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comparison: libidav/davqlparser.c

libidav/davqlparser.c

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1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2018 Olaf Wintermann. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "davqlparser.h"
30 #include <cx/utils.h>
31 #include <cx/linked_list.h>
32 #include <cx/printf.h>
33 #include <string.h>
34 #include <stdio.h>
35 #include <ctype.h>
36
37 #define sfmtarg(s) ((int)(s).length), (s).ptr
38
39 // ------------------------------------------------------------------------
40 // D E B U G E R
41 // ------------------------------------------------------------------------
42
43 static const char* _map_querytype(davqltype_t type) {
44 switch(type) {
45 case DAVQL_ERROR: return "ERROR";
46 case DAVQL_SELECT: return "SELECT";
47 case DAVQL_SET: return "SET";
48 default: return "unknown";
49 }
50 }
51
52 static const char* _map_exprtype(davqlexprtype_t type) {
53 switch(type) {
54 case DAVQL_UNDEFINED_TYPE: return "undefined";
55 case DAVQL_NUMBER: return "NUMBER";
56 case DAVQL_STRING: return "STRING";
57 case DAVQL_TIMESTAMP: return "TIMESTAMP";
58 case DAVQL_IDENTIFIER: return "IDENTIFIER";
59 case DAVQL_UNARY: return "UNARY";
60 case DAVQL_BINARY: return "BINARY";
61 case DAVQL_LOGICAL: return "LOGICAL";
62 case DAVQL_FUNCCALL: return "FUNCCALL";
63 default: return "unknown";
64 }
65 }
66
67 static const char* _map_specialfield(int info) {
68 switch(info) {
69 case 0: return "";
70 case 1: return "with wildcard";
71 case 2: return "(resource data only)";
72 default: return "with mysterious identifier";
73 }
74 }
75
76 static const char* _map_operator(davqloperator_t op) {
77 // don't use string array, because enum values may change
78 switch(op) {
79 case DAVQL_NOOP: return "no operator";
80 case DAVQL_CALL: return "function call"; case DAVQL_ARGLIST: return ",";
81 case DAVQL_ADD: return "+"; case DAVQL_SUB: return "-";
82 case DAVQL_MUL: return "*"; case DAVQL_DIV: return "/";
83 case DAVQL_AND: return "&"; case DAVQL_OR: return "|";
84 case DAVQL_XOR: return "^"; case DAVQL_NEG: return "~";
85 case DAVQL_NOT: return "NOT"; case DAVQL_LAND: return "AND";
86 case DAVQL_LOR: return "OR"; case DAVQL_LXOR: return "XOR";
87 case DAVQL_EQ: return "="; case DAVQL_NEQ: return "!=";
88 case DAVQL_LT: return "<"; case DAVQL_GT: return ">";
89 case DAVQL_LE: return "<="; case DAVQL_GE: return ">=";
90 case DAVQL_LIKE: return "LIKE"; case DAVQL_UNLIKE: return "UNLIKE";
91 default: return "unknown";
92 }
93 }
94
95 static void dav_debug_ql_fnames_print(DavQLStatement *stmt) {
96 if (stmt->fields) {
97 printf("Field names: ");
98 CxIterator i = cxListIterator(stmt->fields);
99 cx_foreach(DavQLField *, f, i) {
100 printf("%.*s, ", (int)f->name.length, f->name.ptr);
101 }
102 printf("\b\b \b\b\n");
103 }
104 }
105
106 static void dav_debug_ql_stmt_print(DavQLStatement *stmt) {
107 // Basic information
108 size_t fieldcount = stmt->fields ? stmt->fields->size : 0;
109 int specialfield = 0;
110 if (stmt->fields && stmt->fields->size > 0) {
111 DavQLField* firstfield = (DavQLField*)cxListAt(stmt->fields, 0);
112 if (firstfield->expr->type == DAVQL_IDENTIFIER) {
113 switch (firstfield->expr->srctext.ptr[0]) {
114 case '*': specialfield = 1; break;
115 case '-': specialfield = 2; break;
116 }
117 }
118 }
119 if (specialfield) {
120 fieldcount--;
121 }
122 printf("Statement: %.*s\nType: %s\nField count: %zu %s\n",
123 (int)stmt->srctext.length, stmt->srctext.ptr,
124 _map_querytype(stmt->type),
125 fieldcount,
126 _map_specialfield(specialfield));
127
128 dav_debug_ql_fnames_print(stmt);
129 printf("Path: %.*s\nHas where clause: %s\n",
130 (int)stmt->path.length, stmt->path.ptr,
131 stmt->where ? "yes" : "no");
132
133 // WITH attributes
134 if (stmt->depth == DAV_DEPTH_INFINITY) {
135 printf("Depth: infinity\n");
136 } else if (stmt->depth == DAV_DEPTH_PLACEHOLDER) {
137 printf("Depth: placeholder\n");
138 } else {
139 printf("Depth: %d\n", stmt->depth);
140 }
141
142 // order by clause
143 printf("Order by: ");
144 if (stmt->orderby) {
145 CxIterator i = cxListIterator(stmt->orderby);
146 cx_foreach(DavQLOrderCriterion*, critdata, i) {
147 printf("%.*s %s%s", (int)critdata->column->srctext.length, critdata->column->srctext.ptr,
148 critdata->descending ? "desc" : "asc",
149 i.index+1 < stmt->orderby->size ? ", " : "\n");
150 }
151 } else {
152 printf("nothing\n");
153 }
154
155 // error messages
156 if (stmt->errorcode) {
157 printf("\nError code: %d\nError: %s\n",
158 stmt->errorcode, stmt->errormessage);
159 }
160 }
161
162 static int dav_debug_ql_expr_selected(DavQLExpression *expr) {
163 if (!expr) {
164 printf("Currently no expression selected.\n");
165 return 0;
166 } else {
167 return 1;
168 }
169 }
170
171 static void dav_debug_ql_expr_print(DavQLExpression *expr) {
172 if (dav_debug_ql_expr_selected(expr)) {
173 cxstring empty = CX_STR("(empty)");
174 printf(
175 "Text: %.*s\nType: %s\nOperator: %s\n",
176 sfmtarg(expr->srctext),
177 _map_exprtype(expr->type),
178 _map_operator(expr->op));
179 if (expr->left || expr->right) {
180 printf("Left hand: %.*s\nRight hand: %.*s\n",
181 sfmtarg(expr->left?expr->left->srctext:empty),
182 sfmtarg(expr->right?expr->right->srctext:empty));
183 }
184 }
185 }
186
187 static void dav_debug_ql_field_print(DavQLField *field) {
188 if (field) {
189 printf("Name: %.*s\n", sfmtarg(field->name));
190 if (field->expr) {
191 dav_debug_ql_expr_print(field->expr);
192 } else {
193 printf("No expression.\n");
194 }
195 } else {
196 printf("No field selected.\n");
197 }
198 }
199
200 static void dav_debug_ql_tree_print(DavQLExpression *expr, int depth) {
201 if (expr) {
202 if (expr->left) {
203 printf("%*c%s\n", depth, ' ', _map_operator(expr->op));
204 dav_debug_ql_tree_print(expr->left, depth+1);
205 dav_debug_ql_tree_print(expr->right, depth+1);
206 } else if (expr->type == DAVQL_UNARY) {
207 printf("%*c%s %.*s\n", depth, ' ', _map_operator(expr->op),
208 sfmtarg(expr->srctext));
209 } else {
210 printf("%*c%.*s\n", depth, ' ', sfmtarg(expr->srctext));
211 }
212 }
213 }
214
215 #define DQLD_CMD_Q 0
216 #define DQLD_CMD_PS 1
217 #define DQLD_CMD_PE 2
218 #define DQLD_CMD_PF 3
219 #define DQLD_CMD_PT 4
220 #define DQLD_CMD_F 10
221 #define DQLD_CMD_W 11
222 #define DQLD_CMD_O 12
223 #define DQLD_CMD_L 21
224 #define DQLD_CMD_R 22
225 #define DQLD_CMD_N 23
226 #define DQLD_CMD_P 24
227 #define DQLD_CMD_H 100
228
229 static int dav_debug_ql_command() {
230 printf("> ");
231
232 char buffer[8];
233 fgets(buffer, 8, stdin);
234 // discard remaining chars
235 if (!strchr(buffer, '\n')) {
236 int chr;
237 while ((chr = fgetc(stdin) != '\n') && chr != EOF);
238 }
239
