version 0.5.5

Avoid crashes when passing unknown dicts to the -u flag

Fix #87

.clang-format

@@ -15,7 +15,7 @@ BreakBeforeBinaryOperators: true
 BreakBeforeTernaryOperators: true
 BreakConstructorInitializersBeforeComma: true
 BinPackParameters: true
-ColumnLimit:     0
+ColumnLimit:     120
 ConstructorInitializerAllOnOneLineOrOnePerLine: false
 DerivePointerAlignment: false
 ExperimentalAutoDetectBinPacking: false

.github/workflows/main.yml

@@ -20,12 +20,13 @@ jobs:
       fail-fast: true
 
       matrix:
-        os: [ubuntu-latest]
+        os: [ubuntu-20.04, ubuntu-latest]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: 'recursive'
-      - uses: jwlawson/actions-setup-cmake@v1.0
+      - uses: jwlawson/actions-setup-cmake@v1.4
+        if: matrix.os != 'ubuntu-latest'
         with:
           cmake-version: '3.5.1'
           github-api-token: ${{ secrets.GITHUB_TOKEN }}

CMakeLists.txt

@@ -3,6 +3,10 @@ project(sdcv)
 cmake_minimum_required(VERSION 3.5 FATAL_ERROR)
 cmake_policy(VERSION 3.5)
 
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED True)
+set(CMAKE_CXX_EXTENSIONS False)
+
 include("${CMAKE_CURRENT_SOURCE_DIR}/cmake/compiler.cmake")
 
 set(ZLIB_FIND_REQUIRED True)
@@ -91,7 +95,7 @@ set(CPACK_PACKAGE_VENDOR "Evgeniy Dushistov <dushistov@mail.ru>")
 set(CPACK_PACKAGE_DESCRIPTION_FILE "${CMAKE_CURRENT_SOURCE_DIR}/README.org")
 set(CPACK_PACKAGE_VERSION_MAJOR "0")
 set(CPACK_PACKAGE_VERSION_MINOR "5")
-set(CPACK_PACKAGE_VERSION_PATCH "3")
+set(CPACK_PACKAGE_VERSION_PATCH "5")
 
 set(sdcv_VERSION
 	"${CPACK_PACKAGE_VERSION_MAJOR}.${CPACK_PACKAGE_VERSION_MINOR}.${CPACK_PACKAGE_VERSION_PATCH}")
@@ -143,5 +147,7 @@ if (BUILD_TESTS)
   add_sdcv_shell_test(t_utf8input)
   add_sdcv_shell_test(t_datadir)
   add_sdcv_shell_test(t_return_code)
+  add_sdcv_shell_test(t_multiple_results)
+  add_sdcv_shell_test(t_newlines_in_ifo)
 
 endif (BUILD_TESTS)

NEWS

@@ -1,3 +1,13 @@
+Version 0.5.5
+    - Avoid crashes when passing unknown dicts to the -u flag (by NiLuJe)
+    - Use off_t for stuff mainly assigned to a stat.st_size value
+Version 0.5.4
+    - Use binary search for synonyms
+    - Various improvments in work with synonyms
+    - Added --json (same as --json-output) to match man
+    - Show all matched result
+    - More robust parsing of ifo file
+    - Prevent crash if file size of files not matched expecting one for .oft files
 Version 0.5.3
   - Use single quotes around JSON data to reduce need for escaping
   - Store integer magic in cache file

README.org

@@ -1,6 +1,9 @@
 #+OPTIONS: ^:nil
 [[https://github.com/Dushistov/sdcv/actions?query=workflow%3ACI+branch%3Amaster][https://github.com/Dushistov/sdcv/workflows/CI/badge.svg]]
 [[https://github.com/Dushistov/sdcv/blob/master/LICENSE][https://img.shields.io/badge/license-GPL%202-brightgreen.svg]]
+
+* sdcv
+*sdcv* is a simple, cross-platform, text-based utility for working with dictionaries in [[http://stardict-4.sourceforge.net/][StarDict]] format.
 * How to compile and install
 #+BEGIN_SRC sh
 mkdir /tmp/build-sdcv

cmake/compiler.cmake

@@ -16,19 +16,6 @@ if (NOT DEFINED SDCV_COMPILER_IS_GCC_COMPATIBLE)
   endif()
 endif()
 
-if (MSVC AND (MSVC_VERSION LESS 1900))
-  message(FATAL_ERROR "MSVC version ${MSVC_VERSION} have no full c++11 support")
-elseif (MSVC)
-  add_definitions(-DNOMINMAX)
-elseif (NOT MSVC)
-  check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11)
-  if (CXX_SUPPORTS_CXX11)
-    append("-std=c++11" CMAKE_CXX_FLAGS)
-  else ()
-    message(FATAL_ERROR "sdcv requires C++11 support but the '-std=c++11' flag isn't supported.")
-  endif()
-endif ()
-
 if (SDCV_COMPILER_IS_GCC_COMPATIBLE)
   append("-Wall" "-Wextra" "-Wformat-security" "-Wcast-align" "-Werror=format" "-Wcast-qual" CMAKE_C_FLAGS)
   append("-Wall" "-pedantic" "-Wextra" "-Wformat-security" "-Wcast-align" "-Werror=format" "-Wcast-qual" CMAKE_CXX_FLAGS)

src/dictziplib.hpp

@@ -27,7 +27,7 @@ public:
 private:
     const char *start; /* start of mmap'd area */
     const char *end; /* end of mmap'd area */
-    unsigned long size; /* size of mmap */
+    off_t size; /* size of mmap */
 
     int type;
     z_stream zStream;
@@ -47,7 +47,7 @@ private:
     std::string origFilename;
     std::string comment;
     unsigned long crc;
-    unsigned long length;
+    off_t length;
     unsigned long compressedLength;
     DictCache cache[DICT_CACHE_SIZE];
     MapFile mapfile;

src/libwrapper.cpp

@@ -199,14 +199,18 @@ static std::string parse_data(const gchar *data, bool colorize_output)
 
 void Library::SimpleLookup(const std::string &str, TSearchResultList &res_list)
 {
-    glong ind;
+    std::set<glong> wordIdxs;
     res_list.reserve(ndicts());
-    for (gint idict = 0; idict < ndicts(); ++idict)
-        if (SimpleLookupWord(str.c_str(), ind, idict))
+    for (gint idict = 0; idict < ndicts(); ++idict) {
+        wordIdxs.clear();
+        if (SimpleLookupWord(str.c_str(), wordIdxs, idict))
+            for (auto &wordIdx : wordIdxs)
                 res_list.push_back(
                     TSearchResult(dict_name(idict),
-                              poGetWord(ind, idict),
-                              parse_data(poGetWordData(ind, idict), colorize_output_)));
+                                  poGetWord(wordIdx, idict),
+                                  parse_data(poGetWordData(wordIdx, idict),
+                                             colorize_output_)));
+    }
 }
 
 void Library::LookupWithFuzzy(const std::string &str, TSearchResultList &res_list)

src/mapfile.hpp

@@ -7,6 +7,7 @@
 #ifdef HAVE_MMAP
 #include <fcntl.h>
 #include <sys/mman.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #endif
 #ifdef _WIN32
@@ -21,13 +22,13 @@ public:
     ~MapFile();
     MapFile(const MapFile &) = delete;
     MapFile &operator=(const MapFile &) = delete;
-    bool open(const char *file_name, unsigned long file_size);
+    bool open(const char *file_name, off_t file_size);
     gchar *begin() { return data; }
 
 private:
     char *data = nullptr;
-    unsigned long size = 0ul;
 #ifdef HAVE_MMAP
+    size_t size = 0u;
     int mmap_fd = -1;
 #elif defined(_WIN32)
     HANDLE hFile = 0;
@@ -35,25 +36,31 @@ private:
 #endif
 };
 
