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Diffstat (limited to 'src/liolib.c')
-rw-r--r--src/liolib.c556
1 files changed, 556 insertions, 0 deletions
diff --git a/src/liolib.c b/src/liolib.c
new file mode 100644
index 0000000..649f9a5
--- /dev/null
+++ b/src/liolib.c
@@ -0,0 +1,556 @@
+/*
+** $Id: liolib.c,v 2.73.1.4 2010/05/14 15:33:51 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 {
+ lua_pushnil(L); /* "result" to be removed */
+ 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;
+}
+