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[linux-2.6.git] / scripts / docproc.c
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 <sys/types.h>
46 #include <sys/wait.h>
47
48 /* exitstatus is used to keep track of any failing calls to kernel-doc,
49  * but execution continues. */
50 int exitstatus = 0;
51
52 typedef void DFL(char *);
53 DFL *defaultline;
54
55 typedef void FILEONLY(char * file);
56 FILEONLY *internalfunctions;
57 FILEONLY *externalfunctions;
58 FILEONLY *symbolsonly;
59 FILEONLY *findall;
60
61 typedef void FILELINE(char * file, char * line);
62 FILELINE * singlefunctions;
63 FILELINE * entity_system;
64 FILELINE * docsection;
65
66 #define MAXLINESZ     2048
67 #define MAXFILES      250
68 #define KERNELDOCPATH "scripts/"
69 #define KERNELDOC     "kernel-doc"
70 #define DOCBOOK       "-docbook"
71 #define LIST          "-list"
72 #define FUNCTION      "-function"
73 #define NOFUNCTION    "-nofunction"
74 #define NODOCSECTIONS "-no-doc-sections"
75
76 static char *srctree, *kernsrctree;
77
78 static char **all_list = NULL;
79 static int all_list_len = 0;
80
81 static void consume_symbol(const char *sym)
82 {
83         int i;
84
85         for (i = 0; i < all_list_len; i++) {
86                 if (!all_list[i])
87                         continue;
88                 if (strcmp(sym, all_list[i]))
89                         continue;
90                 all_list[i] = NULL;
91                 break;
92         }
93 }
94
95 static void usage (void)
96 {
97         fprintf(stderr, "Usage: docproc {doc|depend} file\n");
98         fprintf(stderr, "Input is read from file.tmpl. Output is sent to stdout\n");
99         fprintf(stderr, "doc: frontend when generating kernel documentation\n");
100         fprintf(stderr, "depend: generate list of files referenced within file\n");
101         fprintf(stderr, "Environment variable SRCTREE: absolute path to sources.\n");
102         fprintf(stderr, "                     KBUILD_SRC: absolute path to kernel source tree.\n");
103 }
104
105 /*
106  * Execute kernel-doc with parameters given in svec
107  */
108 static void exec_kernel_doc(char **svec)
109 {
110         pid_t pid;
111         int ret;
112         char real_filename[PATH_MAX + 1];
113         /* Make sure output generated so far are flushed */
114         fflush(stdout);
115         switch (pid=fork()) {
116                 case -1:
117                         perror("fork");
118                         exit(1);
119                 case  0:
120                         memset(real_filename, 0, sizeof(real_filename));
121                         strncat(real_filename, kernsrctree, PATH_MAX);
122                         strncat(real_filename, "/" KERNELDOCPATH KERNELDOC,
123                                         PATH_MAX - strlen(real_filename));
124                         execvp(real_filename, svec);
125                         fprintf(stderr, "exec ");
126                         perror(real_filename);
127                         exit(1);
128                 default:
129                         waitpid(pid, &ret ,0);
130         }
131         if (WIFEXITED(ret))
132                 exitstatus |= WEXITSTATUS(ret);
133         else
134                 exitstatus = 0xff;
135 }
136
137 /* Types used to create list of all exported symbols in a number of files */
138 struct symbols
139 {
140         char *name;
141 };
142
143 struct symfile
144 {
145         char *filename;
146         struct symbols *symbollist;
147         int symbolcnt;
148 };
149
150 struct symfile symfilelist[MAXFILES];
151 int symfilecnt = 0;
152
153 static void add_new_symbol(struct symfile *sym, char * symname)
154 {
155         sym->symbollist =
156           realloc(sym->symbollist, (sym->symbolcnt + 1) * sizeof(char *));
157         sym->symbollist[sym->symbolcnt++].name = strdup(symname);
158 }
159
160 /* Add a filename to the list */
161 static struct symfile * add_new_file(char * filename)
162 {
163         symfilelist[symfilecnt++].filename = strdup(filename);
164         return &symfilelist[symfilecnt - 1];
165 }
166
167 /* Check if file already are present in the list */
168 static struct symfile * filename_exist(char * filename)
169 {
170         int i;
171         for (i=0; i < symfilecnt; i++)
172                 if (strcmp(symfilelist[i].filename, filename) == 0)
173                         return &symfilelist[i];
174         return NULL;
175 }
176
177 /*
178  * List all files referenced within the template file.
