简单易用的 高性能 C 语言 动态字串。基本特性：
- 简单易用的 API
- 极高的格式化效率 (使用 stb_snprintf 1.06)
- 自动创建字串
- 对于基本操作 API， SDS 一般返回新的 动态字串 handle，estr 则返回 写入的长度
- SDS 传入的 handle 为 handle 本身， estr API 一般传入 handle 的指针
- 核心部分来自 redis SDS
- 格式化部分来自 stb_snprintf.c
关于 stb_snprintf.c 本项目内部做了相关修改，添加了一些宏开关，用以取消一些优化，因为那些优化在现今来看效率并不高，特别是关于 字串拷贝 这一部分，现在的 memcpy 内部使用了更优的指令集，具有更高的效率
static int estr_basic_api_tutorial()
{
estr s = 0; // init from 0 or null
//
// wrt API always write from the beginning
// cat API write continued
//
estr_wrtS(s, "Hello" ); puts(s); // Hello
estr_catS(s, ", estr"); puts(s); // Hello, estr
estr_wrtS(s, "clear" ); puts(s); // clear
// or you can show the detail of estr
estr_show(s); // (estr: e08 5/22):[clear] // 5 is len, 22 is cap
puts("----");
// basic API // DATA NOTE
estr_wrtS(s, "str"); estr_show(s); // [str] write cstr
estr_wrtB(s, "123\0567", 7); estr_show(s); // [123\0567] write bin data
estr_wrtW(s, " wordd123"); estr_show(s); // [wordd] write a word
estr_wrtL(s, " line\nline2"); estr_show(s); // [ line] write a line
estr_wrtT(s, "abcde", 'e'); estr_show(s); // [abcd] write to the end char
estr_wrtP(s, "%s", "fmt"); estr_show(s); // [fmt] write fmt(like sprintf)
estr_wrtP(s, "%0*d", 4, 1); estr_show(s); // [0001] write fmt(like sprintf)
estr_wrtF(s, "%s", "efmt"); estr_show(s); // [efmt] write fmt(simple internal)
puts("----");
// free it after using it
estr_free(s);
s = 0; // you need to set s to 0 by you self if needed
estr_show(s);
return ETEST_OK;
}==================== OUTPUT ===================
Hello
Hello, estr
clear
(estr: e08 5/22):[clear]
----
(estr: e08 3/22):[str]
(estr: e08 7/22):[123.7 ]
(estr: e08 5/22):[wordd]
(estr: e08 5/22):[ line]
(estr: e08 4/22):[abcd]
(estr: e08 3/22):[fmt]
(estr: e08 4/22):[0001]
(estr: e08 4/22):[efmt]
----
(estr: nullptr)
estr 的基本操作 API 主要有 两部分，wrt 和 cat，例如：
estr_wrtS()
estr_catS()
其中 wrt 表示重写，cat 表示追加
基本操作和用法请查看 快速入门
estr 为动态创建版，当传入的 estr 空间不足时，会自动分配新的空间进行写入，所以对于 estr 的 API，大部分实际上传入的是 estr 指针，当发生 realloc 时，自动更新 estr；
sstr 为另一个版本，s 意为 safe 或 stack using，它不会自动分配新空间，当空间不足时，不进行写入，返回一个 负值，表示写入失败。
sstr 不会分配新空间，有两种方式可以使用它：
-
直接使用 estr 的 handle
{ estr e = estr_new(4); estr_show(e); sstr_wrtS(e, "12345678"); estr_show(e); // will write failed sstr_wrtS(e, "1234"); estr_show(e); // will write ok estr_free(e); }==================== OUTPUT =================== (estr: e08 0/4):[] (estr: e08 0/4):[] (estr: e08 4/4):[1234] -
使用一个 buf 初始化 sstr
{ char buf[16]; // buf 头部有一部分会被内部使用 sstr s = sstr_init(buf, 8); estr_show(s); sstr_wrtS(s, "12345678"); estr_show(s); // will write failed sstr_wrtS(s, "1234"); estr_show(s); // will write ok }==================== OUTPUT =================== (sstr: e08 0/4):[] (sstr: e08 0/4):[] (sstr: e08 4/4):[1234]
因为 estr 内部格式化部分使用的就是 stb_sprintf，所以理论上来说 estr 的效率不可能比 stb_sprintf 还高，estr 内部已经尽量减少其它操作带来的影响
==================== EBENCHMARK =====================
estr_wrtP
