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Diffstat (limited to 'src/lauxlib.c')
| -rw-r--r-- | src/lauxlib.c | 717 |
1 files changed, 717 insertions, 0 deletions
diff --git a/src/lauxlib.c b/src/lauxlib.c new file mode 100644 index 00000000..5bbe918b --- /dev/null +++ b/src/lauxlib.c @@ -0,0 +1,717 @@ +/* +** $Id: lauxlib.c,v 1.127 2004/12/20 13:47:29 roberto Exp $ +** Auxiliary functions for building Lua libraries +** See Copyright Notice in lua.h +*/ + + +#include <ctype.h> +#include <errno.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + + +/* This file uses only the official API of Lua. +** Any function declared here could be written as an application function. +*/ + +#define lauxlib_c +#define LUA_LIB + +#include "lua.h" + +#include "lauxlib.h" + + +/* number of prereserved references (for internal use) */ +#define RESERVED_REFS 2 + +/* reserved references */ +#define FREELIST_REF 1 /* free list of references */ +#define ARRAYSIZE_REF 2 /* array sizes */ + + +/* convert a stack index to positive */ +#define abs_index(L, i) ((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \ + lua_gettop(L) + (i) + 1) + + +/* +** {====================================================== +** Error-report functions +** ======================================================= +*/ + + +LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) { + lua_Debug ar; + lua_getstack(L, 0, &ar); + lua_getinfo(L, "n", &ar); + if (strcmp(ar.namewhat, "method") == 0) { + narg--; /* do not count `self' */ + if (narg == 0) /* error is in the self argument itself? */ + return luaL_error(L, "calling `%s' on bad self (%s)", ar.name, extramsg); + } + if (ar.name == NULL) + ar.name = "?"; + return luaL_error(L, "bad argument #%d to `%s' (%s)", + narg, ar.name, extramsg); +} + + +LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) { + const char *msg = lua_pushfstring(L, "%s expected, got %s", + tname, luaL_typename(L, narg)); + return luaL_argerror(L, narg, msg); +} + + +static void tag_error (lua_State *L, int narg, int tag) { + luaL_typerror(L, narg, lua_typename(L, tag)); +} + + +LUALIB_API void luaL_where (lua_State *L, int level) { + lua_Debug ar; + if (lua_getstack(L, level, &ar)) { /* check function at level */ + lua_getinfo(L, "Sl", &ar); /* get info about it */ + if (ar.currentline > 0) { /* is there info? */ + lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline); + return; + } + } + lua_pushliteral(L, ""); /* else, no information available... */ +} + + +LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) { + va_list argp; + va_start(argp, fmt); + luaL_where(L, 1); + lua_pushvfstring(L, fmt, argp); + va_end(argp); + lua_concat(L, 2); + return lua_error(L); +} + +/* }====================================================== */ + + +LUALIB_API int luaL_findstring (const char *name, const char *const list[]) { + int i; + for (i=0; list[i]; i++) + if (strcmp(list[i], name) == 0) + return i; + return -1; /* name not found */ +} + + +LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) { + lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get registry.name */ + if (!lua_isnil(L, -1)) /* name already in use? */ + return 0; /* leave previous value on top, but return 0 */ + lua_pop(L, 1); + lua_newtable(L); /* create metatable */ + lua_pushvalue(L, -1); + lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */ + lua_pushvalue(L, -1); + lua_pushstring(L, tname); + lua_rawset(L, LUA_REGISTRYINDEX); /* registry[metatable] = name */ + return 1; +} + + +LUALIB_API void luaL_getmetatable (lua_State *L, const char *tname) { + lua_getfield(L, LUA_REGISTRYINDEX, tname); +} + + +LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) { + const char *tn; + if (!lua_getmetatable(L, ud)) return NULL; /* no metatable? */ + lua_rawget(L, LUA_REGISTRYINDEX); /* get registry[metatable] */ + tn = lua_tostring(L, -1); + if (tn && (strcmp(tn, tname) == 0)) { + lua_pop(L, 1); + return lua_touserdata(L, ud); + } + else { + lua_pop(L, 1); + return NULL; + } +} + + +LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) { + if (!lua_checkstack(L, space)) + luaL_error(L, "stack overflow (%s)", mes); +} + + +LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) { + if (lua_type(L, narg) != t) + tag_error(L, narg, t); +} + + +LUALIB_API void luaL_checkany (lua_State *L, int narg) { + if (lua_type(L, narg) == LUA_TNONE) + luaL_argerror(L, narg, "value expected"); +} + + +LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) { + const char *s = lua_tostring(L, narg); + if (!s) tag_error(L, narg, LUA_TSTRING); + if (len) *len = lua_strlen(L, narg); + return s; +} + + +LUALIB_API const char *luaL_optlstring (lua_State *L, int narg, + const char *def, size_t *len) { + if (lua_isnoneornil(L, narg)) { + if (len) + *len = (def ? strlen(def) : 0); + return def; + } + else return luaL_checklstring(L, narg, len); +} + + +LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) { + lua_Number d = lua_tonumber(L, narg); + if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */ + tag_error(L, narg, LUA_TNUMBER); + return d; +} + + +LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) { + if (lua_isnoneornil(L, narg)) return def; + else return luaL_checknumber(L, narg); +} + + +LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) { + lua_Integer d = lua_tointeger(L, narg); + if (d == 0 && !lua_isnumber(L, narg)) /* avoid extra test when d is not 0 */ + tag_error(L, narg, LUA_TNUMBER); + return d; +} + + +LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg, + lua_Integer def) { + if (lua_isnoneornil(L, narg)) return def; + else return luaL_checkinteger(L, narg); +} + + +LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) { + if (!lua_getmetatable(L, obj)) /* no metatable? */ + return 0; + lua_getfield(L, -1, event); + if (lua_isnil(L, -1)) { + lua_pop(L, 2); /* remove metatable and metafield */ + return 0; + } + else { + lua_remove(L, -2); /* remove only metatable */ + return 1; + } +} + + +LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) { + obj = abs_index(L, obj); + if (!luaL_getmetafield(L, obj, event)) /* no metafield? */ + return 0; + lua_pushvalue(L, obj); + lua_call(L, 1, 1); + return 1; +} + + +LUALIB_API void luaL_openlib (lua_State *L, const char *libname, + const luaL_reg *l, int nup) { + if (libname) { + /* check whether lib already exists */ + luaL_getfield(L, LUA_GLOBALSINDEX, libname); + if (lua_isnil(L, -1)) { /* not found? */ + lua_pop(L, 1); /* remove previous result */ + lua_newtable(L); /* create it */ + if (lua_getmetatable(L, LUA_GLOBALSINDEX)) + lua_setmetatable(L, -2); /* share metatable with global table */ + /* register it with given name */ + lua_pushvalue(L, -1); + luaL_setfield(L, LUA_GLOBALSINDEX, libname); + } + else if (!lua_istable(L, -1)) + luaL_error(L, "name conflict for library `%s'", libname); + lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED"); + lua_pushvalue(L, -2); + lua_setfield(L, -2, libname); /* _LOADED[modname] = new table */ + lua_pop(L, 1); /* remove _LOADED table */ + lua_insert(L, -(nup+1)); /* move library table to below upvalues */ + } + for (; l->name; l++) { + int i; + for (i=0; i<nup; i++) /* copy upvalues to the top */ + lua_pushvalue(L, -nup); + lua_pushcclosure(L, l->func, nup); + lua_setfield(L, -(nup+2), l->name); + } + lua_pop(L, nup); /* remove upvalues */ +} + + + +/* +** {====================================================== +** getn-setn: size for arrays +** ======================================================= +*/ + +static int checkint (lua_State *L, int topop) { + int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1; + lua_pop(L, topop); + return n; +} + + +static void getsizes (lua_State *L) { + lua_rawgeti(L, LUA_REGISTRYINDEX, ARRAYSIZE_REF); + if (lua_isnil(L, -1)) { /* no `size' table? */ + lua_pop(L, 1); /* remove nil */ + lua_newtable(L); /* create it */ + lua_pushvalue(L, -1); /* `size' will be its own metatable */ + lua_setmetatable(L, -2); + lua_pushliteral(L, "kv"); + lua_setfield(L, -2, "__mode"); /* metatable(N).__mode = "kv" */ + lua_pushvalue(L, -1); + lua_rawseti(L, LUA_REGISTRYINDEX, ARRAYSIZE_REF); /* store in register */ + } +} + + +LUALIB_API void luaL_setn (lua_State *L, int t, int n) { + t = abs_index(L, t); + getsizes(L); + lua_pushvalue(L, t); + lua_pushinteger(L, n); + lua_rawset(L, -3); /* sizes[t] = n */ + lua_pop(L, 1); /* remove `sizes' */ +} + + +/* find an `n' such that t[n] ~= nil and t[n+1] == nil */ +static int countn (lua_State *L, int t) { + int i = LUA_FIRSTINDEX - 1; + int j = 2; + /* find `i' such that i <= n < i*2 (= j) */ + for (;;) { + lua_rawgeti(L, t, j); + if (lua_isnil(L, -1)) break; + lua_pop(L, 1); + i = j; + j = i*2; + } + lua_pop(L, 1); + /* i <= n < j; do a binary search */ + while (i < j-1) { + int m = (i+j)/2; + lua_rawgeti(L, t, m); + if (lua_isnil(L, -1)) j = m; + else i = m; + lua_pop(L, 1); + } + return i - LUA_FIRSTINDEX + 1; +} + + +LUALIB_API int luaL_getn (lua_State *L, int t) { + int n; + t = abs_index(L, t); + getsizes(L); /* try sizes[t] */ + lua_pushvalue(L, t); + lua_rawget(L, -2); + if ((n = checkint(L, 2)) >= 0) return n; + lua_getfield(L, t, "n"); /* else try t.n */ + if ((n = checkint(L, 1)) >= 0) return n; + return countn(L, t); +} + +/* }====================================================== */ + + +static const char *pushnexttemplate (lua_State *L, const char *path) { + const char *l; + if (*path == '\0') return NULL; /* no more templates */ + if (*path == LUA_PATH_SEP) path++; /* skip separator */ + l = strchr(path, LUA_PATH_SEP); /* find next separator */ + if (l == NULL) l = path+strlen(path); + lua_pushlstring(L, path, l - path); /* template */ + return l; +} + + +LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p, + const char *r) { + const char *wild; + int l = strlen(p); + luaL_Buffer b; + luaL_buffinit(L, &b); + while ((wild = strstr(s, p)) != NULL) { + luaL_addlstring(&b, s, wild - s); /* push prefix */ + luaL_addstring(&b, r); /* push replacement in place of pattern */ + s = wild + l; /* continue after `p' */ + } + luaL_addstring(&b, s); /* push last suffix (`n' already includes this) */ + luaL_pushresult(&b); + return lua_tostring(L, -1); +} + + +static int readable (const char *fname) { + int err; + FILE *f = fopen(fname, "r"); /* try to open file */ + if (f == NULL) return 0; /* open failed */ + getc(f); /* try to read it */ + err = ferror(f); + fclose(f); + return (err == 0); +} + + +LUALIB_API const char *luaL_searchpath (lua_State *L, const char *name, + const char *path) { + const char *p = path; + for (;;) { + const char *fname; + if ((p = pushnexttemplate(L, p)) == NULL) { + lua_pushfstring(L, "no readable `%s' in path `%s'", name, path); + return NULL; + } + fname = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name); + lua_remove(L, -2); /* remove path template */ + if (readable(fname)) /* does file exist and is readable? */ + return fname; /* return that file name */ + lua_pop(L, 1); /* remove file name */ + } +} + + +LUALIB_API const char *luaL_getfield (lua_State *L, int idx, + const char *fname) { + const char *e; + lua_pushvalue(L, idx); + while ((e = strchr(fname, '.')) != NULL) { + lua_pushlstring(L, fname, e - fname); + lua_rawget(L, -2); + lua_remove(L, -2); /* remove previous table */ + fname = e + 1; + if (!lua_istable(L, -1)) return fname; + } + lua_pushstring(L, fname); + lua_rawget(L, -2); /* get last field */ + lua_remove(L, -2); /* remove previous table */ + return NULL; +} + + +LUALIB_API const char *luaL_setfield (lua_State *L, int idx, + const char *fname) { + const char *e; + lua_pushvalue(L, idx); + while ((e = strchr(fname, '.')) != NULL) { + lua_pushlstring(L, fname, e - fname); + lua_rawget(L, -2); + if (lua_isnil(L, -1)) { /* no such field? */ + lua_pop(L, 1); /* remove this nil */ + lua_newtable(L); /* create a new table for field */ + lua_pushlstring(L, fname, e - fname); + lua_pushvalue(L, -2); + lua_settable(L, -4); /* set new table into field */ + } + lua_remove(L, -2); /* remove previous table */ + fname = e + 1; + if (!lua_istable(L, -1)) { + lua_pop(L, 2); /* remove table and value */ + return fname; + } + } + lua_pushstring(L, fname); + lua_pushvalue(L, -3); /* move value to the top */ + lua_rawset(L, -3); /* set last field */ + lua_pop(L, 2); /* remove value and table */ + return NULL; +} + + + +/* +** {====================================================== +** Generic Buffer manipulation +** ======================================================= +*/ + + +#define bufflen(B) ((B)->p - (B)->buffer) +#define bufffree(B) ((size_t)(LUAL_BUFFERSIZE - bufflen(B))) + +#define LIMIT (LUA_MINSTACK/2) + + +static int emptybuffer (luaL_Buffer *B) { + size_t l = bufflen(B); + if (l == 0) return 0; /* put nothing on stack */ + else { + lua_pushlstring(B->L, B->buffer, l); + B->p = B->buffer; + B->lvl++; + return 1; + } +} + + +static void adjuststack (luaL_Buffer *B) { + if (B->lvl > 1) { + lua_State *L = B->L; + int toget = 1; /* number of levels to concat */ + size_t toplen = lua_strlen(L, -1); + do { + size_t l = lua_strlen(L, -(toget+1)); + if (B->lvl - toget + 1 >= LIMIT || toplen > l) { + toplen += l; + toget++; + } + else break; + } while (toget < B->lvl); + lua_concat(L, toget); + B->lvl = B->lvl - toget + 1; + } +} + + +LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) { + if (emptybuffer(B)) + adjuststack(B); + return B->buffer; +} + + +LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) { + while (l--) + luaL_putchar(B, *s++); +} + + +LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) { + luaL_addlstring(B, s, strlen(s)); +} + + +LUALIB_API void luaL_pushresult (luaL_Buffer *B) { + emptybuffer(B); + lua_concat(B->L, B->lvl); + B->lvl = 1; +} + + +LUALIB_API void luaL_addvalue (luaL_Buffer *B) { + lua_State *L = B->L; + size_t vl = lua_strlen(L, -1); + if (vl <= bufffree(B)) { /* fit into buffer? */ + memcpy(B->p, lua_tostring(L, -1), vl); /* put it there */ + B->p += vl; + lua_pop(L, 1); /* remove from stack */ + } + else { + if (emptybuffer(B)) + lua_insert(L, -2); /* put buffer before new value */ + B->lvl++; /* add new value into B stack */ + adjuststack(B); + } +} + + +LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) { + B->L = L; + B->p = B->buffer; + B->lvl = 0; +} + +/* }====================================================== */ + + +LUALIB_API int luaL_ref (lua_State *L, int t) { + int ref; + t = abs_index(L, t); + if (lua_isnil(L, -1)) { + lua_pop(L, 1); /* remove from stack */ + return LUA_REFNIL; /* `nil' has a unique fixed reference */ + } + lua_rawgeti(L, t, FREELIST_REF); /* get first free element */ + ref = (int)lua_tointeger(L, -1); /* ref = t[FREELIST_REF] */ + lua_pop(L, 1); /* remove it from stack */ + if (ref != 0) { /* any free element? */ + lua_rawgeti(L, t, ref); /* remove it from list */ + lua_rawseti(L, t, FREELIST_REF); /* (t[FREELIST_REF] = t[ref]) */ + } + else { /* no free elements */ + ref = luaL_getn(L, t); + if (ref < RESERVED_REFS) + ref = RESERVED_REFS; /* skip reserved references */ + ref++; /* create new reference */ + luaL_setn(L, t, ref); + } + lua_rawseti(L, t, ref); + return ref; +} + + +LUALIB_API void luaL_unref (lua_State *L, int t, int ref) { + if (ref >= 0) { + t = abs_index(L, t); + lua_rawgeti(L, t, FREELIST_REF); + lua_rawseti(L, t, ref); /* t[ref] = t[FREELIST_REF] */ + lua_pushinteger(L, ref); + lua_rawseti(L, t, FREELIST_REF); /* t[FREELIST_REF] = ref */ + } +} + + + +/* +** {====================================================== +** Load functions +** ======================================================= +*/ + +typedef struct LoadF { + int extraline; + FILE *f; + char buff[LUAL_BUFFERSIZE]; +} LoadF; + + +static const char *getF (lua_State *L, void *ud, size_t *size) { + LoadF *lf = (LoadF *)ud; + (void)L; + if (lf->extraline) { + lf->extraline = 0; + *size = 1; + return "\n"; + } + if (feof(lf->f)) return NULL; + *size = fread(lf->buff, 1, LUAL_BUFFERSIZE, lf->f); + return (*size > 0) ? lf->buff : NULL; +} + + +static int errfile (lua_State *L, const char *what, int fnameindex) { + const char *serr = strerror(errno); + const char *filename = lua_tostring(L, fnameindex) + 1; + lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr); + lua_remove(L, fnameindex); + return LUA_ERRFILE; +} + + +LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) { + LoadF lf; + int status, readstatus; + int c; + int fnameindex = lua_gettop(L) + 1; /* index of filename on the stack */ + lf.extraline = 0; + if (filename == NULL) { + lua_pushliteral(L, "=stdin"); + lf.f = stdin; + } + else { + lua_pushfstring(L, "@%s", filename); + lf.f = fopen(filename, "r"); + if (lf.f == NULL) return errfile(L, "open", fnameindex); + } + c = getc(lf.f); + if (c == '#') { /* Unix exec. file? */ + lf.extraline = 1; + while ((c = getc(lf.f)) != EOF && c != '\n') ; /* skip first line */ + if (c == '\n') c = getc(lf.f); + } + if (c == LUA_SIGNATURE[0] && lf.f != stdin) { /* binary file? */ + fclose(lf.f); + lf.f = fopen(filename, "rb"); /* reopen in binary mode */ + if (lf.f == NULL) return errfile(L, "reopen", fnameindex); + /* skip eventual `#!...' */ + while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ; + lf.extraline = 0; + } + ungetc(c, lf.f); + status = lua_load(L, getF, &lf, lua_tostring(L, -1)); + readstatus = ferror(lf.f); + if (lf.f != stdin) fclose(lf.f); /* close file (even in case of errors) */ + if (readstatus) { + lua_settop(L, fnameindex); /* ignore results from `lua_load' */ + return errfile(L, "read", fnameindex); + } + lua_remove(L, fnameindex); + return status; +} + + +typedef struct LoadS { + const char *s; + size_t size; +} LoadS; + + +static const char *getS (lua_State *L, void *ud, size_t *size) { + LoadS *ls = (LoadS *)ud; + (void)L; + if (ls->size == 0) return NULL; + *size = ls->size; + ls->size = 0; + return ls->s; +} + + +LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size, + const char *name) { + LoadS ls; + ls.s = buff; + ls.size = size; + return lua_load(L, getS, &ls, name); +} + + +/* }====================================================== */ + + +static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) { + (void)ud; + (void)osize; + if (nsize == 0) { + free(ptr); + return NULL; + } + else + return realloc(ptr, nsize); +} + + +static int panic (lua_State *L) { + fprintf(stderr, "PANIC: unprotected error during Lua-API call\n"); + return 0; +} + + +LUALIB_API lua_State *luaL_newstate (void) { + lua_State *L = lua_newstate(l_alloc, NULL); + lua_atpanic(L, &panic); + return L; +} + |