ommit 4ae420734990ab9f5ccc038262368256b9323f4a
Merge: b66799f 994c1c7
Author: Evgeniy Dushistov <dushistov@mail.ru>
Date:   Wed Dec 23 04:30:13 2020 +0300

    Merge pull request #67 from doozan/master

    Use binary search for synonyms, fixes #31

diff --git a/src/stardict_lib.cpp b/src/stardict_lib.cpp
index 0af4304..6b1f92b 100644
--- a/src/stardict_lib.cpp
+++ b/src/stardict_lib.cpp
@@ -833,21 +833,23 @@ bool SynFile::load(const std::string &url, gulong wc)
 {
     struct stat stat_buf;
     if (!stat(url.c_str(), &stat_buf)) {
-        MapFile syn;
-        if (!syn.open(url.c_str(), stat_buf.st_size))
+
+        if (!synfile.open(url.c_str(), stat_buf.st_size))
             return false;
-        const gchar *current = syn.begin();
+
+        synlist.resize(wc + 1);
+        gchar *p1 = synfile.begin();
+
         for (unsigned long i = 0; i < wc; i++) {
             // each entry in a syn-file is:
             // - 0-terminated string
             // 4-byte index into .dict file in network byte order
-            glib::CharStr lower_string{ g_utf8_casefold(current, -1) };
-            std::string synonym{ get_impl(lower_string) };
-            current += synonym.length() + 1;
-            const guint32 idx = g_ntohl(get_uint32(current));
-            current += sizeof(idx);
-            synonyms[synonym] = idx;
+
+            synlist[i] = p1;
+            p1 += strlen(p1) + 1 + 4;
         }
+        synlist[wc] = p1;
+
         return true;
     } else {
         return false;
@@ -856,13 +858,38 @@ bool SynFile::load(const std::string &url, gulong wc)
 
 bool SynFile::lookup(const char *str, glong &idx)
 {
-    glib::CharStr lower_string{ g_utf8_casefold(str, -1) };
-    auto it = synonyms.find(get_impl(lower_string));
-    if (it != synonyms.end()) {
-        idx = it->second;
-        return true;
+    bool bFound = false;
+    glong iTo = synlist.size() - 2;
+    if (iTo <0) return false;
+
+    if (stardict_strcmp(str, get_key(0)) < 0) {
+        idx = 0;
+    } else if (stardict_strcmp(str, get_key(iTo)) > 0) {
+        idx = INVALID_INDEX;
+    } else {
+        glong iThisIndex = 0;
+        glong iFrom = 0;
+        gint cmpint;
+        while (iFrom <= iTo) {
+            iThisIndex = (iFrom + iTo) / 2;
+            cmpint = stardict_strcmp(str, get_key(iThisIndex));
+            if (cmpint > 0)
+                iFrom = iThisIndex + 1;
+            else if (cmpint < 0)
+                iTo = iThisIndex - 1;
+            else {
+                bFound = true;
+                break;
+            }
+        }
+        if (!bFound)
+            idx = iFrom; //next
+        else {
+            const gchar *key = get_key(iThisIndex);
+            idx = g_ntohl(get_uint32(key+strlen(key)+1));
+        }
     }
-    return false;
+    return bFound;
 }
 
 bool Dict::Lookup(const char *str, glong &idx)
diff --git a/src/stardict_lib.hpp b/src/stardict_lib.hpp
index a629cbe..38f76f4 100644
--- a/src/stardict_lib.hpp
+++ b/src/stardict_lib.hpp
@@ -102,11 +102,15 @@ public:
 class SynFile
 {
 public:
+    SynFile() {}
+    ~SynFile() {}
     bool load(const std::string &url, gulong wc);
     bool lookup(const char *str, glong &idx);
+    const gchar *get_key(glong idx) { return synlist[idx]; }
 
 private:
-    std::map<std::string, gulong> synonyms;
+    MapFile synfile;
+    std::vector<gchar *> synlist;
 };
 
 class Dict : public DictBase