diff options
Diffstat (limited to 'src/json.c')
| -rw-r--r-- | src/json.c | 992 |
1 files changed, 498 insertions, 494 deletions
diff --git a/src/json.c b/src/json.c index c7c6becbd..9ea085753 100644 --- a/src/json.c +++ b/src/json.c @@ -1779,6 +1779,33 @@ json_parse_restart: } /* End switch(z[i]) */ } +/* Mark node i of pParse as being a child of iParent. Call recursively +** to fill in all the descendants of node i. +*/ +static void jsonParseFillInParentage(JsonParse *pParse, u32 i, u32 iParent){ + JsonNode *pNode = &pParse->aNode[i]; + u32 j; + pParse->aUp[i] = iParent; + switch( pNode->eType ){ + case JSON_ARRAY: { + for(j=1; j<=pNode->n; j += jsonNodeSize(pNode+j)){ + jsonParseFillInParentage(pParse, i+j, i); + } + break; + } + case JSON_OBJECT: { + for(j=1; j<=pNode->n; j += jsonNodeSize(pNode+j+1)+1){ + pParse->aUp[i+j] = i; + jsonParseFillInParentage(pParse, i+j+1, i); + } + break; + } + default: { + break; + } + } +} + /* ** Parse a complete JSON string. Return 0 on success or non-zero if there ** are any errors. If an error occurs, free all memory held by pParse, @@ -1822,6 +1849,477 @@ static int jsonParse( } /* +** Compute the parentage of all nodes in a completed parse. +*/ +static int jsonParseFindParents(JsonParse *pParse){ + u32 *aUp; + assert( pParse->aUp==0 ); + aUp = pParse->aUp = sqlite3_malloc64( sizeof(u32)*pParse->nNode ); + if( aUp==0 ){ + pParse->oom = 1; + return SQLITE_NOMEM; + } + jsonParseFillInParentage(pParse, 0, 0); + return SQLITE_OK; +} + +/* +** Magic number used for the JSON parse cache in sqlite3_get_auxdata() +*/ +#define JSON_CACHE_ID (-429938) /* First cache entry */ +#define JSON_CACHE_SZ 4 /* Max number of cache entries */ + +/* +** Obtain a complete parse of the JSON found in the pJson argument +** +** Use the sqlite3_get_auxdata() cache to find a preexisting parse +** if it is available. If the cache is not available or if it +** is no longer valid, parse the JSON again and return the new parse. +** Also register the new parse so that it will be available for +** future sqlite3_get_auxdata() calls. +** +** If an error occurs and pErrCtx!=0 then report the error on pErrCtx +** and return NULL. +** +** The returned pointer (if it is not NULL) is owned by the cache in +** most cases, not the caller. The caller does NOT need to invoke +** jsonParseFree(), in most cases. +** +** Except, if an error occurs and pErrCtx==0 then return the JsonParse +** object with JsonParse.nErr non-zero and the caller will own the JsonParse +** object. In that case, it will be the responsibility of the caller to +** invoke jsonParseFree(). To summarize: +** +** pErrCtx!=0 || p->nErr==0 ==> Return value p is owned by the +** cache. Call does not need to +** free it. +** +** pErrCtx==0 && p->nErr!=0 ==> Return value is owned by the caller +** and so the caller must free it. +*/ +static JsonParse *jsonParseCached( + sqlite3_context *pCtx, /* Context to use for cache search */ + sqlite3_value *pJson, /* Function param containing JSON text */ + sqlite3_context *pErrCtx, /* Write parse errors here if not NULL */ + int bUnedited /* No prior edits allowed */ +){ + char *zJson = (char*)sqlite3_value_text(pJson); + int nJson = sqlite3_value_bytes(pJson); + JsonParse *p; + JsonParse *pMatch = 0; + int iKey; + int iMinKey = 0; + u32 iMinHold = 0xffffffff; + u32 iMaxHold = 0; + int bJsonRCStr; + + if( zJson==0 ) return 0; + for(iKey=0; iKey<JSON_CACHE_SZ; iKey++){ + p = (JsonParse*)sqlite3_get_auxdata(pCtx, JSON_CACHE_ID+iKey); + if( p==0 ){ + iMinKey = iKey; + break; + } + if( pMatch==0 + && p->nJson==nJson + && (p->hasMod==0 || bUnedited==0) + && (p->zJson==zJson || memcmp(p->zJson,zJson,nJson)==0) + ){ + p->nErr = 0; + p->useMod = 0; + pMatch = p; + }else + if( pMatch==0 + && p->zAlt!