tools/perf/util/config.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  * Copyright (C) Johannes Schindelin, 2005
   6  *
   7  */
   8 #include "util.h"
   9 #include "cache.h"
  10 #include "exec_cmd.h"
  11
  12 #define MAXNAME (256)
  13
  14 #define DEBUG_CACHE_DIR ".debug"
  15
  16
  17 char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */
  18
  19 static FILE *config_file;
  20 static const char *config_file_name;
  21 static int config_linenr;
  22 static int config_file_eof;
  23
  24 static const char *config_exclusive_filename;
  25
  26 static int get_next_char(void)
  27 {
  28         int c;
  29         FILE *f;
  30
  31         c = '\n';
  32         if ((f = config_file) != NULL) {
  33                 c = fgetc(f);
  34                 if (c == '\r') {
  35                         /* DOS like systems */
  36                         c = fgetc(f);
  37                         if (c != '\n') {
  38                                 ungetc(c, f);
  39                                 c = '\r';
  40                         }
  41                 }
  42                 if (c == '\n')
  43                         config_linenr++;
  44                 if (c == EOF) {
  45                         config_file_eof = 1;
  46                         c = '\n';
  47                 }
  48         }
  49         return c;
  50 }
  51
  52 static char *parse_value(void)
  53 {
  54         static char value[1024];
  55         int quote = 0, comment = 0, space = 0;
  56         size_t len = 0;
  57
  58         for (;;) {
  59                 int c = get_next_char();
  60
  61                 if (len >= sizeof(value) - 1)
  62                         return NULL;
  63                 if (c == '\n') {
  64                         if (quote)
  65                                 return NULL;
  66                         value[len] = 0;
  67                         return value;
  68                 }
  69                 if (comment)
  70                         continue;
  71                 if (isspace(c) && !quote) {
  72                         space = 1;
  73                         continue;
  74                 }
  75                 if (!quote) {
  76                         if (c == ';' || c == '#') {
  77                                 comment = 1;
  78                                 continue;
  79                         }
  80                 }
  81                 if (space) {
  82                         if (len)
  83                                 value[len++] = ' ';
  84                         space = 0;
  85                 }
  86                 if (c == '\\') {
  87                         c = get_next_char();
  88                         switch (c) {
  89                         case '\n':
  90                                 continue;
  91                         case 't':
  92                                 c = '\t';
  93                                 break;
  94                         case 'b':
  95                                 c = '\b';
  96                                 break;
  97                         case 'n':
  98                                 c = '\n';
  99                                 break;
 100                         /* Some characters escape as themselves */
 101                         case '\\': case '"':
 102                                 break;
 103                         /* Reject unknown escape sequences */
 104                         default:
 105                                 return NULL;
 106                         }
 107                         value[len++] = c;
 108                         continue;
 109                 }
 110                 if (c == '"') {
 111                         quote = 1-quote;
 112                         continue;
 113                 }
 114                 value[len++] = c;
 115         }
 116 }
 117
 118 static inline int iskeychar(int c)
 119 {
 120         return isalnum(c) || c == '-';
 121 }
 122
 123 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 124 {
 125         int c;
 126         char *value;
 127
 128         /* Get the full name */
 129         for (;;) {
 130                 c = get_next_char();
 131                 if (config_file_eof)
 132                         break;
 133                 if (!iskeychar(c))
 134                         break;
 135                 name[len++] = c;
 136                 if (len >= MAXNAME)
 137                         return -1;
 138         }
 139         name[len] = 0;
 140         while (c == ' ' || c == '\t')
 141                 c = get_next_char();
 142
 143         value = NULL;
 144         if (c != '\n') {
 145                 if (c != '=')
 146                         return -1;
 147                 value = parse_value();
 148                 if (!value)
 149                         return -1;
 150         }
 151         return fn(name, value, data);
 152 }
 153
 154 static int get_extended_base_var(char *name, int baselen, int c)
 155 {
 156         do {
 157                 if (c == '\n')
 158                         return -1;
 159                 c = get_next_char();
 160         } while (isspace(c));
 161
 162         /* We require the format to be '[base "extension"]' */
 163         if (c != '"')
 164                 return -1;
 165         name[baselen++] = '.';
 166
 167         for (;;) {
 168                 int ch = get_next_char();
 169
 170                 if (ch == '\n')
 171                         return -1;
 172                 if (ch == '"')
 173                         break;
 174                 if (ch == '\\') {
 175                         ch = get_next_char();
 176                         if (ch == '\n')
 177                                 return -1;
 178                 }
 179                 name[baselen++] = ch;
 180                 if (baselen > MAXNAME / 2)
 181                         return -1;
 182         }
 183
 184         /* Final ']' */
 185         if (get_next_char() != ']')
 186                 return -1;
 187         return baselen;
 188 }
 189
 190 static int get_base_var(char *name)
 191 {
 192         int baselen = 0;
 193
 194         for (;;) {
 195                 int c = get_next_char();
 196                 if (config_file_eof)
 197                         return -1;
 198                 if (c == ']')
 199                         return baselen;
 200                 if (isspace(c))
 201                         return get_extended_base_var(name, baselen, c);
 202                 if (!iskeychar(c) && c != '.')
