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qpdf/libqpdf/QPDFArgParser.cc

786 lines
26 KiB
C++

#include <qpdf/QPDFArgParser.hh>
#include <qpdf/QIntC.hh>
#include <qpdf/QPDFLogger.hh>
#include <qpdf/QPDFUsage.hh>
#include <qpdf/QTC.hh>
#include <qpdf/QUtil.hh>
#include <cstdlib>
#include <cstring>
#include <iostream>
QPDFArgParser::Members::Members(int argc, char const* const argv[], char const* progname_env) :
argc(argc),
argv(argv),
progname_env(progname_env),
cur_arg(0),
bash_completion(false),
zsh_completion(false),
option_table(nullptr),
final_check_handler(nullptr)
{
auto tmp = QUtil::make_unique_cstr(argv[0]);
whoami = QUtil::getWhoami(tmp.get());
}
QPDFArgParser::QPDFArgParser(int argc, char const* const argv[], char const* progname_env) :
m(new Members(argc, argv, progname_env))
{
selectHelpOptionTable();
char const* help_choices[] = {"all", nullptr};
// More help choices are added dynamically.
addChoices("help", bindParam(&QPDFArgParser::argHelp, this), false, help_choices);
addInvalidChoiceHandler("help", bindParam(&QPDFArgParser::invalidHelpArg, this));
addBare("completion-bash", bindBare(&QPDFArgParser::argCompletionBash, this));
addBare("completion-zsh", bindBare(&QPDFArgParser::argCompletionZsh, this));
selectMainOptionTable();
}
void
QPDFArgParser::selectMainOptionTable()
{
m->option_table = &m->main_option_table;
m->option_table_name = "main";
}
void
QPDFArgParser::selectHelpOptionTable()
{
m->option_table = &m->help_option_table;
m->option_table_name = "help";
}
void
QPDFArgParser::selectOptionTable(std::string const& name)
{
auto t = m->option_tables.find(name);
if (t == m->option_tables.end()) {
QTC::TC("libtests", "QPDFArgParser select unregistered table");
throw std::logic_error("QPDFArgParser: selecting unregistered option table " + name);
}
m->option_table = &(t->second);
m->option_table_name = name;
}
void
QPDFArgParser::registerOptionTable(std::string const& name, bare_arg_handler_t end_handler)
{
if (0 != m->option_tables.count(name)) {
QTC::TC("libtests", "QPDFArgParser register registered table");
throw std::logic_error(
"QPDFArgParser: registering already registered option table " + name);
}
m->option_tables[name];
selectOptionTable(name);
addBare("--", end_handler);
}
QPDFArgParser::OptionEntry&
QPDFArgParser::registerArg(std::string const& arg)
{
if (0 != m->option_table->count(arg)) {
QTC::TC("libtests", "QPDFArgParser duplicate handler");
throw std::logic_error(
"QPDFArgParser: adding a duplicate handler for option " + arg + " in " +
m->option_table_name + " option table");
}
return ((*m->option_table)[arg]);
}
void
QPDFArgParser::addPositional(param_arg_handler_t handler)
{
OptionEntry& oe = registerArg("");
oe.param_arg_handler = handler;
}
void
QPDFArgParser::addBare(std::string const& arg, bare_arg_handler_t handler)
{
OptionEntry& oe = registerArg(arg);
oe.parameter_needed = false;
oe.bare_arg_handler = handler;
}
void
QPDFArgParser::addRequiredParameter(
std::string const& arg, param_arg_handler_t handler, char const* parameter_name)
{
OptionEntry& oe = registerArg(arg);
oe.parameter_needed = true;
oe.parameter_name = parameter_name;
oe.param_arg_handler = handler;
}
void
QPDFArgParser::addOptionalParameter(std::string const& arg, param_arg_handler_t handler)
{
OptionEntry& oe = registerArg(arg);
oe.parameter_needed = false;
oe.param_arg_handler = handler;
}
void
QPDFArgParser::addChoices(
std::string const& arg, param_arg_handler_t handler, bool required, char const** choices)
{
OptionEntry& oe = registerArg(arg);
oe.parameter_needed = required;
oe.param_arg_handler = handler;
for (char const** i = choices; *i; ++i) {
oe.choices.insert(*i);
