+ opt = find_option(option);
+ if (opt == NULL)
+ return 0;
+ while (opt->flags & OPT_PRIOSUB)
+ --opt;
+ if ((opt->flags & OPT_PRIO) && priority < opt->priority)
+ return 0;
+ opt->priority = priority;
+ opt->source = source;
+ opt->winner = -1;
+ return 1;
+}
+
+/*
+ * n_arguments - tell how many arguments an option takes
+ */
+static int
+n_arguments(struct option *opt)
+{
+ return (opt->type == o_bool || opt->type == o_special_noarg
+ || (opt->flags & OPT_NOARG))? 0: 1;
+}
+
+/*
+ * add_options - add a list of options to the set we grok.
+ */
+void
+ppp_add_options(struct option *opt)
+{
+ struct option_list *list;
+
+ list = malloc(sizeof(*list));
+ if (list == 0)
+ novm("option list entry");
+ list->options = opt;
+ list->next = extra_options;
+ extra_options = list;
+}
+
+/*
+ * check_options - check that options are valid and consistent.
+ */
+void
+check_options(void)
+{
+ if (logfile_fd >= 0 && logfile_fd != log_to_fd)
+ close(logfile_fd);
+}
+
+/*
+ * print_option - print out an option and its value
+ */
+static void
+print_option(struct option *opt, struct option *mainopt, printer_func printer, void *arg)
+{
+ int i, v;
+ char *p;
+
+ if (opt->flags & OPT_NOPRINT)
+ return;
+ switch (opt->type) {
+ case o_bool:
+ v = opt->flags & OPT_VALUE;
+ if (*(bool *)opt->addr != v)
+ /* this can happen legitimately, e.g. lock
+ option turned off for default device */
+ break;
+ printer(arg, "%s", opt->name);
+ break;
+ case o_int:
+ v = opt->flags & OPT_VALUE;
+ if (v >= 128)
+ v -= 256;
+ i = *(int *)opt->addr;
+ if (opt->flags & OPT_NOARG) {
+ printer(arg, "%s", opt->name);
+ if (i != v) {
+ if (opt->flags & OPT_INC) {
+ for (; i > v; i -= v)
+ printer(arg, " %s", opt->name);
+ } else
+ printer(arg, " # oops: %d not %d\n",
+ i, v);
+ }
+ } else {
+ printer(arg, "%s %d", opt->name, i);
+ }
+ break;
+ case o_uint32:
+ printer(arg, "%s", opt->name);
+ if ((opt->flags & OPT_NOARG) == 0)
+ printer(arg, " %x", *(u_int32_t *)opt->addr);
+ break;
+
+ case o_string:
+ if (opt->flags & OPT_HIDE) {
+ p = "??????";
+ } else {
+ p = (char *) opt->addr;
+ if ((opt->flags & OPT_STATIC) == 0)
+ p = *(char **)p;
+ }
+ printer(arg, "%s %q", opt->name, p);
+ break;
+
+ case o_special:
+ case o_special_noarg:
+ case o_wild:
+ if (opt->type != o_wild) {
+ printer(arg, "%s", opt->name);
+ if (n_arguments(opt) == 0)
+ break;
+ printer(arg, " ");
+ }
+ if (opt->flags & OPT_A2PRINTER) {
+ void (*oprt)(struct option *, printer_func, void *);
+ oprt = (void (*)(struct option *, printer_func, void *))
+ opt->addr2;
+ (*oprt)(opt, printer, arg);
+ } else if (opt->flags & OPT_A2STRVAL) {
+ p = (char *) opt->addr2;
+ if ((opt->flags & OPT_STATIC) == 0)
+ p = *(char **)p;
+ printer(arg, "%q", p);
+ } else if (opt->flags & OPT_A2LIST) {
+ struct option_value *ovp;
+
+ ovp = (struct option_value *) opt->addr2;
+ for (;;) {
+ printer(arg, "%q", ovp->value);
+ if ((ovp = ovp->next) == NULL)
+ break;
+ printer(arg, "\t\t# (from %s)\n%s ",
+ ovp->source, opt->name);
+ }
+ } else {
+ printer(arg, "xxx # [don't know how to print value]");
+ }
+ break;
+
+ default:
+ printer(arg, "# %s value (type %d\?\?)", opt->name, opt->type);
+ break;
+ }
+ printer(arg, "\t\t# (from %s)\n", mainopt->source);
+}
+
+/*
+ * print_option_list - print out options in effect from an
+ * array of options.
