freebsd-nq/usr.bin/cpio/cmdline.c
Tim Kientzle 4b058a88d8 Custom command line parser for cpio; this is a little more
code but should be a lot fewer cross-platform compatibility
headaches.
2008-12-06 07:30:40 +00:00

342 lines
9.1 KiB
C

/*-
* Copyright (c) 2003-2007 Tim Kientzle
* 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
* in this position and unchanged.
* 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(S) ``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(S) 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 "cpio_platform.h"
__FBSDID("$FreeBSD$");
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_GRP_H
#include <grp.h>
#endif
#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include "cpio.h"
/*
* Short options for cpio. Please keep this sorted.
*/
static const char *short_options = "0AaBC:F:O:cdE:f:H:hijLlmopR:rtuvW:yZz";
/*
* Long options for cpio. Please keep this sorted.
*/
static const struct option {
const char *name;
int required; /* 1 if this option requires an argument */
int equivalent; /* Equivalent short option. */
} cpio_longopts[] = {
{ "create", 0, 'o' },
{ "extract", 0, 'i' },
{ "file", 1, 'F' },
{ "format", 1, 'H' },
{ "help", 0, 'h' },
{ "insecure", 0, OPTION_INSECURE },
{ "link", 0, 'l' },
{ "list", 0, 't' },
{ "make-directories", 0, 'd' },
{ "no-preserve-owner", 0, OPTION_NO_PRESERVE_OWNER },
{ "null", 0, '0' },
{ "owner", 1, 'R' },
{ "pass-through", 0, 'p' },
{ "preserve-modification-time", 0, 'm' },
{ "quiet", 0, OPTION_QUIET },
{ "unconditional", 0, 'u' },
{ "verbose", 0, 'v' },
{ "version", 0, OPTION_VERSION },
{ NULL, 0, 0 }
};
/*
* I used to try to select platform-provided getopt() or
* getopt_long(), but that caused a lot of headaches. In particular,
* I couldn't consistently use long options in the test harness
* because not all platforms have getopt_long(). That in turn led to
* overuse of the -W hack in the test harness, which made it rough to
* run the test harness against GNU cpio. (I periodically run the
* test harness here against GNU cpio as a sanity-check. Yes,
* I've found a couple of bugs in GNU cpio that way.)
*/
int
cpio_getopt(struct cpio *cpio)
{
enum { state_start = 0, state_next_word, state_short, state_long };
static int state = state_start;
static char *opt_word;
const struct option *popt, *match = NULL, *match2 = NULL;
const char *p, *long_prefix = "--";
size_t optlength;
int opt = '?';
int required = 0;
cpio->optarg = NULL;
/* First time through, initialize everything. */
if (state == state_start) {
/* Skip program name. */
++cpio->argv;
--cpio->argc;
state = state_next_word;
}
/*
* We're ready to look at the next word in argv.
*/
if (state == state_next_word) {
/* No more arguments, so no more options. */
if (cpio->argv[0] == NULL)
return (-1);
/* Doesn't start with '-', so no more options. */
if (cpio->argv[0][0] != '-')
return (-1);
/* "--" marks end of options; consume it and return. */
if (strcmp(cpio->argv[0], "--") == 0) {
++cpio->argv;
--cpio->argc;
return (-1);
}
/* Get next word for parsing. */
opt_word = *cpio->argv++;
--cpio->argc;
if (opt_word[1] == '-') {
/* Set up long option parser. */
state = state_long;
opt_word += 2; /* Skip leading '--' */
} else {
/* Set up short option parser. */
state = state_short;
++opt_word; /* Skip leading '-' */
}
}
/*
* We're parsing a group of POSIX-style single-character options.
