freebsd-dev/lib/libarchive/archive_string.c

378 lines
9.3 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.
* 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 "archive_platform.h"
__FBSDID("$FreeBSD$");
/*
* Basic resizable string support, to simplify manipulating arbitrary-sized
* strings while minimizing heap activity.
*/
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_WCHAR_H
#include <wchar.h>
#endif
#include "archive_private.h"
#include "archive_string.h"
struct archive_string *
__archive_string_append(struct archive_string *as, const char *p, size_t s)
{
if (__archive_string_ensure(as, as->length + s + 1) == NULL)
__archive_errx(1, "Out of memory");
memcpy(as->s + as->length, p, s);
as->s[as->length + s] = 0;
as->length += s;
return (as);
}
void
__archive_string_copy(struct archive_string *dest, struct archive_string *src)
{
if (src->length == 0)
dest->length = 0;
else {
if (__archive_string_ensure(dest, src->length + 1) == NULL)
__archive_errx(1, "Out of memory");
memcpy(dest->s, src->s, src->length);
dest->length = src->length;
dest->s[dest->length] = 0;
}
}
void
__archive_string_concat(struct archive_string *dest, struct archive_string *src)
{
if (src->length > 0) {
if (__archive_string_ensure(dest, dest->length + src->length + 1) == NULL)
__archive_errx(1, "Out of memory");
memcpy(dest->s + dest->length, src->s, src->length);
dest->length += src->length;
dest->s[dest->length] = 0;
}
}
void
__archive_string_free(struct archive_string *as)
{
as->length = 0;
as->buffer_length = 0;
if (as->s != NULL) {
free(as->s);
as->s = NULL;
}
}
/* Returns NULL on any allocation failure. */
struct archive_string *
__archive_string_ensure(struct archive_string *as, size_t s)
{
/* If buffer is already big enough, don't reallocate. */
if (as->s && (s <= as->buffer_length))
return (as);
/*
* Growing the buffer at least exponentially ensures that
* append operations are always linear in the number of
* characters appended. Using a smaller growth rate for
* larger buffers reduces memory waste somewhat at the cost of
* a larger constant factor.
*/
if (as->buffer_length < 32)
/* Start with a minimum 32-character buffer. */
as->buffer_length = 32;
else if (as->buffer_length < 8192)
/* Buffers under 8k are doubled for speed. */
as->buffer_length *= 2;
else {
/* Buffers 8k and over grow by at least 25% each time. */
size_t old_length = as->buffer_length;
as->buffer_length = (as->buffer_length * 5) / 4;
/* Be safe: If size wraps, release buffer and return NULL. */
if (as->buffer_length < old_length) {
free(as->s);
as->s = NULL;
return (NULL);
}
}
/*
* The computation above is a lower limit to how much we'll
* grow the buffer. In any case, we have to grow it enough to
* hold the request.
*/
if (as->buffer_length < s)
as->buffer_length = s;
/* Now we can reallocate the buffer. */
as->s = (char *)realloc(as->s, as->buffer_length);
if (as->s == NULL)
return (NULL);
return (as);
}
struct archive_string *
__archive_strncat(struct archive_string *as, const char *p, size_t n)
{
size_t s;
const char *pp;
/* Like strlen(p), except won't examine positions beyond p[n]. */
s = 0;
pp = p;
while (*pp && s < n) {
pp++;
s++;
}
return (__archive_string_append(as, p, s));
}
struct archive_string *
__archive_strappend_char(struct archive_string *as, char c)
{
return (__archive_string_append(as, &c, 1));
}
struct archive_string *
__archive_strappend_int(struct archive_string *as, int d, int base)
{
static const char *digits = "0123456789abcdef";
if (d < 0) {
__archive_strappend_char(as, '-');
d = -d;
}
if (d >= base)
__archive_strappend_int(as, d/base, base);
__archive_strappend_char(as, digits[d % base]);
return (as);
}
/*
* Home-grown wctomb for UTF-8.
*/
static int
my_wctomb_utf8(char *p, wchar_t wc)
{
if (p == NULL)
/* UTF-8 doesn't use shift states. */
return (0);
if (wc <= 0x7f) {
p[0] = (char)wc;
return (1);
}
if (wc <= 0x7ff) {
p[0] = 0xc0 | ((wc >> 6) & 0x1f);
p[1] = 0x80 | (wc & 0x3f);
return (2);
}
if (wc <= 0xffff) {
p[0] = 0xe0 | ((wc >> 12) & 0x0f);
p[1] = 0x80 | ((wc >> 6) & 0x3f);
p[2] = 0x80 | (wc & 0x3f);
return (3);
}
if (wc <= 0x1fffff) {
p[0] = 0xf0 | ((wc >> 18) & 0x07);
p[1] = 0x80 | ((wc >> 12) & 0x3f);
p[2] = 0x80 | ((wc >> 6) & 0x3f);
p[3] = 0x80 | (wc & 0x3f);
return (4);
}
/* Unicode has no codes larger than 0x1fffff. */
/*
* Awkward point: UTF-8 <-> wchar_t conversions
* can actually fail.
