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           "#define _GNU_SOURCE\n"
 120           "#include <ctype.h>\n"
 121           "static int func(void) { return isblank(' '); }" },
 122         { "HAVE_LITTLE_ENDIAN", INSIDE_MAIN|EXECUTE, NULL,
 123           "union { int i; char c[sizeof(int)]; } u;\n"
 124           "u.i = 0x01020304;\n"
 125           "return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;" },
 126         { "HAVE_MEMMEM", DEFINES_FUNC, NULL,
 127           "#define _GNU_SOURCE\n"
 128           "#include <string.h>\n"
 129           "static void *func(void *h, size_t hl, void *n, size_t nl) {\n"
 130           "return memmem(h, hl, n, nl);"
 131           "}\n", },
 132         { "HAVE_MMAP", DEFINES_FUNC, NULL,
 133           "#include <sys/mman.h>\n"
 134           "static void *func(int fd) {\n"
 135           "     return mmap(0, 65536, PROT_READ, MAP_SHARED, fd, 0);\n"
 136           "}" },
 137         { "HAVE_QSORT_R_PRIVATE_LAST",
 138           DEFINES_EVERYTHING|EXECUTE|MAY_NOT_COMPILE, NULL,
 139           "#define _GNU_SOURCE 1\n"
 140           "#include <stdlib.h>\n"
 141           "static int cmp(const void *lp, const void *rp, void *priv) {\n"
 142           " *(unsigned int *)priv = 1;\n"
 143           " return *(const int *)lp - *(const int *)rp; }\n"
 144           "int main(void) {\n"
 145           " int array[] = { 9, 2, 5 };\n"
 146           " unsigned int called = 0;\n"
 147           " qsort_r(array, 3, sizeof(int), cmp, &called);\n"
 148           " return called && array[0] == 2 && array[1] == 5 && array[2] == 9 ? 0 : 1;\n"
 149           "}\n" },
 150         { "HAVE_STACK_GROWS_UPWARDS", DEFINES_EVERYTHING|EXECUTE, NULL,
 151           "static long nest(const void *base, unsigned int i)\n"
 152           "{\n"
 153           "     if (i == 0)\n"
 154           "             return (const char *)&i - (const char *)base;\n"
 155           "     return nest(base, i-1);\n"
 156           "}\n"
 157           "int main(int argc, char *argv[]) {\n"
 158           "     return (nest(&argc, argc) > 0) ? 0 : 1\n;"
 159           "}\n" },
 160         { "HAVE_STATEMENT_EXPR", INSIDE_MAIN, NULL,
 161           "return ({ int x = argc; x == argc ? 0 : 1; });" },
 162         { "HAVE_TYPEOF", INSIDE_MAIN, NULL,
 163           "__typeof__(argc) i; i = argc; return i == argc ? 0 : 1;" },
 164         { "HAVE_UTIME", DEFINES_FUNC, NULL,
 165           "#include <sys/types.h>\n"
 166           "#include <utime.h>\n"
 167           "static int func(const char *filename) {\n"
 168           "     struct utimbuf times = { 0 };\n"
 169           "     return utime(filename, &times);\n"
 170           "}" },
 171         { "HAVE_WARN_UNUSED_RESULT", DEFINES_FUNC, NULL,
 172           "#include <sys/types.h>\n"
 173           "#include <utime.h>\n"
 174           "static __attribute__((warn_unused_result)) int func(int i) {\n"
 175           "     return i + 1;\n"
 176           "}" },
 177 };
 178
 179 static char *grab_fd(int fd)
 180 {
 181         int ret;
 182         size_t max, size = 0;
 183         char *buffer;
 184
 185         max = 16384;
 186         buffer = malloc(max+1);
 187         while ((ret = read(fd, buffer + size, max - size)) > 0) {
 188                 size += ret;
 189                 if (size == max)
 190                         buffer = realloc(buffer, max *= 2);
 191         }
 192         if (ret < 0)
 193                 err(1, "reading from command");
 194         buffer[size] = '\0';
 195         return buffer;
 196 }
 197
 198 static char *run(const char *cmd, int *exitstatus)
 199 {
 200         pid_t pid;
 201         int p[2];
 202         char *ret;
 203         int status;
 204
 205         if (pipe(p) != 0)
 206                 err(1, "creating pipe");
 207
 208         pid = fork();
 209         if (pid == -1)
 210                 err(1, "forking");
 211
 212         if (pid == 0) {
