path: root/lib/lua/src/lua.c

/*
** $Id: lua.c,v 1.160.1.2 2007/12/28 15:32:23 roberto Exp $
** Lua stand-alone interpreter
** See Copyright Notice in lua.h
*/


#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define lua_c

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"



static lua_State *globalL = NULL;

static const char *progname = LUA_PROGNAME;



static void lstop (lua_State *L, lua_Debug *ar) {
  (void)ar;  /* unused arg. */
  lua_sethook(L, NULL, 0, 0);
  luaL_error(L, "interrupted!");
}


static void laction (int i) {
  signal(i, SIG_DFL); /* if another SIGINT happens before lstop,
                              terminate process (default action) */
  lua_sethook(globalL, lstop, LUA_MASKCALL | LUA_MASKRET | LUA_MASKCOUNT, 1);
}


static void print_usage (void) {
  fprintf(stderr,
  "usage: %s [options] [script [args]].\n"
  "Available options are:\n"
  "  -e stat  execute string " LUA_QL("stat") "\n"
  "  -l name  require library " LUA_QL("name") "\n"
  "  -i       enter interactive mode after executing " LUA_QL("script") "\n"
  "  -v       show version information\n"
  "  --       stop handling options\n"
  "  -        execute stdin and stop handling options\n"
  ,
  progname);
  fflush(stderr);
}


static void l_message (const char *pname, const char *msg) {
  if (pname) fprintf(stderr, "%s: ", pname);
  fprintf(stderr, "%s\n", msg);
  fflush(stderr);
}


static int report (lua_State *L, int status) {
  if (status && !lua_isnil(L, -1)) {
    const char *msg = lua_tostring(L, -1);
    if (msg == NULL) msg = "(error object is not a string)";
    l_message(progname, msg);
    lua_pop(L, 1);
  }
  return status;
}


static int traceback (lua_State *L) {
  if (!lua_isstring(L, 1))  /* 'message' not a string? */
    return 1;  /* keep it intact */
  lua_getfield(L, LUA_GLOBALSINDEX, "debug");
  if (!lua_istable(L, -1)) {
    lua_pop(L, 1);
    return 1;
  }
  lua_getfield(L, -1, "traceback");
  if (!lua_isfunction(L, -1)) {
    lua_pop(L, 2);
    return 1;
  }
  lua_pushvalue(L, 1);  /* pass error message */
  lua_pushinteger(L, 2);  /* skip this function and traceback */
  lua_call(L, 2, 1);  /* call debug.traceback */
  return 1;
}


static int docall (lua_State *L, int narg, int clear) {
  int status;
  int base = lua_gettop(L) - narg;  /* function index */
  lua_pushcfunction(L, traceback);  /* push traceback function */
  lua_insert(L, base);  /* put it under chunk and args */
  signal(SIGINT, laction);
  status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base);
  signal(SIGINT, SIG_DFL);
  lua_remove(L, base);  /* remove traceback function */
  /* force a complete garbage collection in case of errors */
  if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
  return status;
}


static void print_version (void) {
  l_message(NULL, LUA_RELEASE "  " LUA_COPYRIGHT);
}


static int getargs (lua_State *L, char **argv, int n) {
  int narg;
  int i;
  int argc = 0;
  while (argv[argc]) argc++;  /* count total number of arguments */
  narg = argc - (n + 1);  /* number of arguments to the script */
  luaL_checkstack(L, narg + 3, "too many arguments to script");
  for (i=n+1; i < argc; i++)
    lua_pushstring(L, argv[i]);
  lua_createtable(L, narg, n + 1);
  for (i=0; i < argc; i++) {
    lua_pushstring(L, argv[i]);
    lua_rawseti(L, -2, i - n);
  }
  return narg;
}


static int dofile (lua_State *L, const char *name) {
  int status = luaL_loadfile(L, name) || docall(L, 0, 1);
  return report(L, status);
}


static int dostring (lua_State *L, const char *s, const char *name) {
  int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1);
  return report(L, status);
}


static int dolibrary (lua_State *L, const char *name) {
  lua_getglobal(L, "require");
  lua_pushstring(L, name);
  return report(L, docall(L, 1, 1));
}


