[FFmpeg-devel] [PATCH] Long path support for Windows (fixes #8885)
nihil-admirari at tutanota.com
nihil-admirari at tutanota.com
Sun Feb 13 14:28:02 EET 2022
Long path support is enabled by adding a manifest to all of fftools.
MAX_PATH-sized buffers are replaced with dynamically sized ones.
Signed-off-by: nihil-admirari <50202386+nihil-admirari at users.noreply.github.com>
---
compat/w32dlfcn.h | 58 +++++++++++++++++++++++++++-----
fftools/Makefile | 5 +++
fftools/cmdutils.c | 31 +++++++++++++----
fftools/long_paths_utf8.manifest | 12 +++++++
fftools/long_paths_utf8.rc | 3 ++
libavformat/avisynth.c | 10 +++---
libavutil/wchar_filename.h | 37 ++++++++++++++++++++
7 files changed, 136 insertions(+), 20 deletions(-)
create mode 100644 fftools/long_paths_utf8.manifest
create mode 100644 fftools/long_paths_utf8.rc
diff --git a/compat/w32dlfcn.h b/compat/w32dlfcn.h
index 52a94ef..a36e97c 100644
--- a/compat/w32dlfcn.h
+++ b/compat/w32dlfcn.h
@@ -25,6 +25,30 @@
#if (_WIN32_WINNT < 0x0602) || HAVE_WINRT
#include "libavutil/wchar_filename.h"
#endif
+
+static inline wchar_t *get_module_filename(const HMODULE module)
+{
+ wchar_t *path = NULL;
+ int path_size = 0, path_len = 0;
+
+ do {
+ path_size = path_size ? 1.5 * path_size : MAX_PATH;
+ wchar_t *new_path = av_realloc_array(path, path_size, sizeof *path);
+ if (!new_path) {
+ av_free(path);
+ return NULL;
+ }
+ path = new_path;
+ path_len = GetModuleFileNameW(module, path, path_size);
+ } while (path_len && path_size <= 32768 && path_size <= path_len);
+
+ if (!path_len) {
+ av_free(path);
+ return NULL;
+ }
+ return path;
+}
+
/**
* Safe function used to open dynamic libs. This attempts to improve program security
* by removing the current directory from the dll search path. Only dll's found in the
@@ -38,24 +62,40 @@ static inline HMODULE win32_dlopen(const char *name)
// Need to check if KB2533623 is available
if (!GetProcAddress(GetModuleHandleW(L"kernel32.dll"), "SetDefaultDllDirectories")) {
HMODULE module = NULL;
- wchar_t *path = NULL, *name_w = NULL;
- DWORD pathlen;
+ wchar_t *path = NULL, *new_path = NULL, *name_w = NULL;
+ DWORD pathlen, pathsize, namelen;
if (utf8towchar(name, &name_w))
goto exit;
- path = (wchar_t *)av_calloc(MAX_PATH, sizeof(wchar_t));
+ namelen = wcslen(name_w);
// Try local directory first
- pathlen = GetModuleFileNameW(NULL, path, MAX_PATH);
- pathlen = wcsrchr(path, '\\') - path;
- if (pathlen == 0 || pathlen + wcslen(name_w) + 2 > MAX_PATH)
+ path = get_module_filename(NULL);
+ pathlen = path ? wcsrchr(path, '\\') - path : 0;
+ if (pathlen == 0)
+ goto exit;
+ pathsize = pathlen + namelen + 2;
+ new_path = av_realloc_array(path, pathsize, sizeof *path);
+ if (!new_path)
goto exit;
- path[pathlen] = '\\';
+ path = new_path;
wcscpy(path + pathlen + 1, name_w);
module = LoadLibraryExW(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
if (module == NULL) {
// Next try System32 directory
- pathlen = GetSystemDirectoryW(path, MAX_PATH);
- if (pathlen == 0 || pathlen + wcslen(name_w) + 2 > MAX_PATH)
+ pathlen = GetSystemDirectoryW(path, pathsize);
+ if (pathlen == 0)
goto exit;
+ if (pathlen + namelen + 2 > pathsize) {
+ pathsize = pathlen + namelen + 2;
+ new_path = av_realloc_array(path, pathsize, sizeof *path);
+ if (!new_path)
+ goto exit;
+ path = new_path;
+ // The buffer might have been not enough for system directory
+ // in the first place.
