git.ozlabs.org Git - ccan/blob - tools/configurator/configurator.c

   1 /* Simple tool to create config.h.
   2  * Would be much easier with ccan modules, but deliberately standalone. */
   3 #include <stdio.h>
   4 #include <stdbool.h>
   5 #include <stdlib.h>
   6 #include <unistd.h>
   7 #include <err.h>
   8 #include <sys/types.h>
   9 #include <sys/wait.h>
  10 #include <sys/stat.h>
  11 #include <fcntl.h>
  12 #include <string.h>
  13
  14 #define DEFAULT_COMPILER "cc"
  15 #define DEFAULT_FLAGS "-g -Wall -Wundef -Wmissing-prototypes -Wmissing-declarations -Wstrict-prototypes -Wold-style-definition"
  16
  17 #define OUTPUT_FILE "configurator.out"
  18 #define INPUT_FILE "configuratortest.c"
  19
  20 static int verbose;
  21
  22 enum test_style {
  23         OUTSIDE_MAIN            = 0x1,
  24         DEFINES_FUNC            = 0x2,
  25         INSIDE_MAIN             = 0x4,
  26         DEFINES_EVERYTHING      = 0x8,
  27         MAY_NOT_COMPILE         = 0x10,
  28         EXECUTE                 = 0x8000
  29 };
  30
  31 struct test {
  32         const char *name;
  33         enum test_style style;
  34         const char *depends;
  35         const char *fragment;
  36         bool done;
  37         bool answer;
  38 };
  39
  40 static struct test tests[] = {
  41         { "HAVE_32BIT_OFF_T", DEFINES_EVERYTHING|EXECUTE, NULL,
  42           "#include <sys/types.h>\n"
  43           "int main(int argc, char *argv[]) {\n"
  44           "     return sizeof(off_t) == 4 ? 0 : 1;\n"
  45           "}\n" },
  46         { "HAVE_ALIGNOF", INSIDE_MAIN, NULL,
  47           "return __alignof__(double) > 0 ? 0 : 1;" },
  48         { "HAVE_ASPRINTF", DEFINES_FUNC, NULL,
  49           "#define _GNU_SOURCE\n"
  50           "#include <stdio.h>\n"
  51           "static char *func(int x) {"
  52           "     char *p;\n"
  53           "     if (asprintf(&p, \"%u\", x) == -1) p = NULL;"
  54           "     return p;\n"
  55           "}" },
  56         { "HAVE_ATTRIBUTE_COLD", DEFINES_FUNC, NULL,
  57           "static int __attribute__((cold)) func(int x) { return x; }" },
  58         { "HAVE_ATTRIBUTE_CONST", DEFINES_FUNC, NULL,
  59           "static int __attribute__((const)) func(int x) { return x; }" },
  60         { "HAVE_ATTRIBUTE_MAY_ALIAS", OUTSIDE_MAIN, NULL,
  61           "typedef short __attribute__((__may_alias__)) short_a;" },
  62         { "HAVE_ATTRIBUTE_NORETURN", DEFINES_FUNC, NULL,
  63           "#include <stdlib.h>\n"
  64           "static void __attribute__((noreturn)) func(int x) { exit(x); }" },
  65         { "HAVE_ATTRIBUTE_PRINTF", DEFINES_FUNC, NULL,
  66           "static void __attribute__((format(__printf__, 1, 2))) func(const char *fmt, ...) { }" },
  67         { "HAVE_ATTRIBUTE_UNUSED", OUTSIDE_MAIN, NULL,
  68           "static int __attribute__((unused)) func(int x) { return x; }" },
  69         { "HAVE_ATTRIBUTE_USED", OUTSIDE_MAIN, NULL,
  70           "static int __attribute__((used)) func(int x) { return x; }" },
  71         { "HAVE_BIG_ENDIAN", INSIDE_MAIN|EXECUTE, NULL,
  72           "union { int i; char c[sizeof(int)]; } u;\n"
  73           "u.i = 0x01020304;\n"
  74           "return u.c[0] == 0x01 && u.c[1] == 0x02 && u.c[2] == 0x03 && u.c[3] == 0x04 ? 0 : 1;" },
  75         { "HAVE_BSWAP_64", DEFINES_FUNC, "HAVE_BYTESWAP_H",
  76           "#include <byteswap.h>\n"
  77           "static int func(int x) { return bswap_64(x); }" },
  78         { "HAVE_BUILTIN_CHOOSE_EXPR", INSIDE_MAIN, NULL,
