If the input JSON to a json function that uses cache comes from an RCStr

value, then use that RCStr value in the parse rather than making a copy.

FossilOrigin-Name: 509ae9c1470dd79d320e84371e1e6662fb85fa0571df5ed8c4d946d10cdfe821

manifest

@@ -1,5 +1,5 @@
-C The\sOP_Column\sopcode\scaches\slarge\scolumn\svalues\scoming\sfrom\soverflow\spages.
-D 2023-07-27T19:39:53.698
+C If\sthe\sinput\sJSON\sto\sa\sjson\sfunction\sthat\suses\scache\scomes\sfrom\san\sRCStr\nvalue,\sthen\suse\sthat\sRCStr\svalue\sin\sthe\sparse\srather\sthan\smaking\sa\scopy.
+D 2023-07-27T20:28:29.957
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -598,7 +598,7 @@ F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
 F src/hwtime.h f9c2dfb84dce7acf95ce6d289e46f5f9d3d1afd328e53da8f8e9008e3b3caae6
 F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
 F src/insert.c 3f0a94082d978bbdd33c38fefea15346c6c6bffb70bc645a71dc0f1f87dd3276
-F src/json.c c992d2a87a6888bf16a5c7270ef523eb838cf49e6643420c3cf917124f41f97f
+F src/json.c 481dffa457276d850836953bbd2a61a00a98f8cf09c64c29c6f05ac02a84affd
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 176d6b2cb18a6ad73b133db17f6fc351c4d9a2d510deebdb76c22bde9cfd1465
 F src/main.c 512b1d45bc556edf4471a845afb7ba79e64bd5b832ab222dc195c469534cd002
@@ -643,7 +643,7 @@ F src/shell.c.in 62b58d7be1e44ec3eb729411278b079c39949e683853445323fd3f250b674a2
 F src/sqlite.h.in f999ef3642f381d69679b2516b430dbcb6c5a2a951b7f5e43dc4751b474a5774
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h da473ce2b3d0ae407a6300c4a164589b9a6bfdbec9462688a8593ff16f3bb6e4
-F src/sqliteInt.h 30d7b0d586a4d03a384dcb60088c81b6fc6f74ce85cc3a0b3242eedc3cc24dbd
+F src/sqliteInt.h 6140eb4058d995f3004ee2732fa098b884f26eb497a7fbb3a51c781ec824d14b
 F src/sqliteLimit.h 33b1c9baba578d34efe7dfdb43193b366111cdf41476b1e82699e14c11ee1fb6
 F src/status.c 160c445d7d28c984a0eae38c144f6419311ed3eace59b44ac6dafc20db4af749
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
@@ -714,7 +714,7 @@ F src/vdbeInt.h c30ef736774d876f923b42758b9210fe456104b39906e3901d21279443a17d47
 F src/vdbeapi.c dde6c4d0f87486f056b9db4d1ea185bb1d84a6839102b86e76316ba590d07cc7
 F src/vdbeaux.c 23f17d418d5b97138b7dbbd4c84d80c66dc7990653c705436c8162103b3cc9ba
 F src/vdbeblob.c 2516697b3ee8154eb8915f29466fb5d4f1ae39ee8b755ea909cefaf57ec5e2ce
-F src/vdbemem.c 33da4f30ddba2670bc1e617c3262b66aef2a8039043d4ff93e5c97974991089d
+F src/vdbemem.c aee9ac636666616494d9a395d29efc3fe9e1404a9f043db81c82560b43b78f35
 F src/vdbesort.c 0d40dca073c94e158ead752ef4225f4fee22dee84145e8c00ca2309afb489015
 F src/vdbetrace.c fe0bc29ebd4e02c8bc5c1945f1d2e6be5927ec12c06d89b03ef2a4def34bf823
 F src/vdbevtab.c 57fa8f56478e5b5cb558cb425e7878515e0a105c54f96f1d1bbf4b9433529254
@@ -2044,8 +2044,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 5739a16ad270a5aadcbb46b28c34fa6ba975422788dcbccb1a8e0d1e6ed75144
-R 84bfc9450f26b6c2dd62e6fd9e08f614
+P ab1edcc7fedcf27922d5db4bc1bc673b1495ca9c66eb6debdda7b7776c068888
+R bc4f27407c20176b7c3faf6538598e39
 U drh
-Z 46d23d17a391909f5bac31a5a474dfd0
+Z 559a7376c279a69632a349e06eee6ec2
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-ab1edcc7fedcf27922d5db4bc1bc673b1495ca9c66eb6debdda7b7776c068888
+509ae9c1470dd79d320e84371e1e6662fb85fa0571df5ed8c4d946d10cdfe821