-inline bool MapFile::open(const char *file_name, unsigned long file_size)
+inline bool MapFile::open(const char *file_name, off_t file_size)
 {
-    size = file_size;
 #ifdef HAVE_MMAP
     if ((mmap_fd = ::open(file_name, O_RDONLY)) < 0) {
         // g_print("Open file %s failed!\n",fullfilename);
         return false;
     }
-    data = (gchar *)mmap(nullptr, file_size, PROT_READ, MAP_SHARED, mmap_fd, 0);
+    struct stat st;
+    if (fstat(mmap_fd, &st) == -1 || st.st_size < 0 || (st.st_size == 0 && S_ISREG(st.st_mode))
+        || st.st_size != file_size) {
+        close(mmap_fd);
+        return false;
+    }
+
+    size = static_cast<size_t>(st.st_size);
+    data = (gchar *)mmap(nullptr, size, PROT_READ, MAP_SHARED, mmap_fd, 0);
     if ((void *)data == (void *)(-1)) {
         // g_print("mmap file %s failed!\n",idxfilename);
+        size = 0u;
         data = nullptr;
         return false;
     }
 #elif defined(_WIN32)
-    hFile = CreateFile(file_name, GENERIC_READ, 0, nullptr, OPEN_ALWAYS,
-                       FILE_ATTRIBUTE_NORMAL, 0);
-    hFileMap = CreateFileMapping(hFile, nullptr, PAGE_READONLY, 0,
-                                 file_size, nullptr);
+    hFile = CreateFile(file_name, GENERIC_READ, 0, nullptr, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
+    hFileMap = CreateFileMapping(hFile, nullptr, PAGE_READONLY, 0, file_size, nullptr);
     data = (gchar *)MapViewOfFile(hFileMap, FILE_MAP_READ, 0, 0, file_size);
 #else
     gsize read_len;

src/sdcv.cpp

@@ -83,6 +83,7 @@ try {
     glib::CharStr opt_data_dir;
     gboolean only_data_dir = FALSE;
     gboolean colorize = FALSE;
+    glib::StrArr word_list;
 
     const GOptionEntry entries[] = {
         { "version", 'v', 0, G_OPTION_ARG_NONE, &show_version,
@@ -96,6 +97,8 @@ try {
           _("for use in scripts"), nullptr },
         { "json-output", 'j', 0, G_OPTION_ARG_NONE, &json_output,
           _("print the result formatted as JSON"), nullptr },
+        { "json", 'j', 0, G_OPTION_ARG_NONE, &json_output,
+          _("print the result formatted as JSON"), nullptr },
         { "exact-search", 'e', 0, G_OPTION_ARG_NONE, &no_fuzzy,
           _("do not fuzzy-search for similar words, only return exact matches"), nullptr },
         { "utf8-output", '0', 0, G_OPTION_ARG_NONE, &utf8_output,
@@ -109,11 +112,13 @@ try {
           _("only use the dictionaries in data-dir, do not search in user and system directories"), nullptr },
         { "color", 'c', 0, G_OPTION_ARG_NONE, &colorize,
           _("colorize the output"), nullptr },
+        { G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, get_addr(word_list),
+          _("search terms"), _(" words") },
         {},
     };
 
     glib::Error error;
-    GOptionContext *context = g_option_context_new(_(" words"));
+    GOptionContext *context = g_option_context_new(nullptr);
     g_option_context_set_help_enabled(context, TRUE);
     g_option_context_add_main_entries(context, entries, nullptr);
     const gboolean parse_res = g_option_context_parse(context, &argc, &argv, get_addr(error));
@@ -181,10 +186,13 @@ try {
         }
 
         // add bookname to list
-        gchar **p = get_impl(use_dict_list);
-        while (*p) {
-            order_list.push_back(bookname_to_ifo.at(*p));
-            ++p;
+        for (gchar **p = get_impl(use_dict_list); *p != nullptr; ++p) {
+            auto it = bookname_to_ifo.find(*p);
+            if (it != bookname_to_ifo.end()) {
+                order_list.push_back(it->second);
+            } else {
+                fprintf(stderr, _("Unknown dictionary: %s\n"), *p);
+            }
         }
     } else {
         std::string ordering_cfg_file = std::string(g_get_user_config_dir()) + G_DIR_SEPARATOR_S "sdcv_ordering";
@@ -196,7 +204,12 @@ try {
         if (ordering_file != nullptr) {
             std::string line;
             while (stdio_getline(ordering_file, line)) {
-                order_list.push_back(bookname_to_ifo.at(line));
+                auto it = bookname_to_ifo.find(line);
+                if (it != bookname_to_ifo.end()) {
+                    order_list.push_back(it->second);
+                } else {
+                    fprintf(stderr, _("Unknown dictionary: %s\n"), line.c_str());
+                }
             }
             fclose(ordering_file);
         }
@@ -210,14 +223,19 @@ try {
     lib.load(dicts_dir_list, order_list, disable_list);
 
     std::unique_ptr<IReadLine> io(create_readline_object());
-    if (optind < argc) {
+    if (word_list != nullptr) {
         search_result rval = SEARCH_SUCCESS;
-        for (int i = optind; i < argc; ++i)
-            if ((rval = lib.process_phrase(argv[i], *io, non_interactive)) != SEARCH_SUCCESS) {
-                return rval;
+        gchar **p = get_impl(word_list);
+        while (*p) {
+            search_result this_rval = lib.process_phrase(*p++, *io, non_interactive);
+            // If we encounter any error, save it but continue through the word
+            // list to check all requested words.
+            if (rval == SEARCH_SUCCESS)
+                rval = this_rval;
         }
+        if (rval != SEARCH_SUCCESS)
+            return rval;
     } else if (!non_interactive) {
-
         std::string phrase;
         while (io->read(_("Enter word or phrase: "), phrase)) {
             if (lib.process_phrase(phrase.c_str(), *io) == SEARCH_FAILURE)

src/stardict_lib.cpp

@@ -5,6 +5,7 @@
 #include <algorithm>
 #include <cctype>
 #include <cstring>
+#include <map>
 #include <stdexcept>
 