}
}
void
QPDFArgParser::addInvalidChoiceHandler(std::string const& arg, param_arg_handler_t handler)
{
auto i = m->option_table->find(arg);
if (i == m->option_table->end()) {
QTC::TC("libtests", "QPDFArgParser invalid choice handler to unknown");
throw std::logic_error(
"QPDFArgParser: attempt to add invalid choice handler to unknown argument");
}
auto& oe = i->second;
oe.invalid_choice_handler = handler;
}
void
QPDFArgParser::addFinalCheck(bare_arg_handler_t handler)
{
m->final_check_handler = handler;
}
bool
QPDFArgParser::isCompleting() const
{
return m->bash_completion;
}
int
QPDFArgParser::argsLeft() const
{
return m->argc - m->cur_arg - 1;
}
void
QPDFArgParser::insertCompletion(std::string const& arg)
{
m->completions.insert(arg);
}
void
QPDFArgParser::completionCommon(bool zsh)
{
std::string progname = m->argv[0];
std::string executable;
std::string appdir;
std::string appimage;
if (QUtil::get_env(m->progname_env.c_str(), &executable)) {
progname = executable;
} else if (QUtil::get_env("APPDIR", &appdir) && QUtil::get_env("APPIMAGE", &appimage)) {
// Detect if we're in an AppImage and adjust
if ((appdir.length() < strlen(m->argv[0])) &&
(strncmp(appdir.c_str(), m->argv[0], appdir.length()) == 0)) {
progname = appimage;
}
}
if (zsh) {
std::cout << "autoload -U +X bashcompinit && bashcompinit && ";
}
std::cout << "complete -o bashdefault -o default";
if (!zsh) {
std::cout << " -o nospace";
}
std::cout << " -C \"" << progname << "\" " << m->whoami << std::endl;
// Put output before error so calling from zsh works properly
std::string path = progname;
size_t slash = path.find('/');
if ((slash != 0) && (slash != std::string::npos)) {
std::cerr << "WARNING: " << m->whoami << " completion enabled"
<< " using relative path to executable" << std::endl;
}
}
void
QPDFArgParser::argCompletionBash()
{
completionCommon(false);
}
void
QPDFArgParser::argCompletionZsh()
{
completionCommon(true);
}
void
QPDFArgParser::argHelp(std::string const& p)
{
QPDFLogger::defaultLogger()->info(getHelp(p));
exit(0);
}
void
QPDFArgParser::invalidHelpArg(std::string const& p)
{
usage(std::string("unknown help option") + (p.empty() ? "" : (" " + p)));
}
void
QPDFArgParser::handleArgFileArguments()
{
// Support reading arguments from files. Create a new argv. Ensure that argv itself as well as
// all its contents are automatically deleted by using shared pointers back to the pointers in
// argv.
m->new_argv.push_back(QUtil::make_shared_cstr(m->argv[0]));
for (int i = 1; i < m->argc; ++i) {
char const* argfile = nullptr;
if ((strlen(m->argv[i]) > 1) && (m->argv[i][0] == '@')) {
argfile = 1 + m->argv[i];
if (strcmp(argfile, "-") != 0) {
if (!QUtil::file_can_be_opened(argfile)) {
// The file's not there; treating as regular option
argfile = nullptr;
}
}
}
if (argfile) {
readArgsFromFile(1 + m->argv[i]);
} else {
m->new_argv.push_back(QUtil::make_shared_cstr(m->argv[i]));
}
}
m->argv_ph = QUtil::make_shared_array<char const*>(1 + m->new_argv.size());
for (size_t i = 0; i < m->new_argv.size(); ++i) {
m->argv_ph.get()[i] = m->new_argv.at(i).get();
}
m->argc = QIntC::to_int(m->new_argv.size());
m->argv_ph.get()[m->argc] = nullptr;
m->argv = m->argv_ph.get();
}
void
QPDFArgParser::handleBashArguments()
{
// Do a minimal job of parsing bash_line into arguments. This doesn't do everything the shell
// does (e.g. $(...), variable expansion, arithmetic, globs, etc.), but it should be good enough
// for purposes of handling completion. As we build up the new argv, we can't use m->new_argv
// because this code has to interoperate with @file arguments, so memory for both ways of
// fabricating argv has to be protected.
