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         EXECUTE                 = 0x8000
  28 };
  29
  30 struct test {
  31         const char *name;
  32         enum test_style style;
  33         const char *depends;
  34         const char *fragment;
  35         bool done;
  36         bool answer;
  37 };
  38
  39 static struct test tests[] = {
  40         { "HAVE_ALIGNOF", INSIDE_MAIN, NULL,
  41           "return __alignof__(double) > 0 ? 0 : 1;" },
  42         { "HAVE_ASPRINTF", DEFINES_FUNC, NULL,
  43           "#define _GNU_SOURCE\n"
  44           "#include <stdio.h>\n"
  45           "static char *func(int x) {"
  46           "     char *p;\n"
  47           "     if (asprintf(&p, \"%u\", x) == -1) p = NULL;"
  48           "     return p;\n"
  49           "}" },
  50         { "HAVE_ATTRIBUTE_COLD", DEFINES_FUNC, NULL,
  51           "static int __attribute__((cold)) func(int x) { return x; }" },
  52         { "HAVE_ATTRIBUTE_CONST", DEFINES_FUNC, NULL,
  53           "static int __attribute__((const)) func(int x) { return x; }" },
  54         { "HAVE_ATTRIBUTE_MAY_ALIAS", OUTSIDE_MAIN, NULL,
  55           "typedef short __attribute__((__may_alias__)) short_a;" },
  56         { "HAVE_ATTRIBUTE_NORETURN", DEFINES_FUNC, NULL,
  57           "#include <stdlib.h>\n"
  58           "static void __attribute__((noreturn)) func(int x) { exit(x); }" },
  59         { "HAVE_ATTRIBUTE_PRINTF", DEFINES_FUNC, NULL,
  60           "static void __attribute__((format(__printf__, 1, 2))) func(const char *fmt, ...) { }" },
  61         { "HAVE_ATTRIBUTE_UNUSED", OUTSIDE_MAIN, NULL,
  62           "static int __attribute__((unused)) func(int x) { return x; }" },
  63         { "HAVE_ATTRIBUTE_USED", OUTSIDE_MAIN, NULL,
  64           "static int __attribute__((used)) func(int x) { return x; }" },
  65         { "HAVE_BIG_ENDIAN", INSIDE_MAIN|EXECUTE, NULL,
  66           "union { int i; char c[sizeof(int)]; } u;\n"
  67           "u.i = 0x01020304;\n"
  68           "return u.c[0] == 0x01 && u.c[1] == 0x02 && u.c[2] == 0x03 && u.c[3] == 0x04 ? 0 : 1;" },
  69         { "HAVE_BSWAP_64", DEFINES_FUNC, "HAVE_BYTESWAP_H",
  70           "#include <byteswap.h>\n"
  71           "static int func(int x) { return bswap_64(x); }" },
  72         { "HAVE_BUILTIN_CHOOSE_EXPR", INSIDE_MAIN, NULL,
  73           "return __builtin_choose_expr(1, 0, \"garbage\");" },
  74         { "HAVE_BUILTIN_CLZ", INSIDE_MAIN, NULL,
  75           "return __builtin_clz(1) == (sizeof(int)*8 - 1) ? 0 : 1;" },
  76         { "HAVE_BUILTIN_CLZL", INSIDE_MAIN, NULL,
  77           "return __builtin_clzl(1) == (sizeof(long)*8 - 1) ? 0 : 1;" },
  78         { "HAVE_BUILTIN_CLZLL", INSIDE_MAIN, NULL,
  79           "return __builtin_clzll(1) == (sizeof(long long)*8 - 1) ? 0 : 1;" },
  80         { "HAVE_BUILTIN_CONSTANT_P", INSIDE_MAIN, NULL,
  81           "return __builtin_constant_p(1) ? 0 : 1;" },
  82         { "HAVE_BUILTIN_EXPECT", INSIDE_MAIN, NULL,
  83           "return __builtin_expect(argc == 1, 1) ? 0 : 1;" },
  84         { "HAVE_BUILTIN_FFSL", INSIDE_MAIN, NULL,
  85           "return __builtin_ffsl(0L) == 0 ? 0 : 1;" },
  86         { "HAVE_BUILTIN_FFSLL", INSIDE_MAIN, NULL,
  87           "return __builtin_ffsll(0LL) == 0 ? 0 : 1;" },
  88         { "HAVE_BUILTIN_POPCOUNTL", INSIDE_MAIN, NULL,
  89           "return __builtin_popcountl(255L) == 8 ? 0 : 1;" },
  90         { "HAVE_BUILTIN_TYPES_COMPATIBLE_P", INSIDE_MAIN, NULL,
  91           "return __builtin_types_compatible_p(char *, int) ? 1 : 0;" },
  92         { "HAVE_BYTESWAP_H", OUTSIDE_MAIN, NULL,
  93           "#include <byteswap.h>\n" },
  94         { "HAVE_COMPOUND_LITERALS", INSIDE_MAIN, NULL,
  95           "int *foo = (int[]) { 1, 2, 3, 4 };\n"
  96           "return foo[0] ? 0 : 1;" },
  97         { "HAVE_FOR_LOOP_DECLARATION", INSIDE_MAIN, NULL,