 #include <glib/gstdio.h>
@@ -78,108 +79,93 @@ bool DictInfo::load_from_ifo_file(const std::string &ifofilename,
 {
     ifo_file_name = ifofilename;
     glib::CharStr buffer;
-    if (!g_file_get_contents(ifofilename.c_str(), get_addr(buffer), nullptr, nullptr))
+    gsize length = 0;
+    if (!g_file_get_contents(ifofilename.c_str(), get_addr(buffer), &length, nullptr)) {
+        fprintf(stderr, "Can not read from %s\n", ifofilename.c_str());
         return false;
+    }
 
     static const char TREEDICT_MAGIC_DATA[] = "StarDict's treedict ifo file";
     static const char DICT_MAGIC_DATA[] = "StarDict's dict ifo file";
 
     const gchar *magic_data = istreedict ? TREEDICT_MAGIC_DATA : DICT_MAGIC_DATA;
-    static const unsigned char utf8_bom[] = { 0xEF, 0xBB, 0xBF, '\0' };
-    if (!g_str_has_prefix(
-            g_str_has_prefix(get_impl(buffer), (const gchar *)(utf8_bom)) ? get_impl(buffer) + 3 : get_impl(buffer),
-            magic_data)) {
+    static const gchar utf8_bom[] = { (gchar)0xEF, (gchar)0xBB, (gchar)0xBF, '\0' };
+
+    const gchar *p = get_impl(buffer);
+    const gchar *end = p + length;
+
+    if (g_str_has_prefix(p, utf8_bom)) {
+        p += strlen(utf8_bom);
+    }
+    if (!g_str_has_prefix(p, magic_data)) {
+        fprintf(stderr, "No magic header(%s) in ifo file\n", magic_data);
         return false;
     }
+    p += strlen(magic_data);
 
-    gchar *p1 = get_impl(buffer) + strlen(magic_data) - 1;
-
-    gchar *p2 = strstr(p1, "\nwordcount=");
-    if (p2 == nullptr)
+    std::map<std::string, std::string> key_value_map;
+    while (p != end) {
+        auto key_it = std::find_if(p, end, [](gchar ch) { return !g_ascii_isspace(ch); });
+        if (key_it == end) {
+            break;
+        }
+        auto eq_it = std::find(key_it, end, gchar('='));
+        if (eq_it == end) {
+            fprintf(stderr, "Invalid part of ifo (no '=') here: %s\n", key_it);
             return false;
+        }
+        auto val_it = std::find_if(eq_it + 1, end, [](gchar ch) { return !g_ascii_isspace(ch); });
+        if (val_it == end) {
+            key_value_map.insert(std::make_pair(std::string(key_it, eq_it), std::string()));
+            break;
+        }
 
-    gchar *p3 = strchr(p2 + sizeof("\nwordcount=") - 1, '\n');
+        auto line_end_it = std::find_if(val_it, end, [](gchar ch) { return ch == '\r' || ch == '\n'; });
+        key_value_map.insert(std::make_pair(std::string(key_it, eq_it), std::string(val_it, line_end_it)));
+        if (line_end_it == end)
+            break;
+        p = line_end_it + 1;
+    }
 
-    wordcount = atol(std::string(p2 + sizeof("\nwordcount=") - 1, p3 - (p2 + sizeof("\nwordcount=") - 1)).c_str());
+    std::map<std::string, std::string>::const_iterator it;
+#define FIND_KEY(_key_)                                            \
+    it = key_value_map.find(_key_);                                \
+    if (it == key_value_map.end()) {                               \
+        fprintf(stderr, "Can not find '%s' in ifo file\n", _key_); \
+        return false;                                              \
+    }
+
+    FIND_KEY("wordcount")
+    wordcount = atol(it->second.c_str());
 
     if (istreedict) {
-        p2 = strstr(p1, "\ntdxfilesize=");
-        if (p2 == nullptr)
-            return false;
-
-        p3 = strchr(p2 + sizeof("\ntdxfilesize=") - 1, '\n');
-
-        index_file_size = atol(std::string(p2 + sizeof("\ntdxfilesize=") - 1, p3 - (p2 + sizeof("\ntdxfilesize=") - 1)).c_str());
-
+        FIND_KEY("tdxfilesize")
+        index_file_size = atol(it->second.c_str());
     } else {
+        FIND_KEY("idxfilesize")
+        index_file_size = atol(it->second.c_str());
+    }
+    FIND_KEY("bookname")
+    bookname = it->second;
 
-        p2 = strstr(p1, "\nidxfilesize=");
-        if (p2 == nullptr)
-            return false;
-
-        p3 = strchr(p2 + sizeof("\nidxfilesize=") - 1, '\n');
-        index_file_size = atol(std::string(p2 + sizeof("\nidxfilesize=") - 1, p3 - (p2 + sizeof("\nidxfilesize=") - 1)).c_str());
+#define SET_IF_EXISTS(_key_)         \
+    it = key_value_map.find(#_key_); \
+    if (it != key_value_map.end()) { \
+        _key_ = it->second;          \
     }
 
-    p2 = strstr(p1, "\nbookname=");
-
-    if (p2 == nullptr)
-        return false;
-
-    p2 = p2 + sizeof("\nbookname=") - 1;
-    p3 = strchr(p2, '\n');
-    bookname.assign(p2, p3 - p2);
-
-    p2 = strstr(p1, "\nauthor=");
-    if (p2) {
-        p2 = p2 + sizeof("\nauthor=") - 1;
-        p3 = strchr(p2, '\n');
-        author.assign(p2, p3 - p2);
-    }
-
-    p2 = strstr(p1, "\nemail=");
-    if (p2) {
-        p2 = p2 + sizeof("\nemail=") - 1;
-        p3 = strchr(p2, '\n');
-        email.assign(p2, p3 - p2);
-    }
-
-    p2 = strstr(p1, "\nwebsite=");
-    if (p2) {
-        p2 = p2 + sizeof("\nwebsite=") - 1;
-        p3 = strchr(p2, '\n');
-        website.assign(p2, p3 - p2);
-    }
-
-    p2 = strstr(p1, "\ndate=");
-    if (p2) {
-        p2 = p2 + sizeof("\ndate=") - 1;
-        p3 = strchr(p2, '\n');
-        date.assign(p2, p3 - p2);
-    }
-
-    p2 = strstr(p1, "\ndescription=");
-    if (p2) {
-        p2 = p2 + sizeof("\ndescription=") - 1;
-        p3 = strchr(p2, '\n');
-        description.assign(p2, p3 - p2);
-    }
-
-    p2 = strstr(p1, "\nsametypesequence=");
-    if (p2) {
-        p2 += sizeof("\nsametypesequence=") - 1;
-        p3 = strchr(p2, '\n');
-        sametypesequence.assign(p2, p3 - p2);
-    }
-
-    p2 = strstr(p1, "\nsynwordcount=");
+    SET_IF_EXISTS(author)
+    SET_IF_EXISTS(email)
+    SET_IF_EXISTS(website)
+    SET_IF_EXISTS(date)
+    SET_IF_EXISTS(description)
+    SET_IF_EXISTS(sametypesequence)
     syn_wordcount = 0;
-    if (p2) {
-        p2 += sizeof("\nsynwordcount=") - 1;
-        p3 = strchr(p2, '\n');
-        syn_wordcount = atol(std::string(p2, p3 - p2).c_str());
-    }
-
+    it = key_value_map.find("synwordcount");
+    if (it != key_value_map.end())
+        syn_wordcount = atol(it->second.c_str());
+#undef FIND_KEY
+#undef SET_IF_EXISTS
     return true;
 }
 