bool last_was_backslash = false;
enum { st_top, st_squote, st_dquote } state = st_top;
std::string arg;
for (char ch: m->bash_line) {
if (last_was_backslash) {
arg.append(1, ch);
last_was_backslash = false;
} else if (ch == '\\') {
last_was_backslash = true;
} else {
bool append = false;
switch (state) {
case st_top:
if (QUtil::is_space(ch)) {
if (!arg.empty()) {
m->bash_argv.push_back(QUtil::make_shared_cstr(arg));
arg.clear();
}
} else if (ch == '"') {
state = st_dquote;
} else if (ch == '\'') {
state = st_squote;
} else {
append = true;
}
break;
case st_squote:
if (ch == '\'') {
state = st_top;
} else {
append = true;
}
break;
case st_dquote:
if (ch == '"') {
state = st_top;
} else {
append = true;
}
break;
}
if (append) {
arg.append(1, ch);
}
}
}
if (m->bash_argv.empty()) {
// This can't happen if properly invoked by bash, but ensure we have a valid argv[0]
// regardless.
m->bash_argv.push_back(QUtil::make_shared_cstr(m->argv[0]));
}
// Explicitly discard any non-space-terminated word. The "current word" is handled specially.
m->bash_argv_ph = QUtil::make_shared_array<char const*>(1 + m->bash_argv.size());
for (size_t i = 0; i < m->bash_argv.size(); ++i) {
m->bash_argv_ph.get()[i] = m->bash_argv.at(i).get();
}
m->argc = QIntC::to_int(m->bash_argv.size());
m->bash_argv_ph.get()[m->argc] = nullptr;
m->argv = m->bash_argv_ph.get();
}
void
QPDFArgParser::usage(std::string const& message)
{
if (m->bash_completion) {
// This will cause bash to fall back to regular file completion.
exit(0);
}
throw QPDFUsage(message);
}
void
QPDFArgParser::readArgsFromFile(std::string const& filename)
{
std::list<std::string> lines;
if (filename == "-") {
QTC::TC("libtests", "QPDFArgParser read args from stdin");
lines = QUtil::read_lines_from_file(std::cin);
} else {
QTC::TC("libtests", "QPDFArgParser read args from file");
lines = QUtil::read_lines_from_file(filename.c_str());
}
for (auto const& line: lines) {
m->new_argv.push_back(QUtil::make_shared_cstr(line));
}
}
void
QPDFArgParser::checkCompletion()
{
// See if we're being invoked from bash completion.
std::string bash_point_env;
// On Windows with mingw, there have been times when there appears to be no way to distinguish
// between an empty environment variable and an unset variable. There are also conditions under
// which bash doesn't set COMP_LINE. Therefore, enter this logic if either COMP_LINE or
// COMP_POINT are set. They will both be set together under ordinary circumstances.
bool got_line = QUtil::get_env("COMP_LINE", &m->bash_line);
bool got_point = QUtil::get_env("COMP_POINT", &bash_point_env);
if (got_line || got_point) {
size_t p = QUtil::string_to_uint(bash_point_env.c_str());
if (p < m->bash_line.length()) {
// Truncate the line. We ignore everything at or after the
// cursor for completion purposes.
m->bash_line = m->bash_line.substr(0, p);
}
if (p > m->bash_line.length()) {
p = m->bash_line.length();
}
// Set bash_cur and bash_prev based on bash_line rather than relying on argv. This enables
// us to use bashcompinit to get completion in zsh too since bashcompinit sets COMP_LINE and
// COMP_POINT but doesn't invoke the command with options like bash does.
// p is equal to length of the string. Walk backwards looking for the first separator.