=0 + && bUnedited==0 + && p->nAlt==nJson + && memcmp(p->zAlt, zJson, nJson)==0 + ){ + p->nErr = 0; + p->useMod = 1; + pMatch = p; + }else if( p->iHold<iMinHold ){ + iMinHold = p->iHold; + iMinKey = iKey; + } + if( p->iHold>iMaxHold ){ + iMaxHold = p->iHold; + } + } + if( pMatch ){ + /* The input JSON text was found in the cache. Use the preexisting + ** parse of this JSON */ + pMatch->nErr = 0; + pMatch->iHold = iMaxHold+1; + assert( pMatch->nJPRef>0 ); /* pMatch is owned by the cache */ + return pMatch; + } + + /* The input JSON was not found anywhere in the cache. We will need + ** to parse it ourselves and generate a new JsonParse object. + */ + 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)); + if( bJsonRCStr ){ + p->zJson = sqlite3RCStrRef(zJson); + p->bJsonIsRCStr = 1; + }else{ + p->zJson = (char*)&p[1]; + memcpy(p->zJson, zJson, nJson+1); + } + p->nJPRef = 1; + if( jsonParse(p, pErrCtx) ){ + if( pErrCtx==0 ){ + p->nErr = 1; + assert( p->nJPRef==1 ); /* Caller will own the new JsonParse object p */ + return p; + } + jsonParseFree(p); + return 0; + } + p->nJson = nJson; + p->iHold = iMaxHold+1; + /* Transfer ownership of the new JsonParse to the cache */ + sqlite3_set_auxdata(pCtx, JSON_CACHE_ID+iMinKey, p, + (void(*)(void*))jsonParseFree); + return (JsonParse*)sqlite3_get_auxdata(pCtx, JSON_CACHE_ID+iMinKey); +} + +/* +** Compare the OBJECT label at pNode against zKey,nKey. Return true on +** a match. +*/ +static int jsonLabelCompare(const JsonNode *pNode, const char *zKey, u32 nKey){ + assert( pNode->eU==1 ); + if( pNode->jnFlags & JNODE_RAW ){ + if( pNode->n!=nKey ) return 0; + return strncmp(pNode->u.zJContent, zKey, nKey)==0; + }else{ + if( pNode->n!=nKey+2 ) return 0; + return strncmp(pNode->u.zJContent+1, zKey, nKey)==0; + } +} +static int jsonSameLabel(const JsonNode *p1, const JsonNode *p2){ + if( p1->jnFlags & JNODE_RAW ){ + return jsonLabelCompare(p2, p1->u.zJContent, p1->n); + }else if( p2->jnFlags & JNODE_RAW ){ + return jsonLabelCompare(p1, p2->u.zJContent, p2->n); + }else{ + return p1->n==p2->n && strncmp(p1->u.zJContent,p2->u.zJContent,p1->n)==0; + } +} + +/* forward declaration */ +static JsonNode *jsonLookupAppend(JsonParse*,const char*,int*,const char**); + +/* +** Search along zPath to find the node specified. Return a pointer +** to that node, or NULL if zPath is malformed or if there is no such +** node. +** +** If pApnd!=0, then try to append new nodes to complete zPath if it is +** possible to do so and if no existing node corresponds to zPath. If +** new nodes are appended *pApnd is set to 1. +*/ +static JsonNode *jsonLookupStep( + JsonParse *pParse, /* The JSON to search */ + u32 iRoot, /* Begin the search at this node */ + const char *zPath, /* The path to search */ + int *pApnd, /* Append nodes to complete path if not NULL */ + const char **pzErr /* Make *pzErr point to any syntax error in zPath */ +){ + u32 i, j, nKey; + const char *zKey; + JsonNode *pRoot; + if( pParse->oom ) return 0; + pRoot = &pParse->aNode[iRoot]; + if( pRoot->jnFlags & (JNODE_REPLACE|JNODE_REMOVE) && pParse->useMod ){ + while( (pRoot->jnFlags & JNODE_REPLACE)!