Mercurial > hg > nginx
view src/http/ngx_http_huff_encode.c @ 7985:ec2e6893caaa
Simplified sendfile(SF_NODISKIO) usage.
Starting with FreeBSD 11, there is no need to use AIO operations to preload
data into cache for sendfile(SF_NODISKIO) to work. Instead, sendfile()
handles non-blocking loading data from disk by itself. It still can, however,
return EBUSY if a page is already being loaded (for example, by a different
process). If this happens, we now post an event for the next event loop
iteration, so sendfile() is retried "after a short period", as manpage
recommends.
The limit of the number of EBUSY tolerated without any progress is preserved,
but now it does not result in an alert, since on an idle system event loop
iteration might be very short and EBUSY can happen many times in a row.
Instead, SF_NODISKIO is simply disabled for one call once the limit is
reached.
With this change, sendfile(SF_NODISKIO) is now used automatically as long as
sendfile() is enabled, and no longer requires "aio on;".
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 27 Dec 2021 19:48:33 +0300 |
parents | 336084ff943b |
children |
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/* * Copyright (C) Nginx, Inc. * Copyright (C) Valentin V. Bartenev * Copyright (C) 2015 Vlad Krasnov */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { uint32_t code; uint32_t len; } ngx_http_huff_encode_code_t; static ngx_http_huff_encode_code_t ngx_http_huff_encode_table[256] = { {0x00001ff8, 13}, {0x007fffd8, 23}, {0x0fffffe2, 28}, {0x0fffffe3, 28}, {0x0fffffe4, 28}, {0x0fffffe5, 28}, {0x0fffffe6, 28}, {0x0fffffe7, 28}, {0x0fffffe8, 28}, {0x00ffffea, 24}, {0x3ffffffc, 30}, {0x0fffffe9, 28}, {0x0fffffea, 28}, {0x3ffffffd, 30}, {0x0fffffeb, 28}, {0x0fffffec, 28}, {0x0fffffed, 28}, {0x0fffffee, 28}, {0x0fffffef, 28}, {0x0ffffff0, 28}, {0x0ffffff1, 28}, {0x0ffffff2, 28}, {0x3ffffffe, 30}, {0x0ffffff3, 28}, {0x0ffffff4, 28}, {0x0ffffff5, 28}, {0x0ffffff6, 28}, {0x0ffffff7, 28}, {0x0ffffff8, 28}, {0x0ffffff9, 28}, {0x0ffffffa, 28}, {0x0ffffffb, 28}, {0x00000014, 6}, {0x000003f8, 10}, {0x000003f9, 10}, {0x00000ffa, 12}, {0x00001ff9, 13}, {0x00000015, 6}, {0x000000f8, 8}, {0x000007fa, 11}, {0x000003fa, 10}, {0x000003fb, 10}, {0x000000f9, 8}, {0x000007fb, 11}, {0x000000fa, 8}, {0x00000016, 6}, {0x00000017, 6}, {0x00000018, 6}, {0x00000000, 5}, {0x00000001, 5}, {0x00000002, 5}, {0x00000019, 6}, {0x0000001a, 6}, {0x0000001b, 6}, {0x0000001c, 6}, {0x0000001d, 6}, {0x0000001e, 