varnish-cache/lib/libvcc/vcc_xref.c
0
/*-
1
 * Copyright (c) 2006 Verdens Gang AS
2
 * Copyright (c) 2006-2011 Varnish Software AS
3
 * All rights reserved.
4
 *
5
 * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
6
 *
7
 * SPDX-License-Identifier: BSD-2-Clause
8
 *
9 80
 * Redistribution and use in source and binary forms, with or without
10
 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
15 80
 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
17
 *
18
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 80
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 80
 * SUCH DAMAGE.
29
 *
30
 * This file contains code for two cross-reference or consistency checks.
31
 *
32
 * The first check is simply that all subroutine, acls and backends are
33
 * both defined and referenced.  Complaints about referenced but undefined
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 * or defined but unreferenced objects will be emitted.
35
 *
36
 * The second check recursively descends through subroutine calls to make
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 * sure that action actions are correct for the methods through which
38
 * they are called.
39
 */
40
41
#include "config.h"
42
43
#include <string.h>
44 80
#include "vcc_compile.h"
45
46
/*--------------------------------------------------------------------*/
47
48
struct proccall {
49
        VTAILQ_ENTRY(proccall)  list;
50 80
        struct symbol           *sym;
51
        struct token            *t;
52
        struct proc             *fm;
53
};
54 80
55
struct procuse {
56
        VTAILQ_ENTRY(procuse)   list;
57
        const struct token      *t1;
58 80
        const struct token      *t2;
59
        const struct symbol     *sym;
60
        const struct xrefuse    *use;
61
        unsigned                mask;
62
        struct proc             *fm;
63 80
};
64
65
/*--------------------------------------------------------------------*/
66
67
static void
68 22256040
vcc_checkref(struct vcc *tl, const struct symbol *sym)
69
{
70 80
71 22256040
        if (sym->noref)
72 19796560
                return;
73 2459480
        if (sym->ndef == 0 && sym->nref != 0) {
74 120
                AN(sym->ref_b);
75 320
                VSB_printf(tl->sb, "Undefined %s %.*s, first reference:\n",
76 120
                    sym->kind->name, PF(sym->ref_b));
77 120
                vcc_ErrWhere(tl, sym->ref_b);
78 2459480
        } else if (sym->ndef != 0 && sym->nref == 0) {
79 5160
                AN(sym->def_b);
80 10160
                VSB_printf(tl->sb, "Unused %s %.*s, defined:\n",
81 5080
                    sym->kind->name, PF(sym->def_b));
82 5080
                vcc_ErrWhere(tl, sym->def_b);
83 5080
                if (!tl->err_unref)
84 4840
                        vcc_Warn(tl);
85 5080
        }
86 22256040
}
87
88
int
89 110600
vcc_CheckReferences(struct vcc *tl)
90
{
91
92 110520
        VCC_WalkSymbols(tl, vcc_checkref, SYM_MAIN, SYM_NONE);
93 110520
        return (tl->err);
94 80
}
95
96
/*--------------------------------------------------------------------
97
 * Returns checks
98
 */
99
100
const struct xrefuse XREF_READ[1] = {{"xref_read", "Not available"}};
101
const struct xrefuse XREF_WRITE[1] = {{"xref_write", "Cannot be set"}};
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const struct xrefuse XREF_UNSET[1] = {{"xref_unset", "Cannot be unset"}};
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const struct xrefuse XREF_ACTION[1] = {{"xref_action", "Not a valid action"}};
104 80
105
void
106 6724080
vcc_AddUses(struct vcc *tl, const struct token *t1, const struct token *t2,
107
    const struct symbol *sym, const struct xrefuse *use)
108
{
109
        struct procuse *pu;
110
111 6724080
        AN(tl->curproc);
112 6724080
        pu = TlAlloc(tl, sizeof *pu);
113 6724080
        AN(pu);
114 6724080
        AN(sym);
115 6724080
        AN(use);
116 6724080
        AN(use->name);
117 6724080
        pu->t1 = t1;
118 6724080
        pu->t2 = t2;
119 6724080
        if (pu->t2 == NULL) {
120 5397480
                pu->t2 = vcc_PeekTokenFrom(tl, t1);
121 5397480
                AN(pu->t2);
122 5397480
        }
123 6724080
        pu->sym = sym;
124 6724080
        pu->use = use;
125 6724080
        pu->fm = tl->curproc;
126
127 6724080
        if (pu->use == XREF_READ)
