git.ozlabs.org Git - ccan/blob - tools/ccanlint/tests/examples_compile.c

   1 #include <tools/ccanlint/ccanlint.h>
   2 #include <tools/tools.h>
   3 #include <ccan/talloc/talloc.h>
   4 #include <ccan/str/str.h>
   5 #include <sys/types.h>
   6 #include <sys/stat.h>
   7 #include <fcntl.h>
   8 #include <stdint.h>
   9 #include <string.h>
  10 #include <unistd.h>
  11 #include <ctype.h>
  12 #include <assert.h>
  13
  14 static const char *can_run(struct manifest *m)
  15 {
  16         if (safe_mode)
  17                 return "Safe mode enabled";
  18         return NULL;
  19 }
  20
  21 /* FIXME: We should build if it doesn't exist... */
  22 static bool expect_obj_file(const char *dir)
  23 {
  24         struct manifest *dep_man;
  25         bool has_c_files;
  26
  27         dep_man = get_manifest(dir, dir);
  28
  29         /* If it has C files, we expect an object file built from them. */
  30         has_c_files = !list_empty(&dep_man->c_files);
  31         talloc_free(dep_man);
  32         return has_c_files;
  33 }
  34
  35 static char *add_dep(const struct manifest *m, char *list, const char *mod)
  36 {
  37         char **deps, *obj;
  38         unsigned int i;
  39
  40         /* Not ourselves. */
  41         if (streq(m->basename, mod))
  42                 return list;
  43
  44         /* Not if there's no object file for that module */
  45         if (!expect_obj_file(talloc_asprintf(list, "%s/ccan/%s", ccan_dir,mod)))
  46                 return list;
  47
  48         obj = talloc_asprintf(list, "%s/ccan/%s.o", ccan_dir, mod);
  49
  50         /* Not anyone we've already included. */
  51         if (strstr(list, obj))
  52                 return list;
  53
  54         list = talloc_asprintf_append(list, " %s", obj);
  55
  56         /* Get that modules depends as well... */
  57         assert(!safe_mode);
  58         deps = get_deps(m, talloc_asprintf(list, "%s/ccan/%s", ccan_dir, mod),
  59                         false, NULL);
  60
  61         for (i = 0; deps[i]; i++) {
  62                 if (strstarts(deps[i], "ccan/"))
  63                         list = add_dep(m, list, deps[i] + strlen("ccan/"));
  64         }
  65         return list;
  66 }
  67
  68 static char *obj_list(const struct manifest *m, struct ccan_file *f)
  69 {
  70         char *list = talloc_strdup(m, "");
  71         struct ccan_file *i;
  72         char **lines;
  73
  74         /* Object files for this module. */
  75         list_for_each(&m->c_files, i, list)
  76                 list = talloc_asprintf_append(list, " %s", i->compiled);
  77
  78         /* Other ccan modules we depend on. */
  79         list_for_each(&m->dep_dirs, i, list) {
  80                 if (i->compiled)
  81                         list = talloc_asprintf_append(list, " %s", i->compiled);
  82         }
  83
  84         /* Other modules implied by includes. */
  85         for (lines = get_ccan_file_lines(f); *lines; lines++) {
  86                 unsigned preflen = strspn(*lines, " \t");
  87                 if (strstarts(*lines + preflen, "#include <ccan/")) {
  88                         const char *mod;
  89                         unsigned modlen;
  90
  91                         mod = *lines + preflen + strlen("#include <ccan/");
  92                         modlen = strcspn(mod, "/");
  93                         mod = talloc_strndup(f, mod, modlen);
  94                         list = add_dep(m, list, mod);
  95                 }
  96         }
  97
  98         return list;
  99 }
 100
 101 static char *lib_list(const struct manifest *m)
 102 {
 103         unsigned int i, num;
 104         char **libs = get_libs(m, ".", &num, &m->info_file->compiled);
 105         char *ret = talloc_strdup(m, "");
 106
 107         for (i = 0; i < num; i++)
 108                 ret = talloc_asprintf_append(ret, "-l%s ", libs[i]);
 109         return ret;
 110 }
 111
 112 static char *compile(const void *ctx,
 113                      struct manifest *m,
 114                      struct ccan_file *file,
 115                      bool keep)
 116 {
 117         char *errmsg;
 118
 119         file->compiled = maybe_temp_file(ctx, "", keep, file->fullname);
 120         errmsg = compile_and_link(ctx, file->fullname, ccan_dir,
 121                                   obj_list(m, file),
 122                                   "", lib_list(m), file->compiled);
 123         if (errmsg) {
 124                 talloc_free(file->compiled);
 125                 file->compiled = NULL;