=0 ){ + u32 idx = (u32)(pRoot - pParse->aNode); + i = pParse->iSubst; + while( 1 /*exit-by-break*/ ){ + assert( i<pParse->nNode ); + assert( pParse->aNode[i].eType==JSON_SUBST ); + assert( pParse->aNode[i].eU==4 ); + assert( pParse->aNode[i].u.iPrev<i ); + if( pParse->aNode[i].n==idx ){ + pRoot = &pParse->aNode[i+1]; + iRoot = i+1; + break; + } + i = pParse->aNode[i].u.iPrev; + } + } + if( pRoot->jnFlags & JNODE_REMOVE ){ + return 0; + } + } + if( zPath[0]==0 ) return pRoot; + if( zPath[0]=='.' ){ + if( pRoot->eType!=JSON_OBJECT ) return 0; + zPath++; + if( zPath[0]=='"' ){ + zKey = zPath + 1; + for(i=1; zPath[i] && zPath[i]!='"'; i++){} + nKey = i-1; + if( zPath[i] ){ + i++; + }else{ + *pzErr = zPath; + return 0; + } + testcase( nKey==0 ); + }else{ + zKey = zPath; + for(i=0; zPath[i] && zPath[i]!='.' && zPath[i]!='['; i++){} + nKey = i; + if( nKey==0 ){ + *pzErr = zPath; + return 0; + } + } + j = 1; + for(;;){ + while( j<=pRoot->n ){ + if( jsonLabelCompare(pRoot+j, zKey, nKey) ){ + return jsonLookupStep(pParse, iRoot+j+1, &zPath[i], pApnd, pzErr); + } + j++; + j += jsonNodeSize(&pRoot[j]); + } + if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break; + if( pParse->useMod==0 ) break; + assert( pRoot->eU==2 ); + iRoot = pRoot->u.iAppend; + pRoot = &pParse->aNode[iRoot]; + j = 1; + } + if( pApnd ){ + u32 iStart, iLabel; + JsonNode *pNode; + assert( pParse->useMod ); + iStart = jsonParseAddNode(pParse, JSON_OBJECT, 2, 0); + iLabel = jsonParseAddNode(pParse, JSON_STRING, nKey, zKey); + zPath += i; + pNode = jsonLookupAppend(pParse, zPath, pApnd, pzErr); + if( pParse->oom ) return 0; + if( pNode ){ + pRoot = &pParse->aNode[iRoot]; + assert( pRoot->eU==0 ); + pRoot->u.iAppend = iStart; + pRoot->jnFlags |= JNODE_APPEND; + VVA( pRoot->eU = 2 ); + pParse->aNode[iLabel].jnFlags |= JNODE_RAW; + } + return pNode; + } + }else if( zPath[0]=='[' ){ + i = 0; + j = 1; + while( sqlite3Isdigit(zPath[j]) ){ + i = i*10 + zPath[j] - '0'; + j++; + } + if( j<2 || zPath[j]!=']' ){ + if( zPath[1]=='#' ){ + JsonNode *pBase = pRoot; + int iBase = iRoot; + if( pRoot->eType!=JSON_ARRAY ) return 0; + for(;;){ + while( j<=pBase->n ){ + if( (pBase[j].jnFlags & JNODE_REMOVE)==0 || pParse->useMod==0 ) i++; + j += jsonNodeSize(&pBase[j]); + } + if( (pBase->jnFlags & JNODE_APPEND)==0 ) break; + if( pParse->useMod==0 ) break; + assert( pBase->eU==2 ); + iBase = pBase->u.iAppend; + pBase = &pParse->aNode[iBase]; + j = 1; + } + j = 2; + if( zPath[2]=='-' && sqlite3Isdigit(zPath[3]) ){ + unsigned int x = 0; + j = 3; + do{ + x = x*10 + zPath[j] - '0'; + j++; + }while( sqlite3Isdigit(zPath[j]) ); + if( x>i ) return 0; + i -= x; + } + if( zPath[j]!=']' ){ + *pzErr = zPath; + return 0; + } + }else{ + *pzErr = zPath; + return 0; + } + } + if( pRoot->eType!=JSON_ARRAY ) return 0; + zPath += j + 1; + j = 1; + for(;;){ + while( j<=pRoot->n + && (i>0 || ((pRoot[j].jnFlags & JNODE_REMOVE)!