static const char *get_prompt (lua_State *L, int firstline) {
  const char *p;
  lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2");
  p = lua_tostring(L, -1);
  if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);
  lua_pop(L, 1);  /* remove global */
  return p;
}


static int incomplete (lua_State *L, int status) {
  if (status == LUA_ERRSYNTAX) {
    size_t lmsg;
    const char *msg = lua_tolstring(L, -1, &lmsg);
    const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1);
    if (strstr(msg, LUA_QL("<eof>")) == tp) {
      lua_pop(L, 1);
      return 1;
    }
  }
  return 0;  /* else... */
}


static int pushline (lua_State *L, int firstline) {
  char buffer[LUA_MAXINPUT];
  char *b = buffer;
  size_t l;
  const char *prmt = get_prompt(L, firstline);
  if (lua_readline(L, b, prmt) == 0)
    return 0;  /* no input */
  l = strlen(b);
  if (l > 0 && b[l-1] == '\n')  /* line ends with newline? */
    b[l-1] = '\0';  /* remove it */
  if (firstline && b[0] == '=')  /* first line starts with `=' ? */
    lua_pushfstring(L, "return %s", b+1);  /* change it to `return' */
  else
    lua_pushstring(L, b);
  lua_freeline(L, b);
  return 1;
}


static int loadline (lua_State *L) {
  int status;
  lua_settop(L, 0);
  if (!pushline(L, 1))
    return -1;  /* no input */
  for (;;) {  /* repeat until gets a complete line */
    status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
    if (!incomplete(L, status)) break;  /* cannot try to add lines? */
    if (!pushline(L, 0))  /* no more input? */
      return -1;
    lua_pushliteral(L, "\n");  /* add a new line... */
    lua_insert(L, -2);  /* ...between the two lines */
    lua_concat(L, 3);  /* join them */
  }
  lua_saveline(L, 1);
  lua_remove(L, 1);  /* remove line */
  return status;
}


static void dotty (lua_State *L) {
  int status;
  const char *oldprogname = progname;
  progname = NULL;
  while ((status = loadline(L)) != -1) {
    if (status == 0) status = docall(L, 0, 0);
    report(L, status);
    if (status == 0 && lua_gettop(L) > 0) {  /* any result to print? */
      lua_getglobal(L, "print");
      lua_insert(L, 1);
      if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
        l_message(progname, lua_pushfstring(L,
                               "error calling " LUA_QL("print") " (%s)",
                               lua_tostring(L, -1)));
    }
  }
  lua_settop(L, 0);  /* clear stack */
  fputs("\n", stdout);
  fflush(stdout);
  progname = oldprogname;
}


static int handle_script (lua_State *L, char **argv, int n) {
  int status;
  const char *fname;
  int narg = getargs(L, argv, n);  /* collect arguments */
  lua_setglobal(L, "arg");
  fname = argv[n];
  if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0) 
    fname = NULL;  /* stdin */
  status = luaL_loadfile(L, fname);
  lua_insert(L, -(narg+1));
  if (status == 0)
    status = docall(L, narg, 0);
  else
    lua_pop(L, narg);      
  return report(L, status);
}


/* check that argument has no extra characters at the end */
#define notail(x)	{if ((x)[2] != '\0') return -1;}


static int collectargs (char **argv, int *pi, int *pv, int *pe) {
  int i;
  for (i = 1; argv[i] != NULL; i++) {
    if (argv[i][0] != '-')  /* not an option? */
        return i;
    switch (argv[i][1]) {  /* option */
      case '-':
        notail(argv[i]);
        return (argv[i+1] != NULL ? i+1 : 0);
      case '\0':
        return i;
      case 'i':
        notail(argv[i]);
        *pi = 1;  /* go through */
      case 'v':
        notail(argv[i]);
        *pv = 1;
        break;
      case 'e':
        *pe = 1;  /* go through */
      case 'l':
        if (argv[i][2] == '\0') {
          i++;
          if (argv[i] == NULL) return -1;
        }
        break;
      default: return -1;  /* invalid option */
    }
  }
  return 0;
}