 126                 return errmsg;
 127         }
 128         return NULL;
 129 }
 130
 131 struct score {
 132         unsigned int score;
 133         char *errors;
 134 };
 135
 136 static char *start_main(char *ret, const char *why)
 137 {
 138         return talloc_asprintf_append(ret,
 139               "/* The example %s, so fake function wrapper inserted */\n"
 140               "int main(int argc, char *argv[])\n"
 141               "{\n", why);
 142 }
 143
 144 /* We only handle simple function definitions here. */
 145 static char *add_func(char *others, const char *line)
 146 {
 147         const char *p, *end = strchr(line, '(') - 1;
 148         while (isblank(*end)) {
 149                 end--;
 150                 if (end == line)
 151                         return others;
 152         }
 153
 154         for (p = end; isalnum(*p) || *p == '_'; p--) {
 155                 if (p == line)
 156                         return others;
 157         }
 158
 159         return talloc_asprintf_append(others, "printf(\"%%p\", %.*s);\n",
 160                                       (unsigned)(end - p + 1), p);
 161 }
 162
 163 static void strip_leading_whitespace(char **lines)
 164 {
 165         unsigned int i, min_span = -1U;
 166
 167         for (i = 0; lines[i]; i++) {
 168                 unsigned int span = strspn(lines[i], " \t");
 169                 /* All whitespace?  Ignore */
 170                 if (!lines[i][span])
 171                         continue;
 172                 if (span < min_span)
 173                         min_span = span;
 174         }
 175
 176         for (i = 0; lines[i]; i++)
 177                 if (strlen(lines[i]) >= min_span)
 178                         lines[i] += min_span;
 179 }
 180
 181 static bool looks_internal(char **lines, char **why)
 182 {
 183         unsigned int i;
 184         bool last_ended = true; /* Did last line finish a statement? */
 185
 186         for (i = 0; lines[i]; i++) {
 187                 /* Skip leading whitespace. */
 188                 const char *line = lines[i] + strspn(lines[i], " \t");
 189                 unsigned len = strspn(line, IDENT_CHARS);
 190
 191                 if (!line[0] || isblank(line[0]) || strstarts(line, "//"))
 192                         continue;
 193
 194                 /* The winners. */
 195                 if (strstarts(line, "if") && len == 2) {
 196                         *why = "starts with if";
 197                         return true;
 198                 }
 199                 if (strstarts(line, "for") && len == 3) {
 200                         *why = "starts with for";
 201                         return true;
 202                 }
 203                 if (strstarts(line, "while") && len == 5) {
 204                         *why = "starts with while";
 205                         return true;
 206                 }
 207                 if (strstarts(line, "do") && len == 2) {
 208                         *why = "starts with do";
 209                         return true;
 210                 }
 211
 212                 /* The losers. */
 213                 if (strstarts(line, "#include")) {
 214                         *why = "starts with #include";
 215                         return false;
 216                 }
 217
 218                 if (last_ended && strchr(line, '(')) {
 219                         if (strstarts(line, "static")) {
 220                                 *why = "starts with static and contains (";
 221                                 return false;
 222                         }
 223                         if (strends(line, ")")) {
 224                                 *why = "contains ( and ends with )";
 225                                 return false;
 226                         }
 227                 }
 228
 229                 /* Single identifier then operator == inside function. */
 230                 if (last_ended && len
 231                     && ispunct(line[len+strspn(line+len, " ")])) {
 232                         *why = "starts with identifier then punctuation";
 233                         return true;
 234                 }
 235
 236                 last_ended = (strends(line, "}")
 237                               || strends(line, ";")
 238                               || streq(line, "..."));
 239         }
 240
 241         /* No idea... Say yes? */
 242         *why = "gave no clues";
 243         return true;
 244 }
 245
 246 /* Examples will often build on prior ones.  Try combining them. */
