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  *
  34  */
  35
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <ctype.h>
  40 #include <unistd.h>
  41 #include <limits.h>
  42 #include <sys/types.h>
  43 #include <sys/wait.h>
  44
  45 /* exitstatus is used to keep track of any failing calls to kernel-doc,
  46  * but execution continues. */
  47 int exitstatus = 0;
  48
  49 typedef void DFL(char *);
  50 DFL *defaultline;
  51
  52 typedef void FILEONLY(char * file);
  53 FILEONLY *internalfunctions;
  54 FILEONLY *externalfunctions;
  55 FILEONLY *symbolsonly;
  56
  57 typedef void FILELINE(char * file, char * line);
  58 FILELINE * singlefunctions;
  59 FILELINE * entity_system;
  60
  61 #define MAXLINESZ     2048
  62 #define MAXFILES      250
  63 #define KERNELDOCPATH "scripts/"
  64 #define KERNELDOC     "kernel-doc"
  65 #define DOCBOOK       "-docbook"
  66 #define FUNCTION      "-function"
  67 #define NOFUNCTION    "-nofunction"
  68
  69 void usage (void)
  70 {
  71         fprintf(stderr, "Usage: docproc {doc|depend} file\n");
  72         fprintf(stderr, "Input is read from file.tmpl. Output is sent to stdout\n");
  73         fprintf(stderr, "doc: frontend when generating kernel documentation\n");
  74         fprintf(stderr, "depend: generate list of files referenced within file\n");
  75 }
  76
  77 /*
  78  * Execute kernel-doc with parameters given in svec
  79  */
  80 void exec_kernel_doc(char **svec)
  81 {
  82         pid_t pid;
  83         int ret;
  84         char real_filename[PATH_MAX + 1];
  85         /* Make sure output generated so far are flushed */
  86         fflush(stdout);
  87         switch (pid=fork()) {
  88                 case -1:
  89                         perror("fork");
  90                         exit(1);
  91                 case  0:
  92                         memset(real_filename, 0, sizeof(real_filename));
  93                         strncat(real_filename, getenv("SRCTREE"), PATH_MAX);
  94                         strncat(real_filename, KERNELDOCPATH KERNELDOC,
  95                                         PATH_MAX - strlen(real_filename));
  96                         execvp(real_filename, svec);
  97                         fprintf(stderr, "exec ");
  98                         perror(real_filename);
  99                         exit(1);
 100                 default:
 101                         waitpid(pid, &ret ,0);
 102         }
 103         if (WIFEXITED(ret))
 104                 exitstatus |= WEXITSTATUS(ret);
 105         else
 106                 exitstatus = 0xff;
 107 }
 108
 109 /* Types used to create list of all exported symbols in a number of files */
 110 struct symbols
 111 {
 112         char *name;
 113 };
 114
 115 struct symfile
 116 {
 117         char *filename;
 118         struct symbols *symbollist;
 119         int symbolcnt;
 120 };
 121
 122 struct symfile symfilelist[MAXFILES];
 123 int symfilecnt = 0;
 124
 125 void add_new_symbol(struct symfile *sym, char * symname)
 126 {
 127         sym->symbollist =
 128           realloc(sym->symbollist, (sym->symbolcnt + 1) * sizeof(char *));
 129         sym->symbollist[sym->symbolcnt++].name = strdup(symname);
 130 }
 131
 132 /* Add a filename to the list */
 133 struct symfile * add_new_file(char * filename)
 134 {
 135         symfilelist[symfilecnt++].filename = strdup(filename);
 136         return &symfilelist[symfilecnt - 1];
 137 }
 138
 139 /* Check if file already are present in the list */
 140 struct symfile * filename_exist(char * filename)
 141 {
 142         int i;
 143         for (i=0; i < symfilecnt; i++)
 144                 if (strcmp(symfilelist[i].filename, filename) == 0)
 145                         return &symfilelist[i];
 146         return NULL;
 147 }
 148
 149 /*
 150  * List all files referenced within the template file.
 151  * Files are separated by tabs.