// bash_cur is everything after the last separator, possibly empty.
char sep(0);
while (p > 0) {
--p;
char ch = m->bash_line.at(p);
if ((ch == ' ') || (ch == '=') || (ch == ':')) {
sep = ch;
break;
}
}
if (1 + p <= m->bash_line.length()) {
m->bash_cur = m->bash_line.substr(1 + p, std::string::npos);
}
if ((sep == ':') || (sep == '=')) {
// Bash sets prev to the non-space separator if any. Actually, if there are multiple
// separators in a row, they are all included in prev, but that detail is not important
// to us and not worth coding.
m->bash_prev = m->bash_line.substr(p, 1);
} else {
// Go back to the last separator and set prev based on
// that.
size_t p1 = p;
while (p1 > 0) {
--p1;
char ch = m->bash_line.at(p1);
if ((ch == ' ') || (ch == ':') || (ch == '=')) {
m->bash_prev = m->bash_line.substr(p1 + 1, p - p1 - 1);
break;
}
}
}
if (m->bash_prev.empty()) {
m->bash_prev = m->bash_line.substr(0, p);
}
if (m->argc == 1) {
// This is probably zsh using bashcompinit. There are a few differences in the expected
// output.
m->zsh_completion = true;
}
handleBashArguments();
m->bash_completion = true;
}
}
void
QPDFArgParser::parseArgs()
{
selectMainOptionTable();
checkCompletion();
handleArgFileArguments();
for (m->cur_arg = 1; m->cur_arg < m->argc; ++m->cur_arg) {
bool help_option = false;
bool end_option = false;
auto oep = m->option_table->end();
char const* arg = m->argv[m->cur_arg];
std::string parameter;
bool have_parameter = false;
std::string o_arg(arg);
std::string arg_s(arg);
if (strcmp(arg, "--") == 0) {
// Special case for -- option, which is used to break out of subparsers.
oep = m->option_table->find("--");
end_option = true;
if (oep == m->option_table->end()) {
// This is registered automatically, so this can't happen.
throw std::logic_error("QPDFArgParser: -- handler not registered");
}
} else if ((arg[0] == '-') && (strcmp(arg, "-") != 0)) {
++arg;
if (arg[0] == '-') {
// Be lax about -arg vs --arg
++arg;
} else {
QTC::TC("libtests", "QPDFArgParser single dash");
}
// Prevent --=something from being treated as an empty arg by searching for = from after
// the first character. We do this since the empty string in the option table is for
// positional arguments. Besides, it doesn't make sense to have an empty option.
arg_s = arg;
size_t equal_pos = std::string::npos;
if (arg_s.length() > 0) {
equal_pos = arg_s.find('=', 1);
}
if (equal_pos != std::string::npos) {
have_parameter = true;
parameter = arg_s.substr(equal_pos + 1);
arg_s = arg_s.substr(0, equal_pos);
}
if ((!m->bash_completion) && (m->argc == 2) && (m->cur_arg == 1) &&
m->help_option_table.count(arg_s)) {
// Handle help option, which is only valid as the sole option.
QTC::TC("libtests", "QPDFArgParser help option");
oep = m->help_option_table.find(arg_s);
help_option = true;
}
if (!(help_option || arg_s.empty() || (arg_s.at(0) == '-'))) {
oep = m->option_table->find(arg_s);
}
} else {
// The empty string maps to the positional argument handler.
QTC::TC("libtests", "QPDFArgParser positional");
oep = m->option_table->find("");
parameter = arg;
}
if (oep == m->option_table->end()) {
QTC::TC("libtests", "QPDFArgParser unrecognized");
std::string message = "unrecognized argument " + o_arg;
if (m->option_table != &m->main_option_table) {
message += " (" + m->option_table_name + " options must be terminated with --)";
}
usage(message);
}
OptionEntry& oe = oep->second;
if ((oe.parameter_needed && (!have_parameter)) ||
((!oe.choices.empty() && have_parameter && (0 == oe.choices.count(parameter))))) {
std::string message = "--" + arg_s + " must be given as --" + arg_s + "=";
if (oe.invalid_choice_handler) {
oe.invalid_choice_handler(parameter);
// Method should call usage() or exit. Just in case it doesn't...
