freebsd-dev/stand/common/commands.c
Mitchell Horne 8859960436 loader: always install help files
Address two issues with current help file logic:

The existing condition prevents the common help file from being
installed when there are no additional help files defined. This results
in no loader.help on EFI platforms, for example.

Second, due to the fact that we build and install multiple loader types,
each successive install will clobber the previous loader.help. The
result is that we could lose type-specific commands, or possibly list
them in loaders that do not have such commands.

Instead, give each loader type a uniquely named help file. The EFI
loader will look for /boot/loader.help.efi, userboot will look for
/boot/loader.help.userboot, etc. The interpreter variant has no effect
on which help file is loaded.

This leaves the old /boot/loader.help unused.

Some credit for the final approach goes to Mathieu <sigsys@gmail.com>
for their version of the fix in https://reviews.freebsd.org/D22951.

PR:		267134
Reported by:	Daniel O'Connor <darius@dons.net.au>
Reviewed by:	imp
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D28591
2023-02-03 16:35:06 -04:00

588 lines
12 KiB
C

/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <stand.h>
#include <string.h>
#include "bootstrap.h"
const char *command_errmsg;
/* XXX should have procedural interface for setting, size limit? */
char command_errbuf[COMMAND_ERRBUFSZ];
static int page_file(char *filename);
/*
* Help is read from a formatted text file.
*
* Entries in the file are formatted as
# Ttopic [Ssubtopic] Ddescription
help
text
here
#
*
* Note that for code simplicity's sake, the above format must be followed
* exactly.
*
* Subtopic entries must immediately follow the topic (this is used to
* produce the listing of subtopics).
*
* If no argument(s) are supplied by the user, the help for 'help' is displayed.
*/
COMMAND_SET(help, "help", "detailed help", command_help);
static int
help_getnext(int fd, char **topic, char **subtopic, char **desc)
{
char line[81], *cp, *ep;
/* Make sure we provide sane values. */
*topic = *subtopic = *desc = NULL;
for (;;) {
if (fgetstr(line, 80, fd) < 0)
return (0);
if (strlen(line) < 3 || line[0] != '#' || line[1] != ' ')
continue;
cp = line + 2;
while (cp != NULL && *cp != 0) {
ep = strchr(cp, ' ');
if (*cp == 'T' && *topic == NULL) {
if (ep != NULL)
*ep++ = 0;
*topic = strdup(cp + 1);
} else if (*cp == 'S' && *subtopic == NULL) {
if (ep != NULL)
*ep++ = 0;
*subtopic = strdup(cp + 1);
} else if (*cp == 'D') {
*desc = strdup(cp + 1);
ep = NULL;
}
cp = ep;
}
if (*topic == NULL) {
free(*subtopic);
free(*desc);
*subtopic = *desc = NULL;
continue;
}
return (1);
}
}
static int
help_emitsummary(char *topic, char *subtopic, char *desc)
{
int i;
pager_output(" ");
pager_output(topic);
i = strlen(topic);
if (subtopic != NULL) {
pager_output(" ");
pager_output(subtopic);
i += strlen(subtopic) + 1;
}
if (desc != NULL) {
do {
pager_output(" ");
} while (i++ < 30);
pager_output(desc);
}
return (pager_output("\n"));
}
static int
command_help(int argc, char *argv[])
{
char buf[81]; /* XXX buffer size? */
int hfd, matched, doindex;
char *topic, *subtopic, *t, *s, *d;
/* page the help text from our load path */
snprintf(buf, sizeof(buf), "%s/boot/%s", getenv("loaddev"),
HELP_FILENAME);
if ((hfd = open(buf, O_RDONLY)) < 0) {
printf("Verbose help not available, "
"use '?' to list commands\n");
return (CMD_OK);
}
/* pick up request from arguments */
topic = subtopic = NULL;
switch (argc) {
case 3:
subtopic = strdup(argv[2]);
/* FALLTHROUGH */
case 2:
topic = strdup(argv[1]);
break;
case 1:
topic = strdup("help");
break;
default:
command_errmsg = "usage is 'help <topic> [<subtopic>]";
close(hfd);
return(CMD_ERROR);
}