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 24.07ms 48.15ns 20769294.67
%s(4096) 500000 4095 88.83ms 177.67ns 5628475.58
%d 500000 10 20.45ms 40.90ns 24452269.17
%ld(10) 500000 14 21.56ms 43.13ns 23186792.80
%ld(19) 500000 23 26.40ms 52.81ns 18937241.98
%.2f 500000 5 44.52ms 89.05ns 11229898.48
%.32f 500000 158 65.52ms 131.03ns 7631723.55
==================== EBENCHMARK =====================
sstr_wrtP
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 18.02ms 36.04ns 27748487.71
%s(4096) 500000 4095 85.73ms 171.46ns 5832400.15
%d 500000 10 19.44ms 38.88ns 25718841.62
%ld(10) 500000 14 21.06ms 42.12ns 23739435.95
%ld(19) 500000 23 24.87ms 49.74ns 20104543.63
%.2f 500000 5 43.41ms 86.82ns 11518614.08
%.32f 500000 158 61.44ms 122.88ns 8138285.75
==================== EBENCHMARK =====================
estr_wrtF
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 14.60ms 29.20ns 34241884.67
%s(4096) 500000 4095 86.83ms 173.66ns 5758444.76
%S(10) 500000 14 13.96ms 27.92ns 35811488.33
%S(4096) 500000 4095 35.49ms 70.98ns 14089269.61
%i(10) 500000 14 21.72ms 43.44ns 23020257.83
%I(19) 500000 23 30.74ms 61.48ns 16264923.07
==================== EBENCHMARK =====================
sprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 35.78ms 71.57ns 13972334.78
%s(4096) 500000 4095 112.69ms 225.37ns 4437108.43
%d 500000 10 38.10ms 76.19ns 13124393.00
%ld(10) 500000 14 44.43ms 88.85ns 11254670.69
%ld(19) 500000 23 52.84ms 105.67ns 9463423.87
%.2f 500000 5 70.57ms 141.15ns 7084762.09
%.32f 500000 158 2228.97ms 4457.94ns 224318.76
==================== EBENCHMARK =====================
snprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 35.76ms 71.52ns 13981711.92
%s(4096) 500000 4095 110.88ms 221.76ns 4509298.17
%d 500000 10 37.94ms 75.88ns 13178008.54
%ld(10) 500000 14 44.15ms 88.30ns 11324771.81
%ld(19) 500000 23 53.28ms 106.56ns 9384384.38
%.2f 500000 5 70.25ms 140.49ns 7117843.01
%.32f 500000 158 2254.69ms 4509.38ns 221760.17
==================== EBENCHMARK =====================
stbsp_sprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 15.82ms 31.64ns 31605562.58
%s(4096) 500000 4095 428.77ms 857.53ns 1166137.24
%d 500000 10 15.84ms 31.68ns 31565656.57
%ld(10) 500000 14 17.17ms 34.35ns 29115471.96
%ld(19) 500000 23 21.87ms 43.74ns 22864459.48
%.2f 500000 5 38.98ms 77.96ns 12826761.76
%.32f 500000 158 58.33ms 116.65ns 8572359.28
==================== EBENCHMARK =====================
stbsp_snprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 25.89ms 51.77ns 19316206.30
%s(4096) 500000 4095 449.58ms 899.16ns 1112149.12
%d 500000 10 16.77ms 33.55ns 29808036.25
%ld(10) 500000 14 19.07ms 38.13ns 26226068.71
%ld(19) 500000 23 22.85ms 45.69ns 21885669.26
%.2f 500000 5 40.24ms 80.48ns 12424829.78
%.32f 500000 158 63.19ms 126.39ns 7912143.56
==================== EBENCHMARK =====================
estr_wrtP
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 21.44ms 42.89ns 23318065.60
