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mpv/misc/charset_conv.c
wm4 8a9b64329c Relicense some non-MPlayer source files to LGPL 2.1 or later
This covers source files which were added in mplayer2 and mpv times
only, and where all code is covered by LGPL relicensing agreements.

There are probably more files to which this applies, but I'm being
conservative here.

A file named ao_sdl.c exists in MPlayer too, but the mpv one is a
complete rewrite, and was added some time after the original ao_sdl.c
was removed. The same applies to vo_sdl.c, for which the SDL2 API is
radically different in addition (MPlayer supports SDL 1.2 only).

common.c contains only code written by me. But common.h is a strange
case: although it originally was named mp_common.h and exists in MPlayer
too, by now it contains only definitions written by uau and me. The
exceptions are the CONTROL_ defines - thus not changing the license of
common.h yet.

codec_tags.c contained once large tables generated from MPlayer's
codecs.conf, but all of these tables were removed.

From demux_playlist.c I'm removing a code fragment from someone who was
not asked; this probably could be done later (see commit 15dccc37).

misc.c is a bit complicated to reason about (it was split off mplayer.c
and thus contains random functions out of this file), but actually all
functions have been added post-MPlayer. Except get_relative_time(),
which was written by uau, but looks similar to 3 different versions of
something similar in each of the Unix/win32/OSX timer source files. I'm
not sure what that means in regards to copyright, so I've just moved it
into another still-GPL source file for now.

screenshot.c once had some minor parts of MPlayer's vf_screenshot.c, but
they're all gone.
2016-01-19 18:36:06 +01:00

