1 /*
2 * docproc is a simple preprocessor for the template files
3 * used as placeholders for the kernel internal documentation.
4 * docproc is used for documentation-frontend and
5 * dependency-generator.
6 * The two usages have in common that they require
7 * some knowledge of the .tmpl syntax, therefore they
8 * are kept together.
9 *
10 * documentation-frontend
11 * Scans the template file and call kernel-doc for
12 * all occurrences of ![EIF]file
13 * Beforehand each referenced file is scanned for
14 * any symbols that are exported via these macros:
15 * EXPORT_SYMBOL(), EXPORT_SYMBOL_GPL(), &
16 * EXPORT_SYMBOL_GPL_FUTURE()
17 * This is used to create proper -function and
18 * -nofunction arguments in calls to kernel-doc.
19 * Usage: docproc doc file.tmpl
20 *
21 * dependency-generator:
22 * Scans the template file and list all files
23 * referenced in a format recognized by make.
24 * Usage: docproc depend file.tmpl
25 * Writes dependency information to stdout
26 * in the following format:
27 * file.tmpl src.c src2.c
28 * The filenames are obtained from the following constructs:
29 * !Efilename
30 * !Ifilename
31 * !Dfilename
32 * !Ffilename
33 * !Pfilename
34 *
35 */
36
37 #define _GNU_SOURCE
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <ctype.h>
42 #include <unistd.h>
43 #include <limits.h>
44 #include <errno.h>
45 #include <getopt.h>
46 #include <sys/types.h>
47 #include <sys/wait.h>
48 #include <time.h>
49
50 /* exitstatus is used to keep track of any failing calls to kernel-doc,
51 * but execution continues. */
52 int exitstatus = 0;
53
54 typedef void DFL(char *);
55 DFL *defaultline;
56
57 typedef void FILEONLY(char * file);
58 FILEONLY *internalfunctions;
59 FILEONLY *externalfunctions;
60 FILEONLY *symbolsonly;
61 FILEONLY *findall;
62
63 typedef void FILELINE(char * file, char * line);
64 FILELINE * singlefunctions;
65 FILELINE * entity_system;
66 FILELINE * docsection;
67
68 #define MAXLINESZ 2048
69 #define MAXFILES 250
70 #define KERNELDOCPATH "scripts/"
71 #define KERNELDOC "kernel-doc"
72 #define DOCBOOK "-docbook"
73 #define RST "-rst"
74 #define LIST "-list"
75 #define FUNCTION "-function"
76 #define NOFUNCTION "-nofunction"
77 #define NODOCSECTIONS "-no-doc-sections"
78 #define SHOWNOTFOUND "-show-not-found"
79
80 enum file_format {
81 FORMAT_AUTO,
82 FORMAT_DOCBOOK,
83 FORMAT_RST,
84 };
85
86 static enum file_format file_format = FORMAT_AUTO;
87
88 #define KERNELDOC_FORMAT (file_format == FORMAT_RST ? RST : DOCBOOK)
89
90 static char *srctree, *kernsrctree;
91
92 static char **all_list = NULL;
93 static int all_list_len = 0;
94
consume_symbol(const char * sym)95 static void consume_symbol(const char *sym)
96 {
97 int i;
98
99 for (i = 0; i < all_list_len; i++) {
100 if (!all_list[i])
101 continue;
102 if (strcmp(sym, all_list[i]))
103 continue;
104 all_list[i] = NULL;
105 break;
106 }
107 }
108
usage(void)109 static void usage (void)
110 {
111 fprintf(stderr, "Usage: docproc [{--docbook|--rst}] {doc|depend} file\n");
112 fprintf(stderr, "Input is read from file.tmpl. Output is sent to stdout\n");
113 fprintf(stderr, "doc: frontend when generating kernel documentation\n");
114 fprintf(stderr, "depend: generate list of files referenced within file\n");
115 fprintf(stderr, "Environment variable SRCTREE: absolute path to sources.\n");
116 fprintf(stderr, " KBUILD_SRC: absolute path to kernel source tree.\n");
117 }
118
119 /*
120 * Execute kernel-doc with parameters given in svec
121 */
exec_kernel_doc(char ** svec)122 static void exec_kernel_doc(char **svec)
123 {
124 pid_t pid;
125 int ret;
126 char real_filename[PATH_MAX + 1];
127 /* Make sure output generated so far are flushed */
128 fflush(stdout);
129 switch (pid=fork()) {
130 case -1:
131 perror("fork");
132 exit(1);