 152  */
 153 void adddep(char * file)                   { printf("\t%s", file); }
 154 void adddep2(char * file, char * line)     { line = line; adddep(file); }
 155 void noaction(char * line)                 { line = line; }
 156 void noaction2(char * file, char * line)   { file = file; line = line; }
 157
 158 /* Echo the line without further action */
 159 void printline(char * line)               { printf("%s", line); }
 160
 161 /*
 162  * Find all symbols in filename that are exported with EXPORT_SYMBOL &
 163  * EXPORT_SYMBOL_GPL (& EXPORT_SYMBOL_GPL_FUTURE implicitly).
 164  * All symbols located are stored in symfilelist.
 165  */
 166 void find_export_symbols(char * filename)
 167 {
 168         FILE * fp;
 169         struct symfile *sym;
 170         char line[MAXLINESZ];
 171         if (filename_exist(filename) == NULL) {
 172                 char real_filename[PATH_MAX + 1];
 173                 memset(real_filename, 0, sizeof(real_filename));
 174                 strncat(real_filename, getenv("SRCTREE"), PATH_MAX);
 175                 strncat(real_filename, filename,
 176                                 PATH_MAX - strlen(real_filename));
 177                 sym = add_new_file(filename);
 178                 fp = fopen(real_filename, "r");
 179                 if (fp == NULL)
 180                 {
 181                         fprintf(stderr, "docproc: ");
 182                         perror(real_filename);
 183                         exit(1);
 184                 }
 185                 while (fgets(line, MAXLINESZ, fp)) {
 186                         char *p;
 187                         char *e;
 188                         if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) ||
 189                             ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) {
 190                                 /* Skip EXPORT_SYMBOL{_GPL} */
 191                                 while (isalnum(*p) || *p == '_')
 192                                         p++;
 193                                 /* Remove parentheses & additional whitespace */
 194                                 while (isspace(*p))
 195                                         p++;
 196                                 if (*p != '(')
 197                                         continue; /* Syntax error? */
 198                                 else
 199                                         p++;
 200                                 while (isspace(*p))
 201                                         p++;
 202                                 e = p;
 203                                 while (isalnum(*e) || *e == '_')
 204                                         e++;
 205                                 *e = '\0';
 206                                 add_new_symbol(sym, p);
 207                         }
 208                 }
 209                 fclose(fp);
 210         }
 211 }
 212
 213 /*
 214  * Document all external or internal functions in a file.
 215  * Call kernel-doc with following parameters:
 216  * kernel-doc -docbook -nofunction function_name1 filename
 217  * Function names are obtained from all the src files
 218  * by find_export_symbols.
 219  * intfunc uses -nofunction
 220  * extfunc uses -function
 221  */
 222 void docfunctions(char * filename, char * type)
 223 {
 224         int i,j;
 225         int symcnt = 0;
 226         int idx = 0;
 227         char **vec;
 228
 229         for (i=0; i <= symfilecnt; i++)
 230                 symcnt += symfilelist[i].symbolcnt;
 231         vec = malloc((2 + 2 * symcnt + 2) * sizeof(char*));
 232         if (vec == NULL) {
 233                 perror("docproc: ");
 234                 exit(1);
 235         }
 236         vec[idx++] = KERNELDOC;
 237         vec[idx++] = DOCBOOK;
 238         for (i=0; i < symfilecnt; i++) {
 239                 struct symfile * sym = &symfilelist[i];
 240                 for (j=0; j < sym->symbolcnt; j++) {
 241                         vec[idx++]     = type;
 242                         vec[idx++] = sym->symbollist[j].name;
 243                 }
 244         }
 245         vec[idx++]     = filename;
 246         vec[idx] = NULL;
 247         printf("<!-- %s -->\n", filename);
 248         exec_kernel_doc(vec);
 249         fflush(stdout);
 250         free(vec);
 251 }
 252 void intfunc(char * filename) { docfunctions(filename, NOFUNCTION); }
 253 void extfunc(char * filename) { docfunctions(filename, FUNCTION);   }
 254
 255 /*
 256  * Document specific function(s) in a file.