240 if (!strcmp(buffer, "q\n")) {
241 return DQLD_CMD_Q;
242 } else if (!strcmp(buffer, "ps\n")) {
243 return DQLD_CMD_PS;
244 } else if (!strcmp(buffer, "pe\n")) {
245 return DQLD_CMD_PE;
246 } else if (!strcmp(buffer, "pf\n")) {
247 return DQLD_CMD_PF;
248 } else if (!strcmp(buffer, "pt\n")) {
249 return DQLD_CMD_PT;
250 } else if (!strcmp(buffer, "l\n")) {
251 return DQLD_CMD_L;
252 } else if (!strcmp(buffer, "r\n")) {
253 return DQLD_CMD_R;
254 } else if (!strcmp(buffer, "h\n")) {
255 return DQLD_CMD_H;
256 } else if (!strcmp(buffer, "f\n")) {
257 return DQLD_CMD_F;
258 } else if (!strcmp(buffer, "w\n")) {
259 return DQLD_CMD_W;
260 } else if (!strcmp(buffer, "o\n")) {
261 return DQLD_CMD_O;
262 } else if (!strcmp(buffer, "n\n")) {
263 return DQLD_CMD_N;
264 } else if (!strcmp(buffer, "p\n")) {
265 return DQLD_CMD_P;
266 } else {
267 return -1;
268 }
269 }
270
271 void dav_debug_statement(DavQLStatement *stmt) {
272 if (!stmt) {
273 fprintf(stderr, "Debug DavQLStatement failed: null pointer");
274 return;
275 }
276
277 printf("Starting DavQL debugger (type 'h' for help)...\n\n");
278 dav_debug_ql_stmt_print(stmt);
279
280 if (stmt->errorcode) {
281 return;
282 }
283
284 DavQLExpression *examineexpr = NULL;
285 CxList *examineelem = NULL;
286 int examineclause = 0;
287
288 while(1) {
289 int cmd = dav_debug_ql_command();
290 switch (cmd) {
291 case DQLD_CMD_Q: return;
292 case DQLD_CMD_PS: dav_debug_ql_stmt_print(stmt); break;
293 case DQLD_CMD_PE: dav_debug_ql_expr_print(examineexpr); break;
294 case DQLD_CMD_PT: dav_debug_ql_tree_print(examineexpr, 1); break;
295 case DQLD_CMD_PF: dav_debug_ql_fnames_print(stmt); break;
296 case DQLD_CMD_F:
297 examineclause = DQLD_CMD_F;
298 examineelem = stmt->fields;
299 if (stmt->fields && stmt->fields->size > 0) {
300 DavQLField* field = cxListAt(stmt->fields, 0);
301 examineexpr = field->expr;
302 dav_debug_ql_field_print(field);
303 } else {
304 examineexpr = NULL;
305 }
306 break;
307 case DQLD_CMD_W:
308 examineclause = 0; examineelem = NULL;
309 examineexpr = stmt->where;
310 dav_debug_ql_expr_print(examineexpr);
311 break;
312 case DQLD_CMD_O:
313 examineclause = DQLD_CMD_O;
314 examineelem = stmt->orderby;
315 examineexpr = stmt->orderby && stmt->orderby->size > 0 ?
316 ((DavQLOrderCriterion*)cxListAt(stmt->orderby, 0))->column : NULL;
317 dav_debug_ql_expr_print(examineexpr);
318 break;
319 case DQLD_CMD_N:
320 case DQLD_CMD_P:
321 printf("TODO: port code to ucx 3\n");
322 /*
323 if (examineelem) {
324 CxList *newelem = (cmd == DQLD_CMD_N ?
325 examineelem->next : examineelem->prev);
326 if (newelem) {
327 examineelem = newelem;
328 if (examineclause == DQLD_CMD_O) {
329 examineexpr = ((DavQLOrderCriterion*)
330 examineelem->data)->column;
331 dav_debug_ql_expr_print(examineexpr);
332 } else if (examineclause == DQLD_CMD_F) {
333 DavQLField* field = (DavQLField*)examineelem->data;
334 examineexpr = field->expr;
335 dav_debug_ql_field_print(field);
336 } else {
337 printf("Examining unknown clause type.");
338 }
339 } else {
340 printf("Reached end of list.\n");
341 }
342 } else {
343 printf("Currently not examining an expression list.\n");
344 }
345 */
346 break;
347 case DQLD_CMD_L:
348 if (dav_debug_ql_expr_selected(examineexpr)) {
349 if (examineexpr->left) {
350 examineexpr = examineexpr->left;
351 dav_debug_ql_expr_print(examineexpr);
352 } else {
353 printf("There is no left subtree.\n");
354 }
355 }
356 break;
357 case DQLD_CMD_R:
358 if (dav_debug_ql_expr_selected(examineexpr)) {
359 if (examineexpr->right) {
360 examineexpr = examineexpr->right;
361 dav_debug_ql_expr_print(examineexpr);
362 } else {
363 printf("There is no right subtree.\n");
364 }
365 }
366 break;
367 case DQLD_CMD_H:
368 printf(
369 "\nCommands:\n"
370 "ps: print statement information\n"
371 "o: examine order by clause\n"
372 "f: examine field list\n"
373 "pf: print field names\n"
374 "w: examine where clause\n"
375 "n: examine next expression "
376 "(in order by clause or field list)\n"
377 "p: examine previous expression "
378 "(in order by clause or field list)\n"
379 "q: quit\n\n"
380 "\nExpression examination:\n"
381 "pe: print expression information\n"
382 "pt: print full syntax tree of current (sub-)expression\n"
383 "l: enter left subtree\n"
384 "r: enter right subtree\n");
385 break;
386 default: printf("unknown command\n");
387 }
388 }
389 }
390
391 // ------------------------------------------------------------------------
392 // P A R S E R
393 // ------------------------------------------------------------------------
394
395 #define _error_context "(%.*s[->]%.*s%.*s)"
396 #define _error_invalid "invalid statement"
397 #define _error_out_of_memory "out of memory"
398 #define _error_unexpected_token "unexpected token " _error_context
399 #define _error_invalid_token "invalid token " _error_context
400 #define _error_missing_path "expected path " _error_context
401 #define _error_missing_from "expecting FROM keyword " _error_context
402 #define _error_missing_at "expecting AT keyword " _error_context
403 #define _error_missing_by "expecting BY keyword " _error_context
404 #define _error_missing_as "expecting alias ('as <identifier>') " _error_context
405 #define _error_missing_identifier "expecting identifier " _error_context
406 #define _error_missing_par "missing closed parenthesis " _error_context
407 #define _error_missing_assign "expecting assignment ('=') " _error_context
408 #define _error_missing_where "SET statements must have a WHERE clause or " \
409 "explicitly use ANYWHERE " _error_context
410 #define _error_invalid_depth "invalid depth " _error_context
411 #define _error_missing_expr "missing expression " _error_context
412 #define _error_invalid_expr "invalid expression " _error_context
413 #define _error_invalid_unary_op "invalid unary operator " _error_context
414 #define _error_invalid_logical_op "invalid logical operator " _error_context
415 #define _error_invalid_fmtspec "invalid format specifier " _error_context
416 #define _error_invalid_string "string expected " _error_context
417 #define _error_invalid_order_criterion "invalid order criterion " _error_context
418
419 #define token_sstr(token) ((token)->value)
420
421 static void dav_error_in_context(int errorcode, const char *errormsg,
422 DavQLStatement *stmt, DavQLToken *token) {
423
424 // we try to achieve two things: get as many information as possible
425 // and recover the concrete source string (and not the token strings)
426 cxstring emptystring = CX_STR("");
427 cxstring prev = token->prev ? (token->prev->prev ?
428 token_sstr(token->prev->prev) : token_sstr(token->prev))
429 : emptystring;
430 cxstring tokenstr = token_sstr(token);
431 cxstring next = token->next ? (token->next->next ?