/* magic "index" keyword */
doindex = strcmp(topic, "index") == 0? 1 : 0;
matched = doindex;
/* Scan the helpfile looking for help matching the request */
pager_open();
while (help_getnext(hfd, &t, &s, &d)) {
if (doindex) { /* dink around formatting */
if (help_emitsummary(t, s, d))
break;
} else if (strcmp(topic, t)) {
/* topic mismatch */
if (matched) {
/* nothing more on this topic, stop scanning */
break;
}
} else {
/* topic matched */
matched = 1;
if ((subtopic == NULL && s == NULL) ||
(subtopic != NULL && s != NULL &&
strcmp(subtopic, s) == 0)) {
/* exact match, print text */
while (fgetstr(buf, 80, hfd) >= 0 &&
buf[0] != '#') {
if (pager_output(buf))
break;
if (pager_output("\n"))
break;
}
} else if (subtopic == NULL && s != NULL) {
/* topic match, list subtopics */
if (help_emitsummary(t, s, d))
break;
}
}
free(t);
free(s);
free(d);
t = s = d = NULL;
}
free(t);
free(s);
free(d);
pager_close();
close(hfd);
if (!matched) {
snprintf(command_errbuf, sizeof(command_errbuf),
"no help available for '%s'", topic);
free(topic);
free(subtopic);
return (CMD_ERROR);
}
free(topic);
free(subtopic);
return (CMD_OK);
}
COMMAND_SET(commandlist, "?", "list commands", command_commandlist);
/*
* Please note: although we use the pager for the list of commands,
* this routine is called from the ? FORTH function which then
* unconditionally prints some commands. This will lead to anomalous
* behavior. There's no 'pager_output' binding to FORTH to allow
* things to work right, so I'm documenting the bug rather than
* fixing it.
*/
static int
command_commandlist(int argc __unused, char *argv[] __unused)
{
struct bootblk_command **cmdp;
int res;
char name[20];
res = 0;
pager_open();
res = pager_output("Available commands:\n");
SET_FOREACH(cmdp, Xcommand_set) {
if (res)
break;
if ((*cmdp)->c_name != NULL && (*cmdp)->c_desc != NULL) {
snprintf(name, sizeof(name), " %-15s ",
(*cmdp)->c_name);
pager_output(name);
pager_output((*cmdp)->c_desc);
res = pager_output("\n");
}
}
pager_close();
return (CMD_OK);
}
/*
* XXX set/show should become set/echo if we have variable
* substitution happening.
*/
COMMAND_SET(show, "show", "show variable(s)", command_show);
static int
command_show(int argc, char *argv[])
{
struct env_var *ev;
char *cp;
if (argc < 2) {
/*
* With no arguments, print everything.
*/
pager_open();
for (ev = environ; ev != NULL; ev = ev->ev_next) {
pager_output(ev->ev_name);
cp = getenv(ev->ev_name);
if (cp != NULL) {
pager_output("=");
pager_output(cp);
}
if (pager_output("\n"))
break;
}
pager_close();
} else {
if ((cp = getenv(argv[1])) != NULL) {
printf("%s\n", cp);
} else {
snprintf(command_errbuf, sizeof(command_errbuf),
"variable '%s' not found", argv[1]);
return (CMD_ERROR);
}
}
return (CMD_OK);
}
COMMAND_SET(set, "set", "set a variable", command_set);
static int
command_set(int argc, char *argv[])
{
int err;
if (argc != 2) {
command_errmsg = "wrong number of arguments";
return (CMD_ERROR);
} else {
#ifdef LOADER_VERIEXEC
/*
* Impose restrictions if input is not verified
*/
const char *restricted[] = {
"boot",
"init",
"loader.ve.",
"rootfs",
"secur",
"vfs.",
NULL,
};
const char **cp;
int ves;
ves = ve_status_get(-1);
if (ves == VE_UNVERIFIED_OK) {
#ifdef LOADER_VERIEXEC_TESTING
printf("Checking: %s\n", argv[1]);
#endif
for (cp = restricted; *cp; cp++) {
if (strncmp(argv[1], *cp, strlen(*cp)) == 0) {
printf("Ignoring restricted variable: %s\n",
argv[1]);
return (CMD_OK);
}
}
}
#endif
if ((err = putenv(argv[1])) != 0) {
command_errmsg = strerror(err);
return (CMD_ERROR);
}
}
return (CMD_OK);
}
COMMAND_SET(unset, "unset", "unset a variable", command_unset);
static int
command_unset(int argc, char *argv[])
{
int err;
if (argc != 2) {
command_errmsg = "wrong number of arguments";
return (CMD_ERROR);
} else {
