5 files changed, 71 insertions, 50 deletions

diff --git a/lauxlib.c b/lauxlib.c
index a8f2cc2e..53b8c9bb 100644
--- a/lauxlib.c
+++ b/lauxlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lauxlib.c,v 1.294 2018/02/27 18:47:32 roberto Exp roberto $
+** $Id: lauxlib.c $
 ** Auxiliary functions for building Lua libraries
 ** See Copyright Notice in lua.h
 */
@@ -292,6 +292,50 @@ 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 */
+
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
 ** Userdata's metatable manipulation
 ** =======================================================
 */
diff --git a/lauxlib.h b/lauxlib.h
index 9f91f6a6..cd4d01e5 100644
--- a/lauxlib.h
+++ b/lauxlib.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lauxlib.h,v 1.133 2017/06/27 18:32:49 roberto Exp roberto $
+** $Id: lauxlib.h $
 ** Auxiliary functions for building Lua libraries
 ** See Copyright Notice in lua.h
 */
@@ -77,6 +77,9 @@ 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)
 #define LUA_REFNIL      (-1)
diff --git a/liolib.c b/liolib.c
index 75e10ded..21305b8c 100644
--- a/liolib.c
+++ b/liolib.c
@@ -133,50 +133,6 @@ static int l_checkmode (const char *mode) {
 /* }====================================================== */
 
 
-/*
-** {======================================================
-** '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.
-** =======================================================
-*/
-
-static int 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 */
-
-}
-
-/* }====================================================== */
-
-
 
 #define IO_PREFIX       "_IO_"
 #define IOPREF_LEN      (sizeof(IO_PREFIX)/sizeof(char) - 1)
@@ -292,12 +248,12 @@ static LStream *newfile (lua_State *L) {
 
 /*
 ** Equivalent to 'fopen', but if it fails due to a lack of resources
-** (see 'resourcetryagain'), do an "emergency" garbage collection to try
-** to close some files and then tries to open the file again.
+** (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 && resourcetryagain(L))  /* resource failure? */
+  if (f == NULL && luaL_resourcetryagain(L))  /* resource failure? */
     f = fopen(path, mode);  /* try to open again */
   return f;
 }
@@ -336,7 +292,7 @@ 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 && resourcetryagain(L))  /* resource failure? */
+  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;
@@ -346,6 +302,8 @@ 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 8809e5ea..1962f55f 100644
--- a/loslib.c
+++ b/loslib.c
@@ -166,6 +166,8 @@ 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 659daa55..5a8b1b2c 100644
--- a/manual/manual.of
+++ b/manual/manual.of
@@ -5538,6 +5538,20 @@ 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}