@@ -443,14 +429,14 @@ public:
         if (idxfile)
             fclose(idxfile);
     }
-    bool load(const std::string &url, gulong wc, gulong fsize, bool verbose) override;
+    bool load(const std::string &url, gulong wc, off_t fsize, bool verbose) override;
     const gchar *get_key(glong idx) override;
     void get_data(glong idx) override { get_key(idx); }
     const gchar *get_key_and_data(glong idx) override
     {
         return get_key(idx);
     }
-    bool lookup(const char *str, glong &idx) override;
+    bool lookup(const char *str, std::set<glong> &idxs, glong &next_idx) override;
 
 private:
     static const gint ENTR_PER_PAGE = 32;
@@ -503,7 +489,7 @@ public:
     {
     }
     ~WordListIndex() { g_free(idxdatabuf); }
-    bool load(const std::string &url, gulong wc, gulong fsize, bool verbose) override;
+    bool load(const std::string &url, gulong wc, off_t fsize, bool verbose) override;
     const gchar *get_key(glong idx) override { return wordlist[idx]; }
     void get_data(glong idx) override;
     const gchar *get_key_and_data(glong idx) override
@@ -511,7 +497,7 @@ public:
         get_data(idx);
         return get_key(idx);
     }
-    bool lookup(const char *str, glong &idx) override;
+    bool lookup(const char *str, std::set<glong> &idxs, glong &next_idx) override;
 
 private:
     gchar *idxdatabuf;
@@ -629,7 +615,7 @@ bool OffsetIndex::save_cache(const std::string &url, bool verbose)
     return false;
 }
 
-bool OffsetIndex::load(const std::string &url, gulong wc, gulong fsize, bool verbose)
+bool OffsetIndex::load(const std::string &url, gulong wc, off_t fsize, bool verbose)
 {
     wordcount = wc;
     gulong npages = (wc - 1) / ENTR_PER_PAGE + 2;
@@ -698,47 +684,52 @@ const gchar *OffsetIndex::get_key(glong idx)
     return page.entries[idx_in_page].keystr;
 }
 
-bool OffsetIndex::lookup(const char *str, glong &idx)
+bool OffsetIndex::lookup(const char *str, std::set<glong> &idxs, glong &next_idx)
 {
     bool bFound = false;
-    glong iFrom;
-    glong iTo = wordoffset.size() - 2;
-    gint cmpint;
-    glong iThisIndex;
+
     if (stardict_strcmp(str, first.keystr.c_str()) < 0) {
-        idx = 0;
+        next_idx = 0;
         return false;
     } else if (stardict_strcmp(str, real_last.keystr.c_str()) > 0) {
-        idx = INVALID_INDEX;
+        next_idx = INVALID_INDEX;
         return false;
+    }
+
+    // Search for the first page where the word is likely to be located.
+    glong iFrom = 0, iTo = wordoffset.size() - 2;
+    glong iPage = 0, iThisIndex = 0;
+    while (iFrom <= iTo) {
+        iThisIndex = (iFrom + iTo) / 2;
+        glong cmpint = stardict_strcmp(str, get_first_on_page_key(iThisIndex));
+        if (cmpint > 0)
+            iFrom = iThisIndex + 1;
+        else if (cmpint < 0)
+            iTo = iThisIndex - 1;
+        else {
+            bFound = true;
+            break;
+        }
+    }
+
+    if (bFound) {
+        // We can use this found index (even though it might not be the first)
+        // because we will search backwards later and catch any entries on
+        // previous pages.
+        iPage = iThisIndex;
+        iThisIndex = 0; // first item in the page
     } else {
+        iPage = iTo; // prev
+        // Not found at the start of a page, so search within the page that
+        // should contain it. Binary search here is slightly overkill (we're
+        // searching at most ENTR_PER_PAGE = 32 elements) but this way next_idx
+        // is treated the same as other Lookup methods.
+        gulong netr = load_page(iPage);
         iFrom = 0;
-        iThisIndex = 0;
-        while (iFrom <= iTo) {
-            iThisIndex = (iFrom + iTo) / 2;
-            cmpint = stardict_strcmp(str, get_first_on_page_key(iThisIndex));
-            if (cmpint > 0)
-                iFrom = iThisIndex + 1;
-            else if (cmpint < 0)
-                iTo = iThisIndex - 1;
-            else {
-                bFound = true;
-                break;
-            }
-        }
-        if (!bFound)
-            idx = iTo; //prev
-        else
-            idx = iThisIndex;
-    }
-    if (!bFound) {
-        gulong netr = load_page(idx);
-        iFrom = 1; // Needn't search the first word anymore.
         iTo = netr - 1;
-        iThisIndex = 0;
         while (iFrom <= iTo) {
             iThisIndex = (iFrom + iTo) / 2;
-            cmpint = stardict_strcmp(str, page.entries[iThisIndex].keystr);
+            glong cmpint = stardict_strcmp(str, page.entries[iThisIndex].keystr);
             if (cmpint > 0)
                 iFrom = iThisIndex + 1;
             else if (cmpint < 0)
@@ -748,18 +739,26 @@ bool OffsetIndex::lookup(const char *str, glong &idx)
                 break;
             }
         }
-        idx *= ENTR_PER_PAGE;
+    }
+
     if (!bFound)
-            idx += iFrom; //next
-        else
-            idx += iThisIndex;
-    } else {
-        idx *= ENTR_PER_PAGE;
+        next_idx = iPage * ENTR_PER_PAGE + iFrom; // next
+    else {
+        // Convert the found in-page index to the dict index.
+        iThisIndex = iPage * ENTR_PER_PAGE + iThisIndex;
+        // In order to return all idxs that match the search string, walk
+        // linearly behind and ahead of the found index.
+        glong iHeadIndex = iThisIndex - 1; // do not include iThisIndex
+        while (iHeadIndex >= 0 && stardict_strcmp(str, get_key(iHeadIndex)) == 0)
+            idxs.insert(iHeadIndex--);
+        do // no need to double-check iThisIndex -- we know it's a match already
+            idxs.insert(iThisIndex++);
+        while (iThisIndex <= real_last.idx && stardict_strcmp(str, get_key(iThisIndex)) == 0);
     }
     return bFound;
 }
 
-bool WordListIndex::load(const std::string &url, gulong wc, gulong fsize, bool)
+bool WordListIndex::load(const std::string &url, gulong wc, off_t fsize, bool)
 {
     gzFile in = gzopen(url.c_str(), "rb");
     if (in == nullptr)
@@ -772,7 +771,7 @@ bool WordListIndex::load(const std::string &url, gulong wc, gulong fsize, bool)
     if (len < 0)
         return false;
 
-    if (gulong(len) != fsize)
+    if (static_cast<off_t>(len) != fsize)
         return false;
 
     wordlist.resize(wc + 1);
@@ -795,18 +794,18 @@ void WordListIndex::get_data(glong idx)
     wordentry_size = g_ntohl(get_uint32(p1));
 }
 
