1 /*
2 * config.c
3 *
4 * Helper functions for parsing config items.
5 * Originally copied from GIT source.
6 *
7 * Copyright (C) Linus Torvalds, 2005
8 * Copyright (C) Johannes Schindelin, 2005
9 *
10 */
11 #include "util.h"
12 #include "cache.h"
13 #include "exec_cmd.h"
14 #include "util/hist.h" /* perf_hist_config */
15
16 #define MAXNAME (256)
17
18 #define DEBUG_CACHE_DIR ".debug"
19
20
21 char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */
22
23 static FILE *config_file;
24 static const char *config_file_name;
25 static int config_linenr;
26 static int config_file_eof;
27
28 static const char *config_exclusive_filename;
29
get_next_char(void)30 static int get_next_char(void)
31 {
32 int c;
33 FILE *f;
34
35 c = '\n';
36 if ((f = config_file) != NULL) {
37 c = fgetc(f);
38 if (c == '\r') {
39 /* DOS like systems */
40 c = fgetc(f);
41 if (c != '\n') {
42 ungetc(c, f);
43 c = '\r';
44 }
45 }
46 if (c == '\n')
47 config_linenr++;
48 if (c == EOF) {
49 config_file_eof = 1;
50 c = '\n';
51 }
52 }
53 return c;
54 }
55
parse_value(void)56 static char *parse_value(void)
57 {
58 static char value[1024];
59 int quote = 0, comment = 0, space = 0;
60 size_t len = 0;
61
62 for (;;) {
63 int c = get_next_char();
64
65 if (len >= sizeof(value) - 1)
66 return NULL;
67 if (c == '\n') {
68 if (quote)
69 return NULL;
70 value[len] = 0;
71 return value;
72 }
73 if (comment)
74 continue;
75 if (isspace(c) && !quote) {
76 space = 1;
77 continue;
78 }
79 if (!quote) {
80 if (c == ';' || c == '#') {
81 comment = 1;
82 continue;
83 }
84 }
85 if (space) {
86 if (len)
87 value[len++] = ' ';
88 space = 0;
89 }
90 if (c == '\\') {
91 c = get_next_char();
92 switch (c) {
93 case '\n':
94 continue;
95 case 't':
96 c = '\t';
97 break;
98 case 'b':
99 c = '\b';
100 break;
101 case 'n':
102 c = '\n';
103 break;
104 /* Some characters escape as themselves */
105 case '\\': case '"':
106 break;
107 /* Reject unknown escape sequences */
108 default:
109 return NULL;
110 }
111 value[len++] = c;
112 continue;
113 }
114 if (c == '"') {
115 quote = 1-quote;
116 continue;
117 }
118 value[len++] = c;
119 }
120 }
121
iskeychar(int c)122 static inline int iskeychar(int c)
123 {
124 return isalnum(c) || c == '-' || c == '_';
125 }
126
get_value(config_fn_t fn,void * data,char * name,unsigned int len)127 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
128 {
129 int c;
130 char *value;
131
132 /* Get the full name */
133 for (;;) {
134 c = get_next_char();
135 if (config_file_eof)
136 break;
137 if (!iskeychar(c))
138 break;
139 name[len++] = c;
140 if (len >= MAXNAME)
141 return -1;
142 }
143 name[len] = 0;
144 while (c == ' ' || c == '\t')
145 c = get_next_char();
146
147 value = NULL;
148 if (c != '\n') {
149 if (c != '=')
150 return -1;
151 value = parse_value();
152 if (!value)
153 return -1;
154 }
155 return fn(name, value, data);
156 }
157
get_extended_base_var(char * name,int baselen,int c)158 static int get_extended_base_var(char *name, int baselen, int c)
159 {
160 do {
161 if (c == '\n')
162 return -1;
163 c = get_next_char();
164 } while (isspace(c));
165
166 /* We require the format to be '[base "extension"]' */
167 if (c != '"')
168 return -1;
169 name[baselen++] = '.';
170
171 for (;;) {
172 int ch = get_next_char();
173
174 if (ch == '\n')
175 return -1;
176 if (ch == '"')
177 break;
178 if (ch == '\\') {
179 ch = get_next_char();
180 if (ch == '\n')
181 return -1;
182 }
183 name[baselen++] = ch;
184 if (baselen > MAXNAME / 2)
185 return -1;
186 }
187
188 /* Final ']' */
189 if (get_next_char() != ']')
190 return -1;
191 return baselen;
192 }
193
get_base_var(char * name)194 static int get_base_var(char *name)
195 {
196 int baselen = 0;
197
198 for (;;) {
199 int c = get_next_char();
200 if (config_file_eof)
201 return -1;
202 if (c == ']')
203 return baselen;
204 if (isspace(c))
205 return get_extended_base_var(name, baselen, c);
206 if (!iskeychar(c) && c != '.')
