diff options
Diffstat (limited to 'ring.c')
| -rw-r--r-- | ring.c | 36 |
1 files changed, 22 insertions, 14 deletions
diff --git a/ring.c b/ring.c index 474a6e4..0fec6d0 100644 --- a/ring.c +++ b/ring.c @@ -23,18 +23,25 @@ #include "bounce.h" -enum { RingLen = 4096 }; -static_assert(!(RingLen & (RingLen - 1)), "power of two RingLen"); - static struct { - char *lines[RingLen]; - time_t times[RingLen]; + size_t len; + char **lines; + time_t *times; } ring; +void ringAlloc(size_t len) { + if (len & (len - 1)) errx(EX_CONFIG, "ring length must be power of two"); + ring.lines = calloc(len, sizeof(*ring.lines)); + if (!ring.lines) err(EX_OSERR, "calloc"); + ring.times = calloc(len, sizeof(*ring.times)); + if (!ring.times) err(EX_OSERR, "calloc"); + ring.len = len; +} + size_t producer; void ringProduce(const char *line) { - size_t i = producer++ % RingLen; + size_t i = producer++ & (ring.len - 1); if (ring.lines[i]) free(ring.lines[i]); ring.times[i] = time(NULL); ring.lines[i] = strdup(line); @@ -79,17 +86,18 @@ size_t ringDiff(size_t consumer) { const char *ringPeek(time_t *time, size_t consumer) { if (!ringDiff(consumer)) return NULL; - if (ringDiff(consumer) > RingLen) { - consumers.ptr[consumer].pos = producer - RingLen; + if (ringDiff(consumer) > ring.len) { + consumers.ptr[consumer].pos = producer - ring.len; } - size_t i = consumers.ptr[consumer].pos % RingLen; + size_t i = consumers.ptr[consumer].pos & (ring.len - 1); if (time) *time = ring.times[i]; + assert(ring.lines[i]); return ring.lines[i]; } const char *ringConsume(time_t *time, size_t consumer) { const char *line = ringPeek(time, consumer); - consumers.ptr[consumer].pos++; + if (line) consumers.ptr[consumer].pos++; return line; } @@ -124,10 +132,10 @@ int ringSave(FILE *file) { if (writeString(file, consumers.ptr[i].name)) return -1; if (writeSize(file, consumers.ptr[i].pos)) return -1; } - for (size_t i = 0; i < RingLen; ++i) { + for (size_t i = 0; i < ring.len; ++i) { if (writeTime(file, ring.times[i])) return -1; } - for (size_t i = 0; i < RingLen; ++i) { + for (size_t i = 0; i < ring.len; ++i) { if (!ring.lines[i]) break; if (writeString(file, ring.lines[i])) return -1; } @@ -169,10 +177,10 @@ void ringLoad(FILE *file) { readSize(file, &consumers.ptr[consumer].pos); } - for (size_t i = 0; i < RingLen; ++i) { + for (size_t i = 0; i < ring.len; ++i) { readTime(file, &ring.times[i]); } - for (size_t i = 0; i < RingLen; ++i) { + for (size_t i = 0; i < ring.len; ++i) { readString(file, &buf, &cap); if (feof(file)) break; ring.lines[i] = strdup(buf); |