libidav/davqlparser.c@b9c6e0be5774
libidav/davqlparser.c
Tue, 12 Dec 2017 23:58:54 +0100
- author
- Mike Becker <universe@uap-core.de>
- date
- Tue, 12 Dec 2017 23:58:54 +0100
- branch
- v1.1
- changeset 343
- b9c6e0be5774
- parent 291
- 8828260d2fd8
- child 356
- 699781a1d6fd
- permissions
- -rw-r--r--
fixes infinite loop when trying to overwrite a collection with a regular file
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright 2016 Olaf Wintermann. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include "davqlparser.h" #include <ucx/utils.h> #include <string.h> #include <stdio.h> #include <ctype.h> #define sfmtarg(s) ((int)(s).length), (s).ptr // ------------------------------------------------------------------------ // D E B U G E R // ------------------------------------------------------------------------ static const char* _map_querytype(davqltype_t type) { switch(type) { case DAVQL_ERROR: return "ERROR"; case DAVQL_SELECT: return "SELECT"; case DAVQL_SET: return "SET"; default: return "unknown"; } } static const char* _map_exprtype(davqlexprtype_t type) { switch(type) { case DAVQL_UNDEFINED_TYPE: return "undefined"; case DAVQL_NUMBER: return "NUMBER"; case DAVQL_STRING: return "STRING"; case DAVQL_TIMESTAMP: return "TIMESTAMP"; case DAVQL_IDENTIFIER: return "IDENTIFIER"; case DAVQL_UNARY: return "UNARY"; case DAVQL_BINARY: return "BINARY"; case DAVQL_LOGICAL: return "LOGICAL"; case DAVQL_FUNCCALL: return "FUNCCALL"; default: return "unknown"; } } static const char* _map_specialfield(int info) { switch(info) { case 0: return ""; case 1: return "with wildcard"; case 2: return "(resource data only)"; default: return "with mysterious identifier"; } } static const char* _map_operator(davqloperator_t op) { // don't use string array, because enum values may change switch(op) { case DAVQL_NOOP: return "no operator"; case DAVQL_CALL: return "function call"; case DAVQL_ARGLIST: return ","; case DAVQL_ADD: return "+"; case DAVQL_SUB: return "-"; case DAVQL_MUL: return "*"; case DAVQL_DIV: return "/"; case DAVQL_AND: return "&"; case DAVQL_OR: return "|"; case DAVQL_XOR: return "^"; case DAVQL_NEG: return "~"; case DAVQL_NOT: return "NOT"; case DAVQL_LAND: return "AND"; case DAVQL_LOR: return "OR"; case DAVQL_LXOR: return "XOR"; case DAVQL_EQ: return "="; case DAVQL_NEQ: return "!="; case DAVQL_LT: return "<"; case DAVQL_GT: return ">"; case DAVQL_LE: return "<="; case DAVQL_GE: return ">="; case DAVQL_LIKE: return "LIKE"; case DAVQL_UNLIKE: return "UNLIKE"; default: return "unknown"; } } static void dav_debug_ql_fnames_print(DavQLStatement *stmt) { if (stmt->fields) { printf("Field names: "); UCX_FOREACH(field, stmt->fields) { DavQLField *f = field->data; printf("%.*s, ", sfmtarg(f->name)); } printf("\b\b \b\b\n"); } } static void dav_debug_ql_stmt_print(DavQLStatement *stmt) { // Basic information size_t fieldcount = ucx_list_size(stmt->fields); int specialfield = 0; if (stmt->fields) { DavQLField* firstfield = (DavQLField*)stmt->fields->data; if (firstfield->expr->type == DAVQL_IDENTIFIER) { switch (firstfield->expr->srctext.ptr[0]) { case '*': specialfield = 1; break; case '-': specialfield = 2; break; } } } if (specialfield) { fieldcount--; } printf("Statement: %.*s\nType: %s\nField count: %zu %s\n", sfmtarg(stmt->srctext), _map_querytype(stmt->type), fieldcount, _map_specialfield(specialfield)); dav_debug_ql_fnames_print(stmt); printf("Path: %.*s\nHas where clause: %s\n", sfmtarg(stmt->path), stmt->where ? "yes" : "no"); // WITH attributes if (stmt->depth == DAV_DEPTH_INFINITY) { printf("Depth: infinity\n"); } else if (stmt->depth == DAV_DEPTH_PLACEHOLDER) { printf("Depth: placeholder\n"); } else { printf("Depth: %d\n", stmt->depth); } // order by clause printf("Order by: "); if (stmt->orderby) { UCX_FOREACH(crit, stmt->orderby) { DavQLOrderCriterion *critdata = crit->data; printf("%.*s %s%s", sfmtarg(critdata->column->srctext), critdata->descending ? "desc" : "asc", crit->next ? ", " : "\n"); } } else { printf("nothing\n"); } // error messages if (stmt->errorcode) { printf("\nError code: %d\nError: %s\n", stmt->errorcode, stmt->errormessage); } } static int dav_debug_ql_expr_selected(DavQLExpression *expr) { if (!expr) { printf("Currently no expression selected.\n"); return 0; } else { return 1; } } static void dav_debug_ql_expr_print(DavQLExpression *expr) { if (dav_debug_ql_expr_selected(expr)) { sstr_t empty = ST("(empty)"); printf( "Text: %.*s\nType: %s\nOperator: %s\n", sfmtarg(expr->srctext), _map_exprtype(expr->type), _map_operator(expr->op)); if (expr->left || expr->right) { printf("Left hand: %.*s\nRight hand: %.*s\n", sfmtarg(expr->left?expr->left->srctext:empty), sfmtarg(expr->right?expr->right->srctext:empty)); } } } static void dav_debug_ql_tree_print(DavQLExpression *expr, int depth) { if (expr) { if (expr->left) { printf("%*c%s\n", depth, ' ', _map_operator(expr->op)); dav_debug_ql_tree_print(expr->left, depth+1); dav_debug_ql_tree_print(expr->right, depth+1); } else if (expr->type == DAVQL_UNARY) { printf("%*c%s %.*s\n", depth, ' ', _map_operator(expr->op), sfmtarg(expr->srctext)); } else { printf("%*c%.