better treatment for arbitrary limits

8 files changed, 56 insertions, 34 deletions

diff --git a/lapi.c b/lapi.c
index 45d961d2..50871e0c 100644
--- a/lapi.c
+++ b/lapi.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lapi.c,v 1.44 1999/05/11 20:08:20 roberto Exp roberto $
+** $Id: lapi.c,v 1.45 1999/05/14 12:24:20 roberto Exp roberto $
 ** Lua API
 ** See Copyright Notice in lua.h
 */
@@ -632,7 +632,7 @@ char *lua_getobjname (lua_Object o, char **name)
 
 
 #ifndef MAX_C_BLOCKS
-#define MAX_C_BLOCKS    1000
+#define MAX_C_BLOCKS    1000  /* arbitrary limit */
 #endif
 
 
diff --git a/lbuiltin.c b/lbuiltin.c
index 077bcc46..6cf915ca 100644
--- a/lbuiltin.c
+++ b/lbuiltin.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lbuiltin.c,v 1.57 1999/05/24 17:53:49 roberto Exp roberto $
+** $Id: lbuiltin.c,v 1.58 1999/05/27 20:21:03 roberto Exp roberto $
 ** Built-in functions
 ** See Copyright Notice in lua.h
 */
@@ -111,7 +111,10 @@ static void error_message (void) {
 ** model but changing "fputs" to put the strings at a proper place
 ** (a console window or a log file, for instance).
 */
-#define MAXPRINT        40
+#ifndef MAXPRINT
+#define MAXPRINT        40  /* arbitrary limit */
+#endif
+
 static void luaB_print (void) {
   lua_Object args[MAXPRINT];
   lua_Object obj;
diff --git a/ldo.c b/ldo.c
index 2216d97a..c6c418a1 100644
--- a/ldo.c
+++ b/ldo.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldo.c,v 1.42 1999/05/10 13:54:01 roberto Exp roberto $
+** $Id: ldo.c,v 1.43 1999/05/24 17:53:03 roberto Exp roberto $
 ** Stack and Call structure of Lua
 ** See Copyright Notice in lua.h
 */
@@ -29,7 +29,7 @@
 
 
 #ifndef STACK_LIMIT
-#define STACK_LIMIT     6000
+#define STACK_LIMIT     6000  /* arbitrary limit */
 #endif
 
 
diff --git a/llex.c b/llex.c
index 3734b003..4368fe66 100644
--- a/llex.c
+++ b/llex.c
@@ -1,5 +1,5 @@
 /*
-** $Id: llex.c,v 1.34 1999/03/25 21:05:05 roberto Exp roberto $
+** $Id: llex.c,v 1.35 1999/05/14 12:24:04 roberto Exp roberto $
 ** Lexical Analyzer
 ** See Copyright Notice in lua.h
 */
@@ -106,7 +106,9 @@ void luaX_setinput (LexState *LS, ZIO *z)
 ** =======================================================
 */
 
-#define PRAGMASIZE      80
+#ifndef PRAGMASIZE
+#define PRAGMASIZE      80  /* arbitrary limit */
+#endif
 
 static void skipspace (LexState *LS) {
   while (LS->current == ' ' || LS->current == '\t' || LS->current == '\r')
diff --git a/llex.h b/llex.h
index 84c0ee99..058e3ee0 100644
--- a/llex.h
+++ b/llex.h
@@ -1,5 +1,5 @@
 /*
-** $Id: llex.h,v 1.10 1998/07/24 18:02:38 roberto Exp roberto $
+** $Id: llex.h,v 1.11 1999/02/25 19:13:56 roberto Exp roberto $
 ** Lexical Analyzer
 ** See Copyright Notice in lua.h
 */
@@ -25,7 +25,9 @@ enum RESERVED {
   NAME, CONC, DOTS, EQ, GE, LE, NE, NUMBER, STRING, EOS};
 
 
-#define MAX_IFS 5
+#ifndef MAX_IFS
+#define MAX_IFS 5  /* arbitrary limit */
+#endif
 
 /* "ifstate" keeps the state of each nested $if the lexical is dealing with. */
 
diff --git a/lopcodes.h b/lopcodes.h
index 6ac94619..f9633cac 100644
--- a/lopcodes.h
+++ b/lopcodes.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lopcodes.h,v 1.31 1999/03/05 21:16:07 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.32 1999/03/10 14:09:45 roberto Exp roberto $
 ** Opcodes for Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -113,7 +113,7 @@ CHECKSTACK /*	b  (assert #temporaries == b; only for internal debuging!) */
 #define RFIELDS_PER_FLUSH 32    /* records (SETMAP) */
 #define LFIELDS_PER_FLUSH 64    /* FPF - lists (SETLIST) */
 
-#define ZEROVARARG      64
+#define ZEROVARARG      128
 
 
 /* maximum value of an arg of 3 bytes; must fit in an "int" */
diff --git a/lparser.c b/lparser.c
index f44a9563..8fc3df90 100644
--- a/lparser.c
+++ b/lparser.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.c,v 1.35 1999/06/16 13:22:04 roberto Exp roberto $
+** $Id: lparser.c,v 1.36 1999/06/16 13:35:01 roberto Exp roberto $
 ** LL(1) Parser and code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -22,26 +22,32 @@
 #include "lzio.h"
 
 
-/* for limit numbers in error messages */
-#define MES_LIM(x)      "(limit=" x ")"
-
 