=0 && pParse->useMod)) + ){ + if( (pRoot[j].jnFlags & JNODE_REMOVE)==0 || pParse->useMod==0 ) i--; + j += jsonNodeSize(&pRoot[j]); + } + if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break; + if( pParse->useMod==0 ) break; + assert( pRoot->eU==2 ); + iRoot = pRoot->u.iAppend; + pRoot = &pParse->aNode[iRoot]; + j = 1; + } + if( j<=pRoot->n ){ + return jsonLookupStep(pParse, iRoot+j, zPath, pApnd, pzErr); + } + if( i==0 && pApnd ){ + u32 iStart; + JsonNode *pNode; + assert( pParse->useMod ); + iStart = jsonParseAddNode(pParse, JSON_ARRAY, 1, 0); + pNode = jsonLookupAppend(pParse, zPath, pApnd, pzErr); + if( pParse->oom ) return 0; + if( pNode ){ + pRoot = &pParse->aNode[iRoot]; + assert( pRoot->eU==0 ); + pRoot->u.iAppend = iStart; + pRoot->jnFlags |= JNODE_APPEND; + VVA( pRoot->eU = 2 ); + } + return pNode; + } + }else{ + *pzErr = zPath; + } + return 0; +} + +/* +** Append content to pParse that will complete zPath. Return a pointer +** to the inserted node, or return NULL if the append fails. +*/ +static JsonNode *jsonLookupAppend( + JsonParse *pParse, /* Append content to the JSON parse */ + const char *zPath, /* Description of content to append */ + int *pApnd, /* Set this flag to 1 */ + const char **pzErr /* Make this point to any syntax error */ +){ + *pApnd = 1; + if( zPath[0]==0 ){ + jsonParseAddNode(pParse, JSON_NULL, 0, 0); + return pParse->oom ? 0 : &pParse->aNode[pParse->nNode-1]; + } + if( zPath[0]=='.' ){ + jsonParseAddNode(pParse, JSON_OBJECT, 0, 0); + }else if( strncmp(zPath,"[0]",3)==0 ){ + jsonParseAddNode(pParse, JSON_ARRAY, 0, 0); + }else{ + return 0; + } + if( pParse->oom ) return 0; + return jsonLookupStep(pParse, pParse->nNode-1, zPath, pApnd, pzErr); +} + +/* +** Return the text of a syntax error message on a JSON path. Space is +** obtained from sqlite3_malloc(). +*/ +static char *jsonPathSyntaxError(const char *zErr){ + return sqlite3_mprintf("JSON path error near '%q'", zErr); +} + +/* +** Do a node lookup using zPath. Return a pointer to the node on success. +** Return NULL if not found or if there is an error. +** +** On an error, write an error message into pCtx and increment the +** pParse->nErr counter. +** +** If pApnd!=NULL then try to append missing nodes and set *pApnd = 1 if +** nodes are appended. +*/ +static JsonNode *jsonLookup( + JsonParse *pParse, /* The JSON to search */ + const char *zPath, /* The path to search */ + int *pApnd, /* Append nodes to complete path if not NULL */ + sqlite3_context *pCtx /* Report errors here, if not NULL */ +){ + const char *zErr = 0; + JsonNode *pNode = 0; + char *zMsg; + + if( zPath==0 ) return 0; + if( zPath[0]!='$' ){ + zErr = zPath; + goto lookup_err; + } + zPath++; + pNode = jsonLookupStep(pParse, 0, zPath, pApnd, &zErr); + if( zErr==0 ) return pNode; + +lookup_err: + pParse->nErr++; + assert( zErr!=0 && pCtx!=0 ); + zMsg = jsonPathSyntaxError(zErr); + if( zMsg ){ + sqlite3_result_error(pCtx, zMsg, -1); + sqlite3_free(zMsg); + }else{ + sqlite3_result_error_nomem(pCtx); + } + return 0; +} + + +/* +** Report the wrong number of arguments for json_insert(), json_replace() +** or json_set(). +*/ +static void jsonWrongNumArgs( + sqlite3_context *pCtx, + const char *zFuncName +){ + char *zMsg = sqlite3_mprintf("json_%s() needs an odd number of arguments", + zFuncName); + sqlite3_result_error(pCtx, zMsg, -1); + sqlite3_free(zMsg); +} + +/* +** Mark all NULL entries in the Object passed in as JNODE_REMOVE. +*/ +static void jsonRemoveAllNulls(JsonNode *pNode){ + int i, n; + assert( pNode->eType==JSON_OBJECT ); + n = pNode->n; + for(i=2; i<=n; i += jsonNodeSize(&pNode[i])+1){ + switch( pNode[i].eType ){ + case JSON_NULL: + pNode[i].jnFlags |= JNODE_REMOVE; + break; + case JSON_OBJECT: + jsonRemoveAllNulls(&pNode[i]); + break; + } + } +} + +/**************************************************************************** +** Utility routines for dealing with the binary BLOB representation