notepad-plus-plus/lexilla/access/LexillaAccess.cxx

286 lines
7.6 KiB
C++

// SciTE - Scintilla based Text Editor
/** @file LexillaAccess.cxx
** Interface to loadable lexers.
** Maintains a list of lexer library paths and CreateLexer functions.
** If list changes then load all the lexer libraries and find the functions.
** When asked to create a lexer, call each function until one succeeds.
**/
// Copyright 2019 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.
#include <cstring>
#include <string>
#include <string_view>
#include <vector>
#include <set>
#if !_WIN32
#include <dlfcn.h>
#else
#include <windows.h>
#endif
#include "ILexer.h"
#include "Lexilla.h"
#include "LexillaAccess.h"
namespace {
#if _WIN32
typedef FARPROC Function;
typedef HMODULE Module;
constexpr const char *pathSeparator = "\\";
#else
typedef void *Function;
typedef void *Module;
constexpr const char *pathSeparator = "/";
#endif
/// Generic function to convert from a Function(void* or FARPROC) to a function pointer.
/// This avoids undefined and conditionally defined behaviour.
template<typename T>
T FunctionPointer(Function function) noexcept {
static_assert(sizeof(T) == sizeof(function));
T fp {};
memcpy(&fp, &function, sizeof(T));
return fp;
}
#if _WIN32
std::wstring WideStringFromUTF8(std::string_view sv) {
const int sLength = static_cast<int>(sv.length());
const int cchWide = ::MultiByteToWideChar(CP_UTF8, 0, sv.data(), sLength, nullptr, 0);
std::wstring sWide(cchWide, 0);
::MultiByteToWideChar(CP_UTF8, 0, sv.data(), sLength, sWide.data(), cchWide);
return sWide;
}
#endif
// Turn off deprecation checks as LexillaAccess deprecates its wrapper over
// the deprecated LexerNameFromID. Thus use within LexillaAccess is intentional.
#if defined(__GNUC__) || defined(__clang__)
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
#else
#pragma warning(disable: 4996)
#endif
std::string directoryLoadDefault;
std::string lastLoaded;
struct LexLibrary {
Lexilla::CreateLexerFn fnCL;
Lexilla::LexerNameFromIDFn fnLNFI;
Lexilla::GetLibraryPropertyNamesFn fnGLPN;
Lexilla::SetLibraryPropertyFn fnSLP;
std::string nameSpace;
};
std::vector<LexLibrary> libraries;
std::vector<std::string> lexers;
std::vector<std::string> libraryProperties;
Function FindSymbol(Module m, const char *symbol) noexcept {
#if _WIN32
return ::GetProcAddress(m, symbol);
#else
return dlsym(m, symbol);
#endif
}
Lexilla::CreateLexerFn pCreateLexerDefault = nullptr;
bool NameContainsDot(std::string_view path) noexcept {
for (std::string_view::const_reverse_iterator it = path.crbegin();
it != path.crend(); ++it) {
if (*it == '.')
return true;
if (*it == '/' || *it == '\\')
return false;
}
return false;
}
constexpr bool HasPrefix(std::string_view s, std::string_view prefix) noexcept {
return (s.size() >= prefix.size()) && (prefix == s.substr(0, prefix.size()));
}
}
void Lexilla::SetDefault(CreateLexerFn pCreate) noexcept {
pCreateLexerDefault = pCreate;
}
void Lexilla::SetDefaultDirectory(std::string_view directory) {
directoryLoadDefault = directory;
}
bool Lexilla::Load(std::string_view sharedLibraryPaths) {
if (sharedLibraryPaths == lastLoaded) {
return !libraries.empty();
}
std::string_view paths = sharedLibraryPaths;
lexers.clear();
libraries.clear();
while (!paths.empty()) {
const size_t separator = paths.find_first_of(';');
std::string path(paths.substr(0, separator));
if (separator == std::string::npos) {
paths.remove_prefix(paths.size());
} else {
paths.remove_prefix(separator + 1);
}
if (path == ".") {
if (directoryLoadDefault.empty()) {
path = "";
} else {
path = directoryLoadDefault;
path += pathSeparator;
}
path += LEXILLA_LIB;
}
if (!NameContainsDot(path)) {