*s\n", depth, ' ', sfmtarg(expr->srctext)); } } } #define DQLD_CMD_Q 0 #define DQLD_CMD_PS 1 #define DQLD_CMD_PE 2 #define DQLD_CMD_PF 3 #define DQLD_CMD_PT 4 #define DQLD_CMD_F 10 #define DQLD_CMD_W 11 #define DQLD_CMD_O 12 #define DQLD_CMD_L 21 #define DQLD_CMD_R 22 #define DQLD_CMD_N 23 #define DQLD_CMD_P 24 #define DQLD_CMD_H 100 static int dav_debug_ql_command() { printf("> "); char buffer[8]; fgets(buffer, 8, stdin); // discard remaining chars if (!strchr(buffer, '\n')) { int chr; while ((chr = fgetc(stdin) != '\n') && chr != EOF); } if (!strcmp(buffer, "q\n")) { return DQLD_CMD_Q; } else if (!strcmp(buffer, "ps\n")) { return DQLD_CMD_PS; } else if (!strcmp(buffer, "pe\n")) { return DQLD_CMD_PE; } else if (!strcmp(buffer, "pf\n")) { return DQLD_CMD_PF; } else if (!strcmp(buffer, "pt\n")) { return DQLD_CMD_PT; } else if (!strcmp(buffer, "l\n")) { return DQLD_CMD_L; } else if (!strcmp(buffer, "r\n")) { return DQLD_CMD_R; } else if (!strcmp(buffer, "h\n")) { return DQLD_CMD_H; } else if (!strcmp(buffer, "f\n")) { return DQLD_CMD_F; } else if (!strcmp(buffer, "w\n")) { return DQLD_CMD_W; } else if (!strcmp(buffer, "o\n")) { return DQLD_CMD_O; } else if (!strcmp(buffer, "n\n")) { return DQLD_CMD_N; } else if (!strcmp(buffer, "p\n")) { return DQLD_CMD_P; } else { return -1; } } void dav_debug_statement(DavQLStatement *stmt) { if (!stmt) { fprintf(stderr, "Debug DavQLStatement failed: null pointer"); return; } printf("Starting DavQL debugger (type 'h' for help)...\n\n"); dav_debug_ql_stmt_print(stmt); if (stmt->errorcode) { return; } DavQLExpression *examineexpr = NULL; UcxList *examineelem = NULL; int examineclause = 0; while(1) { int cmd = dav_debug_ql_command(); switch (cmd) { case DQLD_CMD_Q: return; case DQLD_CMD_PS: dav_debug_ql_stmt_print(stmt); break; case DQLD_CMD_PE: dav_debug_ql_expr_print(examineexpr); break; case DQLD_CMD_PT: dav_debug_ql_tree_print(examineexpr, 1); break; case DQLD_CMD_PF: dav_debug_ql_fnames_print(stmt); break; case DQLD_CMD_F: if (examineclause != DQLD_CMD_F) { examineclause = DQLD_CMD_F; examineelem = stmt->fields; examineexpr = stmt->fields ? ((DavQLField*)stmt->fields->data)->expr : NULL; dav_debug_ql_expr_print(examineexpr); } break; case DQLD_CMD_W: examineclause = 0; examineelem = NULL; examineexpr = stmt->where; dav_debug_ql_expr_print(examineexpr); break; case DQLD_CMD_O: if (examineclause != DQLD_CMD_O) { examineclause = DQLD_CMD_O; examineelem = stmt->orderby; examineexpr = stmt->orderby ? ((DavQLOrderCriterion*)stmt->orderby->data)->column : NULL; dav_debug_ql_expr_print(examineexpr); } break; case DQLD_CMD_N: case DQLD_CMD_P: if (examineelem) { UcxList *newelem = (cmd == DQLD_CMD_N ? examineelem->next : examineelem->prev); if (newelem) { examineelem = newelem; if (examineclause == DQLD_CMD_O) { examineexpr = ((DavQLOrderCriterion*) examineelem->data)->column; } else if (examineclause == DQLD_CMD_F) { examineexpr = ((DavQLField*)examineelem->data)->expr; } else { printf("Examining unknown clause type."); } dav_debug_ql_expr_print(examineexpr); } else { printf("Reached end of list.\n"); } } else { printf("Currently not examining an expression list.\n"); } break; case DQLD_CMD_L: if (dav_debug_ql_expr_selected(examineexpr)) { if (examineexpr->left) { examineexpr = examineexpr->left; dav_debug_ql_expr_print(examineexpr); } else { printf("There is no left subtree.\n"); } } break; case DQLD_CMD_R: if (dav_debug_ql_expr_selected(examineexpr)) { if (examineexpr->right) { examineexpr = examineexpr->right; dav_debug_ql_expr_print(examineexpr); } else { printf("There is no right subtree.\n"); } } break; case DQLD_CMD_H: printf( "\nCommands:\n" "ps: print statement information\n" "o: examine order by clause\n" "f: examine field list\n" "pf: print field names\n" "w: examine where clause\n" "n: examine next expression " "(in order by clause or field list)\n" "p: examine previous expression " "(in order by clause or field list)\n" "q: quit\n\n" "\nExpression examination:\n" "pe: print expression information\n" "pt: print full syntax tree of current (sub-)expression\n" "l: enter left subtree\n" "r: enter right subtree\n"); break; default: printf("unknown command\n"); } } } // ------------------------------------------------------------------------ // P A R S E R // ------------------------------------------------------------------------ #define _error_context "(%.*s[->]%.*s%.*s)" #define _error_invalid "invalid statement" #define _error_out_of_memory "out of memory" #define _error_unexpected_token "unexpected token " _error_context #define _error_invalid_token "invalid token " _error_context #define _error_missing_path "expected path " _error_context #define _error_missing_from "expecting FROM keyword " _error_context #define _error_missing_by "expecting BY keyword " _error_context #define _error_missing_as "expecting alias ('as <identifier>') " _error_context #define _error_missing_identifier "expecting identifier " _error_context #define _error_missing_par "missing closed parenthesis " _error_context #define _error_invalid_depth "invalid depth " _error_context #define _error_missing_expr "missing expression " _error_context #define _error_invalid_expr "invalid expression " _error_context #define _error_invalid_unary_op "invalid unary operator " _error_context #define _error_invalid_logical_op "invalid logical operator " _error_context #define _error_invalid_fmtspec "invalid format specifier " _error_context #define _error_invalid_string "string expected " _error_context #define _error_invalid_order_criterion "invalid order criterion " _error_context #define token_sstr(token) (((DavQLToken*)(token)->data)->value) static void dav_error_in_context(int errorcode, const char *errormsg, DavQLStatement *stmt, UcxList *token) { // we try to achieve two things: get as many information as possible // and recover the concrete source string (and not the token strings) sstr_t emptystring = ST(""); sstr_t prev = token->prev ? (token->prev->prev ? token_sstr(token->prev->prev) : token_sstr(token->prev)) : emptystring; sstr_t tokenstr = token_sstr(token); sstr_t next = token->next ? (token->next->next ? token_sstr(token->next->next) : token_sstr(token->next)) : emptystring; int lp = prev.length == 0 ? 