configurator: warnings count as failures too.
[ccan] / 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         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_FFSLL", INSIDE_MAIN, NULL,
75           "return __builtin_ffsll(0LL) == 0 ? 0 : 1;" },
76         { "HAVE_BUILTIN_POPCOUNTL", INSIDE_MAIN, NULL,
77           "return __builtin_popcountl(255L) == 8 ? 0 : 1;" },
78         { "HAVE_BUILTIN_TYPES_COMPATIBLE_P", INSIDE_MAIN, NULL,
79           "return __builtin_types_compatible_p(char *, int) ? 1 : 0;" },
80         { "HAVE_BYTESWAP_H", OUTSIDE_MAIN, NULL,
81           "#include <byteswap.h>\n" },
82         { "HAVE_COMPOUND_LITERALS", INSIDE_MAIN, NULL,
83           "char **foo = (char *[]) { \"x\", \"y\", \"z\" };\n"
84           "return foo[0] ? 0 : 1;" },
85         { "HAVE_FOR_LOOP_DECLARATION", INSIDE_MAIN, NULL,
86           "for (int i = 0; i < argc; i++) { return 0; };\n"
87           "return 1;" },
88         { "HAVE_GETPAGESIZE", DEFINES_FUNC, NULL,
89           "#include <unistd.h>\n"
90           "static int func(void) { return getpagesize(); }" },
91         { "HAVE_LITTLE_ENDIAN", EXECUTE, NULL,
92           "union { int i; char c[sizeof(int)]; } u;\n"
93           "u.i = 0x01020304;\n"
94           "return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;" },
95         { "HAVE_MMAP", DEFINES_FUNC, NULL,
96           "#include <sys/mman.h>\n"
97           "static void *func(int fd) {\n"
98           "     return mmap(0, 65536, PROT_READ, MAP_SHARED, fd, 0);\n"
99           "}" },
100         { "HAVE_NESTED_FUNCTIONS", DEFINES_FUNC, NULL,
101           "static int func(int val) {\n"
102           "     auto void add(int val2);\n"
103           "     void add(int val2) { val += val2; }\n"
104           "     add(7);\n"
105           "     return val;\n"
106           "}" },
107         { "HAVE_STATEMENT_EXPR", INSIDE_MAIN, NULL,
108           "return ({ int x = argc; x == argc ? 0 : 1; });" },
109         { "HAVE_TYPEOF", INSIDE_MAIN, NULL,
110           "__typeof__(argc) i; i = argc; return i == argc ? 0 : 1;" },
111         { "HAVE_UTIME", DEFINES_FUNC, NULL,
112           "#include <sys/types.h>\n"
113           "#include <utime.h>\n"
114           "static int func(const char *filename) {\n"
115           "     struct utimbuf times = { 0 };\n"
116           "     return utime(filename, &times);\n"
117           "}" },
118         { "HAVE_WARN_UNUSED_RESULT", DEFINES_FUNC, NULL,
119           "#include <sys/types.h>\n"
120           "#include <utime.h>\n"
121           "static __attribute__((warn_unused_result)) int func(int i) {\n"
122           "     return i + 1;\n"
123           "}" },
124 };
125
126 static char *grab_fd(int fd)
127 {
128         int ret;
129         size_t max, size = 0;
130         char *buffer;
131
132         max = 16384;
133         buffer = malloc(max+1);
134         while ((ret = read(fd, buffer + size, max - size)) > 0) {
135                 size += ret;
136                 if (size == max)
137                         buffer = realloc(buffer, max *= 2);
138         }
139         if (ret < 0)
140                 err(1, "reading from command");
141         buffer[size] = '\0';
142         return buffer;
143 }
144
145 static char *run(const char *cmd, int *exitstatus)
146 {
147         pid_t pid;
148         int p[2];
149         char *ret;
150         int status;
151
152         if (pipe(p) != 0)
153                 err(1, "creating pipe");
154
155         pid = fork();
156         if (pid == -1)
157                 err(1, "forking");
158
159         if (pid == 0) {
160                 if (dup2(p[1], STDOUT_FILENO) != STDOUT_FILENO
161                     || dup2(p[1], STDERR_FILENO) != STDERR_FILENO
162                     || close(p[0]) != 0
163                     || close(STDIN_FILENO) != 0
164                     || open("/dev/null", O_RDONLY) != STDIN_FILENO)
165                         exit(128);
166
167                 status = system(cmd);
168                 if (WIFEXITED(status))
169                         exit(WEXITSTATUS(status));
170                 /* Here's a hint... */
171                 exit(128 + WTERMSIG(status));
172         }
173
174         close(p[1]);
175         ret = grab_fd(p[0]);
176         /* This shouldn't fail... */
177         if (waitpid(pid, &status, 0) != pid)
178                 err(1, "Failed to wait for child");
179         close(p[0]);
180         if (WIFEXITED(status))
181                 *exitstatus = WEXITSTATUS(status);
182         else
183                 *exitstatus = -WTERMSIG(status);
184         return ret;
185 }
186
187 static char *connect_args(char *argv[], const char *extra)
188 {
189         unsigned int i, len = strlen(extra) + 1;
190         char *ret;
191
192         for (i = 1; argv[i]; i++)
193                 len += 1 + strlen(argv[i]);
194
195         ret = malloc(len);
196         len = 0;
197         for (i = 1; argv[i]; i++) {
198                 strcpy(ret + len, argv[i]);
199                 len += strlen(argv[i]);
200                 ret[len++] = ' ';
201         }
202         strcpy(ret + len, extra);
203         return ret;
204 }
205
206 static struct test *find_test(const char *name)
207 {
208         unsigned int i;
209
210         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
211                 if (strcmp(tests[i].name, name) == 0)
212                         return &tests[i];