432 token_sstr(token->next->next) : token_sstr(token->next))
433 : emptystring;
434
435 int lp = prev.length == 0 ? 0 : tokenstr.ptr-prev.ptr;
436 const char *pn = tokenstr.ptr + tokenstr.length;
437 int ln = next.ptr+next.length - pn;
438
439 stmt->errorcode = errorcode;
440 stmt->errormessage = cx_asprintf(errormsg,
441 lp, prev.ptr,
442 sfmtarg(tokenstr),
443 ln, pn).ptr;
444 }
445
446 #define dqlsec_alloc_failed(ptr, stmt) \
447 if (!(ptr)) do { \
448 (stmt)->errorcode = DAVQL_ERROR_OUT_OF_MEMORY; \
449 return 0; \
450 } while(0)
451 #define dqlsec_malloc(stmt, ptr, type) \
452 dqlsec_alloc_failed(ptr = malloc(sizeof(type)), stmt)
453 #define dqlsec_mallocz(stmt, ptr, type) \
454 dqlsec_alloc_failed(ptr = calloc(1, sizeof(type)), stmt)
455
456
457 // special symbols are single tokens - the % sign MUST NOT be a special symbol
458 static const char *special_token_symbols = ",()+-*/&|^~=!<>";
459
460 static _Bool iskeyword(DavQLToken *token) {
461 cxstring keywords[] ={CX_STR("select"), CX_STR("set"), CX_STR("from"), CX_STR("at"), CX_STR("as"),
462 CX_STR("where"), CX_STR("anywhere"), CX_STR("like"), CX_STR("unlike"), CX_STR("and"),
463 CX_STR("or"), CX_STR("not"), CX_STR("xor"), CX_STR("with"), CX_STR("infinity"),
464 CX_STR("order"), CX_STR("by"), CX_STR("asc"), CX_STR("desc")
465 };
466 for (int i = 0 ; i < sizeof(keywords)/sizeof(cxstring) ; i++) {
467 if (!cx_strcasecmp(token->value, keywords[i])) {
468 return 1;
469 }
470 }
471 return 0;
472 }
473
474 static _Bool islongoperator(DavQLToken *token) {
475 cxstring operators[] = {CX_STR("and"), CX_STR("or"), CX_STR("not"), CX_STR("xor"),
476 CX_STR("like"), CX_STR("unlike")
477 };
478 for (int i = 0 ; i < sizeof(operators)/sizeof(cxstring) ; i++) {
479 if (!cx_strcasecmp(token->value, operators[i])) {
480 return 1;
481 }
482 }
483 return 0;
484 }
485
486 static int dav_stmt_add_field(DavQLStatement *stmt, DavQLField *field) {
487 if(!stmt->fields) {
488 stmt->fields = cxLinkedListCreateSimple(CX_STORE_POINTERS);
489 if(!stmt->fields) {
490 stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY;
491 return 1;
492 }
493 }
494
495 if(cxListAdd(stmt->fields, field)) {
496 stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY;
497 return 1;
498 }
499
500 return 0;
501 }
502
503
504 static void tokenlist_free(DavQLToken *tokenlist) {
505 DavQLToken *token = tokenlist;
506 while(token) {
507 DavQLToken *next = token->next;
508 free(token);
509 token = next;
510 }
511 }
512
513 static int dav_parse_add_token(DavQLToken **begin, DavQLToken **end, DavQLToken *token) {
514
515 // determine token class (order of if-statements is very important!)
516 char firstchar = token->value.ptr[0];
517
518 if (isdigit(firstchar)) {
519 token->tokenclass = DAVQL_TOKEN_NUMBER;
520 // check, if all characters are digits
521 for (size_t i = 1 ; i < token->value.length ; i++) {
522 if (!isdigit(token->value.ptr[i])) {
523 token->tokenclass = DAVQL_TOKEN_INVALID;
524 break;
525 }
526 }
527 } else if (firstchar == '%') {
528 token->tokenclass = DAVQL_TOKEN_FMTSPEC;
529 } else if (token->value.length == 1) {
530 switch (firstchar) {
531 case '(': token->tokenclass = DAVQL_TOKEN_OPENP; break;
532 case ')': token->tokenclass = DAVQL_TOKEN_CLOSEP; break;
533 case ',': token->tokenclass = DAVQL_TOKEN_COMMA; break;
534 default:
535 token->tokenclass = strchr(special_token_symbols, firstchar) ?
536 DAVQL_TOKEN_OPERATOR : DAVQL_TOKEN_IDENTIFIER;
537 }
538 } else if (islongoperator(token)) {
539 token->tokenclass = DAVQL_TOKEN_OPERATOR;
540 } else if (firstchar == '\'') {
541 token->tokenclass = DAVQL_TOKEN_STRING;
542 } else if (firstchar == '`') {
543 token->tokenclass = DAVQL_TOKEN_IDENTIFIER;
544 } else if (iskeyword(token)) {
545 token->tokenclass = DAVQL_TOKEN_KEYWORD;
546 } else {
547 token->tokenclass = DAVQL_TOKEN_IDENTIFIER;
548 // TODO: check for illegal characters
549 }
550
551 // remove quotes (extreme cool feature)
552 if (token->tokenclass == DAVQL_TOKEN_STRING ||
553 (token->tokenclass == DAVQL_TOKEN_IDENTIFIER && firstchar == '`')) {
554
555 char lastchar = token->value.ptr[token->value.length-1];
556 if (firstchar == lastchar) {
557 token->value.ptr++;
558 token->value.length -= 2;
559 } else {
560 token->tokenclass = DAVQL_TOKEN_INVALID;
561 }
562 }
563
564 cx_linked_list_add((void**)begin, (void**)end, offsetof(DavQLToken, prev), offsetof(DavQLToken, next), token);
565 return 0;
566 }
567
568
569
570 static DavQLToken* dav_parse_tokenize(cxstring src) {
571 #define alloc_token() do {token = calloc(1, sizeof(DavQLToken));\
572 if(!token) {tokenlist_free(tokens_begin); return NULL;}} while(0)
573 #define add_token() if(dav_parse_add_token(&tokens_begin, &tokens_end, token)) return NULL;
574
575 DavQLToken *tokens_begin = NULL;
576 DavQLToken *tokens_end = NULL;
577
578 DavQLToken *token = NULL;
579
580 char insequence = '\0';
581 for (size_t i = 0 ; i < src.length ; i++) {
582 // quoted strings / identifiers are a single token
583 if (src.ptr[i] == '\'' || src.ptr[i] == '`') {
584 if (src.ptr[i] == insequence) {
585 // lookahead for escaped string quotes
586 if (src.ptr[i] == '\'' && i+2 < src.length &&
587 src.ptr[i+1] == src.ptr[i] && src.ptr[i+2] == src.ptr[i]) {
588 token->value.length += 3;
589 i += 2;
590 } else {
591 // add quoted token to list
592 token->value.length++;
593 add_token();
594 token = NULL;
595 insequence = '\0';
596 }
597 } else if (insequence == '\0') {
598 insequence = src.ptr[i];
599 // always create new token for quoted strings
600 if (token) {
601 add_token();
602 }
603 alloc_token();
604 token->value.ptr = src.ptr + i;
605 token->value.length = 1;
606 } else {
607 // add other kind of quotes to token
608 token->value.length++;
609 }
610 } else if (insequence) {
611 token->value.length++;
612 } else if (isspace(src.ptr[i])) {
613 // add token before spaces to list (if any)
614 if (token) {
615 add_token();
616 token = NULL;
617 }
618 } else if (strchr(special_token_symbols, src.ptr[i])) {
619 // add token before special symbol to list (if any)
620 if (token) {
621 add_token();
622 token = NULL;
623 }
624 // add special symbol as single token to list
625 alloc_token();
626 token->value.ptr = src.ptr + i;
627 token->value.length = 1;
628 add_token();
629 // set tokenizer ready to read more tokens
630 token = NULL;
631 } else {
632 // if this is a new token, create memory for it
633 if (!token) {
634 alloc_token();
635 token->value.ptr = src.ptr + i;
636 token->value.length = 0;
637 }
638 // extend token length when reading more bytes
639 token->value.length++;
640 }
641 }
642
643 if (token) {
644 add_token();
645 }
646
647 alloc_token();
648 token->tokenclass = DAVQL_TOKEN_END;
649 token->value = CX_STR("");
650
651 cx_linked_list_add((void**)&tokens_begin, (void**)&tokens_end, offsetof(DavQLToken, prev), offsetof(DavQLToken, next), token);
652 return tokens_begin;
653 #undef alloc_token
654 #undef add_token
655 }
656
657 static void dav_free_expression(DavQLExpression *expr) {
658 if (expr) {
659 if (expr->left) {
660 dav_free_expression(expr->left);
661 }
662 if (expr->right) {
663 dav_free_expression(expr->right);
664 }
665 free(expr);
666 }
667 }
668
669 static void dav_free_field(DavQLField *field) {
670 dav_free_expression(field->expr);
671 free(field);
672 }
673
674 static void dav_free_order_criterion(DavQLOrderCriterion *crit) {
675 if (crit->column) { // do it null-safe though column is expected to be set
676 dav_free_expression(crit->column);
677 }
678 }
679
680 #define token_is(token, expectedclass) (token && \
681 (token->tokenclass == expectedclass))
682
683 #define tokenvalue_is(token, expectedvalue) (token && \
684 !cx_strcasecmp(token->value, cx_str(expectedvalue)))
685
686 typedef int(*exprparser_f)(DavQLStatement*,DavQLToken*,DavQLExpression*);
687