207 return -1;
208 if (baselen > MAXNAME / 2)
209 return -1;
210 name[baselen++] = tolower(c);
211 }
212 }
213
perf_parse_file(config_fn_t fn,void * data)214 static int perf_parse_file(config_fn_t fn, void *data)
215 {
216 int comment = 0;
217 int baselen = 0;
218 static char var[MAXNAME];
219
220 /* U+FEFF Byte Order Mark in UTF8 */
221 static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
222 const unsigned char *bomptr = utf8_bom;
223
224 for (;;) {
225 int line, c = get_next_char();
226
227 if (bomptr && *bomptr) {
228 /* We are at the file beginning; skip UTF8-encoded BOM
229 * if present. Sane editors won't put this in on their
230 * own, but e.g. Windows Notepad will do it happily. */
231 if ((unsigned char) c == *bomptr) {
232 bomptr++;
233 continue;
234 } else {
235 /* Do not tolerate partial BOM. */
236 if (bomptr != utf8_bom)
237 break;
238 /* No BOM at file beginning. Cool. */
239 bomptr = NULL;
240 }
241 }
242 if (c == '\n') {
243 if (config_file_eof)
244 return 0;
245 comment = 0;
246 continue;
247 }
248 if (comment || isspace(c))
249 continue;
250 if (c == '#' || c == ';') {
251 comment = 1;
252 continue;
253 }
254 if (c == '[') {
255 baselen = get_base_var(var);
256 if (baselen <= 0)
257 break;
258 var[baselen++] = '.';
259 var[baselen] = 0;
260 continue;
261 }
262 if (!isalpha(c))
263 break;
264 var[baselen] = tolower(c);
265
266 /*
267 * The get_value function might or might not reach the '\n',
268 * so saving the current line number for error reporting.
