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-rw-r--r--src/backend/utils/adt/jsonpath.c1075
1 files changed, 1075 insertions, 0 deletions
diff --git a/src/backend/utils/adt/jsonpath.c b/src/backend/utils/adt/jsonpath.c
new file mode 100644
index 0000000..fa22546
--- /dev/null
+++ b/src/backend/utils/adt/jsonpath.c
@@ -0,0 +1,1075 @@
+/*-------------------------------------------------------------------------
+ *
+ * jsonpath.c
+ * Input/output and supporting routines for jsonpath
+ *
+ * jsonpath expression is a chain of path items. First path item is $, $var,
+ * literal or arithmetic expression. Subsequent path items are accessors
+ * (.key, .*, [subscripts], [*]), filters (? (predicate)) and methods (.type(),
+ * .size() etc).
+ *
+ * For instance, structure of path items for simple expression:
+ *
+ * $.a[*].type()
+ *
+ * is pretty evident:
+ *
+ * $ => .a => [*] => .type()
+ *
+ * Some path items such as arithmetic operations, predicates or array
+ * subscripts may comprise subtrees. For instance, more complex expression
+ *
+ * ($.a + $[1 to 5, 7] ? (@ > 3).double()).type()
+ *
+ * have following structure of path items:
+ *
+ * + => .type()
+ * ___/ \___
+ * / \
+ * $ => .a $ => [] => ? => .double()
+ * _||_ |
+ * / \ >
+ * to to / \
+ * / \ / @ 3
+ * 1 5 7
+ *
+ * Binary encoding of jsonpath constitutes a sequence of 4-bytes aligned
+ * variable-length path items connected by links. Every item has a header
+ * consisting of item type (enum JsonPathItemType) and offset of next item
+ * (zero means no next item). After the header, item may have payload
+ * depending on item type. For instance, payload of '.key' accessor item is
+ * length of key name and key name itself. Payload of '>' arithmetic operator
+ * item is offsets of right and left operands.
+ *
+ * So, binary representation of sample expression above is:
+ * (bottom arrows are next links, top lines are argument links)
+ *
+ * _____
+ * _____ ___/____ \ __
+ * _ /_ \ _____/__/____ \ \ __ _ /_ \
+ * / / \ \ / / / \ \ \ / \ / / \ \
+ * +(LR) $ .a $ [](* to *, * to *) 1 5 7 ?(A) >(LR) @ 3 .double() .type()
+ * | | ^ | ^| ^| ^ ^
+ * | |__| |__||________________________||___________________| |
+ * |_______________________________________________________________________|
+ *
+ * Copyright (c) 2019-2021, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/backend/utils/adt/jsonpath.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "funcapi.h"
+#include "lib/stringinfo.h"
+#include "libpq/pqformat.h"
+#include "miscadmin.h"
+#include "utils/builtins.h"
+#include "utils/json.h"
+#include "utils/jsonpath.h"
+
+
+static Datum jsonPathFromCstring(char *in, int len);
+static char *jsonPathToCstring(StringInfo out, JsonPath *in,
+ int estimated_len);
+static int flattenJsonPathParseItem(StringInfo buf, JsonPathParseItem *item,
+ int nestingLevel, bool insideArraySubscript);
+static void alignStringInfoInt(StringInfo buf);
+static int32 reserveSpaceForItemPointer(StringInfo buf);
+static void printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey,
+ bool printBracketes);
+static int operationPriority(JsonPathItemType op);
+
+
+/**************************** INPUT/OUTPUT ********************************/
+
+/*
+ * jsonpath type input function
+ */
+Datum
+jsonpath_in(PG_FUNCTION_ARGS)
+{
+ char *in = PG_GETARG_CSTRING(0);
+ int len = strlen(in);
+
+ return jsonPathFromCstring(in, len);
+}
+
+/*
+ * jsonpath type recv function
+ *
+ * The type is sent as text in binary mode, so this is almost the same
+ * as the input function, but it's prefixed with a version number so we
+ * can change the binary format sent in future if necessary. For now,
+ * only version 1 is supported.