688 static int dav_parse_binary_expr(DavQLStatement* stmt, DavQLToken* token,
689 DavQLExpression* expr, exprparser_f parseL, char* opc, int* opv,
690 exprparser_f parseR) {
691
692 if (!token) {
693 return 0;
694 }
695
696 int total_consumed = 0, consumed;
697
698 // save temporarily on stack (copy to heap later on)
699 DavQLExpression left, right;
700
701 // RULE: LEFT, [Operator, RIGHT]
702 memset(&left, 0, sizeof(DavQLExpression));
703 consumed = parseL(stmt, token, &left);
704 if (!consumed || stmt->errorcode) {
705 return 0;
706 }
707 total_consumed += consumed;
708 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
709
710 char *op;
711 if (token_is(token, DAVQL_TOKEN_OPERATOR) &&
712 (op = strchr(opc, token_sstr(token).ptr[0]))) {
713 expr->op = opv[op-opc];
714 expr->type = DAVQL_BINARY;
715 total_consumed++;
716 token = token->next;
717 memset(&right, 0, sizeof(DavQLExpression));
718 consumed = parseR(stmt, token, &right);
719 if (stmt->errorcode) {
720 return 0;
721 }
722 if (!consumed) {
723 dav_error_in_context(DAVQL_ERROR_MISSING_EXPR,
724 _error_missing_expr, stmt, token);
725 return 0;
726 }
727 total_consumed += consumed;
728 }
729
730 if (expr->op == DAVQL_NOOP) {
731 memcpy(expr, &left, sizeof(DavQLExpression));
732 } else {
733 dqlsec_malloc(stmt, expr->left, DavQLExpression);
734 memcpy(expr->left, &left, sizeof(DavQLExpression));
735 dqlsec_malloc(stmt, expr->right, DavQLExpression);
736 memcpy(expr->right, &right, sizeof(DavQLExpression));
737
738 expr->srctext.ptr = expr->left->srctext.ptr;
739 expr->srctext.length =
740 expr->right->srctext.ptr -
741 expr->left->srctext.ptr + expr->right->srctext.length;
742 }
743
744 return total_consumed;
745 }
746
747 static void fmt_args_add(DavQLStatement *stmt, void *data) {
748 if(!stmt->args) {
749 stmt->args = cxLinkedListCreateSimple(CX_STORE_POINTERS);
750 }
751 cxListAdd(stmt->args, data);
752 }
753
754 static void dav_add_fmt_args(DavQLStatement *stmt, cxstring str) {
755 int placeholder = 0;
756 for (size_t i=0;i<str.length;i++) {
757 char c = str.ptr[i];
758 if (placeholder) {
759 if (c != '%') {
760 fmt_args_add(stmt, (void*)(intptr_t)c);
761 }
762 placeholder = 0;
763 } else if (c == '%') {
764 placeholder = 1;
765 }
766 }
767 }
768
769 static int dav_parse_literal(DavQLStatement* stmt, DavQLToken* token,
770 DavQLExpression* expr) {
771
772 expr->srctext = token_sstr(token);
773 if (token_is(token, DAVQL_TOKEN_NUMBER)) {
774 expr->type = DAVQL_NUMBER;
775 } else if (token_is(token, DAVQL_TOKEN_STRING)) {
776 expr->type = DAVQL_STRING;
777 // check for format specifiers and add args
778 dav_add_fmt_args(stmt, expr->srctext);
779 } else if (token_is(token, DAVQL_TOKEN_TIMESTAMP)) {
780 expr->type = DAVQL_TIMESTAMP;
781 } else if (token_is(token, DAVQL_TOKEN_FMTSPEC)
782 && expr->srctext.length == 2) {
783 switch (expr->srctext.ptr[1]) {
784 case 'd': expr->type = DAVQL_NUMBER; break;
785 case 's': expr->type = DAVQL_STRING; break;
786 case 't': expr->type = DAVQL_TIMESTAMP; break;
787 default:
788 dav_error_in_context(DAVQL_ERROR_INVALID_FMTSPEC,
789 _error_invalid_fmtspec, stmt, token);
790 return 0;
791 }
792 // add fmtspec type to query arg list
793 fmt_args_add(stmt, (void*)(intptr_t)expr->srctext.ptr[1]);
794 } else {
795 return 0;
796 }
797
798 return 1;
799 }
800
801 // forward declaration
802 static int dav_parse_expression(DavQLStatement* stmt, DavQLToken* token,
803 DavQLExpression* expr);
804
805 static int dav_parse_arglist(DavQLStatement* stmt, DavQLToken* token,
806 DavQLExpression* expr) {
807
808 expr->srctext.ptr = token_sstr(token).ptr;
809 expr->srctext.length = 0;
810 expr->left = expr->right = NULL; // in case we fail, we want them to be sane
811
812 int total_consumed = 0;
813
814 // RULE: Expression, {",", Expression};
815 DavQLExpression *arglist = expr;
816 DavQLExpression arg;
817 const char *lastchar = expr->srctext.ptr;
818 int consumed;
819 do {
820 memset(&arg, 0, sizeof(DavQLExpression));
821 consumed = dav_parse_expression(stmt, token, &arg);
822 if (consumed) {
823 lastchar = arg.srctext.ptr + arg.srctext.length;
824 total_consumed += consumed;
825 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
826 // look ahead for a comma
827 if (token_is(token, DAVQL_TOKEN_COMMA)) {
828 total_consumed++;
829 token = token->next;
830 /* we have more arguments, so put the current argument to the
831 * left subtree and create a new node to the right
832 */
833 dqlsec_malloc(stmt, arglist->left, DavQLExpression);
834 memcpy(arglist->left, &arg, sizeof(DavQLExpression));
835 arglist->srctext.ptr = arg.srctext.ptr;
836 arglist->op = DAVQL_ARGLIST;
837 arglist->type = DAVQL_FUNCCALL;
838 dqlsec_mallocz(stmt, arglist->right, DavQLExpression);
839 arglist = arglist->right;
840 } else {
841 // this was the last argument, so write it to the current node
842 memcpy(arglist, &arg, sizeof(DavQLExpression));
843 consumed = 0;
844 }
845 }
846 } while (consumed && !stmt->errorcode);
847
848 // recover source text
849 arglist = expr;
850 while (arglist && arglist->type == DAVQL_FUNCCALL) {
851 arglist->srctext.length = lastchar - arglist->srctext.ptr;
852 arglist = arglist->right;
853 }
854
855 return total_consumed;
856 }
857
858 static int dav_parse_funccall(DavQLStatement* stmt, DavQLToken* token,
859 DavQLExpression* expr) {
860
861 // RULE: Identifier, "(", ArgumentList, ")";
862 if (token_is(token, DAVQL_TOKEN_IDENTIFIER) &&
863 token_is(token->next, DAVQL_TOKEN_OPENP)) {
864
865 expr->type = DAVQL_FUNCCALL;
866 expr->op = DAVQL_CALL;
867
868 dqlsec_mallocz(stmt, expr->left, DavQLExpression);
869 expr->left->type = DAVQL_IDENTIFIER;
870 expr->left->srctext = token_sstr(token);
871 expr->right = NULL;
872
873 token = token->next->next;
874
875 DavQLExpression arg;
876 int argtokens = dav_parse_arglist(stmt, token, &arg);
877 if (stmt->errorcode) {
878 // if an error occurred while parsing the arglist, return now
879 return 2;
880 }
881 if (argtokens) {
882 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), argtokens);
883 dqlsec_malloc(stmt, expr->right, DavQLExpression);
884 memcpy(expr->right, &arg, sizeof(DavQLExpression));
885 } else {
886 // arg list may be empty
887 expr->right = NULL;
888 }
889
890 if (token_is(token, DAVQL_TOKEN_CLOSEP)) {
891 return 3 + argtokens;
892 } else {
893 dav_error_in_context(DAVQL_ERROR_MISSING_PAR, _error_missing_par,
894 stmt, token);
895 return 2; // it MUST be a function call, but it is invalid
896 }
897 } else {
898 return 0;
899 }
900 }
901
902 static int dav_parse_unary_expr(DavQLStatement* stmt, DavQLToken* token,
903 DavQLExpression* expr) {
904
905 DavQLToken *firsttoken = token; // save for srctext recovery
906
907 DavQLExpression* atom = expr;
908 int total_consumed = 0;
909
910 // optional unary operator
911 if (token_is(token, DAVQL_TOKEN_OPERATOR)) {
912 char *op = strchr("+-~", token_sstr(token).ptr[0]);
913 if (op) {
914 expr->type = DAVQL_UNARY;
915 switch (*op) {
916 case '+': expr->op = DAVQL_ADD; break;
917 case '-': expr->op = DAVQL_SUB; break;
918 case '~': expr->op = DAVQL_NEG; break;
919 }
920 dqlsec_mallocz(stmt, expr->left, DavQLExpression);
921 atom = expr->left;
922 total_consumed++;
923 token = token->next;
924 } else {
925 dav_error_in_context(DAVQL_ERROR_INVALID_UNARY_OP,
926 _error_invalid_unary_op, stmt, token);
927 return 0;
928 }
929 }
930
931 // RULE: (ParExpression | AtomicExpression)
932 if (token_is(token, DAVQL_TOKEN_OPENP)) {
933 token = token->next; total_consumed++;
934 // RULE: "(", Expression, ")"
935 int consumed = dav_parse_expression(stmt, token, atom);
936 if (stmt->errorcode) {
937 return 0;
938 }
939 if (!consumed) {
940 dav_error_in_context(DAVQL_ERROR_INVALID_EXPR,
941 _error_invalid_expr, stmt, token);
942 return 0;
943 }
944 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
