drop symbol name lookup code

Author: darealshinji

src/data_external.cpp

@@ -136,17 +136,17 @@ void gendlopen::load_template(templates::name file)
     switch (file)
     {
         /* never add line directive to license part */
-        CASE_X(license,         "license.h", false);
+        CASE_X(license,         "license.h",         false);
         CASE_X(filename_macros, "filename_macros.h", b);
-        CASE_X(common_header,   "common.h", b);
-        CASE_X(c_header,        "c.h", b);
-        CASE_X(c_body,          "c.c", b);
-        CASE_X(cxx_header,      "cxx.hpp", b);
-        CASE_X(cxx_body,        "cxx.cpp", b);
-        CASE_X(min_c_header,    "minimal.h", b);
+        CASE_X(common_header,   "common.h",          b);
+        CASE_X(c_header,        "c.h",               b);
+        CASE_X(c_body,          "c.c",               b);
+        CASE_X(cxx_header,      "cxx.hpp",           b);
+        CASE_X(cxx_body,        "cxx.cpp",           b);
+        CASE_X(min_c_header,    "minimal.h",         b);
         CASE_X(min_cxx_header,  "minimal_cxxeh.hpp", b);
-        CASE_X(plugin_header,   "plugin.h", b);
-        CASE_X(plugin_body,     "plugin.c", b);
+        CASE_X(plugin_header,   "plugin.h",          b);
+        CASE_X(plugin_body,     "plugin.c",          b);
     }
 }
 

src/gendlopen.cpp

@@ -249,8 +249,6 @@ void gendlopen::process(const int &argc, char ** const &argv)
 
     if (print_symbols()) {
         print_symbols_to_stdout(m_typedefs, m_prototypes, m_objects);
-    } else if (print_lookup()) {
-        save::symbol_name_lookup(m_pfx_upper, m_prototypes, m_objects);
     } else if (!custom_template().empty()) {
         process_custom_template();
     } else {

src/gendlopen.hpp

@@ -49,9 +49,6 @@ namespace save
 
     /* open output file stream for writing */
     void open_ofstream(const std::filesystem::path &opath, bool force);
-
-    /* creates the GDO_CHECK_SYMBOL_NAME() macro and saves it to save::ofs */
-    size_t symbol_name_lookup(const std::string &pfx_upper, const vproto_t &v_prototypes, const vproto_t &v_objects);
 }
 
 
@@ -150,22 +147,21 @@ class gendlopen
     /* get() / set() an option */
 
     /*   type            method name      default value */
-    OPT( std::string,    input,           {}           )
-    OPT( std::string,    output,          "-"          )
-    OPT( output::format, format,          output::c    )
-    OPT( param::names,   parameter_names, param::read  )
-    OPT( std::string,    custom_template, {}           )
+    OPT( std::string,    input,           {}          )
+    OPT( std::string,    output,          "-"         )
+    OPT( output::format, format,          output::c   )
+    OPT( param::names,   parameter_names, param::read )
+    OPT( std::string,    custom_template, {}          )
     OPT( std::string,    templates_path,  DEFAULT_TEMPLATES_PATH )
-    OPT( std::string,    default_lib,     {}           )
-    OPT( bool,           force,           false        )
-    OPT( bool,           separate,        false        )
-    OPT( bool,           ast_all_symbols, false        )
-    OPT( bool,           print_symbols,   false        )
-    OPT( bool,           print_lookup,    false        )
-    OPT( bool,           read_options,    true         )
-    OPT( bool,           print_date,      true         )
-    OPT( bool,           line_directive,  false        )
-    OPT( bool,           pragma_once,     true         )
+    OPT( std::string,    default_lib,     {}          )
+    OPT( bool,           force,           false       )
+    OPT( bool,           separate,        false       )
+    OPT( bool,           ast_all_symbols, false       )
+    OPT( bool,           print_symbols,   false       )
+    OPT( bool,           read_options,    true        )
+    OPT( bool,           print_date,      true        )
+    OPT( bool,           line_directive,  false       )
+    OPT( bool,           pragma_once,     true        )
 
     void add_pfx(const std::string &s) { m_prefix_list.push_back(s); }
     void add_sym(const std::string &s) { m_symbol_list.push_back(s); }