of JSON +****************************************************************************/ + + +/* ** Expand pParse->aBlob so that it holds at least N bytes. ** ** Return the number of errors. @@ -2398,33 +2896,6 @@ json_parse_restart: } -/* Mark node i of pParse as being a child of iParent. Call recursively -** to fill in all the descendants of node i. -*/ -static void jsonParseFillInParentage(JsonParse *pParse, u32 i, u32 iParent){ - JsonNode *pNode = &pParse->aNode[i]; - u32 j; - pParse->aUp[i] = iParent; - switch( pNode->eType ){ - case JSON_ARRAY: { - for(j=1; j<=pNode->n; j += jsonNodeSize(pNode+j)){ - jsonParseFillInParentage(pParse, i+j, i); - } - break; - } - case JSON_OBJECT: { - for(j=1; j<=pNode->n; j += jsonNodeSize(pNode+j+1)+1){ - pParse->aUp[i+j] = i; - jsonParseFillInParentage(pParse, i+j+1, i); - } - break; - } - default: { - break; - } - } -} - /* ** Parse a complete JSON string. Return 0 on success or non-zero if there ** are any errors. If an error occurs, free all memory held by pParse, @@ -2469,473 +2940,6 @@ static int jsonParseB( return 0; } -/* -** Compute the parentage of all nodes in a completed parse. -*/ -static int jsonParseFindParents(JsonParse *pParse){ - u32 *aUp; - assert( pParse->aUp==0 ); - aUp = pParse->aUp = sqlite3_malloc64( sizeof(u32)*pParse->nNode ); - if( aUp==0 ){ - pParse->oom = 1; - return SQLITE_NOMEM; - } - jsonParseFillInParentage(pParse, 0, 0); - return SQLITE_OK; -} - -/* -** Magic number used for the JSON parse cache in sqlite3_get_auxdata() -*/ -#define JSON_CACHE_ID (-429938) /* First cache entry */ -#define JSON_CACHE_SZ 4 /* Max number of cache entries */ - -/* -** Obtain a complete parse of the JSON found in the pJson argument -** -** Use the sqlite3_get_auxdata() cache to find a preexisting parse -** if it is available. If the cache is not available or if it -** is no longer valid, parse the JSON again and return the new parse. -** Also register the new parse so that it will be available for -** future sqlite3_get_auxdata() calls. -** -** If an error occurs and pErrCtx!=0 then report the error on pErrCtx -** and return NULL. -** -** The returned pointer (if it is not NULL) is owned by the cache in -** most cases, not the caller. The caller does NOT need to invoke -** jsonParseFree(), in most cases. -** -** Except, if an error occurs and pErrCtx==0 then return the JsonParse -** object with JsonParse.nErr non-zero and the caller will own the JsonParse -** object. In that case, it will be the responsibility of the caller to -** invoke jsonParseFree(). To summarize: -** -** pErrCtx!=0 || p->nErr==0 ==> Return value p is owned by the -** cache. Call does not need to -** free it. -** -** pErrCtx==0 && p->nErr!=0 ==> Return value is owned by the caller -** and so the caller must free it. -*/ -static JsonParse *jsonParseCached( - sqlite3_context *pCtx, /* Context to use for cache search */ - sqlite3_value *pJson, /* Function param containing JSON text */ - sqlite3_context *pErrCtx, /* Write parse errors here if not NULL */ - int bUnedited /* No prior edits allowed */ -){ - char *zJson = (char*)sqlite3_value_text(pJson); - int nJson = sqlite3_value_bytes(pJson); - JsonParse *p; - JsonParse *pMatch = 0; - int iKey; - int iMinKey = 0; - u32 iMinHold = 0xffffffff; - u32 iMaxHold = 0; - int bJsonRCStr; - - if( zJson==0 ) return 0; - for(iKey=0; iKey<JSON_CACHE_SZ; iKey++){ - p = (JsonParse*)sqlite3_get_auxdata(pCtx, JSON_CACHE_ID+iKey); - if( p==0 ){ - iMinKey = iKey; - break; - } - if( pMatch==0 - && p->nJson==nJson - && (p->hasMod==0 || bUnedited==0) - && (p->zJson==zJson || memcmp(p->zJson,zJson,nJson)==0) - ){ - p->nErr = 0; - p->useMod = 0; - pMatch = p; - }else - if( pMatch==0 - && p->zAlt!