0 : tokenstr.ptr-prev.ptr; char *pn = tokenstr.ptr + tokenstr.length; int ln = next.ptr+next.length - pn; stmt->errorcode = errorcode; stmt->errormessage = ucx_sprintf(errormsg, lp, prev.ptr, sfmtarg(tokenstr), ln, pn).ptr; } #define dqlsec_alloc_failed(ptr, stmt) \ if (!(ptr)) do { \ (stmt)->errorcode = DAVQL_ERROR_OUT_OF_MEMORY; \ return 0; \ } while(0) #define dqlsec_malloc(stmt, ptr, type) \ dqlsec_alloc_failed(ptr = malloc(sizeof(type)), stmt) #define dqlsec_mallocz(stmt, ptr, type) \ dqlsec_alloc_failed(ptr = calloc(1, sizeof(type)), stmt) #define dqlsec_list_append_or_free(stmt, list, data) \ do { \ UcxList *_dqlsecbak_ = list; \ list = ucx_list_append(list, data); \ if (!list) { \ free(data); \ data = NULL; \ (stmt)->errorcode = DAVQL_ERROR_OUT_OF_MEMORY; \ list = _dqlsecbak_; \ return 0; \ } \ } while(0) // special symbols are single tokens - the % sign MUST NOT be a special symbol static const char *special_token_symbols = ",()+-*/&|^~=!<>"; static _Bool iskeyword(DavQLToken *token) { sstr_t keywords[] ={ST("select"), ST("set"), ST("from"), ST("at"), ST("as"), ST("where"), ST("anywhere"), ST("like"), ST("unlike"), ST("and"), ST("or"), ST("not"), ST("xor"), ST("with"), ST("infinity"), ST("order"), ST("by"), ST("asc"), ST("desc") }; for (int i = 0 ; i < sizeof(keywords)/sizeof(sstr_t) ; i++) { if (!sstrcasecmp(token->value, keywords[i])) { return 1; } } return 0; } static _Bool islongoperator(DavQLToken *token) { sstr_t operators[] = {ST("and"), ST("or"), ST("not"), ST("xor"), ST("like"), ST("unlike") }; for (int i = 0 ; i < sizeof(operators)/sizeof(sstr_t) ; i++) { if (!sstrcasecmp(token->value, operators[i])) { return 1; } } return 0; } static UcxList* dav_parse_add_token(UcxList *tokenlist, DavQLToken *token) { // determine token class (order of if-statements is very important!) char firstchar = token->value.ptr[0]; if (isdigit(firstchar)) { token->tokenclass = DAVQL_TOKEN_NUMBER; // check, if all characters are digits for (size_t i = 1 ; i < token->value.length ; i++) { if (!isdigit(token->value.ptr[i])) { token->tokenclass = DAVQL_TOKEN_INVALID; break; } } } else if (firstchar == '%') { token->tokenclass = DAVQL_TOKEN_FMTSPEC; } else if (token->value.length == 1) { switch (firstchar) { case '(': token->tokenclass = DAVQL_TOKEN_OPENP; break; case ')': token->tokenclass = DAVQL_TOKEN_CLOSEP; break; case ',': token->tokenclass = DAVQL_TOKEN_COMMA; break; default: token->tokenclass = strchr(special_token_symbols, firstchar) ? DAVQL_TOKEN_OPERATOR : DAVQL_TOKEN_IDENTIFIER; } } else if (islongoperator(token)) { token->tokenclass = DAVQL_TOKEN_OPERATOR; } else if (firstchar == '\'') { token->tokenclass = DAVQL_TOKEN_STRING; } else if (firstchar == '`') { token->tokenclass = DAVQL_TOKEN_IDENTIFIER; } else if (iskeyword(token)) { token->tokenclass = DAVQL_TOKEN_KEYWORD; } else { token->tokenclass = DAVQL_TOKEN_IDENTIFIER; // TODO: check for illegal characters } // remove quotes (extreme cool feature) if (token->tokenclass == DAVQL_TOKEN_STRING || (token->tokenclass == DAVQL_TOKEN_IDENTIFIER && firstchar == '`')) { char lastchar = token->value.ptr[token->value.length-1]; if (firstchar == lastchar) { token->value.ptr++; token->value.length -= 2; } else { token->tokenclass = DAVQL_TOKEN_INVALID; } } UcxList *ret = ucx_list_append(tokenlist, token); if (ret) { return ret; } else { ucx_list_free(tokenlist); return NULL; } } static UcxList* dav_parse_tokenize(sstr_t src) { #define alloc_token() do {token = malloc(sizeof(DavQLToken));\ if(!token) {ucx_list_free(tokens); return NULL;}} while(0) #define add_token() do {tokens = dav_parse_add_token(tokens, token); \ if(!tokens) {return NULL;}} while(0) UcxList *tokens = NULL; DavQLToken *token = NULL; char insequence = '\0'; for (size_t i = 0 ; i < src.length ; i++) { // quoted strings / identifiers are a single token if (src.ptr[i] == '\'' || src.ptr[i] == '`') { if (src.ptr[i] == insequence) { // lookahead for escaped string quotes if (src.ptr[i] == '\'' && i+2 < src.length && src.ptr[i+1] == src.ptr[i] && src.ptr[i+2] == src.ptr[i]) { token->value.length += 3; i += 2; } else { // add quoted token to list token->value.length++; add_token(); token = NULL; insequence = '\0'; } } else if (insequence == '\0') { insequence = src.ptr[i]; // always create new token for quoted strings if (token) { add_token(); } alloc_token(); token->value.ptr = src.ptr + i; token->value.length = 1; } else { // add other kind of quotes to token token->value.length++; } } else if (insequence) { token->value.length++; } else if (isspace(src.ptr[i])) { // add token before spaces to list (if any) if (token) { add_token(); token = NULL; } } else if (strchr(special_token_symbols, src.ptr[i])) { // add token before special symbol to list (if any) if (token) { add_token(); token = NULL; } // add special symbol as single token to list alloc_token(); token->value.ptr = src.ptr + i; token->value.length = 1; add_token(); // set tokenizer ready to read more tokens token = NULL; } else { // if this is a new token, create memory for it if (!token) { alloc_token(); token->value.ptr = src.ptr + i; token->value.length = 0; } // extend token length when reading more bytes token->value.length++; } } if (token) { add_token(); } alloc_token(); token->tokenclass = DAVQL_TOKEN_END; token->value = S(""); UcxList *ret = ucx_list_append(tokens, token); if (ret) { return ret; } else { ucx_list_free(tokens); return NULL; } #undef alloc_token #undef add_token } static void dav_free_expression(DavQLExpression *expr) { if (expr) { if (expr->left) { dav_free_expression(expr->left); } if (expr->right) { dav_free_expression(expr->right); } free(expr); } } static void dav_free_field(DavQLField *field) { dav_free_expression(field->expr); free(field); } static void dav_free_order_criterion(DavQLOrderCriterion *crit) { if (crit->column) { // do it null-safe though column is expected to be set dav_free_expression(crit->column); } free(crit); } #define token_is(token, expectedclass) (token && \ (((DavQLToken*)(token)->data)->tokenclass == expectedclass)) #define tokenvalue_is(token, expectedvalue) (token && \ !sstrcasecmp(((DavQLToken*)(token)->data)->value, S(expectedvalue))) typedef int(*exprparser_f)(DavQLStatement*,UcxList*,DavQLExpression*); static int dav_parse_binary_expr(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr, exprparser_f parseL, char* opc, int* opv, exprparser_f parseR) { if (!token) { return 0; } int total_consumed = 0, consumed; // save temporarily on stack (copy to heap later on) DavQLExpression left, right; // RULE: LEFT, [Operator, RIGHT] memset(&left, 0, sizeof(DavQLExpression)); consumed = parseL(stmt, token, &left); if (!consumed || stmt->errorcode) { return 0; } total_consumed += consumed; token = ucx_list_get(token, consumed); char *op; if (token_is(token, DAVQL_TOKEN_OPERATOR) && (op = strchr(opc, token_sstr(token).ptr[0]))) { expr->op = opv[op-opc]; expr->type = DAVQL_BINARY; total_consumed++; token = token->next; memset(&right, 0, sizeof(DavQLExpression)); consumed = parseR(stmt, token, &right); if (stmt->errorcode) { return 0; } if (!consumed) { dav_error_in_context(DAVQL_ERROR_MISSING_EXPR, _error_missing_expr, stmt, token); return 0; } total_consumed += consumed; } if (expr->op == DAVQL_NOOP) { memcpy(expr, &left, sizeof(DavQLExpression)); } else { dqlsec_malloc(stmt, expr->left, DavQLExpression); memcpy(expr->left, &left, sizeof(DavQLExpression)); dqlsec_malloc(stmt, expr->right, DavQLExpression); memcpy(expr->right, &right, sizeof(DavQLExpression)); expr->srctext.ptr = expr->left->srctext.ptr; expr->srctext.length = expr->right->srctext.ptr - expr->left->srctext.ptr + expr->right->srctext.length; } return total_consumed; } static int dav_parse_literal(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { expr->srctext = token_sstr(token); if (token_is(token, DAVQL_TOKEN_NUMBER)) { expr->type = DAVQL_NUMBER; } else if (token_is(token, DAVQL_TOKEN_STRING)) { expr->type = DAVQL_STRING; } else if (token_is(token, DAVQL_TOKEN_TIMESTAMP)) { expr->type = DAVQL_TIMESTAMP; } else if (token_is(token, DAVQL_TOKEN_FMTSPEC) && expr->srctext.length == 2) { switch (expr->srctext.ptr[1]) { case 'd': expr->type = DAVQL_NUMBER; break; case 's': expr->type = DAVQL_STRING; break; case 't': expr->type = DAVQL_TIMESTAMP; break; default: dav_error_in_context(DAVQL_ERROR_INVALID_FMTSPEC, _error_invalid_fmtspec, stmt, token); return 0; } } else { return 0; } return 1; } // forward declaration static int dav_parse_expression(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr); static int dav_parse_arglist(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { expr->srctext.ptr = token_sstr(token).ptr; expr->srctext.length = 0; expr->left = expr->right = NULL; // in case we fail, we want them to be sane int total_consumed = 0; // RULE: Expression, {",", Expression}; DavQLExpression *arglist = expr; DavQLExpression arg; char *lastchar = expr->srctext.ptr; int consumed; do { memset(&arg, 0, sizeof(DavQLExpression)); consumed = dav_parse_expression(stmt, token, &arg); if (consumed) { lastchar = arg.srctext.ptr + arg.srctext.length; total_consumed += consumed; token = ucx_list_get(token, consumed); // look ahead for a comma if (token_is(token, DAVQL_TOKEN_COMMA)) { total_consumed++; token = token->next; /* we have more arguments, so put the current argument to the * left subtree and create a new node to the right */ dqlsec_malloc(stmt, arglist->left, DavQLExpression); memcpy(arglist->left, &arg, sizeof(DavQLExpression)); arglist->srctext.ptr = arg.srctext.ptr; arglist->op = DAVQL_ARGLIST; arglist->type = DAVQL_FUNCCALL; dqlsec_mallocz(stmt, arglist->right, DavQLExpression); arglist = arglist->right; } else { // this was the last argument, so write it to the current node memcpy(arglist, &arg, sizeof(DavQLExpression)); consumed = 0; } } } while (consumed && !stmt->errorcode); // recover source text arglist = expr; while (arglist && arglist->type == DAVQL_FUNCCALL) { arglist->srctext.length = lastchar - arglist->srctext.ptr; arglist = arglist->right; } return total_consumed; } static int