%s(4096) 500000 4095 99.51ms 199.03ns 5024373.69
%d 500000 10 19.35ms 38.71ns 25835630.21
%ld(10) 500000 14 22.31ms 44.61ns 22415936.76
%ld(19) 500000 23 30.40ms 60.81ns 16445004.99
%.2f 500000 5 66.81ms 133.61ns 7484272.33
%.32f 500000 158 101.95ms 203.90ns 4904422.23
==================== EBENCHMARK =====================
sstr_wrtP
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 15.53ms 31.06ns 32191815.84
%s(4096) 500000 4095 90.78ms 181.56ns 5507822.99
%d 500000 10 18.83ms 37.66ns 26555329.73
%ld(10) 500000 14 20.72ms 41.44ns 24129512.16
%ld(19) 500000 23 28.67ms 57.34ns 17438440.91
%.2f 500000 5 65.42ms 130.83ns 7643452.39
%.32f 500000 158 96.46ms 192.91ns 5183656.54
==================== EBENCHMARK =====================
estr_wrtF
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 12.28ms 24.56ns 40709113.68
%s(4096) 500000 4095 88.85ms 177.70ns 5627357.76
%S(10) 500000 14 10.48ms 20.97ns 47693854.29
%S(4096) 500000 4095 49.66ms 99.31ns 10069248.64
%i(10) 500000 14 18.82ms 37.64ns 26568006.55
%I(19) 500000 23 28.50ms 56.99ns 17546653.57
==================== EBENCHMARK =====================
sprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 38.90ms 77.81ns 12851917.96
%s(4096) 500000 4095 1265.61ms 2531.23ns 395064.94
%d 500000 10 35.34ms 70.69ns 14147086.58
%ld(10) 500000 14 38.06ms 76.11ns 13138362.14
%ld(19) 500000 23 45.77ms 91.53ns 10925354.59
%.2f 500000 5 155.75ms 311.49ns 3210369.36
%.32f 500000 158 3298.29ms 6596.57ns 151593.87
==================== EBENCHMARK =====================
snprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 43.52ms 87.03ns 11489859.52
%s(4096) 500000 4095 1239.15ms 2478.31ns 403501.22
%d 500000 10 35.97ms 71.93ns 13901610.02
%ld(10) 500000 14 37.68ms 75.37ns 13268293.93
%ld(19) 500000 23 48.07ms 96.15ns 10400710.46
%.2f 500000 5 157.41ms 314.81ns 3176516.99
%.32f 500000 158 3291.72ms 6583.45ns 151896.10
==================== EBENCHMARK =====================
stbsp_sprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 15.57ms 31.15ns 32103798.52
%s(4096) 500000 4095 566.33ms 1132.66ns 882874.86
%d 500000 10 14.51ms 29.02ns 34453138.43
%ld(10) 500000 14 17.52ms 35.03ns 28543625.45
%ld(19) 500000 23 23.31ms 46.63ns 21447254.74
%.2f 500000 5 65.18ms 130.36ns 7670974.24
%.32f 500000 158 101.44ms 202.88ns 4928947.79
==================== EBENCHMARK =====================
stbsp_snprintf
=====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- --------- --------- -----------
%s(10) 500000 14 18.65ms 37.30ns 26809943.29
%s(4096) 500000 4095 596.73ms 1193.47ns 837895.10
%d 500000 10 18.26ms 36.52ns 27385617.26
%ld(10) 500000 14 20.86ms 41.73ns 23963817.70
%ld(19) 500000 23 29.30ms 58.59ns 17066376.57
%.2f 500000 5 67.41ms 134.82ns 7417306.82
%.32f 500000 158 105.06ms 210.13ns 4759058.84
==================== EBENCHMARK ====================
estr_wrtP