static int runargs (lua_State *L, char **argv, int n) {
  int i;
  for (i = 1; i < n; i++) {
    if (argv[i] == NULL) continue;
    lua_assert
	curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT_MS,
			request.connect_timeout);

	if (request.useragent != ""case 'e': {
        const char *chunk = argv[i] + 2;
        if (*chunk == '\0') chunk = argv[++i];
        lua_assert(chunk != NULL);
        if (dostring(L, chunk, "=(command line)") != 0)
          return 1;
        break;
      }
      case 'l': {
        const char *filename = argv[i] + 2;
        if (*filename == '\0') filename = argv[++i];
        lua_assert(filename != NULL);
        if (dolibrary(L, filename))
          return 1;  /* stop if file fails */
        break;
      }
      default: break;
    }
  }
  return 0;
}


static int handle_luainit (lua_State *L) {
  const char *init = getenv(LUA_INIT);
  if (init == NULL) return 0;  /* status OK */
  else if (init[0] == '@')
    return dofile(L, init+1);
  else
    return dostring(L, init, "=" LUA_INIT);
}


struct Smain {
  int argc;
  char **argv;
  int status;
};


static int pmain (lua_State *L) {
  struct Smain *s = (struct Smain *)lua_touserdata(L, 1);
  char **argv = s->argv;
  int script;
  int has_i = 0, has_v = 0
				str += "&";
			str += urlencode(it->first);
			str += "=";
			str += urlencode(it->second);
		}
		curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
				str.size());
		curl_easy_setopt(curl, CURLOPT_COPYPOSTFIELDS,
				str.c_str());
	} else {
		curl_easy_setopt(curl, CURLOPT_POST, 1);
		curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
				request.post_data.size());
		curl_easy_setopt(curl, CURLOPT_POSTFIELDS,
				request.post_data.c_str());
		// request.post_data must now *never* be
		// modified until CURLOPT_POSTFIELDS is cleared
	}
	// Set additional HTTP headers
	for (std::vector<std::string>::iterator it = request.extra_headers.begin();
			it != request.extra_headers.end(); ++it) {
		http_header = curl_slist_append(http_header, it->c_str());
	}
	curl_easy_setopt(curl, CURLOPT_HTTPHEADER, http_header);

	if (!g_settings->getBool("curl_verify_cert")) {
		curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, false);
	}
}

CURLcode HTTPFetchOngoing::start(CURLM *multi_)
{
	if (!curl)
		return CURLE_FAILED_INIT;

	if (!multi_) {
		// Easy interface (sync)
		return curl_easy_perform(curl);
	}

	// Multi interface (async)
	CURLMcode mres = curl_multi_add_handle(multi_, curl);
	if (mres != CURLM_OK) {
		errorstream << "curl_multi_add_handle"
			<< " returned error code " << mres
			<< std::endl;
		return CURLE_FAILED_INIT;
	}
	multi = multi_; // store for curl_multi_remove_handle
	return CURLE_OK;
}

const HTTPFetchResult * HTTPFetchOngoing::complete(CURLcode res)
{
	result.succeeded = (res == CURLE_OK);
	result.timeout = (res == CURLE_OPERATION_TIMEDOUT);
	result.data = oss.str();

	// Get HTTP/FTP response code
	result.response_code = 0;
	if (curl && (curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE,
				&result.response_code) != CURLE_OK)) {
		// We failed to get a return code, make sure it is still 0
		result.response_code = 0;
	}

	if (res != CURLE_OK) {
		errorstream << request.url << " not found ("
			<< curl_easy_strerror(res) << ")"
			<< " (response code " << result.response_code << ")"
			<< std::endl;
	}

	return &result;
}

HTTPFetchOngoing::~HTTPFetchOngoing()
{
	if (multi) {
		CURLMcode mres = curl_multi_remove_handle(multi, curl);
		if (mres != CURLM_OK) {
			errorstream << "curl_multi_remove_handle"
				<< " returned error code " << mres
				<< std::endl;
		}
	}