6}, {0x0000001f, 6}, {0x0000005c, 7}, {0x000000fb, 8}, {0x00007ffc, 15}, {0x00000020, 6}, {0x00000ffb, 12}, {0x000003fc, 10}, {0x00001ffa, 13}, {0x00000021, 6}, {0x0000005d, 7}, {0x0000005e, 7}, {0x0000005f, 7}, {0x00000060, 7}, {0x00000061, 7}, {0x00000062, 7}, {0x00000063, 7}, {0x00000064, 7}, {0x00000065, 7}, {0x00000066, 7}, {0x00000067, 7}, {0x00000068, 7}, {0x00000069, 7}, {0x0000006a, 7}, {0x0000006b, 7}, {0x0000006c, 7}, {0x0000006d, 7}, {0x0000006e, 7}, {0x0000006f, 7}, {0x00000070, 7}, {0x00000071, 7}, {0x00000072, 7}, {0x000000fc, 8}, {0x00000073, 7}, {0x000000fd, 8}, {0x00001ffb, 13}, {0x0007fff0, 19}, {0x00001ffc, 13}, {0x00003ffc, 14}, {0x00000022, 6}, {0x00007ffd, 15}, {0x00000003, 5}, {0x00000023, 6}, {0x00000004, 5}, {0x00000024, 6}, {0x00000005, 5}, {0x00000025, 6}, {0x00000026, 6}, {0x00000027, 6}, {0x00000006, 5}, {0x00000074, 7}, {0x00000075, 7}, {0x00000028, 6}, {0x00000029, 6}, {0x0000002a, 6}, {0x00000007, 5}, {0x0000002b, 6}, {0x00000076, 7}, {0x0000002c, 6}, {0x00000008, 5}, {0x00000009, 5}, {0x0000002d, 6}, {0x00000077, 7}, {0x00000078, 7}, {0x00000079, 7}, {0x0000007a, 7}, {0x0000007b, 7}, {0x00007ffe, 15}, {0x000007fc, 11}, {0x00003ffd, 14}, {0x00001ffd, 13}, {0x0ffffffc, 28}, {0x000fffe6, 20}, {0x003fffd2, 22}, {0x000fffe7, 20}, {0x000fffe8, 20}, {0x003fffd3, 22}, {0x003fffd4, 22}, {0x003fffd5, 22}, {0x007fffd9, 23}, {0x003fffd6, 22}, {0x007fffda, 23}, {0x007fffdb, 23}, {0x007fffdc, 23}, {0x007fffdd, 23}, {0x007fffde, 23}, {0x00ffffeb, 24}, {0x007fffdf, 23}, {0x00ffffec, 24}, {0x00ffffed, 24}, {0x003fffd7, 22}, {0x007fffe0, 23}, {0x00ffffee, 24}, {0x007fffe1, 23}, {0x007fffe2, 23}, {0x007fffe3, 23}, {0x007fffe4, 23}, {0x001fffdc, 21}, {0x003fffd8, 22}, {0x007fffe5, 23}, {0x003fffd9, 22}, {0x007fffe6, 23}, {0x007fffe7, 23}, {0x00ffffef, 24}, {0x003fffda, 22}, {0x001fffdd, 21}, {0x000fffe9, 20}, {0x003fffdb, 22}, {0x003fffdc, 22}, {0x007fffe8, 23}, {0x007fffe9, 23}, {0x001fffde, 21}, {0x007fffea, 23}, {0x003fffdd, 22}, {0x003fffde, 22}, {0x00fffff0, 24}, {0x001fffdf, 21}, {0x003fffdf, 22}, {0x007fffeb, 23}, {0x007fffec, 23}, {0x001fffe0, 21}, {0x001fffe1, 21}, {0x003fffe0, 22}, {0x001fffe2, 21}, {0x007fffed, 23}, {0x003fffe1, 22}, {0x007fffee, 23}, {0x007fffef, 23}, {0x000fffea, 20}, {0x003fffe2, 22}, {0x003fffe3, 22}, {0x003fffe4, 22}, {0x007ffff0, 23}, {0x003fffe5, 22}, {0x003fffe6, 22}, {0x007ffff1, 23}, {0x03ffffe0, 26}, {0x03ffffe1, 26}, {0x000fffeb, 20}, {0x0007fff1, 19}, {0x003fffe7, 22}, {0x007ffff2, 23}, {0x003fffe8, 