4 files changed, 17 insertions, 8 deletions

diff --git a/history.c b/history.c
index f2a00b4..2ba0400 100644
--- a/history.c
+++ b/history.c
@@ -119,7 +119,8 @@ unshiftHist(Hist *hist, char *ptr)
 {
     HistItem *item;
 
-    if (hist == NULL || hist->list == NULL)
+    if (hist == NULL || hist->list == NULL ||
+	hist->list->nitem >= HIST_LIST_MAX)
 	return NULL;
     item = (HistItem *)newListItem((void *)allocStr(ptr, -1),
 				   (ListItem *)hist->list->first, NULL);
@@ -137,7 +138,8 @@ pushHist(Hist *hist, char *ptr)
 {
     HistItem *item;
 
-    if (hist == NULL || hist->list == NULL)
+    if (hist == NULL || hist->list == NULL ||
+	hist->list->nitem >= HIST_LIST_MAX)
 	return NULL;
     item = (HistItem *)newListItem((void *)allocStr(ptr, -1),
 				   NULL, (ListItem *)hist->list->last);
@@ -157,7 +159,8 @@ pushHashHist(Hist *hist, char *ptr)
 {
     HistItem *item;
 
-    if (hist == NULL || hist->list == NULL)
+    if (hist == NULL || hist->list == NULL ||
+	hist->list->nitem >= HIST_LIST_MAX)
 	return NULL;
     item = getHashHist(hist, ptr);
     if (item) {
diff --git a/history.h b/history.h
index 4c41099..e2b3bf2 100644
--- a/history.h
+++ b/history.h
@@ -5,6 +5,7 @@
 #include "textlist.h"
 #include "hash.h"
 
+#define HIST_LIST_MAX GENERAL_LIST_MAX
 #define HIST_HASH_SIZE 127
 
 typedef ListItem HistItem;
diff --git a/textlist.c b/textlist.c
index fda46eb..2026fc5 100644
--- a/textlist.c
+++ b/textlist.c
@@ -30,7 +30,7 @@ void
 pushValue(GeneralList *tl, void *s)
 {
     ListItem *it;
-    if (s == NULL)
+    if (s == NULL || tl == NULL || tl->nitem >= GENERAL_LIST_MAX)
 	return;
     it = newListItem(s, NULL, tl->last);
     if (tl->first == NULL) {
@@ -99,6 +99,9 @@ appendGeneralList(GeneralList *tl, GeneralList *tl2)
     if (tl && tl2) {
 	if (tl2->first) {
 	    if (tl->last) {
+		if (tl->nitem + tl2->nitem > GENERAL_LIST_MAX) {
+		    return tl;
+		}
 		tl->last->next = tl2->first;
 		tl2->first->prev = tl->last;
 		tl->last = tl2->last;
diff --git a/textlist.h b/textlist.h
index f28b199..654adfb 100644
--- a/textlist.h
+++ b/textlist.h
@@ -2,6 +2,8 @@
 #ifndef TEXTLIST_H
 #define TEXTLIST_H
 #include "Str.h"
+#include <limits.h>
+#define GENERAL_LIST_MAX (INT_MAX / 32)
 
 /* General doubly linked list */
 
@@ -14,7 +16,7 @@ typedef struct _listitem {
 typedef struct _generallist {
     ListItem *first;
     ListItem *last;
-    short nitem;
+    int nitem;
 } GeneralList;
 
 extern ListItem *newListItem(void *s, ListItem *n, ListItem *p);
@@ -36,7 +38,7 @@ typedef struct _textlistitem {
 typedef struct _textlist {
     TextListItem *first;
     TextListItem *last;
-    short nitem;
+    int nitem;
 } TextList;
 
 #define newTextList() ((TextList *)newGeneralList())
@@ -50,7 +52,7 @@ typedef struct _textlist {
 
 typedef struct _TextLine {
     Str line;
-    short pos;
+    int pos;
 } TextLine;
 
 typedef struct _textlinelistitem {
@@ -62,7 +64,7 @@ typedef struct _textlinelistitem {
 typedef struct _textlinelist {
     TextLineListItem *first;
     TextLineListItem *last;
-    short nitem;
+    int nitem;
 } TextLineList;
 
 extern TextLine *newTextLine(Str line, int pos);