+ */
+Datum
+jsonpath_recv(PG_FUNCTION_ARGS)
+{
+ StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
+ int version = pq_getmsgint(buf, 1);
+ char *str;
+ int nbytes;
+
+ if (version == JSONPATH_VERSION)
+ str = pq_getmsgtext(buf, buf->len - buf->cursor, &nbytes);
+ else
+ elog(ERROR, "unsupported jsonpath version number: %d", version);
+
+ return jsonPathFromCstring(str, nbytes);
+}
+
+/*
+ * jsonpath type output function
+ */
+Datum
+jsonpath_out(PG_FUNCTION_ARGS)
+{
+ JsonPath *in = PG_GETARG_JSONPATH_P(0);
+
+ PG_RETURN_CSTRING(jsonPathToCstring(NULL, in, VARSIZE(in)));
+}
+
+/*
+ * jsonpath type send function
+ *
+ * Just send jsonpath as a version number, then a string of text
+ */
+Datum
+jsonpath_send(PG_FUNCTION_ARGS)
+{
+ JsonPath *in = PG_GETARG_JSONPATH_P(0);
+ StringInfoData buf;
+ StringInfoData jtext;
+ int version = JSONPATH_VERSION;
+
+ initStringInfo(&jtext);
+ (void) jsonPathToCstring(&jtext, in, VARSIZE(in));
+
+ pq_begintypsend(&buf);
+ pq_sendint8(&buf, version);
+ pq_sendtext(&buf, jtext.data, jtext.len);
+ pfree(jtext.data);
+
+ PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
+
+/*
+ * Converts C-string to a jsonpath value.
+ *
+ * Uses jsonpath parser to turn string into an AST, then
+ * flattenJsonPathParseItem() does second pass turning AST into binary
+ * representation of jsonpath.
+ */
+static Datum
+jsonPathFromCstring(char *in, int len)
+{
+ JsonPathParseResult *jsonpath = parsejsonpath(in, len);
+ JsonPath *res;
+ StringInfoData buf;
+
+ initStringInfo(&buf);
+ enlargeStringInfo(&buf, 4 * len /* estimation */ );
+
+ appendStringInfoSpaces(&buf, JSONPATH_HDRSZ);
+
+ if (!jsonpath)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+ errmsg("invalid input syntax for type %s: \"%s\"", "jsonpath",
+ in)));
+
+ flattenJsonPathParseItem(&buf, jsonpath->expr, 0, false);
+
+ res = (JsonPath *) buf.data;
+ SET_VARSIZE(res, buf.len);
+ res->header = JSONPATH_VERSION;
+ if (jsonpath->lax)
+ res->header |= JSONPATH_LAX;
+
+ PG_RETURN_JSONPATH_P(res);
+}
+
+/*
+ * Converts jsonpath value to a C-string.
+ *
+ * If 'out' argument is non-null, the resulting C-string is stored inside the
+ * StringBuffer. The resulting string is always returned.
+ */
+static char *
+jsonPathToCstring(StringInfo out, JsonPath *in, int estimated_len)
+{
+ StringInfoData buf;
+ JsonPathItem v;
+
+ if (!out)
+ {
+ out = &buf;
+ initStringInfo(out);
+ }
+ enlargeStringInfo(out, estimated_len);
+
+ if (!(in->header & JSONPATH_LAX))
+ appendBinaryStringInfo(out, "strict ", 7);
+
+ jspInit(&v, in);
+ printJsonPathItem(out, &v, false, true);
+
+ return out->data;
+}
+
+/*
+ * Recursive function converting given jsonpath parse item and all its
+ * children into a binary representation.
