[PATCH 0/1] MR3363: windowscodecs: Handle PNG histogram (hIST) chunk type.

[Jeffrey Smith (＠whydoubt)]

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/3363

[PATCH 1/1] windowscodecs: Handle PNG histogram (hIST) chunk type.

[Jeff Smith]

From: Jeff Smith <whydoubt(a)gmail.com>

---
 dlls/windowscodecs/clsfactory.c               |  1 +
 dlls/windowscodecs/pngformat.c                | 57 ++++++++++++++++++
 dlls/windowscodecs/regsvr.c                   | 25 ++++++++
 dlls/windowscodecs/tests/metadata.c           | 59 +++++++++++++++++++
 dlls/windowscodecs/wincodecs_private.h        |  1 +
 dlls/windowscodecs/windowscodecs_wincodec.idl |  8 +++
 6 files changed, 151 insertions(+)

diff --git a/dlls/windowscodecs/clsfactory.c b/dlls/windowscodecs/clsfactory.c
index d69e5dc4a6d..5065c8f2ca4 100644
--- a/dlls/windowscodecs/clsfactory.c
+++ b/dlls/windowscodecs/clsfactory.c
@@ -65,6 +65,7 @@ static const classinfo wic_classes[] = {
     {&CLSID_WICIfdMetadataReader, IfdMetadataReader_CreateInstance},
     {&CLSID_WICPngChrmMetadataReader, PngChrmReader_CreateInstance},
     {&CLSID_WICPngGamaMetadataReader, PngGamaReader_CreateInstance},
+    {&CLSID_WICPngHistMetadataReader, PngHistReader_CreateInstance},
     {&CLSID_WICPngTextMetadataReader, PngTextReader_CreateInstance},
     {&CLSID_WICLSDMetadataReader, LSDReader_CreateInstance},
     {&CLSID_WICIMDMetadataReader, IMDReader_CreateInstance},
diff --git a/dlls/windowscodecs/pngformat.c b/dlls/windowscodecs/pngformat.c
index b9bdcf1c56e..705496f558e 100644
--- a/dlls/windowscodecs/pngformat.c
+++ b/dlls/windowscodecs/pngformat.c
@@ -30,6 +30,11 @@
 
 #include "wine/debug.h"
 
+static inline USHORT read_ushort_be(BYTE* data)
+{
+    return data[0] << 8 | data[1];
+}
+
 static inline ULONG read_ulong_be(BYTE* data)
 {
     return data[0] << 24 | data[1] << 16 | data[2] << 8 | data[3];
@@ -245,6 +250,58 @@ HRESULT PngChrmReader_CreateInstance(REFIID iid, void** ppv)
     return MetadataReader_Create(&ChrmReader_Vtbl, iid, ppv);
 }
 
+static HRESULT LoadHistMetadata(IStream *stream, const GUID *preferred_vendor,
+    DWORD persist_options, MetadataItem **items, DWORD *item_count)
+{
+    HRESULT hr;
+    BYTE type[4];
+    BYTE *data;
+    ULONG data_size, element_count, i;
+    MetadataItem *result;
+
+    hr = read_png_chunk(stream, type, &data, &data_size);
+    if (FAILED(hr)) return hr;
+
+    element_count = data_size / 2;
+
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem));
+    if (!result) {
+        HeapFree(GetProcessHeap(), 0, data);
+        return E_OUTOFMEMORY;
+    }
+
+    PropVariantInit(&result[0].schema);
+    PropVariantInit(&result[0].id);
+    PropVariantInit(&result[0].value);
+
+    result[0].id.vt = VT_LPWSTR;
+    result[0].id.pwszVal = wcsdup(L"Frequencies");
+
+    result[0].value.vt = VT_UI2|VT_VECTOR;
+    result[0].value.caui.cElems = element_count;
+    result[0].value.caui.pElems = HeapAlloc(GetProcessHeap(), 0, element_count * sizeof(USHORT));
+    for (i = 0; i < element_count; i++)
+        result[0].value.caui.pElems[i] = read_ushort_be(data + i * 2);
+
+    *items = result;
+    *item_count = 1;
+
+    HeapFree(GetProcessHeap(), 0, data);
+
+    return S_OK;
+}
+
+static const MetadataHandlerVtbl HistReader_Vtbl = {
+    0,
+    &CLSID_WICPngHistMetadataReader,
+    LoadHistMetadata
+};
+
+HRESULT PngHistReader_CreateInstance(REFIID iid, void** ppv)
+{
+    return MetadataReader_Create(&HistReader_Vtbl, iid, ppv);
+}
+
 HRESULT PngDecoder_CreateInstance(REFIID iid, void** ppv)
 {
     HRESULT hr;
diff --git a/dlls/windowscodecs/regsvr.c b/dlls/windowscodecs/regsvr.c
index 5aa8b618afa..113fac21603 100644
--- a/dlls/windowscodecs/regsvr.c
+++ b/dlls/windowscodecs/regsvr.c
@@ -1620,6 +1620,21 @@ static const struct reader_containers pngchrm_containers[] = {
     { NULL } /* list terminator */
 };
 