22}, {0x01ffffec, 25}, {0x03ffffe2, 26}, {0x03ffffe3, 26}, {0x03ffffe4, 26}, {0x07ffffde, 27}, {0x07ffffdf, 27}, {0x03ffffe5, 26}, {0x00fffff1, 24}, {0x01ffffed, 25}, {0x0007fff2, 19}, {0x001fffe3, 21}, {0x03ffffe6, 26}, {0x07ffffe0, 27}, {0x07ffffe1, 27}, {0x03ffffe7, 26}, {0x07ffffe2, 27}, {0x00fffff2, 24}, {0x001fffe4, 21}, {0x001fffe5, 21}, {0x03ffffe8, 26}, {0x03ffffe9, 26}, {0x0ffffffd, 28}, {0x07ffffe3, 27}, {0x07ffffe4, 27}, {0x07ffffe5, 27}, {0x000fffec, 20}, {0x00fffff3, 24}, {0x000fffed, 20}, {0x001fffe6, 21}, {0x003fffe9, 22}, {0x001fffe7, 21}, {0x001fffe8, 21}, {0x007ffff3, 23}, {0x003fffea, 22}, {0x003fffeb, 22}, {0x01ffffee, 25}, {0x01ffffef, 25}, {0x00fffff4, 24}, {0x00fffff5, 24}, {0x03ffffea, 26}, {0x007ffff4, 23}, {0x03ffffeb, 26}, {0x07ffffe6, 27}, {0x03ffffec, 26}, {0x03ffffed, 26}, {0x07ffffe7, 27}, {0x07ffffe8, 27}, {0x07ffffe9, 27}, {0x07ffffea, 27}, {0x07ffffeb, 27}, {0x0ffffffe, 28}, {0x07ffffec, 27}, {0x07ffffed, 27}, {0x07ffffee, 27}, {0x07ffffef, 27}, {0x07fffff0, 27}, {0x03ffffee, 26} }; /* same as above, but embeds lowercase transformation */ static ngx_http_huff_encode_code_t ngx_http_huff_encode_table_lc[256] = { {0x00001ff8, 13}, {0x007fffd8, 23}, {0x0fffffe2, 28}, {0x0fffffe3, 28}, {0x0fffffe4, 28}, {0x0fffffe5, 28}, {0x0fffffe6, 28}, {0x0fffffe7, 28}, {0x0fffffe8, 28}, {0x00ffffea, 24}, {0x3ffffffc, 30}, {0x0fffffe9, 28}, {0x0fffffea, 28}, {0x3ffffffd, 30}, {0x0fffffeb, 28}, {0x0fffffec, 28}, {0x0fffffed, 28}, {0x0fffffee, 28}, {0x0fffffef, 28}, {0x0ffffff0, 28}, {0x0ffffff1, 28}, {0x0ffffff2, 28}, {0x3ffffffe, 30}, {0x0ffffff3, 28}, {0x0ffffff4, 28}, {0x0ffffff5, 28}, {0x0ffffff6, 28}, {0x0ffffff7, 28}, {0x0ffffff8, 28}, {0x0ffffff9, 28}, {0x0ffffffa, 28}, {0x0ffffffb, 28}, {0x00000014, 6}, {0x000003f8, 10}, {0x000003f9, 10}, {0x00000ffa, 12}, {0x00001ff9, 13}, {0x00000015, 6}, {0x000000f8, 8}, {0x000007fa, 11}, {0x000003fa, 10}, {0x000003fb, 10}, {0x000000f9, 8}, {0x000007fb, 11}, {0x000000fa, 8}, {0x00000016, 6}, {0x00000017, 6}, {0x00000018, 6}, {0x00000000, 5}, {0x00000001, 5}, {0x00000002, 5}, {0x00000019, 6}, {0x0000001a, 6}, {0x0000001b, 6}, {0x0000001c, 6}, {0x0000001d, 6}, {0x0000001e, 6}, {0x0000001f, 6}, {0x0000005c, 7}, {0x000000fb, 8}, {0x00007ffc, 15}, {0x00000020, 6}, {0x00000ffb, 12}, {0x000003fc, 10}, {0x00001ffa, 13}, {0x00000003, 5}, {0x00000023, 6}, {0x00000004, 5}, {0x00000024, 6}, {0x00000005, 5}, {0x00000025, 6}, {0x00000026, 6}, {0x00000027, 6}, {0x00000006, 5}, {0x00000074, 