133 case 0:
134 memset(real_filename, 0, sizeof(real_filename));
135 strncat(real_filename, kernsrctree, PATH_MAX);
136 strncat(real_filename, "/" KERNELDOCPATH KERNELDOC,
137 PATH_MAX - strlen(real_filename));
138 execvp(real_filename, svec);
139 fprintf(stderr, "exec ");
140 perror(real_filename);
141 exit(1);
142 default:
143 waitpid(pid, &ret ,0);
144 }
145 if (WIFEXITED(ret))
146 exitstatus |= WEXITSTATUS(ret);
147 else
148 exitstatus = 0xff;
149 }
150
151 /* Types used to create list of all exported symbols in a number of files */
152 struct symbols
153 {
154 char *name;
155 };
156
157 struct symfile
158 {
159 char *filename;
160 struct symbols *symbollist;
161 int symbolcnt;
162 };
163
164 struct symfile symfilelist[MAXFILES];
165 int symfilecnt = 0;
166
add_new_symbol(struct symfile * sym,char * symname)167 static void add_new_symbol(struct symfile *sym, char * symname)
168 {
169 sym->symbollist =
170 realloc(sym->symbollist, (sym->symbolcnt + 1) * sizeof(char *));
171 sym->symbollist[sym->symbolcnt++].name = strdup(symname);
172 }
173
174 /* Add a filename to the list */
add_new_file(char * filename)175 static struct symfile * add_new_file(char * filename)
176 {
177 symfilelist[symfilecnt++].filename = strdup(filename);
178 return &symfilelist[symfilecnt - 1];
179 }
180
181 /* Check if file already are present in the list */
filename_exist(char * filename)182 static struct symfile * filename_exist(char * filename)
183 {
184 int i;
185 for (i=0; i < symfilecnt; i++)
186 if (strcmp(symfilelist[i].filename, filename) == 0)
187 return &symfilelist[i];
188 return NULL;
189 }
190
191 /*
192 * List all files referenced within the template file.
193 * Files are separated by tabs.
194 */
adddep(char * file)195 static void adddep(char * file) { printf("\t%s", file); }
adddep2(char * file,char * line)196 static void adddep2(char * file, char * line) { line = line; adddep(file); }
noaction(char * line)197 static void noaction(char * line) { line = line; }
noaction2(char * file,char * line)198 static void noaction2(char * file, char * line) { file = file; line = line; }
199
200 /* Echo the line without further action */
printline(char * line)201 static void printline(char * line) { printf("%s", line); }
202
203 /*
204 * Find all symbols in filename that are exported with EXPORT_SYMBOL &
205 * EXPORT_SYMBOL_GPL (& EXPORT_SYMBOL_GPL_FUTURE implicitly).
206 * All symbols located are stored in symfilelist.
207 */
find_export_symbols(char * filename)208 static void find_export_symbols(char * filename)
209 {
210 FILE * fp;
211 struct symfile *sym;
212 char line[MAXLINESZ];
213 if (filename_exist(filename) == NULL) {
214 char real_filename[PATH_MAX + 1];
215 memset(real_filename, 0, sizeof(real_filename));
216 strncat(real_filename, srctree, PATH_MAX);
217 strncat(real_filename, "/", PATH_MAX - strlen(real_filename));
218 strncat(real_filename, filename,
219 PATH_MAX - strlen(real_filename));
220 sym = add_new_file(filename);
221 fp = fopen(real_filename, "r");
222 if (fp == NULL) {
223 fprintf(stderr, "docproc: ");
224 perror(real_filename);
225 exit(1);
226 }
227 while (fgets(line, MAXLINESZ, fp)) {
228 char *p;
229 char *e;
230 if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) ||
231 ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) {
232 /* Skip EXPORT_SYMBOL{_GPL} */
233 while (isalnum(*p) || *p == '_')
234 p++;
235 /* Remove parentheses & additional whitespace */
236 while (isspace(*p))
237 p++;
238 if (*p != '(')
239 continue; /* Syntax error? */
240 else
241 p++;
242 while (isspace(*p))
243 p++;
244 e = p;
245 while (isalnum(*e) || *e == '_')
246 e++;
247 *e = '\0';
248 add_new_symbol(sym, p);
249 }
250 }
251 fclose(fp);
252 }
253 }
254
255 /*
256 * Document all external or internal functions in a file.