dav_parse_funccall(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { // RULE: Identifier, "(", ArgumentList, ")"; if (token_is(token, DAVQL_TOKEN_IDENTIFIER) && token_is(token->next, DAVQL_TOKEN_OPENP)) { expr->type = DAVQL_FUNCCALL; expr->op = DAVQL_CALL; dqlsec_mallocz(stmt, expr->left, DavQLExpression); expr->left->type = DAVQL_IDENTIFIER; expr->left->srctext = token_sstr(token); expr->right = NULL; token = token->next->next; DavQLExpression arg; int argtokens = dav_parse_arglist(stmt, token, &arg); if (stmt->errorcode) { // if an error occurred while parsing the arglist, return now return 2; } if (argtokens) { token = ucx_list_get(token, argtokens); dqlsec_malloc(stmt, expr->right, DavQLExpression); memcpy(expr->right, &arg, sizeof(DavQLExpression)); } else { // arg list may be empty expr->right = NULL; } if (token_is(token, DAVQL_TOKEN_CLOSEP)) { return 3 + argtokens; } else { dav_error_in_context(DAVQL_ERROR_MISSING_PAR, _error_missing_par, stmt, token); return 2; // it MUST be a function call, but it is invalid } } else { return 0; } } static int dav_parse_unary_expr(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { UcxList *firsttoken = token; // save for srctext recovery DavQLExpression* atom = expr; int total_consumed = 0; // optional unary operator if (token_is(token, DAVQL_TOKEN_OPERATOR)) { char *op = strchr("+-~", token_sstr(token).ptr[0]); if (op) { expr->type = DAVQL_UNARY; switch (*op) { case '+': expr->op = DAVQL_ADD; break; case '-': expr->op = DAVQL_SUB; break; case '~': expr->op = DAVQL_NEG; break; } dqlsec_mallocz(stmt, expr->left, DavQLExpression); atom = expr->left; total_consumed++; token = token->next; } else { dav_error_in_context(DAVQL_ERROR_INVALID_UNARY_OP, _error_invalid_unary_op, stmt, token); return 0; } } // RULE: (ParExpression | AtomicExpression) if (token_is(token, DAVQL_TOKEN_OPENP)) { token = token->next; total_consumed++; // RULE: "(", Expression, ")" int consumed = dav_parse_expression(stmt, token, atom); if (stmt->errorcode) { return 0; } if (!consumed) { dav_error_in_context(DAVQL_ERROR_INVALID_EXPR, _error_invalid_expr, stmt, token); return 0; } token = ucx_list_get(token, consumed); total_consumed += consumed; if (token_is(token, DAVQL_TOKEN_CLOSEP)) { token = token->next; total_consumed++; } else { dav_error_in_context(DAVQL_ERROR_MISSING_PAR, _error_missing_par, stmt, token); return 0; } } else { // RULE: FunctionCall int consumed = dav_parse_funccall(stmt, token, atom); if (consumed) { total_consumed += consumed; } else if (token_is(token, DAVQL_TOKEN_IDENTIFIER)) { // RULE: Identifier total_consumed++; atom->type = DAVQL_IDENTIFIER; atom->srctext = token_sstr(token); } else { // RULE: Literal total_consumed += dav_parse_literal(stmt, token, atom); } } // recover source text expr->srctext.ptr = token_sstr(firsttoken).ptr; if (total_consumed > 0) { sstr_t lasttoken = token_sstr(ucx_list_get(firsttoken, total_consumed-1)); expr->srctext.length = lasttoken.ptr - expr->srctext.ptr + lasttoken.length; } else { // the expression should not be used anyway, but we want to be safe expr->srctext.length = 0; } return total_consumed; } static int dav_parse_bitexpr(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { return dav_parse_binary_expr(stmt, token, expr, dav_parse_unary_expr, "&|^", (int[]){DAVQL_AND, DAVQL_OR, DAVQL_XOR}, dav_parse_bitexpr); } static int dav_parse_multexpr(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { return dav_parse_binary_expr(stmt, token, expr, dav_parse_bitexpr, "*/", (int[]){DAVQL_MUL, DAVQL_DIV}, dav_parse_multexpr); } static int dav_parse_expression(DavQLStatement* stmt, UcxList* token, DavQLExpression* expr) { return dav_parse_binary_expr(stmt, token, expr, dav_parse_multexpr, "+-", (int[]){DAVQL_ADD, DAVQL_SUB}, dav_parse_expression); } static int dav_parse_named_field(DavQLStatement *stmt, UcxList *token, DavQLField *field) { int total_consumed = 0, consumed; // RULE: Expression, " as ", Identifier; DavQLExpression *expr; dqlsec_mallocz(stmt, expr, DavQLExpression); consumed = dav_parse_expression(stmt, token, expr); if (stmt->errorcode) { dav_free_expression(expr); return 0; } if (expr->type == DAVQL_UNDEFINED_TYPE) { dav_free_expression(expr); dav_error_in_context(DAVQL_ERROR_INVALID_EXPR, _error_invalid_expr, stmt, token); return 0; } token = ucx_list_get(token, consumed); total_consumed += consumed; if (token_is(token, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(token, "as")) { token = token->next; total_consumed++; } else { dav_free_expression(expr); dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN, _error_missing_as, stmt, token); return 0; } if (token_is(token, DAVQL_TOKEN_IDENTIFIER)) { field->name = token_sstr(token); field->expr = expr; return total_consumed + 1; } else { dav_free_expression(expr); dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN, _error_missing_identifier, stmt, token); return 0; } } static int dav_parse_fieldlist(DavQLStatement *stmt, UcxList *token) { // RULE: "-" if (token_is(token, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(token, "-")) { DavQLField *field; dqlsec_malloc(stmt, field, DavQLField); dqlsec_list_append_or_free(stmt, stmt->fields, field); dqlsec_mallocz(stmt, field->expr, DavQLExpression); field->expr->type = DAVQL_IDENTIFIER; field->expr->srctext = field->name = token_sstr(token); return 1; } // RULE: "*", {",", NamedExpression} if (token_is(token, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(token, "*")) { DavQLField *field; dqlsec_malloc(stmt, field, DavQLField); dqlsec_list_append_or_free(stmt, stmt->fields, field); dqlsec_mallocz(stmt, field->expr, DavQLExpression); field->expr->type = DAVQL_IDENTIFIER; field->expr->srctext = field->name = token_sstr(token); int total_consumed = 0; int consumed = 1; do { token = ucx_list_get(token, consumed); total_consumed += consumed; if (token_is(token, DAVQL_TOKEN_COMMA)) { total_consumed++; token = token->next; DavQLField localfield; consumed = dav_parse_named_field(stmt, token, &localfield); if (!stmt->errorcode && consumed) { DavQLField *field; dqlsec_malloc(stmt, field, DavQLField); memcpy(field, &localfield, sizeof(DavQLField)); dqlsec_list_append_or_free(stmt, stmt->fields, field); } } else { consumed = 0; } } while (consumed > 0); return total_consumed; } // RULE: FieldExpression, {",", FieldExpression} { int total_consumed = 0, consumed; do { // RULE: NamedField | Identifier DavQLField localfield; consumed = dav_parse_named_field(stmt, token, &localfield); if (consumed) { DavQLField *field; dqlsec_malloc(stmt, field, DavQLField); memcpy(field, &localfield, sizeof(DavQLField)); dqlsec_list_append_or_free(stmt, stmt->fields, field); token = ucx_list_get(token, consumed); total_consumed += consumed; } else if (token_is(token, DAVQL_TOKEN_IDENTIFIER) // look ahead, if the field is JUST the identifier && (token_is(token->next, DAVQL_TOKEN_COMMA) || tokenvalue_is(token->next, "from"))) { DavQLField *field; dqlsec_malloc(stmt, field, DavQLField); dqlsec_mallocz(stmt, field->expr, DavQLExpression); field->expr->type = DAVQL_IDENTIFIER; field->expr->srctext = field->name = token_sstr(token); dqlsec_list_append_or_free(stmt, stmt->fields, field); consumed = 1; total_consumed++; token = token->next; // we found a valid solution, so erase any errors stmt->errorcode = 0; if (stmt->errormessage) { free(stmt->errormessage); stmt->errormessage = NULL; } } else { // dav_parse_named_field has already thrown a good error consumed = 0; } // field has been parsed, now try to get a comma if (consumed) { consumed = token_is(token, DAVQL_TOKEN_COMMA) ? 1 : 0; if (consumed) { token = token->next; total_consumed++; } } } while (consumed); return total_consumed; } } // forward declaration static int dav_parse_logical_expr(DavQLStatement *stmt, UcxList *token, DavQLExpression *expr); static int dav_parse_bool_prim(DavQLStatement *stmt, UcxList *token, DavQLExpression *expr) { expr->type = DAVQL_LOGICAL; expr->srctext = token_sstr(token); int total_consumed = 0; DavQLExpression bexpr; memset(&bexpr, 0, sizeof(DavQLExpression)); total_consumed = dav_parse_expression(stmt, token, &bexpr); if (!total_consumed || stmt->errorcode) { return 0; } token = ucx_list_get(token, total_consumed); UcxList* optok = token; // RULE: Expression, (" like " | " unlike "), String if (token_is(optok, DAVQL_TOKEN_OPERATOR) && (tokenvalue_is(optok, "like") || tokenvalue_is(optok, "unlike"))) { total_consumed++; token = token->next; if (token_is(token, DAVQL_TOKEN_STRING)) { expr->op = tokenvalue_is(optok, "like") ? DAVQL_LIKE : DAVQL_UNLIKE; dqlsec_malloc(stmt, expr->left, DavQLExpression); memcpy(expr->left, &bexpr, sizeof(DavQLExpression)); dqlsec_mallocz(stmt, expr->right, DavQLExpression); expr->right->type = DAVQL_STRING; expr->right->srctext = token_sstr(token); expr->srctext.length = expr->right->srctext.ptr - expr->srctext.ptr + expr->right->srctext.length; return total_consumed + 1; } else { dav_error_in_context(DAVQL_ERROR_INVALID_STRING, _error_invalid_string, stmt, token); return 0; } } // RULE: Expression, Comparison, Expression else if (token_is(optok, DAVQL_TOKEN_OPERATOR) && ( tokenvalue_is(optok, "=") || tokenvalue_is(optok, "!") || tokenvalue_is(optok, "<") || tokenvalue_is(optok, ">"))) { total_consumed++; token = token->next; if (tokenvalue_is(optok, "=")) { expr->op = DAVQL_EQ; } else { if (tokenvalue_is(token, "=")) { if (tokenvalue_is(optok, "!")) { expr->op = DAVQL_NEQ; } else if (tokenvalue_is(optok, "<")) { expr->op = DAVQL_LE; } else if (tokenvalue_is(optok, ">")) { expr->op = DAVQL_GE; } total_consumed++; token = token->next; } else { if (tokenvalue_is(optok, "<")) { expr->op = DAVQL_LT; } else if (tokenvalue_is(optok, ">")) { expr->op = DAVQL_GT; } } } DavQLExpression rexpr; memset(&rexpr, 0, sizeof(DavQLExpression)); int consumed = dav_parse_expression(stmt, token, &rexpr); if (stmt->errorcode) { return 0; } if (!consumed) { dav_error_in_context( DAVQL_ERROR_MISSING_EXPR, _error_missing_expr, stmt, token); return 0; } total_consumed += consumed; dqlsec_malloc(stmt, expr->left, DavQLExpression); memcpy(expr->left, &bexpr, sizeof(DavQLExpression)); dqlsec_malloc(stmt, expr->right, DavQLExpression); memcpy(expr->right, &rexpr, sizeof(DavQLExpression)); expr->srctext.length = expr->right->srctext.ptr - expr->srctext.ptr + expr->right->srctext.length; return total_consumed; } // RULE: FunctionCall | Identifier; else if (bexpr.type == DAVQL_FUNCCALL || bexpr.type == DAVQL_IDENTIFIER) { memcpy(expr, &bexpr, sizeof(DavQLExpression)); return total_consumed; } else { return 0; } } static int dav_parse_bool_expr(DavQLStatement *stmt, UcxList *token, DavQLExpression *expr) { // RULE: "not ", LogicalExpression if (token_is(token, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(token, "not")) { expr->type = DAVQL_LOGICAL; expr->op = DAVQL_NOT; dqlsec_mallocz(stmt, expr->left, DavQLExpression); expr->srctext = token_sstr(token); token = token->next; int consumed = dav_parse_bool_expr(stmt, token, expr->left); if (stmt->errorcode) { return 0; } if (consumed) { sstr_t lasttok = token_sstr(ucx_list_get(token, consumed-1)); expr->srctext.length = lasttok.ptr - expr->srctext.ptr + lasttok.length; return consumed + 1; } else { dav_error_in_context(DAVQL_ERROR_MISSING_EXPR, _error_missing_expr, stmt, token); return 0; } } // RULE: "(", LogicalExpression, ")" else if (token_is(token, DAVQL_TOKEN_OPENP)) { int consumed = dav_parse_logical_expr(stmt, token->next, expr); if (consumed) { token = ucx_list_get(token->next, consumed); if (token_is(token, DAVQL_TOKEN_CLOSEP)) { token = token->next; return consumed + 2; } else { dav_error_in_context(DAVQL_ERROR_MISSING_PAR, _error_missing_par, stmt, token); return 0; } } else { // don't handle errors here, we can also try a boolean primary stmt->errorcode = 0; if (stmt->errormessage) { free(stmt->errormessage); } } } // RULE: BooleanPrimary return dav_parse_bool_prim(stmt, token, expr); } static int dav_parse_logical_expr(DavQLStatement *stmt, UcxList *token, DavQLExpression *expr) { UcxList *firsttoken = token; int total_consumed = 0; // RULE: BooleanLiteral, [LogicalOperator, LogicalExpression]; DavQLExpression left, right; memset(&left, 0, sizeof(DavQLExpression)); int consumed = dav_parse_bool_expr(stmt, token, &left); if (stmt->errorcode) { return 0; } if (!consumed) { dav_error_in_context(DAVQL_ERROR_MISSING_EXPR, _error_missing_expr, stmt, token); return 0; } total_consumed += consumed; token = ucx_list_get(token, consumed); if (token_is(token, DAVQL_TOKEN_OPERATOR)) { expr->type = DAVQL_LOGICAL; davqloperator_t op = DAVQL_NOOP; if (tokenvalue_is(token, "and")) { op = DAVQL_LAND; } else if (tokenvalue_is(token, "or")) { op = DAVQL_LOR; } else if (tokenvalue_is(token, "xor")) { op = DAVQL_LXOR; } if (op == DAVQL_NOOP) { dav_error_in_context(DAVQL_ERROR_INVALID_LOGICAL_OP, _error_invalid_logical_op, stmt, token); return 0; } else { expr->op = op; total_consumed++; token = token->next; memset(&right, 0, sizeof(DavQLExpression)); consumed = dav_parse_logical_expr(stmt, token, &right); if (stmt->errorcode) { return 0; } if (!consumed) { dav_error_in_context(DAVQL_ERROR_MISSING_EXPR, _error_missing_expr, stmt, token); return 0; } total_consumed += consumed; token = ucx_list_get(token, consumed); dqlsec_malloc(stmt, expr->left, DavQLExpression); memcpy(expr->left, &left, sizeof(DavQLExpression)); dqlsec_malloc(stmt, expr->right, DavQLExpression); memcpy(expr->right, &right, sizeof(DavQLExpression)); } } else { memcpy(expr, &left, sizeof(DavQLExpression)); } // set type and recover source text if (total_consumed > 0) { expr->srctext.ptr = token_sstr(firsttoken).ptr; sstr_t lasttok = token_sstr(ucx_list_get(firsttoken, total_consumed-1)); expr->srctext.length = lasttok.ptr-expr->srctext.ptr+lasttok.length; } return total_consumed; } static int dav_parse_where_clause(DavQLStatement *stmt, UcxList *token) { dqlsec_mallocz(stmt, stmt->where, DavQLExpression); return dav_parse_logical_expr(stmt, token, stmt->where); } static int dav_parse_with_clause(DavQLStatement *stmt, UcxList *token) { int total_consumed = 0; // RULE: "depth", "=", (Number | "infinity") if (tokenvalue_is(token, "depth")) { token = token->next; total_consumed++; if (tokenvalue_is(token, "=")) { token = token->next; total_consumed++; if (tokenvalue_is(token, "infinity")) { stmt->depth = DAV_DEPTH_INFINITY; token = token->next; total_consumed++; } else { DavQLExpression *depthexpr; dqlsec_mallocz(stmt, depthexpr, DavQLExpression); int consumed = dav_parse_expression(stmt, token, depthexpr); if (consumed) { if (depthexpr->type == DAVQL_NUMBER) { if (depthexpr->srctext.ptr[0] == '%') { stmt->depth = DAV_DEPTH_PLACEHOLDER; } else { sstr_t depthstr = depthexpr->srctext; char *conv = malloc(depthstr.length+1); if (!conv) { dav_free_expression(depthexpr); stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY; return 0; } char *chk; memcpy(conv, depthstr.ptr, depthstr.length); conv[depthstr.length] = '\0'; stmt->depth = strtol(conv, &chk, 10); if (*chk || stmt->depth < -1) { dav_error_in_context(DAVQL_ERROR_INVALID_DEPTH, _error_invalid_depth, stmt, token); } free(conv); } total_consumed += consumed; } else { dav_error_in_context(DAVQL_ERROR_INVALID_DEPTH, _error_invalid_depth, stmt, token); } } dav_free_expression(depthexpr); } } } return total_consumed; } static int dav_parse_order_crit(DavQLStatement *stmt, UcxList *token, DavQLOrderCriterion *crit) { // RULE: (Identifier | Number), [" asc"|" desc"]; DavQLExpression expr; memset(&expr, 0, sizeof(DavQLExpression)); int consumed = dav_parse_expression(stmt, token, &expr); if (stmt->errorcode || !consumed) { return 0; } if (expr.type != DAVQL_IDENTIFIER && expr.type != DAVQL_NUMBER) { dav_error_in_context(DAVQL_ERROR_INVALID_ORDER_CRITERION, _error_invalid_order_criterion, stmt, token); return 0; } dqlsec_malloc(stmt, crit->column, DavQLExpression); memcpy(crit->column, &expr, sizeof(DavQLExpression)); token = ucx_list_get(token, consumed); if (token_is(token, DAVQL_TOKEN_KEYWORD) && ( tokenvalue_is(token, "asc") || tokenvalue_is(token, "desc"))) { crit->descending = tokenvalue_is(token, "desc"); return