| /* |
| ** $Id: liolib.c,v 2.73.1.3 2008/01/18 17:47:43 roberto Exp $ |
| ** Standard I/O (and system) library |
| ** See Copyright Notice in lua.h |
| */ |
| |
| |
| #include <errno.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #define liolib_c |
| #define LUA_LIB |
| |
| #include "lua.h" |
| |
| #include "lauxlib.h" |
| #include "lualib.h" |
| |
| |
| |
| #define IO_INPUT 1 |
| #define IO_OUTPUT 2 |
| |
| |
| static const char *const fnames[] = {"input", "output"}; |
| |
| |
| static int pushresult (lua_State *L, int i, const char *filename) { |
| int en = errno; /* calls to Lua API may change this value */ |
| if (i) { |
| lua_pushboolean(L, 1); |
| return 1; |
| } |
| else { |
| lua_pushnil(L); |
| if (filename) |
| lua_pushfstring(L, "%s: %s", filename, strerror(en)); |
| else |
| lua_pushfstring(L, "%s", strerror(en)); |
| lua_pushinteger(L, en); |
| return 3; |
| } |
| } |
| |
| |
| static void fileerror (lua_State *L, int arg, const char *filename) { |
| lua_pushfstring(L, "%s: %s", filename, strerror(errno)); |
| luaL_argerror(L, arg, lua_tostring(L, -1)); |
| } |
| |
| |
| #define tofilep(L) ((FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE)) |
| |
| |
| static int io_type (lua_State *L) { |
| void *ud; |
| luaL_checkany(L, 1); |
| ud = lua_touserdata(L, 1); |
| lua_getfield(L, LUA_REGISTRYINDEX, LUA_FILEHANDLE); |
| if (ud == NULL || !lua_getmetatable(L, 1) || !lua_rawequal(L, -2, -1)) |
| lua_pushnil(L); /* not a file */ |
| else if (*((FILE **)ud) == NULL) |
| lua_pushliteral(L, "closed file"); |
| else |
| lua_pushliteral(L, "file"); |
| return 1; |
| } |
| |
| |
| static FILE *tofile (lua_State *L) { |
| FILE **f = tofilep(L); |
| if (*f == NULL) |
| luaL_error(L, "attempt to use a closed file"); |
| return *f; |
| } |
| |
| |
| |
| /* |
| ** When creating file handles, always creates a `closed' file handle |
| ** before opening the actual file; so, if there is a memory error, the |
| ** file is not left opened. |
| */ |
| static FILE **newfile (lua_State *L) { |
| FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *)); |
| *pf = NULL; /* file handle is currently `closed' */ |
| luaL_getmetatable(L, LUA_FILEHANDLE); |
| lua_setmetatable(L, -2); |
| return pf; |
| } |
| |
| |
| /* |
| ** function to (not) close the standard files stdin, stdout, and stderr |
| */ |
| static int io_noclose (lua_State *L) { |
| lua_pushnil(L); |
| lua_pushliteral(L, "cannot close standard file"); |
| return 2; |
| } |
| |
| |
| /* |
| ** function to close 'popen' files |
| */ |
| static int io_pclose (lua_State *L) { |
| FILE **p = tofilep(L); |
| int ok = lua_pclose(L, *p); |
| *p = NULL; |
| return pushresult(L, ok, NULL); |
| } |
| |
| |
| /* |
| ** function to close regular files |
| */ |
| static int io_fclose (lua_State *L) { |
| FILE **p = tofilep(L); |
| int ok = (fclose(*p) == 0); |
| *p = NULL; |
| return pushresult(L, ok, NULL); |
| } |
| |
| |
| static int aux_close (lua_State *L) { |
| lua_getfenv(L, 1); |
| lua_getfield(L, -1, "__close"); |
| return (lua_tocfunction(L, -1))(L); |
| } |
| |
| |
| static int io_close (lua_State *L) { |
| if (lua_isnone(L, 1)) |
| lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT); |
| tofile(L); /* make sure argument is a file */ |
| return aux_close(L); |
| } |
| |
| |
| static int io_gc (lua_State *L) { |
| FILE *f = *tofilep(L); |
| /* ignore closed files */ |
| if (f != NULL) |
| aux_close(L); |
| return 0; |
| } |
| |
| |
| static int io_tostring (lua_State *L) { |
| FILE *f = *tofilep(L); |
| if (f == NULL) |
| lua_pushliteral(L, "file (closed)"); |
| else |