179  * Files are separated by tabs.
180  */
181 static void adddep(char * file)            { printf("\t%s", file); }
182 static void adddep2(char * file, char * line)     { line = line; adddep(file); }
183 static void noaction(char * line)                  { line = line; }
184 static void noaction2(char * file, char * line)   { file = file; line = line; }
185
186 /* Echo the line without further action */
187 static void printline(char * line)               { printf("%s", line); }
188
189 /*
190  * Find all symbols in filename that are exported with EXPORT_SYMBOL &
191  * EXPORT_SYMBOL_GPL (& EXPORT_SYMBOL_GPL_FUTURE implicitly).
192  * All symbols located are stored in symfilelist.
193  */
194 static void find_export_symbols(char * filename)
195 {
196         FILE * fp;
197         struct symfile *sym;
198         char line[MAXLINESZ];
199         if (filename_exist(filename) == NULL) {
200                 char real_filename[PATH_MAX + 1];
201                 memset(real_filename, 0, sizeof(real_filename));
202                 strncat(real_filename, srctree, PATH_MAX);
203                 strncat(real_filename, "/", PATH_MAX - strlen(real_filename));
204                 strncat(real_filename, filename,
205                                 PATH_MAX - strlen(real_filename));
206                 sym = add_new_file(filename);
207                 fp = fopen(real_filename, "r");
208                 if (fp == NULL)
209                 {
210                         fprintf(stderr, "docproc: ");
211                         perror(real_filename);
212                         exit(1);
213                 }
214                 while (fgets(line, MAXLINESZ, fp)) {
215                         char *p;
216                         char *e;
217                         if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) ||
218                             ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) {
219                                 /* Skip EXPORT_SYMBOL{_GPL} */
220                                 while (isalnum(*p) || *p == '_')
221                                         p++;
222                                 /* Remove parentheses & additional whitespace */
223                                 while (isspace(*p))
224                                         p++;
225                                 if (*p != '(')
226                                         continue; /* Syntax error? */
227                                 else
228                                         p++;
229                                 while (isspace(*p))
230                                         p++;
231                                 e = p;
232                                 while (isalnum(*e) || *e == '_')
233                                         e++;
234                                 *e = '\0';
235                                 add_new_symbol(sym, p);
236                         }
237                 }
238                 fclose(fp);
239         }
240 }
241
242 /*
243  * Document all external or internal functions in a file.
244  * Call kernel-doc with following parameters:
245  * kernel-doc -docbook -nofunction function_name1 filename
246  * Function names are obtained from all the src files
247  * by find_export_symbols.
248  * intfunc uses -nofunction
249  * extfunc uses -function
250  */
251 static void docfunctions(char * filename, char * type)
252 {
253         int i,j;
254         int symcnt = 0;
255         int idx = 0;
256         char **vec;
257
258         for (i=0; i <= symfilecnt; i++)
259                 symcnt += symfilelist[i].symbolcnt;
260         vec = malloc((2 + 2 * symcnt + 3) * sizeof(char *));
261         if (vec == NULL) {
262                 perror("docproc: ");
263                 exit(1);
264         }
265         vec[idx++] = KERNELDOC;
266         vec[idx++] = DOCBOOK;
267         vec[idx++] = NODOCSECTIONS;
268         for (i=0; i < symfilecnt; i++) {
269                 struct symfile * sym = &symfilelist[i];
270                 for (j=0; j < sym->symbolcnt; j++) {
271                         vec[idx++]     = type;
272                         consume_symbol(sym->symbollist[j].name);
273                         vec[idx++] = sym->symbollist[j].name;
274                 }
275         }
276         vec[idx++]     = filename;
277         vec[idx] = NULL;
278         printf("<!-- %s -->\n", filename);
279         exec_kernel_doc(vec);
280         fflush(stdout);
281         free(vec);
282 }
283 static void intfunc(char * filename) {  docfunctions(filename, NOFUNCTION); }
284 static void extfunc(char * filename) { docfunctions(filename, FUNCTION);   }
285
286 /*
287  * Document specific function(s) in a file.