*/
if (state == state_short) {
/* Peel next option off of a group of short options. */
opt = *opt_word++;
if (opt == '\0') {
/* End of this group; recurse to get next option. */
state = state_next_word;
return cpio_getopt(cpio);
}
/* Does this option take an argument? */
p = strchr(short_options, opt);
if (p == NULL)
return ('?');
if (p[1] == ':')
required = 1;
/* If it takes an argument, parse that. */
if (required) {
/* If arg is run-in, opt_word already points to it. */
if (opt_word[0] == '\0') {
/* Otherwise, pick up the next word. */
opt_word = *cpio->argv;
if (opt_word == NULL) {
cpio_warnc(0,
"Option -%c requires an argument",
opt);
return ('?');
}
++cpio->argv;
--cpio->argc;
}
if (opt == 'W') {
state = state_long;
long_prefix = "-W "; /* For clearer errors. */
} else {
state = state_next_word;
cpio->optarg = opt_word;
}
}
}
/* We're reading a long option, including -W long=arg convention. */
if (state == state_long) {
/* After this long option, we'll be starting a new word. */
state = state_next_word;
/* Option name ends at '=' if there is one. */
p = strchr(opt_word, '=');
if (p != NULL) {
optlength = (size_t)(p - opt_word);
cpio->optarg = (char *)(uintptr_t)(p + 1);
} else {
optlength = strlen(opt_word);
}
/* Search the table for an unambiguous match. */
for (popt = cpio_longopts; popt->name != NULL; popt++) {
/* Short-circuit if first chars don't match. */
if (popt->name[0] != opt_word[0])
continue;
/* If option is a prefix of name in table, record it.*/
if (strncmp(opt_word, popt->name, optlength) == 0) {
match2 = match; /* Record up to two matches. */
match = popt;
/* If it's an exact match, we're done. */
if (strlen(popt->name) == optlength) {
match2 = NULL; /* Forget the others. */
break;
}
}
}
/* Fail if there wasn't a unique match. */
if (match == NULL) {
cpio_warnc(0,
"Option %s%s is not supported",
long_prefix, opt_word);
return ('?');
}
if (match2 != NULL) {
cpio_warnc(0,
"Ambiguous option %s%s (matches --%s and --%s)",
long_prefix, opt_word, match->name, match2->name);
return ('?');
}
/* We've found a unique match; does it need an argument? */
if (match->required) {
/* Argument required: get next word if necessary. */
if (cpio->optarg == NULL) {
cpio->optarg = *cpio->argv;
if (cpio->optarg == NULL) {
cpio_warnc(0,
"Option %s%s requires an argument",
long_prefix, match->name);
return ('?');
}
++cpio->argv;
--cpio->argc;
}
} else {
/* Argument forbidden: fail if there is one. */
if (cpio->optarg != NULL) {
cpio_warnc(0,
"Option %s%s does not allow an argument",
long_prefix, match->name);
return ('?');
}
}
return (match->equivalent);
}
return (opt);
}
/*
* Parse the argument to the -R or --owner flag.
*
* The format is one of the following:
* <user> - Override user but not group
* <user>: - Override both, group is user's default group
* <user>:<group> - Override both
* :<group> - Override group but not user
*
* A period can be used instead of the colon.
*
* Sets uid/gid as appropriate, -1 indicates uid/gid not specified.
*
*/
int
owner_parse(const char *spec, int *uid, int *gid)
{
const char *u, *ue, *g;
*uid = -1;
*gid = -1;
/*
* Split spec into [user][:.][group]
* u -> first char of username, NULL if no username
* ue -> first char after username (colon, period, or \0)
* g -> first char of group name
*/
if (*spec == ':' || *spec == '.') {
/* If spec starts with ':' or '.', then just group. */
ue = u = NULL;
g = spec + 1;
} else {
/* Otherwise, [user] or [user][:] or [user][:][group] */
ue = u = spec;
while (*ue != ':' && *ue != '.' && *ue != '\0')
++ue;
g = ue;
if (*g != '\0') /* Skip : or . to find first char of group. */
++g;
}
if (u != NULL) {
/* Look up user: ue is first char after end of user. */
char *user;
struct passwd *pwent;
user = (char *)malloc(ue - u + 1);
if (user == NULL) {
cpio_warnc(errno, "Couldn't allocate memory");
return (1);
}
memcpy(user, u, ue - u);
user[ue - u] = '\0';
pwent = getpwnam(user);
if (pwent == NULL) {
cpio_warnc(errno, "Couldn't lookup user ``%s''", user);
return (1);
}
free(user);
*uid = pwent->pw_uid;
if (*ue != '\0' && *g == '\0')
*gid = pwent->pw_gid;
}
if (*g != '\0') {
struct group *grp;
grp = getgrnam(g);
if (grp != NULL)
*gid = grp->gr_gid;
else {
cpio_warnc(errno, "Couldn't look up group ``%s''", g);
return (1);
}
}
return (0);
}