128 5056920
                pu->mask = sym->r_methods;
129 1667160
        else if (pu->use == XREF_WRITE)
130 1103360
                pu->mask = sym->w_methods;
131 563800
        else if (pu->use == XREF_UNSET)
132 223240
                pu->mask = sym->u_methods;
133 340560
        else if (pu->use == XREF_ACTION)
134 340560
                pu->mask = sym->action_mask;
135
        else
136 0
                WRONG("wrong xref use");
137
138 6724080
        VTAILQ_INSERT_TAIL(&tl->curproc->uses, pu, list);
139 6724080
}
140
141
void
142 2768400
vcc_AddCall(struct vcc *tl, struct token *t, struct symbol *sym)
143
{
144
        struct proccall *pc;
145
146 2768400
        AN(sym);
147 2768400
        pc = TlAlloc(tl, sizeof *pc);
148 2768400
        AN(pc);
149 2768400
        pc->sym = sym;
150 2768400
        pc->t = t;
151 2768400
        pc->fm = tl->curproc;
152 2768400
        VTAILQ_INSERT_TAIL(&tl->curproc->calls, pc, list);
153 2768400
}
154
155
void
156 2455400
vcc_ProcAction(struct proc *p, unsigned returns, unsigned mask, struct token *t)
157
{
158
159 2455400
        assert(returns < VCL_RET_MAX);
160 2455400
        p->ret_bitmap |= (1U << returns);
161 2455400
        p->okmask &= mask;
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        /* Record the first instance of this return */
163 2455400
        if (p->return_tok[returns] == NULL)
164 2448520
                p->return_tok[returns] = t;
165 2455400
}
166
167
static int
168 8594960
vcc_CheckActionRecurse(struct vcc *tl, struct proc *p, unsigned bitmap)
169
{
170
        unsigned u;
171
        struct proccall *pc;
172
173 8594960
        AN(p);
174 8594960
        if (p->active) {
175 80
                VSB_cat(tl->sb, "Subroutine recurses on\n");
176 80
                vcc_ErrWhere(tl, p->name);
177 80
                return (1);
178
        }
179 8594880
        u = p->ret_bitmap & ~bitmap;
180 8594880
        if (u) {
181
182
#define VCL_RET_MAC(l, U, B)                                            \
183
                if (u & (1 << (VCL_RET_##U))) {                         \
184
                        VSB_printf(tl->sb, "Invalid return \"" #l "\"\n");\
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                        vcc_ErrWhere(tl, p->return_tok[VCL_RET_##U]);   \
186
                }
187
#include "tbl/vcl_returns.h"
188
189
                VSB_printf(tl->sb, "\n...in subroutine \"%.*s\"\n",
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                    PF(p->name));
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                vcc_ErrWhere(tl, p->name);
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                return (1);
193
        }
194
195
        // more references than calls -> sub is referenced for dynamic calls
196 8594840
        u = (p->sym->nref > p->called);
197
198 8594840
        p->active = 1;
199 13224240
        VTAILQ_FOREACH(pc, &p->calls, list) {
200 4629560
                if (pc->sym->proc == NULL) {
201 0
                        VSB_printf(tl->sb, "Subroutine %s does not exist\n",
202 0
                            pc->sym->name);
203 0
                        vcc_ErrWhere(tl, pc->t);
204 0
                        return (1);
205
                }
206 4629560
                pc->sym->proc->calledfrom |= p->calledfrom;
207 4629560
                pc->sym->proc->called++;
208 4629560
                pc->sym->nref += u;
209 4629560
                if (vcc_CheckActionRecurse(tl, pc->sym->proc, bitmap)) {
210 320
                        VSB_printf(tl->sb, "\n...called from \"%.*s\"\n",
211 160
                            PF(p->name));
212 160
                        vcc_ErrWhere(tl, pc->t);
213 160
                        return (1);
214
                }
215 4629400
                p->okmask &= pc->sym->proc->okmask;
216 4629400
        }
217 8594680
        p->active = 0;
218 8594680
        return (0);
219 8594960
}
220
221
/*--------------------------------------------------------------------*/
222
223
static void
224 3965400
vcc_checkaction(struct vcc *tl, const struct symbol *sym)
225
{
226
        struct proc *p;
227
        unsigned bitmap;
228
229 3965400
        p = sym->proc;
230 3965400
        AN(p);
231 3965400
        AN(p->name);
232
233 3965400
        if (p->method == NULL) {
234 2424320
