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#include "yaml-cpp/emitterstyle.h"
#include "yaml-cpp/eventhandler.h"
#include "yaml-cpp/yaml.h" // IWYU pragma: keep
#include <cstdlib>
#include <fstream>
#include <iostream>
class NullEventHandler : public YAML::EventHandler {
public:
using Mark = YAML::Mark;
using anchor_t = YAML::anchor_t;
NullEventHandler() = default;
void OnDocumentStart(const Mark&) override {}
void OnDocumentEnd() override {}
void OnNull(const Mark&, anchor_t) override {}
void OnAlias(const Mark&, anchor_t) override {}
void OnScalar(const Mark&, const std::string&, anchor_t,
const std::string&) override {}
void OnSequenceStart(const Mark&, const std::string&, anchor_t,
YAML::EmitterStyle::value style) override {}
void OnSequenceEnd() override {}
void OnMapStart(const Mark&, const std::string&, anchor_t,
YAML::EmitterStyle::value style) override {}
void OnMapEnd() override {}
};
void run(std::istream& in) {
YAML::Parser parser(in);
NullEventHandler handler;
parser.HandleNextDocument(handler);
}
void usage() { std::cerr << "Usage: read [-n N] [-c, --cache] [filename]\n"; }
std::string read_stream(std::istream& in) {
return std::string((std::istreambuf_iterator<char>(in)),
std::istreambuf_iterator<char>());
}
int main(int argc, char** argv) {
int N = 1;
bool cache = false;
std::string filename;
for (int i = 1; i < argc; i++) {
std::string arg = argv[i];
if (arg == "-n") {
i++;
if (i >= argc) {
usage();
return -1;
}
N = std::atoi(argv[i]);
if (N <= 0) {
usage();
return -1;
}
} else if (arg == "-c" || arg == "--cache") {
cache = true;
} else {
filename = argv[i];
if (i + 1 != argc) {
usage();
return -1;
}
}
}
if (N > 1 && !cache && filename.empty()) {
usage();
return -1;
}
if (cache) {
std::string input;
if (!filename.empty()) {
std::ifstream in(filename);
input = read_stream(in);
} else {
input = read_stream(std::cin);
}
std::istringstream in(input);
for (int i = 0; i < N; i++) {
in.seekg(std::ios_base::beg);
run(in);
}
} else {
if (!filename.empty()) {
std::ifstream in(filename);
for (int i = 0; i < N; i++) {
in.seekg(std::ios_base::beg);
run(in);
}
} else {
for (int i = 0; i < N; i++) {
run(std::cin);
}
}
}
return 0;
}
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