Parse PGN tags without allocating memory

In WinBoard malloc/free did not seem to work when preparing the game list,
leading to a huge memory list when ParsePGNTag was used. The added code
parses the required tags in an alternative way as a work-around.

diff --git a/backend.c b/backend.c
index 804da7d..b313fa5 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -11100,8 +11100,24 @@ int GameContainsPosition(FILE *f, ListGame *lg)
        switch(next) {
            case PGNTag:
                if(plyNr) return -1; // after we have seen moves, any tags will be start of next game
-               ParsePGNTag(yy_text, &dummyInfo);
-           if(dummyInfo.fen) ParseFEN(boards[scratch], &btm, dummyInfo.fen), free(dummyInfo.fen), dummyInfo.fen = NULL;
+#if 0
+               ParsePGNTag(yy_text, &dummyInfo); // this has a bad memory leak...
+               if(dummyInfo.fen) ParseFEN(boards[scratch], &btm, dummyInfo.fen), free(dummyInfo.fen), dummyInfo.fen = NULL;
+#else
+               // do it ourselves avoiding malloc
+               { char *p = yy_text+1, *q;
+                 while(!isdigit(*p) && !isalpha(*p)) p++;
+                 q  = p; while(*p != ' ' && *p != '\t' && *p != '\n') p++;
+                 *p = NULLCHAR;
+                 if(!StrCaseCmp(q, "Date") && (p = strchr(p+1, '"'))) { if(atoi(p+1) < appData.dateThreshold) return -1; } else
+                 if(!StrCaseCmp(q, "Variant")  &&  (p = strchr(p+1, '"'))) dummyInfo.variant = StringToVariant(p+1); else
+                 if(!StrCaseCmp(q, "WhiteElo")  && (p = strchr(p+1, '"'))) dummyInfo.whiteRating = atoi(p+1); else
+                 if(!StrCaseCmp(q, "BlackElo")  && (p = strchr(p+1, '"'))) dummyInfo.blackRating = atoi(p+1); else
+                 if(!StrCaseCmp(q, "WhiteUSCF") && (p = strchr(p+1, '"'))) dummyInfo.whiteRating = atoi(p+1); else
+                 if(!StrCaseCmp(q, "BlackUSCF") && (p = strchr(p+1, '"'))) dummyInfo.blackRating = atoi(p+1); else
+                 if(!StrCaseCmp(q, "FEN")  && (p = strchr(p+1, '"'))) ParseFEN(boards[scratch], &btm, p+1);
+               }
+#endif
            default:
                continue;