  79           "return __builtin_choose_expr(1, 0, \"garbage\");" },
  80         { "HAVE_BUILTIN_CLZ", INSIDE_MAIN, NULL,
  81           "return __builtin_clz(1) == (sizeof(int)*8 - 1) ? 0 : 1;" },
  82         { "HAVE_BUILTIN_CLZL", INSIDE_MAIN, NULL,
  83           "return __builtin_clzl(1) == (sizeof(long)*8 - 1) ? 0 : 1;" },
  84         { "HAVE_BUILTIN_CLZLL", INSIDE_MAIN, NULL,
  85           "return __builtin_clzll(1) == (sizeof(long long)*8 - 1) ? 0 : 1;" },
  86         { "HAVE_BUILTIN_CONSTANT_P", INSIDE_MAIN, NULL,
  87           "return __builtin_constant_p(1) ? 0 : 1;" },
  88         { "HAVE_BUILTIN_EXPECT", INSIDE_MAIN, NULL,
  89           "return __builtin_expect(argc == 1, 1) ? 0 : 1;" },
  90         { "HAVE_BUILTIN_FFSL", INSIDE_MAIN, NULL,
  91           "return __builtin_ffsl(0L) == 0 ? 0 : 1;" },
  92         { "HAVE_BUILTIN_FFSLL", INSIDE_MAIN, NULL,
  93           "return __builtin_ffsll(0LL) == 0 ? 0 : 1;" },
  94         { "HAVE_BUILTIN_POPCOUNTL", INSIDE_MAIN, NULL,
  95           "return __builtin_popcountl(255L) == 8 ? 0 : 1;" },
  96         { "HAVE_BUILTIN_TYPES_COMPATIBLE_P", INSIDE_MAIN, NULL,
  97           "return __builtin_types_compatible_p(char *, int) ? 1 : 0;" },
  98         { "HAVE_BYTESWAP_H", OUTSIDE_MAIN, NULL,
  99           "#include <byteswap.h>\n" },
 100         { "HAVE_COMPOUND_LITERALS", INSIDE_MAIN, NULL,
 101           "int *foo = (int[]) { 1, 2, 3, 4 };\n"
 102           "return foo[0] ? 0 : 1;" },
 103         { "HAVE_FILE_OFFSET_BITS", DEFINES_EVERYTHING|EXECUTE,
 104           "HAVE_32BIT_OFF_T",
 105           "#define _FILE_OFFSET_BITS 64\n"
 106           "#include <sys/types.h>\n"
 107           "int main(int argc, char *argv[]) {\n"
 108           "     return sizeof(off_t) == 8 ? 0 : 1;\n"
 109           "}\n" },
 110         { "HAVE_FOR_LOOP_DECLARATION", INSIDE_MAIN, NULL,
 111           "for (int i = 0; i < argc; i++) { return 0; };\n"
 112           "return 1;" },
 113         { "HAVE_FLEXIBLE_ARRAY_MEMBER", OUTSIDE_MAIN, NULL,
 114           "struct foo { unsigned int x; int arr[]; };" },
 115         { "HAVE_GETPAGESIZE", DEFINES_FUNC, NULL,
 116           "#include <unistd.h>\n"
 117           "static int func(void) { return getpagesize(); }" },
 118         { "HAVE_ISBLANK", DEFINES_FUNC, NULL,
 119           "#include <ctype.h>\n"
 120           "static int func(void) { return isblank(' '); }" },
 121         { "HAVE_LITTLE_ENDIAN", INSIDE_MAIN|EXECUTE, NULL,
 122           "union { int i; char c[sizeof(int)]; } u;\n"
 123           "u.i = 0x01020304;\n"
 124           "return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;" },
 125         { "HAVE_MEMMEM", DEFINES_FUNC, NULL,
 126           "#define _GNU_SOURCE\n"
 127           "#include <string.h>\n"
 128           "static void *func(void *h, size_t hl, void *n, size_t nl) {\n"
 129           "return memmem(h, hl, n, nl);"
 130           "}\n", },
 131         { "HAVE_MMAP", DEFINES_FUNC, NULL,
 132           "#include <sys/mman.h>\n"
 133           "static void *func(int fd) {\n"
 134           "     return mmap(0, 65536, PROT_READ, MAP_SHARED, fd, 0);\n"
 135           "}" },
 136         { "HAVE_QSORT_R_PRIVATE_LAST",
 137           DEFINES_EVERYTHING|EXECUTE|MAY_NOT_COMPILE, NULL,
 138           "#define _GNU_SOURCE 1\n"
 139           "#include <stdlib.h>\n"
 140           "static int cmp(const void *lp, const void *rp, void *priv) {\n"
 141           " *(unsigned int *)priv = 1;\n"
