1berry/ruby
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

io.c (read_all): grow the buffer exponentially when size is unknown

Browse Source 
[Feature #6047]

Currently it's grown by `BUFSIZ` (1024) on every iteration which is bit wasteful.
Instead we can double the capacity whenever there is less than `BUFSIZ` capacity
left.
This commit is contained in:
Jean Boussier 2022-11-29 10:39:56 +01:00 committed by Jean Boussier
parent 07ac707758
commit 7390eb43fe
Notes: git 2022-12-02 08:54:22 +00:00 
Merged: https://github.com/ruby/ruby/pull/6829
1 changed files with 16 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
io.c
View File

@ -167,6 +167,8 @@ off_t __syscall(quad_t number, ...);
#define IO_RBUF_CAPA_FOR(fptr) (NEED_READCONV(fptr) ? IO_CBUF_CAPA_MIN : IO_RBUF_CAPA_MIN) #define IO_RBUF_CAPA_FOR(fptr) (NEED_READCONV(fptr) ? IO_CBUF_CAPA_MIN : IO_RBUF_CAPA_MIN)
#define IO_WBUF_CAPA_MIN 8192 #define IO_WBUF_CAPA_MIN 8192
#define IO_MAX_BUFFER_GROWTH 8 * 1024 * 1024 // 8MB
/* define system APIs */ /* define system APIs */
#ifdef _WIN32 #ifdef _WIN32
#undef open #undef open
@ -3244,7 +3246,9 @@ io_setstrbuf(VALUE *str, long len)
} }
len -= clen; len -= clen;
} }
if ((rb_str_capacity(*str) - (size_t)RSTRING_LEN(*str)) < (size_t)len) {
rb_str_modify_expand(*str, len); rb_str_modify_expand(*str, len);
}
return FALSE; return FALSE;
} }
@ -3327,7 +3331,17 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
pos += rb_str_coderange_scan_restartable(RSTRING_PTR(str) + pos, RSTRING_PTR(str) + bytes, enc, &cr); pos += rb_str_coderange_scan_restartable(RSTRING_PTR(str) + pos, RSTRING_PTR(str) + bytes, enc, &cr);
if (bytes < siz) break; if (bytes < siz) break;
siz += BUFSIZ; siz += BUFSIZ;
rb_str_modify_expand(str, BUFSIZ);
size_t capa = rb_str_capacity(str);
if (capa < (size_t)RSTRING_LEN(str) + BUFSIZ) {
if (capa < BUFSIZ) {
capa = BUFSIZ;
}
else if (capa > IO_MAX_BUFFER_GROWTH) {
capa = IO_MAX_BUFFER_GROWTH;
}
rb_str_modify_expand(str, capa);
}
} }
if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str)); if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str));
str = io_enc_str(str, fptr); str = io_enc_str(str, fptr);