288  * Call kernel-doc with the following parameters:
289  * kernel-doc -docbook -function function1 [-function function2]
290  */
291 static void singfunc(char * filename, char * line)
292 {
293         char *vec[200]; /* Enough for specific functions */
294         int i, idx = 0;
295         int startofsym = 1;
296         vec[idx++] = KERNELDOC;
297         vec[idx++] = DOCBOOK;
298
299         /* Split line up in individual parameters preceded by FUNCTION */
300         for (i=0; line[i]; i++) {
301                 if (isspace(line[i])) {
302                         line[i] = '\0';
303                         startofsym = 1;
304                         continue;
305                 }
306                 if (startofsym) {
307                         startofsym = 0;
308                         vec[idx++] = FUNCTION;
309                         vec[idx++] = &line[i];
310                 }
311         }
312         for (i = 0; i < idx; i++) {
313                 if (strcmp(vec[i], FUNCTION))
314                         continue;
315                 consume_symbol(vec[i + 1]);
316         }
317         vec[idx++] = filename;
318         vec[idx] = NULL;
319         exec_kernel_doc(vec);
320 }
321
322 /*
323  * Insert specific documentation section from a file.
324  * Call kernel-doc with the following parameters:
325  * kernel-doc -docbook -function "doc section" filename
326  */
327 static void docsect(char *filename, char *line)
328 {
329         char *vec[6]; /* kerneldoc -docbook -function "section" file NULL */
330         char *s;
331
332         for (s = line; *s; s++)
333                 if (*s == '\n')
334                         *s = '\0';
335
336         if (asprintf(&s, "DOC: %s", line) < 0) {
337                 perror("asprintf");
338                 exit(1);
339         }
340         consume_symbol(s);
341         free(s);
342
343         vec[0] = KERNELDOC;
344         vec[1] = DOCBOOK;
345         vec[2] = FUNCTION;
346         vec[3] = line;
347         vec[4] = filename;
348         vec[5] = NULL;
349         exec_kernel_doc(vec);
350 }
351
352 static void find_all_symbols(char *filename)
353 {
354         char *vec[4]; /* kerneldoc -list file NULL */
355         pid_t pid;
356         int ret, i, count, start;
357         char real_filename[PATH_MAX + 1];
358         int pipefd[2];
359         char *data, *str;
360         size_t data_len = 0;
361
362         vec[0] = KERNELDOC;
363         vec[1] = LIST;
364         vec[2] = filename;
365         vec[3] = NULL;
366
367         if (pipe(pipefd)) {
368                 perror("pipe");
369                 exit(1);
370         }
371
372         switch (pid=fork()) {
373                 case -1:
374                         perror("fork");
375                         exit(1);
376                 case  0:
377                         close(pipefd[0]);
378                         dup2(pipefd[1], 1);
379                         memset(real_filename, 0, sizeof(real_filename));
380                         strncat(real_filename, kernsrctree, PATH_MAX);
381                         strncat(real_filename, "/" KERNELDOCPATH KERNELDOC,
382                                         PATH_MAX - strlen(real_filename));
383                         execvp(real_filename, vec);
384                         fprintf(stderr, "exec ");
385                         perror(real_filename);
386                         exit(1);
387                 default:
388                         close(pipefd[1]);
389                         data = malloc(4096);
390                         do {
391                                 while ((ret = read(pipefd[0],
392                                                    data + data_len,
393                                                    4096)) > 0) {
394                                         data_len += ret;
395                                         data = realloc(data, data_len + 4096);
396                                 }
397                         } while (ret == -EAGAIN);
398                         if (ret != 0) {
399                                 perror("read");
400                                 exit(1);
401                         }
402                         waitpid(pid, &ret ,0);
403         }
404         if (WIFEXITED(ret))
405                 exitstatus |= WEXITSTATUS(ret);
406         else
407                 exitstatus = 0xff;
408
409         count = 0;
410         /* poor man's strtok, but with counting */
411         for (i = 0; i < data_len; i++) {
412                 if (data[i] == '\n') {
413                         count++;
414                         data[i] = '\0';
415                 }
416         }
417         start = all_list_len;
418         all_list_len += count;
419         all_list = realloc(all_list, sizeof(char *) * all_list_len);
420         str = data;
421         for (i = 0; i < data_len && start != all_list_len; i++) {
422                 if (data[i] == '\0') {
423                         all_list[start] = str;
424                         str = data + i + 1;
425                         start++;
426                 }
427         }
428 }
429
430 /*
431  * Parse file, calling action specific functions for:
432  * 1) Lines containing !E
433  * 2) Lines containing !I
434  * 3) Lines containing !D
435  * 4) Lines containing !F
436  * 5) Lines containing !P
437  * 6) Lines containing !C
438  * 7) Default lines - lines not matching the above
439  */
440 static void parse_file(FILE *infile)
441 {
442         char line[MAXLINESZ];
443         char * s;
444         while (fgets(line, MAXLINESZ, infile)) {
445                 if (line[0] == '!') {
446                         s = line + 2;
447                         switch (line[1]) {
448                                 case 'E':
449                                         while (*s && !isspace(*s)) s++;