+static const BYTE hIST[] = "hIST";
+
+static const struct metadata_pattern pnghist_metadata_pattern[] = {
+    { 4, 4, hIST, mask_all, 4 },
+    { 0 }
+};
+
+static const struct reader_containers pnghist_containers[] = {
+    {
+        &GUID_ContainerFormatPng,
+        pnghist_metadata_pattern
+    },
+    { NULL } /* list terminator */
+};
+
 static const struct metadata_pattern lsd_metadata_patterns[] = {
     { 0, 6, gif87a_magic, mask_all, 0 },
     { 0, 6, gif89a_magic, mask_all, 0 },
@@ -1735,6 +1750,16 @@ static struct regsvr_metadatareader const metadatareader_list[] = {
         0, 0, 0,
         pnggama_containers
     },
+    {   &CLSID_WICPngHistMetadataReader,
+        "The Wine Project",
+        "Chunk hIST Reader",
+        "1.0.0.0",
+        "1.0.0.0",
+        &GUID_VendorMicrosoft,
+        &GUID_MetadataFormatChunkhIST,
+        0, 0, 0,
+        pnghist_containers
+    },
     {   &CLSID_WICPngTextMetadataReader,
         "The Wine Project",
         "Chunk tEXt Reader",
diff --git a/dlls/windowscodecs/tests/metadata.c b/dlls/windowscodecs/tests/metadata.c
index 1deb09cfd19..de4005443d1 100644
--- a/dlls/windowscodecs/tests/metadata.c
+++ b/dlls/windowscodecs/tests/metadata.c
@@ -158,6 +158,17 @@ static const char metadata_cHRM[] = {
     0xff,0xff,0xff,0xff /* chunk CRC */
 };
 
+static const char metadata_hIST[] = {
+    0,0,0,40, /* chunk length */
+    'h','I','S','T', /* chunk type */
+    0,1,  0,2,  0,3,  0,4,
+    0,5,  0,6,  0,7,  0,8,
+    0,9,  0,10, 0,11, 0,12,
+    0,13, 0,14, 0,15, 0,16,
+    0,17, 0,18, 0,19, 0,20,
+    0xff,0xff,0xff,0xff
+};
+
 static const char pngimage[285] = {
 0x89,0x50,0x4e,0x47,0x0d,0x0a,0x1a,0x0a,0x00,0x00,0x00,0x0d,0x49,0x48,0x44,0x52,
 0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x01,0x08,0x02,0x00,0x00,0x00,0x90,0x77,0x53,
@@ -555,6 +566,53 @@ static void test_metadata_cHRM(void)
     IWICMetadataReader_Release(reader);
 }
 