945 total_consumed += consumed;
946 if (token_is(token, DAVQL_TOKEN_CLOSEP)) {
947 token = token->next; total_consumed++;
948 } else {
949 dav_error_in_context(DAVQL_ERROR_MISSING_PAR,
950 _error_missing_par, stmt, token);
951 return 0;
952 }
953 } else {
954 // RULE: FunctionCall
955 int consumed = dav_parse_funccall(stmt, token, atom);
956 if (consumed) {
957 total_consumed += consumed;
958 } else if (token_is(token, DAVQL_TOKEN_IDENTIFIER)) {
959 // RULE: Identifier
960 total_consumed++;
961 atom->type = DAVQL_IDENTIFIER;
962 atom->srctext = token_sstr(token);
963 } else {
964 // RULE: Literal
965 total_consumed += dav_parse_literal(stmt, token, atom);
966 }
967 }
968
969 // recover source text
970 expr->srctext.ptr = token_sstr(firsttoken).ptr;
971 if (total_consumed > 0) {
972 cxstring lasttoken =
973 token_sstr((DavQLToken*)cx_linked_list_at(token, 0, offsetof(DavQLToken, next), total_consumed-1));
974 expr->srctext.length =
975 lasttoken.ptr - expr->srctext.ptr + lasttoken.length;
976 } else {
977 // the expression should not be used anyway, but we want to be safe
978 expr->srctext.length = 0;
979 }
980
981
982 return total_consumed;
983 }
984
985 static int dav_parse_bitexpr(DavQLStatement* stmt, DavQLToken* token,
986 DavQLExpression* expr) {
987
988 return dav_parse_binary_expr(stmt, token, expr,
989 dav_parse_unary_expr,
990 "&|^", (int[]){DAVQL_AND, DAVQL_OR, DAVQL_XOR},
991 dav_parse_bitexpr);
992 }
993
994 static int dav_parse_multexpr(DavQLStatement* stmt, DavQLToken* token,
995 DavQLExpression* expr) {
996
997 return dav_parse_binary_expr(stmt, token, expr,
998 dav_parse_bitexpr,
999 "*/", (int[]){DAVQL_MUL, DAVQL_DIV},
1000 dav_parse_multexpr);
1001 }
1002
1003 static int dav_parse_expression(DavQLStatement* stmt, DavQLToken* token,
1004 DavQLExpression* expr) {
1005
1006 return dav_parse_binary_expr(stmt, token, expr,
1007 dav_parse_multexpr,
1008 "+-", (int[]){DAVQL_ADD, DAVQL_SUB},
1009 dav_parse_expression);
1010 }
1011
1012 static int dav_parse_named_field(DavQLStatement *stmt, DavQLToken *token,
1013 DavQLField *field) {
1014 int total_consumed = 0, consumed;
1015
1016 // RULE: Expression, " as ", Identifier;
1017 DavQLExpression *expr;
1018 dqlsec_mallocz(stmt, expr, DavQLExpression);
1019 consumed = dav_parse_expression(stmt, token, expr);
1020 if (stmt->errorcode) {
1021 dav_free_expression(expr);
1022 return 0;
1023 }
1024 if (expr->type == DAVQL_UNDEFINED_TYPE) {
1025 dav_free_expression(expr);
1026 dav_error_in_context(DAVQL_ERROR_INVALID_EXPR,
1027 _error_invalid_expr, stmt, token);
1028 return 0;
1029 }
1030
1031 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1032 total_consumed += consumed;
1033
1034 if (token_is(token, DAVQL_TOKEN_KEYWORD) && tokenvalue_is(token, "as")) {
1035 token = token->next; total_consumed++;
1036 } else {
1037 dav_free_expression(expr);
1038 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1039 _error_missing_as, stmt, token);
1040 return 0;
1041 }
1042
1043 if (token_is(token, DAVQL_TOKEN_IDENTIFIER)) {
1044 field->name = token_sstr(token);
1045 field->expr = expr;
1046 return total_consumed + 1;
1047 } else {
1048 dav_free_expression(expr);
1049 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1050 _error_missing_identifier, stmt, token);
1051 return 0;
1052 }
1053 }
1054
1055 static int dav_parse_fieldlist(DavQLStatement *stmt, DavQLToken *token) {
1056
1057 // RULE: "-"
1058 if (token_is(token, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(token, "-")) {
1059 DavQLField *field;
1060 dqlsec_malloc(stmt, field, DavQLField);
1061 if(dav_stmt_add_field(stmt, field)) {
1062 free(field);
1063 return 0;
1064 }
1065 dqlsec_mallocz(stmt, field->expr, DavQLExpression);
1066 field->expr->type = DAVQL_IDENTIFIER;
1067 field->expr->srctext = field->name = token_sstr(token);
1068 return 1;
1069 }
1070
1071 // RULE: "*", {",", NamedExpression}
1072 if (token_is(token, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(token, "*")) {
1073 DavQLField *field;
1074 dqlsec_malloc(stmt, field, DavQLField);
1075 if(dav_stmt_add_field(stmt, field)) {
1076 free(field);
1077 return 0;
1078 }
1079 dqlsec_mallocz(stmt, field->expr, DavQLExpression);
1080 field->expr->type = DAVQL_IDENTIFIER;
1081 field->expr->srctext = field->name = token_sstr(token);
1082
1083 int total_consumed = 0;
1084 int consumed = 1;
1085
1086 do {
1087 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1088 total_consumed += consumed;
1089
1090 if (token_is(token, DAVQL_TOKEN_COMMA)) {
1091 total_consumed++; token = token->next;
1092 DavQLField localfield;
1093 consumed = dav_parse_named_field(stmt, token, &localfield);
1094 if (!stmt->errorcode && consumed) {
1095 DavQLField *field;
1096 dqlsec_malloc(stmt, field, DavQLField);
1097 memcpy(field, &localfield, sizeof(DavQLField));
1098 if(dav_stmt_add_field(stmt, field)) {
1099 free(field);
1100 return 0;
1101 }
1102 }
1103 } else {
1104 consumed = 0;
1105 }
1106 } while (consumed > 0);
1107
1108 return total_consumed;
1109 }
1110
1111 // RULE: FieldExpression, {",", FieldExpression}
1112 {
1113 int total_consumed = 0, consumed;
1114 do {
1115 // RULE: NamedField | Identifier
1116 DavQLField localfield;
1117 consumed = dav_parse_named_field(stmt, token, &localfield);
1118 if (consumed) {
1119 DavQLField *field;
1120 dqlsec_malloc(stmt, field, DavQLField);
1121 memcpy(field, &localfield, sizeof(DavQLField));
1122 if(dav_stmt_add_field(stmt, field)) {
1123 free(field);
1124 return 0;
1125 }
1126 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1127 total_consumed += consumed;
1128 } else if (token_is(token, DAVQL_TOKEN_IDENTIFIER)
1129 // look ahead, if the field is JUST the identifier
1130 && (token_is(token->next, DAVQL_TOKEN_COMMA) ||
1131 tokenvalue_is(token->next, "from"))) {
1132
1133 DavQLField *field;
1134 dqlsec_malloc(stmt, field, DavQLField);
1135 dqlsec_mallocz(stmt, field->expr, DavQLExpression);
1136 field->expr->type = DAVQL_IDENTIFIER;
1137 field->expr->srctext = field->name = token_sstr(token);
1138 if(dav_stmt_add_field(stmt, field)) {
1139 free(field);
1140 return 0;
1141 }
1142
1143 consumed = 1;
1144 total_consumed++;
1145 token = token->next;
1146
1147 // we found a valid solution, so erase any errors
1148 stmt->errorcode = 0;
1149 if (stmt->errormessage) {
1150 free(stmt->errormessage);
1151 stmt->errormessage = NULL;
1152 }
1153 } else {
1154 // dav_parse_named_field has already thrown a good error
1155 consumed = 0;
1156 }
1157
1158 // field has been parsed, now try to get a comma
1159 if (consumed) {
1160 consumed = token_is(token, DAVQL_TOKEN_COMMA) ? 1 : 0;
1161 if (consumed) {
1162 token = token->next;
1163 total_consumed++;
1164 }
1165 }
1166 } while (consumed);
1167
1168 return total_consumed;
1169 }
1170 }
1171
1172 // forward declaration
1173 static int dav_parse_logical_expr(DavQLStatement *stmt, DavQLToken *token,
1174 DavQLExpression *expr);
1175
1176 static int dav_parse_bool_prim(DavQLStatement *stmt, DavQLToken *token,
1177 DavQLExpression *expr) {
1178
1179 expr->type = DAVQL_LOGICAL;
1180 expr->srctext = token_sstr(token);
1181
1182 int total_consumed = 0;
1183
1184 DavQLExpression bexpr;
1185 memset(&bexpr, 0, sizeof(DavQLExpression));
1186 total_consumed = dav_parse_expression(stmt, token, &bexpr);
1187 if (!total_consumed || stmt->errorcode) {
1188 return 0;
1189 }
1190 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), total_consumed);
1191
1192 DavQLToken* optok = token;
1193 // RULE: Expression, (" like " | " unlike "), String
1194 if (token_is(optok, DAVQL_TOKEN_OPERATOR) && (tokenvalue_is(optok,
1195 "like") || tokenvalue_is(optok, "unlike"))) {
1196
1197 total_consumed++;
1198 token = token->next;
1199 if (token_is(token, DAVQL_TOKEN_STRING)) {
1200 expr->op = tokenvalue_is(optok, "like") ?