| lua_pushfstring(L, "file (%p)", f); |
| return 1; |
| } |
| |
| |
| static int io_open (lua_State *L) { |
| const char *filename = luaL_checkstring(L, 1); |
| const char *mode = luaL_optstring(L, 2, "r"); |
| FILE **pf = newfile(L); |
| *pf = fopen(filename, mode); |
| return (*pf == NULL) ? pushresult(L, 0, filename) : 1; |
| } |
| |
| |
| /* |
| ** this function has a separated environment, which defines the |
| ** correct __close for 'popen' files |
| */ |
| static int io_popen (lua_State *L) { |
| const char *filename = luaL_checkstring(L, 1); |
| const char *mode = luaL_optstring(L, 2, "r"); |
| FILE **pf = newfile(L); |
| *pf = lua_popen(L, filename, mode); |
| return (*pf == NULL) ? pushresult(L, 0, filename) : 1; |
| } |
| |
| |
| static int io_tmpfile (lua_State *L) { |
| FILE **pf = newfile(L); |
| *pf = tmpfile(); |
| return (*pf == NULL) ? pushresult(L, 0, NULL) : 1; |
| } |
| |
| |
| static FILE *getiofile (lua_State *L, int findex) { |
| FILE *f; |
| lua_rawgeti(L, LUA_ENVIRONINDEX, findex); |
| f = *(FILE **)lua_touserdata(L, -1); |
| if (f == NULL) |
| luaL_error(L, "standard %s file is closed", fnames[findex - 1]); |
| return f; |
| } |
| |
| |
| static int g_iofile (lua_State *L, int f, const char *mode) { |
| if (!lua_isnoneornil(L, 1)) { |
| const char *filename = lua_tostring(L, 1); |
| if (filename) { |
| FILE **pf = newfile(L); |
| *pf = fopen(filename, mode); |
| if (*pf == NULL) |
| fileerror(L, 1, filename); |
| } |
| else { |
| tofile(L); /* check that it's a valid file handle */ |
| lua_pushvalue(L, 1); |
| } |
| lua_rawseti(L, LUA_ENVIRONINDEX, f); |
| } |
| /* return current value */ |
| lua_rawgeti(L, LUA_ENVIRONINDEX, f); |
| return 1; |
| } |
| |
| |
| static int io_input (lua_State *L) { |
| return g_iofile(L, IO_INPUT, "r"); |
| } |
| |
| |
| static int io_output (lua_State *L) { |
| return g_iofile(L, IO_OUTPUT, "w"); |
| } |
| |
| |
| static int io_readline (lua_State *L); |
| |
| |
| static void aux_lines (lua_State *L, int idx, int toclose) { |
| lua_pushvalue(L, idx); |
| lua_pushboolean(L, toclose); /* close/not close file when finished */ |
| lua_pushcclosure(L, io_readline, 2); |
| } |
| |
| |
| static int f_lines (lua_State *L) { |
| tofile(L); /* check that it's a valid file handle */ |
| aux_lines(L, 1, 0); |
| return 1; |
| } |
| |
| |
| static int io_lines (lua_State *L) { |
| if (lua_isnoneornil(L, 1)) { /* no arguments? */ |
| /* will iterate over default input */ |
| lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT); |
| return f_lines(L); |
| } |
| else { |
| const char *filename = luaL_checkstring(L, 1); |
| FILE **pf = newfile(L); |
| *pf = fopen(filename, "r"); |
| if (*pf == NULL) |
| fileerror(L, 1, filename); |
| aux_lines(L, lua_gettop(L), 1); |
| return 1; |
| } |
| } |
| |
| |
| /* |
| ** {====================================================== |
| ** READ |
| ** ======================================================= |
| */ |
| |
| |
| static int read_number (lua_State *L, FILE *f) { |
| lua_Number d; |
| if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) { |
| lua_pushnumber(L, d); |
| return 1; |
| } |
| else return 0; /* read fails */ |
| } |
| |
| |
| static int test_eof (lua_State *L, FILE *f) { |
| int c = getc(f); |
| ungetc(c, f); |
| lua_pushlstring(L, NULL, 0); |
| return (c != EOF); |
| } |
| |
| |
| static int read_line (lua_State *L, FILE *f) { |
| luaL_Buffer b; |
| luaL_buffinit(L, &b); |
| for (;;) { |
| size_t l; |
| char *p = luaL_prepbuffer(&b); |
| if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) { /* eof? */ |
| luaL_pushresult(&b); /* close buffer */ |