 142           " return *(const int *)lp - *(const int *)rp; }\n"
 143           "int main(void) {\n"
 144           " int array[] = { 9, 2, 5 };\n"
 145           " unsigned int called = 0;\n"
 146           " qsort_r(array, 3, sizeof(int), cmp, &called);\n"
 147           " return called && array[0] == 2 && array[1] == 5 && array[2] == 9 ? 0 : 1;\n"
 148           "}\n" },
 149         { "HAVE_STACK_GROWS_UPWARDS", DEFINES_EVERYTHING|EXECUTE, NULL,
 150           "static long nest(const void *base, unsigned int i)\n"
 151           "{\n"
 152           "     if (i == 0)\n"
 153           "             return (const char *)&i - (const char *)base;\n"
 154           "     return nest(base, i-1);\n"
 155           "}\n"
 156           "int main(int argc, char *argv[]) {\n"
 157           "     return (nest(&argc, argc) > 0) ? 0 : 1\n;"
 158           "}\n" },
 159         { "HAVE_STATEMENT_EXPR", INSIDE_MAIN, NULL,
 160           "return ({ int x = argc; x == argc ? 0 : 1; });" },
 161         { "HAVE_TYPEOF", INSIDE_MAIN, NULL,
 162           "__typeof__(argc) i; i = argc; return i == argc ? 0 : 1;" },
 163         { "HAVE_UTIME", DEFINES_FUNC, NULL,
 164           "#include <sys/types.h>\n"
 165           "#include <utime.h>\n"
 166           "static int func(const char *filename) {\n"
 167           "     struct utimbuf times = { 0 };\n"
 168           "     return utime(filename, &times);\n"
 169           "}" },
 170         { "HAVE_WARN_UNUSED_RESULT", DEFINES_FUNC, NULL,
 171           "#include <sys/types.h>\n"
 172           "#include <utime.h>\n"
 173           "static __attribute__((warn_unused_result)) int func(int i) {\n"
 174           "     return i + 1;\n"
 175           "}" },
 176 };
 177
 178 static char *grab_fd(int fd)
 179 {
 180         int ret;
 181         size_t max, size = 0;
 182         char *buffer;
 183
 184         max = 16384;
 185         buffer = malloc(max+1);
 186         while ((ret = read(fd, buffer + size, max - size)) > 0) {
 187                 size += ret;
 188                 if (size == max)
 189                         buffer = realloc(buffer, max *= 2);
 190         }
 191         if (ret < 0)
 192                 err(1, "reading from command");
 193         buffer[size] = '\0';
 194         return buffer;
 195 }
 196
 197 static char *run(const char *cmd, int *exitstatus)
 198 {
 199         pid_t pid;
 200         int p[2];
 201         char *ret;
 202         int status;
 203
 204         if (pipe(p) != 0)
 205                 err(1, "creating pipe");
 206
 207         pid = fork();
 208         if (pid == -1)
 209                 err(1, "forking");
 210
 211         if (pid == 0) {
 212                 if (dup2(p[1], STDOUT_FILENO) != STDOUT_FILENO
 213                     || dup2(p[1], STDERR_FILENO) != STDERR_FILENO
 214                     || close(p[0]) != 0
 215                     || close(STDIN_FILENO) != 0
 216                     || open("/dev/null", O_RDONLY) != STDIN_FILENO)
 217                         exit(128);
 218
 219                 status = system(cmd);
 220                 if (WIFEXITED(status))
 221                         exit(WEXITSTATUS(status));
 222                 /* Here's a hint... */
 223                 exit(128 + WTERMSIG(status));
 224         }
 225
 226         close(p[1]);
 227         ret = grab_fd(p[0]);
 228         /* This shouldn't fail... */
 229         if (waitpid(pid, &status, 0) != pid)
 230                 err(1, "Failed to wait for child");
 231         close(p[0]);
