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