7}, {0x00000075, 7}, {0x00000028, 6}, {0x00000029, 6}, {0x0000002a, 6}, {0x00000007, 5}, {0x0000002b, 6}, {0x00000076, 7}, {0x0000002c, 6}, {0x00000008, 5}, {0x00000009, 5}, {0x0000002d, 6}, {0x00000077, 7}, {0x00000078, 7}, {0x00000079, 7}, {0x0000007a, 7}, {0x0000007b, 7}, {0x00001ffb, 13}, {0x0007fff0, 19}, {0x00001ffc, 13}, {0x00003ffc, 14}, {0x00000022, 6}, {0x00007ffd, 15}, {0x00000003, 5}, {0x00000023, 6}, {0x00000004, 5}, {0x00000024, 6}, {0x00000005, 5}, {0x00000025, 6}, {0x00000026, 6}, {0x00000027, 6}, {0x00000006, 5}, {0x00000074, 7}, {0x00000075, 7}, {0x00000028, 6}, {0x00000029, 6}, {0x0000002a, 6}, {0x00000007, 5}, {0x0000002b, 6}, {0x00000076, 7}, {0x0000002c, 6}, {0x00000008, 5}, {0x00000009, 5}, {0x0000002d, 6}, {0x00000077, 7}, {0x00000078, 7}, {0x00000079, 7}, {0x0000007a, 7}, {0x0000007b, 7}, {0x00007ffe, 15}, {0x000007fc, 11}, {0x00003ffd, 14}, {0x00001ffd, 13}, {0x0ffffffc, 28}, {0x000fffe6, 20}, {0x003fffd2, 22}, {0x000fffe7, 20}, {0x000fffe8, 20}, {0x003fffd3, 22}, {0x003fffd4, 22}, {0x003fffd5, 22}, {0x007fffd9, 23}, {0x003fffd6, 22}, {0x007fffda, 23}, {0x007fffdb, 23}, {0x007fffdc, 23}, {0x007fffdd, 23}, {0x007fffde, 23}, {0x00ffffeb, 24}, {0x007fffdf, 23}, {0x00ffffec, 24}, {0x00ffffed, 24}, {0x003fffd7, 22}, {0x007fffe0, 23}, {0x00ffffee, 24}, {0x007fffe1, 23}, {0x007fffe2, 23}, {0x007fffe3, 23}, {0x007fffe4, 23}, {0x001fffdc, 21}, {0x003fffd8, 22}, {0x007fffe5, 23}, {0x003fffd9, 22}, {0x007fffe6, 23}, {0x007fffe7, 23}, {0x00ffffef, 24}, {0x003fffda, 22}, {0x001fffdd, 21}, {0x000fffe9, 20}, {0x003fffdb, 22}, {0x003fffdc, 22}, {0x007fffe8, 23}, {0x007fffe9, 23}, {0x001fffde, 21}, {0x007fffea, 23}, {0x003fffdd, 22}, {0x003fffde, 22}, {0x00fffff0, 24}, {0x001fffdf, 21}, {0x003fffdf, 22}, {0x007fffeb, 23}, {0x007fffec, 23}, {0x001fffe0, 21}, {0x001fffe1, 21}, {0x003fffe0, 22}, {0x001fffe2, 21}, {0x007fffed, 23}, {0x003fffe1, 22}, {0x007fffee, 23}, {0x007fffef, 23}, {0x000fffea, 20}, {0x003fffe2, 22}, {0x003fffe3, 22}, {0x003fffe4, 22}, {0x007ffff0, 23}, {0x003fffe5, 22}, {0x003fffe6, 22}, {0x007ffff1, 23}, {0x03ffffe0, 26}, {0x03ffffe1, 26}, {0x000fffeb, 20}, {0x0007fff1, 19}, {0x003fffe7, 22}, {0x007ffff2, 23}, {0x003fffe8, 22}, {0x01ffffec, 25}, {0x03ffffe2, 26}, {0x03ffffe3, 26}, {0x03ffffe4, 26}, {0x07ffffde, 27}, {0x07ffffdf, 27}, {0x03ffffe5, 26}, {0x00fffff1, 24}, {0x01ffffed, 25}, {0x0007fff2, 19}, {0x001fffe3, 21}, {0x03ffffe6, 26}, {0x07ffffe0, 27}, {0x07ffffe1, 27}, {0x03ffffe7, 26}, {0x07ffffe2, 27}, {0x00fffff2, 