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                         fprintf(stderr, "docproc: ");
 210                         perror(real_filename);
 211                         exit(1);
 212                 }
 213                 while (fgets(line, MAXLINESZ, fp)) {
 214                         char *p;
 215                         char *e;
 216                         if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) ||
 217                             ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) {
 218                                 /* Skip EXPORT_SYMBOL{_GPL} */
 219                                 while (isalnum(*p) || *p == '_')
 220                                         p++;
 221                                 /* Remove parentheses & additional whitespace */
 222                                 while (isspace(*p))
 223                                         p++;
 224                                 if (*p != '(')
 225                                         continue; /* Syntax error? */
 226                                 else
 227                                         p++;
 228                                 while (isspace(*p))
 229                                         p++;
 230                                 e = p;
 231                                 while (isalnum(*e) || *e == '_')
 232                                         e++;
 233                                 *e = '\0';
 234                                 add_new_symbol(sym, p);
 235                         }
 236                 }
 237                 fclose(fp);
 238         }
 239 }
 240
 241 /*
 242  * Document all external or internal functions in a file.
 243  * Call kernel-doc with following parameters:
 244  * kernel-doc -docbook -nofunction function_name1 filename
 245  * Function names are obtained from all the src files
 246  * by find_export_symbols.
 247  * intfunc uses -nofunction
 248  * extfunc uses -function
 249  */
 250 static void docfunctions(char * filename, char * type)
 251 {
 252         int i,j;
 253         int symcnt = 0;
 254         int idx = 0;
 255         char **vec;
 256
 257         for (i=0; i <= symfilecnt; i++)
 258                 symcnt += symfilelist[i].symbolcnt;
 259         vec = malloc((2 + 2 * symcnt + 3) * sizeof(char *));
 260         if (vec == NULL) {
 261                 perror("docproc: ");
 262                 exit(1);
 263         }
 264         vec[idx++] = KERNELDOC;
 265         vec[idx++] = DOCBOOK;
 266         vec[idx++] = NODOCSECTIONS;
 267         for (i=0; i < symfilecnt; i++) {
 268                 struct symfile * sym = &symfilelist[i];
 269                 for (j=0; j < sym->symbolcnt; j++) {
 270                         vec[idx++]     = type;
 271                         consume_symbol(sym->symbollist[j].name);
 272                         vec[idx++] = sym->symbollist[j].name;
 273                 }
 274         }
 275         vec[idx++]     = filename;
 276         vec[idx] = NULL;
 277         printf("<!-- %s -->\n", filename);
 278         exec_kernel_doc(vec);
 279         fflush(stdout);
 280         free(vec);
 281 }
 282 static void intfunc(char * filename) {  docfunctions(filename, NOFUNCTION); }
 283 static void extfunc(char * filename) { docfunctions(filename, FUNCTION);   }
 284
 285 /*
 286  * Document specific function(s) in a file.
 287  * Call kernel-doc with the following parameters:
 288  * kernel-doc -docbook -function function1 [-function function2]
 289  */
 290 static void singfunc(char * filename, char * line)
 291 {
 292         char *vec[200]; /* Enough for specific functions */
 293         int i, idx = 0;
 294         int startofsym = 1;
 295         vec[idx++] = KERNELDOC;
 296         vec[idx++] = DOCBOOK;
 297
 298         /* Split line up in individual parameters preceded by FUNCTION */
 299         for (i=0; line[i]; i++) {
 300                 if (isspace(line[i])) {
 301                         line[i] = '\0';
 302                         startofsym = 1;
 303                         continue;
 304                 }
 305                 if (startofsym) {
 306                         startofsym = 0;
 307                         vec[idx++] = FUNCTION;
 308                         vec[idx++] = &line[i];
 309                 }
 310         }
 311         for (i = 0; i < idx; i++) {
 312                 if (strcmp(vec[i], FUNCTION))
 313                         continue;
 314                 consume_symbol(vec[i + 1]);
 315         }
 316         vec[idx++] = filename;
 317         vec[idx] = NULL;
 318         exec_kernel_doc(vec);
 319 }
 320
 321 /*
 322  * Insert specific documentation section from a file.