=0 - && bUnedited==0 - && p->nAlt==nJson - && memcmp(p->zAlt, zJson, nJson)==0 - ){ - p->nErr = 0; - p->useMod = 1; - pMatch = p; - }else if( p->iHold<iMinHold ){ - iMinHold = p->iHold; - iMinKey = iKey; - } - if( p->iHold>iMaxHold ){ - iMaxHold = p->iHold; - } - } - if( pMatch ){ - /* The input JSON text was found in the cache. Use the preexisting - ** parse of this JSON */ - pMatch->nErr = 0; - pMatch->iHold = iMaxHold+1; - assert( pMatch->nJPRef>0 ); /* pMatch is owned by the cache */ - return pMatch; - } - - /* The input JSON was not found anywhere in the cache. We will need - ** to parse it ourselves and generate a new JsonParse object. - */ - 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)); - if( bJsonRCStr ){ - p->zJson = sqlite3RCStrRef(zJson); - p->bJsonIsRCStr = 1; - }else{ - p->zJson = (char*)&p[1]; - memcpy(p->zJson, zJson, nJson+1); - } - p->nJPRef = 1; - if( jsonParse(p, pErrCtx) ){ - if( pErrCtx==0 ){ - p->nErr = 1; - assert( p->nJPRef==1 ); /* Caller will own the new JsonParse object p */ - return p; - } - jsonParseFree(p); - return 0; - } - p->nJson = nJson; - p->iHold = iMaxHold+1; - /* Transfer ownership of the new JsonParse to the cache */ - sqlite3_set_auxdata(pCtx, JSON_CACHE_ID+iMinKey, p, - (void(*)(void*))jsonParseFree); - return (JsonParse*)sqlite3_get_auxdata(pCtx, JSON_CACHE_ID+iMinKey); -} - -/* -** Compare the OBJECT label at pNode against zKey,nKey. Return true on -** a match. -*/ -static int jsonLabelCompare(const JsonNode *pNode, const char *zKey, u32 nKey){ - assert( pNode->eU==1 ); - if( pNode->jnFlags & JNODE_RAW ){ - if( pNode->n!=nKey ) return 0; - return strncmp(pNode->u.zJContent, zKey, nKey)==0; - }else{ - if( pNode->n!=nKey+2 ) return 0; - return strncmp(pNode->u.zJContent+1, zKey, nKey)==0; - } -} -static int jsonSameLabel(const JsonNode *p1, const JsonNode *p2){ - if( p1->jnFlags & JNODE_RAW ){ - return jsonLabelCompare(p2, p1->u.zJContent, p1->n); - }else if( p2->jnFlags & JNODE_RAW ){ - return jsonLabelCompare(p1, p2->u.zJContent, p2->n); - }else{ - return p1->n==p2->n && strncmp(p1->u.zJContent,p2->u.zJContent,p1->n)==0; - } -} - -/* forward declaration */ -static JsonNode *jsonLookupAppend(JsonParse*,const char*,int*,const char**); - -/* -** Search along zPath to find the node specified. Return a pointer -** to that node, or NULL if zPath is malformed or if there is no such -** node. -** -** If pApnd!=0, then try to append new nodes to complete zPath if it is -** possible to do so and if no existing node corresponds to zPath. If -** new nodes are appended *pApnd is set to 1. -*/ -static JsonNode *jsonLookupStep( - JsonParse *pParse, /* The JSON to search */ - u32 iRoot, /* Begin the search at this node */ - const char *zPath, /* The path to search */ - int *pApnd, /* Append nodes to complete path if not NULL */ - const char **pzErr /* Make *pzErr point to any syntax error in zPath */ -){ - u32 i, j, nKey; - const char *zKey; - JsonNode *pRoot; - if( pParse->oom ) return 0; - pRoot = &pParse->aNode[iRoot]; - if( pRoot->jnFlags & (JNODE_REPLACE|JNODE_REMOVE) && pParse->useMod ){ - while( (pRoot->jnFlags & JNODE_REPLACE)!