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 -Werror"
  16
  17 #define OUTPUT_FILE "configurator.out"
  18 #define INPUT_FILE "configuratortest.c"
  19
  20 static int verbose;
  21
  22 enum test_style {
  23         EXECUTE,
  24         OUTSIDE_MAIN,
  25         DEFINES_FUNC,
  26         INSIDE_MAIN
  27 };
  28
  29 struct test {
  30         const char *name;
  31         enum test_style style;
  32         const char *depends;
  33         const char *fragment;
  34         bool done;
  35         bool answer;
  36 };
  37
  38 static struct test tests[] = {
  39         { "HAVE_ALIGNOF", INSIDE_MAIN, NULL,
  40           "return __alignof__(double) > 0 ? 0 : 1;" },
  41         { "HAVE_ATTRIBUTE_COLD", DEFINES_FUNC, NULL,
  42           "static int __attribute__((cold)) func(int x) { return x; }" },
  43         { "HAVE_ATTRIBUTE_CONST", DEFINES_FUNC, NULL,
  44           "static int __attribute__((const)) func(int x) { return x; }" },
  45         { "HAVE_ATTRIBUTE_MAY_ALIAS", OUTSIDE_MAIN, NULL,
  46           "typedef short __attribute__((__may_alias__)) short_a;" },
  47         { "HAVE_ATTRIBUTE_PRINTF", DEFINES_FUNC, NULL,
  48           "static void __attribute__((format(__printf__, 1, 2))) func(const char *fmt, ...) { }" },
  49         { "HAVE_ATTRIBUTE_UNUSED", OUTSIDE_MAIN, NULL,
  50           "static int __attribute__((unused)) func(int x) { return x; }" },
  51         { "HAVE_ATTRIBUTE_USED", OUTSIDE_MAIN, NULL,
  52           "static int __attribute__((used)) func(int x) { return x; }" },
  53         { "HAVE_BIG_ENDIAN", EXECUTE, NULL,
  54           "union { int i; char c[sizeof(int)]; } u;\n"
  55           "u.i = 0x01020304;\n"
  56           "return u.c[0] == 0x01 && u.c[1] == 0x02 && u.c[2] == 0x03 && u.c[3] == 0x04 ? 0 : 1;" },
  57         { "HAVE_BSWAP_64", DEFINES_FUNC, "HAVE_BYTESWAP_H",
  58           "#include <byteswap.h>\n"
  59           "static int func(int x) { return bswap_64(x); }" },
  60         { "HAVE_BUILTIN_CHOOSE_EXPR", INSIDE_MAIN, NULL,
  61           "return __builtin_choose_expr(1, 0, \"garbage\");" },
  62         { "HAVE_BUILTIN_CLZ", INSIDE_MAIN, NULL,
  63           "return __builtin_clz(1) == (sizeof(int)*8 - 1) ? 0 : 1;" },
  64         { "HAVE_BUILTIN_CLZL", INSIDE_MAIN, NULL,
  65           "return __builtin_clzl(1) == (sizeof(long)*8 - 1) ? 0 : 1;" },
  66         { "HAVE_BUILTIN_CLZLL", INSIDE_MAIN, NULL,
  67           "return __builtin_clzll(1) == (sizeof(long long)*8 - 1) ? 0 : 1;" },
  68         { "HAVE_BUILTIN_CONSTANT_P", INSIDE_MAIN, NULL,
  69           "return __builtin_constant_p(1) ? 0 : 1;" },
  70         { "HAVE_BUILTIN_EXPECT", INSIDE_MAIN, NULL,
  71           "return __builtin_expect(argc == 1, 1) ? 0 : 1;" },
  72         { "HAVE_BUILTIN_FFSL", INSIDE_MAIN, NULL,
  73           "return __builtin_ffsl(0L) == 0 ? 0 : 1;" },
  74         { "HAVE_BUILTIN_POPCOUNTL", INSIDE_MAIN, NULL,
  75           "return __builtin_popcountl(255L) == 8 ? 0 : 1;" },
  76         { "HAVE_BUILTIN_TYPES_COMPATIBLE_P", INSIDE_MAIN, NULL,
  77           "return __builtin_types_compatible_p(char *, int) ? 1 : 0;" },
  78         { "HAVE_BYTESWAP_H", OUTSIDE_MAIN, NULL,
  79           "#include <byteswap.h>\n" },
  80         { "HAVE_COMPOUND_LITERALS", INSIDE_MAIN, NULL,
  81           "char **foo = (char *[]) { \"x\", \"y\", \"z\" };\n"
  82           "return foo[0] ? 0 : 1;" },
  83         { "HAVE_FOR_LOOP_DECLARATION", INSIDE_MAIN, NULL,
  84           "for (int i = 0; i < argc; i++) { return 0; };\n"
  85           "return 1;" },
  86         { "HAVE_GETPAGESIZE", DEFINES_FUNC, NULL,
  87           "#include <unistd.h>\n"
  88           "static int func(void) { return getpagesize(); }" },
  89         { "HAVE_LITTLE_ENDIAN", EXECUTE, NULL,
  90           "union { int i; char c[sizeof(int)]; } u;\n"
  91           "u.i = 0x01020304;\n"
  92           "return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;" },
  93         { "HAVE_MMAP", DEFINES_FUNC, NULL,
  94           "#include <sys/mman.h>\n"
  95           "static void *func(int fd) {\n"
  96           "     return mmap(0, 65536, PROT_READ, MAP_SHARED, fd, 0);\n"
  97           "}" },
  98         { "HAVE_NESTED_FUNCTIONS", DEFINES_FUNC, NULL,
  99           "static int func(int val) {\n"
 100           "     auto void add(int val2);\n"
 101           "     void add(int val2) { val += val2; }\n"
 102           "     add(7);\n"
 103           "     return val;\n"
 104           "}" },
 105         { "HAVE_STATEMENT_EXPR", INSIDE_MAIN, NULL,