src/json.c

@@ -174,6 +174,7 @@ struct JsonParse {
   u16 iDepth;        /* Nesting depth */
   u8 nErr;           /* Number of errors seen */
   u8 oom;            /* Set to true if out of memory */
+  u8 bJsonIsRCStr;   /* True if zJson is an RCStr */
   u8 hasNonstd;      /* True if input uses non-standard features like JSON5 */
   u8 useMod;         /* Actually use the edits contain inside aNode */
   u8 hasMod;         /* aNode contains edits from the original zJson */
@@ -619,6 +620,11 @@ static void jsonParseReset(JsonParse *pParse){
     sqlite3_free(pParse->aUp);
     pParse->aUp = 0;
   }
+  if( pParse->bJsonIsRCStr ){
+    sqlite3RCStrUnref(pParse->zJson);
+    pParse->zJson = 0;
+    pParse->bJsonIsRCStr = 0;
+  }
   if( pParse->zAlt ){
     sqlite3RCStrUnref(pParse->zAlt);
     pParse->zAlt = 0;
@@ -1884,6 +1890,8 @@ static JsonParse *jsonParseCached(
   int iMinKey = 0;
   u32 iMinHold = 0xffffffff;
   u32 iMaxHold = 0;
+  int bJsonRCStr;
+  int rc;
 
   if( zJson==0 ) return 0;
   for(iKey=0; iKey<JSON_CACHE_SZ; iKey++){
@@ -1895,7 +1903,7 @@ static JsonParse *jsonParseCached(
     if( pMatch==0
      && p->nJson==nJson
      && (p->hasMod==0 || bUnedited==0)
-     && memcmp(p->zJson,zJson,nJson)==0
+     && (p->zJson==zJson || memcmp(p->zJson,zJson,nJson)==0)
     ){
       p->nErr = 0;
       p->useMod = 0;
@@ -1930,16 +1938,22 @@ static JsonParse *jsonParseCached(
   /* The input JSON was not found anywhere in the cache.  We will need
   ** to parse it ourselves and generate a new JsonParse object.
   */
-  p = sqlite3_malloc64( sizeof(*p) + nJson + 1 );
+  bJsonRCStr = sqlite3ValueIsOfClass(pJson,(void(*)(void*))sqlite3RCStrUnref);
+  p = sqlite3_malloc64( sizeof(*p) + (bJsonRCStr ? 0 : nJson+1) );
   if( p==0 ){
     sqlite3_result_error_nomem(pCtx);
     return 0;
   }
   memset(p, 0, sizeof(*p));
-  p->zJson = (char*)&p[1];
-  memcpy(p->zJson, zJson, nJson);
-  p->zJson[nJson] = 0;
-  if( jsonParse(p, pErrCtx, p->zJson) ){
+  if( bJsonRCStr ){
+    p->zJson = sqlite3RCStrRef(zJson);
+  }else{
+    p->zJson = (char*)&p[1];
+    memcpy(p->zJson, zJson, nJson+1);
+  }
+  rc = jsonParse(p, pErrCtx, p->zJson);
+  p->bJsonIsRCStr = bJsonRCStr;
+  if( rc ){
     if( pErrCtx==0 ){
       p->nErr = 1;
       assert( p->nJPRef==1 ); /* Caller will own the new JsonParse object p */

src/sqliteInt.h

@@ -5200,6 +5200,7 @@ void sqlite3FileSuffix3(const char*, char*);
 u8 sqlite3GetBoolean(const char *z,u8);
 
 const void *sqlite3ValueText(sqlite3_value*, u8);
+int sqlite3ValueIsOfClass(const sqlite3_value*, void(*)(void*));
 int sqlite3ValueBytes(sqlite3_value*, u8);
 void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
                         void(*)(void*));

src/vdbemem.c

@@ -1368,6 +1368,24 @@ const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){
   return valueToText(pVal, enc);
 }
 
+/* Return true if sqlit3_value object pVal is a string or blob value
+** that uses the destructor specified in the second argument.
+**
+** TODO:  Maybe someday promote this interface into a published API so
+** that third-party extensions can get access to it?
+*/
+int sqlite3ValueIsOfClass(const sqlite3_value *pVal, void(*xFree)(void*)){
+  if( ALWAYS(pVal!=0)
+   && (pVal->flags & (MEM_Str|MEM_Blob))!=0
+   && (pVal->flags & MEM_Dyn)!=0
+   && pVal->xDel==xFree
+  ){
+    return 1;
+  }else{
+    return 0;
+  }
+}
+
 /*
 ** Create a new sqlite3_value object.
 */