 323  * Call kernel-doc with the following parameters:
 324  * kernel-doc -docbook -function "doc section" filename
 325  */
 326 static void docsect(char *filename, char *line)
 327 {
 328         char *vec[6]; /* kerneldoc -docbook -function "section" file NULL */
 329         char *s;
 330
 331         for (s = line; *s; s++)
 332                 if (*s == '\n')
 333                         *s = '\0';
 334
 335         if (asprintf(&s, "DOC: %s", line) < 0) {
 336                 perror("asprintf");
 337                 exit(1);
 338         }
 339         consume_symbol(s);
 340         free(s);
 341
 342         vec[0] = KERNELDOC;
 343         vec[1] = DOCBOOK;
 344         vec[2] = FUNCTION;
 345         vec[3] = line;
 346         vec[4] = filename;
 347         vec[5] = NULL;
 348         exec_kernel_doc(vec);
 349 }
 350
 351 static void find_all_symbols(char *filename)
 352 {
 353         char *vec[4]; /* kerneldoc -list file NULL */
 354         pid_t pid;
 355         int ret, i, count, start;
 356         char real_filename[PATH_MAX + 1];
 357         int pipefd[2];
 358         char *data, *str;
 359         size_t data_len = 0;
 360
 361         vec[0] = KERNELDOC;
 362         vec[1] = LIST;
 363         vec[2] = filename;
 364         vec[3] = NULL;
 365
 366         if (pipe(pipefd)) {
 367                 perror("pipe");
 368                 exit(1);
 369         }
 370
 371         switch (pid=fork()) {
 372                 case -1:
 373                         perror("fork");
 374                         exit(1);
 375                 case  0:
 376                         close(pipefd[0]);
 377                         dup2(pipefd[1], 1);
 378                         memset(real_filename, 0, sizeof(real_filename));
 379                         strncat(real_filename, kernsrctree, PATH_MAX);
 380                         strncat(real_filename, "/" KERNELDOCPATH KERNELDOC,
 381                                         PATH_MAX - strlen(real_filename));
 382                         execvp(real_filename, vec);
 383                         fprintf(stderr, "exec ");
 384                         perror(real_filename);
 385                         exit(1);
 386                 default:
 387                         close(pipefd[1]);
 388                         data = malloc(4096);
 389                         do {
 390                                 while ((ret = read(pipefd[0],
 391                                                    data + data_len,
 392                                                    4096)) > 0) {
 393                                         data_len += ret;
 394                                         data = realloc(data, data_len + 4096);
 395                                 }
 396                         } while (ret == -EAGAIN);
 397                         if (ret != 0) {
 398                                 perror("read");
 399                                 exit(1);
 400                         }
 401                         waitpid(pid, &ret ,0);
 402         }
 403         if (WIFEXITED(ret))
 404                 exitstatus |= WEXITSTATUS(ret);
 405         else
 406                 exitstatus = 0xff;
 407
 408         count = 0;
 409         /* poor man's strtok, but with counting */
 410         for (i = 0; i < data_len; i++) {
 411                 if (data[i] == '\n') {
 412                         count++;
 413                         data[i] = '\0';
 414                 }
 415         }
 416         start = all_list_len;
 417         all_list_len += count;
 418         all_list = realloc(all_list, sizeof(char *) * all_list_len);
 419         str = data;
 420         for (i = 0; i < data_len && start != all_list_len; i++) {
 421                 if (data[i] == '\0') {
 422                         all_list[start] = str;
 423                         str = data + i + 1;
 424                         start++;
 425                 }
 426         }
 427 }
 428
 429 /*
 430  * Parse file, calling action specific functions for:
 431  * 1) Lines containing !E
 432  * 2) Lines containing !I
 433  * 3) Lines containing !D
 434  * 4) Lines containing !F
 435  * 5) Lines containing !P
 436  * 6) Lines containing !C
 437  * 7) Default lines - lines not matching the above
 438  */
 439 static void parse_file(FILE *infile)
 440 {
 441         char line[MAXLINESZ];
 442         char * s;
 443         while (fgets(line, MAXLINESZ, infile)) {
 444                 if (line[0] == '!') {
 445                         s = line + 2;
 446                         switch (line[1]) {
 447                                 case 'E':
 448                                         while (*s && !isspace(*s)) s++;
 449                                         *s = '\0';
 450                                         externalfunctions(line+2);
 451                                         break;
 452                                 case 'I':
 453                                         while (*s && !isspace(*s)) s++;
 454                                         *s = '\0';
 455                                         internalfunctions(line+2);
 456                                         break;
 457                                 case 'D':
 458                                         while (*s && !isspace(*s)) s++;