 247 static char **combine(const void *ctx, char **lines, char **prev)
 248 {
 249         unsigned int i, lines_total, prev_total, count;
 250         char **ret;
 251         const char *reasoning;
 252         char *why = NULL;
 253
 254         if (!prev)
 255                 return NULL;
 256
 257         /* If it looks internal, put prev at start. */
 258         if (looks_internal(lines, &why)) {
 259                 count = 0;
 260                 reasoning = "seemed to belong inside a function";
 261         } else {
 262                 /* Try inserting in first elided position */
 263                 for (count = 0; lines[count]; count++) {
 264                         if (strcmp(lines[count], "...") == 0)
 265                                 break;
 266                 }
 267                 if (!lines[count]) {
 268                         /* Try at start anyway? */
 269                         count = 0;
 270                         reasoning = "didn't seem to belong inside"
 271                                 " a function, so we prepended the previous"
 272                                 " example";
 273                 } else {
 274                         reasoning = "didn't seem to belong inside"
 275                                 " a function, so we put the previous example"
 276                                 " at the first ...";
 277
 278                         count++;
 279                 }
 280         }
 281
 282         for (i = 0; lines[i]; i++);
 283         lines_total = i;
 284
 285         for (i = 0; prev[i]; i++);
 286         prev_total = i;
 287
 288         ret = talloc_array(ctx, char *, 1 +lines_total + prev_total + 1);
 289         ret[0] = talloc_asprintf(ret, "/* The example %s, thus %s */\n",
 290                                  why, reasoning);
 291         memcpy(ret+1, lines, count * sizeof(ret[0]));
 292         memcpy(ret+1 + count, prev, prev_total * sizeof(ret[0]));
 293         memcpy(ret+1 + count + prev_total, lines + count,
 294                (lines_total - count + 1) * sizeof(ret[0]));
 295         return ret;
 296 }
 297
 298 static char *mangle(struct manifest *m, char **lines)
 299 {
 300         char *ret, *use_funcs = NULL, *why;
 301         bool in_function = false, fake_function = false, has_main = false;
 302         unsigned int i;
 303
 304         ret = talloc_strdup(m, "/* Prepend a heap of headers. */\n"
 305                             "#include <assert.h>\n"
 306                             "#include <err.h>\n"
 307                             "#include <errno.h>\n"
 308                             "#include <fcntl.h>\n"
 309                             "#include <limits.h>\n"
 310                             "#include <stdbool.h>\n"
 311                             "#include <stdint.h>\n"
 312                             "#include <stdio.h>\n"
 313                             "#include <stdlib.h>\n"
 314                             "#include <string.h>\n"
 315                             "#include <sys/stat.h>\n"
 316                             "#include <sys/types.h>\n"
 317                             "#include <unistd.h>\n");
 318         ret = talloc_asprintf_append(ret, "/* Include header from module. */\n"
 319                                      "#include <ccan/%s/%s.h>\n",
 320                                      m->basename, m->basename);
 321
 322         ret = talloc_asprintf_append(ret, "/* Useful dummy functions. */\n"
 323                                      "extern int somefunc(void);\n"
 324                                      "int somefunc(void) { return 0; }\n"
 325                                      "extern char somestring[];\n"
 326                                      "char somestring[] = \"hello world\";\n");
 327
 328         if (looks_internal(lines, &why)) {
 329                 /* Wrap it all in main(). */
 330                 ret = start_main(ret, why);
 331                 fake_function = true;
 332                 in_function = true;
 333                 has_main = true;
 334         } else
 335                 ret = talloc_asprintf_append(ret,
 336                              "/* The example %s, so didn't wrap in main() */\n",
 337                                      why);
 338
 339         /* Primitive, very primitive. */
 340         for (i = 0; lines[i]; i++) {
 341                 /* } at start of line ends a function. */
 342                 if (in_function) {
 343                         if (lines[i][0] == '}')
 344                                 in_function = false;
