SkPDF: Fix Type3 ToUnicode table.

src/pdf/SkPDFMakeToUnicodeCmap.cpp

Index: src/pdf/SkPDFMakeToUnicodeCmap.cpp
diff --git a/src/pdf/SkPDFMakeToUnicodeCmap.cpp b/src/pdf/SkPDFMakeToUnicodeCmap.cpp
index 5186cbbda1955dbda41fcc25ed5600c5d41cb875..7fc5c59be35fcaddffb07522ecd6c1a411821496 100644
--- a/src/pdf/SkPDFMakeToUnicodeCmap.cpp
+++ b/src/pdf/SkPDFMakeToUnicodeCmap.cpp
@@ -10,8 +10,7 @@
 #include "SkUtils.h"
 
 static void append_tounicode_header(SkDynamicMemoryWStream* cmap,
-                                    SkGlyphID firstGlyphID,
-                                    SkGlyphID lastGlyphID) {
+                                    bool multibyte) {
     // 12 dict begin: 12 is an Adobe-suggested value. Shall not change.
     // It's there to prevent old version Adobe Readers from malfunctioning.
     const char* kHeader =
@@ -26,8 +25,8 @@ static void append_tounicode_header(SkDynamicMemoryWStream* cmap,
     // different. This is not a reference object.
     const char* kSysInfo =
         "/CIDSystemInfo\n"
-        "<<  /Registry (Adobe)\n"
-        "/Ordering (UCS)\n"
+        "<<  /Registry (Skia)\n"
+        "/Ordering (SkiaOrdering)\n"

[Rik, 2016/09/01 17:41:21]

Please leave this as-is

         "/Supplement 0\n"
         ">> def\n";
     cmap->writeText(kSysInfo);
@@ -36,18 +35,16 @@ static void append_tounicode_header(SkDynamicMemoryWStream* cmap,
     // /CMapType 2 means ToUnicode.
     // Codespace range just tells the PDF processor the valid range.
     const char* kTypeInfoHeader =
-        "/CMapName /Adobe-Identity-UCS def\n"
+        "/CMapName /Skia-Identity-SkiaOrdering def\n"
         "/CMapType 2 def\n"
         "1 begincodespacerange\n";
     cmap->writeText(kTypeInfoHeader);
-
-    // e.g.     "<0000> <FFFF>\n"
-    SkString range;
-    range.appendf("<%04X> <%04X>\n", firstGlyphID, lastGlyphID);
-    cmap->writeText(range.c_str());
-
-    const char* kTypeInfoFooter = "endcodespacerange\n";
-    cmap->writeText(kTypeInfoFooter);
+    if (multibyte) {
+        cmap->writeText("<0000> <FFFF>\n");
+    } else {
+        cmap->writeText("<00> <FF>\n");
+    }
+    cmap->writeText("endcodespacerange\n");
 }
 
 static void append_cmap_footer(SkDynamicMemoryWStream* cmap) {
@@ -82,7 +79,18 @@ static void write_utf16be(SkDynamicMemoryWStream* wStream, SkUnichar utf32) {
     }
 }
 
+static void write_glyph(SkDynamicMemoryWStream* cmap,
+                        bool multiByte,
+                        SkGlyphID gid) {
+    if (multiByte) {
+        SkPDFUtils::WriteUInt16BE(cmap, gid);
+    } else {
+        SkPDFUtils::WriteUInt8(cmap, SkToU8(gid));
+    }
+}
+
 static void append_bfchar_section(const SkTDArray<BFChar>& bfchar,
+                                  bool multiByte,
                                   SkDynamicMemoryWStream* cmap) {
     // PDF spec defines that every bf* list can have at most 100 entries.
     for (int i = 0; i < bfchar.count(); i += 100) {
@@ -92,7 +100,7 @@ static void append_bfchar_section(const SkTDArray<BFChar>& bfchar,
         cmap->writeText(" beginbfchar\n");
         for (int j = 0; j < count; ++j) {
             cmap->writeText("<");
-            SkPDFUtils::WriteUInt16BE(cmap, bfchar[i + j].fGlyphId);
+            write_glyph(cmap, multiByte, bfchar[i + j].fGlyphId);
             cmap->writeText("> <");
             write_utf16be(cmap, bfchar[i + j].fUnicode);
             cmap->writeText(">\n");
@@ -102,6 +110,7 @@ static void append_bfchar_section(const SkTDArray<BFChar>& bfchar,
 }
 
 static void append_bfrange_section(const SkTDArray<BFRange>& bfrange,
+                                   bool multiByte,
                                    SkDynamicMemoryWStream* cmap) {
     // PDF spec defines that every bf* list can have at most 100 entries.
     for (int i = 0; i < bfrange.count(); i += 100) {
@@ -111,9 +120,9 @@ static void append_bfrange_section(const SkTDArray<BFRange>& bfrange,
         cmap->writeText(" beginbfrange\n");
         for (int j = 0; j < count; ++j) {
             cmap->writeText("<");
-            SkPDFUtils::WriteUInt16BE(cmap, bfrange[i + j].fStart);
+            write_glyph(cmap, multiByte, bfrange[i + j].fStart);
             cmap->writeText("> <");
-            SkPDFUtils::WriteUInt16BE(cmap, bfrange[i + j].fEnd);
+            write_glyph(cmap, multiByte, bfrange[i + j].fEnd);
             cmap->writeText("> <");
             write_utf16be(cmap, bfrange[i + j].fUnicode);
             cmap->writeText(">\n");
@@ -206,8 +215,8 @@ void SkPDFAppendCmapSections(const SkTDArray<SkUnichar>& glyphToUnicode,
 
     // The spec requires all bfchar entries for a font must come before bfrange
     // entries.
-    append_bfchar_section(bfcharEntries, cmap);
-    append_bfrange_section(bfrangeEntries, cmap);
+    append_bfchar_section(bfcharEntries, multiByteGlyphs, cmap);
+    append_bfrange_section(bfrangeEntries, multiByteGlyphs, cmap);
 }
 
 sk_sp<SkPDFStream> SkPDFMakeToUnicodeCmap(
@@ -217,11 +226,7 @@ sk_sp<SkPDFStream> SkPDFMakeToUnicodeCmap(
         SkGlyphID firstGlyphID,
         SkGlyphID lastGlyphID) {
     SkDynamicMemoryWStream cmap;
-    if (multiByteGlyphs) {
-        append_tounicode_header(&cmap, firstGlyphID, lastGlyphID);
-    } else {
-        append_tounicode_header(&cmap, 1, lastGlyphID - firstGlyphID + 1);
-    }
+    append_tounicode_header(&cmap, multiByteGlyphs);
     SkPDFAppendCmapSections(glyphToUnicode, subset, &cmap, multiByteGlyphs,
                             firstGlyphID, lastGlyphID);
     append_cmap_footer(&cmap);