2 * nixio - Linux I/O library for lua
4 * Copyright (C) 2009 Steven Barth <steven@midlink.org>
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
27 static int nixio_file(lua_State *L) {
28 const char *filename = luaL_checklstring(L, 1, NULL);
29 const char *mode = luaL_optlstring(L, 2, "r", NULL);
31 FILE *file = fopen(filename, mode);
33 return nixio__perror(L);
36 FILE **udata = lua_newuserdata(L, sizeof(FILE*));
38 return luaL_error(L, "out of memory");
43 luaL_getmetatable(L, NIXIO_FILE_META);
44 lua_setmetatable(L, -2);
49 static int nixio_pipe(lua_State *L) {
53 return nixio__perror(L);
56 luaL_getmetatable(L, NIXIO_FILE_META);
57 udata = lua_newuserdata(L, sizeof(FILE*));
59 return luaL_error(L, "out of memory");
62 if (!(*udata = fdopen(pipefd[0], "r"))) {
63 return nixio__perror(L);
66 lua_setmetatable(L, -2);
69 udata = lua_newuserdata(L, sizeof(FILE**));
70 if (!(*udata = fdopen(pipefd[1], "w"))) {
71 return nixio__perror(L);
74 lua_setmetatable(L, -2);
79 static int nixio_file_write(lua_State *L) {
80 FILE *fp = nixio__checkfile(L);
82 const char *data = luaL_checklstring(L, 2, &len);
83 written = fwrite(data, sizeof(char), len, fp);
85 return nixio__perror(L);
87 lua_pushnumber(L, written);
93 /* Some code borrowed from Lua 5.1.4 liolib.c */
94 static int nixio_file_read(lua_State *L) {
95 FILE *f = nixio__checkfile(L);
96 size_t n = (size_t)luaL_checkinteger(L, 2);
97 luaL_argcheck(L, 2, n >= 0, "invalid length");
103 lua_pushliteral(L, "");
108 size_t rlen; /* how much to read */
109 size_t nr; /* number of chars actually read */
111 luaL_buffinit(L, &b);
112 rlen = LUAL_BUFFERSIZE; /* try to read that much each time */
115 char *p = luaL_prepbuffer(&b);
116 if (rlen > n) rlen = n; /* cannot read more than asked */
117 nr = fread(p, sizeof(char), rlen, f);
118 luaL_addsize(&b, nr);
119 n -= nr; /* still have to read `n' chars */
120 } while (n > 0 && nr == rlen); /* until end of count or eof */
121 luaL_pushresult(&b); /* close buffer */
122 return (n == 0 || lua_objlen(L, -1) > 0);
125 static int nixio_file_seek(lua_State *L) {
126 FILE *f = nixio__checkfile(L);
127 off_t len = (off_t)luaL_checknumber(L, 2);
129 const char *whstr = luaL_optlstring(L, 3, "set", NULL);
130 if (!strcmp(whstr, "set")) {
132 } else if (!strcmp(whstr, "cur")) {
134 } else if (!strcmp(whstr, "end")) {
137 return luaL_argerror(L, 3, "supported values: set, cur, end");
139 return nixio__pstatus(L, !fseeko(f, len, whence));
142 static int nixio_file_tell(lua_State *L) {
143 FILE *f = nixio__checkfile(L);
144 off_t pos = ftello(f);
146 return nixio__perror(L);
148 lua_pushnumber(L, (lua_Number)pos);
153 static int nixio_file_flush(lua_State *L) {
154 FILE *f = nixio__checkfile(L);
155 return nixio__pstatus(L, !fflush(f));
158 static int nixio_file_close(lua_State *L) {
159 FILE **fpp = (FILE**)luaL_checkudata(L, 1, NIXIO_FILE_META);
160 luaL_argcheck(L, *fpp, 1, "invalid file object");
161 int res = fclose(*fpp);
163 return nixio__pstatus(L, !res);
166 static int nixio_file__gc(lua_State *L) {
167 FILE **fpp = (FILE**)luaL_checkudata(L, 1, NIXIO_FILE_META);
176 * string representation
178 static int nixio_file__tostring(lua_State *L) {
179 lua_pushfstring(L, "nixio file %d", nixio__tofd(L, 1));
184 static const luaL_reg M[] = {
185 {"write", nixio_file_write},
186 {"read", nixio_file_read},
187 {"tell", nixio_file_tell},
188 {"seek", nixio_file_seek},
189 {"flush", nixio_file_flush},
190 {"close", nixio_file_close},
191 {"__gc", nixio_file__gc},
192 {"__tostring", nixio_file__tostring},
197 static const luaL_reg R[] = {
198 {"open", nixio_file},
199 {"pipe", nixio_pipe},
203 void nixio_open_file(lua_State *L) {
204 luaL_register(L, NULL, R);
206 luaL_newmetatable(L, NIXIO_FILE_META);
207 luaL_register(L, NULL, M);
208 lua_pushvalue(L, -1);
209 lua_setfield(L, -2, "__index");