+ */
+static int
+flattenJsonPathParseItem(StringInfo buf, JsonPathParseItem *item,
+ int nestingLevel, bool insideArraySubscript)
+{
+ /* position from beginning of jsonpath data */
+ int32 pos = buf->len - JSONPATH_HDRSZ;
+ int32 chld;
+ int32 next;
+ int argNestingLevel = 0;
+
+ check_stack_depth();
+ CHECK_FOR_INTERRUPTS();
+
+ appendStringInfoChar(buf, (char) (item->type));
+
+ /*
+ * We align buffer to int32 because a series of int32 values often goes
+ * after the header, and we want to read them directly by dereferencing
+ * int32 pointer (see jspInitByBuffer()).
+ */
+ alignStringInfoInt(buf);
+
+ /*
+ * Reserve space for next item pointer. Actual value will be recorded
+ * later, after next and children items processing.
+ */
+ next = reserveSpaceForItemPointer(buf);
+
+ switch (item->type)
+ {
+ case jpiString:
+ case jpiVariable:
+ case jpiKey:
+ appendBinaryStringInfo(buf, (char *) &item->value.string.len,
+ sizeof(item->value.string.len));
+ appendBinaryStringInfo(buf, item->value.string.val,
+ item->value.string.len);
+ appendStringInfoChar(buf, '\0');
+ break;
+ case jpiNumeric:
+ appendBinaryStringInfo(buf, (char *) item->value.numeric,
+ VARSIZE(item->value.numeric));
+ break;
+ case jpiBool:
+ appendBinaryStringInfo(buf, (char *) &item->value.boolean,
+ sizeof(item->value.boolean));
+ break;
+ case jpiAnd:
+ case jpiOr:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiAdd:
+ case jpiSub:
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ case jpiStartsWith:
+ {
+ /*
+ * First, reserve place for left/right arg's positions, then
+ * record both args and sets actual position in reserved
+ * places.
+ */
+ int32 left = reserveSpaceForItemPointer(buf);
+ int32 right = reserveSpaceForItemPointer(buf);
+
+ chld = !item->value.args.left ? pos :
+ flattenJsonPathParseItem(buf, item->value.args.left,
+ nestingLevel + argNestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + left) = chld - pos;
+
+ chld = !item->value.args.right ? pos :
+ flattenJsonPathParseItem(buf, item->value.args.right,
+ nestingLevel + argNestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + right) = chld - pos;
+ }
+ break;
+ case jpiLikeRegex:
+ {
+ int32 offs;
+
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.like_regex.flags,
+ sizeof(item->value.like_regex.flags));
+ offs = reserveSpaceForItemPointer(buf);
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.like_regex.patternlen,
+ sizeof(item->value.like_regex.patternlen));
+ appendBinaryStringInfo(buf, item->value.like_regex.pattern,
+ item->value.like_regex.patternlen);
+ appendStringInfoChar(buf, '\0');
+
+ chld = flattenJsonPathParseItem(buf, item->value.like_regex.expr,
+ nestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + offs) = chld - pos;
+ }
+ break;
+ case jpiFilter:
+ argNestingLevel++;
+ /* FALLTHROUGH */
+ case jpiIsUnknown:
+ case jpiNot:
+ case jpiPlus:
+ case jpiMinus:
+ case jpiExists:
+ case jpiDatetime:
+ {
+ int32 arg = reserveSpaceForItemPointer(buf);
+
+ chld = !item->value.arg ? pos :
+ flattenJsonPathParseItem(buf, item->value.arg,
+ nestingLevel + argNestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + arg) = chld - pos;
+ }
+ break;
+ case jpiNull:
+ break;
+ case jpiRoot:
+ break;
+ case jpiAnyArray:
+ case jpiAnyKey:
+ break;
+ case jpiCurrent:
+ if (nestingLevel <= 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("@ is not allowed in root expressions")));
+ break;
+ case jpiLast:
+ if (!insideArraySubscript)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("LAST is allowed only in array subscripts")));
+ break;
+ case jpiIndexArray:
+ {
+ int32 nelems = item->value.array.nelems;
+ int offset;
+ int i;
+
+ appendBinaryStringInfo(buf, (char *) &nelems, sizeof(nelems));
+
+ offset = buf->len;
+
+ appendStringInfoSpaces(buf, sizeof(int32) * 2 * nelems);
+
+ for (i = 0; i < nelems; i++)
+ {
+ int32 *ppos;
+ int32 topos;
+ int32 frompos =
+ flattenJsonPathParseItem(buf,
+ item->value.array.elems[i].from,
+ nestingLevel, true) - pos;
+
+ if (item->value.array.elems[i].to)
+ topos = flattenJsonPathParseItem(buf,
+ item->value.array.elems[i].to,
+ nestingLevel, true) - pos;
+ else
+ topos = 0;
+
+ ppos = (int32 *) &buf->data[offset + i * 2 * sizeof(int32)];
+
+ ppos[0] = frompos;
+ ppos[1] = topos;
+ }
+ }
+ break;
+ case jpiAny:
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.anybounds.first,
+ sizeof(item->value.anybounds.first));
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.anybounds.last,
+ sizeof(item->value.anybounds.last));
+ break;
+ case jpiType:
+ case jpiSize:
+ case jpiAbs:
+ case jpiFloor:
+ case jpiCeiling:
+ case jpiDouble:
+ case jpiKeyValue:
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", item->type);
+ }
+
+ if (item->next)
+ {
+ chld = flattenJsonPathParseItem(buf, item->next, nestingLevel,
+ insideArraySubscript) - pos;
+ *(int32 *) (buf->data + next) = chld;
+ }
+
+ return pos;
+}
+
+/*
+ * Align StringInfo to int by adding zero padding bytes
+ */
+static void
+alignStringInfoInt(StringInfo buf)
+{
+ switch (INTALIGN(buf->len) - buf->len)
+ {
+ case 3:
+ appendStringInfoCharMacro(buf, 0);
+ /* FALLTHROUGH */
+ case 2:
+ appendStringInfoCharMacro(buf, 0);
+ /* FALLTHROUGH */
+ case 1:
+ appendStringInfoCharMacro(buf, 0);
+ /* FALLTHROUGH */
+ default:
+ break;
+ }
+}
+
+/*
+ * Reserve space for int32 JsonPathItem pointer. Now zero pointer is written,
+ * actual value will be recorded at '(int32 *) &buf->data[pos]' later.
+ */
+static int32
+reserveSpaceForItemPointer(StringInfo buf)
+{
+ int32 pos = buf->len;
+ int32 ptr = 0;
+
+ appendBinaryStringInfo(buf, (char *) &ptr, sizeof(ptr));
+
+ return pos;
+}
+
+/*
+ * Prints text representation of given jsonpath item and all its children.