 106           "return ({ int x = argc; x == argc ? 0 : 1; });" },
 107         { "HAVE_TYPEOF", INSIDE_MAIN, NULL,
 108           "__typeof__(argc) i; i = argc; return i == argc ? 0 : 1;" },
 109         { "HAVE_UTIME", DEFINES_FUNC, NULL,
 110           "#include <sys/types.h>\n"
 111           "#include <utime.h>\n"
 112           "static int func(const char *filename) {\n"
 113           "     struct utimbuf times = { 0 };\n"
 114           "     return utime(filename, &times);\n"
 115           "}" },
 116         { "HAVE_WARN_UNUSED_RESULT", DEFINES_FUNC, NULL,
 117           "#include <sys/types.h>\n"
 118           "#include <utime.h>\n"
 119           "static __attribute__((warn_unused_result)) int func(int i) {\n"
 120           "     return i + 1;\n"
 121           "}" },
 122 };
 123
 124 static char *grab_fd(int fd)
 125 {
 126         int ret;
 127         size_t max, size = 0;
 128         char *buffer;
 129
 130         max = 16384;
 131         buffer = malloc(max+1);
 132         while ((ret = read(fd, buffer + size, max - size)) > 0) {
 133                 size += ret;
 134                 if (size == max)
 135                         buffer = realloc(buffer, max *= 2);
 136         }
 137         if (ret < 0)
 138                 err(1, "reading from command");
 139         buffer[size] = '\0';
 140         return buffer;
 141 }
 142
 143 static char *run(const char *cmd, int *exitstatus)
 144 {
 145         pid_t pid;
 146         int p[2];
 147         char *ret;
 148         int status;
 149
 150         if (pipe(p) != 0)
 151                 err(1, "creating pipe");
 152
 153         pid = fork();
 154         if (pid == -1)
 155                 err(1, "forking");
 156
 157         if (pid == 0) {
 158                 if (dup2(p[1], STDOUT_FILENO) != STDOUT_FILENO
 159                     || dup2(p[1], STDERR_FILENO) != STDERR_FILENO
 160                     || close(p[0]) != 0
 161                     || close(STDIN_FILENO) != 0
 162                     || open("/dev/null", O_RDONLY) != STDIN_FILENO)
 163                         exit(128);
 164
 165                 status = system(cmd);
 166                 if (WIFEXITED(status))
 167                         exit(WEXITSTATUS(status));
 168                 /* Here's a hint... */
 169                 exit(128 + WTERMSIG(status));
 170         }
 171
 172         close(p[1]);
 173         ret = grab_fd(p[0]);
 174         /* This shouldn't fail... */
 175         if (waitpid(pid, &status, 0) != pid)
 176                 err(1, "Failed to wait for child");
 177         close(p[0]);
 178         if (WIFEXITED(status))
 179                 *exitstatus = WEXITSTATUS(status);
 180         else
 181                 *exitstatus = -WTERMSIG(status);
 182         return ret;
 183 }
 184
 185 static char *connect_args(char *argv[], const char *extra)
 186 {
 187         unsigned int i, len = strlen(extra) + 1;
 188         char *ret;
 189
 190         for (i = 1; argv[i]; i++)
 191                 len += 1 + strlen(argv[i]);
 192
 193         ret = malloc(len);
 194         len = 0;
 195         for (i = 1; argv[i]; i++) {
 196                 strcpy(ret + len, argv[i]);
 197                 len += strlen(argv[i]);
 198                 ret[len++] = ' ';
 199         }
 200         strcpy(ret + len, extra);
 201         return ret;
 202 }
 203
 204 static struct test *find_test(const char *name)
 205 {
 206         unsigned int i;
 207
 208         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
 209                 if (strcmp(tests[i].name, name) == 0)
 210                         return &tests[i];
 211         }
 212         abort();
 213 }
 214
 215 #define PRE_BOILERPLATE "/* Test program generated by configurator. */\n"
 216 #define MAIN_START_BOILERPLATE "int main(int argc, char *argv[]) {\n"
 217 #define USE_FUNC_BOILERPLATE "(void)func;\n"
 218 #define MAIN_BODY_BOILERPLATE "return 0;\n"
 219 #define MAIN_END_BOILERPLATE "}\n"
 220
 221 static bool run_test(const char *cmd, struct test *test)
 222 {
 223         char *output;
 224         FILE *outf;
 225         int status;
 226
 227         if (test->done)
 228                 return test->answer;
 229
 230         if (test->depends && !run_test(cmd, find_test(test->depends))) {
 231                 test->answer = false;
 232                 test->done = true;
 233                 return test->answer;
 234         }
 235
 236         outf = fopen(INPUT_FILE, "w");
 237         if (!outf)
 238                 err(1, "creating %s", INPUT_FILE);