 345                 } else {
 346                         /* Character at start of line, with ( and no ;
 347                          * == function start.  Ignore comments. */
 348                         if (!isblank(lines[i][0])
 349                             && strchr(lines[i], '(')
 350                             && !strchr(lines[i], ';')
 351                             && !strstr(lines[i], "//")) {
 352                                 in_function = true;
 353                                 if (strncmp(lines[i], "int main", 8) == 0)
 354                                         has_main = true;
 355                                 if (strncmp(lines[i], "static", 6) == 0) {
 356                                         use_funcs = add_func(use_funcs,
 357                                                              lines[i]);
 358                                 }
 359                         }
 360                 }
 361                 /* ... means elided code. */
 362                 if (strcmp(lines[i], "...") == 0) {
 363                         if (!in_function && !has_main
 364                             && looks_internal(lines + i + 1, &why)) {
 365                                 /* This implies we start a function here. */
 366                                 ret = start_main(ret, why);
 367                                 has_main = true;
 368                                 fake_function = true;
 369                                 in_function = true;
 370                         }
 371                         ret = talloc_asprintf_append(ret,
 372                                                      "/* ... removed */\n");
 373                         continue;
 374                 }
 375                 ret = talloc_asprintf_append(ret, "%s\n", lines[i]);
 376         }
 377
 378         if (!has_main) {
 379                 ret = talloc_asprintf_append(ret,
 380                              "/* Need a main to link successfully. */\n"
 381                              "int main(void)\n{\n");
 382                 fake_function = true;
 383         }
 384
 385         if (use_funcs) {
 386                 ret = talloc_asprintf_append(ret,
 387                                              "/* Get rid of unused warnings"
 388                                              " by printing addresses of"
 389                                              " static funcs. */");
 390                 if (!fake_function) {
 391                         ret = talloc_asprintf_append(ret,
 392                                                      "int use_funcs(void);\n"
 393                                                      "int use_funcs(void) {\n");
 394                         fake_function = true;
 395                 }
 396                 ret = talloc_asprintf_append(ret, "     %s\n", use_funcs);
 397         }
 398
 399         if (fake_function)
 400                 ret = talloc_asprintf_append(ret, "return 0;\n"
 401                                              "}\n");
 402         return ret;
 403 }
 404
 405 static struct ccan_file *mangle_example(struct manifest *m,
 406                                         struct ccan_file *example,
 407                                         char **lines,
 408                                         bool keep)
 409 {
 410         char *name, *contents;
 411         int fd;
 412         struct ccan_file *f;
 413
 414         name = maybe_temp_file(example, ".c", keep,
 415                                talloc_asprintf(m, "%s/mangled-%s",
 416                                                m->dir, example->name));
 417         f = new_ccan_file(example,
 418                           talloc_dirname(example, name),
 419                           talloc_basename(example, name));
 420         talloc_steal(f, name);
 421
 422         fd = open(f->fullname, O_WRONLY | O_CREAT | O_EXCL, 0600);
 423         if (fd < 0)
 424                 return NULL;
 425
 426         contents = mangle(m, lines);
 427         if (write(fd, contents, strlen(contents)) != strlen(contents)) {
 428                 close(fd);
 429                 return NULL;
 430         }
 431         close(fd);
 432         f->contents = talloc_steal(f, contents);
 433         list_add(&m->mangled_examples, &f->list);
 434         return f;
 435 }
 436
 437 static void *build_examples(struct manifest *m, bool keep,
 438                             unsigned int *timeleft)
 439 {
 440         struct ccan_file *i;
 441         struct score *score = talloc(m, struct score);