// No '.' in name so add extension
path.append(LEXILLA_EXTENSION);
}
#if _WIN32
// Convert from UTF-8 to wide characters
std::wstring wsPath = WideStringFromUTF8(path);
Module lexillaDL = ::LoadLibraryW(wsPath.c_str());
#else
Module lexillaDL = dlopen(path.c_str(), RTLD_LAZY);
#endif
if (lexillaDL) {
GetLexerCountFn fnLexerCount = FunctionPointer<GetLexerCountFn>(
FindSymbol(lexillaDL, LEXILLA_GETLEXERCOUNT));
GetLexerNameFn fnLexerName = FunctionPointer<GetLexerNameFn>(
FindSymbol(lexillaDL, LEXILLA_GETLEXERNAME));
if (fnLexerCount && fnLexerName) {
const int nLexers = fnLexerCount();
for (int i = 0; i < nLexers; i++) {
char name[100] = "";
fnLexerName(i, name, sizeof(name));
lexers.push_back(name);
}
}
CreateLexerFn fnCL = FunctionPointer<CreateLexerFn>(
FindSymbol(lexillaDL, LEXILLA_CREATELEXER));
LexerNameFromIDFn fnLNFI = FunctionPointer<LexerNameFromIDFn>(
FindSymbol(lexillaDL, LEXILLA_LEXERNAMEFROMID));
GetLibraryPropertyNamesFn fnGLPN = FunctionPointer<GetLibraryPropertyNamesFn>(
FindSymbol(lexillaDL, LEXILLA_GETLIBRARYPROPERTYNAMES));
SetLibraryPropertyFn fnSLP = FunctionPointer<SetLibraryPropertyFn>(
FindSymbol(lexillaDL, LEXILLA_SETLIBRARYPROPERTY));
GetNameSpaceFn fnGNS = FunctionPointer<GetNameSpaceFn>(
FindSymbol(lexillaDL, LEXILLA_GETNAMESPACE));
std::string nameSpace;
if (fnGNS) {
nameSpace = fnGNS();
nameSpace += LEXILLA_NAMESPACE_SEPARATOR;
}
LexLibrary lexLib {
fnCL,
fnLNFI,
fnGLPN,
fnSLP,
nameSpace
};
libraries.push_back(lexLib);
}
}
lastLoaded = sharedLibraryPaths;
std::set<std::string> nameSet;
for (const LexLibrary &lexLib : libraries) {
if (lexLib.fnGLPN) {
const char *cpNames = lexLib.fnGLPN();
if (cpNames) {
std::string_view names = cpNames;
while (!names.empty()) {
const size_t separator = names.find_first_of('\n');
std::string name(names.substr(0, separator));
nameSet.insert(name);
if (separator == std::string::npos) {
names.remove_prefix(names.size());
} else {
names.remove_prefix(separator + 1);
}
}
}
}
}
// Standard Lexilla does not have any properties so can't be added to set.
libraryProperties = std::vector<std::string>(nameSet.begin(), nameSet.end());
return !libraries.empty();
}
Scintilla::ILexer5 *Lexilla::MakeLexer(std::string_view languageName) {
std::string sLanguageName(languageName); // Ensure NUL-termination
// First, try to match namespace then name suffix
for (const LexLibrary &lexLib : libraries) {
if (lexLib.fnCL && !lexLib.nameSpace.empty()) {
if (HasPrefix(languageName, lexLib.nameSpace)) {
Scintilla::ILexer5 *pLexer = lexLib.fnCL(sLanguageName.substr(lexLib.nameSpace.size()).c_str());
if (pLexer) {
return pLexer;
}
}
}
}
// If no match with namespace, try to just match name
for (const LexLibrary &lexLib : libraries) {
if (lexLib.fnCL) {
Scintilla::ILexer5 *pLexer = lexLib.fnCL(sLanguageName.c_str());
if (pLexer) {
return pLexer;
}
}
}
if (pCreateLexerDefault) {
return pCreateLexerDefault(sLanguageName.c_str());
}
#ifdef LEXILLA_STATIC
Scintilla::ILexer5 *pLexer = CreateLexer(sLanguageName.c_str());
if (pLexer) {
return pLexer;
}
#endif
return nullptr;
}
std::vector<std::string> Lexilla::Lexers() {
return lexers;
}
std::string Lexilla::NameFromID(int identifier) {
for (const LexLibrary &lexLib : libraries) {
if (lexLib.fnLNFI) {
const char *name = lexLib.fnLNFI(identifier);
if (name) {
return name;
}
}
}
return std::string();
}
std::vector<std::string> Lexilla::LibraryProperties() {
return libraryProperties;
}
void Lexilla::SetProperty(const char *key, const char *value) {
for (const LexLibrary &lexLib : libraries) {
if (lexLib.fnSLP) {
lexLib.fnSLP(key, value);
}
}
// Standard Lexilla does not have any properties so don't set.
}