 213                 if (dup2(p[1], STDOUT_FILENO) != STDOUT_FILENO
 214                     || dup2(p[1], STDERR_FILENO) != STDERR_FILENO
 215                     || close(p[0]) != 0
 216                     || close(STDIN_FILENO) != 0
 217                     || open("/dev/null", O_RDONLY) != STDIN_FILENO)
 218                         exit(128);
 219
 220                 status = system(cmd);
 221                 if (WIFEXITED(status))
 222                         exit(WEXITSTATUS(status));
 223                 /* Here's a hint... */
 224                 exit(128 + WTERMSIG(status));
 225         }
 226
 227         close(p[1]);
 228         ret = grab_fd(p[0]);
 229         /* This shouldn't fail... */
 230         if (waitpid(pid, &status, 0) != pid)
 231                 err(1, "Failed to wait for child");
 232         close(p[0]);
 233         if (WIFEXITED(status))
 234                 *exitstatus = WEXITSTATUS(status);
 235         else
 236                 *exitstatus = -WTERMSIG(status);
 237         return ret;
 238 }
 239
 240 static char *connect_args(const char *argv[], const char *extra)
 241 {
 242         unsigned int i, len = strlen(extra) + 1;
 243         char *ret;
 244
 245         for (i = 1; argv[i]; i++)
 246                 len += 1 + strlen(argv[i]);
 247
 248         ret = malloc(len);
 249         len = 0;
 250         for (i = 1; argv[i]; i++) {
 251                 strcpy(ret + len, argv[i]);
 252                 len += strlen(argv[i]);
 253                 ret[len++] = ' ';
 254         }
 255         strcpy(ret + len, extra);
 256         return ret;
 257 }
 258
 259 static struct test *find_test(const char *name)
 260 {
 261         unsigned int i;
 262
 263         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
 264                 if (strcmp(tests[i].name, name) == 0)
 265                         return &tests[i];
 266         }
 267         abort();
 268 }
 269
 270 #define PRE_BOILERPLATE "/* Test program generated by configurator. */\n"
 271 #define MAIN_START_BOILERPLATE "int main(int argc, char *argv[]) {\n"
 272 #define USE_FUNC_BOILERPLATE "(void)func;\n"
 273 #define MAIN_BODY_BOILERPLATE "return 0;\n"
 274 #define MAIN_END_BOILERPLATE "}\n"
 275
 276 static bool run_test(const char *cmd, struct test *test)
 277 {
 278         char *output;
 279         FILE *outf;
 280         int status;
 281
 282         if (test->done)
 283                 return test->answer;
 284
 285         if (test->depends && !run_test(cmd, find_test(test->depends))) {
 286                 test->answer = false;
 287                 test->done = true;
 288                 return test->answer;
 289         }
 290
 291         outf = fopen(INPUT_FILE, "w");
 292         if (!outf)
 293                 err(1, "creating %s", INPUT_FILE);
 294
 295         fprintf(outf, "%s", PRE_BOILERPLATE);
 296         switch (test->style & ~(EXECUTE|MAY_NOT_COMPILE)) {
 297         case INSIDE_MAIN:
 298                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 299                 fprintf(outf, "%s", test->fragment);
 300                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 301                 break;
 302         case OUTSIDE_MAIN:
 303                 fprintf(outf, "%s", test->fragment);
 304                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 305                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 306                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 307                 break;
 308         case DEFINES_FUNC:
 309                 fprintf(outf, "%s", test->fragment);
 310                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 311                 fprintf(outf, "%s", USE_FUNC_BOILERPLATE);
 312                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 313                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 314                 break;
 315         case DEFINES_EVERYTHING:
 316                 fprintf(outf, "%s", test->fragment);