 232         if (WIFEXITED(status))
 233                 *exitstatus = WEXITSTATUS(status);
 234         else
 235                 *exitstatus = -WTERMSIG(status);
 236         return ret;
 237 }
 238
 239 static char *connect_args(const char *argv[], const char *extra)
 240 {
 241         unsigned int i, len = strlen(extra) + 1;
 242         char *ret;
 243
 244         for (i = 1; argv[i]; i++)
 245                 len += 1 + strlen(argv[i]);
 246
 247         ret = malloc(len);
 248         len = 0;
 249         for (i = 1; argv[i]; i++) {
 250                 strcpy(ret + len, argv[i]);
 251                 len += strlen(argv[i]);
 252                 ret[len++] = ' ';
 253         }
 254         strcpy(ret + len, extra);
 255         return ret;
 256 }
 257
 258 static struct test *find_test(const char *name)
 259 {
 260         unsigned int i;
 261
 262         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
 263                 if (strcmp(tests[i].name, name) == 0)
 264                         return &tests[i];
 265         }
 266         abort();
 267 }
 268
 269 #define PRE_BOILERPLATE "/* Test program generated by configurator. */\n"
 270 #define MAIN_START_BOILERPLATE "int main(int argc, char *argv[]) {\n"
 271 #define USE_FUNC_BOILERPLATE "(void)func;\n"
 272 #define MAIN_BODY_BOILERPLATE "return 0;\n"
 273 #define MAIN_END_BOILERPLATE "}\n"
 274
 275 static bool run_test(const char *cmd, struct test *test)
 276 {
 277         char *output;
 278         FILE *outf;
 279         int status;
 280
 281         if (test->done)
 282                 return test->answer;
 283
 284         if (test->depends && !run_test(cmd, find_test(test->depends))) {
 285                 test->answer = false;
 286                 test->done = true;
 287                 return test->answer;
 288         }
 289
 290         outf = fopen(INPUT_FILE, "w");
 291         if (!outf)
 292                 err(1, "creating %s", INPUT_FILE);
 293
 294         fprintf(outf, "%s", PRE_BOILERPLATE);
 295         switch (test->style & ~(EXECUTE|MAY_NOT_COMPILE)) {
 296         case INSIDE_MAIN:
 297                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 298                 fprintf(outf, "%s", test->fragment);
 299                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 300                 break;
 301         case OUTSIDE_MAIN:
 302                 fprintf(outf, "%s", test->fragment);
 303                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 304                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 305                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 306                 break;
 307         case DEFINES_FUNC:
 308                 fprintf(outf, "%s", test->fragment);
 309                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 310                 fprintf(outf, "%s", USE_FUNC_BOILERPLATE);
 311                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 312                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 313                 break;
 314         case DEFINES_EVERYTHING:
 315                 fprintf(outf, "%s", test->fragment);
 316                 break;
 317         default:
 318                 abort();
 319
 320         }
 321         fclose(outf);
 322
 323         if (verbose > 1)
 324                 if (system("cat " INPUT_FILE) == -1);
 325
 326         output = run(cmd, &status);
 327         if (status != 0 || strstr(output, "warning")) {
 328                 if (verbose)
