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**));
39 luaL_getmetatable(L, NIXIO_FILE_META);
40 lua_setmetatable(L, -2);
45 static int nixio_pipe(lua_State *L) {
49 return nixio__perror(L);
52 luaL_getmetatable(L, NIXIO_FILE_META);
53 udata = lua_newuserdata(L, sizeof(FILE**));
54 if (!(*udata = fdopen(pipefd[0], "r"))) {
55 return nixio__perror(L);
58 lua_setmetatable(L, -2);
61 udata = lua_newuserdata(L, sizeof(FILE**));
62 if (!(*udata = fdopen(pipefd[1], "w"))) {
63 return nixio__perror(L);
66 lua_setmetatable(L, -2);
71 static int nixio_file_write(lua_State *L) {
72 FILE *fp = nixio__checkfile(L);
74 const char *data = luaL_checklstring(L, 2, &len);
75 written = fwrite(data, sizeof(char), len, fp);
77 return nixio__perror(L);
79 lua_pushnumber(L, written);
85 /* Some code borrowed from Lua 5.1.4 liolib.c */
86 static int nixio_file_read(lua_State *L) {
87 FILE *f = nixio__checkfile(L);
88 size_t n = (size_t)luaL_checkinteger(L, 2);
89 luaL_argcheck(L, 2, n >= 0, "invalid length");
95 lua_pushliteral(L, "");
100 size_t rlen; /* how much to read */
101 size_t nr; /* number of chars actually read */
103 luaL_buffinit(L, &b);
104 rlen = LUAL_BUFFERSIZE; /* try to read that much each time */
107 char *p = luaL_prepbuffer(&b);
108 if (rlen > n) rlen = n; /* cannot read more than asked */
109 nr = fread(p, sizeof(char), rlen, f);
110 luaL_addsize(&b, nr);
111 n -= nr; /* still have to read `n' chars */
112 } while (n > 0 && nr == rlen); /* until end of count or eof */
113 luaL_pushresult(&b); /* close buffer */
114 return (n == 0 || lua_objlen(L, -1) > 0);
117 static int nixio_file_seek(lua_State *L) {
118 FILE *f = nixio__checkfile(L);
119 off_t len = (off_t)luaL_checknumber(L, 2);
121 const char *whstr = luaL_optlstring(L, 3, "set", NULL);
122 if (!strcmp(whstr, "set")) {
124 } else if (!strcmp(whstr, "cur")) {
126 } else if (!strcmp(whstr, "end")) {
129 return luaL_argerror(L, 3, "supported values: set, cur, end");
131 return nixio__pstatus(L, !fseeko(f, len, whence));
134 static int nixio_file_tell(lua_State *L) {
135 FILE *f = nixio__checkfile(L);
136 off_t pos = ftello(f);
138 return nixio__perror(L);
140 lua_pushnumber(L, (lua_Number)pos);
145 static int nixio_file_flush(lua_State *L) {
146 FILE *f = nixio__checkfile(L);
147 return nixio__pstatus(L, !fflush(f));
150 static int nixio_file_close(lua_State *L) {
151 FILE **fpp = (FILE**)luaL_checkudata(L, 1, NIXIO_FILE_META);
152 luaL_argcheck(L, *fpp, 1, "invalid file object");
153 int res = fclose(*fpp);
155 return nixio__pstatus(L, !res);
158 static int nixio_file__gc(lua_State *L) {
159 FILE **fpp = (FILE**)luaL_checkudata(L, 1, NIXIO_FILE_META);
168 * string representation
170 static int nixio_file__tostring(lua_State *L) {
171 lua_pushfstring(L, "nixio file %d", nixio__tofd(L, 1));
176 static const luaL_reg M[] = {
177 {"write", nixio_file_write},
178 {"read", nixio_file_read},
179 {"tell", nixio_file_tell},
180 {"seek", nixio_file_seek},
181 {"flush", nixio_file_flush},
182 {"close", nixio_file_close},
183 {"__gc", nixio_file__gc},
184 {"__tostring", nixio_file__tostring},
189 static const luaL_reg R[] = {
190 {"open", nixio_file},
191 {"pipe", nixio_pipe},
195 void nixio_open_file(lua_State *L) {
196 luaL_register(L, NULL, R);
198 luaL_newmetatable(L, NIXIO_FILE_META);
199 luaL_register(L, NULL, M);
200 lua_pushvalue(L, -1);
201 lua_setfield(L, -2, "__index");