4f2d2c8a99189b058e7610b101cbcd264dca186c
[ccan] / tools / ccanlint / tests / examples_compile.c
1 #include <tools/ccanlint/ccanlint.h>
2 #include <tools/tools.h>
3 #include <ccan/talloc/talloc.h>
4 #include <ccan/str/str.h>
5 #include <sys/types.h>
6 #include <sys/stat.h>
7 #include <fcntl.h>
8 #include <stdint.h>
9 #include <string.h>
10 #include <unistd.h>
11 #include <ctype.h>
12 #include <assert.h>
13
14 static const char *can_run(struct manifest *m)
15 {
16         if (safe_mode)
17                 return "Safe mode enabled";
18         return NULL;
19 }
20
21 /* FIXME: We should build if it doesn't exist... */
22 static bool expect_obj_file(const char *dir)
23 {
24         struct manifest *dep_man;
25         bool has_c_files;
26
27         dep_man = get_manifest(dir, dir);
28
29         /* If it has C files, we expect an object file built from them. */
30         has_c_files = !list_empty(&dep_man->c_files);
31         talloc_free(dep_man);
32         return has_c_files;
33 }
34
35 static char *add_dep(const struct manifest *m, char *list, const char *mod)
36 {
37         char **deps, *obj;
38         unsigned int i;
39
40         /* Not ourselves. */
41         if (streq(m->basename, mod))
42                 return list;
43
44         /* Not if there's no object file for that module */
45         if (!expect_obj_file(talloc_asprintf(list, "%s/ccan/%s", ccan_dir,mod)))
46                 return list;
47
48         obj = talloc_asprintf(list, "%s/ccan/%s.o", ccan_dir, mod);
49
50         /* Not anyone we've already included. */
51         if (strstr(list, obj))
52                 return list;
53
54         list = talloc_asprintf_append(list, " %s", obj);
55
56         /* Get that modules depends as well... */
57         assert(!safe_mode);
58         deps = get_deps(m, talloc_asprintf(list, "%s/ccan/%s", ccan_dir, mod),
59                         false, NULL);
60
61         for (i = 0; deps[i]; i++) {
62                 if (strstarts(deps[i], "ccan/"))
63                         list = add_dep(m, list, deps[i] + strlen("ccan/"));
64         }
65         return list;
66 }
67
68 static char *obj_list(const struct manifest *m, struct ccan_file *f)
69 {
70         char *list = talloc_strdup(m, "");
71         struct ccan_file *i;
72         char **lines;
73
74         /* Object files for this module. */
75         list_for_each(&m->c_files, i, list)
76                 list = talloc_asprintf_append(list, " %s", i->compiled);
77
78         /* Other ccan modules we depend on. */
79         list_for_each(&m->dep_dirs, i, list) {
80                 if (i->compiled)
81                         list = talloc_asprintf_append(list, " %s", i->compiled);
82         }
83
84         /* Other modules implied by includes. */
85         for (lines = get_ccan_file_lines(f); *lines; lines++) {
86                 unsigned preflen = strspn(*lines, " \t");
87                 if (strstarts(*lines + preflen, "#include <ccan/")) {
88                         const char *mod;
89                         unsigned modlen;
90
91                         mod = *lines + preflen + strlen("#include <ccan/");
92                         modlen = strcspn(mod, "/");
93                         mod = talloc_strndup(f, mod, modlen);
94                         list = add_dep(m, list, mod);
95                 }
96         }
97
98         return list;
99 }
100
101 static char *lib_list(const struct manifest *m)
102 {
103         unsigned int i, num;
104         char **libs = get_libs(m, ".", &num, &m->info_file->compiled);
105         char *ret = talloc_strdup(m, "");
106
107         for (i = 0; i < num; i++)
108                 ret = talloc_asprintf_append(ret, "-l%s ", libs[i]);
109         return ret;
110 }
111
112 static char *compile(const void *ctx,
113                      struct manifest *m,
114                      struct ccan_file *file,
115                      bool keep)
116 {
117         char *errmsg;
118
119         file->compiled = maybe_temp_file(ctx, "", keep, file->fullname);
120         errmsg = compile_and_link(ctx, file->fullname, ccan_dir,
121                                   obj_list(m, file),
122                                   "", lib_list(m), file->compiled);
123         if (errmsg) {
124                 talloc_free(file->compiled);
125                 return errmsg;
126         }
127         return NULL;
128 }
129
130 struct score {
131         unsigned int score;
132         char *errors;
133 };
134
135 static char *start_main(char *ret)
136 {
137         return talloc_asprintf_append(ret,
138                                       "/* Fake function wrapper inserted */\n"
139                                       "int main(int argc, char *argv[])\n"