355 lines
11 KiB
C

/*
* This file is part of mpv.
*
* Based on code taken from libass (ISC license), which was originally part
* of MPlayer (GPL).
* Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <errno.h>
#include <strings.h>
#include <assert.h>
#include "config.h"
#include "common/msg.h"
#if HAVE_ENCA
#include <enca.h>
#endif
#if HAVE_LIBGUESS
#include <libguess.h>
#endif
#if HAVE_UCHARDET
#include <uchardet.h>
#endif
#if HAVE_ICONV
#include <iconv.h>
#endif
#include "charset_conv.h"
bool mp_charset_is_utf8(const char *user_cp)
{
return user_cp && (strcasecmp(user_cp, "utf8") == 0 ||
strcasecmp(user_cp, "utf-8") == 0);
}
bool mp_charset_is_utf16(const char *user_cp)
{
bstr s = bstr0(user_cp);
return bstr_case_startswith(s, bstr0("utf16")) ||
bstr_case_startswith(s, bstr0("utf-16"));
}
// Split the string on ':' into components.
// out_arr is at least max entries long.
// Return number of out_arr entries filled.
static int split_colon(const char *user_cp, int max, bstr *out_arr)
{
if (!user_cp || max < 1)
return 0;
int count = 0;
while (1) {
const char *next = strchr(user_cp, ':');
if (next && max - count > 1) {
out_arr[count++] = (bstr){(char *)user_cp, next - user_cp};
user_cp = next + 1;
} else {
out_arr[count++] = (bstr){(char *)user_cp, strlen(user_cp)};
break;
}
}
return count;
}
// Returns true if user_cp implies that calling mp_charset_guess() on the
// input data is required to determine the real codepage. This is the case
// if user_cp is not a real iconv codepage, but a magic value that requests
// for example ENCA charset auto-detection.
bool mp_charset_requires_guess(const char *user_cp)
{
bstr res[2] = {{0}};
int r = split_colon(user_cp, 2, res);
// Note that "utf8" is the UTF-8 codepage, while "utf8:..." specifies UTF-8
// by default, plus a codepage that is used if the input is not UTF-8.
return bstrcasecmp0(res[0], "enca") == 0 ||
bstrcasecmp0(res[0], "uchardet") == 0 ||
bstrcasecmp0(res[0], "auto") == 0 ||
bstrcasecmp0(res[0], "guess") == 0 ||
(r > 1 && bstrcasecmp0(res[0], "utf-8") == 0) ||
(r > 1 && bstrcasecmp0(res[0], "utf8") == 0);
}
static const char *const utf_bom[3] = {"\xEF\xBB\xBF", "\xFF\xFE", "\xFE\xFF"};
static const char *const utf_enc[3] = {"utf-8", "utf-16le", "utf-16be"};
static const char *ms_bom_guess(bstr buf)
{
for (int n = 0; n < 3; n++) {
if (bstr_startswith0(buf, utf_bom[n]))
return utf_enc[n];
}
return NULL;
}
#if HAVE_ENCA
static const char *enca_guess(struct mp_log *log, bstr buf, const char *language)
{
// Do our own UTF-8 detection, because ENCA seems to get it wrong sometimes
// (suggested by divVerent). Explicitly allow cut-off UTF-8.
if (bstr_validate_utf8(buf) > -8)
return "UTF-8";
if (!language || !language[0])
language = "__"; // neutral language
const char *detected_cp = NULL;
EncaAnalyser analyser = enca_analyser_alloc(language);
if (analyser) {
enca_set_termination_strictness(analyser, 0);
EncaEncoding enc = enca_analyse_const(analyser, buf.start, buf.len);
const char *tmp = enca_charset_name(enc.charset, ENCA_NAME_STYLE_ICONV);
if (tmp && enc.charset != ENCA_CS_UNKNOWN)
detected_cp = tmp;
enca_analyser_free(analyser);
} else {
mp_err(log, "ENCA doesn't know language '%s'\n", language);
size_t langcnt;
const char **languages = enca_get_languages(&langcnt);
mp_err(log, "ENCA supported languages:");
for (int i = 0; i < langcnt; i++)
mp_err(log, " %s", languages[i]);
mp_err(log, "\n");
free(languages);
}
return detected_cp;
}
#endif
#if HAVE_LIBGUESS
static const char *libguess_guess(struct mp_log *log, bstr buf,
const char *language)
{
if (!language || !language[0] || strcmp(language, "help") == 0) {
mp_err(log, "libguess needs a language: "
"japanese taiwanese chinese korean russian arabic turkish "
"greek hebrew polish baltic\n");
return NULL;
}
return libguess_determine_encoding(buf.start, buf.len, language);
}
#endif
#if HAVE_UCHARDET
static const char *mp_uchardet(void *talloc_ctx, struct mp_log *log, bstr buf)
{
uchardet_t det = uchardet_new();
if (!det)
return NULL;
if (uchardet_handle_data(det, buf.start, buf.len) != 0) {
uchardet_delete(det);
return NULL;
}
uchardet_data_end(det);
char *res = talloc_strdup(talloc_ctx, uchardet_get_charset(det));
if (res && !res[0])
res = NULL;
if (res) {
iconv_t icdsc = iconv_open("UTF-8", res);
if (icdsc == (iconv_t)(-1)) {
mp_warn(log, "Charset detected as %s, but not supported by iconv.\n",
