freebsd-dev/usr.bin/tar/subst.c
2010-04-11 16:27:38 +00:00

290 lines
6.7 KiB
C

/*-
* Copyright (c) 2008 Joerg Sonnenberger
* 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(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 "bsdtar_platform.h"
__FBSDID("$FreeBSD$");
#if HAVE_REGEX_H
#include "bsdtar.h"
#include <errno.h>
#include <regex.h>
#include <stdlib.h>
#include <string.h>
#ifndef REG_BASIC
#define REG_BASIC 0
#endif
#include "err.h"
struct subst_rule {
struct subst_rule *next;
regex_t re;
char *result;
unsigned int global:1, print:1, symlink:1;
};
struct substitution {
struct subst_rule *first_rule, *last_rule;
};
static void
init_substitution(struct bsdtar *bsdtar)
{
struct substitution *subst;
bsdtar->substitution = subst = malloc(sizeof(*subst));
if (subst == NULL)
bsdtar_errc(1, errno, "Out of memory");
subst->first_rule = subst->last_rule = NULL;
}
void
add_substitution(struct bsdtar *bsdtar, const char *rule_text)
{
struct subst_rule *rule;
struct substitution *subst;
const char *end_pattern, *start_subst;
char *pattern;
int r;
if ((subst = bsdtar->substitution) == NULL) {
init_substitution(bsdtar);
subst = bsdtar->substitution;
}
rule = malloc(sizeof(*rule));
if (rule == NULL)
bsdtar_errc(1, errno, "Out of memory");
rule->next = NULL;
if (subst->last_rule == NULL)
subst->first_rule = rule;
else
subst->last_rule->next = rule;
subst->last_rule = rule;
if (*rule_text == '\0')
bsdtar_errc(1, 0, "Empty replacement string");
end_pattern = strchr(rule_text + 1, *rule_text);
if (end_pattern == NULL)
bsdtar_errc(1, 0, "Invalid replacement string");
pattern = malloc(end_pattern - rule_text);
if (pattern == NULL)
bsdtar_errc(1, errno, "Out of memory");
memcpy(pattern, rule_text + 1, end_pattern - rule_text - 1);
pattern[end_pattern - rule_text - 1] = '\0';
if ((r = regcomp(&rule->re, pattern, REG_BASIC)) != 0) {
char buf[80];
regerror(r, &rule->re, buf, sizeof(buf));
bsdtar_errc(1, 0, "Invalid regular expression: %s", buf);
}
free(pattern);
start_subst = end_pattern + 1;
end_pattern = strchr(start_subst, *rule_text);
if (end_pattern == NULL)
bsdtar_errc(1, 0, "Invalid replacement string");
rule->result = malloc(end_pattern - start_subst + 1);
if (rule->result == NULL)
bsdtar_errc(1, errno, "Out of memory");
memcpy(rule->result, start_subst, end_pattern - start_subst);
rule->result[end_pattern - start_subst] = '\0';
rule->global = 0;
rule->print = 0;
rule->symlink = 0;
while (*++end_pattern) {
switch (*end_pattern) {
case 'g':
case 'G':
rule->global = 1;
break;
case 'p':
case 'P':
rule->print = 1;
break;
case 's':
case 'S':
rule->symlink = 1;
break;
default:
bsdtar_errc(1, 0, "Invalid replacement flag %c", *end_pattern);
}
}
}
static void
realloc_strncat(char **str, const char *append, size_t len)
{
char *new_str;
size_t old_len;
if (*str == NULL)
old_len = 0;
else
old_len = strlen(*str);
new_str = malloc(old_len + len + 1);
if (new_str == NULL)
bsdtar_errc(1, errno, "Out of memory");
memcpy(new_str, *str, old_len);
memcpy(new_str + old_len, append, len);
new_str[old_len + len] = '\0';
free(*str);
*str = new_str;
}
static void
realloc_strcat(char **str, const char *append)
{
char *new_str;
size_t old_len;
if (*str == NULL)
old_len = 0;
else
old_len = strlen(*str);
new_str = malloc(old_len + strlen(append) + 1);
if (new_str == NULL)
bsdtar_errc(1, errno, "Out of memory");
memcpy(new_str, *str, old_len);
strcpy(new_str + old_len, append);
free(*str);
*str = new_str;
}
int
apply_substitution(struct bsdtar *bsdtar, const char *name, char **result, int symlink_only)
{
const char *path = name;
regmatch_t matches[10];
size_t i, j;
struct subst_rule *rule;
struct substitution *subst;
int c, got_match, print_match;
*result = NULL;
if ((subst = bsdtar->substitution) == NULL)
return 0;
got_match = 0;
print_match = 0;
for (rule = subst->first_rule; rule != NULL; rule = rule->next) {
if (symlink_only && !rule->symlink)
continue;
if (regexec(&rule->re, name, 10, matches, 0))
continue;
got_match = 1;
print_match |= rule->print;
realloc_strncat(result, name, matches[0].rm_so);
for (i = 0, j = 0; rule->result[i] != '\0'; ++i) {
if (rule->result[i] == '~') {
realloc_strncat(result, rule->result + j, i - j);
realloc_strncat(result, name, matches[0].rm_eo);
j = i + 1;
continue;
}
if (rule->result[i] != '\\')
continue;
++i;
c = rule->result[i];
switch (c) {
case '~':
case '\\':
realloc_strncat(result, rule->result + j, i - j - 1);
j = i;
break;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
realloc_strncat(result, rule->result + j, i - j - 1);
if ((size_t)(c - '0') > (size_t)(rule->re.re_nsub)) {
free(*result);
*result = NULL;
return -1;
}
realloc_strncat(result, name + matches[c - '0'].rm_so, matches[c - '0'].rm_eo - matches[c - '0'].rm_so);
j = i + 1;
break;
default:
/* Just continue; */
break;
}
}
realloc_strcat(result, rule->result + j);
name += matches[0].rm_eo;
if (!rule->global)
break;
}
if (got_match)
realloc_strcat(result, name);
if (print_match)
fprintf(stderr, "%s >> %s\n", path, *result);
return got_match;
}
void
cleanup_substitution(struct bsdtar *bsdtar)
{
struct subst_rule *rule;
struct substitution *subst;
if ((subst = bsdtar->substitution) == NULL)
return;
while ((rule = subst->first_rule) != NULL) {
subst->first_rule = rule->next;
free(rule->result);
free(rule);
}
free(subst);
}
#endif /* HAVE_REGEX_H */