+ */
+static void
+printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey,
+ bool printBracketes)
+{
+ JsonPathItem elem;
+ int i;
+
+ check_stack_depth();
+ CHECK_FOR_INTERRUPTS();
+
+ switch (v->type)
+ {
+ case jpiNull:
+ appendStringInfoString(buf, "null");
+ break;
+ case jpiKey:
+ if (inKey)
+ appendStringInfoChar(buf, '.');
+ escape_json(buf, jspGetString(v, NULL));
+ break;
+ case jpiString:
+ escape_json(buf, jspGetString(v, NULL));
+ break;
+ case jpiVariable:
+ appendStringInfoChar(buf, '$');
+ escape_json(buf, jspGetString(v, NULL));
+ break;
+ case jpiNumeric:
+ appendStringInfoString(buf,
+ DatumGetCString(DirectFunctionCall1(numeric_out,
+ NumericGetDatum(jspGetNumeric(v)))));
+ break;
+ case jpiBool:
+ if (jspGetBool(v))
+ appendBinaryStringInfo(buf, "true", 4);
+ else
+ appendBinaryStringInfo(buf, "false", 5);
+ break;
+ case jpiAnd:
+ case jpiOr:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiAdd:
+ case jpiSub:
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ case jpiStartsWith:
+ if (printBracketes)
+ appendStringInfoChar(buf, '(');
+ jspGetLeftArg(v, &elem);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+ appendStringInfoChar(buf, ' ');
+ appendStringInfoString(buf, jspOperationName(v->type));
+ appendStringInfoChar(buf, ' ');
+ jspGetRightArg(v, &elem);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+ if (printBracketes)
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiLikeRegex:
+ if (printBracketes)
+ appendStringInfoChar(buf, '(');
+
+ jspInitByBuffer(&elem, v->base, v->content.like_regex.expr);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+
+ appendBinaryStringInfo(buf, " like_regex ", 12);
+
+ escape_json(buf, v->content.like_regex.pattern);
+
+ if (v->content.like_regex.flags)
+ {
+ appendBinaryStringInfo(buf, " flag \"", 7);
+
+ if (v->content.like_regex.flags & JSP_REGEX_ICASE)
+ appendStringInfoChar(buf, 'i');
+ if (v->content.like_regex.flags & JSP_REGEX_DOTALL)
+ appendStringInfoChar(buf, 's');
+ if (v->content.like_regex.flags & JSP_REGEX_MLINE)
+ appendStringInfoChar(buf, 'm');
+ if (v->content.like_regex.flags & JSP_REGEX_WSPACE)
+ appendStringInfoChar(buf, 'x');
+ if (v->content.like_regex.flags & JSP_REGEX_QUOTE)
+ appendStringInfoChar(buf, 'q');
+
+ appendStringInfoChar(buf, '"');
+ }
+
+ if (printBracketes)
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiPlus:
+ case jpiMinus:
+ if (printBracketes)
+ appendStringInfoChar(buf, '(');
+ appendStringInfoChar(buf, v->type == jpiPlus ? '+' : '-');
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+ if (printBracketes)
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiFilter:
+ appendBinaryStringInfo(buf, "?(", 2);
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiNot:
+ appendBinaryStringInfo(buf, "!(", 2);
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiIsUnknown:
+ appendStringInfoChar(buf, '(');
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendBinaryStringInfo(buf, ") is unknown", 12);
+ break;
+ case jpiExists:
+ appendBinaryStringInfo(buf, "exists (", 8);
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiCurrent:
+ Assert(!inKey);
+ appendStringInfoChar(buf, '@');
+ break;