269 */
270 line = config_linenr;
271 if (get_value(fn, data, var, baselen+1) < 0) {
272 config_linenr = line;
273 break;
274 }
275 }
276 die("bad config file line %d in %s", config_linenr, config_file_name);
277 }
278
parse_unit_factor(const char * end,unsigned long * val)279 static int parse_unit_factor(const char *end, unsigned long *val)
280 {
281 if (!*end)
282 return 1;
283 else if (!strcasecmp(end, "k")) {
284 *val *= 1024;
285 return 1;
286 }
287 else if (!strcasecmp(end, "m")) {
288 *val *= 1024 * 1024;
289 return 1;
290 }
291 else if (!strcasecmp(end, "g")) {
292 *val *= 1024 * 1024 * 1024;
293 return 1;
294 }
295 return 0;
296 }
297
perf_parse_llong(const char * value,long long * ret)298 static int perf_parse_llong(const char *value, long long *ret)
299 {
300 if (value && *value) {
301 char *end;
302 long long val = strtoll(value, &end, 0);
303 unsigned long factor = 1;
304
305 if (!parse_unit_factor(end, &factor))
306 return 0;
307 *ret = val * factor;
308 return 1;
309 }
310 return 0;
311 }
312
perf_parse_long(const char * value,long * ret)313 static int perf_parse_long(const char *value, long *ret)
314 {
315 if (value && *value) {
316 char *end;
317 long val = strtol(value, &end, 0);
318 unsigned long factor = 1;
319 if (!parse_unit_factor(end, &factor))
320 return 0;
321 *ret = val * factor;
322 return 1;
323 }
324 return 0;
325 }
326
die_bad_config(const char * name)327 static void die_bad_config(const char *name)
328 {
329 if (config_file_name)
330 die("bad config value for '%s' in %s", name, config_file_name);
331 die("bad config value for '%s'", name);
332 }
333
perf_config_u64(const char * name,const char * value)334 u64 perf_config_u64(const char *name, const char *value)
335 {
336 long long ret = 0;
337
338 if (!perf_parse_llong(value, &ret))
339 die_bad_config(name);
340 return (u64) ret;
341 }
342
perf_config_int(const char * name,const char * value)343 int perf_config_int(const char *name, const char *value)
344 {
345 long ret = 0;
346 if (!perf_parse_long(value, &ret))
347 die_bad_config(name);
348 return ret;
349 }
350
perf_config_bool_or_int(const char * name,const char * value,int * is_bool)351 static int perf_config_bool_or_int(const char *name, const char *value, int *is_bool)
352 {
353 *is_bool = 1;
354 if (!value)
355 return 1;
356 if (!*value)
357 return 0;
358 if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
359 return 1;
360 if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
361 return 0;
362 *is_bool = 0;
363 return perf_config_int(name, value);
364 }
365
perf_config_bool(const char * name,const char * value)366 int perf_config_bool(const char *name, const char *value)
367 {
368 int discard;
369 return !!perf_config_bool_or_int(name, value, &discard);
370 }
371
perf_config_dirname(const char * name,const char * value)372 const char *perf_config_dirname(const char *name, const char *value)
373 {
374 if (!name)
375 return NULL;
376 return value;
377 }
378
perf_default_core_config(const char * var __maybe_unused,const char * value __maybe_unused)379 static int perf_default_core_config(const char *var __maybe_unused,
380 const char *value __maybe_unused)
381 {
382 /* Add other config variables here. */
383 return 0;
384 }
385
perf_ui_config(const char * var,const char * value)386 static int perf_ui_config(const char *var, const char *value)
387 {
388 /* Add other config variables here. */
389 if (!strcmp(var, "ui.show-headers")) {
390 symbol_conf.show_hist_headers = perf_config_bool(var, value);
391 return 0;
392 }
393 return 0;
394 }
395
perf_default_config(const char * var,const char * value,void * dummy __maybe_unused)396 int perf_default_config(const char *var, const char *value,
397 void *dummy __maybe_unused)
398 {
399 if (!prefixcmp(var, "core."))
400 return perf_default_core_config(var, value);
401
402 if (!prefixcmp(var, "hist."))
403 return perf_hist_config(var, value);
404
405 if (!prefixcmp(var, "ui."))
406 return perf_ui_config(var, value);
407
408 if (!prefixcmp(var, "call-graph."))
