kbuild: fix build error during make htmldocs
[linux-2.6.git] / scripts / basic / 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 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <ctype.h>
41 #include <unistd.h>
42 #include <limits.h>
43 #include <sys/types.h>
44 #include <sys/wait.h>
45
46 /* exitstatus is used to keep track of any failing calls to kernel-doc,
47  * but execution continues. */
48 int exitstatus = 0;
49
50 typedef void DFL(char *);
51 DFL *defaultline;
52
53 typedef void FILEONLY(char * file);
54 FILEONLY *internalfunctions;
55 FILEONLY *externalfunctions;
56 FILEONLY *symbolsonly;
57
58 typedef void FILELINE(char * file, char * line);
59 FILELINE * singlefunctions;
60 FILELINE * entity_system;
61 FILELINE * docsection;
62
63 #define MAXLINESZ     2048
64 #define MAXFILES      250
65 #define KERNELDOCPATH "scripts/"
66 #define KERNELDOC     "kernel-doc"
67 #define DOCBOOK       "-docbook"
68 #define FUNCTION      "-function"
69 #define NOFUNCTION    "-nofunction"
70 #define NODOCSECTIONS "-no-doc-sections"
71
72 static char *srctree, *kernsrctree;
73
74 void usage (void)
75 {
76         fprintf(stderr, "Usage: docproc {doc|depend} file\n");
77         fprintf(stderr, "Input is read from file.tmpl. Output is sent to stdout\n");
78         fprintf(stderr, "doc: frontend when generating kernel documentation\n");
79         fprintf(stderr, "depend: generate list of files referenced within file\n");
80         fprintf(stderr, "Environment variable SRCTREE: absolute path to sources.\n");
81         fprintf(stderr, "                     KBUILD_SRC: absolute path to kernel source tree.\n");
82 }
83
84 /*
85  * Execute kernel-doc with parameters given in svec
86  */
87 void exec_kernel_doc(char **svec)
88 {
89         pid_t pid;
90         int ret;
91         char real_filename[PATH_MAX + 1];
92         /* Make sure output generated so far are flushed */
93         fflush(stdout);
94         switch (pid=fork()) {
95                 case -1:
96                         perror("fork");
97                         exit(1);
98                 case  0:
99                         memset(real_filename, 0, sizeof(real_filename));
100                         strncat(real_filename, kernsrctree, PATH_MAX);
101                         strncat(real_filename, "/" KERNELDOCPATH KERNELDOC,
102                                         PATH_MAX - strlen(real_filename));
103                         execvp(real_filename, svec);
104                         fprintf(stderr, "exec ");
105                         perror(real_filename);
106                         exit(1);
107                 default:
108                         waitpid(pid, &ret ,0);
109         }
110         if (WIFEXITED(ret))
111                 exitstatus |= WEXITSTATUS(ret);
112         else
113                 exitstatus = 0xff;
114 }
115
116 /* Types used to create list of all exported symbols in a number of files */
117 struct symbols
118 {
119         char *name;
120 };
121
122 struct symfile
123 {
124         char *filename;
125         struct symbols *symbollist;
126         int symbolcnt;
127 };
128
129 struct symfile symfilelist[MAXFILES];
130 int symfilecnt = 0;
131
132 void add_new_symbol(struct symfile *sym, char * symname)
133 {
134         sym->symbollist =
135           realloc(sym->symbollist, (sym->symbolcnt + 1) * sizeof(char *));
136         sym->symbollist[sym->symbolcnt++].name = strdup(symname);
137 }
138
139 /* Add a filename to the list */
140 struct symfile * add_new_file(char * filename)
141 {
142         symfilelist[symfilecnt++].filename = strdup(filename);
143         return &symfilelist[symfilecnt - 1];
144 }
145
146 /* Check if file already are present in the list */
147 struct symfile * filename_exist(char * filename)
148 {
149         int i;
150         for (i=0; i < symfilecnt; i++)
151                 if (strcmp(symfilelist[i].filename, filename) == 0)
152                         return &symfilelist[i];
153         return NULL;
154 }
155
156 /*
157  * List all files referenced within the template file.
158  * Files are separated by tabs.
159  */
160 void adddep(char * file)                   { printf("\t%s", file); }
161 void adddep2(char * file, char * line)     { line = line; adddep(file); }
162 void noaction(char * line)                 { line = line; }
163 void noaction2(char * file, char * line)   { file = file; line = line; }
164
165 /* Echo the line without further action */
166 void printline(char * line)               { printf("%s", line); }
167
168 /*
169  * Find all symbols in filename that are exported with EXPORT_SYMBOL &
170  * EXPORT_SYMBOL_GPL (& EXPORT_SYMBOL_GPL_FUTURE implicitly).