 /* size of a "normal" jump instruction: OpCode + 1 byte */
 #define JMPSIZE 2
 
 /* maximum number of local variables */
-#define MAXLOCALS 200
-#define SMAXLOCALS "200"
+#ifndef MAXLOCALS
+#define MAXLOCALS 200  /* arbitrary limit (<256) */
+#endif
 
 
 /* maximum number of upvalues */
-#define MAXUPVALUES 32
-#define SMAXUPVALUES "32"
+#ifndef MAXUPVALUES
+#define MAXUPVALUES 32  /* arbitrary limit (<256) */
+#endif
 
 
 /* maximum number of variables in the left side of an assignment */
-#define MAXVARSLH       100
-#define SMAXVARSLH      "100"
+#ifndef MAXVARSLH
+#define MAXVARSLH       100  /* arbitrary limit (<255) */
+#endif
+
+
+/* maximum number of parameters in a function */
+#ifndef MAXPARAMS
+#define MAXPARAMS       100  /* arbitrary limit (<ZEROVARARG) */
+#endif
 
 
 /*
@@ -136,6 +142,15 @@ static void var_or_func_tail (LexState *ls, vardesc *v);
 
 
 
+static void checklimit (LexState *ls, int val, int limit, char *msg) {
+  if (val > limit) {
+    char buff[100];
+    sprintf(buff, "too many %s (limit=%d)", msg, limit);
+    luaX_error(ls, buff);
+  }
+}
+
+
 static void check_pc (FuncState *fs, int n) {
   luaM_growvector(fs->f->code, fs->pc, n, Byte, codeEM, MAX_INT);
 }
@@ -310,8 +325,7 @@ static void luaI_unregisterlocalvar (FuncState *fs, int line) {
 
 static void store_localvar (LexState *ls, TaggedString *name, int n) {
   FuncState *fs = ls->fs;
-  if (fs->nlocalvar+n >= MAXLOCALS)
-    luaX_error(ls, "too many local variables " MES_LIM(SMAXLOCALS));
+  checklimit(ls, fs->nlocalvar+n+1, MAXLOCALS, "local variables");
   fs->localvar[fs->nlocalvar+n] = name;
   luaI_registerlocalvar(fs, name, ls->linenumber);
 }
@@ -369,9 +383,8 @@ static int indexupvalue (LexState *ls, TaggedString *n) {
       return i;
   }
   /* new one */
-  if (++(fs->nupvalues) > MAXUPVALUES)
-    luaX_error(ls, "too many upvalues in a single function "
-                   MES_LIM(SMAXUPVALUES));
+  ++(fs->nupvalues);
+  checklimit(ls, fs->nupvalues, MAXUPVALUES, "upvalues");
   fs->upvalues[i] = v;  /* i = fs->nupvalues - 1 */
   return i;
 }
@@ -439,6 +452,7 @@ static void adjust_mult_assign (LexState *ls, int nvars, listdesc *d) {
 static void code_args (LexState *ls, int nparams, int dots) {
   FuncState *fs = ls->fs;
   fs->nlocalvar += nparams;  /* "self" may already be there */
+  checklimit(ls, fs->nlocalvar, MAXPARAMS, "parameters");
   nparams = fs->nlocalvar;
   if (!dots) {
     fs->f->code[1] = (Byte)nparams;  /* fill-in arg information */
@@ -917,7 +931,7 @@ static int priority [POW+1] =  {5, 5, 1, 1, 1, 1, 1, 1, 2, 3, 3, 4, 4, 6};
 static OpCode opcodes [POW+1] = {NOTOP, MINUSOP, EQOP, NEQOP, GTOP, LTOP,
   LEOP, GEOP, CONCOP, ADDOP, SUBOP, MULTOP, DIVOP, POWOP};
 
-#define MAXOPS  20  /* op's stack size */
+#define MAXOPS  20  /* op's stack size (arbitrary limit) */
 
 typedef struct stack_op {
   int ops[MAXOPS];
@@ -1226,9 +1240,7 @@ static void decinit (LexState *ls, listdesc *d) {
 
 static int assignment (LexState *ls, vardesc *v, int nvars) {
   int left = 0;
-  if (nvars > MAXVARSLH)
-    luaX_error(ls, "too many variables in a multiple assignment "
-                   MES_LIM(SMAXVARSLH));
+  checklimit(ls, nvars, MAXVARSLH, "variables in a multiple assignment");
   unloaddot(ls, v);
   if (ls->token == ',') {  /* assignment -> ',' NAME assignment */
     vardesc nv;
diff --git a/lstrlib.c b/lstrlib.c
index d03612af..b915cad9 100644
--- a/lstrlib.c
+++ b/lstrlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lstrlib.c,v 1.30 1999/05/05 19:22:26 roberto Exp roberto $
+** $Id: lstrlib.c,v 1.31 1999/05/14 12:24:04 roberto Exp roberto $
 ** Standard library for strings and pattern-matching
 ** See Copyright Notice in lua.h
 */
@@ -117,7 +117,10 @@ static void str_char (void) {
 ** =======================================================
 */
 
-#define MAX_CAPT 32
+#ifndef MAX_CAPT
+#define MAX_CAPT 32  /* arbitrary limit */
+#endif
+
 
 struct Capture {
   char *src_end;  /* end ('\0') of source string */
@@ -499,7 +502,7 @@ static void luaI_addquoted (int arg) {
 }
 
 /* maximum size of each format specification (such as '%-099.99d') */
-#define MAX_FORMAT 20
+#define MAX_FORMAT 20  /* arbitrary limit */
 
 static void str_format (void) {
   int arg = 1;