	// Set safe options for the reusable cURL handle
	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
			httpfetch_discardfunction);
	curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
	curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);
	if (http_header) {
		curl_easy_setopt(curl, CURLOPT_HTTPHEADER, NULL);
		curl_slist_free_all(http_header);
	}
	if (post) {
		curl_easy_setopt(curl, CURLOPT_HTTPPOST, NULL);
		curl_formfree(post);
	}

	// Store the cURL handle for reuse
	pool->free(curl);
}


class CurlFetchThread : public Thread
{
protected:
	enum RequestType {
		RT_FETCH,
		RT_CLEAR,
		RT_WAKEUP,
	};

	struct Request {
		RequestType type;
		HTTPFetchRequest fetch_request;
		Event *event;
	};

	CURLM *m_multi;
	MutexedQueue<Request> m_requests;
	size_t m_parallel_limit;

	// Variables exclusively used within thread
	std::vector<HTTPFetchOngoing*> m_all_ongoing;
	std::list<HTTPFetchRequest> m_queued_fetches;

public:
	CurlFetchThread(int parallel_limit) :
		Thread("CurlFetch")
	{
		if (parallel_limit >= 1)
			m_parallel_limit = parallel_limit;
		else
			m_parallel_limit = 1;
	}

	void requestFetch(const HTTPFetchRequest &fetch_request)
	{
		Request req;
		req.type = RT_FETCH;
		req.fetch_request = fetch_request;
		req.event = NULL;
		m_requests.push_back(req);
	}

	void requestClear(unsigned long caller, Event *event)
	{
		Request req;
		req.type = RT_CLEAR;
		req.fetch_request.caller = caller;
		req.event = event;
		m_requests.push_back(req);
	}

	void requestWakeUp()
	{
		Request req;
		req.type = RT_WAKEUP;
		req.event = NULL;
		m_requests.push_back(req);
	}

protected:
	// Handle a request from some other thread
	// E.g. new fetch; clear fetches for one caller; wake up
	void processRequest(const Request &req)
	{
		if (req.type == RT_FETCH) {
			// New fetch, queue until there are less
			// than m_parallel_limit ongoing fetches
			m_queued_fetches.push_back(req.fetch_request);

			// see processQueued() for what happens next

		}
		else if (req.type == RT_CLEAR) {
			unsigned long caller = req.fetch_request.caller;

			// Abort all ongoing fetches for the caller
			for (std::vector<HTTPFetchOngoing*>::iterator
					it = m_all_ongoing.begin();
					it != m_all_ongoing.end();) {
				if ((*it)->getRequest().caller == caller) {
					delete (*it);
					it = m_all_ongoing.erase(it);
				} else {
					++it;
				}
			}

			// Also abort all queued fetches for the caller
			for (std::list<HTTPFetchRequest>::iterator
					it = m_queued_fetches.begin();
					it != m_queued_fetches.end();) {
				if ((*it).caller == caller)
					it = m_queued_fetches.erase(it);
				else
					++it;
			}
		}
		else if (req.type == RT_WAKEUP) {
			// Wakeup: Nothing to do, thread is awake at this point
		}

		if (req.event != NULL)
			req.event->signal();
	}

	// Start new ongoing fetches if m_parallel_limit allows
	void processQueued(CurlHandlePool *pool)
	{
		while (m_all_ongoing.size() < m_parallel_limit &&
				!m_queued_fetches.empty()) {
			HTTPFetchRequest request = m_queued_fetches.front();
			m_queued_fetches.pop_front();

			// Create ongoing fetch data and make a cURL handle
			// Set cURL options based on HTTPFetchRequest
			HTTPFetchOngoing *ongoing =
				new HTTPFetchOngoing(request, pool);

			// Initiate the connection (curl_multi_add_handle)
			CURLcode res = ongoing->start(m_multi);
			if (res == CURLE_OK) {
				m_all_ongoing.push_back(ongoing);
			}
			else {
				httpfetch_deliver_result(*ongoing->complete(res));
				delete ongoing;
			}
		}
	}