+ */
+static void
+print_option_list(struct option *opt, printer_func printer, void *arg)
+{
+ while (opt->name != NULL) {
+ if (opt->priority != OPRIO_DEFAULT
+ && opt->winner != (short int) -1)
+ print_option(opt + opt->winner, opt, printer, arg);
+ do {
+ ++opt;
+ } while (opt->flags & OPT_PRIOSUB);
+ }
+}
+
+/*
+ * print_options - print out what options are in effect.
+ */
+void
+print_options(printer_func printer, void *arg)
+{
+ struct option_list *list;
+ int i;
+
+ printer(arg, "pppd options in effect:\n");
+ print_option_list(general_options, printer, arg);
+ print_option_list(auth_options, printer, arg);
+ for (list = extra_options; list != NULL; list = list->next)
+ print_option_list(list->options, printer, arg);
+ print_option_list(the_channel->options, printer, arg);
+ for (i = 0; protocols[i] != NULL; ++i)
+ print_option_list(protocols[i]->options, printer, arg);
+}
+
+/*
+ * usage - print out a message telling how to use the program.
+ */
+static void
+usage(void)
+{
+ FILE *fp = stderr;
+ if (in_phase(PHASE_INITIALIZE)) {
+ fprintf(fp, "%s v%s\n", PACKAGE_NAME, PACKAGE_VERSION);
+ fprintf(fp, "Copyright (C) 1999-2022 Paul Mackerras, and others. All rights reserved.\n\n");
+
+
+ fprintf(fp, "License BSD: The 3 clause BSD license <https://opensource.org/licenses/BSD-3-Clause>\n");
+ fprintf(fp, "This is free software: you are free to change and redistribute it.\n");
+ fprintf(fp, "There is NO WARRANTY, to the extent permitted by law.\n\n");
+
+ fprintf(fp, "Report Bugs:\n %s\n\n", PACKAGE_BUGREPORT);
+ fprintf(fp, "Usage: %s [ options ], where options are:\n", progname);
+ fprintf(fp, " <device> Communicate over the named device\n");
+ fprintf(fp, " <speed> Set the baud rate to <speed>\n");
+ fprintf(fp, " <loc>:<rem> Set the local and/or remote interface IP\n");
+ fprintf(fp, " addresses. Either one may be omitted.\n");
+ fprintf(fp, " asyncmap <n> Set the desired async map to hex <n>\n");
+ fprintf(fp, " auth Require authentication from peer\n");
+ fprintf(fp, " connect <p> Invoke shell command <p> to set up the serial line\n");
+ fprintf(fp, " crtscts Use hardware RTS/CTS flow control\n");
+ fprintf(fp, " defaultroute Add default route through interface\n");
+ fprintf(fp, " file <f> Take options from file <f>\n");
+ fprintf(fp, " modem Use modem control lines\n");
+ fprintf(fp, " mru <n> Set MRU value to <n> for negotiation\n");
+ fprintf(fp, " show-options Display an extended list of options\n");
+ fprintf(fp, "See pppd(8) for more options.\n");
+ }
+}
+
+/*
+ * showhelp - print out usage message and exit.
+ */
+static int
+showhelp(char **argv)
+{
+ if (in_phase(PHASE_INITIALIZE)) {
+ usage();
+ exit(0);
+ }
+ return 0;
+}
+
+/*
+ * showversion - print out the version number and exit.
+ */
+static int
+showversion(char **argv)
+{
+ if (in_phase(PHASE_INITIALIZE)) {
+ fprintf(stdout, "pppd version %s\n", VERSION);
+ exit(0);
+ }
+ return 0;
+}
+
+/*
+ * Print a set of options including the name of the group of options
+ */
+static void
+showopts_list(FILE *fp, const char *title, struct option *list, ...)