  98           "for (int i = 0; i < argc; i++) { return 0; };\n"
  99           "return 1;" },
 100         { "HAVE_FLEXIBLE_ARRAY_MEMBER", OUTSIDE_MAIN, NULL,
 101           "struct foo { unsigned int x; int arr[]; };" },
 102         { "HAVE_GETPAGESIZE", DEFINES_FUNC, NULL,
 103           "#include <unistd.h>\n"
 104           "static int func(void) { return getpagesize(); }" },
 105         { "HAVE_LITTLE_ENDIAN", INSIDE_MAIN|EXECUTE, NULL,
 106           "union { int i; char c[sizeof(int)]; } u;\n"
 107           "u.i = 0x01020304;\n"
 108           "return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;" },
 109         { "HAVE_MEMMEM", DEFINES_FUNC, NULL,
 110           "#define _GNU_SOURCE\n"
 111           "#include <string.h>\n"
 112           "static void *func(void *h, size_t hl, void *n, size_t nl) {\n"
 113           "return memmem(h, hl, n, nl);"
 114           "}\n", },
 115         { "HAVE_MMAP", DEFINES_FUNC, NULL,
 116           "#include <sys/mman.h>\n"
 117           "static void *func(int fd) {\n"
 118           "     return mmap(0, 65536, PROT_READ, MAP_SHARED, fd, 0);\n"
 119           "}" },
 120         { "HAVE_NESTED_FUNCTIONS", DEFINES_FUNC, NULL,
 121           "void (*func(int val))(int);\n"
 122           "void (*func(int val))(int) {\n"
 123           "     auto void add(int val2);\n"
 124           "     void add(int val2) { val += val2; }\n"
 125           "     return add;\n"
 126           "}\n" },
 127         { "HAVE_STACK_GROWS_UPWARDS", DEFINES_EVERYTHING|EXECUTE, NULL,
 128           "static long nest(const void *base, unsigned int i)\n"
 129           "{\n"
 130           "     if (i == 0)\n"
 131           "             return (const char *)&i - (const char *)base;\n"
 132           "     return nest(base, i-1);\n"
 133           "}\n"
 134           "int main(int argc, char *argv[]) {\n"
 135           "     return (nest(&argc, argc) > 0) ? 0 : 1\n;"
 136           "}\n" },
 137         { "HAVE_STATEMENT_EXPR", INSIDE_MAIN, NULL,
 138           "return ({ int x = argc; x == argc ? 0 : 1; });" },
 139         { "HAVE_TYPEOF", INSIDE_MAIN, NULL,
 140           "__typeof__(argc) i; i = argc; return i == argc ? 0 : 1;" },
 141         { "HAVE_UTIME", DEFINES_FUNC, NULL,
 142           "#include <sys/types.h>\n"
 143           "#include <utime.h>\n"
 144           "static int func(const char *filename) {\n"
 145           "     struct utimbuf times = { 0 };\n"
 146           "     return utime(filename, &times);\n"
 147           "}" },
 148         { "HAVE_WARN_UNUSED_RESULT", DEFINES_FUNC, NULL,
 149           "#include <sys/types.h>\n"
 150           "#include <utime.h>\n"
 151           "static __attribute__((warn_unused_result)) int func(int i) {\n"
 152           "     return i + 1;\n"
 153           "}" },
 154 };
 155
 156 static char *grab_fd(int fd)
 157 {
 158         int ret;
 159         size_t max, size = 0;
 160         char *buffer;
 161
 162         max = 16384;
 163         buffer = malloc(max+1);
 164         while ((ret = read(fd, buffer + size, max - size)) > 0) {
 165                 size += ret;
 166                 if (size == max)
 167                         buffer = realloc(buffer, max *= 2);
 168         }
 169         if (ret < 0)
 170                 err(1, "reading from command");
 171         buffer[size] = '\0';
 172         return buffer;
 173 }
 174
 175 static char *run(const char *cmd, int *exitstatus)
 176 {
 177         pid_t pid;
 178         int p[2];
 179         char *ret;
 180         int status;
 181
 182         if (pipe(p) != 0)
 183                 err(1, "creating pipe");
 184
 185         pid = fork();
 186         if (pid == -1)
 187                 err(1, "forking");
 188
 189         if (pid == 0) {
 190                 if (dup2(p[1], STDOUT_FILENO) != STDOUT_FILENO