*/
return (-1);
}
static int
my_wcstombs(struct archive_string *as, const wchar_t *w,
int (*func)(char *, wchar_t))
{
int n;
char *p;
char buff[256];
/* Clear the shift state before starting. */
(*func)(NULL, L'\0');
/*
* Convert one wide char at a time into 'buff', whenever that
* fills, append it to the string.
*/
p = buff;
while (*w != L'\0') {
/* Flush the buffer when we have <=16 bytes free. */
/* (No encoding has a single character >16 bytes.) */
if ((size_t)(p - buff) >= (size_t)(sizeof(buff) - 16)) {
*p = '\0';
archive_strcat(as, buff);
p = buff;
}
n = (*func)(p, *w++);
if (n == -1)
return (-1);
p += n;
}
*p = '\0';
archive_strcat(as, buff);
return (0);
}
/*
* Translates a wide character string into UTF-8 and appends
* to the archive_string. Note: returns NULL if conversion fails.
*/
struct archive_string *
__archive_strappend_w_utf8(struct archive_string *as, const wchar_t *w)
{
if (my_wcstombs(as, w, my_wctomb_utf8))
return (NULL);
return (as);
}
/*
* Translates a wide character string into current locale character set
* and appends to the archive_string. Note: returns NULL if conversion
* fails.
*/
struct archive_string *
__archive_strappend_w_mbs(struct archive_string *as, const wchar_t *w)
{
#if HAVE_WCTOMB
if (my_wcstombs(as, w, wctomb))
return (NULL);
#else
/* TODO: Can we do better than this? Are there platforms
* that have locale support but don't have wctomb()? */
if (my_wcstombs(as, w, my_wctomb_utf8))
return (NULL);
#endif
return (as);
}
/*
* Home-grown mbtowc for UTF-8. Some systems lack UTF-8
* (or even lack mbtowc()) and we need UTF-8 support for pax
* format. So please don't replace this with a call to the
* standard mbtowc() function!
*/
static int
my_mbtowc_utf8(wchar_t *pwc, const char *s, size_t n)
{
int ch;
/* Standard behavior: a NULL value for 's' just resets shift state. */
if (s == NULL)
return (0);
/* If length argument is zero, don't look at the first character. */
if (n <= 0)
return (-1);
/*
* Decode 1-4 bytes depending on the value of the first byte.
*/
ch = (unsigned char)*s;
if (ch == 0) {
return (0); /* Standard: return 0 for end-of-string. */
}
if ((ch & 0x80) == 0) {
*pwc = ch & 0x7f;
return (1);
}
if ((ch & 0xe0) == 0xc0) {
if (n < 2)
return (-1);
if ((s[1] & 0xc0) != 0x80) return (-1);
*pwc = ((ch & 0x1f) << 6) | (s[1] & 0x3f);
return (2);
}
if ((ch & 0xf0) == 0xe0) {
if (n < 3)
return (-1);
if ((s[1] & 0xc0) != 0x80) return (-1);
if ((s[2] & 0xc0) != 0x80) return (-1);
*pwc = ((ch & 0x0f) << 12)
| ((s[1] & 0x3f) << 6)
| (s[2] & 0x3f);
return (3);
}
if ((ch & 0xf8) == 0xf0) {
if (n < 4)
return (-1);
if ((s[1] & 0xc0) != 0x80) return (-1);
if ((s[2] & 0xc0) != 0x80) return (-1);
if ((s[3] & 0xc0) != 0x80) return (-1);
*pwc = ((ch & 0x07) << 18)
| ((s[1] & 0x3f) << 12)
| ((s[2] & 0x3f) << 6)
| (s[3] & 0x3f);
return (4);
}
/* Invalid first byte. */
return (-1);
}
/*
* Return a wide-character string by converting this archive_string
* from UTF-8.
*/
wchar_t *
__archive_string_utf8_w(struct archive_string *as)
{
wchar_t *ws, *dest;
const char *src;
int n;
int err;
ws = (wchar_t *)malloc((as->length + 1) * sizeof(wchar_t));
if (ws == NULL)
__archive_errx(1, "Out of memory");
err = 0;
dest = ws;
src = as->s;
while (*src != '\0') {
n = my_mbtowc_utf8(dest, src, 8);
if (n == 0)
break;
if (n < 0) {
free(ws);
return (NULL);
}
dest++;
src += n;
}
*dest++ = L'\0';
return (ws);
}