moonbridge: 9fa3a36733ff moonbridge

moonbridge

view moonbridge_io.c @ 86:9fa3a36733ff

New I/O methods drain and drain_nb

author	jbe
date	Tue Apr 07 00:47:30 2015 +0200 (2015-04-07)
parents	ef552870f1b6
children	1d91c6eedf18

line source

2 #include <stdlib.h>

3 #include <unistd.h>

4 #include <stdint.h>

5 #include <errno.h>

6 #include <string.h>

7 #include <sys/socket.h>

8 #include <sys/select.h>

9 #include <fcntl.h>

11 #include <lua.h>

12 #include <lauxlib.h>

13 #include <lualib.h>

15 #define MOONBR_IO_MAXSTRERRORLEN 80

16 #define MOONBR_IO_READBUFLEN 4096

17 #define MOONBR_IO_WRITEBUFLEN 4096

19 #define moonbr_io_errmsg() \

20 char errmsg[MOONBR_IO_MAXSTRERRORLEN]; \

21 strerror_r(errno, errmsg, MOONBR_IO_MAXSTRERRORLEN)

23 #define MOONBR_IO_HANDLE_MT_REGKEY "moonbridge_io_handle"

24 #define MOONBR_IO_HANDLE_PUBLIC_MT_REGKEY "moonbridge_io_handle_public"

26 typedef struct {

27 int fd;

28 int issocket;

29 int nonblocking;

30 int readerr;

31 int readbufcnt;

32 int writeerr;

33 size_t writeleft;

34 #if LUA_VERSION_NUM >= 503

35 lua_Integer writeqin;

36 lua_Integer writeqout;

37 #else

38 int writeqin;

39 int writeqout;

40 #endif

41 size_t writeqoff;

42 int writebufcnt;

43 char readbuf[MOONBR_IO_READBUFLEN];

44 char writebuf[MOONBR_IO_WRITEBUFLEN];

45 } moonbr_io_handle_t;

47 static void moonbr_io_handle_set_nonblocking(lua_State *L, moonbr_io_handle_t *handle, int nonblocking) {

48 if (handle->nonblocking != nonblocking) {

49 int flags;

50 flags = fcntl(handle->fd, F_GETFL, 0);

51 if (flags == -1) {

52 moonbr_io_errmsg();

53 luaL_error(L, "Unexpected error in fcntl call: %s", errmsg);

54 }

55 if (nonblocking) flags |= O_NONBLOCK;

56 else flags &= ~O_NONBLOCK;

57 if (fcntl(handle->fd, F_SETFL, flags) == -1) {

58 moonbr_io_errmsg();

59 luaL_error(L, "Unexpected error in fcntl call: %s", errmsg);

60 }

61 }

62 }

64 static int moonbr_io_read_impl(lua_State *L, int nonblocking, int drain) {

65 moonbr_io_handle_t *handle;

66 lua_Integer maxread;

67 const char *terminatorstr;

68 size_t terminatorlen;

69 char terminator;

70 luaL_Buffer luabuf;

71 size_t luabufcnt = 0;

72 int endcnt;

73 char *terminatorpos;

74 ssize_t result;

75 handle = luaL_checkudata(L, 1, MOONBR_IO_HANDLE_MT_REGKEY);

76 maxread = luaL_optinteger(L, 2, 0);

77 terminatorstr = luaL_optlstring(L, 3, "", &terminatorlen);

78 if (terminatorlen) {

79 luaL_argcheck(L, terminatorlen == 1, 3, "single byte expected");

80 terminator = terminatorstr[0];

81 }

82 lua_settop(L, 1); /* return handle on drain, terminator string may be garbage collected */

83 if (handle->fd < 0) luaL_error(L, "Attempt to read from a closed I/O handle");

84 if (handle->readerr) {

85 lua_pushnil(L);

86 lua_pushliteral(L, "Previous read error");

87 return 2;

88 }

89 moonbr_io_handle_set_nonblocking(L, handle, nonblocking);

90 if (!drain) luaL_buffinit(L, &luabuf);

91 while (1) {

92 endcnt = -1;

93 if (maxread > 0 && handle->readbufcnt >= maxread - luabufcnt) {

94 endcnt = maxread - luabufcnt;