+{
+ struct option *opt = list;
+ va_list varg;
+
+ if (opt && opt->name) {
+ va_start(varg, list);
+ vfprintf(fp, title, varg);
+ fprintf(fp, ":\n");
+ va_end(varg);
+
+ do {
+ fprintf(fp, " %-22s %s\n", opt->name, opt->description?:"");
+ opt++;
+ } while (opt && opt->name);
+
+ fprintf(fp, "\n");
+ }
+}
+
+/*
+ * Dumps the list of available options
+ */
+void
+showopts(void)
+{
+ struct option_list *list;
+ FILE *fp = stderr;
+ int i = 0;
+
+ showopts_list(fp, "General Options",
+ general_options);
+
+ showopts_list(fp, "Authentication Options",
+ auth_options);
+
+ for (list = extra_options; list != NULL; list = list->next)
+ showopts_list(fp, "Extra Options", list->options);
+
+ showopts_list(fp, "Channel Options",
+ the_channel->options);
+
+ for (i = 0; protocols[i] != NULL; ++i) {
+ if (protocols[i]->options != NULL) {
+ showopts_list(fp, "%s Options",
+ protocols[i]->options,
+ protocols[i]->name);
+ }
+ }
+}
+
+/*
+ * ppp_option_error - print a message about an error in an option.
+ * The message is logged, and also sent to
+ * stderr if in_phase(PHASE_INITIALIZE).
+ */
+void
+ppp_option_error(char *fmt, ...)
+{
+ va_list args;
+ char buf[1024];
+
+ va_start(args, fmt);
+ vslprintf(buf, sizeof(buf), fmt, args);
+ va_end(args);
+ if (in_phase(PHASE_INITIALIZE))
+ fprintf(stderr, "%s: %s\n", progname, buf);
+ syslog(LOG_ERR, "%s", buf);
+}
+
+#if 0
+/*
+ * readable - check if a file is readable by the real user.
+ */
+int
+readable(int fd)
+{
+ uid_t uid;
+ int i;
+ struct stat sbuf;
+
+ uid = getuid();
+ if (uid == 0)
+ return 1;
+ if (fstat(fd, &sbuf) != 0)
+ return 0;
+ if (sbuf.st_uid == uid)
+ return sbuf.st_mode & S_IRUSR;
+ if (sbuf.st_gid == getgid())
+ return sbuf.st_mode & S_IRGRP;
+ for (i = 0; i < ngroups; ++i)
+ if (sbuf.st_gid == groups[i])
+ return sbuf.st_mode & S_IRGRP;
+ return sbuf.st_mode & S_IROTH;
+}
+#endif
+
+/*
+ * Read a word from a file.
+ * Words are delimited by white-space or by quotes (" or ').
+ * Quotes, white-space and \ may be escaped with \.
+ * \<newline> is ignored.
+ */
+int
+getword(FILE *f, char *word, int *newlinep, char *filename)
+{
+ int c, len, escape;
+ int quoted, comment;
+ int value, digit, got, n;
+
+#define isoctal(c) ((c) >= '0' && (c) < '8')
+
+ *newlinep = 0;
+ len = 0;
+ escape = 0;
+ comment = 0;
+ quoted = 0;
+
+ /*
+ * First skip white-space and comments.
+ */
+ for (;;) {
+ c = getc(f);
+ if (c == EOF)
+ break;
+
+ /*
+ * A newline means the end of a comment; backslash-newline
+ * is ignored. Note that we cannot have escape && comment.
+ */
+ if (c == '\n') {
+ if (!escape) {
+ *newlinep = 1;
+ comment = 0;
+ } else
+ escape = 0;
+ continue;
+ }
+
+ /*
+ * Ignore characters other than newline in a comment.
+ */
+ if (comment)
+ continue;
+
+ /*
+ * If this character is escaped, we have a word start.
+ */
+ if (escape)
+ break;
+
+ /*
+ * If this is the escape character, look at the next character.
+ */
+ if (c == '\\') {