 317                 break;
 318         default:
 319                 abort();
 320
 321         }
 322         fclose(outf);
 323
 324         if (verbose > 1)
 325                 if (system("cat " INPUT_FILE) == -1);
 326
 327         output = run(cmd, &status);
 328         if (status != 0 || strstr(output, "warning")) {
 329                 if (verbose)
 330                         printf("Compile %s for %s, status %i: %s\n",
 331                                status ? "fail" : "warning",
 332                                test->name, status, output);
 333                 if ((test->style & EXECUTE) && !(test->style & MAY_NOT_COMPILE))
 334                         errx(1, "Test for %s did not compile:\n%s",
 335                              test->name, output);
 336                 test->answer = false;
 337                 free(output);
 338         } else {
 339                 /* Compile succeeded. */
 340                 free(output);
 341                 /* We run INSIDE_MAIN tests for sanity checking. */
 342                 if ((test->style & EXECUTE) || (test->style & INSIDE_MAIN)) {
 343                         output = run("./" OUTPUT_FILE, &status);
 344                         if (!(test->style & EXECUTE) && status != 0)
 345                                 errx(1, "Test for %s failed with %i:\n%s",
 346                                      test->name, status, output);
 347                         if (verbose && status)
 348                                 printf("%s exited %i\n", test->name, status);
 349                         free(output);
 350                 }
 351                 test->answer = (status == 0);
 352         }
 353         test->done = true;
 354         return test->answer;
 355 }
 356
 357 int main(int argc, const char *argv[])
 358 {
 359         char *cmd;
 360         unsigned int i;
 361         const char *default_args[]
 362                 = { "", DEFAULT_COMPILER, DEFAULT_FLAGS, NULL };
 363
 364         if (argc > 1) {
 365                 if (strcmp(argv[1], "--help") == 0) {
 366                         printf("Usage: configurator [-v] [<compiler> <flags>...]\n"
 367                                "  <compiler> <flags> will have \"-o <outfile> <infile.c>\" appended\n"
 368                                "Default: %s %s\n",
 369                                DEFAULT_COMPILER, DEFAULT_FLAGS);
 370                         exit(0);
 371                 }
 372                 if (strcmp(argv[1], "-v") == 0) {
 373                         argc--;
 374                         argv++;
 375                         verbose = 1;
 376                 } else if (strcmp(argv[1], "-vv") == 0) {
 377                         argc--;
 378                         argv++;
 379                         verbose = 2;
 380                 }
 381         }
 382
 383         if (argc == 1)
 384                 argv = default_args;
 385
 386         cmd = connect_args(argv, "-o " OUTPUT_FILE " " INPUT_FILE);
 387         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 388                 run_test(cmd, &tests[i]);
 389
 390         unlink(OUTPUT_FILE);
 391         unlink(INPUT_FILE);
 392
 393         cmd[strlen(cmd) - strlen(" -o " OUTPUT_FILE " " INPUT_FILE)] = '\0';
 394         printf("/* Generated by CCAN configurator */\n"
 395                "#ifndef CCAN_CONFIG_H\n"
 396                "#define CCAN_CONFIG_H\n");
 397         printf("#ifndef _GNU_SOURCE\n");
 398         printf("#define _GNU_SOURCE /* Always use GNU extensions. */\n");
 399         printf("#endif\n");
 400         printf("#define CCAN_COMPILER \"%s\"\n", argv[1]);
 401         printf("#define CCAN_CFLAGS \"%s\"\n\n", cmd + strlen(argv[1]) + 1);
 402         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 403                 printf("#define %s %u\n", tests[i].name, tests[i].answer);
 404         printf("#endif /* CCAN_CONFIG_H */\n");
 405         return 0;
 406 }