=0 ){ - u32 idx = (u32)(pRoot - pParse->aNode); - i = pParse->iSubst; - while( 1 /*exit-by-break*/ ){ - assert( i<pParse->nNode ); - assert( pParse->aNode[i].eType==JSON_SUBST ); - assert( pParse->aNode[i].eU==4 ); - assert( pParse->aNode[i].u.iPrev<i ); - if( pParse->aNode[i].n==idx ){ - pRoot = &pParse->aNode[i+1]; - iRoot = i+1; - break; - } - i = pParse->aNode[i].u.iPrev; - } - } - if( pRoot->jnFlags & JNODE_REMOVE ){ - return 0; - } - } - if( zPath[0]==0 ) return pRoot; - if( zPath[0]=='.' ){ - if( pRoot->eType!=JSON_OBJECT ) return 0; - zPath++; - if( zPath[0]=='"' ){ - zKey = zPath + 1; - for(i=1; zPath[i] && zPath[i]!='"'; i++){} - nKey = i-1; - if( zPath[i] ){ - i++; - }else{ - *pzErr = zPath; - return 0; - } - testcase( nKey==0 ); - }else{ - zKey = zPath; - for(i=0; zPath[i] && zPath[i]!='.' && zPath[i]!='['; i++){} - nKey = i; - if( nKey==0 ){ - *pzErr = zPath; - return 0; - } - } - j = 1; - for(;;){ - while( j<=pRoot->n ){ - if( jsonLabelCompare(pRoot+j, zKey, nKey) ){ - return jsonLookupStep(pParse, iRoot+j+1, &zPath[i], pApnd, pzErr); - } - j++; - j += jsonNodeSize(&pRoot[j]); - } - if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break; - if( pParse->useMod==0 ) break; - assert( pRoot->eU==2 ); - iRoot = pRoot->u.iAppend; - pRoot = &pParse->aNode[iRoot]; - j = 1; - } - if( pApnd ){ - u32 iStart, iLabel; - JsonNode *pNode; - assert( pParse->useMod ); - iStart = jsonParseAddNode(pParse, JSON_OBJECT, 2, 0); - iLabel = jsonParseAddNode(pParse, JSON_STRING, nKey, zKey); - zPath += i; - pNode = jsonLookupAppend(pParse, zPath, pApnd, pzErr); - if( pParse->oom ) return 0; - if( pNode ){ - pRoot = &pParse->aNode[iRoot]; - assert( pRoot->eU==0 ); - pRoot->u.iAppend = iStart; - pRoot->jnFlags |= JNODE_APPEND; - VVA( pRoot->eU = 2 ); - pParse->aNode[iLabel].jnFlags |= JNODE_RAW; - } - return pNode; - } - }else if( zPath[0]=='[' ){ - i = 0; - j = 1; - while( sqlite3Isdigit(zPath[j]) ){ - i = i*10 + zPath[j] - '0'; - j++; - } - if( j<2 || zPath[j]!=']' ){ - if( zPath[1]=='#' ){ - JsonNode *pBase = pRoot; - int iBase = iRoot; - if( pRoot->eType!=JSON_ARRAY ) return 0; - for(;;){ - while( j<=pBase->n ){ - if( (pBase[j].jnFlags & JNODE_REMOVE)==0 || pParse->useMod==0 ) i++; - j += jsonNodeSize(&pBase[j]); - } - if( (pBase->jnFlags & JNODE_APPEND)==0 ) break; - if( pParse->useMod==0 ) break; - assert( pBase->eU==2 ); - iBase = pBase->u.iAppend; - pBase = &pParse->aNode[iBase]; - j = 1; - } - j = 2; - if( zPath[2]=='-' && sqlite3Isdigit(zPath[3]) ){ - unsigned int x = 0; - j = 3; - do{ - x = x*10 + zPath[j] - '0'; - j++; - }while( sqlite3Isdigit(zPath[j]) ); - if( x>i ) return 0; - i -= x; - } - if( zPath[j]!=']' ){ - *pzErr = zPath; - return 0; - } - }else{ - *pzErr = zPath; - return 0; - } - } - if( pRoot->eType!=JSON_ARRAY ) return 0; - zPath += j + 1; - j = 1; - for(;;){ - while( j<=pRoot->n - && (i>0 || ((pRoot[j].jnFlags & JNODE_REMOVE)!=0 && pParse->useMod)) - ){ - if( (pRoot[j].jnFlags & JNODE_REMOVE)==0 || pParse->useMod==0 ) i--; - j += jsonNodeSize(&pRoot[j]); - } - if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break; - if( pParse->useMod==0 ) break; - assert( pRoot->eU==2 ); - iRoot = pRoot->u.iAppend; - pRoot = &pParse->aNode[iRoot]; - j = 1; - } - if( j<=pRoot->n ){ - return jsonLookupStep(pParse, iRoot+j, zPath, pApnd, pzErr); - } - if( i==0 && pApnd ){ - u32 iStart; - JsonNode *pNode; - assert( pParse->useMod ); - iStart = jsonParseAddNode(pParse, JSON_ARRAY, 1, 