171  * All symbols located are stored in symfilelist.
172  */
173 void find_export_symbols(char * filename)
174 {
175         FILE * fp;
176         struct symfile *sym;
177         char line[MAXLINESZ];
178         if (filename_exist(filename) == NULL) {
179                 char real_filename[PATH_MAX + 1];
180                 memset(real_filename, 0, sizeof(real_filename));
181                 strncat(real_filename, srctree, PATH_MAX);
182                 strncat(real_filename, "/", PATH_MAX - strlen(real_filename));
183                 strncat(real_filename, filename,
184                                 PATH_MAX - strlen(real_filename));
185                 sym = add_new_file(filename);
186                 fp = fopen(real_filename, "r");
187                 if (fp == NULL)
188                 {
189                         fprintf(stderr, "docproc: ");
190                         perror(real_filename);
191                         exit(1);
192                 }
193                 while (fgets(line, MAXLINESZ, fp)) {
194                         char *p;
195                         char *e;
196                         if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) ||
197                             ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) {
198                                 /* Skip EXPORT_SYMBOL{_GPL} */
199                                 while (isalnum(*p) || *p == '_')
200                                         p++;
201                                 /* Remove parentheses & additional whitespace */
202                                 while (isspace(*p))
203                                         p++;
204                                 if (*p != '(')
205                                         continue; /* Syntax error? */
206                                 else
207                                         p++;
208                                 while (isspace(*p))
209                                         p++;
210                                 e = p;
211                                 while (isalnum(*e) || *e == '_')
212                                         e++;
213                                 *e = '\0';
214                                 add_new_symbol(sym, p);
215                         }
216                 }
217                 fclose(fp);
218         }
219 }
220
221 /*
222  * Document all external or internal functions in a file.
223  * Call kernel-doc with following parameters:
224  * kernel-doc -docbook -nofunction function_name1 filename
225  * Function names are obtained from all the src files
226  * by find_export_symbols.
227  * intfunc uses -nofunction
228  * extfunc uses -function
229  */
230 void docfunctions(char * filename, char * type)
231 {
232         int i,j;
233         int symcnt = 0;
234         int idx = 0;
235         char **vec;
236
237         for (i=0; i <= symfilecnt; i++)
238                 symcnt += symfilelist[i].symbolcnt;
239         vec = malloc((2 + 2 * symcnt + 3) * sizeof(char *));
240         if (vec == NULL) {
241                 perror("docproc: ");
242                 exit(1);
243         }
244         vec[idx++] = KERNELDOC;
245         vec[idx++] = DOCBOOK;
246         vec[idx++] = NODOCSECTIONS;
247         for (i=0; i < symfilecnt; i++) {
248                 struct symfile * sym = &symfilelist[i];
249                 for (j=0; j < sym->symbolcnt; j++) {
250                         vec[idx++]     = type;
251                         vec[idx++] = sym->symbollist[j].name;
252                 }
253         }
254         vec[idx++]     = filename;
255         vec[idx] = NULL;
256         printf("<!-- %s -->\n", filename);
257         exec_kernel_doc(vec);
258         fflush(stdout);
259         free(vec);
260 }
261 void intfunc(char * filename) { docfunctions(filename, NOFUNCTION); }
262 void extfunc(char * filename) { docfunctions(filename, FUNCTION);   }
263
264 /*
265  * Document specific function(s) in a file.
266  * Call kernel-doc with the following parameters:
267  * kernel-doc -docbook -function function1 [-function function2]
268  */
269 void singfunc(char * filename, char * line)
270 {
271         char *vec[200]; /* Enough for specific functions */
272         int i, idx = 0;
273         int startofsym = 1;
274         vec[idx++] = KERNELDOC;
275         vec[idx++] = DOCBOOK;
276
277         /* Split line up in individual parameters preceded by FUNCTION */
278         for (i=0; line[i]; i++) {
279                 if (isspace(line[i])) {
280                         line[i] = '\0';
281                         startofsym = 1;
282                         continue;
283                 }
284                 if (startofsym) {
285                         startofsym = 0;
286                         vec[idx++] = FUNCTION;
287                         vec[idx++] = &line[i];
288                 }
289         }
290         vec[idx++] = filename;
291         vec[idx] = NULL;
292         exec_kernel_doc(vec);
293 }
294
295 /*
296  * Insert specific documentation section from a file.