1201 DAVQL_LIKE : DAVQL_UNLIKE;
1202 dqlsec_malloc(stmt, expr->left, DavQLExpression);
1203 memcpy(expr->left, &bexpr, sizeof(DavQLExpression));
1204 dqlsec_mallocz(stmt, expr->right, DavQLExpression);
1205 expr->right->type = DAVQL_STRING;
1206 expr->right->srctext = token_sstr(token);
1207 expr->srctext.length = expr->right->srctext.ptr -
1208 expr->srctext.ptr + expr->right->srctext.length;
1209
1210 // fmt args
1211 dav_add_fmt_args(stmt, expr->right->srctext);
1212
1213 return total_consumed + 1;
1214 } else {
1215 dav_error_in_context(DAVQL_ERROR_INVALID_STRING,
1216 _error_invalid_string, stmt, token);
1217 return 0;
1218 }
1219 }
1220 // RULE: Expression, Comparison, Expression
1221 else if (token_is(optok, DAVQL_TOKEN_OPERATOR) && (
1222 tokenvalue_is(optok, "=") || tokenvalue_is(optok, "!") ||
1223 tokenvalue_is(optok, "<") || tokenvalue_is(optok, ">"))) {
1224
1225 total_consumed++;
1226 token = token->next;
1227
1228 if (tokenvalue_is(optok, "=")) {
1229 expr->op = DAVQL_EQ;
1230 } else {
1231 if (tokenvalue_is(token, "=")) {
1232 if (tokenvalue_is(optok, "!")) {
1233 expr->op = DAVQL_NEQ;
1234 } else if (tokenvalue_is(optok, "<")) {
1235 expr->op = DAVQL_LE;
1236 } else if (tokenvalue_is(optok, ">")) {
1237 expr->op = DAVQL_GE;
1238 }
1239 total_consumed++;
1240 token = token->next;
1241 } else {
1242 if (tokenvalue_is(optok, "<")) {
1243 expr->op = DAVQL_LT;
1244 } else if (tokenvalue_is(optok, ">")) {
1245 expr->op = DAVQL_GT;
1246 }
1247 }
1248 }
1249
1250 DavQLExpression rexpr;
1251 memset(&rexpr, 0, sizeof(DavQLExpression));
1252 int consumed = dav_parse_expression(stmt, token, &rexpr);
1253 if (stmt->errorcode) {
1254 return 0;
1255 }
1256 if (!consumed) {
1257 dav_error_in_context(
1258 DAVQL_ERROR_MISSING_EXPR, _error_missing_expr,
1259 stmt, token);
1260 return 0;
1261 }
1262
1263 total_consumed += consumed;
1264 dqlsec_malloc(stmt, expr->left, DavQLExpression);
1265 memcpy(expr->left, &bexpr, sizeof(DavQLExpression));
1266 dqlsec_malloc(stmt, expr->right, DavQLExpression);
1267 memcpy(expr->right, &rexpr, sizeof(DavQLExpression));
1268
1269 expr->srctext.length = expr->right->srctext.ptr -
1270 expr->srctext.ptr + expr->right->srctext.length;
1271
1272 return total_consumed;
1273 }
1274 // RULE: FunctionCall | Identifier;
1275 else if (bexpr.type == DAVQL_FUNCCALL || bexpr.type == DAVQL_IDENTIFIER) {
1276 memcpy(expr, &bexpr, sizeof(DavQLExpression));
1277
1278 return total_consumed;
1279 } else {
1280 return 0;
1281 }
1282 }
1283
1284 static int dav_parse_bool_expr(DavQLStatement *stmt, DavQLToken *token,
1285 DavQLExpression *expr) {
1286
1287 // RULE: "not ", LogicalExpression
1288 if (token_is(token, DAVQL_TOKEN_OPERATOR) && tokenvalue_is(token, "not")) {
1289 expr->type = DAVQL_LOGICAL;
1290 expr->op = DAVQL_NOT;
1291 dqlsec_mallocz(stmt, expr->left, DavQLExpression);
1292 expr->srctext = token_sstr(token);
1293
1294 token = token->next;
1295 int consumed = dav_parse_bool_expr(stmt, token, expr->left);
1296 if (stmt->errorcode) {
1297 return 0;
1298 }
1299 if (consumed) {
1300 cxstring lasttok = token_sstr((DavQLToken*)cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed-1));
1301 expr->srctext.length =
1302 lasttok.ptr - expr->srctext.ptr + lasttok.length;
1303 return consumed + 1;
1304 } else {
1305 dav_error_in_context(DAVQL_ERROR_MISSING_EXPR,
1306 _error_missing_expr, stmt, token);
1307 return 0;
1308 }
1309 }
1310 // RULE: "(", LogicalExpression, ")"
1311 else if (token_is(token, DAVQL_TOKEN_OPENP)) {
1312 int consumed = dav_parse_logical_expr(stmt, token->next, expr);
1313 if (consumed) {
1314 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1315
1316 if (token_is(token, DAVQL_TOKEN_CLOSEP)) {
1317 token = token->next;
1318 return consumed + 2;
1319 } else {
1320 dav_error_in_context(DAVQL_ERROR_MISSING_PAR, _error_missing_par,
1321 stmt, token);
1322 return 0;
1323 }
1324 } else {
1325 // don't handle errors here, we can also try a boolean primary
1326 stmt->errorcode = 0;
1327 if (stmt->errormessage) {
1328 free(stmt->errormessage);
1329 }
1330 }
1331 }
1332
1333 // RULE: BooleanPrimary
1334 return dav_parse_bool_prim(stmt, token, expr);
1335 }
1336
1337 static int dav_parse_logical_expr(DavQLStatement *stmt, DavQLToken *token,
1338 DavQLExpression *expr) {
1339
1340 DavQLToken *firsttoken = token;
1341 int total_consumed = 0;
1342
1343 // RULE: BooleanLiteral, [LogicalOperator, LogicalExpression];
1344 DavQLExpression left, right;
1345 memset(&left, 0, sizeof(DavQLExpression));
1346 int consumed = dav_parse_bool_expr(stmt, token, &left);
1347 if (stmt->errorcode) {
1348 return 0;
1349 }
1350 if (!consumed) {
1351 dav_error_in_context(DAVQL_ERROR_MISSING_EXPR,
1352 _error_missing_expr, stmt, token);
1353 return 0;
1354 }
1355 total_consumed += consumed;
1356 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1357
1358 if (token_is(token, DAVQL_TOKEN_OPERATOR)) {
1359 expr->type = DAVQL_LOGICAL;
1360
1361 davqloperator_t op = DAVQL_NOOP;
1362 if (tokenvalue_is(token, "and")) {
1363 op = DAVQL_LAND;
1364 } else if (tokenvalue_is(token, "or")) {
1365 op = DAVQL_LOR;
1366 } else if (tokenvalue_is(token, "xor")) {
1367 op = DAVQL_LXOR;
1368 }
1369
1370 if (op == DAVQL_NOOP) {
1371 dav_error_in_context(DAVQL_ERROR_INVALID_LOGICAL_OP,
1372 _error_invalid_logical_op, stmt, token);
1373 return 0;
1374 } else {
1375 expr->op = op;
1376 total_consumed++;
1377 token = token->next;
1378
1379 memset(&right, 0, sizeof(DavQLExpression));
1380 consumed = dav_parse_logical_expr(stmt, token, &right);
1381 if (stmt->errorcode) {
1382 return 0;
1383 }
1384 if (!consumed) {
1385 dav_error_in_context(DAVQL_ERROR_MISSING_EXPR,
1386 _error_missing_expr, stmt, token);
1387 return 0;
1388 }
1389 total_consumed += consumed;
1390 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1391
1392 dqlsec_malloc(stmt, expr->left, DavQLExpression);
1393 memcpy(expr->left, &left, sizeof(DavQLExpression));
1394 dqlsec_malloc(stmt, expr->right, DavQLExpression);
1395 memcpy(expr->right, &right, sizeof(DavQLExpression));
1396 }
1397 } else {
1398 memcpy(expr, &left, sizeof(DavQLExpression));
1399 }
1400
1401 // set type and recover source text
1402 if (total_consumed > 0) {
1403 expr->srctext.ptr = token_sstr(firsttoken).ptr;
1404 cxstring lasttok = token_sstr((DavQLToken*)cx_linked_list_at(firsttoken, 0, offsetof(DavQLToken, next), total_consumed-1));
1405 expr->srctext.length = lasttok.ptr-expr->srctext.ptr+lasttok.length;
1406 }
1407
1408 return total_consumed;
1409 }
1410
1411 static int dav_parse_where_clause(DavQLStatement *stmt, DavQLToken *token) {