213         }
214         abort();
215 }
216
217 #define PRE_BOILERPLATE "/* Test program generated by configurator. */\n"
218 #define MAIN_START_BOILERPLATE "int main(int argc, char *argv[]) {\n"
219 #define USE_FUNC_BOILERPLATE "(void)func;\n"
220 #define MAIN_BODY_BOILERPLATE "return 0;\n"
221 #define MAIN_END_BOILERPLATE "}\n"
222
223 static bool run_test(const char *cmd, struct test *test)
224 {
225         char *output;
226         FILE *outf;
227         int status;
228
229         if (test->done)
230                 return test->answer;
231
232         if (test->depends && !run_test(cmd, find_test(test->depends))) {
233                 test->answer = false;
234                 test->done = true;
235                 return test->answer;
236         }
237
238         outf = fopen(INPUT_FILE, "w");
239         if (!outf)
240                 err(1, "creating %s", INPUT_FILE);
241
242         fprintf(outf, "%s", PRE_BOILERPLATE);
243         switch (test->style) {
244         case EXECUTE:
245         case INSIDE_MAIN:
246                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
247                 fprintf(outf, "%s", test->fragment);
248                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
249                 break;
250         case OUTSIDE_MAIN:
251                 fprintf(outf, "%s", test->fragment);
252                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
253                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
254                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
255                 break;
256         case DEFINES_FUNC:
257                 fprintf(outf, "%s", test->fragment);
258                 fprintf(outf, "%s", MAIN_START_BOILERPLATE);
259                 fprintf(outf, "%s", USE_FUNC_BOILERPLATE);
260                 fprintf(outf, "%s", MAIN_BODY_BOILERPLATE);
261                 fprintf(outf, "%s", MAIN_END_BOILERPLATE);
262                 break;
263         }
264         fclose(outf);
265
266         if (verbose > 1)
267                 if (system("cat " INPUT_FILE) == -1);
268
269         output = run(cmd, &status);
270         if (status != 0 || strstr(output, "warning")) {
271                 if (verbose)
272                         printf("Compile %s for %s, status %i: %s\n",
273                                status ? "fail" : "warning",
274                                test->name, status, output);
275                 if (test->style == EXECUTE)
276                         errx(1, "Test for %s did not compile:\n%s",
277                              test->name, output);
278                 test->answer = false;
279                 free(output);
280         } else {
281                 /* Compile succeeded. */
282                 free(output);
283                 /* We run INSIDE_MAIN tests for sanity checking. */
284                 if (test->style == EXECUTE || test->style == INSIDE_MAIN) {
285                         output = run("./" OUTPUT_FILE, &status);
286                         if (test->style == INSIDE_MAIN && status != 0)
287                                 errx(1, "Test for %s failed with %i:\n%s",
288                                      test->name, status, output);
289                         if (verbose && status)
290                                 printf("%s exited %i\n", test->name, status);
291                         free(output);
292                 }
293                 test->answer = (status == 0);
294         }
295         test->done = true;
296         return test->answer;
297 }
298
299 int main(int argc, char *argv[])
300 {
301         char *cmd;
302         char *default_args[] = { "", DEFAULT_COMPILER, DEFAULT_FLAGS, NULL };
303         unsigned int i;
304
305         if (argc > 1) {
306                 if (strcmp(argv[1], "--help") == 0) {
307                         printf("Usage: configurator [-v] [<compiler> <flags>...]\n"
308                                "  <compiler> <flags> will have \"-o <outfile> <infile.c>\" appended\n"
309                                "Default: %s %s\n",
310                                DEFAULT_COMPILER, DEFAULT_FLAGS);
311                         exit(0);
312                 }
313                 if (strcmp(argv[1], "-v") == 0) {
314                         argc--;
315                         argv++;
316                         verbose = 1;
317                 } else if (strcmp(argv[1], "-vv") == 0) {
318                         argc--;
319                         argv++;
320                         verbose = 2;
321                 }
322         }
323
324         if (argc == 1)
325                 argv = default_args;
326
327         cmd = connect_args(argv, "-o " OUTPUT_FILE " " INPUT_FILE);
328         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
329                 run_test(cmd, &tests[i]);
330
331         unlink(OUTPUT_FILE);
332         unlink(INPUT_FILE);
333
334         cmd[strlen(cmd) - strlen(" -o " OUTPUT_FILE " " INPUT_FILE)] = '\0';
335         printf("/* Generated by CCAN configurator */\n");
336         printf("#define CCAN_COMPILER \"%s\"\n", argv[1]);
337         printf("#define CCAN_CFLAGS \"%s\"\n\n", cmd + strlen(argv[1]) + 1);
338         for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
339                 printf("#define %s %u\n", tests[i].name, tests[i].answer);
340         return 0;
341 }