0); - pNode = jsonLookupAppend(pParse, zPath, pApnd, pzErr); - if( pParse->oom ) return 0; - if( pNode ){ - pRoot = &pParse->aNode[iRoot]; - assert( pRoot->eU==0 ); - pRoot->u.iAppend = iStart; - pRoot->jnFlags |= JNODE_APPEND; - VVA( pRoot->eU = 2 ); - } - return pNode; - } - }else{ - *pzErr = zPath; - } - return 0; -} - -/* -** Append content to pParse that will complete zPath. Return a pointer -** to the inserted node, or return NULL if the append fails. -*/ -static JsonNode *jsonLookupAppend( - JsonParse *pParse, /* Append content to the JSON parse */ - const char *zPath, /* Description of content to append */ - int *pApnd, /* Set this flag to 1 */ - const char **pzErr /* Make this point to any syntax error */ -){ - *pApnd = 1; - if( zPath[0]==0 ){ - jsonParseAddNode(pParse, JSON_NULL, 0, 0); - return pParse->oom ? 0 : &pParse->aNode[pParse->nNode-1]; - } - if( zPath[0]=='.' ){ - jsonParseAddNode(pParse, JSON_OBJECT, 0, 0); - }else if( strncmp(zPath,"[0]",3)==0 ){ - jsonParseAddNode(pParse, JSON_ARRAY, 0, 0); - }else{ - return 0; - } - if( pParse->oom ) return 0; - return jsonLookupStep(pParse, pParse->nNode-1, zPath, pApnd, pzErr); -} - -/* -** Return the text of a syntax error message on a JSON path. Space is -** obtained from sqlite3_malloc(). -*/ -static char *jsonPathSyntaxError(const char *zErr){ - return sqlite3_mprintf("JSON path error near '%q'", zErr); -} - -/* -** Do a node lookup using zPath. Return a pointer to the node on success. -** Return NULL if not found or if there is an error. -** -** On an error, write an error message into pCtx and increment the -** pParse->nErr counter. -** -** If pApnd!=NULL then try to append missing nodes and set *pApnd = 1 if -** nodes are appended. -*/ -static JsonNode *jsonLookup( - JsonParse *pParse, /* The JSON to search */ - const char *zPath, /* The path to search */ - int *pApnd, /* Append nodes to complete path if not NULL */ - sqlite3_context *pCtx /* Report errors here, if not NULL */ -){ - const char *zErr = 0; - JsonNode *pNode = 0; - char *zMsg; - - if( zPath==0 ) return 0; - if( zPath[0]!='$' ){ - zErr = zPath; - goto lookup_err; - } - zPath++; - pNode = jsonLookupStep(pParse, 0, zPath, pApnd, &zErr); - if( zErr==0 ) return pNode; - -lookup_err: - pParse->nErr++; - assert( zErr!=0 && pCtx!=0 ); - zMsg = jsonPathSyntaxError(zErr); - if( zMsg ){ - sqlite3_result_error(pCtx, zMsg, -1); - sqlite3_free(zMsg); - }else{ - sqlite3_result_error_nomem(pCtx); - } - return 0; -} - - -/* -** Report the wrong number of arguments for json_insert(), json_replace() -** or json_set(). -*/ -static void jsonWrongNumArgs( - sqlite3_context *pCtx, - const char *zFuncName -){ - char *zMsg = sqlite3_mprintf("json_%s() needs an odd number of arguments", - zFuncName); - sqlite3_result_error(pCtx, zMsg, -1); - sqlite3_free(zMsg); -} - -/* -** Mark all NULL entries in the Object passed in as JNODE_REMOVE. -*/ -static void jsonRemoveAllNulls(JsonNode *pNode){ - int i, n; - assert( pNode->eType==JSON_OBJECT ); - n = pNode->n; - for(i=2; i<=n; i += jsonNodeSize(&pNode[i])+1){ - switch( pNode[i].eType ){ - case JSON_NULL: - pNode[i].jnFlags |= JNODE_REMOVE; - break; - case JSON_OBJECT: - jsonRemoveAllNulls(&pNode[i]); - break; - } - } -} - - /**************************************************************************** ** SQL functions used for testing and debugging ****************************************************************************/ |