1 #include "jemalloc/internal/jemalloc_preamble.h"
2 #include "jemalloc/internal/jemalloc_internal_includes.h"
3
4 #include "jemalloc/internal/log.h"
5
6 char log_var_names[JEMALLOC_LOG_VAR_BUFSIZE];
7 atomic_b_t log_init_done = ATOMIC_INIT(false);
8
9 /*
10 * Returns true if we were able to pick out a segment. Fills in r_segment_end
11 * with a pointer to the first character after the end of the string.
12 */
13 static const char *
log_var_extract_segment(const char * segment_begin)14 log_var_extract_segment(const char* segment_begin) {
15 const char *end;
16 for (end = segment_begin; *end != '\0' && *end != '|'; end++) {
17 }
18 return end;
19 }
20
21 static bool
log_var_matches_segment(const char * segment_begin,const char * segment_end,const char * log_var_begin,const char * log_var_end)22 log_var_matches_segment(const char *segment_begin, const char *segment_end,
23 const char *log_var_begin, const char *log_var_end) {
24 assert(segment_begin <= segment_end);
25 assert(log_var_begin < log_var_end);
26
27 ptrdiff_t segment_len = segment_end - segment_begin;
28 ptrdiff_t log_var_len = log_var_end - log_var_begin;
29 /* The special '.' segment matches everything. */
30 if (segment_len == 1 && *segment_begin == '.') {
31 return true;
32 }
33 if (segment_len == log_var_len) {
34 return strncmp(segment_begin, log_var_begin, segment_len) == 0;
35 } else if (segment_len < log_var_len) {
36 return strncmp(segment_begin, log_var_begin, segment_len) == 0
37 && log_var_begin[segment_len] == '.';
38 } else {
39 return false;
40 }
41 }
42
43 unsigned
log_var_update_state(log_var_t * log_var)44 log_var_update_state(log_var_t *log_var) {
45 const char *log_var_begin = log_var->name;
46 const char *log_var_end = log_var->name + strlen(log_var->name);
47
48 /* Pointer to one before the beginning of the current segment. */
49 const char *segment_begin = log_var_names;
50
51 /*
52 * If log_init done is false, we haven't parsed the malloc conf yet. To
53 * avoid log-spew, we default to not displaying anything.
54 */
55 if (!atomic_load_b(&log_init_done, ATOMIC_ACQUIRE)) {
56 return LOG_INITIALIZED_NOT_ENABLED;
57 }
58
59 while (true) {
60 const char *segment_end = log_var_extract_segment(
61 segment_begin);
62 assert(segment_end < log_var_names + JEMALLOC_LOG_VAR_BUFSIZE);
63 if (log_var_matches_segment(segment_begin, segment_end,
64 log_var_begin, log_var_end)) {
65 atomic_store_u(&log_var->state, LOG_ENABLED,
66 ATOMIC_RELAXED);
67 return LOG_ENABLED;
68 }
69 if (*segment_end == '\0') {
70 /* Hit the end of the segment string with no match. */
71 atomic_store_u(&log_var->state,
72 LOG_INITIALIZED_NOT_ENABLED, ATOMIC_RELAXED);
73 return LOG_INITIALIZED_NOT_ENABLED;
74 }
75 /* Otherwise, skip the delimiter and continue. */
76 segment_begin = segment_end + 1;
77 }
78 }
79