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 }