 459                                         *s = '\0';
 460                                         symbolsonly(line+2);
 461                                         break;
 462                                 case 'F':
 463                                         /* filename */
 464                                         while (*s && !isspace(*s)) s++;
 465                                         *s++ = '\0';
 466                                         /* function names */
 467                                         while (isspace(*s))
 468                                                 s++;
 469                                         singlefunctions(line +2, s);
 470                                         break;
 471                                 case 'P':
 472                                         /* filename */
 473                                         while (*s && !isspace(*s)) s++;
 474                                         *s++ = '\0';
 475                                         /* DOC: section name */
 476                                         while (isspace(*s))
 477                                                 s++;
 478                                         docsection(line + 2, s);
 479                                         break;
 480                                 case 'C':
 481                                         while (*s && !isspace(*s)) s++;
 482                                         *s = '\0';
 483                                         if (findall)
 484                                                 findall(line+2);
 485                                         break;
 486                                 default:
 487                                         defaultline(line);
 488                         }
 489                 } else {
 490                         defaultline(line);
 491                 }
 492         }
 493         fflush(stdout);
 494 }
 495
 496
 497 int main(int argc, char *argv[])
 498 {
 499         FILE * infile;
 500         int i;
 501
 502         srctree = getenv("SRCTREE");
 503         if (!srctree)
 504                 srctree = getcwd(NULL, 0);
 505         kernsrctree = getenv("KBUILD_SRC");
 506         if (!kernsrctree || !*kernsrctree)
 507                 kernsrctree = srctree;
 508         if (argc != 3) {
 509                 usage();
 510                 exit(1);
 511         }
 512         /* Open file, exit on error */
 513         infile = fopen(argv[2], "r");
 514         if (infile == NULL) {
 515                 fprintf(stderr, "docproc: ");
 516                 perror(argv[2]);
 517                 exit(2);
 518         }
 519
 520         if (strcmp("doc", argv[1]) == 0) {
 521                 /* Need to do this in two passes.
 522                  * First pass is used to collect all symbols exported
 523                  * in the various files;
 524                  * Second pass generate the documentation.
 525                  * This is required because some functions are declared
 526                  * and exported in different files :-((
 527                  */
 528                 /* Collect symbols */
 529                 defaultline       = noaction;
 530                 internalfunctions = find_export_symbols;
 531                 externalfunctions = find_export_symbols;
 532                 symbolsonly       = find_export_symbols;
 533                 singlefunctions   = noaction2;
 534                 docsection        = noaction2;
 535                 findall           = find_all_symbols;
 536                 parse_file(infile);
 537
 538                 /* Rewind to start from beginning of file again */
 539                 fseek(infile, 0, SEEK_SET);
 540                 defaultline       = printline;
 541                 internalfunctions = intfunc;
 542                 externalfunctions = extfunc;
 543                 symbolsonly       = printline;
 544                 singlefunctions   = singfunc;
 545                 docsection        = docsect;
 546                 findall           = NULL;
 547
 548                 parse_file(infile);
 549
 550                 for (i = 0; i < all_list_len; i++) {
 551                         if (!all_list[i])
 552                                 continue;
 553                         fprintf(stderr, "Warning: didn't use docs for %s\n",
 554                                 all_list[i]);
 555                 }
 556         } else if (strcmp("depend", argv[1]) == 0) {
 557                 /* Create first part of dependency chain
 558                  * file.tmpl */
 559                 printf("%s\t", argv[2]);
 560                 defaultline       = noaction;
 561                 internalfunctions = adddep;
 562                 externalfunctions = adddep;
 563                 symbolsonly       = adddep;
 564                 singlefunctions   = adddep2;
 565                 docsection        = adddep2;
 566                 findall           = adddep;
 567                 parse_file(infile);
 568                 printf("\n");
 569         } else {
 570                 fprintf(stderr, "Unknown option: %s\n", argv[1]);
 571                 exit(1);
 572         }
 573         fclose(infile);
 574         fflush(stdout);
 575         return exitstatus;
 576 }