message += "option";
} else if (!oe.choices.empty()) {
QTC::TC("libtests", "QPDFArgParser required choices");
message += "{";
bool first = true;
for (auto const& choice: oe.choices) {
if (first) {
first = false;
} else {
message += ",";
}
message += choice;
}
message += "}";
} else if (!oe.parameter_name.empty()) {
QTC::TC("libtests", "QPDFArgParser required parameter");
message += oe.parameter_name;
} else {
// should not be possible
message += "option";
}
usage(message);
}
if (oe.bare_arg_handler) {
oe.bare_arg_handler();
} else if (oe.param_arg_handler) {
oe.param_arg_handler(parameter);
}
if (help_option) {
exit(0);
}
if (end_option) {
selectMainOptionTable();
}
}
if (m->bash_completion) {
handleCompletion();
} else {
doFinalChecks();
}
}
std::string
QPDFArgParser::getProgname()
{
return m->whoami;
}
void
QPDFArgParser::doFinalChecks()
{
if (m->option_table != &(m->main_option_table)) {
QTC::TC("libtests", "QPDFArgParser missing --");
usage("missing -- at end of " + m->option_table_name + " options");
}
if (m->final_check_handler != nullptr) {
m->final_check_handler();
}
}
void
QPDFArgParser::addChoicesToCompletions(
option_table_t& option_table, std::string const& option, std::string const& extra_prefix)
{
if (option_table.count(option) != 0) {
OptionEntry& oe = option_table[option];
for (auto const& choice: oe.choices) {
QTC::TC("libtests", "QPDFArgParser complete choices");
m->completions.insert(extra_prefix + choice);
}
}
}
void
QPDFArgParser::addOptionsToCompletions(option_table_t& option_table)
{
for (auto& iter: option_table) {
std::string const& arg = iter.first;
if (arg == "--") {
continue;
}
OptionEntry& oe = iter.second;
std::string base = "--" + arg;
if (oe.param_arg_handler) {
if (m->zsh_completion) {
// zsh doesn't treat = as a word separator, so add all the options so we don't get a
// space after the =.
addChoicesToCompletions(option_table, arg, base + "=");
}
m->completions.insert(base + "=");
}
if (!oe.parameter_needed) {
m->completions.insert(base);
}
}
}
void
QPDFArgParser::insertCompletions(
option_table_t& option_table, std::string const& choice_option, std::string const& extra_prefix)
{
if (!choice_option.empty()) {
addChoicesToCompletions(option_table, choice_option, extra_prefix);
} else if ((!m->bash_cur.empty()) && (m->bash_cur.at(0) == '-')) {
addOptionsToCompletions(option_table);
}
}
void
QPDFArgParser::handleCompletion()
{
std::string extra_prefix;
if (m->completions.empty()) {
// Detect --option=... Bash treats the = as a word separator.
std::string choice_option;
if (m->bash_cur.empty() && (m->bash_prev.length() > 2) && (m->bash_prev.at(0) == '-') &&
(m->bash_prev.at(1) == '-') && (m->bash_line.at(m->bash_line.length() - 1) == '=')) {
choice_option = m->bash_prev.substr(2, std::string::npos);
} else if ((m->bash_prev == "=") && (m->bash_line.length() > (m->bash_cur.length() + 1))) {
// We're sitting at --option=x. Find previous option.
size_t end_mark = m->bash_line.length() - m->bash_cur.length() - 1;
char before_cur = m->bash_line.at(end_mark);
if (before_cur == '=') {
size_t space = m->bash_line.find_last_of(' ', end_mark);
if (space != std::string::npos) {
std::string candidate = m->bash_line.substr(space + 1, end_mark - space - 1);
if ((candidate.length() > 2) && (candidate.at(0) == '-') &&
(candidate.at(1) == '-')) {
choice_option = candidate.substr(2, std::string::npos);
}
}
}
}
if (m->zsh_completion && (!choice_option.empty())) {
// zsh wants --option=choice rather than just choice
extra_prefix = "--" + choice_option + "=";
}
insertCompletions(*m->option_table, choice_option, extra_prefix);
if (m->argc == 1) {
// Help options are valid only by themselves.