	// Process CURLMsg (indicates completion of a fetch)
	void processCurlMessage(CURLMsg *msg)
	{
		// Determine which ongoing fetch the message pertains to
		size_t i = 0;
		bool found = false;
		for (i = 0; i < m_all_ongoing.size(); ++i) {
			if (m_all_ongoing[i]->getEasyHandle() == msg->easy_handle) {
				found = true;
				break;
			}
		}
		if (msg->msg == CURLMSG_DONE && found) {
			// m_all_ongoing[i] succeeded or failed.
			HTTPFetchOngoing *ongoing = m_all_ongoing[i];
			httpfetch_deliver_result(*ongoing->complete(msg->data.result));
			delete ongoing;
			m_all_ongoing.erase(m_all_ongoing.begin() + i);
		}
	}

	// Wait for a request from another thread, or timeout elapses
	void waitForRequest(long timeout)
	{
		if (m_queued_fetches.empty()) {
			try {
				Request req = m_requests.pop_front(timeout);
				processRequest(req);
			}
			catch (ItemNotFoundException &e) {}
		}
	}

	// Wait until some IO happens, or timeout elapses
	void waitForIO(long timeout)
	{
		fd_set read_fd_set;
		fd_set write_fd_set;
		fd_set exc_fd_set;
		int max_fd;
		long select_timeout = -1;
		struct timeval select_tv;
		CURLMcode mres;

		FD_ZERO(&read_fd_set);
		FD_ZERO(&write_fd_set);
		FD_ZERO(&exc_fd_set);

		mres = curl_multi_fdset(m_multi, &read_fd_set,
				&write_fd_set, &exc_fd_set, &max_fd);
		if (mres != CURLM_OK) {
			errorstream<<"curl_multi_fdset"
				<<" returned error code "<<mres
				<<std::endl;
			select_timeout = 0;
		}

		mres = curl_multi_timeout(m_multi, &select_timeout);
		if (mres != CURLM_OK) {
			errorstream<<"curl_multi_timeout"
				<<" returned error code "<<mres
				<<std::endl;
			select_timeout = 0;
		}

		// Limit timeout so new requests get through
		if (select_timeout < 0 || select_timeout > timeout)
			select_timeout = timeout;

		if (select_timeout > 0) {
			// in Winsock it is forbidden to pass three empty
			// fd_sets to select(), so in that case use sleep_ms
			if (max_fd != -1) {
				select_tv.tv_sec = select_timeout / 1000;
				select_tv.tv_usec = (select_timeout % 1000) * 1000;
				int retval = select(max_fd + 1, &read_fd_set,
						&write_fd_set, &exc_fd_set,
						&select_tv);
				if (retval == -1) {
					#ifdef _WIN32
					errorstream<<"select returned error code "
						<<WSAGetLastError()<<std::endl;
					#else
					errorstream<<"select returned error code "
						<<errno<<std::endl;
					#endif
				}
			}
			else {
				sleep_ms(select_timeout);
			}
		}
	}

	void *run()
	{
		DSTACK(FUNCTION_NAME);

		CurlHandlePool pool;

		m_multi = curl_multi_init();
		if (m_multi == NULL) {
			errorstream<<"curl_multi_init returned NULL\n";
			return NULL;
		}

		FATAL_ERROR_IF(!m_all_ongoing.empty(), "Expected empty");

		while (!stopRequested()) {
			BEGIN_DEBUG_EXCEPTION_HANDLER

			/*
				Handle new async requests
			*/

			while (!m_requests.empty()) {
				Request req = m_requests.pop_frontNoEx();
				processRequest(req);
			}
			processQueued(&pool);

			/*
				Handle ongoing async requests
			*/

			int still_ongoing = 0;
			while (curl_multi_perform(m_multi, &still_ongoing) ==
					CURLM_CALL_MULTI_PERFORM)
				/* noop */;

			/*
				Handle completed async requests
			*/
			if (still_ongoing < (int) m_all_ongoing.size()) {
				CURLMsg *msg;
				int msgs_in_queue;
				msg = curl_multi_info_read(m_multi, &msgs_in_queue);
				while (msg != NULL) {
					processCurlMessage(msg);
					msg = curl_multi_info_read(m_multi, &msgs_in_queue);
				}
			}

			/*
				If there are ongoing requests, wait for data
				(with a timeout of 100ms so that new requests
				can be processed).

