popt/findme.c

   1 /** \ingroup popt
   2  * \file popt/findme.c
   3  */
   4
   5 /* (C) 1998-2002 Red Hat, Inc. -- Licensing details are in the COPYING
   6    file accompanying popt source distributions, available from
   7    ftp://ftp.rpm.org/pub/rpm/dist. */
   8
   9 #include "system.h"
  10 #include "findme.h"
  11
  12 const char * findProgramPath(const char * argv0)
  13 {
  14     char * path = getenv("PATH");
  15     char * pathbuf;
  16     char * start, * chptr;
  17     char * buf;
  18     size_t bufsize;
  19
  20     if (argv0 == NULL) return NULL;     /* XXX can't happen */
  21     /* If there is a / in the argv[0], it has to be an absolute path */
  22     if (strchr(argv0, '/'))
  23         return xstrdup(argv0);
  24
  25     if (path == NULL) return NULL;
  26
  27     bufsize = strlen(path) + 1;
  28     start = pathbuf = alloca(bufsize);
  29     if (pathbuf == NULL) return NULL;   /* XXX can't happen */
  30     strlcpy(pathbuf, path, bufsize);
  31     bufsize += sizeof "/" - 1 + strlen(argv0);
  32     buf = malloc(bufsize);
  33     if (buf == NULL) return NULL;       /* XXX can't happen */
  34
  35     chptr = NULL;
  36     /*@-branchstate@*/
  37     do {
  38         if ((chptr = strchr(start, ':')))
  39             *chptr = '\0';
  40         snprintf(buf, bufsize, "%s/%s", start, argv0);
  41
  42         if (!access(buf, X_OK))
  43             return buf;
  44
  45         if (chptr)
  46             start = chptr + 1;
  47         else
  48             start = NULL;
  49     } while (start && *start);
  50     /*@=branchstate@*/
  51
  52     free(buf);
  53
  54     return NULL;
  55 }