From 2fc6b55dae7a120b4272ca0e9c356d1f96053bd9 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Wed, 31 Oct 2018 16:25:29 -0300 Subject: [PATCH] Removed resource-related "emergency collections" New to-be-closed variables is a better way to ensure the proper release of resources. --- lauxlib.c | 43 ------------------------------------------- lauxlib.h | 2 -- liolib.c | 21 ++------------------- loslib.c | 2 -- manual/manual.of | 14 -------------- 5 files changed, 2 insertions(+), 80 deletions(-) diff --git a/lauxlib.c b/lauxlib.c index 53b8c9bb..78dfb4e9 100644 --- a/lauxlib.c +++ b/lauxlib.c @@ -290,49 +290,6 @@ LUALIB_API int luaL_execresult (lua_State *L, int stat) { /* }====================================================== */ -/* -** {====================================================== -** 'luaL_resourcetryagain' -** This function uses 'errno' to check whether the last error was -** related to lack of resources (e.g., not enough memory or too many -** open files). If so, the function performs a full garbage collection -** to try to release resources, and then it returns 1 to signal to -** the caller that it is worth trying again the failed operation. -** Otherwise, it returns 0. Because error codes are not ANSI C, the -** code must handle any combination of error codes that are defined. -** ======================================================= -*/ - -LUALIB_API int luaL_resourcetryagain (lua_State *L) { - -/* these are the resource-related errors in Linux */ -#if defined(EMFILE) || defined(ENFILE) || defined(ENOMEM) - -#if !defined(EMFILE) /* too many open files in the process */ -#define EMFILE -1 /* if not defined, use an impossible value */ -#endif - -#if !defined(ENFILE) /* too many open files in the system */ -#define ENFILE -1 -#endif - -#if !defined(ENOMEM) /* not enough memory */ -#define ENOMEM -1 -#endif - - if (errno == EMFILE || errno == ENFILE || errno == ENOMEM) { - lua_gc(L, LUA_GCCOLLECT); /* try to release resources with a full GC */ - return 1; /* signal to try again the creation */ - } - -#endif - - return 0; /* else, asume errors are not due to lack of resources */ - -} - -/* }====================================================== */ - /* ** {====================================================== diff --git a/lauxlib.h b/lauxlib.h index cd4d01e5..9ec0f531 100644 --- a/lauxlib.h +++ b/lauxlib.h @@ -77,8 +77,6 @@ LUALIB_API int (luaL_checkoption) (lua_State *L, int arg, const char *def, LUALIB_API int (luaL_fileresult) (lua_State *L, int stat, const char *fname); LUALIB_API int (luaL_execresult) (lua_State *L, int stat); -LUALIB_API int (luaL_resourcetryagain) (lua_State *L); - /* predefined references */ #define LUA_NOREF (-2) diff --git a/liolib.c b/liolib.c index 5881b029..b2a2fec8 100644 --- a/liolib.c +++ b/liolib.c @@ -246,22 +246,9 @@ static LStream *newfile (lua_State *L) { } -/* -** Equivalent to 'fopen', but if it fails due to a lack of resources -** (see 'luaL_resourcetryagain'), do an "emergency" garbage collection -** to try to close some files and then tries to open the file again. -*/ -static FILE *trytoopen (lua_State *L, const char *path, const char *mode) { - FILE *f = fopen(path, mode); - if (f == NULL && luaL_resourcetryagain(L)) /* resource failure? */ - f = fopen(path, mode); /* try to open again */ - return f; -} - - static void opencheck (lua_State *L, const char *fname, const char *mode) { LStream *p = newfile(L); - p->f = trytoopen(L, fname, mode); + p->f = fopen(fname, mode); if (p->f == NULL) luaL_error(L, "cannot open file '%s' (%s)", fname, strerror(errno)); } @@ -273,7 +260,7 @@ static int io_open (lua_State *L) { LStream *p = newfile(L); const char *md = mode; /* to traverse/check mode */ luaL_argcheck(L, l_checkmode(md), 2, "invalid mode"); - p->f = trytoopen(L, filename, mode); + p->f = fopen(filename, mode); return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1; } @@ -292,8 +279,6 @@ static int io_popen (lua_State *L) { const char *mode = luaL_optstring(L, 2, "r"); LStream *p = newprefile(L); p->f = l_popen(L, filename, mode); - if (p->f == NULL && luaL_resourcetryagain(L)) /* resource failure? */ - p->f = l_popen(L, filename, mode); /* try to open again */ p->closef = &io_pclose; return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1; } @@ -302,8 +287,6 @@ static int io_popen (lua_State *L) { static int io_tmpfile (lua_State *L) { LStream *p = newfile(L); p->f = tmpfile(); - if (p->f == NULL && luaL_resourcetryagain(L)) /* resource failure? */ - p->f = tmpfile(); /* try to open again */ return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1; } diff --git a/loslib.c b/loslib.c index 1962f55f..8809e5ea 100644 --- a/loslib.c +++ b/loslib.c @@ -166,8 +166,6 @@ static int os_tmpname (lua_State *L) { char buff[LUA_TMPNAMBUFSIZE]; int err; lua_tmpnam(buff, err); - if (err && luaL_resourcetryagain(L)) /* resource failure? */ - lua_tmpnam(buff, err); /* try again */ if (err) return luaL_error(L, "unable to generate a unique filename"); lua_pushstring(L, buff); diff --git a/manual/manual.of b/manual/manual.of index d8bac5da..91ba8c46 100644 --- a/manual/manual.of +++ b/manual/manual.of @@ -5535,20 +5535,6 @@ Leaves a copy of the module on the stack. } -@APIEntry{int luaL_resourcetryagain (lua_State *L);| -@apii{0,0,m} - -Try to release resources in case of errors. -This function uses @id{errno} to check whether the last error was -related to lack of resources (e.g., not enough memory or too many -open files). -If so, the function performs a full garbage collection -to try to release resources, and then it returns 1 to signal to -the caller that it is worth trying again the failed operation. -Otherwise, it returns 0. - -} - @APIEntry{void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup);| @apii{nup,0,m}