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 static 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 static 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 static 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 static 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 static 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 static void adddep(char * file)            { printf("\t%s", file); }
 161 static void adddep2(char * file, char * line)     { line = line; adddep(file); }
 162 static void noaction(char * line)                  { line = line; }
 163 static void noaction2(char * file, char * line)   { file = file; line = line; }
 164
 165 /* Echo the line without further action */
 166 static 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 static 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 static 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 static void intfunc(char * filename) {  docfunctions(filename, NOFUNCTION); }
 262 static 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 static 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 static 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 static 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 }