 257  * Call kernel-doc with the following parameters:
 258  * kernel-doc -docbook -function function1 [-function function2]
 259  */
 260 void singfunc(char * filename, char * line)
 261 {
 262         char *vec[200]; /* Enough for specific functions */
 263         int i, idx = 0;
 264         int startofsym = 1;
 265         vec[idx++] = KERNELDOC;
 266         vec[idx++] = DOCBOOK;
 267
 268         /* Split line up in individual parameters preceded by FUNCTION */
 269         for (i=0; line[i]; i++) {
 270                 if (isspace(line[i])) {
 271                         line[i] = '\0';
 272                         startofsym = 1;
 273                         continue;
 274                 }
 275                 if (startofsym) {
 276                         startofsym = 0;
 277                         vec[idx++] = FUNCTION;
 278                         vec[idx++] = &line[i];
 279                 }
 280         }
 281         vec[idx++] = filename;
 282         vec[idx] = NULL;
 283         exec_kernel_doc(vec);
 284 }
 285
 286 /*
 287  * Parse file, calling action specific functions for:
 288  * 1) Lines containing !E
 289  * 2) Lines containing !I
 290  * 3) Lines containing !D
 291  * 4) Lines containing !F
 292  * 5) Default lines - lines not matching the above
 293  */
 294 void parse_file(FILE *infile)
 295 {
 296         char line[MAXLINESZ];
 297         char * s;
 298         while (fgets(line, MAXLINESZ, infile)) {
 299                 if (line[0] == '!') {
 300                         s = line + 2;
 301                         switch (line[1]) {
 302                                 case 'E':
 303                                         while (*s && !isspace(*s)) s++;
 304                                         *s = '\0';
 305                                         externalfunctions(line+2);
 306                                         break;
 307                                 case 'I':
 308                                         while (*s && !isspace(*s)) s++;
 309                                         *s = '\0';
 310                                         internalfunctions(line+2);
 311                                         break;
 312                                 case 'D':
 313                                         while (*s && !isspace(*s)) s++;
 314                                         *s = '\0';
 315                                         symbolsonly(line+2);
 316                                         break;
 317                                 case 'F':
 318                                         /* filename */
 319                                         while (*s && !isspace(*s)) s++;
 320                                         *s++ = '\0';
 321                                         /* function names */
 322                                         while (isspace(*s))
 323                                                 s++;
 324                                         singlefunctions(line +2, s);
 325                                         break;
 326                                 default:
 327                                         defaultline(line);
 328                         }
 329                 }
 330                 else {
 331                         defaultline(line);
 332                 }
 333         }
 334         fflush(stdout);
 335 }
 336
 337
 338 int main(int argc, char *argv[])
 339 {
 340         FILE * infile;
 341         if (argc != 3) {
 342                 usage();
 343                 exit(1);
 344         }
 345         /* Open file, exit on error */
 346         infile = fopen(argv[2], "r");
 347         if (infile == NULL) {
 348                 fprintf(stderr, "docproc: ");
 349                 perror(argv[2]);
 350                 exit(2);
 351         }
 352
 353         if (strcmp("doc", argv[1]) == 0)
 354         {
 355                 /* Need to do this in two passes.
 356                  * First pass is used to collect all symbols exported
 357                  * in the various files;
 358                  * Second pass generate the documentation.
 359                  * This is required because some functions are declared
 360                  * and exported in different files :-((
 361                  */
 362                 /* Collect symbols */
 363                 defaultline       = noaction;
 364                 internalfunctions = find_export_symbols;
 365                 externalfunctions = find_export_symbols;
 366                 symbolsonly       = find_export_symbols;
 367                 singlefunctions   = noaction2;
 368                 parse_file(infile);
 369
 370                 /* Rewind to start from beginning of file again */
 371                 fseek(infile, 0, SEEK_SET);
 372                 defaultline       = printline;
 373                 internalfunctions = intfunc;
 374                 externalfunctions = extfunc;
 375                 symbolsonly       = printline;
 376                 singlefunctions   = singfunc;
 377
 378                 parse_file(infile);
 379         }
 380         else if (strcmp("depend", argv[1]) == 0)
 381         {
 382                 /* Create first part of dependency chain
 383                  * file.tmpl */
 384                 printf("%s\t", argv[2]);
 385                 defaultline       = noaction;
 386                 internalfunctions = adddep;
 387                 externalfunctions = adddep;
 388                 symbolsonly       = adddep;
 389                 singlefunctions   = adddep2;
 390                 parse_file(infile);
 391                 printf("\n");
 392         }
 393         else
 394         {
 395                 fprintf(stderr, "Unknown option: %s\n", argv[1]);
 396                 exit(1);
 397         }
 398         fclose(infile);
 399         fflush(stdout);
 400         return exitstatus;
 401 }