450                                         *s = '\0';
451                                         externalfunctions(line+2);
452                                         break;
453                                 case 'I':
454                                         while (*s && !isspace(*s)) s++;
455                                         *s = '\0';
456                                         internalfunctions(line+2);
457                                         break;
458                                 case 'D':
459                                         while (*s && !isspace(*s)) s++;
460                                         *s = '\0';
461                                         symbolsonly(line+2);
462                                         break;
463                                 case 'F':
464                                         /* filename */
465                                         while (*s && !isspace(*s)) s++;
466                                         *s++ = '\0';
467                                         /* function names */
468                                         while (isspace(*s))
469                                                 s++;
470                                         singlefunctions(line +2, s);
471                                         break;
472                                 case 'P':
473                                         /* filename */
474                                         while (*s && !isspace(*s)) s++;
475                                         *s++ = '\0';
476                                         /* DOC: section name */
477                                         while (isspace(*s))
478                                                 s++;
479                                         docsection(line + 2, s);
480                                         break;
481                                 case 'C':
482                                         while (*s && !isspace(*s)) s++;
483                                         *s = '\0';
484                                         if (findall)
485                                                 findall(line+2);
486                                         break;
487                                 default:
488                                         defaultline(line);
489                         }
490                 }
491                 else {
492                         defaultline(line);
493                 }
494         }
495         fflush(stdout);
496 }
497
498
499 int main(int argc, char *argv[])
500 {
501         FILE * infile;
502         int i;
503
504         srctree = getenv("SRCTREE");
505         if (!srctree)
506                 srctree = getcwd(NULL, 0);
507         kernsrctree = getenv("KBUILD_SRC");
508         if (!kernsrctree || !*kernsrctree)
509                 kernsrctree = srctree;
510         if (argc != 3) {
511                 usage();
512                 exit(1);
513         }
514         /* Open file, exit on error */
515         infile = fopen(argv[2], "r");
516         if (infile == NULL) {
517                 fprintf(stderr, "docproc: ");
518                 perror(argv[2]);
519                 exit(2);
520         }
521
522         if (strcmp("doc", argv[1]) == 0)
523         {
524                 /* Need to do this in two passes.
525                  * First pass is used to collect all symbols exported
526                  * in the various files;
527                  * Second pass generate the documentation.
528                  * This is required because some functions are declared
529                  * and exported in different files :-((
530                  */
531                 /* Collect symbols */
532                 defaultline       = noaction;
533                 internalfunctions = find_export_symbols;
534                 externalfunctions = find_export_symbols;
535                 symbolsonly       = find_export_symbols;
536                 singlefunctions   = noaction2;
537                 docsection        = noaction2;
538                 findall           = find_all_symbols;
539                 parse_file(infile);
540
541                 /* Rewind to start from beginning of file again */
542                 fseek(infile, 0, SEEK_SET);
543                 defaultline       = printline;
544                 internalfunctions = intfunc;
545                 externalfunctions = extfunc;
546                 symbolsonly       = printline;
547                 singlefunctions   = singfunc;
548                 docsection        = docsect;
549                 findall           = NULL;
550
551                 parse_file(infile);
552
553                 for (i = 0; i < all_list_len; i++) {
554                         if (!all_list[i])
555                                 continue;
556                         fprintf(stderr, "Warning: didn't use docs for %s\n",
557                                 all_list[i]);
558                 }
559         }
560         else if (strcmp("depend", argv[1]) == 0)
561         {
562                 /* Create first part of dependency chain
563                  * file.tmpl */
564                 printf("%s\t", argv[2]);
565                 defaultline       = noaction;
566                 internalfunctions = adddep;
567                 externalfunctions = adddep;
568                 symbolsonly       = adddep;
569                 singlefunctions   = adddep2;
570                 docsection        = adddep2;
571                 findall           = adddep;
572                 parse_file(infile);
573                 printf("\n");
574         }
575         else
576         {
577                 fprintf(stderr, "Unknown option: %s\n", argv[1]);
578                 exit(1);
579         }
580         fclose(infile);
581         fflush(stdout);
582         return exitstatus;
583 }