| Message ID | 20220619114056.5582-1-nil-admirari@mailo.com |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel,v19,1/5] libavutil: Add wchartoutf8(), wchartoansi(), utf8toansi(), getenv_utf8() and freeenv_utf8() | expand |
| Context | Check | Description |
|---|---|---|
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
On Sun, 19 Jun 2022, Nil Admirari wrote: > wchartoutf8() converts strings returned by WinAPI into UTF-8, > which is FFmpeg's preffered encoding. > > Some external dependencies, such as AviSynth, are still > not Unicode-enabled. utf8toansi() converts UTF-8 strings > into ANSI in two steps: UTF-8 -> wchar_t -> ANSI. > wchartoansi() is responsible for the second step of the conversion. > Conversion in just one step is not supported by WinAPI. > > Since these character converting functions allocate the buffer > of necessary size, they also facilitate the removal of MAX_PATH limit > in places where fixed-size ANSI/WCHAR strings were used > as filename buffers. > > getenv_utf8() wraps _wgetenv() converting its input from > and its output to UTF-8. Compared to plain getenv(), > getenv_utf8() requires a cleanup. > > Because of that, in places that only test the existence of > an environment variable or compare its value with a string > consisting entirely of ASCII characters, the use of plain getenv() > is still preferred. (libavutil/log.c check_color_terminal() > is an example of such a place.) > > Plain getenv() is also preffered in UNIX-only code, > such as bktr.c, fbdev_common.c, oss.c in libavdevice > or af_ladspa.c in libavfilter. > --- > configure | 1 + > libavutil/getenv_utf8.h | 83 ++++++++++++++++++++++++++++++++++++++ > libavutil/wchar_filename.h | 53 ++++++++++++++++++++++++ > 3 files changed, 137 insertions(+) > create mode 100644 libavutil/getenv_utf8.h Looks good overall, thanks! The freeenv_utf8 function needed a couple minor fixes though, to fix these warnings/errors: src/libavutil/getenv_utf8.h: In function ‘freeenv_utf8’: src/libavutil/getenv_utf8.h:59:13: warning: passing argument 1 of ‘av_free’ discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers] 59 | av_free(var); In file included from src/libavformat/http.c:32: src/libavutil/getenv_utf8.h: In function ‘freeenv_utf8’: src/libavutil/getenv_utf8.h:69:33: error: parameter name omitted 69 | static inline void freeenv_utf8(char *) Fixed locally with these changes: @@ -54,7 +54,7 @@ static inline char *getenv_utf8(const char *varname) // non UTF-8 strings must not be returned. } -static inline void freeenv_utf8(const char *var) +static inline void freeenv_utf8(char *var) { av_free(var); } @@ -66,7 +66,7 @@ static inline char *getenv_utf8(const char *varname) return getenv(varname); } -static inline void freeenv_utf8(const char *) +static inline void freeenv_utf8(char *var) { } (No need to resend for these changes IMO.) If there's no further comments, I'd push this set tomorrow, with these changes amended. // Martin
> Looks good overall, thanks! The freeenv_utf8 function needed a couple > minor fixes though, to fix these warnings/errors: Fixed: https://ffmpeg.org/pipermail/ffmpeg-devel/2022-June/297841.html
diff --git a/configure b/configure index 7ffbb85e21..3a97610209 100755 --- a/configure +++ b/configure @@ -2272,6 +2272,7 @@ SYSTEM_FUNCS=" fcntl getaddrinfo getauxval + getenv gethrtime getopt GetModuleHandle diff --git a/libavutil/getenv_utf8.h b/libavutil/getenv_utf8.h new file mode 100644 index 0000000000..799fef9839 --- /dev/null +++ b/libavutil/getenv_utf8.h @@ -0,0 +1,83 @@ +/* + * This file is part of FFmpeg. + * + * FFmpeg 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. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef AVUTIL_GETENV_UTF8_H +#define AVUTIL_GETENV_UTF8_H + +#include <stdlib.h> + +#include "config.h" +#include "mem.h" + +#if HAVE_GETENV + +#ifdef _WIN32 + +#include "libavutil/wchar_filename.h" + +static inline char *getenv_utf8(const char *varname) +{ + wchar_t *varname_w, *var_w; + char *var; + + if (utf8towchar(varname, &varname_w)) + return NULL; + if (!varname_w) + return NULL; + + var_w = _wgetenv(varname_w); + av_free(varname_w); + + if (!var_w) + return NULL; + if (wchartoutf8(var_w, &var)) + return NULL; + + return var; + + // No CP_ACP fallback compared to other *_utf8() functions: + // non UTF-8 strings must not be returned. +} + +static inline void freeenv_utf8(const char *var) +{ + av_free(var); +} + +#else + +static inline char *getenv_utf8(const char *varname) +{ + return getenv(varname); +} + +static inline void freeenv_utf8(const char *) +{ +} + +#endif // _WIN32 + +#else + +#define getenv_utf8(x) NULL + +#define freeenv_utf8(x) ((void) 0) + +#endif // HAVE_GETENV + +#endif // AVUTIL_GETENV_UTF8_H diff --git a/libavutil/wchar_filename.h b/libavutil/wchar_filename.h index f36d9dfea3..08de073ed7 100644 --- a/libavutil/wchar_filename.h +++ b/libavutil/wchar_filename.h @@ -20,6 +20,8 @@ #define AVUTIL_WCHAR_FILENAME_H #ifdef _WIN32 + +#define WIN32_LEAN_AND_MEAN #include <windows.h> #include "mem.h" @@ -41,6 +43,57 @@ static inline int utf8towchar(const char *filename_utf8, wchar_t **filename_w) return 0; } +av_warn_unused_result +static inline int wchartocp(unsigned int code_page, const wchar_t *filename_w, + char **filename) +{ + DWORD flags = code_page == CP_UTF8 ? WC_ERR_INVALID_CHARS : 0; + int num_chars = WideCharToMultiByte(code_page, flags, filename_w, -1, + NULL, 0, NULL, NULL); + if (num_chars <= 0) { + *filename = NULL; + return 0; + } + *filename = av_malloc_array(num_chars, sizeof *filename); + if (!*filename) { + errno = ENOMEM; + return -1; + } + WideCharToMultiByte(code_page, flags, filename_w, -1, + *filename, num_chars, NULL, NULL); + return 0; +} + +av_warn_unused_result +static inline int wchartoutf8(const wchar_t *filename_w, char **filename) +{ + return wchartocp(CP_UTF8, filename_w, filename); +} + +av_warn_unused_result +static inline int wchartoansi(const wchar_t *filename_w, char **filename) +{ + return wchartocp(CP_ACP, filename_w, filename); +} + +av_warn_unused_result +static inline int utf8toansi(const char *filename_utf8, char **filename) +{ + wchar_t *filename_w = NULL; + int ret = -1; + if (utf8towchar(filename_utf8, &filename_w)) + return -1; + + if (!filename_w) { + *filename = NULL; + return 0; + } + + ret = wchartoansi(filename_w, filename); + av_free(filename_w); + return ret; +} + /** * Checks for extended path prefixes for which normalization needs to be skipped. * see .NET6: PathInternal.IsExtended()