-bool WordListIndex::lookup(const char *str, glong &idx)
+bool WordListIndex::lookup(const char *str, std::set<glong> &idxs, glong &next_idx)
 {
     bool bFound = false;
-    glong iTo = wordlist.size() - 2;
+    glong iLast = wordlist.size() - 2;
 
     if (stardict_strcmp(str, get_key(0)) < 0) {
-        idx = 0;
-    } else if (stardict_strcmp(str, get_key(iTo)) > 0) {
-        idx = INVALID_INDEX;
+        next_idx = 0;
+    } else if (stardict_strcmp(str, get_key(iLast)) > 0) {
+        next_idx = INVALID_INDEX;
     } else {
         glong iThisIndex = 0;
-        glong iFrom = 0;
+        glong iFrom = 0, iTo = iLast;
         gint cmpint;
         while (iFrom <= iTo) {
             iThisIndex = (iFrom + iTo) / 2;
@@ -821,9 +820,17 @@ bool WordListIndex::lookup(const char *str, glong &idx)
             }
         }
         if (!bFound)
-            idx = iFrom; //next
-        else
-            idx = iThisIndex;
+            next_idx = iFrom; // next
+        else {
+            // In order to return all idxs that match the search string, walk
+            // linearly behind and ahead of the found index.
+            glong iHeadIndex = iThisIndex - 1; // do not include iThisIndex
+            while (iHeadIndex >= 0 && stardict_strcmp(str, get_key(iHeadIndex)) == 0)
+                idxs.insert(iHeadIndex--);
+            do // no need to double-check iThisIndex -- we know it's a match already
+                idxs.insert(iThisIndex++);
+            while (iThisIndex <= iLast && stardict_strcmp(str, get_key(iThisIndex)) == 0);
+        }
     }
     return bFound;
 }
@@ -833,46 +840,87 @@ 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;
     }
 }
 
-bool SynFile::lookup(const char *str, glong &idx)
+bool SynFile::lookup(const char *str, std::set<glong> &idxs, glong &next_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 iLast = synlist.size() - 2;
+    if (iLast < 0)
         return false;
+
+    if (stardict_strcmp(str, get_key(0)) < 0) {
+        next_idx = 0;
+    } else if (stardict_strcmp(str, get_key(iLast)) > 0) {
+        next_idx = INVALID_INDEX;
+    } else {
+        glong iThisIndex = 0;
+        glong iFrom = 0, iTo = iLast;
+        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)
+            next_idx = iFrom; // next
+        else {
+            // In order to return all idxs that match the search string, walk
+            // linearly behind and ahead of the found index.
+            glong iHeadIndex = iThisIndex - 1; // do not include iThisIndex
+            while (iHeadIndex >= 0 && stardict_strcmp(str, get_key(iHeadIndex)) == 0) {
+                const gchar *key = get_key(iHeadIndex--);
+                idxs.insert(g_ntohl(get_uint32(key + strlen(key) + 1)));
+            }
+            do {
+                // no need to double-check iThisIndex -- we know it's a match already
+                const gchar *key = get_key(iThisIndex++);
+                idxs.insert(g_ntohl(get_uint32(key + strlen(key) + 1)));
+            } while (iThisIndex <= iLast && stardict_strcmp(str, get_key(iThisIndex)) == 0);
+        }
+    }
+    return bFound;
 }
 
-bool Dict::Lookup(const char *str, glong &idx)
+bool Dict::Lookup(const char *str, std::set<glong> &idxs, glong &next_idx)
 {
-    return syn_file->lookup(str, idx) || idx_file->lookup(str, idx);
+    bool found = false;
+    found |= syn_file->lookup(str, idxs, next_idx);
+    found |= idx_file->lookup(str, idxs, next_idx);
+    return found;
 }
 
 bool Dict::load(const std::string &ifofilename, bool verbose)
 {
-    gulong idxfilesize;
+    off_t idxfilesize;
     if (!load_ifofile(ifofilename, idxfilesize))
         return false;
 
@@ -916,7 +964,7 @@ bool Dict::load(const std::string &ifofilename, bool verbose)
     return true;
 }
 
-bool Dict::load_ifofile(const std::string &ifofilename, gulong &idxfilesize)
+bool Dict::load_ifofile(const std::string &ifofilename, off_t &idxfilesize)
 {
     DictInfo dict_info;
     if (!dict_info.load_from_ifo_file(ifofilename, false))
@@ -975,120 +1023,8 @@ void Libs::load(const std::list<std::string> &dicts_dirs,
                   });
 }
 
-const gchar *Libs::poGetCurrentWord(glong *iCurrent)
+bool Libs::LookupSimilarWord(const gchar *sWord, std::set<glong> &iWordIndices, int iLib)
 {
-    const gchar *poCurrentWord = nullptr;
-    const gchar *word;
-    for (std::vector<Dict *>::size_type iLib = 0; iLib < oLib.size(); iLib++) {
-        if (iCurrent[iLib] == INVALID_INDEX)
-            continue;
-        if (iCurrent[iLib] >= narticles(iLib) || iCurrent[iLib] < 0)
-            continue;
-        if (poCurrentWord == nullptr) {
-            poCurrentWord = poGetWord(iCurrent[iLib], iLib);
-        } else {
-            word = poGetWord(iCurrent[iLib], iLib);
-
-            if (stardict_strcmp(poCurrentWord, word) > 0)
-                poCurrentWord = word;
-        }
-    }
-    return poCurrentWord;
-}
-
-const gchar *Libs::poGetNextWord(const gchar *sWord, glong *iCurrent)
-{
-    // the input can be:
-    // (word,iCurrent),read word,write iNext to iCurrent,and return next word. used by TopWin::NextCallback();
-    // (nullptr,iCurrent),read iCurrent,write iNext to iCurrent,and return next word. used by AppCore::ListWords();
-    const gchar *poCurrentWord = nullptr;
-    size_t iCurrentLib = 0;
-    const gchar *word;
-
-    for (size_t iLib = 0; iLib < oLib.size(); ++iLib) {
-        if (sWord)
-            oLib[iLib]->Lookup(sWord, iCurrent[iLib]);
-        if (iCurrent[iLib] == INVALID_INDEX)
-            continue;
-        if (iCurrent[iLib] >= narticles(iLib) || iCurrent[iLib] < 0)
-            continue;
-        if (poCurrentWord == nullptr) {
-            poCurrentWord = poGetWord(iCurrent[iLib], iLib);
-            iCurrentLib = iLib;
-        } else {
-            word = poGetWord(iCurrent[iLib], iLib);
-
-            if (stardict_strcmp(poCurrentWord, word) > 0) {
-                poCurrentWord = word;
-                iCurrentLib = iLib;
-            }
-        }
-    }
-    if (poCurrentWord) {
-        iCurrent[iCurrentLib]++;
-        for (std::vector<Dict *>::size_type iLib = 0; iLib < oLib.size(); iLib++) {
-            if (iLib == iCurrentLib)
-                continue;
-            if (iCurrent[iLib] == INVALID_INDEX)
-                continue;
-            if (iCurrent[iLib] >= narticles(iLib) || iCurrent[iLib] < 0)
-                continue;
-            if (strcmp(poCurrentWord, poGetWord(iCurrent[iLib], iLib)) == 0)
-                iCurrent[iLib]++;
-        }
-        poCurrentWord = poGetCurrentWord(iCurrent);
-    }
-    return poCurrentWord;
-}
-
-const gchar *
-Libs::poGetPreWord(glong *iCurrent)
-{
-    // used by TopWin::PreviousCallback(); the iCurrent is cached by AppCore::TopWinWordChange();
-    const gchar *poCurrentWord = nullptr;
-    std::vector<Dict *>::size_type iCurrentLib = 0;
-    const gchar *word;
-
-    for (std::vector<Dict *>::size_type iLib = 0; iLib < oLib.size(); iLib++) {
-        if (iCurrent[iLib] == INVALID_INDEX)
-            iCurrent[iLib] = narticles(iLib);
-        else {
-            if (iCurrent[iLib] > narticles(iLib) || iCurrent[iLib] <= 0)
-                continue;
-        }
-        if (poCurrentWord == nullptr) {
-            poCurrentWord = poGetWord(iCurrent[iLib] - 1, iLib);
-            iCurrentLib = iLib;
-        } else {
-            word = poGetWord(iCurrent[iLib] - 1, iLib);
-            if (stardict_strcmp(poCurrentWord, word) < 0) {
-                poCurrentWord = word;
-                iCurrentLib = iLib;
-            }
-        }
-    }
-
-    if (poCurrentWord) {
-        iCurrent[iCurrentLib]--;
-        for (std::vector<Dict *>::size_type iLib = 0; iLib < oLib.size(); iLib++) {
-            if (iLib == iCurrentLib)
-                continue;
-            if (iCurrent[iLib] > narticles(iLib) || iCurrent[iLib] <= 0)
-                continue;
-            if (strcmp(poCurrentWord, poGetWord(iCurrent[iLib] - 1, iLib)) == 0) {
-                iCurrent[iLib]--;
-            } else {
-                if (iCurrent[iLib] == narticles(iLib))
-                    iCurrent[iLib] = INVALID_INDEX;
-            }
-        }
-    }
-    return poCurrentWord;
-}
-
-bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
-{
-    glong iIndex;
     bool bFound = false;
     gchar *casestr;
 