 203                         return -1;
 204                 if (baselen > MAXNAME / 2)
 205                         return -1;
 206                 name[baselen++] = tolower(c);
 207         }
 208 }
 209
 210 static int perf_parse_file(config_fn_t fn, void *data)
 211 {
 212         int comment = 0;
 213         int baselen = 0;
 214         static char var[MAXNAME];
 215
 216         /* U+FEFF Byte Order Mark in UTF8 */
 217         static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 218         const unsigned char *bomptr = utf8_bom;
 219
 220         for (;;) {
 221                 int c = get_next_char();
 222                 if (bomptr && *bomptr) {
 223                         /* We are at the file beginning; skip UTF8-encoded BOM
 224                          * if present. Sane editors won't put this in on their
 225                          * own, but e.g. Windows Notepad will do it happily. */
 226                         if ((unsigned char) c == *bomptr) {
 227                                 bomptr++;
 228                                 continue;
 229                         } else {
 230                                 /* Do not tolerate partial BOM. */
 231                                 if (bomptr != utf8_bom)
 232                                         break;
 233                                 /* No BOM at file beginning. Cool. */
 234                                 bomptr = NULL;
 235                         }
 236                 }
 237                 if (c == '\n') {
 238                         if (config_file_eof)
 239                                 return 0;
 240                         comment = 0;
 241                         continue;
 242                 }
 243                 if (comment || isspace(c))
 244                         continue;
 245                 if (c == '#' || c == ';') {
 246                         comment = 1;
 247                         continue;
 248                 }
 249                 if (c == '[') {
 250                         baselen = get_base_var(var);
 251                         if (baselen <= 0)
 252                                 break;
 253                         var[baselen++] = '.';
 254                         var[baselen] = 0;
 255                         continue;
 256                 }
 257                 if (!isalpha(c))
 258                         break;
 259                 var[baselen] = tolower(c);
 260                 if (get_value(fn, data, var, baselen+1) < 0)
 261                         break;
 262         }
 263         die("bad config file line %d in %s", config_linenr, config_file_name);
 264 }
 265
 266 static int parse_unit_factor(const char *end, unsigned long *val)
 267 {
 268         if (!*end)
 269                 return 1;
 270         else if (!strcasecmp(end, "k")) {
 271                 *val *= 1024;
 272                 return 1;
 273         }
 274         else if (!strcasecmp(end, "m")) {
 275                 *val *= 1024 * 1024;
 276                 return 1;
 277         }
 278         else if (!strcasecmp(end, "g")) {
 279                 *val *= 1024 * 1024 * 1024;
 280                 return 1;
 281         }
 282         return 0;
 283 }
 284
 285 static int perf_parse_long(const char *value, long *ret)
 286 {
 287         if (value && *value) {
 288                 char *end;
 289                 long val = strtol(value, &end, 0);
 290                 unsigned long factor = 1;
 291                 if (!parse_unit_factor(end, &factor))
 292                         return 0;
 293                 *ret = val * factor;
 294                 return 1;
 295         }
 296         return 0;
 297 }
 298
 299 static void die_bad_config(const char *name)
 300 {
 301         if (config_file_name)
 302                 die("bad config value for '%s' in %s", name, config_file_name);
 303         die("bad config value for '%s'", name);
 304 }
 305
 306 int perf_config_int(const char *name, const char *value)
 307 {
 308         long ret = 0;
 309         if (!perf_parse_long(value, &ret))
 310                 die_bad_config(name);
 311         return ret;
 312 }
 313
 314 static int perf_config_bool_or_int(const char *name, const char *value, int *is_bool)
 315 {
 316         *is_bool = 1;
 317         if (!value)
 318                 return 1;
 319         if (!*value)
 320                 return 0;
 321         if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 322                 return 1;
 323         if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 324                 return 0;
 325         *is_bool = 0;
 326         return perf_config_int(name, value);
 327 }
 328
 329 int perf_config_bool(const char *name, const char *value)
 330 {
 331         int discard;
 332         return !!perf_config_bool_or_int(name, value, &discard);
 333 }
 334
 335 const char *perf_config_dirname(const char *name, const char *value)
 336 {
 337         if (!name)
 338                 return NULL;
 339         return value;
 340 }
 341
 342 static int perf_default_core_config(const char *var __used, const char *value __used)
 343 {
 344         /* Add other config variables here and to Documentation/config.txt. */
 345         return 0;
 346 }
 347
 348 int perf_default_config(const char *var, const char *value, void *dummy __used)
 349 {
 350         if (!prefixcmp(var, "core."))