+ pathlen = GetSystemDirectoryW(path, pathsize);
+ if (pathlen == 0)
+ goto exit;
+ }
path[pathlen] = '\\';
wcscpy(path + pathlen + 1, name_w);
module = LoadLibraryExW(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
diff --git a/fftools/Makefile b/fftools/Makefile
index da42078..53438b6 100644
--- a/fftools/Makefile
+++ b/fftools/Makefile
@@ -11,6 +11,11 @@ ALLAVPROGS_G = $(AVBASENAMES:%=%$(PROGSSUF)_g$(EXESUF))
OBJS-ffmpeg += fftools/ffmpeg_opt.o fftools/ffmpeg_filter.o fftools/ffmpeg_hw.o
+# Windows resource files
+OBJS-ffmpeg-$(HAVE_GNU_WINDRES) += fftools/long_paths_utf8.o
+OBJS-ffplay-$(HAVE_GNU_WINDRES) += fftools/long_paths_utf8.o
+OBJS-ffprobe-$(HAVE_GNU_WINDRES) += fftools/long_paths_utf8.o
+
define DOFFTOOL
OBJS-$(1) += fftools/cmdutils.o fftools/$(1).o $(OBJS-$(1)-yes)
$(1)$(PROGSSUF)_g$(EXESUF): $$(OBJS-$(1))
diff --git a/fftools/cmdutils.c b/fftools/cmdutils.c
index 4b50e15..ea78897 100644
--- a/fftools/cmdutils.c
+++ b/fftools/cmdutils.c
@@ -62,6 +62,7 @@
#endif
#ifdef _WIN32
#include <windows.h>
+#include "compat/w32dlfcn.h"
#endif
static int init_report(const char *env);
@@ -2065,6 +2066,9 @@ FILE *get_preset_file(char *filename, size_t filename_size,
{
FILE *f = NULL;
int i;
+#if HAVE_GETMODULEHANDLE && defined(_WIN32)
+ char *datadir = NULL;
+#endif
const char *base[3] = { getenv("FFMPEG_DATADIR"),
getenv("HOME"),
FFMPEG_DATADIR, };
@@ -2074,19 +2078,31 @@ FILE *get_preset_file(char *filename, size_t filename_size,
f = fopen(filename, "r");
} else {
#if HAVE_GETMODULEHANDLE && defined(_WIN32)
- char datadir[MAX_PATH], *ls;
+ wchar_t *datadir_w = get_module_filename(NULL);
base[2] = NULL;
- if (GetModuleFileNameA(GetModuleHandleA(NULL), datadir, sizeof(datadir) - 1))
+ if (wchartoansi(datadir_w, &datadir))
+ datadir = NULL;
+ av_free(datadir_w);
+
+ if (datadir)
{
- for (ls = datadir; ls < datadir + strlen(datadir); ls++)
+ char *ls;
+ for (ls = datadir; *ls; ls++)
if (*ls == '\\') *ls = '/';
if (ls = strrchr(datadir, '/'))
{
- *ls = 0;
- strncat(datadir, "/ffpresets", sizeof(datadir) - 1 - strlen(datadir));
- base[2] = datadir;
+ const int datadir_len = ls - datadir;
+ const int desired_size = datadir_len + strlen("/ffpresets") + 1;
+ char *new_datadir = av_realloc_array(
+ datadir, desired_size, sizeof *datadir);
+ if (new_datadir) {
+ datadir = new_datadir;
+ datadir[datadir_len] = 0;
+ strncat(datadir, "/ffpresets", desired_size - 1 - datadir_len);
+ base[2] = datadir;
+ }
}
}
#endif
@@ -2106,6 +2122,9 @@ FILE *get_preset_file(char *filename, size_t filename_size,
}
}
+#if HAVE_GETMODULEHANDLE && defined(_WIN32)
+ av_free(datadir);
+#endif
return f;
}
diff --git a/fftools/long_paths_utf8.manifest b/fftools/long_paths_utf8.manifest
new file mode 100644
index 0000000..d1ac1e4
--- /dev/null
+++ b/fftools/long_paths_utf8.manifest