140                                       "{\n");
141 }
142
143 /* We only handle simple function definitions here. */
144 static char *add_func(char *others, const char *line)
145 {
146         const char *p, *end = strchr(line, '(') - 1;
147         while (isblank(*end)) {
148                 end--;
149                 if (end == line)
150                         return others;
151         }
152
153         for (p = end; isalnum(*p) || *p == '_'; p--) {
154                 if (p == line)
155                         return others;
156         }
157
158         return talloc_asprintf_append(others, "printf(\"%%p\", %.*s);\n",
159                                       (unsigned)(end - p + 1), p);
160 }
161
162 static void strip_leading_whitespace(char **lines)
163 {
164         unsigned int i, min_span = -1U;
165
166         for (i = 0; lines[i]; i++) {
167                 unsigned int span = strspn(lines[i], " \t");
168                 /* All whitespace?  Ignore */
169                 if (!lines[i][span])
170                         continue;
171                 if (span < min_span)
172                         min_span = span;
173         }
174
175         for (i = 0; lines[i]; i++)
176                 if (strlen(lines[i]) >= min_span)
177                         lines[i] += min_span;
178 }
179
180 static bool looks_internal(char **lines)
181 {
182         unsigned int i;
183         bool last_ended = true; /* Did last line finish a statement? */
184
185         for (i = 0; lines[i]; i++) {
186                 /* Skip leading whitespace. */
187                 const char *line = lines[i] + strspn(lines[i], " \t");
188                 unsigned len = strspn(line, IDENT_CHARS);
189
190                 if (!line[0] || isblank(line[0]) || strstarts(line, "//"))
191                         continue;
192
193                 /* The winners. */
194                 if (strstarts(line, "if") && len == 2)
195                         return true;
196                 if (strstarts(line, "for") && len == 3)
197                         return true;
198                 if (strstarts(line, "while") && len == 5)
199                         return true;
200                 if (strstarts(line, "do") && len == 2)
201                         return true;
202
203                 /* The losers. */
204                 if (strstarts(line, "#include"))
205                         return false;
206
207                 if (last_ended && strchr(line, '(')) {
208                         if (strstarts(line, "static"))
209                                 return false;
210                         if (strends(line, ")"))
211                                 return false;
212                 }
213
214                 /* Single identifier then operator == inside function. */
215                 if (last_ended && len
216                     && ispunct(line[len+strspn(line+len, " ")]))
217                         return true;
218
219                 last_ended = (strends(line, "}")
220                               || strends(line, ";")
221                               || streq(line, "..."));
222         }
223
224         /* No idea... Say yes? */
225         return true;
226 }
227
228 /* Examples will often build on prior ones.  Try combining them. */
229 static char **combine(const void *ctx, char **lines, char **prev)
230 {
231         unsigned int i, lines_total, prev_total, count;
232         char **ret;
233
234         if (!prev)
235                 return NULL;
236
237         /* If it looks internal, put prev at start. */
238         if (looks_internal(lines)) {
239                 count = 0;
240         } else {
241                 /* Try inserting in first elided position */
242                 for (count = 0; lines[count]; count++) {
243                         if (strcmp(lines[count], "...") == 0)
244                                 break;
245                 }
246                 if (!lines[count])
247                         /* Try at start anyway? */
248                         count = 0;
249                 else
250                         count++;
251         }
252
253         for (i = 0; lines[i]; i++);
254         lines_total = i;
255
256         for (i = 0; prev[i]; i++);
257         prev_total = i;
258
259         ret = talloc_array(ctx, char *, lines_total + prev_total + 1);
260         memcpy(ret, lines, count * sizeof(ret[0]));
261         memcpy(ret + count, prev, prev_total * sizeof(ret[0]));
262         memcpy(ret + count + prev_total, lines + count,
263                (lines_total - count + 1) * sizeof(ret[0]));
264         return ret;
265 }
266
267 static char *mangle(struct manifest *m, char **lines)