24}, {0x001fffe4, 21}, {0x001fffe5, 21}, {0x03ffffe8, 26}, {0x03ffffe9, 26}, {0x0ffffffd, 28}, {0x07ffffe3, 27}, {0x07ffffe4, 27}, {0x07ffffe5, 27}, {0x000fffec, 20}, {0x00fffff3, 24}, {0x000fffed, 20}, {0x001fffe6, 21}, {0x003fffe9, 22}, {0x001fffe7, 21}, {0x001fffe8, 21}, {0x007ffff3, 23}, {0x003fffea, 22}, {0x003fffeb, 22}, {0x01ffffee, 25}, {0x01ffffef, 25}, {0x00fffff4, 24}, {0x00fffff5, 24}, {0x03ffffea, 26}, {0x007ffff4, 23}, {0x03ffffeb, 26}, {0x07ffffe6, 27}, {0x03ffffec, 26}, {0x03ffffed, 26}, {0x07ffffe7, 27}, {0x07ffffe8, 27}, {0x07ffffe9, 27}, {0x07ffffea, 27}, {0x07ffffeb, 27}, {0x0ffffffe, 28}, {0x07ffffec, 27}, {0x07ffffed, 27}, {0x07ffffee, 27}, {0x07ffffef, 27}, {0x07fffff0, 27}, {0x03ffffee, 26} }; #if (NGX_PTR_SIZE == 8) #if (NGX_HAVE_LITTLE_ENDIAN) #if (NGX_HAVE_GCC_BSWAP64) #define ngx_http_huff_encode_buf(dst, buf) \ (*(uint64_t *) (dst) = __builtin_bswap64(buf)) #else #define ngx_http_huff_encode_buf(dst, buf) \ ((dst)[0] = (u_char) ((buf) >> 56), \ (dst)[1] = (u_char) ((buf) >> 48), \ (dst)[2] = (u_char) ((buf) >> 40), \ (dst)[3] = (u_char) ((buf) >> 32), \ (dst)[4] = (u_char) ((buf) >> 24), \ (dst)[5] = (u_char) ((buf) >> 16), \ (dst)[6] = (u_char) ((buf) >> 8), \ (dst)[7] = (u_char) (buf)) #endif #else /* !NGX_HAVE_LITTLE_ENDIAN */ #define ngx_http_huff_encode_buf(dst, buf) \ (*(uint64_t *) (dst) = (buf)) #endif #else /* NGX_PTR_SIZE == 4 */ #define ngx_http_huff_encode_buf(dst, buf) \ (*(uint32_t *) (dst) = htonl(buf)) #endif size_t ngx_http_huff_encode(u_char *src, size_t len, u_char *dst, ngx_uint_t lower) { u_char *end; size_t hlen; ngx_uint_t buf, pending, code; ngx_http_huff_encode_code_t *table, *next; table = lower ? ngx_http_huff_encode_table_lc : ngx_http_huff_encode_table; hlen = 0; buf = 0; pending = 0; end = src + len; while (src != end) { next = &table[*src++]; code = next->code; pending += next->len; /* accumulate bits */ if (pending < sizeof(buf) * 8) { buf |= code << (sizeof(buf) * 8 - pending); continue; } if (hlen + sizeof(buf) >= len) { return 0; } pending -= sizeof(buf) * 8; buf |= code >> pending; ngx_http_huff_encode_buf(&dst[hlen], buf); hlen += sizeof(buf); buf = pending ? code << (sizeof(buf) * 8 - pending) : 0; } if (pending == 0) { return hlen; } buf |= (ngx_uint_t) -1 >> pending; pending = ngx_align(pending, 8); if (hlen + pending / 8 >= len) { return 0; } buf >>= sizeof(buf) * 8 - pending; do { pending -= 8; dst[hlen++] = (u_char) (buf >> pending); } while (pending); return hlen; }