                bitmap = ~0U;
235 2424320
        } else {
236 1541080
                bitmap = p->method->ret_bitmap;
237 1541080
                p->calledfrom = p->method->bitval;
238
        }
239
240 3965400
        if (! vcc_CheckActionRecurse(tl, p, bitmap))
241 3965280
                return;
242
243 120
        tl->err = 1;
244 120
        if (p->method == NULL)
245 80
                return;
246
247 80
        VSB_printf(tl->sb,
248 40
                   "\n...which is the \"%s\" subroutine\n", p->method->name);
249 40
        VSB_cat(tl->sb, "Legal returns are:");
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#define VCL_RET_MAC(l, U, B)                                            \
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        if (p->method->ret_bitmap & ((1 << VCL_RET_##U)))               \
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                VSB_printf(tl->sb, " \"%s\"", #l);
253
254
#include "tbl/vcl_returns.h"
255
        VSB_cat(tl->sb, "\n");
256
}
257
258
int
259 110160
vcc_CheckAction(struct vcc *tl)
260
{
261
262 110160
        VCC_WalkSymbols(tl, vcc_checkaction, SYM_MAIN, SYM_SUB);
263 110160
        return (tl->err);
264
}
265
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/*--------------------------------------------------------------------*/
267
268
static struct procuse *
269 7604520
vcc_illegal_write(struct vcc *tl, struct procuse *pu, const struct method *m)
270
{
271
272 7604520
        if (pu->mask || pu->use != XREF_WRITE)
273 7604000
                return (NULL);
274
275 520
        if (pu->sym->r_methods == 0) {
276 40
                vcc_ErrWhere2(tl, pu->t1, pu->t2);
277 40
                VSB_cat(tl->sb, "Variable cannot be set.\n");
278 40
                return (NULL);
279
        }
280
281 480
        if (!(pu->sym->r_methods & m->bitval)) {
282 80
                pu->use = XREF_READ; /* NB: change the error message. */
283 80
                return (pu);
284
        }
285
286 400
        vcc_ErrWhere2(tl, pu->t1, pu->t2);
287 400
        VSB_cat(tl->sb, "Variable is read only.\n");
288 400
        return (NULL);
289 7604520
}
290
291
static struct procuse *
292 12488440
vcc_FindIllegalUse(struct vcc *tl, struct proc *p, const struct method *m)
293
{
294 12488440
        struct procuse *pu, *pw, *r = NULL;
295
296 37619800
        VTAILQ_FOREACH(pu, &p->uses, list) {
297 25131360
                p->okmask &= pu->mask;
298 25131360
                if (m == NULL)
299 17526840
                        continue;
300 7604520
                pw = vcc_illegal_write(tl, pu, m);
301 7604520
                if (r != NULL)
302 280
                        continue;
303 7604240
                if (tl->err)
304 440
                        r = pw;
305 7603800
                else if (!(pu->mask & m->bitval))
306 1160
                        r = pu;
307 7604240
        }
308 12488440
        return (r);
309
}
310
311
static int
312 8545520
vcc_CheckUseRecurse(struct vcc *tl, struct proc *p,
313
    const struct method *m)
314
{
315
        struct proccall *pc;
316
        struct procuse *pu;
317
318 8545520
        pu = vcc_FindIllegalUse(tl, p, m);
319 8545520
        if (pu != NULL) {
320 120
                vcc_ErrWhere2(tl, pu->t1, pu->t2);
321 240
                VSB_printf(tl->sb, "%s from subroutine '%s'.\n",
322 120
                    pu->use->err, m->name);
323 240
                VSB_printf(tl->sb, "\n...in subroutine \"%.*s\"\n",
324 120
                    PF(pu->fm->name));
325 120
                vcc_ErrWhere(tl, p->name);
326 120
                return (1);
327
        }
328 8545400
        if (tl->err)
329 40
                return (1);
330 13149200
        VTAILQ_FOREACH(pc, &p->calls, list) {
331 4604040
                if (vcc_CheckUseRecurse(tl, pc->sym->proc, m)) {
332 400
                        VSB_printf(tl->sb, "\n...called from \"%.*s\"\n",
333 200
                            PF(p->name));
334 200
                        vcc_ErrWhere(tl, pc->t);
335 200
                        return (1);
336
                }
337 4603840
                p->okmask &= pc->sym->proc->okmask;
338 4603840
        }
339 8545160
        return (0);
340 8545520
}
341
342
static void
343 3942920
vcc_checkuses(struct vcc *tl, const struct symbol *sym)
344
{
345
        struct proc *p;