268 {
269         char *ret, *use_funcs = NULL;
270         bool in_function = false, fake_function = false, has_main = false;
271         unsigned int i;
272
273         ret = talloc_strdup(m, "/* Prepend a heap of headers. */\n"
274                             "#include <assert.h>\n"
275                             "#include <err.h>\n"
276                             "#include <errno.h>\n"
277                             "#include <fcntl.h>\n"
278                             "#include <limits.h>\n"
279                             "#include <stdbool.h>\n"
280                             "#include <stdint.h>\n"
281                             "#include <stdio.h>\n"
282                             "#include <stdlib.h>\n"
283                             "#include <string.h>\n"
284                             "#include <sys/stat.h>\n"
285                             "#include <sys/types.h>\n"
286                             "#include <unistd.h>\n");
287         ret = talloc_asprintf_append(ret, "/* Include header from module. */\n"
288                                      "#include <ccan/%s/%s.h>\n",
289                                      m->basename, m->basename);
290
291         ret = talloc_asprintf_append(ret, "/* Useful dummy functions. */\n"
292                                      "extern int somefunc(void);\n"
293                                      "int somefunc(void) { return 0; }\n"
294                                      "extern char somestring[];\n"
295                                      "char somestring[] = \"hello world\";\n");
296
297         if (looks_internal(lines)) {
298                 /* Wrap it all in main(). */
299                 ret = start_main(ret);
300                 fake_function = true;
301                 in_function = true;
302                 has_main = true;
303         }
304
305         /* Primitive, very primitive. */
306         for (i = 0; lines[i]; i++) {
307                 /* } at start of line ends a function. */
308                 if (in_function) {
309                         if (lines[i][0] == '}')
310                                 in_function = false;
311                 } else {
312                         /* Character at start of line, with ( and no ;
313                          * == function start.  Ignore comments. */
314                         if (!isblank(lines[i][0])
315                             && strchr(lines[i], '(')
316                             && !strchr(lines[i], ';')
317                             && !strstr(lines[i], "//")) {
318                                 in_function = true;
319                                 if (strncmp(lines[i], "int main", 8) == 0)
320                                         has_main = true;
321                                 if (strncmp(lines[i], "static", 6) == 0) {
322                                         use_funcs = add_func(use_funcs,
323                                                              lines[i]);
324                                 }
325                         }
326                 }
327                 /* ... means elided code. */
328                 if (strcmp(lines[i], "...") == 0) {
329                         if (!in_function && !has_main
330                             && looks_internal(lines + i + 1)) {
331                                 /* This implies we start a function here. */
332                                 ret = start_main(ret);
333                                 has_main = true;
334                                 fake_function = true;
335                                 in_function = true;
336                         }
337                         ret = talloc_asprintf_append(ret,
338                                                      "/* ... removed */\n");
339                         continue;
340                 }
341                 ret = talloc_asprintf_append(ret, "%s\n", lines[i]);
342         }
343
344         /* Need a main to link successfully. */
345         if (!has_main) {
346                 ret = talloc_asprintf_append(ret, "int main(void)\n{\n");
347                 fake_function = true;
348         }
349
350         /* Get rid of unused warnings by printing addresses of static funcs. */
351         if (use_funcs) {
352                 if (!fake_function) {
353                         ret = talloc_asprintf_append(ret,
354                                                      "int use_funcs(void);\n"
355                                                      "int use_funcs(void) {\n");
356                         fake_function = true;
357                 }
358                 ret = talloc_asprintf_append(ret, "     %s\n", use_funcs);