src/generate.cpp

@@ -117,6 +117,62 @@ namespace /* anonymous */
 
 #endif /* __MINGW32__ */
 
+
+    /**
+    * Look for a common symbol prefix.
+    * Many APIs share a common prefix among their symbols.
+    * If you want to load a specific symbol we can use this
+    * later for a faster lookup.
+    */
+    std::string get_common_prefix(vproto_t &v_prototypes, vproto_t &v_objects)
+    {
+        vstring_t vec;
+        size_t n;
+
+        /* copy symbol names */
+        for (const auto &e : v_prototypes) {
+            vec.push_back(e.symbol);
+        }
+
+        for (const auto &e : v_objects) {
+            vec.push_back(e.symbol);
+        }
+
+        /* need at least 2 symbols */
+        if (vec.size() < 2) {
+            return {};
+        }
+
+        /* get shortest symbol length */
+        size_t shortest_sym_len = vec.front().size();
+
+        /* skip first entry */
+        for (auto it = vec.begin() + 1; it != vec.end(); it++) {
+            /* prevent `min()' macro expansion from Windows headers */
+            shortest_sym_len = std::min<size_t>(shortest_sym_len, (*it).size());
+        }
+
+        /* compare each letter of every entry */
+        for (n = 0; n < shortest_sym_len; n++) {
+            /* skip first entry */
+            for (auto it = vec.begin() + 1; it != vec.end(); it++) {
+                if ((*it).empty()) {
+                    return {};
+                }
+
+                /* compare against first entry */
+                if ((*it).at(n) != vec.front().at(n)) {
+                    /* common prefix found (can be empty) */
+                    return vec.at(0).substr(0, n);
+                }
+            }
+        }
+
+        /* shortest symbol name equals prefix, i.e. if a symbol `foo'
+         * and `foobar' exist the prefix is `foo' */
+        return vec.at(0).substr(0, n);
+    }
+
 } /* end anonymous namespace */
 
 
@@ -409,16 +465,6 @@ void gendlopen::generate()
     bool is_cxx = false;
     size_t lines = 0;
 
-    /* whether to generate a symbol lookup macro and
-     * where to save it */
-    enum {
-        GEN_MACRO_NONE,
-        GEN_MACRO_HEADER,
-        GEN_MACRO_BODY
-    };
-
-    int gen_macro = GEN_MACRO_NONE;
-
     /************* lambda functions *************/
 
     auto lf_print_lineno = [&, this] () {
@@ -465,11 +511,6 @@ void gendlopen::generate()
         lines += save::extra_defines(m_defines);
         lines += save::includes(m_includes, is_cxx);
         lines += save::typedefs(m_typedefs);
-
-        /* save macro in header */
-        if (gen_macro == GEN_MACRO_HEADER) {
-            lines += save::symbol_name_lookup(m_pfx_upper, m_prototypes, m_objects);
-        }
     };
 
     auto lf_header_template_data = [&] () {
@@ -488,11 +529,6 @@ void gendlopen::generate()
         save::ofs << "#define " << m_pfx_upper << "_INCLUDED_IN_BODY\n";
         save::ofs << "#include \"" << header_name << "\"\n";
         save::ofs << '\n';
-
-        /* save macro in body */
-        if (gen_macro == GEN_MACRO_BODY) {
-            save::symbol_name_lookup(m_pfx_upper, m_prototypes, m_objects);
-        }
     };
 
     auto lf_body_template_data = [&] () {
@@ -516,11 +552,10 @@ void gendlopen::generate()
     switch (m_format)
     {
     case output::c:
-        gen_macro = m_separate ? GEN_MACRO_BODY : GEN_MACRO_HEADER;
+    case output::plugin:
         break;
 
     case output::cxx:
-        gen_macro = GEN_MACRO_HEADER;
         is_cxx = true;
         break;
 
@@ -533,9 +568,6 @@ void gendlopen::generate()
         is_cxx = true;
         break;
 
-    case output::plugin:
-        break;
-
     [[unlikely]] case output::error:
         throw error(std::string(__func__) + ": m_format == output::error");
     }
@@ -567,6 +599,10 @@ void gendlopen::generate()
         m_defines += "#define " + m_pfx_upper + "_HARDCODED_DEFAULT_LIBW " + lib_w + '\n';
     }
 
+    /* common symbol prefix (can be empty) */
+    m_defines += "#define " + m_pfx_upper + "_COMMON_PREFIX "
+        "\"" + get_common_prefix(m_prototypes, m_objects) + "\"\n";
+
     /* create template data */
     create_template_lists(header_data, body_data);
 

src/help.cpp

@@ -88,7 +88,6 @@ namespace help
             "                    modes are: read (default), skip, create\n"
             "  -ast-all-symbols  use all symbols from a Clang AST (`-P' and `-S' are ignored)\n"
             "  -print-symbols    print list of found symbols and exit\n"
-            "  -print-lookup     print a C lookup code macro generated from the found symbols and exit\n"
             "  -ignore-options   ignore `%option' lines from input file\n"
             "  -no-date          don't show current date in output\n"
             "  -no-pragma-once   use `#ifndef' header guard instead of `#pragma once'\n"
@@ -310,11 +309,6 @@ namespace help
             "\n"
 
 
-            "  -print-lookup\n"
-            "    Print a C lookup code macro generated from the found symbols and exit.\n"
-            "\n"
-
-
             "  -ignore-options\n"
             "    Ignore lines beginning with `%option' from the input file.\n"
             "\n"

src/meson.build

@@ -16,7 +16,6 @@ gendlopen_src = files(
     'parameter_names.cpp',
     'parse.cpp',
     'substitute.cpp',
-    'symbol_name_lookup.cpp',
     'tokenize.cpp',
     'utils.cpp'
 )

src/options.cpp

@@ -226,9 +226,6 @@ void gendlopen::parse_cmdline(const int &argc, char ** const &argv)
             } else if (a.get_noarg("print-symbols")) {
                 print_symbols(true);
                 continue;
-            } else if (a.get_noarg("print-lookup")) {
-                print_lookup(true);
-                continue;
             }
             break;