				If no ongoing requests, wait for a new request.
				(Possibly an empty request that signals
				that the thread should be stopped.)
			*/
			if (m_all_ongoing.empty())
				waitForRequest(100000000);
			else
				waitForIO(100);

			END_DEBUG_EXCEPTION_HANDLER
		}

		// Call curl_multi_remove_handle and cleanup easy handles
		for (size_t i = 0; i < m_all_ongoing.size(); ++i) {
			delete m_all_ongoing[i];
		}
		m_all_ongoing.clear();

		m_queued_fetches.clear();

		CURLMcode mres = curl_multi_cleanup(m_multi);
		if (mres != CURLM_OK) {
			errorstream<<"curl_multi_cleanup"
				<<" returned error code "<<mres
				<<std::endl;
		}

		return NULL;
	}
};

CurlFetchThread *g_httpfetch_thread = NULL;

void httpfetch_init(int parallel_limit)
{
	verbosestream<<"httpfetch_init: parallel_limit="<<parallel_limit
			<<std::endl;

	CURLcode res = curl_global_init(CURL_GLOBAL_DEFAULT);
	FATAL_ERROR_IF(res != CURLE_OK, "CURL init failed");

	g_httpfetch_thread = new CurlFetchThread(parallel_limit);

	// Initialize g_callerid_randomness for httpfetch_caller_alloc_secure
	u64 randbuf[2];
	porting::secure_rand_fill_buf(randbuf, sizeof(u64) * 2);
	g_callerid_randomness = PcgRandom(randbuf[0], randbuf[1]);
}

void httpfetch_cleanup()
{
	verbosestream<<"httpfetch_cleanup: cleaning up"<<std::endl;

	g_httpfetch_thread->stop();
	g_httpfetch_thread->requestWakeUp();
	g_httpfetch_thread->wait();
	delete g_httpfetch_thread;

	curl_global_cleanup();
}

void httpfetch_async(const HTTPFetchRequest &fetch_request)
{
	g_httpfetch_thread->requestFetch(fetch_request);
	if (!g_httpfetch_thread->isRunning())
		g_httpfetch_thread->start();
}

static void httpfetch_request_clear(unsigned long caller)
{
	if (g_httpfetch_thread->isRunning()) {
		Event event;
		g_httpfetch_thread->requestClear(caller, &event);
		event.wait();
	} else {
		g_httpfetch_thread->requestClear(caller, NULL);
	}
}

void httpfetch_sync(const HTTPFetchRequest &fetch_request,
		HTTPFetchResult &fetch_result)
{
	// Create ongoing fetch data and make a cURL handle
	// Set cURL options based on HTTPFetchRequest
	CurlHandlePool pool;
	HTTPFetchOngoing ongoing(fetch_request, &pool);
	// Do the fetch (curl_easy_perform)
	CURLcode res = ongoing.start(NULL);
	// Update fetch result
	fetch_result = *ongoing.complete(res);
}

#else  // USE_CURL

/*
	USE_CURL is off:

	Dummy httpfetch implementation that always returns an error.
*/

void httpfetch_init(int parallel_limit)
{
}

void httpfetch_cleanup()
{
}

void httpfetch_async(const HTTPFetchRequest &fetch_request)
{
	errorstream << "httpfetch_async: unable to fetch " << fetch_request.url
			<< " because USE_CURL=0" << std::endl;

	HTTPFetchResult fetch_result(fetch_request); // sets succeeded = false etc.
	httpfetch_deliver_result(fetch_result);
}

static void httpfetch_request_clear(unsigned long caller)
{
}

void httpfetch_sync(const HTTPFetchRequest &fetch_request,
		HTTPFetchResult &fetch_result)
{
	errorstream << "httpfetch_sync: unable to fetch " << fetch_request.url
			<< " because USE_CURL=0" << std::endl;

	fetch_result = HTTPFetchResult(fetch_request); // sets succeeded = false etc.
}

#endif  // USE_CURL