+/*
+ * 'cupsdExec()' - Run a program with the correct environment.
+ *
+ * On Mac OS X, we need to update the CFProcessPath environment variable that
+ * is passed in the environment so the child can access its bundled resources.
+ */
+
+int /* O - exec() status */
+cupsdExec(const char *command, /* I - Full path to program */
+ char **argv) /* I - Command-line arguments */
+{
+#ifdef __APPLE__
+ int i, j; /* Looping vars */
+ char *envp[500], /* Array of environment variables */
+ cfprocesspath[1024], /* CFProcessPath environment variable */
+ linkpath[1024]; /* Link path for symlinks... */
+ int linkbytes; /* Bytes for link path */
+
+
+ /*
+ * Some Mac OS X programs are bundled and need the CFProcessPath environment
+ * variable defined. If the command is a symlink, resolve the link and point
+ * to the resolved location, otherwise, use the command path itself.
+ */
+
+ if ((linkbytes = readlink(command, linkpath, sizeof(linkpath) - 1)) > 0)
+ {
+ /*
+ * Yes, this is a symlink to the actual program, nul-terminate and
+ * use it...
+ */
+
+ linkpath[linkbytes] = '\0';
+
+ if (linkpath[0] == '/')
+ snprintf(cfprocesspath, sizeof(cfprocesspath), "CFProcessPath=%s",
+ linkpath);
+ else
+ snprintf(cfprocesspath, sizeof(cfprocesspath), "CFProcessPath=%s/%s",
+ dirname((char *)command), linkpath);
+ }
+ else
+ snprintf(cfprocesspath, sizeof(cfprocesspath), "CFProcessPath=%s", command);
+
+ envp[0] = cfprocesspath;
+
+ /*
+ * Copy the rest of the environment except for any CFProcessPath that may
+ * already be there...
+ */
+
+ for (i = 1, j = 0;
+ environ[j] && i < (int)(sizeof(envp) / sizeof(envp[0]) - 1);
+ j ++)
+ if (strncmp(environ[j], "CFProcessPath=", 14))
+ envp[i ++] = environ[j];
+
+ envp[i] = NULL;
+
+ /*
+ * Use execve() to run the program...
+ */
+
+ return (execve(command, argv, envp));
+
+#else
+ /*
+ * On other operating systems, just call execv() to use the same environment
+ * variables as the parent...
+ */
+
+ return (execv(command, argv));
+#endif /* __APPLE__ */
+}
+
+
+/*
+ * 'cupsdPipeCommand()' - Read output from a command.
+ */
+
+cups_file_t * /* O - CUPS file or NULL on error */
+cupsdPipeCommand(int *pid, /* O - Process ID or 0 on error */
+ const char *command, /* I - Command to run */
+ char **argv, /* I - Arguments to pass to command */
+ int user) /* I - User to run as or 0 for current */
+{
+ int fds[2]; /* Pipe file descriptors */
+
+
+ /*
+ * First create the pipe...
+ */
+
+ if (pipe(fds))
+ {
+ *pid = 0;
+ return (NULL);
+ }
+
+ /*
+ * Set the "close on exec" flag on each end of the pipe...
+ */
+
+ if (fcntl(fds[0], F_SETFD, fcntl(fds[0], F_GETFD) | FD_CLOEXEC))
+ {
+ close(fds[0]);
+ close(fds[1]);
+
+ *pid = 0;
+
+ return (NULL);
+ }
+
+ if (fcntl(fds[1], F_SETFD, fcntl(fds[1], F_GETFD) | FD_CLOEXEC))
+ {
+ close(fds[0]);
+ close(fds[1]);
+
+ *pid = 0;
+
+ return (NULL);
+ }
+
+ /*
+ * Then run the command...
+ */
+
+ if ((*pid = fork()) < 0)
+ {
+ /*
+ * Unable to fork!
+ */
+
+ *pid = 0;
+ close(fds[0]);
+ close(fds[1]);
+
+ return (NULL);
+ }
+ else if (!*pid)
+ {
+ /*
+ * Child comes here...
+ */
+
+ if (!getuid() && user)
+ setuid(user); /* Run as restricted user */
+
+ close(0); /* </dev/null */
+ open("/dev/null", O_RDONLY);
+
+ close(1); /* >pipe */
+ dup(fds[1]);
+
+ cupsdExec(command, argv);
+ exit(errno);
+ }
+
+ /*
+ * Parent comes here, open the input side of the pipe...
+ */
+
+ close(fds[1]);
+
+ return (cupsFileOpenFd(fds[0], "r"));
+}
+
+