95 } else if (terminatorlen) {

96 terminatorpos = memchr(handle->readbuf, terminator, handle->readbufcnt);

97 if (terminatorpos) endcnt = 1 + (terminatorpos - handle->readbuf);

98 }

99 if (endcnt >= 0) {

100 if (!drain) {

101 luaL_addlstring(&luabuf, handle->readbuf, endcnt);

102 luaL_pushresult(&luabuf);

103 }

104 handle->readbufcnt -= endcnt;

105 memmove(handle->readbuf, handle->readbuf + endcnt, handle->readbufcnt);

106 return 1;

107 }

108 if (!drain) luaL_addlstring(&luabuf, handle->readbuf, handle->readbufcnt);

109 luabufcnt += handle->readbufcnt;

110 handle->readbufcnt = 0;

111 do {

112 result = read(handle->fd, handle->readbuf, MOONBR_IO_READBUFLEN);

113 } while (result < 0 && (errno == EINTR));

114 if (result == 0 || (nonblocking && result < 0 && (errno == EAGAIN || errno == EWOULDBLOCK))) break;

115 if (result < 0) {

116 moonbr_io_errmsg();

117 handle->readerr = 1;

118 lua_pushnil(L);

119 lua_pushstring(L, errmsg);

120 return 2;

121 }

122 handle->readbufcnt += result;

123 }

124 if (!drain) {

125 luaL_addlstring(&luabuf, handle->readbuf, handle->readbufcnt);

126 luaL_pushresult(&luabuf);

127 }

128 handle->readbufcnt = 0;

129 return 1;

130 }

131

132 static int moonbr_io_read(lua_State *L) {

133 return moonbr_io_read_impl(L, 0, 0);

134 }

135

136 static int moonbr_io_read_nb(lua_State *L) {

137 return moonbr_io_read_impl(L, 1, 0);

138 }

139

140 static int moonbr_io_drain(lua_State *L) {

141 return moonbr_io_read_impl(L, 0, 1);

142 }

143

144 static int moonbr_io_drain_nb(lua_State *L) {

145 return moonbr_io_read_impl(L, 1, 1);

146 }

147

148 static int moonbr_io_write_impl(lua_State *L, int nonblocking, int flush) {

149 moonbr_io_handle_t *handle;

150 int i, top;

151 const char *str;

152 size_t strlen, strpos;

153 size_t written;

154 ssize_t result;

155 handle = luaL_checkudata(L, 1, MOONBR_IO_HANDLE_MT_REGKEY);

156 if (handle->fd < 0) luaL_error(L, "Attempt to write to a closed I/O handle");

157 if (handle->writeerr) {

158 lua_pushnil(L);

159 lua_pushliteral(L, "Previous write error");

160 return 2;

161 }

162 moonbr_io_handle_set_nonblocking(L, handle, nonblocking);

163 top = lua_gettop(L);

164 lua_getuservalue(L, 1);

165 lua_getfield(L, -1, "writebuf");

166 for (i=2; i<=top; i++) {

167 luaL_checklstring(L, i, &strlen);

168 lua_pushvalue(L, i);

169 lua_rawseti(L, -2, handle->writeqin++);

170 handle->writeleft += strlen;

171 }

172 while (handle->writeqout != handle->writeqin) {

173 lua_rawgeti(L, -1, handle->writeqout);

174 str = lua_tolstring(L, -1, &strlen);

175 strpos = handle->writeqoff;

176 while (strpos < strlen) {

177 if (strlen - strpos < MOONBR_IO_WRITEBUFLEN - handle->writebufcnt) {

178 memcpy(handle->writebuf + handle->writebufcnt, str + strpos, strlen - strpos);

179 handle->writebufcnt += strlen - strpos;

180 break;

181 } else {

182 written = 0;

183 memcpy(handle->writebuf + handle->writebufcnt, str + strpos, MOONBR_IO_WRITEBUFLEN - handle->writebufcnt);

184 strpos += MOONBR_IO_WRITEBUFLEN - handle->writebufcnt;

185 while (written < MOONBR_IO_WRITEBUFLEN) {

186 result = write(handle->fd, handle->writebuf + written, MOONBR_IO_WRITEBUFLEN - written);

187 if (result < 0) {

188 if (nonblocking && (errno == EAGAIN || errno == EWOULDBLOCK)) {

189 if (written) {

190 handle->writebufcnt -= written;