 351                 return perf_default_core_config(var, value);
 352
 353         /* Add other config variables here and to Documentation/config.txt. */
 354         return 0;
 355 }
 356
 357 static int perf_config_from_file(config_fn_t fn, const char *filename, void *data)
 358 {
 359         int ret;
 360         FILE *f = fopen(filename, "r");
 361
 362         ret = -1;
 363         if (f) {
 364                 config_file = f;
 365                 config_file_name = filename;
 366                 config_linenr = 1;
 367                 config_file_eof = 0;
 368                 ret = perf_parse_file(fn, data);
 369                 fclose(f);
 370                 config_file_name = NULL;
 371         }
 372         return ret;
 373 }
 374
 375 static const char *perf_etc_perfconfig(void)
 376 {
 377         static const char *system_wide;
 378         if (!system_wide)
 379                 system_wide = system_path(ETC_PERFCONFIG);
 380         return system_wide;
 381 }
 382
 383 static int perf_env_bool(const char *k, int def)
 384 {
 385         const char *v = getenv(k);
 386         return v ? perf_config_bool(k, v) : def;
 387 }
 388
 389 static int perf_config_system(void)
 390 {
 391         return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0);
 392 }
 393
 394 static int perf_config_global(void)
 395 {
 396         return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0);
 397 }
 398
 399 int perf_config(config_fn_t fn, void *data)
 400 {
 401         int ret = 0, found = 0;
 402         char *repo_config = NULL;
 403         const char *home = NULL;
 404
 405         /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
 406         if (config_exclusive_filename)
 407                 return perf_config_from_file(fn, config_exclusive_filename, data);
 408         if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
 409                 ret += perf_config_from_file(fn, perf_etc_perfconfig(),
 410                                             data);
 411                 found += 1;
 412         }
 413
 414         home = getenv("HOME");
 415         if (perf_config_global() && home) {
 416                 char *user_config = strdup(mkpath("%s/.perfconfig", home));
 417                 if (!access(user_config, R_OK)) {
 418                         ret += perf_config_from_file(fn, user_config, data);
 419                         found += 1;
 420                 }
 421                 free(user_config);
 422         }
 423
 424         repo_config = perf_pathdup("config");
 425         if (!access(repo_config, R_OK)) {
 426                 ret += perf_config_from_file(fn, repo_config, data);
 427                 found += 1;
 428         }
 429         free(repo_config);
 430         if (found == 0)
 431                 return -1;
 432         return ret;
 433 }
 434
 435 /*
 436  * Call this to report error for your variable that should not
 437  * get a boolean value (i.e. "[my] var" means "true").
 438  */
 439 int config_error_nonbool(const char *var)
 440 {
 441         return error("Missing value for '%s'", var);
 442 }
 443
 444 struct buildid_dir_config {
 445         char *dir;
 446 };
 447
 448 static int buildid_dir_command_config(const char *var, const char *value,
 449                                       void *data)
 450 {
 451         struct buildid_dir_config *c = data;
 452         const char *v;
 453
 454         /* same dir for all commands */
 455         if (!prefixcmp(var, "buildid.") && !strcmp(var + 8, "dir")) {
 456                 v = perf_config_dirname(var, value);
 457                 if (!v)
 458                         return -1;
 459                 strncpy(c->dir, v, MAXPATHLEN-1);
 460                 c->dir[MAXPATHLEN-1] = '\0';
 461         }
 462         return 0;
 463 }
 464
 465 static void check_buildid_dir_config(void)
 466 {
 467         struct buildid_dir_config c;
 468         c.dir = buildid_dir;
 469         perf_config(buildid_dir_command_config, &c);
 470 }
 471
 472 void set_buildid_dir(void)
 473 {
 474         buildid_dir[0] = '\0';
 475
 476         /* try config file */
 477         check_buildid_dir_config();
 478
 479         /* default to $HOME/.debug */
 480         if (buildid_dir[0] == '\0') {
 481                 char *v = getenv("HOME");
 482                 if (v) {
 483                         snprintf(buildid_dir, MAXPATHLEN-1, "%s/%s",
 484                                  v, DEBUG_CACHE_DIR);
 485                 } else {
 486                         strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1);
 487                 }
 488                 buildid_dir[MAXPATHLEN-1] = '\0';
 489         }
 490         /* for communicating with external commands */
 491         setenv("PERF_BUILDID_DIR", buildid_dir, 1);
 492 }