consumed+1; } else { crit->descending = 0; return consumed; } } static int dav_parse_orderby_clause(DavQLStatement *stmt, UcxList *token) { int total_consumed = 0, consumed; DavQLOrderCriterion crit; // RULE: OrderByCriterion, {",", OrderByCriterion}; do { consumed = dav_parse_order_crit(stmt, token, &crit); if (stmt->errorcode) { return 0; } if (!consumed) { dav_error_in_context(DAVQL_ERROR_MISSING_EXPR, _error_missing_expr, stmt, token); return 0; } token = ucx_list_get(token, consumed); total_consumed += consumed; DavQLOrderCriterion *criterion; dqlsec_malloc(stmt, criterion, DavQLOrderCriterion); memcpy(criterion, &crit, sizeof(DavQLOrderCriterion)); dqlsec_list_append_or_free(stmt, stmt->orderby, criterion); if (token_is(token, DAVQL_TOKEN_COMMA)) { total_consumed++; token = token->next; } else { consumed = 0; } } while (consumed); return total_consumed; } /** * Parser of a select statement. * @param stmt the statement object that shall contain the syntax tree * @param tokens the token list */ static void dav_parse_select_statement(DavQLStatement *stmt, UcxList *tokens) { stmt->type = DAVQL_SELECT; // Consume field list tokens = ucx_list_get(tokens, dav_parse_fieldlist(stmt, tokens)); if (stmt->errorcode) { return; } // Consume from keyword if (token_is(tokens, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(tokens, "from")) { tokens = tokens->next; } else { dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN, _error_missing_from, stmt, tokens); return; } // Consume path if (token_is(tokens, DAVQL_TOKEN_STRING)) { stmt->path = token_sstr(tokens); tokens = tokens->next; } else if (token_is(tokens, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(tokens, "/")) { stmt->path = token_sstr(tokens); tokens = tokens->next; while (!token_is(tokens, DAVQL_TOKEN_KEYWORD) && !token_is(tokens, DAVQL_TOKEN_END)) { sstr_t toksstr = token_sstr(tokens); stmt->path.length = toksstr.ptr-stmt->path.ptr+toksstr.length; tokens = tokens->next; } } else if (token_is(tokens, DAVQL_TOKEN_FMTSPEC) && tokenvalue_is(tokens, "%s")) { stmt->path = token_sstr(tokens); tokens = tokens->next; } else { dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN, _error_missing_path, stmt, tokens); return; } // Consume with clause (if any) if (token_is(tokens, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(tokens, "with")) { tokens = tokens->next; tokens = ucx_list_get(tokens, dav_parse_with_clause(stmt, tokens)); } if (stmt->errorcode) { return; } // Consume where clause (if any) if (token_is(tokens, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(tokens, "where")) { tokens = tokens->next; tokens = ucx_list_get(tokens, dav_parse_where_clause(stmt, tokens)); } if (stmt->errorcode) { return; } // Consume order by clause (if any) if (token_is(tokens, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(tokens, "order")) { tokens = tokens->next; if (token_is(tokens, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(tokens, "by")) { tokens = tokens->next; tokens = ucx_list_get(tokens, dav_parse_orderby_clause(stmt, tokens)); } else { dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN, _error_missing_by, stmt, tokens); return; } } if (stmt->errorcode) { return; } if (tokens) { if (token_is(tokens, DAVQL_TOKEN_INVALID)) { dav_error_in_context(DAVQL_ERROR_INVALID_TOKEN, _error_invalid_token, stmt, tokens); } else if (!token_is(tokens, DAVQL_TOKEN_END)) { dav_error_in_context(DAVQL_ERROR_UNEXPECTED_TOKEN, _error_unexpected_token, stmt, tokens); } } } static void dav_parse_set_statement(DavQLStatement *stmt, UcxList *tokens) { stmt->type = DAVQL_SET; // TODO: make it so } DavQLStatement* dav_parse_statement(sstr_t srctext) { DavQLStatement *stmt = calloc(1, sizeof(DavQLStatement)); // if we can't even get enough memory for the statement object or an error // message, we can simply die without returning anything if (!stmt) { return NULL; } char *oommsg = strdup(_error_out_of_memory); if (!oommsg) { free(stmt); return NULL; } // default values stmt->type = -1; stmt->depth = 1; // save trimmed source text stmt->srctext = sstrtrim(srctext); if (stmt->srctext.length) { // tokenization UcxList* tokens = dav_parse_tokenize(stmt->srctext); if (tokens) { // use first token to determine query type if (tokenvalue_is(tokens, "select")) { dav_parse_select_statement(stmt, tokens->next); } else if (tokenvalue_is(tokens, "set")) { dav_parse_set_statement(stmt, tokens->next); } else { stmt->type = DAVQL_ERROR; stmt->errorcode = DAVQL_ERROR_INVALID; stmt->errormessage = strdup(_error_invalid); } // free token data UCX_FOREACH(token, tokens) { free(token->data); } ucx_list_free(tokens); } else { stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY; } } else { stmt->type = DAVQL_ERROR; stmt->errorcode = DAVQL_ERROR_INVALID; stmt->errormessage = strdup(_error_invalid); } if (stmt->errorcode == DAVQL_ERROR_OUT_OF_MEMORY) { stmt->type = DAVQL_ERROR; stmt->errormessage = oommsg; } else { free(oommsg); } return stmt; } void dav_free_statement(DavQLStatement *stmt) { UCX_FOREACH(expr, stmt->fields) { dav_free_field(expr->data); } ucx_list_free(stmt->fields); if (stmt->where) { dav_free_expression(stmt->where); } if (stmt->errormessage) { free(stmt->errormessage); } UCX_FOREACH(crit, stmt->orderby) { dav_free_order_criterion(crit->data); } ucx_list_free(stmt->orderby); free(stmt); }