 191                     || dup2(p[1], STDERR_FILENO) != STDERR_FILENO
 192                     || close(p[0]) != 0
 193                     || close(STDIN_FILENO) != 0
 194                     || open("/dev/null", O_RDONLY) != STDIN_FILENO)
 195                         exit(128);
 196
 197                 status = system(cmd);
 198                 if (WIFEXITED(status))
 199                         exit(WEXITSTATUS(status));
 200                 /* Here's a hint... */
 201                 exit(128 + WTERMSIG(status));
 202         }
 203
 204         close(p[1]);
 205         ret = grab_fd(p[0]);
 206         /* This shouldn't fail... */
 207         if (waitpid(pid, &status, 0) != pid)
 208                 err(1, "Failed to wait for child");
 209         close(p[0]);
 210         if (WIFEXITED(status))
 211                 *exitstatus = WEXITSTATUS(status);
 212         else
 213                 *exitstatus = -WTERMSIG(status);
 214         return ret;
 215 }
 216
 217 static char *connect_args(const char *argv[], const char *extra)
 218 {
 219         unsigned int i, len = strlen(extra) + 1;
 220         char *ret;
 221
 222         for (i = 1; argv[i]; i++)
 223                 len += 1 + strlen(argv[i]);
 224
 225         ret = malloc(len);
 226         len = 0;
 227         for (i = 1; argv[i]; i++) {
 228                 strcpy(ret + len, argv[i]);
 229                 len += strlen(argv[i]);
 230                 ret[len++] = ' ';
 231         }
 232         strcpy(ret + len, extra);
 233         return ret;
 234 }
 235
 236 static struct test *find_test(const char *name)
 237 {
 238         unsigned int i;
 239
 240         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
 241                 if (strcmp(tests[i].name, name) == 0)
 242                         return &tests[i];
 243         }
 244         abort();
 245 }
 246
 247 #define PRE_BOILERPLATE "/* Test program generated by configurator. */\n"
 248 #define MAIN_START_BOILERPLATE "int main(int argc, char *argv[]) {\n"
 249 #define USE_FUNC_BOILERPLATE "(void)func;\n"
 250 #define MAIN_BODY_BOILERPLATE "return 0;\n"
 251 #define MAIN_END_BOILERPLATE "}\n"
 252
 253 static bool run_test(const char *cmd, struct test *test)
 254 {
 255         char *output;
 256         FILE *outf;
 257         int status;
 258
 259         if (test->done)
 260                 return test->answer;
 261
 262         if (test->depends && !run_test(cmd, find_test(test->depends))) {
 263                 test->answer = false;
 264                 test->done = true;
 265                 return test->answer;
 266         }
 267
 268         outf = fopen(INPUT_FILE, "w");
 269         if (!outf)
 270                 err(1, "creating %s", INPUT_FILE);
 271
 272         fprintf(outf, "%s", PRE_BOILERPLATE);
 273         switch (test->style & ~EXECUTE) {
 274         case INSIDE_MAIN:
 275                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 276                 fprintf(outf, "%s", test->fragment);
 277                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 278                 break;
 279         case OUTSIDE_MAIN:
 280                 fprintf(outf, "%s", test->fragment);
 281                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 282                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 283                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 284                 break;
 285         case DEFINES_FUNC:
 286                 fprintf(outf, "%s", test->fragment);
 287                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 288                 fprintf(outf, "%s", USE_FUNC_BOILERPLATE);
 289                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 290                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 291                 break;
 292         case DEFINES_EVERYTHING:
 293                 fprintf(outf, "%s", test->fragment);
 294                 break;
 295         default:
 296                 abort();
 297
 298         }
 299         fclose(outf);
 300
 301         if (verbose > 1)
 302                 if (system("cat " INPUT_FILE) == -1);
 303
 304         output = run(cmd, &status);
 305         if (status != 0 || strstr(output, "warning")) {
 306                 if (verbose)
 307                         printf("Compile %s for %s, status %i: %s\n",
 308                                status ? "fail" : "warning",
 309                                test->name, status, output);
 310                 if (test->style & EXECUTE)
 311                         errx(1, "Test for %s did not compile:\n%s",
 312                              test->name, output);
 313                 test->answer = false;
 314                 free(output);
 315         } else {
 316                 /* Compile succeeded. */
 317                 free(output);
 318                 /* We run INSIDE_MAIN tests for sanity checking. */
 319                 if ((test->style & EXECUTE) || (test->style & INSIDE_MAIN)) {
 320                         output = run("./" OUTPUT_FILE, &status);
 321                         if (!(test->style & EXECUTE) && status != 0)
 322                                 errx(1, "Test for %s failed with %i:\n%s",
 323                                      test->name, status, output);
 324                         if (verbose && status)
 325                                 printf("%s exited %i\n", test->name, status);
 326                         free(output);
 327                 }
 328                 test->answer = (status == 0);
 329         }
 330         test->done = true;
 331         return test->answer;
 332 }
 333
 334 int main(int argc, const char *argv[])
 335 {
 336         char *cmd;
 337         unsigned int i;
 338         const char *default_args[]
 339                 = { "", DEFAULT_COMPILER, DEFAULT_FLAGS, NULL };
 340
 341         if (argc > 1) {
 342                 if (strcmp(argv[1], "--help") == 0) {
 343                         printf("Usage: configurator [-v] [<compiler> <flags>...]\n"
 344                                "  <compiler> <flags> will have \"-o <outfile> <infile.c>\" appended\n"
 345                                "Default: %s %s\n",
 346                                DEFAULT_COMPILER, DEFAULT_FLAGS);
 347                         exit(0);
 348                 }
 349                 if (strcmp(argv[1], "-v") == 0) {
 350                         argc--;
 351                         argv++;
 352                         verbose = 1;
 353                 } else if (strcmp(argv[1], "-vv") == 0) {
 354                         argc--;
 355                         argv++;
 356                         verbose = 2;
 357                 }
 358         }
 359
 360         if (argc == 1)
 361                 argv = default_args;
 362
 363         cmd = connect_args(argv, "-o " OUTPUT_FILE " " INPUT_FILE);
 364         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 365                 run_test(cmd, &tests[i]);
 366
 367         unlink(OUTPUT_FILE);
 368         unlink(INPUT_FILE);
 369
 370         cmd[strlen(cmd) - strlen(" -o " OUTPUT_FILE " " INPUT_FILE)] = '\0';
 371         printf("/* Generated by CCAN configurator */\n"
 372                "#ifndef CCAN_CONFIG_H\n"
 373                "#define CCAN_CONFIG_H\n");
 374         printf("#define _GNU_SOURCE /* Always use GNU extensions. */\n");
 375         printf("#define CCAN_COMPILER \"%s\"\n", argv[1]);
 376         printf("#define CCAN_CFLAGS \"%s\"\n\n", cmd + strlen(argv[1]) + 1);
 377         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 378                 printf("#define %s %u\n", tests[i].name, tests[i].answer);
 379         printf("#endif /* CCAN_CONFIG_H */\n");
 380         return 0;
 381 }