@@ -1096,7 +1032,7 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
         // to lower case.
         casestr = g_utf8_strdown(sWord, -1);
         if (strcmp(casestr, sWord)) {
-            if (oLib[iLib]->Lookup(casestr, iIndex))
+            if (oLib[iLib]->Lookup(casestr, iWordIndices))
                 bFound = true;
         }
         g_free(casestr);
@@ -1104,7 +1040,7 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
         if (!bFound) {
             casestr = g_utf8_strup(sWord, -1);
             if (strcmp(casestr, sWord)) {
-                if (oLib[iLib]->Lookup(casestr, iIndex))
+                if (oLib[iLib]->Lookup(casestr, iWordIndices))
                     bFound = true;
             }
             g_free(casestr);
@@ -1118,7 +1054,7 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
             g_free(firstchar);
             g_free(nextchar);
             if (strcmp(casestr, sWord)) {
-                if (oLib[iLib]->Lookup(casestr, iIndex))
+                if (oLib[iLib]->Lookup(casestr, iWordIndices))
                     bFound = true;
             }
             g_free(casestr);
@@ -1138,12 +1074,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
             if (isupcase || sWord[iWordLen - 1] == 's' || !strncmp(&sWord[iWordLen - 2], "ed", 2)) {
                 strcpy(sNewWord, sWord);
                 sNewWord[iWordLen - 1] = '\0'; // cut "s" or "d"
-                if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                     bFound = true;
                 else if (isupcase || g_ascii_isupper(sWord[0])) {
                     casestr = g_ascii_strdown(sNewWord, -1);
                     if (strcmp(casestr, sNewWord)) {
-                        if (oLib[iLib]->Lookup(casestr, iIndex))
+                        if (oLib[iLib]->Lookup(casestr, iWordIndices))
                             bFound = true;
                     }
                     g_free(casestr);
@@ -1161,13 +1097,13 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                     && !bIsVowel(sNewWord[iWordLen - 4]) && bIsVowel(sNewWord[iWordLen - 5])) { // doubled
 