191 memmove(handle->writebuf, handle->writebuf + written, handle->writebufcnt);

192 }

193 handle->writeqoff = strpos;

194 goto moonbr_io_write_impl_block;

195 } else if (errno != EINTR) {

196 moonbr_io_errmsg();

197 handle->writeerr = 1;

198 lua_pushnil(L);

199 lua_pushstring(L, errmsg);

200 return 2;

201 }

202 } else {

203 written += result;

204 handle->writeleft -= result;

205 }

206 }

207 handle->writebufcnt = 0;

208 }

209 }

210 handle->writeqoff = 0;

211 lua_pop(L, 1);

212 lua_pushnil(L);

213 lua_rawseti(L, -2, handle->writeqout++);

214 }

215 if (flush) {

216 written = 0;

217 while (written < handle->writebufcnt) {

218 result = write(handle->fd, handle->writebuf + written, handle->writebufcnt - written);

219 if (result < 0) {

220 if (nonblocking && (errno == EAGAIN || errno == EWOULDBLOCK)) {

221 if (written) {

222 handle->writebufcnt -= written;

223 memmove(handle->writebuf, handle->writebuf + written, handle->writebufcnt);

224 }

225 goto moonbr_io_write_impl_block;

226 } else if (errno != EINTR) {

227 moonbr_io_errmsg();

228 handle->writeerr = -1;

229 lua_pushnil(L);

230 lua_pushstring(L, errmsg);

231 return 2;

232 }

233 } else {

234 written += result;

235 handle->writeleft -= result;

236 }

237 }

238 handle->writebufcnt = 0;

239 if (nonblocking) lua_pushinteger(L, 0);

240 } else {

241 if (nonblocking) lua_pushinteger(L, handle->writeleft - handle->writebufcnt);

242 }

243 if (!nonblocking) lua_pushvalue(L, 1);

244 return 1;

245 moonbr_io_write_impl_block:

246 if (flush) lua_pushinteger(L, handle->writeleft);

247 else lua_pushinteger(L, handle->writeleft - handle->writebufcnt);

248 return 1;

249 }

250

251 static int moonbr_io_write(lua_State *L) {

252 return moonbr_io_write_impl(L, 0, 0);

253 }

254

255 static int moonbr_io_write_nb(lua_State *L) {

256 return moonbr_io_write_impl(L, 1, 0);

257 }

258

259 static int moonbr_io_flush(lua_State *L) {

260 return moonbr_io_write_impl(L, 0, 1);

261 }

262

263 static int moonbr_io_flush_nb(lua_State *L) {

264 return moonbr_io_write_impl(L, 1, 1);

265 }

266

267 static int moonbr_io_close_impl(lua_State *L, int clean) {

268 moonbr_io_handle_t *handle;

269 handle = luaL_checkudata(L, 1, MOONBR_IO_HANDLE_MT_REGKEY);

270 if (handle->fd < 0) luaL_error(L, "Attempt to close a closed I/O handle");

271 if (clean && handle->writeleft) {

272 lua_pushcfunction(L, moonbr_io_flush);

273 lua_pushvalue(L, 1);

274 lua_call(L, 1, 2);

275 if (!lua_toboolean(L, -2)) {

276 close(handle->fd);

277 handle->fd = -1;

278 return 2;

279 }

280 }

281 if (close(handle->fd)) {

282 moonbr_io_errmsg();

283 handle->fd = -1;

284 lua_pushnil(L);

285 lua_pushstring(L, errmsg);

286 return 2;

287 }

288 handle->fd = -1;

289 lua_pushboolean(L, 1);

290 return 1;

291

292 }

293

294 static int moonbr_io_reset(lua_State *L) {

295 return moonbr_io_close_impl(L, 0);

296 }

297

298 static int moonbr_io_close(lua_State *L) {

299 return moonbr_io_close_impl(L, 1);

300 }

301

302 void moonbr_io_pushhandle(lua_State *L, int fd, int issocket) {

303 moonbr_io_handle_t *handle;

304 handle = lua_newuserdata(L, sizeof(moonbr_io_handle_t));

305 handle->fd = fd;

306 handle->issocket = issocket;

307 handle->nonblocking = -1;