| return (lua_objlen(L, -1) > 0); /* check whether read something */ |
| } |
| l = strlen(p); |
| if (l == 0 || p[l-1] != '\n') |
| luaL_addsize(&b, l); |
| else { |
| luaL_addsize(&b, l - 1); /* do not include `eol' */ |
| luaL_pushresult(&b); /* close buffer */ |
| return 1; /* read at least an `eol' */ |
| } |
| } |
| } |
| |
| |
| static int read_chars (lua_State *L, FILE *f, size_t n) { |
| size_t rlen; /* how much to read */ |
| size_t nr; /* number of chars actually read */ |
| luaL_Buffer b; |
| luaL_buffinit(L, &b); |
| rlen = LUAL_BUFFERSIZE; /* try to read that much each time */ |
| do { |
| char *p = luaL_prepbuffer(&b); |
| if (rlen > n) rlen = n; /* cannot read more than asked */ |
| nr = fread(p, sizeof(char), rlen, f); |
| luaL_addsize(&b, nr); |
| n -= nr; /* still have to read `n' chars */ |
| } while (n > 0 && nr == rlen); /* until end of count or eof */ |
| luaL_pushresult(&b); /* close buffer */ |
| return (n == 0 || lua_objlen(L, -1) > 0); |
| } |
| |
| |
| static int g_read (lua_State *L, FILE *f, int first) { |
| int nargs = lua_gettop(L) - 1; |
| int success; |
| int n; |
| clearerr(f); |
| if (nargs == 0) { /* no arguments? */ |
| success = read_line(L, f); |
| n = first+1; /* to return 1 result */ |
| } |
| else { /* ensure stack space for all results and for auxlib's buffer */ |
| luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments"); |
| success = 1; |
| for (n = first; nargs-- && success; n++) { |
| if (lua_type(L, n) == LUA_TNUMBER) { |
| size_t l = (size_t)lua_tointeger(L, n); |
| success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l); |
| } |
| else { |
| const char *p = lua_tostring(L, n); |
| luaL_argcheck(L, p && p[0] == '*', n, "invalid option"); |
| switch (p[1]) { |
| case 'n': /* number */ |
| success = read_number(L, f); |
| break; |
| case 'l': /* line */ |
| success = read_line(L, f); |
| break; |
| case 'a': /* file */ |
| read_chars(L, f, ~((size_t)0)); /* read MAX_SIZE_T chars */ |
| success = 1; /* always success */ |
| break; |
| default: |
| return luaL_argerror(L, n, "invalid format"); |
| } |
| } |
| } |
| } |
| if (ferror(f)) |
| return pushresult(L, 0, NULL); |
| if (!success) { |
| lua_pop(L, 1); /* remove last result */ |
| lua_pushnil(L); /* push nil instead */ |
| } |
| return n - first; |
| } |
| |
| |
| static int io_read (lua_State *L) { |
| return g_read(L, getiofile(L, IO_INPUT), 1); |
| } |
| |
| |
| static int f_read (lua_State *L) { |
| return g_read(L, tofile(L), 2); |
| } |
| |
| |
| static int io_readline (lua_State *L) { |
| FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1)); |
| int sucess; |
| if (f == NULL) /* file is already closed? */ |
| luaL_error(L, "file is already closed"); |
| sucess = read_line(L, f); |
| if (ferror(f)) |
| return luaL_error(L, "%s", strerror(errno)); |
| if (sucess) return 1; |
| else { /* EOF */ |
| if (lua_toboolean(L, lua_upvalueindex(2))) { /* generator created file? */ |
| lua_settop(L, 0); |
| lua_pushvalue(L, lua_upvalueindex(1)); |
| aux_close(L); /* close it */ |
| } |
| return 0; |
| } |
| } |
| |
| /* }====================================================== */ |
| |
| |
| static int g_write (lua_State *L, FILE *f, int arg) { |
| int nargs = lua_gettop(L) - 1; |
| int status = 1; |
| for (; nargs--; arg++) { |
| if (lua_type(L, arg) == LUA_TNUMBER) { |
| /* optimization: could be done exactly as for strings */ |
| status = status && |
| fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0; |
| } |
| else { |
| size_t l; |
| const char *s = luaL_checklstring(L, arg, &l); |
| status = status && (fwrite(s, sizeof(char), l, f) == l); |