 442         char **prev = NULL;
 443
 444         score->score = 0;
 445         score->errors = talloc_strdup(score, "");
 446
 447         examples_compile.total_score = 0;
 448         list_for_each(&m->examples, i, list) {
 449                 char *ret, *ret1 = NULL, *ret2;
 450                 struct ccan_file *mangle1 = NULL, *mangle2;
 451
 452                 examples_compile.total_score++;
 453                 /* Simplify our dumb parsing. */
 454                 strip_leading_whitespace(get_ccan_file_lines(i));
 455                 ret = compile(i, m, i, keep);
 456                 if (!ret) {
 457                         prev = get_ccan_file_lines(i);
 458                         score->score++;
 459                         continue;
 460                 }
 461
 462                 /* Try standalone. */
 463                 mangle1 = mangle_example(m, i, get_ccan_file_lines(i), keep);
 464                 ret1 = compile(i, m, mangle1, keep);
 465                 if (!ret1) {
 466                         prev = get_ccan_file_lines(i);
 467                         score->score++;
 468                         continue;
 469                 }
 470
 471                 /* Try combining with previous (successful) example... */
 472                 if (prev) {
 473                         char **new = combine(i, get_ccan_file_lines(i), prev);
 474
 475                         mangle2 = mangle_example(m, i, new, keep);
 476                         ret2 = compile(i, m, mangle1, keep);
 477                         if (!ret2) {
 478                                 prev = new;
 479                                 score->score++;
 480                                 continue;
 481                         }
 482                 }
 483
 484                 score->errors = talloc_asprintf_append(score->errors,
 485                                        "%s: tried standalone example:\n"
 486                                        "%s\n"
 487                                        "Errors: %s\n\n",
 488                                        i->name,
 489                                        get_ccan_file_contents(i),
 490                                        ret);
 491                 score->errors = talloc_asprintf_append(score->errors,
 492                                        "%s: tried adding headers, wrappers:\n"
 493                                        "%s\n"
 494                                        "Errors: %s\n\n",
 495                                        i->name,
 496                                        get_ccan_file_contents(mangle1),
 497                                        ret1);
 498
 499                 if (mangle2) {
 500                         score->errors = talloc_asprintf_append(score->errors,
 501                                        "%s\n"
 502                                        "%s: tried combining with"
 503                                        " previous example:\n"
 504                                        "Errors: %s\n\n",
 505                                        i->name,
 506                                        get_ccan_file_contents(mangle2),
 507                                        ret2);
 508                 }
 509                 /* This didn't work, so not a candidate for combining. */
 510                 prev = NULL;
 511         }
 512
 513         if (strcmp(score->errors, "") == 0) {
 514                 talloc_free(score);
 515                 return NULL;
 516         }
 517         return score;
 518 }
 519
 520 static unsigned int score_examples(struct manifest *m, void *check_result)
 521 {
 522         struct score *score = check_result;
 523         return score->score;
 524 }
 525
 526 static const char *describe(struct manifest *m, void *check_result)
 527 {
 528         struct score *score = check_result;
 529         if (verbose >= 2 && score->errors)
 530                 return talloc_asprintf(m, "Compile errors building examples:\n"
 531                                        "%s", score->errors);
 532         return NULL;
 533 }
 534
 535 struct ccanlint examples_compile = {
 536         .key = "examples-compile",
 537         .name = "Module examples compile",
 538         .score = score_examples,
 539         .total_score = 3, /* This gets changed to # examples, if they exist */
 540         .check = build_examples,
 541         .describe = describe,
 542         .can_run = can_run,
 543 };
 544
 545 REGISTER_TEST(examples_compile, &has_examples, NULL);