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+ <assemblyIdentity type="win32" name="FFmpeg" version="1.0.0.0"/>
+ <application xmlns="urn:schemas-microsoft-com:asm.v3">
+ <windowsSettings xmlns:ws2016="http://schemas.microsoft.com/SMI/2016/WindowsSettings"
+ xmlns:ws2019="http://schemas.microsoft.com/SMI/2019/WindowsSettings">
+ <ws2016:longPathAware>true</ws2016:longPathAware>
+ <ws2019:activeCodePage>UTF-8</ws2019:activeCodePage>
+ </windowsSettings>
+ </application>
+</assembly>
diff --git a/fftools/long_paths_utf8.rc b/fftools/long_paths_utf8.rc
new file mode 100644
index 0000000..f33de76
--- /dev/null
+++ b/fftools/long_paths_utf8.rc
@@ -0,0 +1,3 @@
+#include <windows.h>
+
+CREATEPROCESS_MANIFEST_RESOURCE_ID RT_MANIFEST "long_paths_utf8.manifest"
diff --git a/libavformat/avisynth.c b/libavformat/avisynth.c
index 350ac6d..3738cb1 100644
--- a/libavformat/avisynth.c
+++ b/libavformat/avisynth.c
@@ -34,6 +34,7 @@
/* Platform-specific directives. */
#ifdef _WIN32
#include "compat/w32dlfcn.h"
+ #include "libavutil/wchar_filename.h"
#undef EXTERN_C
#define AVISYNTH_LIB "avisynth"
#else
@@ -572,8 +573,7 @@ static int avisynth_open_file(AVFormatContext *s)
AVS_Value arg, val;
int ret;
#ifdef _WIN32
- char filename_ansi[MAX_PATH * 4];
- wchar_t filename_wc[MAX_PATH * 4];
+ char *filename_ansi = NULL;
#endif
if (ret = avisynth_context_create(s))
@@ -581,10 +581,10 @@ static int avisynth_open_file(AVFormatContext *s)
#ifdef _WIN32
/* Convert UTF-8 to ANSI code page */
- MultiByteToWideChar(CP_UTF8, 0, s->url, -1, filename_wc, MAX_PATH * 4);
- WideCharToMultiByte(CP_THREAD_ACP, 0, filename_wc, -1, filename_ansi,
- MAX_PATH * 4, NULL, NULL);
+ if (utf8toansi(s->url, &filename_ansi))
+ goto fail;
arg = avs_new_value_string(filename_ansi);
+ av_free(filename_ansi);
#else
arg = avs_new_value_string(s->url);
#endif
diff --git a/libavutil/wchar_filename.h b/libavutil/wchar_filename.h
index 90f0824..32260a4 100644
--- a/libavutil/wchar_filename.h
+++ b/libavutil/wchar_filename.h
@@ -40,6 +40,43 @@ static inline int utf8towchar(const char *filename_utf8, wchar_t **filename_w)
MultiByteToWideChar(CP_UTF8, 0, filename_utf8, -1, *filename_w, num_chars);
return 0;
}
+
+av_warn_unused_result
+static inline int wchartoansi(const wchar_t *filename_w, char **filename)
+{
+ const int num_chars = WideCharToMultiByte(CP_THREAD_ACP, 0, filename_w, -1,
+ NULL, 0, NULL, NULL);
+ if (num_chars <= 0) {
+ *filename = NULL;
+ return 0;
+ }
+ *filename = (char *)av_calloc(num_chars, sizeof(char));
+ if (!*filename) {
+ errno = ENOMEM;
+ return -1;
+ }
+ WideCharToMultiByte(CP_THREAD_ACP, 0, filename_w, -1,
+ *filename, num_chars, NULL, NULL);
+ return 0;
+}
+
+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;
+}
#endif
#endif /* AVUTIL_WCHAR_FILENAME_H */
--
2.32.0
More information about the ffmpeg-devel
mailing list