1412 dqlsec_mallocz(stmt, stmt->where, DavQLExpression);
1413
1414 return dav_parse_logical_expr(stmt, token, stmt->where);
1415 }
1416
1417 static int dav_parse_with_clause(DavQLStatement *stmt, DavQLToken *token) {
1418
1419 int total_consumed = 0;
1420
1421 // RULE: "depth", "=", (Number | "infinity")
1422 if (tokenvalue_is(token, "depth")) {
1423 token = token->next; total_consumed++;
1424 if (tokenvalue_is(token, "=")) {
1425 token = token->next; total_consumed++;
1426 if (tokenvalue_is(token, "infinity")) {
1427 stmt->depth = DAV_DEPTH_INFINITY;
1428 token = token->next; total_consumed++;
1429 } else {
1430 DavQLExpression *depthexpr;
1431 dqlsec_mallocz(stmt, depthexpr, DavQLExpression);
1432
1433 int consumed = dav_parse_expression(stmt, token, depthexpr);
1434
1435 if (consumed) {
1436 if (depthexpr->type == DAVQL_NUMBER) {
1437 if (depthexpr->srctext.ptr[0] == '%') {
1438 stmt->depth = DAV_DEPTH_PLACEHOLDER;
1439 } else {
1440 cxstring depthstr = depthexpr->srctext;
1441 char *conv = malloc(depthstr.length+1);
1442 if (!conv) {
1443 dav_free_expression(depthexpr);
1444 stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY;
1445 return 0;
1446 }
1447 char *chk;
1448 memcpy(conv, depthstr.ptr, depthstr.length);
1449 conv[depthstr.length] = '\0';
1450 stmt->depth = strtol(conv, &chk, 10);
1451 if (*chk || stmt->depth < -1) {
1452 dav_error_in_context(DAVQL_ERROR_INVALID_DEPTH,
1453 _error_invalid_depth, stmt, token);
1454 }
1455 free(conv);
1456 }
1457 total_consumed += consumed;
1458 } else {
1459 dav_error_in_context(DAVQL_ERROR_INVALID_DEPTH,
1460 _error_invalid_depth, stmt, token);
1461 }
1462 }
1463
1464 dav_free_expression(depthexpr);
1465 }
1466 }
1467 }
1468
1469 return total_consumed;
1470 }
1471
1472 static int dav_parse_order_crit(DavQLStatement *stmt, DavQLToken *token,
1473 DavQLOrderCriterion *crit) {
1474
1475 // RULE: (Identifier | Number), [" asc"|" desc"];
1476 DavQLExpression expr;
1477 memset(&expr, 0, sizeof(DavQLExpression));
1478 int consumed = dav_parse_expression(stmt, token, &expr);
1479 if (stmt->errorcode || !consumed) {
1480 return 0;
1481 }
1482
1483 if (expr.type != DAVQL_IDENTIFIER && expr.type != DAVQL_NUMBER) {
1484 dav_error_in_context(DAVQL_ERROR_INVALID_ORDER_CRITERION,
1485 _error_invalid_order_criterion, stmt, token);
1486 return 0;
1487 }
1488
1489 dqlsec_malloc(stmt, crit->column, DavQLExpression);
1490 memcpy(crit->column, &expr, sizeof(DavQLExpression));
1491
1492 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1493 if (token_is(token, DAVQL_TOKEN_KEYWORD) && (
1494 tokenvalue_is(token, "asc") || tokenvalue_is(token, "desc"))) {
1495
1496 crit->descending = tokenvalue_is(token, "desc");
1497
1498 return consumed+1;
1499 } else {
1500 crit->descending = 0;
1501 return consumed;
1502 }
1503 }
1504
1505 static int dav_parse_orderby_clause(DavQLStatement *stmt, DavQLToken *token) {
1506
1507 int total_consumed = 0, consumed;
1508
1509 DavQLOrderCriterion crit;
1510
1511 if(!stmt->orderby) {
1512 stmt->orderby = cxLinkedListCreateSimple(sizeof(DavQLOrderCriterion));
1513 if(!stmt->orderby) {
1514 return 0;
1515 }
1516 }
1517
1518 // RULE: OrderByCriterion, {",", OrderByCriterion};
1519 do {
1520 consumed = dav_parse_order_crit(stmt, token, &crit);
1521 if (stmt->errorcode) {
1522 return 0;
1523 }
1524 if (!consumed) {
1525 dav_error_in_context(DAVQL_ERROR_MISSING_EXPR, _error_missing_expr,
1526 stmt, token);
1527 return 0;
1528 }
1529 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1530 total_consumed += consumed;
1531
1532 if(cxListAdd(stmt->orderby, &crit)) {
1533 stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY;
1534 return 0;
1535 }
1536
1537 if (token_is(token, DAVQL_TOKEN_COMMA)) {
1538 total_consumed++;
1539 token = token->next;
1540 } else {
1541 consumed = 0;
1542 }
1543 } while (consumed);
1544
1545 return total_consumed;
1546 }
1547
1548
1549 static int dav_parse_assignments(DavQLStatement *stmt, DavQLToken *token) {
1550
1551 // RULE: Assignment, {",", Assignment}
1552 int total_consumed = 0, consumed;
1553 do {
1554 // RULE: Identifier, "=", Expression
1555 if (token_is(token, DAVQL_TOKEN_IDENTIFIER)) {
1556
1557 // Identifier
1558 DavQLField *field;
1559 dqlsec_malloc(stmt, field, DavQLField);
1560 field->name = token_sstr(token);
1561 total_consumed++;
1562 token = token->next;
1563
1564 // "="
1565 if (!token_is(token, DAVQL_TOKEN_OPERATOR)
1566 || !tokenvalue_is(token, "=")) {
1567 dav_free_field(field);
1568
1569 dav_error_in_context(DAVQL_ERROR_MISSING_ASSIGN,
1570 _error_missing_assign, stmt, token);
1571 return total_consumed;
1572 }
1573 total_consumed++;
1574 token = token->next;
1575
1576 // Expression
1577 dqlsec_mallocz(stmt, field->expr, DavQLExpression);
1578 consumed = dav_parse_expression(stmt, token, field->expr);
1579 if (stmt->errorcode) {
1580 dav_free_field(field);
1581 return total_consumed;
1582 }
1583 token = cx_linked_list_at(token, 0, offsetof(DavQLToken, next), consumed);
1584 total_consumed += consumed;
1585
1586 // Add assignment to list and check if there's another one
1587 if(dav_stmt_add_field(stmt, field)) {
1588 free(field);
1589 return 0;
1590 }
1591 consumed = token_is(token, DAVQL_TOKEN_COMMA) ? 1 : 0;
1592 if (consumed) {
1593 token = token->next;
1594 total_consumed++;
1595 }
1596 } else {
1597 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1598 _error_missing_identifier, stmt, token);
1599 return total_consumed;
1600 }
1601 } while (consumed);
1602
1603 return total_consumed;
1604 }
1605
1606 static int dav_parse_path(DavQLStatement *stmt, DavQLToken *tokens) {
1607 if (token_is(tokens, DAVQL_TOKEN_STRING)) {
1608 stmt->path = token_sstr(tokens);
1609 tokens = tokens->next;
1610 return 1;
1611 } else if (token_is(tokens, DAVQL_TOKEN_OPERATOR)
1612 && tokenvalue_is(tokens, "/")) {
1613 stmt->path = token_sstr(tokens);
1614 tokens = tokens->next;
1615 int consumed = 1;
1616 while (!token_is(tokens, DAVQL_TOKEN_KEYWORD) &&
1617 !token_is(tokens, DAVQL_TOKEN_END)) {
1618 cxstring toksstr = token_sstr(tokens);
1619 stmt->path.length = toksstr.ptr-stmt->path.ptr+toksstr.length;
1620 tokens = tokens->next;
1621 consumed++;
1622 }
1623 return consumed;
1624 } else if (token_is(tokens, DAVQL_TOKEN_FMTSPEC) &&
1625 tokenvalue_is(tokens, "%s")) {
1626 stmt->path = token_sstr(tokens);
1627 tokens = tokens->next;
1628 fmt_args_add(stmt, (void*)(intptr_t)'s');
1629 return 1;
1630 } else {
1631 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1632 _error_missing_path, stmt, tokens);
1633 return 0;
1634 }
1635 }
1636
1637 /**
1638 * Parser of a select statement.