257 * Call kernel-doc with following parameters:
258 * kernel-doc [-docbook|-rst] -nofunction function_name1 filename
259 * Function names are obtained from all the src files
260 * by find_export_symbols.
261 * intfunc uses -nofunction
262 * extfunc uses -function
263 */
docfunctions(char * filename,char * type)264 static void docfunctions(char * filename, char * type)
265 {
266 int i,j;
267 int symcnt = 0;
268 int idx = 0;
269 char **vec;
270
271 for (i=0; i <= symfilecnt; i++)
272 symcnt += symfilelist[i].symbolcnt;
273 vec = malloc((2 + 2 * symcnt + 3) * sizeof(char *));
274 if (vec == NULL) {
275 perror("docproc: ");
276 exit(1);
277 }
278 vec[idx++] = KERNELDOC;
279 vec[idx++] = KERNELDOC_FORMAT;
280 vec[idx++] = NODOCSECTIONS;
281 for (i=0; i < symfilecnt; i++) {
282 struct symfile * sym = &symfilelist[i];
283 for (j=0; j < sym->symbolcnt; j++) {
284 vec[idx++] = type;
285 consume_symbol(sym->symbollist[j].name);
286 vec[idx++] = sym->symbollist[j].name;
287 }
288 }
289 vec[idx++] = filename;
290 vec[idx] = NULL;
291 if (file_format == FORMAT_RST)
292 printf(".. %s\n", filename);
293 else
294 printf("<!-- %s -->\n", filename);
295 exec_kernel_doc(vec);
296 fflush(stdout);
297 free(vec);
298 }
intfunc(char * filename)299 static void intfunc(char * filename) { docfunctions(filename, NOFUNCTION); }
extfunc(char * filename)300 static void extfunc(char * filename) { docfunctions(filename, FUNCTION); }
301
302 /*
303 * Document specific function(s) in a file.
304 * Call kernel-doc with the following parameters:
305 * kernel-doc -docbook -function function1 [-function function2]
306 */
singfunc(char * filename,char * line)307 static void singfunc(char * filename, char * line)
308 {
309 char *vec[200]; /* Enough for specific functions */
310 int i, idx = 0;
311 int startofsym = 1;
312 vec[idx++] = KERNELDOC;
313 vec[idx++] = KERNELDOC_FORMAT;
314 vec[idx++] = SHOWNOTFOUND;
315
316 /* Split line up in individual parameters preceded by FUNCTION */
317 for (i=0; line[i]; i++) {
318 if (isspace(line[i])) {
319 line[i] = '\0';
320 startofsym = 1;
321 continue;
322 }
323 if (startofsym) {
324 startofsym = 0;
325 vec[idx++] = FUNCTION;
326 vec[idx++] = &line[i];
327 }
328 }
329 for (i = 0; i < idx; i++) {
330 if (strcmp(vec[i], FUNCTION))
331 continue;
332 consume_symbol(vec[i + 1]);
333 }
334 vec[idx++] = filename;
335 vec[idx] = NULL;
336 exec_kernel_doc(vec);
337 }
338
339 /*
340 * Insert specific documentation section from a file.
