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