res);
res = NULL;
} else {
iconv_close(icdsc);
}
}
if (!res && bstr_validate_utf8(buf) >= 0)
res = "utf-8";
uchardet_delete(det);
return res;
}
#endif
// Runs charset auto-detection on the input buffer, and returns the result.
// If auto-detection fails, NULL is returned.
// If user_cp doesn't refer to any known auto-detection (for example because
// it's a real iconv codepage), user_cp is returned without even looking at
// the buf data.
// The return value may (but doesn't have to) be allocated under talloc_ctx.
const char *mp_charset_guess(void *talloc_ctx, struct mp_log *log, bstr buf,
const char *user_cp, int flags)
{
if (!mp_charset_requires_guess(user_cp))
return user_cp;
bool use_auto = strcasecmp(user_cp, "auto") == 0;
if (use_auto) {
#if HAVE_UCHARDET
user_cp = "uchardet";
#elif HAVE_ENCA
user_cp = "enca";
#else
user_cp = "UTF-8:UTF-8-BROKEN";
#endif
}
bstr params[3] = {{0}};
split_colon(user_cp, 3, params);
bstr type = params[0];
char lang[100];
snprintf(lang, sizeof(lang), "%.*s", BSTR_P(params[1]));
const char *fallback = params[2].start; // last item, already 0-terminated
const char *res = NULL;
if (use_auto) {
res = ms_bom_guess(buf);
if (res)
type = bstr0("auto");
}
#if HAVE_ENCA
if (bstrcasecmp0(type, "enca") == 0)
res = enca_guess(log, buf, lang);
#endif
#if HAVE_LIBGUESS
if (bstrcasecmp0(type, "guess") == 0)
res = libguess_guess(log, buf, lang);
#endif
#if HAVE_UCHARDET
if (bstrcasecmp0(type, "uchardet") == 0)
res = mp_uchardet(talloc_ctx, log, buf);
#endif
if (bstrcasecmp0(type, "utf8") == 0 || bstrcasecmp0(type, "utf-8") == 0) {
if (!fallback)
fallback = params[1].start; // must be already 0-terminated
int r = bstr_validate_utf8(buf);
if (r >= 0 || (r > -8 && (flags & MP_ICONV_ALLOW_CUTOFF)))
res = "utf-8";
}
if (res) {
mp_dbg(log, "%.*s detected charset: '%s'\n", BSTR_P(type), res);
} else {
res = fallback;
mp_dbg(log, "Detection with %.*s failed: fallback to %s\n",
BSTR_P(type), res && res[0] ? res : "broken UTF-8/Latin1");
}
if (!res && !(flags & MP_STRICT_UTF8))
res = "UTF-8-BROKEN";
mp_verbose(log, "Using charset '%s'.\n", res);
return res;
}
// Use iconv to convert buf to UTF-8.
// Returns buf.start==NULL on error. Returns buf if cp is NULL, or if there is
// obviously no conversion required (e.g. if cp is "UTF-8").
// Returns a newly allocated buffer if conversion is done and succeeds. The
// buffer will be terminated with 0 for convenience (the terminating 0 is not
// included in the returned length).
// Free the returned buffer with talloc_free().
// buf: input data
// cp: iconv codepage (or NULL)
// flags: combination of MP_ICONV_* flags
// returns: buf (no conversion), .start==NULL (error), or allocated buffer
bstr mp_iconv_to_utf8(struct mp_log *log, bstr buf, const char *cp, int flags)
{
#if HAVE_ICONV
if (!cp || !cp[0] || mp_charset_is_utf8(cp))
return buf;
if (strcasecmp(cp, "ASCII") == 0)
return buf;
if (strcasecmp(cp, "UTF-8-BROKEN") == 0)
return bstr_sanitize_utf8_latin1(NULL, buf);
iconv_t icdsc;
if ((icdsc = iconv_open("UTF-8", cp)) == (iconv_t) (-1)) {
if (flags & MP_ICONV_VERBOSE)
mp_err(log, "Error opening iconv with codepage '%s'\n", cp);
goto failure;
}
size_t size = buf.len;
size_t osize = size;
size_t ileft = size;
size_t oleft = size - 1;
char *outbuf = talloc_size(NULL, osize);
char *ip = buf.start;
char *op = outbuf;
while (1) {
int clear = 0;
size_t rc;
if (ileft)
rc = iconv(icdsc, &ip, &ileft, &op, &oleft);
else {
clear = 1; // clear the conversion state and leave
rc = iconv(icdsc, NULL, NULL, &op, &oleft);
}
if (rc == (size_t) (-1)) {
if (errno == E2BIG) {
size_t offset = op - outbuf;
outbuf = talloc_realloc_size(NULL, outbuf, osize + size);
op = outbuf + offset;
osize += size;
oleft += size;
} else {
if (errno == EINVAL && (flags & MP_ICONV_ALLOW_CUTOFF)) {
// This is intended for cases where the input buffer is cut
// at a random byte position. If this happens in the middle
// of the buffer, it should still be an error. We say it's
// fine if the error is within 10 bytes of the end.
if (ileft <= 10)
break;
}
if (flags & MP_ICONV_VERBOSE) {
mp_err(log, "Error recoding text with codepage '%s'\n", cp);
}
talloc_free(outbuf);
iconv_close(icdsc);
goto failure;
}
} else if (clear)
break;
}
iconv_close(icdsc);
outbuf[osize - oleft - 1] = 0;
return (bstr){outbuf, osize - oleft - 1};
#endif
failure:
return (bstr){0};
}