 239
 240         fprintf(outf, "%s", PRE_BOILERPLATE);
 241         switch (test->style) {
 242         case EXECUTE:
 243         case INSIDE_MAIN:
 244                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 245                 fprintf(outf, "%s", test->fragment);
 246                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 247                 break;
 248         case OUTSIDE_MAIN:
 249                 fprintf(outf, "%s", test->fragment);
 250                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 251                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 252                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 253                 break;
 254         case DEFINES_FUNC:
 255                 fprintf(outf, "%s", test->fragment);
 256                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
 257                 fprintf(outf, "%s", USE_FUNC_BOILERPLATE);
 258                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
 259                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
 260                 break;
 261         }
 262         fclose(outf);
 263
 264         if (verbose > 1)
 265                 if (system("cat " INPUT_FILE) == -1);
 266
 267         output = run(cmd, &status);
 268         if (status != 0) {
 269                 if (verbose)
 270                         printf("Compile fail for %s, status %i: %s\n",
 271                                test->name, status, output);
 272                 if (test->style == EXECUTE)
 273                         errx(1, "Test for %s did not compile:\n%s",
 274                              test->name, output);
 275                 test->answer = false;
 276                 free(output);
 277         } else {
 278                 /* Compile succeeded. */
 279                 free(output);
 280                 /* We run INSIDE_MAIN tests for sanity checking. */
 281                 if (test->style == EXECUTE || test->style == INSIDE_MAIN) {
 282                         output = run("./" OUTPUT_FILE, &status);
 283                         if (test->style == INSIDE_MAIN && status != 0)
 284                                 errx(1, "Test for %s failed with %i:\n%s",
 285                                      test->name, status, output);
 286                         if (verbose && status)
 287                                 printf("%s exited %i\n", test->name, status);
 288                         free(output);
 289                 }
 290                 test->answer = (status == 0);
 291         }
 292         test->done = true;
 293         return test->answer;
 294 }
 295
 296 int main(int argc, char *argv[])
 297 {
 298         char *cmd;
 299         char *default_args[] = { "", DEFAULT_COMPILER, DEFAULT_FLAGS, NULL };
 300         unsigned int i;
 301
 302         if (argc > 1) {
 303                 if (strcmp(argv[1], "--help") == 0) {
 304                         printf("Usage: configurator [-v] [<compiler> <flags>...]\n"
 305                                "  <compiler> <flags> will have \"-o <outfile> <infile.c>\" appended\n"
 306                                "Default: %s %s\n",
 307                                DEFAULT_COMPILER, DEFAULT_FLAGS);
 308                         exit(0);
 309                 }
 310                 if (strcmp(argv[1], "-v") == 0) {
 311                         argc--;
 312                         argv++;
 313                         verbose = 1;
 314                 } else if (strcmp(argv[1], "-vv") == 0) {
 315                         argc--;
 316                         argv++;
 317                         verbose = 2;
 318                 }
 319         }
 320
 321         if (argc == 1)
 322                 argv = default_args;
 323
 324         cmd = connect_args(argv, "-o " OUTPUT_FILE " " INPUT_FILE);
 325         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 326                 run_test(cmd, &tests[i]);
 327
 328         unlink(OUTPUT_FILE);
 329         unlink(INPUT_FILE);
 330
 331         cmd[strlen(cmd) - strlen(" -o " OUTPUT_FILE " " INPUT_FILE)] = '\0';
 332         printf("/* Generated by CCAN configurator */\n");
 333         printf("#define CCAN_COMPILER \"%s\"\n", argv[1]);
 334         printf("#define CCAN_CFLAGS \"%s\"\n\n", cmd + strlen(argv[1]) + 1);
 335         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
 336                 printf("#define %s %u\n", tests[i].name, tests[i].answer);
 337         return 0;
 338 }