409 return perf_callchain_config(var, value);
410
411 /* Add other config variables here. */
412 return 0;
413 }
414
perf_config_from_file(config_fn_t fn,const char * filename,void * data)415 static int perf_config_from_file(config_fn_t fn, const char *filename, void *data)
416 {
417 int ret;
418 FILE *f = fopen(filename, "r");
419
420 ret = -1;
421 if (f) {
422 config_file = f;
423 config_file_name = filename;
424 config_linenr = 1;
425 config_file_eof = 0;
426 ret = perf_parse_file(fn, data);
427 fclose(f);
428 config_file_name = NULL;
429 }
430 return ret;
431 }
432
perf_etc_perfconfig(void)433 static const char *perf_etc_perfconfig(void)
434 {
435 static const char *system_wide;
436 if (!system_wide)
437 system_wide = system_path(ETC_PERFCONFIG);
438 return system_wide;
439 }
440
perf_env_bool(const char * k,int def)441 static int perf_env_bool(const char *k, int def)
442 {
443 const char *v = getenv(k);
444 return v ? perf_config_bool(k, v) : def;
445 }
446
perf_config_system(void)447 static int perf_config_system(void)
448 {
449 return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0);
450 }
451
perf_config_global(void)452 static int perf_config_global(void)
453 {
454 return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0);
455 }
456
perf_config(config_fn_t fn,void * data)457 int perf_config(config_fn_t fn, void *data)
458 {
459 int ret = 0, found = 0;
460 const char *home = NULL;
461
462 /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
463 if (config_exclusive_filename)
464 return perf_config_from_file(fn, config_exclusive_filename, data);
465 if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
466 ret += perf_config_from_file(fn, perf_etc_perfconfig(),
467 data);
468 found += 1;
469 }
470
471 home = getenv("HOME");
472 if (perf_config_global() && home) {
473 char *user_config = strdup(mkpath("%s/.perfconfig", home));
474 struct stat st;
475
476 if (user_config == NULL) {
477 warning("Not enough memory to process %s/.perfconfig, "
478 "ignoring it.", home);
479 goto out;
480 }
481
482 if (stat(user_config, &st) < 0)
483 goto out_free;
484
485 if (st.st_uid && (st.st_uid != geteuid())) {
486 warning("File %s not owned by current user or root, "
487 "ignoring it.", user_config);
488 goto out_free;
489 }
490
491 if (!st.st_size)
492 goto out_free;
493
494 ret += perf_config_from_file(fn, user_config, data);
495 found += 1;
496 out_free:
497 free(user_config);
498 }
499 out:
500 if (found == 0)
501 return -1;
502 return ret;
503 }
504
505 /*
506 * Call this to report error for your variable that should not
507 * get a boolean value (i.e. "[my] var" means "true").
508 */
config_error_nonbool(const char * var)509 int config_error_nonbool(const char *var)
510 {
511 return error("Missing value for '%s'", var);
512 }
513
514 struct buildid_dir_config {
515 char *dir;
516 };
517
buildid_dir_command_config(const char * var,const char * value,void * data)518 static int buildid_dir_command_config(const char *var, const char *value,
519 void *data)
520 {
521 struct buildid_dir_config *c = data;
522 const char *v;
523
524 /* same dir for all commands */
525 if (!prefixcmp(var, "buildid.") && !strcmp(var + 8, "dir")) {
526 v = perf_config_dirname(var, value);
527 if (!v)
528 return -1;
529 strncpy(c->dir, v, MAXPATHLEN-1);
530 c->dir[MAXPATHLEN-1] = '\0';
531 }
532 return 0;
533 }
534
check_buildid_dir_config(void)535 static void check_buildid_dir_config(void)
536 {
537 struct buildid_dir_config c;
538 c.dir = buildid_dir;
539 perf_config(buildid_dir_command_config, &c);
540 }
541
set_buildid_dir(void)542 void set_buildid_dir(void)
543 {
544 buildid_dir[0] = '\0';
545
546 /* try config file */
547 check_buildid_dir_config();
548
549 /* default to $HOME/.debug */
550 if (buildid_dir[0] == '\0') {
551 char *v = getenv("HOME");
552 if (v) {
553 snprintf(buildid_dir, MAXPATHLEN-1, "%s/%s",
554 v, DEBUG_CACHE_DIR);
555 } else {
556 strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1);
557 }
558 buildid_dir[MAXPATHLEN-1] = '\0';
559 }
560 /* for communicating with external commands */
561 setenv("PERF_BUILDID_DIR", buildid_dir, 1);
562 }
563