341 * Call kernel-doc with the following parameters:
342 * kernel-doc -docbook -function "doc section" filename
343 */
docsect(char * filename,char * line)344 static void docsect(char *filename, char *line)
345 {
346 /* kerneldoc -docbook -show-not-found -function "section" file NULL */
347 char *vec[7];
348 char *s;
349
350 for (s = line; *s; s++)
351 if (*s == '\n')
352 *s = '\0';
353
354 if (asprintf(&s, "DOC: %s", line) < 0) {
355 perror("asprintf");
356 exit(1);
357 }
358 consume_symbol(s);
359 free(s);
360
361 vec[0] = KERNELDOC;
362 vec[1] = KERNELDOC_FORMAT;
363 vec[2] = SHOWNOTFOUND;
364 vec[3] = FUNCTION;
365 vec[4] = line;
366 vec[5] = filename;
367 vec[6] = NULL;
368 exec_kernel_doc(vec);
369 }
370
find_all_symbols(char * filename)371 static void find_all_symbols(char *filename)
372 {
373 char *vec[4]; /* kerneldoc -list file NULL */
374 pid_t pid;
375 int ret, i, count, start;
376 char real_filename[PATH_MAX + 1];
377 int pipefd[2];
378 char *data, *str;
379 size_t data_len = 0;
380
381 vec[0] = KERNELDOC;
382 vec[1] = LIST;
383 vec[2] = filename;
384 vec[3] = NULL;
385
386 if (pipe(pipefd)) {
387 perror("pipe");
388 exit(1);
389 }
390
391 switch (pid=fork()) {
392 case -1:
393 perror("fork");
394 exit(1);
395 case 0:
396 close(pipefd[0]);
397 dup2(pipefd[1], 1);
398 memset(real_filename, 0, sizeof(real_filename));
399 strncat(real_filename, kernsrctree, PATH_MAX);
400 strncat(real_filename, "/" KERNELDOCPATH KERNELDOC,
401 PATH_MAX - strlen(real_filename));
402 execvp(real_filename, vec);
403 fprintf(stderr, "exec ");
404 perror(real_filename);
405 exit(1);
406 default:
407 close(pipefd[1]);
408 data = malloc(4096);
409 do {
410 while ((ret = read(pipefd[0],
411 data + data_len,
412 4096)) > 0) {
413 data_len += ret;
414 data = realloc(data, data_len + 4096);
415 }
416 } while (ret == -EAGAIN);
417 if (ret != 0) {
418 perror("read");
419 exit(1);
420 }
421 waitpid(pid, &ret ,0);
422 }
423 if (WIFEXITED(ret))
424 exitstatus |= WEXITSTATUS(ret);
425 else
426 exitstatus = 0xff;
427
428 count = 0;
429 /* poor man's strtok, but with counting */
430 for (i = 0; i < data_len; i++) {
431 if (data[i] == '\n') {
432 count++;
433 data[i] = '\0';
434 }
435 }
436 start = all_list_len;
437 all_list_len += count;
438 all_list = realloc(all_list, sizeof(char *) * all_list_len);
439 str = data;
440 for (i = 0; i < data_len && start != all_list_len; i++) {
441 if (data[i] == '\0') {
442 all_list[start] = str;
443 str = data + i + 1;
444 start++;
445 }
446 }
447 }
448
449 /*
450 * Terminate s at first space, if any. If there was a space, return pointer to
451 * the character after that. Otherwise, return pointer to the terminating NUL.
452 */
chomp(char * s)453 static char *chomp(char *s)
454 {
455 while (*s && !isspace(*s))
456 s++;
457
458 if (*s)
459 *s++ = '\0';
460
461 return s;
462 }
463
464 /* Return pointer to directive content, or NULL if not a directive. */
is_directive(char * line)465 static char *is_directive(char *line)
466 {
467 if (file_format == FORMAT_DOCBOOK && line[0] == '!')
468 return line + 1;
469 else if (file_format == FORMAT_RST && !strncmp(line, ".. !", 4))
470 return line + 4;
471
472 return NULL;
473 }
474
475 /*
476 * Parse file, calling action specific functions for:
477 * 1) Lines containing !E
478 * 2) Lines containing !I
479 * 3) Lines containing !D
480 * 4) Lines containing !F
481 * 5) Lines containing !P
482 * 6) Lines containing !C
483 * 7) Default lines - lines not matching the above
484 */
parse_file(FILE * infile)485 static void parse_file(FILE *infile)
486 {
487 char line[MAXLINESZ];
488 char *p, *s;
489 while (fgets(line, MAXLINESZ, infile)) {
490 p = is_directive(line);
491 if (!p) {
492 defaultline(line);
493 continue;
494 }
495
496 switch (*p++) {
497 case 'E':
498 chomp(p);
499 externalfunctions(p);
500 break;
501 case 'I':
502 chomp(p);
503 internalfunctions(p);
504 break;
505 case 'D':
506 chomp(p);
507 symbolsonly(p);
508 break;
509 case 'F':
510 /* filename */
511 s = chomp(p);
512 /* function names */
513 while (isspace(*s))
514 s++;
515 singlefunctions(p, s);
516 break;
517 case 'P':
518 /* filename */
519 s = chomp(p);
520 /* DOC: section name */
521 while (isspace(*s))
522 s++;
523 docsection(p, s);
524 break;
525 case 'C':
526 chomp(p);
527 if (findall)
528 findall(p);
529 break;
530 default:
531 defaultline(line);
532 }
533 }
534 fflush(stdout);
535 }
536
537 /*
538 * Is this a RestructuredText template? Answer the question by seeing if its
539 * name ends in ".rst".