                     sNewWord[iWordLen - 3] = '\0';
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else {
                         if (isupcase || g_ascii_isupper(sWord[0])) {
                             casestr = g_ascii_strdown(sNewWord, -1);
                             if (strcmp(casestr, sNewWord)) {
-                                if (oLib[iLib]->Lookup(casestr, iIndex))
+                                if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                     bFound = true;
                             }
                             g_free(casestr);
@@ -1177,12 +1113,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                     }
                 }
                 if (!bFound) {
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else if (isupcase || g_ascii_isupper(sWord[0])) {
                         casestr = g_ascii_strdown(sNewWord, -1);
                         if (strcmp(casestr, sNewWord)) {
-                            if (oLib[iLib]->Lookup(casestr, iIndex))
+                            if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                 bFound = true;
                         }
                         g_free(casestr);
@@ -1200,13 +1136,13 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                 if (iWordLen > 6 && (sNewWord[iWordLen - 4] == sNewWord[iWordLen - 5])
                     && !bIsVowel(sNewWord[iWordLen - 5]) && bIsVowel(sNewWord[iWordLen - 6])) { // doubled
                     sNewWord[iWordLen - 4] = '\0';
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else {
                         if (isupcase || g_ascii_isupper(sWord[0])) {
                             casestr = g_ascii_strdown(sNewWord, -1);
                             if (strcmp(casestr, sNewWord)) {
-                                if (oLib[iLib]->Lookup(casestr, iIndex))
+                                if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                     bFound = true;
                             }
                             g_free(casestr);
@@ -1216,12 +1152,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                     }
                 }
                 if (!bFound) {
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else if (isupcase || g_ascii_isupper(sWord[0])) {
                         casestr = g_ascii_strdown(sNewWord, -1);
                         if (strcmp(casestr, sNewWord)) {
-                            if (oLib[iLib]->Lookup(casestr, iIndex))
+                            if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                 bFound = true;
                         }
                         g_free(casestr);
@@ -1232,12 +1168,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                         strcat(sNewWord, "E"); // add a char "E"
                     else
                         strcat(sNewWord, "e"); // add a char "e"
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else if (isupcase || g_ascii_isupper(sWord[0])) {
                         casestr = g_ascii_strdown(sNewWord, -1);
                         if (strcmp(casestr, sNewWord)) {
-                            if (oLib[iLib]->Lookup(casestr, iIndex))
+                            if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                 bFound = true;
                         }
                         g_free(casestr);
@@ -1252,12 +1188,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
             if (isupcase || (!strncmp(&sWord[iWordLen - 2], "es", 2) && (sWord[iWordLen - 3] == 's' || sWord[iWordLen - 3] == 'x' || sWord[iWordLen - 3] == 'o' || (iWordLen > 4 && sWord[iWordLen - 3] == 'h' && (sWord[iWordLen - 4] == 'c' || sWord[iWordLen - 4] == 's'))))) {
                 strcpy(sNewWord, sWord);
                 sNewWord[iWordLen - 2] = '\0';
-                if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                     bFound = true;
                 else if (isupcase || g_ascii_isupper(sWord[0])) {
                     casestr = g_ascii_strdown(sNewWord, -1);
                     if (strcmp(casestr, sNewWord)) {
-                        if (oLib[iLib]->Lookup(casestr, iIndex))
+                        if (oLib[iLib]->Lookup(casestr, iWordIndices))
                             bFound = true;
                     }
                     g_free(casestr);
@@ -1274,13 +1210,13 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                 if (iWordLen > 5 && (sNewWord[iWordLen - 3] == sNewWord[iWordLen - 4])
                     && !bIsVowel(sNewWord[iWordLen - 4]) && bIsVowel(sNewWord[iWordLen - 5])) { // doubled
                     sNewWord[iWordLen - 3] = '\0';
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else {
                         if (isupcase || g_ascii_isupper(sWord[0])) {
                             casestr = g_ascii_strdown(sNewWord, -1);
                             if (strcmp(casestr, sNewWord)) {
-                                if (oLib[iLib]->Lookup(casestr, iIndex))
+                                if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                     bFound = true;
                             }
                             g_free(casestr);
@@ -1290,12 +1226,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                     }
                 }
                 if (!bFound) {
-                    if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                    if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                         bFound = true;
                     else if (isupcase || g_ascii_isupper(sWord[0])) {
                         casestr = g_ascii_strdown(sNewWord, -1);
                         if (strcmp(casestr, sNewWord)) {
-                            if (oLib[iLib]->Lookup(casestr, iIndex))
+                            if (oLib[iLib]->Lookup(casestr, iWordIndices))
                                 bFound = true;
                         }
                         g_free(casestr);
@@ -1314,12 +1250,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                     strcat(sNewWord, "Y"); // add a char "Y"
                 else
                     strcat(sNewWord, "y"); // add a char "y"
-                if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                     bFound = true;
                 else if (isupcase || g_ascii_isupper(sWord[0])) {
                     casestr = g_ascii_strdown(sNewWord, -1);
                     if (strcmp(casestr, sNewWord)) {
-                        if (oLib[iLib]->Lookup(casestr, iIndex))
+                        if (oLib[iLib]->Lookup(casestr, iWordIndices))
                             bFound = true;
                     }
                     g_free(casestr);
@@ -1337,12 +1273,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
                     strcat(sNewWord, "Y"); // add a char "Y"
                 else
                     strcat(sNewWord, "y"); // add a char "y"
-                if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                     bFound = true;
                 else if (isupcase || g_ascii_isupper(sWord[0])) {
                     casestr = g_ascii_strdown(sNewWord, -1);
                     if (strcmp(casestr, sNewWord)) {
-                        if (oLib[iLib]->Lookup(casestr, iIndex))
+                        if (oLib[iLib]->Lookup(casestr, iWordIndices))
                             bFound = true;
                     }
                     g_free(casestr);
@@ -1356,12 +1292,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
             if (isupcase || (!strncmp(&sWord[iWordLen - 2], "er", 2))) {
                 strcpy(sNewWord, sWord);
                 sNewWord[iWordLen - 2] = '\0';
-                if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                     bFound = true;
                 else if (isupcase || g_ascii_isupper(sWord[0])) {
                     casestr = g_ascii_strdown(sNewWord, -1);
                     if (strcmp(casestr, sNewWord)) {
-                        if (oLib[iLib]->Lookup(casestr, iIndex))
+                        if (oLib[iLib]->Lookup(casestr, iWordIndices))
                             bFound = true;
                     }
                     g_free(casestr);
@@ -1375,12 +1311,12 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
             if (isupcase || (!strncmp(&sWord[iWordLen - 3], "est", 3))) {
                 strcpy(sNewWord, sWord);
                 sNewWord[iWordLen - 3] = '\0';
-                if (oLib[iLib]->Lookup(sNewWord, iIndex))
+                if (oLib[iLib]->Lookup(sNewWord, iWordIndices))
                     bFound = true;
                 else if (isupcase || g_ascii_isupper(sWord[0])) {
                     casestr = g_ascii_strdown(sNewWord, -1);
                     if (strcmp(casestr, sNewWord)) {
-                        if (oLib[iLib]->Lookup(casestr, iIndex))
+                        if (oLib[iLib]->Lookup(casestr, iWordIndices))
                             bFound = true;
                     }
                     g_free(casestr);
@@ -1390,9 +1326,6 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
 
         g_free(sNewWord);
     }
-
-    if (bFound)
-        iWordIndex = iIndex;
 #if 0
     else {
         //don't change iWordIndex here.
@@ -1403,11 +1336,11 @@ bool Libs::LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib)
     return bFound;
 }
 
-bool Libs::SimpleLookupWord(const gchar *sWord, glong &iWordIndex, int iLib)
+bool Libs::SimpleLookupWord(const gchar *sWord, std::set<glong> &iWordIndices, int iLib)
 {
-    bool bFound = oLib[iLib]->Lookup(sWord, iWordIndex);
+    bool bFound = oLib[iLib]->Lookup(sWord, iWordIndices);
     if (!bFound && fuzzy_)
-        bFound = LookupSimilarWord(sWord, iWordIndex, iLib);
+        bFound = LookupSimilarWord(sWord, iWordIndices, iLib);
     return bFound;
 }
 

src/stardict_lib.hpp

@@ -1,11 +1,10 @@
 #pragma once
 
-#include <cstdio>
 #include <cstring>
 #include <functional>
 #include <list>
-#include <map>
 #include <memory>
+#include <set>
 #include <string>
 #include <vector>
 
@@ -78,8 +77,8 @@ struct DictInfo {
     std::string website;
     std::string date;
     std::string description;
-    guint32 index_file_size;
-    guint32 syn_file_size;
+    off_t index_file_size;
+    off_t syn_file_size;
     std::string sametypesequence;
 
     bool load_from_ifo_file(const std::string &ifofilename, bool istreedict);
@@ -92,21 +91,31 @@ public:
     guint32 wordentry_size;
 
     virtual ~IIndexFile() {}
-    virtual bool load(const std::string &url, gulong wc, gulong fsize, bool verbose) = 0;
+    virtual bool load(const std::string &url, gulong wc, off_t fsize, bool verbose) = 0;
     virtual const gchar *get_key(glong idx) = 0;
     virtual void get_data(glong idx) = 0;
     virtual const gchar *get_key_and_data(glong idx) = 0;
-    virtual bool lookup(const char *str, glong &idx) = 0;
+    virtual bool lookup(const char *str, std::set<glong> &idxs, glong &next_idx) = 0;
+    virtual bool lookup(const char *str, std::set<glong> &idxs)
+    {
+        glong unused_next_idx;
+        return lookup(str, idxs, unused_next_idx);
+    };
 };
 
 class SynFile
 {
 public:
+    SynFile() {}
+    ~SynFile() {}
     bool load(const std::string &url, gulong wc);
-    bool lookup(const char *str, glong &idx);
+    bool lookup(const char *str, std::set<glong> &idxs, glong &next_idx);
+    bool lookup(const char *str, std::set<glong> &idxs);
+    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
@@ -133,7 +142,12 @@ public:
         *offset = idx_file->wordentry_offset;
         *size = idx_file->wordentry_size;
     }
-    bool Lookup(const char *str, glong &idx);
+    bool Lookup(const char *str, std::set<glong> &idxs, glong &next_idx);
+    bool Lookup(const char *str, std::set<glong> &idxs)
+    {
+        glong unused_next_idx;
+        return Lookup(str, idxs, unused_next_idx);
+    }
 
     bool LookupWithRule(GPatternSpec *pspec, glong *aIndex, int iBuffLen);
 