359         }
360
361         if (fake_function)
362                 ret = talloc_asprintf_append(ret, "return 0;\n"
363                                              "}\n");
364         return ret;
365 }
366
367 static struct ccan_file *mangle_example(struct manifest *m,
368                                         struct ccan_file *example,
369                                         char **lines,
370                                         bool keep)
371 {
372         char *name, *contents;
373         int fd;
374         struct ccan_file *f;
375
376         name = maybe_temp_file(example, ".c", keep, 
377                                talloc_asprintf(m, "%s/mangled-%s",
378                                                m->dir, example->name));
379         f = new_ccan_file(example,
380                           talloc_dirname(example, name),
381                           talloc_basename(example, name));
382         talloc_steal(f, name);
383
384         fd = open(f->fullname, O_WRONLY | O_CREAT | O_EXCL, 0600);
385         if (fd < 0)
386                 return NULL;
387
388         contents = mangle(m, lines);
389         if (write(fd, contents, strlen(contents)) != strlen(contents)) {
390                 close(fd);
391                 return NULL;
392         }
393         close(fd);
394         f->contents = talloc_steal(f, contents);
395         return f;
396 }
397
398 static void *build_examples(struct manifest *m, bool keep,
399                             unsigned int *timeleft)
400 {
401         struct ccan_file *i;
402         struct score *score = talloc(m, struct score);
403         struct ccan_file *mangle;
404         char **prev = NULL;
405
406         score->score = 0;
407         score->errors = NULL;
408
409         list_for_each(&m->examples, i, list) {
410                 char *ret;
411
412                 examples_compile.total_score++;
413                 /* Simplify our dumb parsing. */
414                 strip_leading_whitespace(get_ccan_file_lines(i));
415                 ret = compile(score, m, i, keep);
416                 if (!ret) {
417                         prev = get_ccan_file_lines(i);
418                         score->score++;
419                         continue;
420                 }
421
422                 /* Try combining with previous (successful) example... */
423                 if (prev) {
424                         char **new = combine(i, get_ccan_file_lines(i), prev);
425                         talloc_free(ret);
426
427                         mangle = mangle_example(m, i, new, keep);
428                         ret = compile(score, m, mangle, keep);
429                         if (!ret) {
430                                 prev = new;
431                                 score->score++;
432                                 continue;
433                         }
434                 }
435
436                 /* Try standalone. */
437                 talloc_free(ret);
438                 mangle = mangle_example(m, i, get_ccan_file_lines(i), keep);
439                 ret = compile(score, m, mangle, keep);
440                 if (!ret) {
441                         prev = get_ccan_file_lines(i);
442                         score->score++;
443                         continue;
444                 }
445
446                 if (!score->errors)
447                         score->errors = ret;
448                 else {
449                         score->errors = talloc_append_string(score->errors,
450                                                              ret);
451                         talloc_free(ret);
452                 }
453                 /* This didn't work, so not a candidate for combining. */
454                 prev = NULL;
455         }
456         return score;
457 }
458
459 static unsigned int score_examples(struct manifest *m, void *check_result)
460 {
461         struct score *score = check_result;
462         return score->score;
463 }
464
465 static const char *describe(struct manifest *m, void *check_result)
466 {
467         struct score *score = check_result;
468         if (verbose >= 2 && score->errors)
469                 return talloc_asprintf(m, "Compile errors building examples:\n"
470                                        "%s", score->errors);
471         return NULL;
472 }
473
474 struct ccanlint examples_compile = {
475         .key = "examples-compile",
476         .name = "Module examples compile",
477         .score = score_examples,
478         .check = build_examples,
479         .describe = describe,
480         .can_run = can_run,
481 };
482
483 REGISTER_TEST(examples_compile, &has_examples, NULL);