if ((err = unsetenv(argv[1])) != 0) {
command_errmsg = strerror(err);
return (CMD_ERROR);
}
}
return (CMD_OK);
}
COMMAND_SET(echo, "echo", "echo arguments", command_echo);
static int
command_echo(int argc, char *argv[])
{
char *s;
int nl, ch;
nl = 0;
optind = 1;
optreset = 1;
while ((ch = getopt(argc, argv, "n")) != -1) {
switch (ch) {
case 'n':
nl = 1;
break;
case '?':
default:
/* getopt has already reported an error */
return (CMD_OK);
}
}
argv += (optind);
argc -= (optind);
s = unargv(argc, argv);
if (s != NULL) {
printf("%s", s);
free(s);
}
if (!nl)
printf("\n");
return (CMD_OK);
}
/*
* A passable emulation of the sh(1) command of the same name.
*/
COMMAND_SET(read, "read", "read input from the terminal", command_read);
static int
command_read(int argc, char *argv[])
{
char *prompt;
int timeout;
time_t when;
char *cp;
char *name;
char buf[256]; /* XXX size? */
int c;
timeout = -1;
prompt = NULL;
optind = 1;
optreset = 1;
while ((c = getopt(argc, argv, "p:t:")) != -1) {
switch (c) {
case 'p':
prompt = optarg;
break;
case 't':
timeout = strtol(optarg, &cp, 0);
if (cp == optarg) {
snprintf(command_errbuf,
sizeof(command_errbuf),
"bad timeout '%s'", optarg);
return (CMD_ERROR);
}
break;
default:
return (CMD_OK);
}
}
argv += (optind);
argc -= (optind);
name = (argc > 0) ? argv[0]: NULL;
if (prompt != NULL)
printf("%s", prompt);
if (timeout >= 0) {
when = time(NULL) + timeout;
while (!ischar())
if (time(NULL) >= when)
return (CMD_OK); /* is timeout an error? */
}
ngets(buf, sizeof(buf));
if (name != NULL)
setenv(name, buf, 1);
return (CMD_OK);
}
/*
* File pager
*/
COMMAND_SET(more, "more", "show contents of a file", command_more);
static int
command_more(int argc, char *argv[])
{
int i;
int res;
char line[80];
res = 0;
pager_open();
for (i = 1; (i < argc) && (res == 0); i++) {
snprintf(line, sizeof(line), "*** FILE %s BEGIN ***\n",
argv[i]);
if (pager_output(line))
break;
res = page_file(argv[i]);
if (!res) {
snprintf(line, sizeof(line), "*** FILE %s END ***\n",
argv[i]);
res = pager_output(line);
}
}
pager_close();
return (CMD_OK);
}
static int
page_file(char *filename)
{
int result;
result = pager_file(filename);
if (result == -1) {
snprintf(command_errbuf, sizeof(command_errbuf),
"error showing %s", filename);
}
return (result);
}
/*
* List all disk-like devices
*/
COMMAND_SET(lsdev, "lsdev", "list all devices", command_lsdev);
static int
command_lsdev(int argc, char *argv[])
{
int verbose, ch, i;
char line[80];
verbose = 0;
optind = 1;
optreset = 1;
while ((ch = getopt(argc, argv, "v")) != -1) {
switch (ch) {
case 'v':
verbose = 1;
break;
case '?':
default:
/* getopt has already reported an error */
return (CMD_OK);
}
}
argv += (optind);
argc -= (optind);
pager_open();
for (i = 0; devsw[i] != NULL; i++) {
if (devsw[i]->dv_print != NULL) {
if (devsw[i]->dv_print(verbose))
break;
} else {
snprintf(line, sizeof(line), "%s: (unknown)\n",
devsw[i]->dv_name);
if (pager_output(line))
break;
}
}
pager_close();
return (CMD_OK);
}
static int
command_readtest(int argc, char *argv[])
{
int fd;
time_t start, end;
char buf[512];
ssize_t rv, count = 0;
if (argc != 2) {
snprintf(command_errbuf, sizeof(command_errbuf),
"Usage: readtest <filename>");
return (CMD_ERROR);
}
start = getsecs();
if ((fd = open(argv[1], O_RDONLY)) < 0) {
snprintf(command_errbuf, sizeof(command_errbuf),
"can't open '%s'", argv[1]);
return (CMD_ERROR);
}
while ((rv = read(fd, buf, sizeof(buf))) > 0)
count += rv;
end = getsecs();
printf("Received %zd bytes during %jd seconds\n", count, (intmax_t)end - start);
close(fd);
return (CMD_OK);
}
COMMAND_SET(readtest, "readtest", "Time a file read", command_readtest);
static int
command_quit(int argc, char *argv[])
{
exit(0);
return (CMD_OK);
}
COMMAND_SET(quit, "quit", "exit the loader", command_quit);