| } |
| } |
| return pushresult(L, status, NULL); |
| } |
| |
| |
| static int io_write (lua_State *L) { |
| return g_write(L, getiofile(L, IO_OUTPUT), 1); |
| } |
| |
| |
| static int f_write (lua_State *L) { |
| return g_write(L, tofile(L), 2); |
| } |
| |
| |
| static int f_seek (lua_State *L) { |
| static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END}; |
| static const char *const modenames[] = {"set", "cur", "end", NULL}; |
| FILE *f = tofile(L); |
| int op = luaL_checkoption(L, 2, "cur", modenames); |
| long offset = luaL_optlong(L, 3, 0); |
| op = fseek(f, offset, mode[op]); |
| if (op) |
| return pushresult(L, 0, NULL); /* error */ |
| else { |
| lua_pushinteger(L, ftell(f)); |
| return 1; |
| } |
| } |
| |
| |
| static int f_setvbuf (lua_State *L) { |
| static const int mode[] = {_IONBF, _IOFBF, _IOLBF}; |
| static const char *const modenames[] = {"no", "full", "line", NULL}; |
| FILE *f = tofile(L); |
| int op = luaL_checkoption(L, 2, NULL, modenames); |
| lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE); |
| int res = setvbuf(f, NULL, mode[op], sz); |
| return pushresult(L, res == 0, NULL); |
| } |
| |
| |
| |
| static int io_flush (lua_State *L) { |
| return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL); |
| } |
| |
| |
| static int f_flush (lua_State *L) { |
| return pushresult(L, fflush(tofile(L)) == 0, NULL); |
| } |
| |
| |
| static const luaL_Reg iolib[] = { |
| {"close", io_close}, |
| {"flush", io_flush}, |
| {"input", io_input}, |
| {"lines", io_lines}, |
| {"open", io_open}, |
| {"output", io_output}, |
| {"popen", io_popen}, |
| {"read", io_read}, |
| {"tmpfile", io_tmpfile}, |
| {"type", io_type}, |
| {"write", io_write}, |
| {NULL, NULL} |
| }; |
| |
| |
| static const luaL_Reg flib[] = { |
| {"close", io_close}, |
| {"flush", f_flush}, |
| {"lines", f_lines}, |
| {"read", f_read}, |
| {"seek", f_seek}, |
| {"setvbuf", f_setvbuf}, |
| {"write", f_write}, |
| {"__gc", io_gc}, |
| {"__tostring", io_tostring}, |
| {NULL, NULL} |
| }; |
| |
| |
| static void createmeta (lua_State *L) { |
| luaL_newmetatable(L, LUA_FILEHANDLE); /* create metatable for file handles */ |
| lua_pushvalue(L, -1); /* push metatable */ |
| lua_setfield(L, -2, "__index"); /* metatable.__index = metatable */ |
| luaL_register(L, NULL, flib); /* file methods */ |
| } |
| |
| |
| static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) { |
| *newfile(L) = f; |
| if (k > 0) { |
| lua_pushvalue(L, -1); |
| lua_rawseti(L, LUA_ENVIRONINDEX, k); |
| } |
| lua_pushvalue(L, -2); /* copy environment */ |
| lua_setfenv(L, -2); /* set it */ |
| lua_setfield(L, -3, fname); |
| } |
| |
| |
| static void newfenv (lua_State *L, lua_CFunction cls) { |
| lua_createtable(L, 0, 1); |
| lua_pushcfunction(L, cls); |
| lua_setfield(L, -2, "__close"); |
| } |
| |
| |
| LUALIB_API int luaopen_io (lua_State *L) { |
| createmeta(L); |
| /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */ |
| newfenv(L, io_fclose); |
| lua_replace(L, LUA_ENVIRONINDEX); |
| /* open library */ |
| luaL_register(L, LUA_IOLIBNAME, iolib); |
| /* create (and set) default files */ |
| newfenv(L, io_noclose); /* close function for default files */ |
| createstdfile(L, stdin, IO_INPUT, "stdin"); |
| createstdfile(L, stdout, IO_OUTPUT, "stdout"); |
| createstdfile(L, stderr, 0, "stderr"); |
| lua_pop(L, 1); /* pop environment for default files */ |
| lua_getfield(L, -1, "popen"); |
| newfenv(L, io_pclose); /* create environment for 'popen' */ |
| lua_setfenv(L, -2); /* set fenv for 'popen' */ |
| lua_pop(L, 1); /* pop 'popen' */ |
| return 1; |
| } |
| |