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 22.00ms 44.00ns 22727479.34
%s(4096) 500000 4095 134.00ms 268.00ns 3731359.99
%d 500000 10 18.15ms 36.29ns 27552915.37
%ld(10) 500000 14 21.93ms 43.86ns 22799401.74
%ld(19) 500000 14 21.09ms 42.17ns 23713203.04
%.2f 500000 5 47.01ms 94.01ns 10636736.31
%.32f 500000 158 79.93ms 159.86ns 6255481.37
==================== EBENCHMARK ====================
sstr_wrtP
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 17.96ms 35.92ns 27840883.78
%s(4096) 500000 4095 126.10ms 252.21ns 3964997.01
%d 500000 10 17.86ms 35.72ns 27997872.16
%ld(10) 500000 14 22.15ms 44.30ns 22574892.20
%ld(19) 500000 14 20.97ms 41.93ns 23847680.10
%.2f 500000 5 45.02ms 90.04ns 11105607.67
%.32f 500000 158 78.85ms 157.70ns 6340993.25
==================== EBENCHMARK ====================
estr_wrtF
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 15.00ms 30.00ns 33338667.52
%s(4096) 500000 4095 143.15ms 286.30ns 3492883.60
%S(10) 500000 14 14.02ms 28.03ns 35671225.45
%S(4096) 500000 4095 59.98ms 119.96ns 8336139.83
%i(10) 500000 14 19.00ms 38.00ns 26315096.97
%I(19) 500000 23 27.17ms 54.33ns 18404478.91
==================== EBENCHMARK ====================
sprintf
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 50.01ms 100.02ns 9997760.50
%s(4096) 500000 4095 151.13ms 302.26ns 3308385.90
%d 500000 10 73.12ms 146.23ns 6838429.79
%ld(10) 500000 14 84.12ms 168.24ns 5943847.29
%ld(19) 500000 14 84.08ms 168.16ns 5946781.07
%.2f 500000 5 141.15ms 282.29ns 3542403.63
%.32f 500000 158 799.14ms 1598.29ns 625668.68
==================== EBENCHMARK ====================
snprintf
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 48.00ms 95.99ns 10417252.64
%s(4096) 500000 4095 154.01ms 308.02ns 3246504.49
%d 500000 10 75.00ms 150.00ns 6666666.67
%ld(10) 500000 14 92.15ms 184.31ns 5425729.90
%ld(19) 500000 14 97.13ms 194.26ns 5147724.24
%.2f 500000 5 149.15ms 298.30ns 3352372.57
%.32f 500000 158 810.08ms 1620.16ns 617221.70
==================== EBENCHMARK ====================
stbsp_sprintf
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 15.13ms 30.25ns 33054354.58
%s(4096) 500000 4095 541.16ms 1082.32ns 923939.80
%d 500000 10 15.03ms 30.05ns 33276319.91
%ld(10) 500000 14 18.13ms 36.25ns 27584228.44
%ld(19) 500000 14 20.02ms 40.03ns 24980390.39
%.2f 500000 5 46.12ms 92.24ns 10840837.00
%.32f 500000 158 85.15ms 170.30ns 5871976.81
==================== EBENCHMARK ====================
stbsp_snprintf
====================================================
OPRT OPRTS SCALE COST TPO OPS
-------- ------ ----- -------- --------- -----------
%s(10) 500000 14 19.00ms 38.00ns 26317174.59
%s(4096) 500000 4095 554.14ms 1108.29ns 902291.57
%d 500000 10 17.97ms 35.94ns 27821829.01
%ld(10) 500000 14 20.14ms 40.28ns 24824244.35
%ld(19) 500000 14 20.00ms 40.00ns 25000250.00
%.2f 500000 5 44.15ms 88.29ns 11325772.25
%.32f 500000 158 87.90ms 175.80ns 5688340.38