@@ -146,7 +160,7 @@ private:
     std::unique_ptr<IIndexFile> idx_file;
     std::unique_ptr<SynFile> syn_file;
 
-    bool load_ifofile(const std::string &ifofilename, gulong &idxfilesize);
+    bool load_ifofile(const std::string &ifofilename, off_t &idxfilesize);
 };
 
 class Libs
@@ -181,15 +195,12 @@ public:
             return nullptr;
         return oLib[iLib]->get_data(iIndex);
     }
-    const gchar *poGetCurrentWord(glong *iCurrent);
-    const gchar *poGetNextWord(const gchar *word, glong *iCurrent);
-    const gchar *poGetPreWord(glong *iCurrent);
-    bool LookupWord(const gchar *sWord, glong &iWordIndex, int iLib)
+    bool LookupWord(const gchar *sWord, std::set<glong> &iWordIndices, int iLib)
     {
-        return oLib[iLib]->Lookup(sWord, iWordIndex);
+        return oLib[iLib]->Lookup(sWord, iWordIndices);
     }
-    bool LookupSimilarWord(const gchar *sWord, glong &iWordIndex, int iLib);
-    bool SimpleLookupWord(const gchar *sWord, glong &iWordIndex, int iLib);
+    bool LookupSimilarWord(const gchar *sWord, std::set<glong> &iWordIndices, int iLib);
+    bool SimpleLookupWord(const gchar *sWord, std::set<glong> &iWordIndices, int iLib);
 
     bool LookupWithFuzzy(const gchar *sWord, gchar *reslist[], gint reslist_size);
     gint LookupWithRule(const gchar *sWord, gchar *reslist[]);

tests/not-unix-newlines-ifo/russian/russian.ifo

@@ -0,0 +1,9 @@
+StarDict's dict ifo file
+version=3.0.0
+bookname=Russian-English Dictionary (ru-en)
+wordcount=415144
+idxfilesize=12344255
+sametypesequence=h
+synwordcount=1277580
+author=Vuizur
+description=

tests/stardict-test_multiple_results-2.4.2/test.ifo

@@ -0,0 +1,7 @@
+StarDict's dict ifo file
+version=3.0.0
+bookname=Test multiple results
+wordcount=246
+idxfilesize=5977
+synwordcount=124
+description=

tests/t_json

@@ -18,8 +18,15 @@ test_json() {
     fi
 }
 
-test_json '[{"name": "Test synonyms", "wordcount": "2"},{"name": "Sample 1 test dictionary", "wordcount": "1"},{"name": "test_dict", "wordcount": "1"}]' -x -j -l -n --data-dir "$TEST_DIR"
+test_json '[{"name": "Russian-English Dictionary (ru-en)", "wordcount": "415144"},
+            {"name": "Test synonyms", "wordcount": "2"},
+            {"name": "Test multiple results", "wordcount": "246"},
+            {"name": "Sample 1 test dictionary", "wordcount": "1"},
+            {"name": "test_dict", "wordcount": "1"}]' -x -j -l -n --data-dir "$TEST_DIR"
 test_json '[{"dict": "Test synonyms","word":"test","definition":"\u000aresult of test"}]' -x -j -n --data-dir "$TEST_DIR" foo
 test_json '[]' -x -j -n --data-dir "$TEST_DIR" foobarbaaz
 
+# Test multiple searches, with the first failing.
+test_json '[][{"dict": "Test synonyms","word":"test","definition":"\u000aresult of test"}]' -x -j -n --data-dir "$TEST_DIR" foobarbaaz foo
+
 exit 0

tests/t_multiple_results

@@ -0,0 +1,67 @@
+#!/bin/sh
+
+set -e
+
+SDCV="$1"
+TEST_DIR="$2"
+
+unset SDCV_PAGER
+unset STARDICT_DATA_DIR
+
+test_json() {
+    word="$1"
+    jq_cmp="$2"
+    result="$("$SDCV" --data-dir "$TEST_DIR" -exjn "$word" | sed 's|\\n|\\u000a|g')"
+    cmp_result="$(echo "$result" | jq "$jq_cmp")"
+    if [ "$cmp_result" != "true" ]; then
+        echo "expected '$jq_cmp' to return true, but $result didn't"
+        exit 1
+    fi
+}
+
+# Basic two-result search for the same headword.
+test_json bark \
+    '. == [
+        {"dict":"Test multiple results","word":"bark","definition":"\u000aThe harsh sound made by a dog."},
+        {"dict":"Test multiple results","word":"bark","definition":"\u000aThe tough outer covering of trees and other woody plants."}
+    ]'
+
+# Multi-result search where one word exists as both a synyonym and a separate
+# headword. This ensures that if there is a matching synyonym we don't skip the
+# regular search.
+test_json cat \
+    '. == [
+        {"dict":"Test multiple results","word":"cat","definition":"\u000aA cute animal which (rarely) barks."},
+        {"dict":"Test multiple results","word":"lion","definition":"\u000aA larger cat which might bite your head off."},
+        {"dict":"Test multiple results","word":"panther","definition":"\u000aI know very little about panthers, sorry."}
+    ]'
+
+# Many-result search for a word that matches 120 distinct headwords.
+test_json many_headwords 'length == 120'
+test_json many_headwords 'all(.word == "many_headwords")'
+test_json many_headwords \
+    'to_entries | map(.value.definition == "\u000aDefinition for [many_headwords] entry #\(.key+1) (same headword).") | all'
+
+# Many-result search for 120 words that have the same synonym.
+test_json many_synonyms 'length == 120'
+test_json many_synonyms \
+    'to_entries | map(.value.word == "many_synonyms-\(.key+101)") | all'
+test_json many_synonyms \
+    'to_entries | map(.value.definition == "\u000aDefinition for [many_synonyms-\(.key+101)] (same synonym).") | all'
+
+# Ensure that we don't return more than one result even if a word can be
+# resolved in more than one way.
+#
+# Most well-formed dictionaries don't have entries like this (it basically
+# requires you to have a dictionary where there is a synonym that is identical
+# to a word's headword or multiple identical synyonym entries).
+#
+# This entry was created by creating extra synonyms with different names then
+# modifying the .syn file manually.
+test_json many_resolution_paths \
+    '. == [
+        {"dict":"Test multiple results","word":"many_resolution_paths",
+         "definition":"\u000aDefinition for [many_resolution_paths] headword (same word, multiple synonym entries)."}
+    ]'
+
+exit 0

tests/t_newlines_in_ifo

@@ -0,0 +1,18 @@
+#!/bin/sh
+
+set -e
+
+PATH_TO_SDCV="$1"
+TEST_DIR="$2"
+
+unset SDCV_PAGER
+unset STARDICT_DATA_DIR
+
+RES=$("$PATH_TO_SDCV" -n -x --data-dir="$TEST_DIR/not-unix-newlines-ifo" -l | tail -n 1)
+
+if [ "$RES" = "Russian-English Dictionary (ru-en)    415144" ]; then
+  exit 0
+else
+  echo "test failed, unexpected result: $RES" >&2
+  exit 1
+fi