297  * Call kernel-doc with the following parameters:
298  * kernel-doc -docbook -function "doc section" filename
299  */
300 void docsect(char *filename, char *line)
301 {
302         char *vec[6]; /* kerneldoc -docbook -function "section" file NULL */
303         char *s;
304
305         for (s = line; *s; s++)
306                 if (*s == '\n')
307                         *s = '\0';
308
309         vec[0] = KERNELDOC;
310         vec[1] = DOCBOOK;
311         vec[2] = FUNCTION;
312         vec[3] = line;
313         vec[4] = filename;
314         vec[5] = NULL;
315         exec_kernel_doc(vec);
316 }
317
318 /*
319  * Parse file, calling action specific functions for:
320  * 1) Lines containing !E
321  * 2) Lines containing !I
322  * 3) Lines containing !D
323  * 4) Lines containing !F
324  * 5) Lines containing !P
325  * 6) Default lines - lines not matching the above
326  */
327 void parse_file(FILE *infile)
328 {
329         char line[MAXLINESZ];
330         char * s;
331         while (fgets(line, MAXLINESZ, infile)) {
332                 if (line[0] == '!') {
333                         s = line + 2;
334                         switch (line[1]) {
335                                 case 'E':
336                                         while (*s && !isspace(*s)) s++;
337                                         *s = '\0';
338                                         externalfunctions(line+2);
339                                         break;
340                                 case 'I':
341                                         while (*s && !isspace(*s)) s++;
342                                         *s = '\0';
343                                         internalfunctions(line+2);
344                                         break;
345                                 case 'D':
346                                         while (*s && !isspace(*s)) s++;
347                                         *s = '\0';
348                                         symbolsonly(line+2);
349                                         break;
350                                 case 'F':
351                                         /* filename */
352                                         while (*s && !isspace(*s)) s++;
353                                         *s++ = '\0';
354                                         /* function names */
355                                         while (isspace(*s))
356                                                 s++;
357                                         singlefunctions(line +2, s);
358                                         break;
359                                 case 'P':
360                                         /* filename */
361                                         while (*s && !isspace(*s)) s++;
362                                         *s++ = '\0';
363                                         /* DOC: section name */
364                                         while (isspace(*s))
365                                                 s++;
366                                         docsection(line + 2, s);
367                                         break;
368                                 default:
369                                         defaultline(line);
370                         }
371                 }
372                 else {
373                         defaultline(line);
374                 }
375         }
376         fflush(stdout);
377 }
378
379
380 int main(int argc, char *argv[])
381 {
382         FILE * infile;
383
384         srctree = getenv("SRCTREE");
385         if (!srctree)
386                 srctree = getcwd(NULL, 0);
387         kernsrctree = getenv("KBUILD_SRC");
388         if (!kernsrctree || !*kernsrctree)
389                 kernsrctree = srctree;
390         if (argc != 3) {
391                 usage();
392                 exit(1);
393         }
394         /* Open file, exit on error */
395         infile = fopen(argv[2], "r");
396         if (infile == NULL) {
397                 fprintf(stderr, "docproc: ");
398                 perror(argv[2]);
399                 exit(2);
400         }
401
402         if (strcmp("doc", argv[1]) == 0)
403         {
404                 /* Need to do this in two passes.
405                  * First pass is used to collect all symbols exported
406                  * in the various files;
407                  * Second pass generate the documentation.
408                  * This is required because some functions are declared
409                  * and exported in different files :-((
410                  */
411                 /* Collect symbols */
412                 defaultline       = noaction;
413                 internalfunctions = find_export_symbols;
414                 externalfunctions = find_export_symbols;
415                 symbolsonly       = find_export_symbols;
416                 singlefunctions   = noaction2;
417                 docsection        = noaction2;
418                 parse_file(infile);
419
420                 /* Rewind to start from beginning of file again */
421                 fseek(infile, 0, SEEK_SET);
422                 defaultline       = printline;
423                 internalfunctions = intfunc;
424                 externalfunctions = extfunc;
425                 symbolsonly       = printline;
426                 singlefunctions   = singfunc;
427                 docsection        = docsect;
428
429                 parse_file(infile);
430         }
431         else if (strcmp("depend", argv[1]) == 0)
432         {
433                 /* Create first part of dependency chain
434                  * file.tmpl */
435                 printf("%s\t", argv[2]);
436                 defaultline       = noaction;
437                 internalfunctions = adddep;
438                 externalfunctions = adddep;
439                 symbolsonly       = adddep;
440                 singlefunctions   = adddep2;
441                 docsection        = adddep2;
442                 parse_file(infile);
443                 printf("\n");
444         }
445         else
446         {
447                 fprintf(stderr, "Unknown option: %s\n", argv[1]);
448                 exit(1);
449         }
450         fclose(infile);
451         fflush(stdout);
452         return exitstatus;
453 }