /* just to get 'Boolean' types defined: */
  43 #include <X11/Xlib.h>
  44
  45 #include "utils.h"
  46
  47
  48 extern const char
  49 *GetCurrentDir(void)
  50 /* return non-NULL value for the current working directory.
  51    If system call fails, provide a fallback value */
  52 {
  53   static char curdir[MAXPATHLEN];
  54
  55   if (!getcwd(curdir, MAXPATHLEN)) {
  56      perror("NEdit: getcwd() fails");
  57      strcpy(curdir, ".");
  58   }
  59   return (curdir);
  60 }
  61
  62
  63 extern const char
  64 *GetHomeDir(void)
  65 /* return a non-NULL value for the user's home directory,
  66    without trailing slash.
  67    We try the  environment var and the system user database. */
  68 {
  69     const char *ptr;
  70     static char homedir[MAXPATHLEN]="";
  71     struct passwd *passwdEntry;
  72     int len;
  73
  74     if (*homedir) {
  75        return homedir;
  76     }
  77     ptr=getenv("HOME");
  78     if (!ptr) {
  79        passwdEntry = getpwuid(getuid());
  80        if (passwdEntry && *(passwdEntry->pw_dir)) {
  81           ptr= passwdEntry->pw_dir;
  82        } else {
  83           /* This is really serious, so just exit. */
  84           perror("NEdit/nc: getpwuid() failed ");
  85           exit(EXIT_FAILURE);
  86        }
  87     }
  88     strncpy(homedir, ptr, sizeof(homedir)-1);
  89     homedir[sizeof(homedir)-1]='\0';
  90     /* Fix trailing slash */
  91     len=strlen(homedir);
  92     if (len>1 && homedir[len-1]=='/') {
  93        homedir[len-1]='\0';
  94     }
  95     return homedir;
  96 }
  97
  98 /*
  99 ** Return a pointer to the username of the current user in a statically
 100 ** allocated string.
 101 */
 102 const char
 103 *GetUserName(void)
 104 {
 105 #ifdef VMS
 106     return cuserid(NULL);
 107 #else
 108     /* cuserid has apparently been dropped from the ansi C standard, and if
 109        strict ansi compliance is turned on (on Sun anyhow, maybe others), calls
 110        to cuserid fail to compile.  Older versions of nedit try to use the
 111        getlogin call first, then if that fails, use getpwuid and getuid.  This
 112        results in the user-name of the original terminal being used, which is
 113        not correct when the user uses the su command.  Now, getpwuid only: */
 114
 115     const struct passwd *passwdEntry;
 116     static char *userName=NULL;
 117
 118     if (userName)
 119        return userName;
 120
 121     passwdEntry = getpwuid(getuid());
 122     if (!passwdEntry) {
 123        /* This is really serious, so just exit. */
 124        perror("NEdit/nc: getpwuid() failed ");
 125        exit(EXIT_FAILURE);
 126     }
 127     userName=malloc(strlen(passwdEntry->pw_name)+1);
 128     strcpy(userName, passwdEntry->pw_name);
 129     return userName;
 130 #endif /* VMS */
 131 }
 132
 133
 134 /*
 135 ** Writes the hostname of the current system in string "hostname".
 136 */
 137 const char
 138 *GetHostName(void)
 139 {
 140     static char hostname[MAXNODENAMELEN+1];
 141     static int  hostnameFound = False;
 142
 143     if (!hostnameFound) {
 144 #ifdef VMS
 145         /* This should be simple, but uname is not supported in the DEC C RTL and
 146            gethostname on VMS depends either on Multinet or UCX.  So use uname
 147            on Unix, and use LIB$GETSYI on VMS. Note the VMS hostname will
 148            be in DECNET format with trailing double colons, e.g. "FNALV1::".    */
 149         int syi_status;
 150         struct dsc$descriptor_s *hostnameDesc;
 151         unsigned long int syiItemCode = SYI$_NODENAME;  /* get Nodename */
 152         unsigned long int unused = 0;
 153         unsigned short int hostnameLen = MAXNODENAMELEN+1;
 154
 155         hostnameDesc = NulStrWrtDesc(hostname, MAXNODENAMELEN+1);
 156         syi_status = lib$getsyi(&syiItemCode, &unused, hostnameDesc, &hostnameLen,
 157                                 0, 0);
 158         if (syi_status != SS$_NORMAL) {
 159             fprintf(stderr, "Error return from lib$getsyi: %d", syi_status);
 160             strcpy(hostname, "VMS");
 161         } else
 162             hostname[hostnameLen] = '\0';
 163         FreeStrDesc(hostnameDesc);
 164 #else
 165         struct utsname nameStruct;
 166         int rc = uname(&nameStruct);
 167         if (rc<0) {
 168             /* Shouldn't ever happen, so we better exit() here */
 169            perror("NEdit/nc: uname() failed ");
 170            exit(EXIT_FAILURE);
 171         }
 172         strcpy(hostname, nameStruct.nodename);
 173 #endif /* VMS */
 174         hostnameFound = True;
 175     }
 176     return hostname;
 177 }
 178
 179
 180 /*
 181 ** Create a path: $HOME/filename
 182 ** Return "" if it doesn't fit into the buffer
 183 */
 184 char
 185 *PrependHome(const char *filename, char *buf, int buflen)
 186 {
 187     const char *homedir;
 188     int home_len, file_len;
 189
 190     homedir=GetHomeDir();
 191     home_len=strlen(homedir);
 192     file_len=strlen(filename);
 193     if ( (home_len+1+file_len)>=buflen ) {
 194        buf[0]='\0';
 195     }
 196     else {
 197        strcpy(buf, homedir);
 198        strcat(buf, "/");
 199        strcat(buf, filename);
 200     }
 201     return buf;
 202 }
 203
 204 extern int Max(int i1, int i2)
 205 {
 206     return i1 >= i2 ? i1 : i2;
 207 }
 208
 209 extern int Min(int i1, int i2)
 210 {
 211     return i1 <= i2 ? i1 : i2;
 212 }
 213
 214 extern int Min3(int i1, int i2, int i3)
 215 {
 216     if (i1 <= i2 && i1 <= i3)
 217         return i1;
 218     return i2 <= i3 ? i2 : i3;
 219 }
 220
 221 extern int Max3(int i1, int i2, int i3)
 222 {
 223     if (i1 >= i2 && i1 >= i3)
 224         return i1;
 225     return i2 >= i3 ? i2 : i3;
 226 }