insertCompletions(m->help_option_table, choice_option, extra_prefix);
}
}
std::string prefix = extra_prefix + m->bash_cur;
for (auto const& iter: m->completions) {
if (prefix.empty() || (iter.substr(0, prefix.length()) == prefix)) {
std::cout << iter << std::endl;
}
}
exit(0);
}
void
QPDFArgParser::addHelpFooter(std::string const& text)
{
m->help_footer = "\n" + text;
}
void
QPDFArgParser::addHelpTopic(
std::string const& topic, std::string const& short_text, std::string const& long_text)
{
if (topic == "all") {
QTC::TC("libtests", "QPDFArgParser add reserved help topic");
throw std::logic_error("QPDFArgParser: can't register reserved help topic " + topic);
}
if (!((topic.length() > 0) && (topic.at(0) != '-'))) {
QTC::TC("libtests", "QPDFArgParser bad topic for help");
throw std::logic_error("QPDFArgParser: help topics must not start with -");
}
if (m->help_topics.count(topic)) {
QTC::TC("libtests", "QPDFArgParser add existing topic");
throw std::logic_error("QPDFArgParser: topic " + topic + " has already been added");
}
m->help_topics[topic] = HelpTopic(short_text, long_text);
m->help_option_table["help"].choices.insert(topic);
}
void
QPDFArgParser::addOptionHelp(
std::string const& option_name,
std::string const& topic,
std::string const& short_text,
std::string const& long_text)
{
if (!((option_name.length() > 2) && (option_name.at(0) == '-') && (option_name.at(1) == '-'))) {
QTC::TC("libtests", "QPDFArgParser bad option for help");
throw std::logic_error("QPDFArgParser: options for help must start with --");
}
if (m->option_help.count(option_name)) {
QTC::TC("libtests", "QPDFArgParser duplicate option help");
throw std::logic_error("QPDFArgParser: option " + option_name + " already has help");
}
auto ht = m->help_topics.find(topic);
if (ht == m->help_topics.end()) {
QTC::TC("libtests", "QPDFArgParser add to unknown topic");
throw std::logic_error(
"QPDFArgParser: unable to add option " + option_name + " to unknown help topic " +
topic);
}
m->option_help[option_name] = HelpTopic(short_text, long_text);
ht->second.options.insert(option_name);
m->help_option_table["help"].choices.insert(option_name);
}
void
QPDFArgParser::getTopHelp(std::ostringstream& msg)
{
msg << "Run \"" << m->whoami << " --help=topic\" for help on a topic." << std::endl
<< "Run \"" << m->whoami << " --help=--option\" for help on an option." << std::endl
<< "Run \"" << m->whoami << " --help=all\" to see all available help." << std::endl
<< std::endl
<< "Topics:" << std::endl;
for (auto const& i: m->help_topics) {
msg << " " << i.first << ": " << i.second.short_text << std::endl;
}
}
void
QPDFArgParser::getAllHelp(std::ostringstream& msg)
{
getTopHelp(msg);
auto show = [this, &msg](std::map<std::string, HelpTopic>& topics) {
for (auto const& i: topics) {
auto const& topic = i.first;
msg << std::endl
<< "== " << topic << " (" << i.second.short_text << ") ==" << std::endl
<< std::endl;
getTopicHelp(topic, i.second, msg);
}
};
show(m->help_topics);
show(m->option_help);
msg << std::endl << "====" << std::endl;
}
void
QPDFArgParser::getTopicHelp(std::string const& name, HelpTopic const& ht, std::ostringstream& msg)
{
if (ht.long_text.empty()) {
msg << ht.short_text << std::endl;
} else {
msg << ht.long_text;
}
if (!ht.options.empty()) {
msg << std::endl << "Related options:" << std::endl;
for (auto const& i: ht.options) {
msg << " " << i << ": " << m->option_help[i].short_text << std::endl;
}
}
}
std::string
QPDFArgParser::getHelp(std::string const& arg)
{
std::ostringstream msg;
if (arg.empty()) {
getTopHelp(msg);
} else {
if (arg == "all") {
getAllHelp(msg);
} else if (m->option_help.count(arg)) {
getTopicHelp(arg, m->option_help[arg], msg);
} else if (m->help_topics.count(arg)) {
getTopicHelp(arg, m->help_topics[arg], msg);
} else {
// should not be possible
getTopHelp(msg);
}
}
msg << m->help_footer;
return msg.str();
}