346
        struct procuse *pu;
347
348 3942920
        p = sym->proc;
349 3942920
        AN(p);
350 3942920
        pu = vcc_FindIllegalUse(tl, p, p->method);
351 3942920
        if (pu != NULL) {
352 1040
                vcc_ErrWhere2(tl, pu->t1, pu->t2);
353 2080
                VSB_printf(tl->sb, "%s in subroutine '%.*s'.",
354 1040
                    pu->use->err, PF(p->name));
355 1040
                VSB_cat(tl->sb, "\nAt: ");
356 1040
                return;
357
        }
358 3941880
        ERRCHK(tl);
359 3941480
        if (vcc_CheckUseRecurse(tl, p, p->method)) {
360 320
                VSB_printf(tl->sb,
361 160
                    "\n...which is the \"%s\" subroutine\n", p->method->name);
362 160
                return;
363
        }
364 3942920
}
365
366
/*
367
 * Used from a second symbol walk because vcc_checkuses is more precise for
368
 * subroutines called from methods. We catch here subs used for dynamic calls
369
 * and with vcc_err_unref = off
370
 */
371
static void
372 3903360
vcc_checkpossible(struct vcc *tl, const struct symbol *sym)
373
{
374
        struct proc *p;
375
376 3903360
        p = sym->proc;
377 3903360
        AN(p);
378
379 3903360
        if (p->okmask != 0)
380 3903280
                return;
381
382 80
        VSB_cat(tl->sb, "Impossible Subroutine");
383 80
        vcc_ErrWhere(tl, p->name);
384 3903360
}
385
386
int
387 110040
vcc_CheckUses(struct vcc *tl)
388
{
389
390 110040
        VCC_WalkSymbols(tl, vcc_checkuses, SYM_MAIN, SYM_SUB);
391 110040
        if (tl->err)
392 1600
                return (tl->err);
393 108440
        VCC_WalkSymbols(tl, vcc_checkpossible, SYM_MAIN, SYM_SUB);
394 108440
        return (tl->err);
395 110040
}
396
397
/*---------------------------------------------------------------------*/
398
399
static void v_matchproto_(symwalk_f)
400 7760
vcc_instance_info(struct vcc *tl, const struct symbol *sym)
401
{
402
403 7760
        CHECK_OBJ_NOTNULL(sym, SYMBOL_MAGIC);
404 7760
        AN(sym->rname);
405 7760
        Fc(tl, 0, "\t{ .p = (uintptr_t *)&%s, .name = \"", sym->rname);
406 7760
        VCC_SymName(tl->fc, sym);
407 7760
        Fc(tl, 0, "\" },\n");
408 7760
}
409
410
void
411 48360
VCC_InstanceInfo(struct vcc *tl)
412
{
413 48360
        Fc(tl, 0, "\nstatic const struct vpi_ii VGC_instance_info[] = {\n");
414 48360
        VCC_WalkSymbols(tl, vcc_instance_info, SYM_MAIN, SYM_INSTANCE);
415 48360
        Fc(tl, 0, "\t{ .p = NULL, .name = \"\" }\n");
416 48360
        Fc(tl, 0, "};\n");
417 48360
}
418
419
/*---------------------------------------------------------------------*/
420
421
static int sym_type_len;
422
423
static void v_matchproto_(symwalk_f)
424 10761120
vcc_xreftable_len(struct vcc *tl, const struct symbol *sym)
425
{
426
        int len;
427
428 10761120
        (void)tl;
429 10761120
        CHECK_OBJ_NOTNULL(sym, SYMBOL_MAGIC);
430 10761120
        CHECK_OBJ_NOTNULL(sym->type, TYPE_MAGIC);
431 10761120
        len = strlen(sym->type->name);
432 10761120
        if (sym_type_len < len)
433 302240
                sym_type_len = len;
434 10761120
}
435
436
static void v_matchproto_(symwalk_f)
437 10761120
vcc_xreftable(struct vcc *tl, const struct symbol *sym)
438
{
439
440 10761120
        CHECK_OBJ_NOTNULL(sym, SYMBOL_MAGIC);
441 10761120
        CHECK_OBJ_NOTNULL(sym->kind, KIND_MAGIC);
442 10761120
        CHECK_OBJ_NOTNULL(sym->type, TYPE_MAGIC);
443 10761120
        Fc(tl, 0, " * %-8s ", sym->kind->name);
444 10761120
        Fc(tl, 0, " %-*s ", sym_type_len, sym->type->name);
445 10761120
        Fc(tl, 0, " %2u %2u ", sym->lorev, sym->hirev);
446 10761120
        VCC_SymName(tl->fc, sym);
447 10761120
        if (sym->wildcard != NULL)
448 290160
                Fc(tl, 0, "*");
449 10761120
        Fc(tl, 0, "\n");
450 10761120
}
451
452
void
453 48360
VCC_XrefTable(struct vcc *tl)
454
{
455
456
#define VCC_NAMESPACE(U, l)                                             \
457
        Fc(tl, 0, "\n/*\n * Symbol Table " #U "\n *\n");                \
458
        sym_type_len = 0;                                               \
459
        VCC_WalkSymbols(tl, vcc_xreftable_len, SYM_##U, SYM_NONE);      \
460
        VCC_WalkSymbols(tl, vcc_xreftable, SYM_##U, SYM_NONE);          \
461
        Fc(tl, 0, "*/\n\n");
462
#include "vcc_namespace.h"
463
}