+ case jpiRoot:
+ Assert(!inKey);
+ appendStringInfoChar(buf, '$');
+ break;
+ case jpiLast:
+ appendBinaryStringInfo(buf, "last", 4);
+ break;
+ case jpiAnyArray:
+ appendBinaryStringInfo(buf, "[*]", 3);
+ break;
+ case jpiAnyKey:
+ if (inKey)
+ appendStringInfoChar(buf, '.');
+ appendStringInfoChar(buf, '*');
+ break;
+ case jpiIndexArray:
+ appendStringInfoChar(buf, '[');
+ for (i = 0; i < v->content.array.nelems; i++)
+ {
+ JsonPathItem from;
+ JsonPathItem to;
+ bool range = jspGetArraySubscript(v, &from, &to, i);
+
+ if (i)
+ appendStringInfoChar(buf, ',');
+
+ printJsonPathItem(buf, &from, false, false);
+
+ if (range)
+ {
+ appendBinaryStringInfo(buf, " to ", 4);
+ printJsonPathItem(buf, &to, false, false);
+ }
+ }
+ appendStringInfoChar(buf, ']');
+ break;
+ case jpiAny:
+ if (inKey)
+ appendStringInfoChar(buf, '.');
+
+ if (v->content.anybounds.first == 0 &&
+ v->content.anybounds.last == PG_UINT32_MAX)
+ appendBinaryStringInfo(buf, "**", 2);
+ else if (v->content.anybounds.first == v->content.anybounds.last)
+ {
+ if (v->content.anybounds.first == PG_UINT32_MAX)
+ appendStringInfoString(buf, "**{last}");
+ else
+ appendStringInfo(buf, "**{%u}",
+ v->content.anybounds.first);
+ }
+ else if (v->content.anybounds.first == PG_UINT32_MAX)
+ appendStringInfo(buf, "**{last to %u}",
+ v->content.anybounds.last);
+ else if (v->content.anybounds.last == PG_UINT32_MAX)
+ appendStringInfo(buf, "**{%u to last}",
+ v->content.anybounds.first);
+ else
+ appendStringInfo(buf, "**{%u to %u}",
+ v->content.anybounds.first,
+ v->content.anybounds.last);
+ break;
+ case jpiType:
+ appendBinaryStringInfo(buf, ".type()", 7);
+ break;
+ case jpiSize:
+ appendBinaryStringInfo(buf, ".size()", 7);
+ break;
+ case jpiAbs:
+ appendBinaryStringInfo(buf, ".abs()", 6);
+ break;
+ case jpiFloor:
+ appendBinaryStringInfo(buf, ".floor()", 8);
+ break;
+ case jpiCeiling:
+ appendBinaryStringInfo(buf, ".ceiling()", 10);
+ break;
+ case jpiDouble:
+ appendBinaryStringInfo(buf, ".double()", 9);
+ break;
+ case jpiDatetime:
+ appendBinaryStringInfo(buf, ".datetime(", 10);
+ if (v->content.arg)
+ {
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ }
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiKeyValue:
+ appendBinaryStringInfo(buf, ".keyvalue()", 11);
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", v->type);
+ }
+
+ if (jspGetNext(v, &elem))
+ printJsonPathItem(buf, &elem, true, true);
+}
+
+const char *
+jspOperationName(JsonPathItemType type)
+{
+ switch (type)
+ {
+ case jpiAnd:
+ return "&&";
+ case jpiOr:
+ return "||";
+ case jpiEqual:
+ return "==";
+ case jpiNotEqual:
+ return "!=";
+ case jpiLess:
+ return "<";
+ case jpiGreater:
+ return ">";
+ case jpiLessOrEqual:
+ return "<=";
+ case jpiGreaterOrEqual:
+ return ">=";
+ case jpiPlus:
+ case jpiAdd:
+ return "+";
+ case jpiMinus:
+ case jpiSub:
+ return "-";
+ case jpiMul:
+ return "*";
+ case jpiDiv:
+ return "/";
+ case jpiMod:
+ return "%";
+ case jpiStartsWith:
+ return "starts with";
+ case jpiLikeRegex:
+ return "like_regex";
+ case jpiType:
+ return "type";
+ case jpiSize:
+ return "size";
+ case jpiKeyValue:
+ return "keyvalue";
+ case jpiDouble:
+ return "double";
+ case jpiAbs:
+ return "abs";
+ case jpiFloor:
+ return "floor";
+ case jpiCeiling:
+ return "ceiling";
+ case jpiDatetime:
+ return "datetime";
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", type);
+ return NULL;
+ }
+}
+
+static int
+operationPriority(JsonPathItemType op)
+{
+ switch (op)
+ {
+ case jpiOr:
+ return 0;
+ case jpiAnd:
+ return 1;
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiStartsWith:
+ return 2;
+ case jpiAdd:
+ case jpiSub:
+ return 3;
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ return 4;
+ case jpiPlus:
+ case jpiMinus:
+ return 5;
+ default:
+ return 6;
+ }
+}
+
+/******************* Support functions for JsonPath *************************/
+
+/*
+ * Support macros to read stored values
+ */
+
+#define read_byte(v, b, p) do { \
+ (v) = *(uint8*)((b) + (p)); \
+ (p) += 1; \
+} while(0) \
+
+#define read_int32(v, b, p) do { \
+ (v) = *(uint32*)((b) + (p)); \
+ (p) += sizeof(int32); \
+} while(0) \
+
+#define read_int32_n(v, b, p, n) do { \
+ (v) = (void *)((b) + (p)); \
+ (p) += sizeof(int32) * (n); \
+} while(0) \
+
+/*
+ * Read root node and fill root node representation
+ */
+void
+jspInit(JsonPathItem *v, JsonPath *js)
+{
+ Assert((js->header & ~JSONPATH_LAX) == JSONPATH_VERSION);
+ jspInitByBuffer(v, js->data, 0);
+}
+
+/*
+ * Read node from buffer and fill its representation
+ */
+void
+jspInitByBuffer(JsonPathItem *v, char *base, int32 pos)
+{
+ v->base = base + pos;
+
+ read_byte(v->type, base, pos);
+ pos = INTALIGN((uintptr_t) (base + pos)) - (uintptr_t) base;
+ read_int32(v->nextPos, base, pos);
+
+ switch (v->type)
+ {
+ case jpiNull:
+ case jpiRoot:
+ case jpiCurrent:
+ case jpiAnyArray:
+ case jpiAnyKey:
+ case jpiType:
+ case jpiSize:
+ case jpiAbs:
+ case jpiFloor:
+ case jpiCeiling:
+ case jpiDouble:
+ case jpiKeyValue:
+ case jpiLast:
+ break;
+ case jpiKey:
+ case jpiString:
+ case jpiVariable:
+ read_int32(v->content.value.datalen, base, pos);
+ /* FALLTHROUGH */
+ case jpiNumeric:
+ case jpiBool:
+ v->content.value.data = base + pos;
+ break;
+ case jpiAnd:
+ case jpiOr:
+ case jpiAdd:
+ case jpiSub:
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiStartsWith:
+ read_int32(v->content.args.left, base, pos);
+ read_int32(v->content.args.right, base, pos);
+ break;
+ case jpiLikeRegex:
+ read_int32(v->content.like_regex.flags, base, pos);
+ read_int32(v->content.like_regex.expr, base, pos);
+ read_int32(v->content.like_regex.patternlen, base, pos);
+ v->content.like_regex.pattern = base + pos;
+ break;
+ case jpiNot:
+ case jpiExists:
+ case jpiIsUnknown:
+ case jpiPlus:
+ case jpiMinus:
+ case jpiFilter:
+ case jpiDatetime:
+ read_int32(v->content.arg, base, pos);
+ break;
+ case jpiIndexArray:
+ read_int32(v->content.array.nelems, base, pos);
+ read_int32_n(v->content.array.elems, base, pos,
+ v->content.array.nelems * 2);
+ break;
+ case jpiAny:
+ read_int32(v->content.anybounds.first, base, pos);
+ read_int32(v->content.anybounds.last, base, pos);
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", v->type);
+ }
+}
+
+void
+jspGetArg(JsonPathItem *v, JsonPathItem *a)
+{
+ Assert(v->type == jpiFilter ||
+ v->type == jpiNot ||
+ v->type == jpiIsUnknown ||
+ v->type == jpiExists ||
