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