 329                         printf("Compile %s for %s, status %i: %s\n",
 330                                status ? "fail" : "warning",
 331                                test->name, status, output);
 332                 if ((test->style & EXECUTE) && !(test->style & MAY_NOT_COMPILE))
 333                         errx(1, "Test for %s did not compile:\n%s",
 334                              test->name, output);
 335                 test->answer = false;
 336                 free(output);
 337         } else {
 338                 /* Compile succeeded. */
 339                 free(output);
 340                 /* We run INSIDE_MAIN tests for sanity checking. */
 341                 if ((test->style & EXECUTE) || (test->style & INSIDE_MAIN)) {
 342                         output = run("./" OUTPUT_FILE, &status);
 343                         if (!(test->style & EXECUTE) && status != 0)
 344                                 errx(1, "Test for %s failed with %i:\n%s",
 345                                      test->name, status, output);
 346                         if (verbose && status)
 347                                 printf("%s exited %i\n", test->name, status);
 348                         free(output);
 349                 }
 350                 test->answer = (status == 0);
 351         }
 352         test->done = true;
 353         return test->answer;
 354 }
 355
 356 int main(int argc, const char *argv[])
 357 {
 358         char *cmd;
 359         unsigned int i;
 360         const char *default_args[]
 361                 = { "", DEFAULT_COMPILER, DEFAULT_FLAGS, NULL };
 362
 363         if (argc > 1) {
 364                 if (strcmp(argv[1], "--help") == 0) {
 365                         printf("Usage: configurator [-v] [<compiler> <flags>...]\n"
 366                                "  <compiler> <flags> will have \"-o <outfile> <infile.c>\" appended\n"
 367                                "Default: %s %s\n",
 368                                DEFAULT_COMPILER, DEFAULT_FLAGS);
 369                         exit(0);
 370                 }
 371                 if (strcmp(argv[1], "-v") == 0) {
 372                         argc--;
 373                         argv++;
 374                         verbose = 1;
 375                 } else if (strcmp(argv[1], "-vv") == 0) {
 376                         argc--;
 377                         argv++;
 378                         verbose = 2;
 379                 }
 380         }
 381
 382         if (argc == 1)
 383                 argv = default_args;
 384
 385         cmd = connect_args(argv, "-o " OUTPUT_FILE " " INPUT_FILE);
 386         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 387                 run_test(cmd, &tests[i]);
 388
 389         unlink(OUTPUT_FILE);
 390         unlink(INPUT_FILE);
 391
 392         cmd[strlen(cmd) - strlen(" -o " OUTPUT_FILE " " INPUT_FILE)] = '\0';
 393         printf("/* Generated by CCAN configurator */\n"
 394                "#ifndef CCAN_CONFIG_H\n"
 395                "#define CCAN_CONFIG_H\n");
 396         printf("#define _GNU_SOURCE /* Always use GNU extensions. */\n");
 397         printf("#define CCAN_COMPILER \"%s\"\n", argv[1]);
 398         printf("#define CCAN_CFLAGS \"%s\"\n\n", cmd + strlen(argv[1]) + 1);
 399         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 400                 printf("#define %s %u\n", tests[i].name, tests[i].answer);
 401         printf("#endif /* CCAN_CONFIG_H */\n");
 402         return 0;
 403 }