540 */
is_rst(const char * file)541 static int is_rst(const char *file)
542 {
543 char *dot = strrchr(file, '.');
544
545 return dot && !strcmp(dot + 1, "rst");
546 }
547
548 enum opts {
549 OPT_DOCBOOK,
550 OPT_RST,
551 OPT_HELP,
552 };
553
main(int argc,char * argv[])554 int main(int argc, char *argv[])
555 {
556 const char *subcommand, *filename;
557 FILE * infile;
558 int i;
559
560 srctree = getenv("SRCTREE");
561 if (!srctree)
562 srctree = getcwd(NULL, 0);
563 kernsrctree = getenv("KBUILD_SRC");
564 if (!kernsrctree || !*kernsrctree)
565 kernsrctree = srctree;
566
567 for (;;) {
568 int c;
569 struct option opts[] = {
570 { "docbook", no_argument, NULL, OPT_DOCBOOK },
571 { "rst", no_argument, NULL, OPT_RST },
572 { "help", no_argument, NULL, OPT_HELP },
573 {}
574 };
575
576 c = getopt_long_only(argc, argv, "", opts, NULL);
577 if (c == -1)
578 break;
579
580 switch (c) {
581 case OPT_DOCBOOK:
582 file_format = FORMAT_DOCBOOK;
583 break;
584 case OPT_RST:
585 file_format = FORMAT_RST;
586 break;
587 case OPT_HELP:
588 usage();
589 return 0;
590 default:
591 case '?':
592 usage();
593 return 1;
594 }
595 }
596
597 argc -= optind;
598 argv += optind;
599
600 if (argc != 2) {
601 usage();
602 exit(1);
603 }
604
605 subcommand = argv[0];
606 filename = argv[1];
607
608 if (file_format == FORMAT_AUTO)
609 file_format = is_rst(filename) ? FORMAT_RST : FORMAT_DOCBOOK;
610
611 /* Open file, exit on error */
612 infile = fopen(filename, "r");
613 if (infile == NULL) {
614 fprintf(stderr, "docproc: ");
615 perror(filename);
616 exit(2);
617 }
618
619 if (strcmp("doc", subcommand) == 0) {
620 if (file_format == FORMAT_RST) {
621 time_t t = time(NULL);
622 printf(".. generated from %s by docproc %s\n",
623 filename, ctime(&t));
624 }
625
626 /* Need to do this in two passes.
627 * First pass is used to collect all symbols exported
628 * in the various files;
629 * Second pass generate the documentation.
630 * This is required because some functions are declared
631 * and exported in different files :-((
632 */
633 /* Collect symbols */
634 defaultline = noaction;
635 internalfunctions = find_export_symbols;
636 externalfunctions = find_export_symbols;
637 symbolsonly = find_export_symbols;
638 singlefunctions = noaction2;
639 docsection = noaction2;
640 findall = find_all_symbols;
641 parse_file(infile);
642
643 /* Rewind to start from beginning of file again */
644 fseek(infile, 0, SEEK_SET);
645 defaultline = printline;
646 internalfunctions = intfunc;
647 externalfunctions = extfunc;
648 symbolsonly = printline;
649 singlefunctions = singfunc;
650 docsection = docsect;
651 findall = NULL;
652
653 parse_file(infile);
654
655 for (i = 0; i < all_list_len; i++) {
656 if (!all_list[i])
657 continue;
658 fprintf(stderr, "Warning: didn't use docs for %s\n",
659 all_list[i]);
660 }
661 } else if (strcmp("depend", subcommand) == 0) {
662 /* Create first part of dependency chain
663 * file.tmpl */
664 printf("%s\t", filename);
665 defaultline = noaction;
666 internalfunctions = adddep;
667 externalfunctions = adddep;
668 symbolsonly = adddep;
669 singlefunctions = adddep2;
670 docsection = adddep2;
671 findall = adddep;
672 parse_file(infile);
673 printf("\n");
674 } else {
675 fprintf(stderr, "Unknown option: %s\n", subcommand);
676 exit(1);
677 }
678 fclose(infile);
679 fflush(stdout);
680 return exitstatus;
681 }
682