+static void test_metadata_hIST(void)
+{
+    HRESULT hr;
+    IWICMetadataReader *reader;
+    PROPVARIANT schema, id, value;
+    UINT count, i;
+    GUID format;
+    static const WCHAR Frequencies[] = L"Frequencies";
+
+    PropVariantInit(&schema);
+    PropVariantInit(&id);
+    PropVariantInit(&value);
+
+    hr = CoCreateInstance(&CLSID_WICPngHistMetadataReader, NULL, CLSCTX_INPROC_SERVER,
+        &IID_IWICMetadataReader, (void**)&reader);
+    ok(hr == S_OK || broken(hr == REGDB_E_CLASSNOTREG) /*winxp*/, "CoCreateInstance failed, hr=%lx\n", hr);
+    if (FAILED(hr)) return;
+
+    load_stream((IUnknown*)reader, metadata_hIST, sizeof(metadata_hIST), WICPersistOptionDefault);
+
+    hr = IWICMetadataReader_GetMetadataFormat(reader, &format);
+    ok(hr == S_OK, "GetMetadataFormat failed, hr=%lx\n", hr);
+    ok(IsEqualGUID(&format, &GUID_MetadataFormatChunkhIST), "unexpected format %s\n", wine_dbgstr_guid(&format));
+
+    hr = IWICMetadataReader_GetCount(reader, &count);
+    ok(hr == S_OK, "GetCount failed, hr=%lx\n", hr);
+    ok(count == 1, "unexpected count %i\n", count);
+
+    hr = IWICMetadataReader_GetValueByIndex(reader, 0, &schema, &id, &value);
+    ok(hr == S_OK, "GetValue failed, hr=%lx\n", hr);
+
+    ok(schema.vt == VT_EMPTY, "unexpected vt: %i\n", schema.vt);
+    PropVariantClear(&schema);
+
+    ok(id.vt == VT_LPWSTR, "unexpected vt: %i\n", id.vt);
+    ok(!lstrcmpW(U(id).pwszVal, Frequencies), "unexpected value: %s\n", wine_dbgstr_w(U(id).pwszVal));
+    PropVariantClear(&id);
+
+    ok(value.vt == (VT_UI2|VT_VECTOR), "unexpected vt: %i\n", value.vt);
+    ok(20 == U(value).caui.cElems, "expected cElems %d, got %ld\n", 20, U(value).caub.cElems);
+    for (i = 0; i < U(value).caui.cElems; i++)
+        ok(i+1 == U(value).caui.pElems[i], "%u: expected value %u, got %u\n", i, i+1, U(value).caui.pElems[i]);
+    PropVariantClear(&value);
+
+    IWICMetadataReader_Release(reader);
+}
+
 static inline USHORT ushort_bswap(USHORT s)
 {
     return (s >> 8) | (s << 8);
@@ -3213,6 +3271,7 @@ START_TEST(metadata)
     test_metadata_tEXt();
     test_metadata_gAMA();
     test_metadata_cHRM();
+    test_metadata_hIST();
     test_metadata_IFD();
     test_metadata_Exif();
     test_create_reader();
diff --git a/dlls/windowscodecs/wincodecs_private.h b/dlls/windowscodecs/wincodecs_private.h
index 9530325358c..3dcb20786f2 100644
--- a/dlls/windowscodecs/wincodecs_private.h
+++ b/dlls/windowscodecs/wincodecs_private.h
@@ -219,6 +219,7 @@ extern HRESULT UnknownMetadataReader_CreateInstance(REFIID iid, void** ppv);
 extern HRESULT IfdMetadataReader_CreateInstance(REFIID iid, void **ppv);
 extern HRESULT PngChrmReader_CreateInstance(REFIID iid, void** ppv);
 extern HRESULT PngGamaReader_CreateInstance(REFIID iid, void** ppv);
+extern HRESULT PngHistReader_CreateInstance(REFIID iid, void** ppv);
 extern HRESULT PngTextReader_CreateInstance(REFIID iid, void** ppv);
 extern HRESULT LSDReader_CreateInstance(REFIID iid, void **ppv);
 extern HRESULT IMDReader_CreateInstance(REFIID iid, void **ppv);
diff --git a/dlls/windowscodecs/windowscodecs_wincodec.idl b/dlls/windowscodecs/windowscodecs_wincodec.idl
index ca467226dff..e60111ed19c 100644
--- a/dlls/windowscodecs/windowscodecs_wincodec.idl
+++ b/dlls/windowscodecs/windowscodecs_wincodec.idl
@@ -174,10 +174,18 @@ coclass WICPngChrmMetadataReader { interface IWICMetadataReader; }
 ]
 coclass WICPngGamaMetadataReader { interface IWICMetadataReader; }
 
+[
+    helpstring("WIC Png hIST Metadata Reader"),
+    threading(both),
+    uuid(877a0bb7-a313-4491-87b5-2e6d0594f520)
+]
+coclass WICPngHistMetadataReader { interface IWICMetadataReader; }
+
 [
     helpstring("WIC Png tEXt Metadata Reader"),
     threading(both),
     uuid(4b59afcc-b8c3-408a-b670-89e5fab6fda7)
+
 ]
 coclass WICPngTextMetadataReader { interface IWICMetadataReader; }
 
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/3363

[Esme Povirk (＠madewokherd)]

So I noticed while checking this that all of the current metadata handlers are wrong. PropVariantClear uses CoTaskMemFree, so we should be allocating values using CoTaskMemAlloc.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/3363#note_39838