1639 * @param stmt the statement object that shall contain the syntax tree
1640 * @param tokens the token list
1641 */
1642 static void dav_parse_select_statement(DavQLStatement *stmt, DavQLToken *tokens) {
1643 stmt->type = DAVQL_SELECT;
1644
1645 // Consume field list
1646 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next), dav_parse_fieldlist(stmt, tokens));
1647 if (stmt->errorcode) {
1648 return;
1649 }
1650
1651 // Consume FROM keyword
1652 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1653 && tokenvalue_is(tokens, "from")) {
1654 tokens = tokens->next;
1655 } else {
1656 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1657 _error_missing_from, stmt, tokens);
1658 return;
1659 }
1660
1661 // Consume path
1662 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next), dav_parse_path(stmt, tokens));
1663 if (stmt->errorcode) {
1664 return;
1665 }
1666 //dav_add_fmt_args(stmt, stmt->path); // add possible path args
1667
1668 // Consume with clause (if any)
1669 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1670 && tokenvalue_is(tokens, "with")) {
1671 tokens = tokens->next;
1672 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next),
1673 dav_parse_with_clause(stmt, tokens));
1674 }
1675 if (stmt->errorcode) {
1676 return;
1677 }
1678
1679 // Consume where clause (if any)
1680 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1681 && tokenvalue_is(tokens, "where")) {
1682 tokens = tokens->next;
1683 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next),
1684 dav_parse_where_clause(stmt, tokens));
1685 } else if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1686 && tokenvalue_is(tokens, "anywhere")) {
1687 // useless, but the user may want to explicitly express his intent
1688 tokens = tokens->next;
1689 stmt->where = NULL;
1690 }
1691 if (stmt->errorcode) {
1692 return;
1693 }
1694
1695 // Consume order by clause (if any)
1696 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1697 && tokenvalue_is(tokens, "order")) {
1698 tokens = tokens->next;
1699 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1700 && tokenvalue_is(tokens, "by")) {
1701 tokens = tokens->next;
1702 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next),
1703 dav_parse_orderby_clause(stmt, tokens));
1704 } else {
1705 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1706 _error_missing_by, stmt, tokens);
1707 return;
1708 }
1709 }
1710 if (stmt->errorcode) {
1711 return;
1712 }
1713
1714
1715 if (tokens) {
1716 if (token_is(tokens, DAVQL_TOKEN_INVALID)) {
1717 dav_error_in_context(DAVQL_ERROR_INVALID_TOKEN,
1718 _error_invalid_token, stmt, tokens);
1719 } else if (!token_is(tokens, DAVQL_TOKEN_END)) {
1720 dav_error_in_context(DAVQL_ERROR_UNEXPECTED_TOKEN,
1721 _error_unexpected_token, stmt, tokens);
1722 }
1723 }
1724 }
1725
1726 static void dav_parse_set_statement(DavQLStatement *stmt, DavQLToken *tokens) {
1727 stmt->type = DAVQL_SET;
1728
1729 // Consume assignments
1730 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next), dav_parse_assignments(stmt, tokens));
1731 if (stmt->errorcode) {
1732 return;
1733 }
1734
1735 // Consume AT keyword
1736 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1737 && tokenvalue_is(tokens, "at")) {
1738 tokens = tokens->next;
1739 } else {
1740 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1741 _error_missing_at, stmt, tokens);
1742 return;
1743 }
1744
1745 // Consume path
1746 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next), dav_parse_path(stmt, tokens));
1747 if (stmt->errorcode) {
1748 return;
1749 }
1750
1751 // Consume with clause (if any)
1752 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1753 && tokenvalue_is(tokens, "with")) {
1754 tokens = tokens->next;
1755 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next),
1756 dav_parse_with_clause(stmt, tokens));
1757 }
1758 if (stmt->errorcode) {
1759 return;
1760 }
1761
1762 // Consume mandatory where clause (or anywhere keyword)
1763 if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1764 && tokenvalue_is(tokens, "where")) {
1765 tokens = tokens->next;
1766 tokens = cx_linked_list_at(tokens, 0, offsetof(DavQLToken, next),
1767 dav_parse_where_clause(stmt, tokens));
1768 } else if (token_is(tokens, DAVQL_TOKEN_KEYWORD)
1769 && tokenvalue_is(tokens, "anywhere")) {
1770 // no-op, but we want the user to be explicit about this
1771 tokens = tokens->next;
1772 stmt->where = NULL;
1773 } else {
1774 dav_error_in_context(DAVQL_ERROR_MISSING_TOKEN,
1775 _error_missing_where, stmt, tokens);
1776 return;
1777 }
1778 }
1779
1780 DavQLStatement* dav_parse_statement(cxstring srctext) {
1781 DavQLStatement *stmt = calloc(1, sizeof(DavQLStatement));
1782
1783 // if we can't even get enough memory for the statement object or an error
1784 // message, we can simply die without returning anything
1785 if (!stmt) {
1786 return NULL;
1787 }
1788 char *oommsg = strdup(_error_out_of_memory);
1789 if (!oommsg) {
1790 free(stmt);
1791 return NULL;
1792 }
1793
1794 // default values
1795 stmt->type = -1;
1796 stmt->depth = 1;
1797
1798 // save trimmed source text
1799 stmt->srctext = cx_strtrim(srctext);
1800
1801 if (stmt->srctext.length) {
1802 // tokenization
1803 DavQLToken* tokens = dav_parse_tokenize(stmt->srctext);
1804
1805 if (tokens) {
1806 // use first token to determine query type
1807
1808 if (tokenvalue_is(tokens, "select")) {
1809 dav_parse_select_statement(stmt, tokens->next);
1810 } else if (tokenvalue_is(tokens, "set")) {
1811 dav_parse_set_statement(stmt, tokens->next);
1812 } else {
1813 stmt->type = DAVQL_ERROR;
1814 stmt->errorcode = DAVQL_ERROR_INVALID;
1815 stmt->errormessage = strdup(_error_invalid);
1816 }
1817
1818 // free token data
1819 tokenlist_free(tokens);
1820 } else {
1821 stmt->errorcode = DAVQL_ERROR_OUT_OF_MEMORY;
1822 }
1823 } else {
1824 stmt->type = DAVQL_ERROR;
1825 stmt->errorcode = DAVQL_ERROR_INVALID;
1826 stmt->errormessage = strdup(_error_invalid);
1827 }
1828
1829 if (stmt->errorcode == DAVQL_ERROR_OUT_OF_MEMORY) {
1830 stmt->type = DAVQL_ERROR;
1831 stmt->errormessage = oommsg;
1832 } else {
1833 free(oommsg);
1834 }
1835
1836 return stmt;
1837 }
1838
1839 void dav_free_statement(DavQLStatement *stmt) {
1840 if(stmt->fields) {
1841 stmt->fields->simple_destructor = (cx_destructor_func)dav_free_field;
1842 cxListDestroy(stmt->fields);
1843 }
1844
1845 if (stmt->where) {
1846 dav_free_expression(stmt->where);
1847 }
1848 if (stmt->errormessage) {
1849 free(stmt->errormessage);
1850 }
1851
1852 if(stmt->orderby) {
1853 stmt->orderby->simple_destructor = (cx_destructor_func)dav_free_order_criterion;
1854 cxListDestroy(stmt->orderby);
1855 }
1856 if(stmt->args) {
1857 cxListDestroy(stmt->args);
1858 }
1859 free(stmt);
1860 }

Mercurial Repository: idav

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