+ v->type == jpiPlus ||
+ v->type == jpiMinus ||
+ v->type == jpiDatetime);
+
+ jspInitByBuffer(a, v->base, v->content.arg);
+}
+
+bool
+jspGetNext(JsonPathItem *v, JsonPathItem *a)
+{
+ if (jspHasNext(v))
+ {
+ Assert(v->type == jpiString ||
+ v->type == jpiNumeric ||
+ v->type == jpiBool ||
+ v->type == jpiNull ||
+ v->type == jpiKey ||
+ v->type == jpiAny ||
+ v->type == jpiAnyArray ||
+ v->type == jpiAnyKey ||
+ v->type == jpiIndexArray ||
+ v->type == jpiFilter ||
+ v->type == jpiCurrent ||
+ v->type == jpiExists ||
+ v->type == jpiRoot ||
+ v->type == jpiVariable ||
+ v->type == jpiLast ||
+ v->type == jpiAdd ||
+ v->type == jpiSub ||
+ v->type == jpiMul ||
+ v->type == jpiDiv ||
+ v->type == jpiMod ||
+ v->type == jpiPlus ||
+ v->type == jpiMinus ||
+ v->type == jpiEqual ||
+ v->type == jpiNotEqual ||
+ v->type == jpiGreater ||
+ v->type == jpiGreaterOrEqual ||
+ v->type == jpiLess ||
+ v->type == jpiLessOrEqual ||
+ v->type == jpiAnd ||
+ v->type == jpiOr ||
+ v->type == jpiNot ||
+ v->type == jpiIsUnknown ||
+ v->type == jpiType ||
+ v->type == jpiSize ||
+ v->type == jpiAbs ||
+ v->type == jpiFloor ||
+ v->type == jpiCeiling ||
+ v->type == jpiDouble ||
+ v->type == jpiDatetime ||
+ v->type == jpiKeyValue ||
+ v->type == jpiStartsWith);
+
+ if (a)
+ jspInitByBuffer(a, v->base, v->nextPos);
+ return true;
+ }
+
+ return false;
+}
+
+void
+jspGetLeftArg(JsonPathItem *v, JsonPathItem *a)
+{
+ Assert(v->type == jpiAnd ||
+ v->type == jpiOr ||
+ v->type == jpiEqual ||
+ v->type == jpiNotEqual ||
+ v->type == jpiLess ||
+ v->type == jpiGreater ||
+ v->type == jpiLessOrEqual ||
+ v->type == jpiGreaterOrEqual ||
+ v->type == jpiAdd ||
+ v->type == jpiSub ||
+ v->type == jpiMul ||
+ v->type == jpiDiv ||
+ v->type == jpiMod ||
+ v->type == jpiStartsWith);
+
+ jspInitByBuffer(a, v->base, v->content.args.left);
+}
+
+void
+jspGetRightArg(JsonPathItem *v, JsonPathItem *a)
+{
+ Assert(v->type == jpiAnd ||
+ v->type == jpiOr ||
+ v->type == jpiEqual ||
+ v->type == jpiNotEqual ||
+ v->type == jpiLess ||
+ v->type == jpiGreater ||
+ v->type == jpiLessOrEqual ||
+ v->type == jpiGreaterOrEqual ||
+ v->type == jpiAdd ||
+ v->type == jpiSub ||
+ v->type == jpiMul ||
+ v->type == jpiDiv ||
+ v->type == jpiMod ||
+ v->type == jpiStartsWith);
+
+ jspInitByBuffer(a, v->base, v->content.args.right);
+}
+
+bool
+jspGetBool(JsonPathItem *v)
+{
+ Assert(v->type == jpiBool);
+
+ return (bool) *v->content.value.data;
+}
+
+Numeric
+jspGetNumeric(JsonPathItem *v)
+{
+ Assert(v->type == jpiNumeric);
+
+ return (Numeric) v->content.value.data;
+}
+
+char *
+jspGetString(JsonPathItem *v, int32 *len)
+{
+ Assert(v->type == jpiKey ||
+ v->type == jpiString ||
+ v->type == jpiVariable);
+
+ if (len)
+ *len = v->content.value.datalen;
+ return v->content.value.data;
+}
+
+bool
+jspGetArraySubscript(JsonPathItem *v, JsonPathItem *from, JsonPathItem *to,
+ int i)
+{
+ Assert(v->type == jpiIndexArray);
+
+ jspInitByBuffer(from, v->base, v->content.array.elems[i].from);
+
+ if (!v->content.array.elems[i].to)
+ return false;
+
+ jspInitByBuffer(to, v->base, v->content.array.elems[i].to);
+
+ return true;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 11:20:14 +0000