CMake/Source/cmGccDepfileLexerHelper.cxx
Joerg Bornemann f8c505d4b3 Add a parser for GCC-style depfiles
Introduce the function cmReadGccDepfile that parses a GCC-style depfile
and returns its content. The implementation uses a lexer that is
modeled after the re2c implementation in Ninja.

The sample files of the autotest have been created with gcc 8.3.0.

This depfile reader is to be used by the Autogen facility to make use
of the depfiles that are generated by Qt's meta object compiler.
2020-01-28 11:16:11 -05:00

127 lines
2.8 KiB
C++

/* Distributed under the OSI-approved BSD 3-Clause License. See accompanying
file Copyright.txt or https://cmake.org/licensing for details. */
#include "cmGccDepfileLexerHelper.h"
#include <cstdio>
#include <memory>
#include <string>
#include <vector>
#include "cmGccDepfileReaderTypes.h"
#include "LexerParser/cmGccDepfileLexer.h"
#ifdef _WIN32
# include "cmsys/Encoding.h"
#endif
bool cmGccDepfileLexerHelper::readFile(const char* filePath)
{
#ifdef _WIN32
wchar_t* wpath = cmsysEncoding_DupToWide(filePath);
FILE* file = _wfopen(wpath, L"rb");
free(wpath);
#else
FILE* file = fopen(filePath, "r");
#endif
if (!file) {
return false;
}
newEntry();
yyscan_t scanner;
cmGccDepfile_yylex_init(&scanner);
cmGccDepfile_yyset_extra(this, scanner);
cmGccDepfile_yyrestart(file, scanner);
cmGccDepfile_yylex(scanner);
cmGccDepfile_yylex_destroy(scanner);
sanitizeContent();
fclose(file);
return true;
}
void cmGccDepfileLexerHelper::newEntry()
{
this->HelperState = State::Rule;
this->Content.emplace_back();
newRule();
}
void cmGccDepfileLexerHelper::newRule()
{
auto& entry = this->Content.back();
if (entry.rules.empty() || !entry.rules.back().empty()) {
entry.rules.emplace_back();
}
}
void cmGccDepfileLexerHelper::newDependency()
{
// printf("NEW DEP\n");
this->HelperState = State::Dependency;
if (this->Content.back().paths.empty() ||
!this->Content.back().paths.back().empty()) {
this->Content.back().paths.emplace_back();
}
}
void cmGccDepfileLexerHelper::newRuleOrDependency()
{
if (this->HelperState == State::Rule) {
newRule();
} else {
newDependency();
}
}
void cmGccDepfileLexerHelper::addToCurrentPath(const char* s)
{
if (this->Content.empty()) {
return;
}
cmGccStyleDependency* dep = &this->Content.back();
std::string* dst = nullptr;
switch (this->HelperState) {
case State::Rule: {
if (dep->rules.empty()) {
return;
}
dst = &dep->rules.back();
} break;
case State::Dependency: {
if (dep->paths.empty()) {
return;
}
dst = &dep->paths.back();
} break;
}
dst->append(s);
}
void cmGccDepfileLexerHelper::sanitizeContent()
{
for (auto it = this->Content.begin(); it != this->Content.end();) {
// Remove empty rules
for (auto rit = it->rules.begin(); rit != it->rules.end();) {
if (rit->empty()) {
rit = it->rules.erase(rit);
} else {
++rit;
}
}
// Remove the entry if rules are empty
if (it->rules.empty()) {
it = this->Content.erase(it);
} else {
// Remove empty paths
for (auto pit = it->paths.begin(); pit != it->paths.end();) {
if (pit->empty()) {
pit = it->paths.erase(pit);
} else {
++pit;
}
}
++it;
}
}
}