308 handle->readerr = 0;

309 handle->readbufcnt = 0;

310 handle->writeerr = 0;

311 handle->writeleft = 0;

312 handle->writeqin = 0;

313 handle->writeqout = 0;

314 handle->writeqoff = 0;

315 handle->writebufcnt = 0;

316 luaL_getmetatable(L, MOONBR_IO_HANDLE_MT_REGKEY);

317 lua_setmetatable(L, -2);

318 lua_newtable(L); // uservalue

319 lua_newtable(L);

320 lua_setfield(L, -2, "writebuf");

321 lua_newtable(L); // public

322 luaL_getmetatable(L, MOONBR_IO_HANDLE_PUBLIC_MT_REGKEY);

323 lua_setmetatable(L, -2);

324 lua_setfield(L, -2, "public");

325 lua_setuservalue(L, -2);

326 }

327

328 static int moonbr_io_handleindex(lua_State *L) {

329 luaL_checkudata(L, 1, MOONBR_IO_HANDLE_MT_REGKEY);

330 lua_getuservalue(L, 1);

331 lua_getfield(L, -1, "public");

332 lua_pushvalue(L, 2);

333 lua_gettable(L, -2);

334 return 1;

335 }

336

337 static int moonbr_io_handlenewindex(lua_State *L) {

338 luaL_checkudata(L, 1, MOONBR_IO_HANDLE_MT_REGKEY);

339 lua_getuservalue(L, 1);

340 lua_getfield(L, -1, "public");

341 lua_pushvalue(L, 2);

342 lua_pushvalue(L, 3);

343 lua_settable(L, -3);

344 return 0;

345 }

346

347 static int moonbr_io_handlegc(lua_State *L) {

348 moonbr_io_handle_t *handle;

349 handle = luaL_checkudata(L, 1, MOONBR_IO_HANDLE_MT_REGKEY);

350 if (handle->fd >= 0) {

351 lua_getuservalue(L, 1);

352 lua_getfield(L, -1, "gc");

353 lua_pushvalue(L, 1);

354 lua_call(L, 1, 0);

355 }

356 return 0;

357 }

358

359 static int moonbr_io_getdummy(lua_State *L) {

360 moonbr_io_pushhandle(L, 0, 0);

361 return 1;

362 }

363

364 static const struct luaL_Reg moonbr_io_handle_methods[] = {

365 {"read", moonbr_io_read},

366 {"read_nb", moonbr_io_read_nb},

367 {"drain", moonbr_io_drain},

368 {"drain_nb", moonbr_io_drain_nb},

369 {"write", moonbr_io_write},

370 {"write_nb", moonbr_io_write_nb},

371 {"flush", moonbr_io_flush},

372 {"flush_nb", moonbr_io_flush_nb},

373 {"reset", moonbr_io_reset},

374 {"close", moonbr_io_close},

375 {NULL, NULL}

376 };

377

378 static const struct luaL_Reg moonbr_io_handle_metamethods[] = {

379 {"__index", moonbr_io_handleindex},

380 {"__newindex", moonbr_io_handlenewindex},

381 {"__gc", moonbr_io_handlegc},

382 {NULL, NULL}

383 };

384

385 static const struct luaL_Reg moonbr_io_module_funcs[] = {

386 {"getdummy", moonbr_io_getdummy},

387 {NULL, NULL}

388 };

389

390 int luaopen_moonbridge_io(lua_State *L) {

391

392 lua_newtable(L); // module

393

394 lua_newtable(L); // public metatable

395 lua_newtable(L); // handle methods

396 luaL_setfuncs(L, moonbr_io_handle_methods, 0);

397 lua_pushvalue(L, -1);

398 lua_setfield(L, -4, "handle");

399 lua_setfield(L, -2, "__index");

400 lua_setfield(L, LUA_REGISTRYINDEX, MOONBR_IO_HANDLE_PUBLIC_MT_REGKEY);

401

402 lua_newtable(L); // handle metatable

403 luaL_setfuncs(L, moonbr_io_handle_metamethods, 0);

404 lua_setfield(L, LUA_REGISTRYINDEX, MOONBR_IO_HANDLE_MT_REGKEY);

405

406 luaL_setfuncs(L, moonbr_io_module_funcs, 0);

407 return 1;

408

409 }

410