/*
 * Copyright 1999-2003 Gentoo Technologies, Inc.
 * Distributed under the terms of the GNU General Public License v2
 * Author: Martin Schlemmer <azarah@gentoo.org>
 * $Header: /home/cvsroot/gentoo-x86/sys-devel/gcc-config/files/wrapper.c,v 1.3 2003/01/15 22:28:10 azarah Exp $
 */

#define _REENTRANT
#define _GNU_SOURCE

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <unistd.h>
#include <wait.h>
#include <libgen.h>
#include <string.h>


int main(int argc, char **argv)
{
  FILE *inpipe = NULL;
  struct stat sbuf;
  char wrapperbin[MAXPATHLEN + 1], wrapfullname[MAXPATHLEN + 1];
  char *wrappername = NULL;
  char *buffer = NULL, *token = NULL, *tmpstr = NULL, *state = NULL;
  int ret = 0;
  char *newargs[argc + 1];

  wrapperbin[0] = '\0';

  /* What should we find ? */
  wrappername = strdupa(basename(argv[0]));

  /* cc calls gcc ... */
  if (0 == strcmp(wrappername, "cc"))
    sprintf(wrappername, "%s", "gcc");

  buffer = (char *) malloc(16);
  /* Check if we're supposed to use distcc or not... */
  sprintf(buffer, "/etc/.usedistcc");
  ret = stat(buffer, &sbuf);
  if ((0 == ret) && (sbuf.st_mode & S_IFREG))
    {
      /* Using distcc, strip the path..
       * Assumes that distccd server's are using restricted PATH's
       */
      argv[0] = wrappername;
      /* Pull in cached gcc-config --get-path-bin from last
       * source /etc/profile...
       */
      if (buffer)
        {
          free(buffer);
          buffer = NULL;
        }

      if (getenv("GCCBINPATH"))
        {
          buffer = strdup((char *) getenv("GCCBINPATH"));
          setenv("PATH", buffer, 1);
      } else {
/*  Just get it from gcc-config instead..
          printf("Oops! GCCBINPATH not set. Please make sure that you have\n"
                 "the following line in your /etc/profile\n"
                 "[ -f /etc/profile.d/distcc ] && source /etc/profile.d/distcc\n");
          exit(1);
*/
          /* GCCBINPATH not set.. get it from gcc-config */

          inpipe = popen("/usr/bin/gcc-config --get-bin-path", "r");
          if (NULL == inpipe)
            {
              fprintf(stderr, "Oops! GCCBINPATH not set and could not run /usr/bin/gcc-config!\n"
                     "Please make sure that you have the following line in your /etc/profile\n"
                     "[ -f /etc/profile.d/distcc ] && source /etc/profile.d/distcc\n");
              exit(1);
            }

          buffer = (char *)malloc(MAXPATHLEN + 1);
          if (fgets(buffer, MAXPATHLEN, inpipe) == 0)
            {
              fprintf(stderr, "Could not get compiler binary path!\n");

              if (buffer)
                {
                  free(buffer);
                  buffer = NULL;
                }

              pclose(inpipe);

              exit(1);
            }
          /* just use wrapfullname to hold path temp */
          sscanf(buffer, "%s", wrapfullname);
          setenv("PATH", wrapfullname, 1);
          pclose(inpipe);
        }

      int j = 1;

      while (j <= argc)
        {
          newargs[j] = argv[j - 1];
          j++;
        }

      newargs[0] = "/usr/bin/distcc";

      /* Ok, do it ... */
      if (execv(newargs[0], newargs) < 0)
        {
          fprintf(stderr, "Could not run/locate %s!\n", newargs[0]);
          exit(1);
        }

  } else {

      /* What is the full name of our wrapper? */
      snprintf(wrapfullname, strlen("/usr/bin/") + strlen(wrappername) + 1,
               "%s%s", "/usr/bin/", wrappername);

      if (buffer)
        {
          free(buffer);
          buffer = NULL;
        }

      buffer = strdup((char *) getenv("PATH"));
      token = strtok_r(buffer, ":", &state);
      ret = 0;
      /* Find the first file with suitable name in PATH */
      while ((NULL != token) && (strlen(token) > 0))
        {

          tmpstr = (char *) malloc(strlen(token) + strlen(wrappername) + 2);
          snprintf(tmpstr, strlen(token) + strlen(wrappername) + 2,
                   "%s/%s", token, wrappername);

          /* Does it exist and is a file? */
          ret = stat(tmpstr, &sbuf);
          /* It exists, and are not our wrapper, and its not in /usr/bin ... */
          if ((0 == ret) && (sbuf.st_mode & S_IFREG) &&
              (0 != strcmp(tmpstr, wrapfullname))
              && (0 == strstr(tmpstr, "/usr/bin")))
            {

              strncpy(wrapperbin, tmpstr, MAXPATHLEN);

              if (tmpstr)
                {
                  free(tmpstr);
                  tmpstr = NULL;
                }

              break;
            }

          token = strtok_r(NULL, ":", &state);
        }

      if (buffer)
        {
          free(buffer);
          buffer = NULL;
        }
      /* Did we get a valid binary to execute? */
      if (wrapperbin[0] == '\0')
        {
          /* It is our wrapper, so get the CC path, and execute the real binary in
           * there ... */

          inpipe = popen("/usr/bin/gcc-config --get-bin-path", "r");
          if (NULL == inpipe)
            {
              fprintf(stderr, "Could not run /usr/bin/gcc-config!\n");
              exit(1);
            }

          buffer = (char *)malloc(MAXPATHLEN + 1);

          if (fgets(buffer, MAXPATHLEN, inpipe) == 0)
            {
              fprintf(stderr, "Could not get compiler binary path!\n");

              if (buffer)
                {
                  free(buffer);
                  buffer = NULL;
                }

              pclose(inpipe);

              exit(1);
            }

          sscanf(buffer, "%s", wrapperbin);
          strncat(wrapperbin, "/", MAXPATHLEN - strlen(wrapperbin));
          strncat(wrapperbin, wrappername, MAXPATHLEN - strlen(wrapperbin));

          pclose(inpipe);

          if (buffer)
            {
              free(buffer);
              buffer = NULL;
            }
        }

      /* Set argv[0] to the correct binary, else gcc do not find internal
       * headers, etc (bug #8132). */
      argv[0] = wrapperbin;

      /* Ok, do it ... */
      if (execv(argv[0], argv) < 0)
        {
          fprintf(stderr, "Could not run/locate %s!\n", argv[0]);
          exit(1);
        }
    }

  return 0;
}