io.c: shrink read buffer

* io.c (io_setstrbuf): return true if the buffer is newly created.

* io.c (io_set_read_length): shrink the read buffer if it is a new
  object and is too large.  [ruby-core:81370] [Bug #13597]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59701 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
nobu 2017-08-31 08:21:46 +00:00
parent bb03f02805
commit 9f1994ed5c
2 changed files with 47 additions and 19 deletions

58
io.c
View File

@ -2140,7 +2140,7 @@ io_bufread(char *ptr, long len, rb_io_t *fptr)
return len - n; return len - n;
} }
static void io_setstrbuf(VALUE *str, long len); static int io_setstrbuf(VALUE *str, long len);
struct bufread_arg { struct bufread_arg {
char *str_ptr; char *str_ptr;
@ -2359,33 +2359,45 @@ io_shift_cbuf(rb_io_t *fptr, int len, VALUE *strp)
return str; return str;
} }
static void static int
io_setstrbuf(VALUE *str, long len) io_setstrbuf(VALUE *str, long len)
{ {
#ifdef _WIN32 #ifdef _WIN32
len = (len + 1) & ~1L; /* round up for wide char */ len = (len + 1) & ~1L; /* round up for wide char */
#endif #endif
if (NIL_P(*str)) { if (NIL_P(*str)) {
*str = rb_str_new(0, 0); *str = rb_str_new(0, len);
return TRUE;
} }
else { else {
VALUE s = StringValue(*str); VALUE s = StringValue(*str);
long clen = RSTRING_LEN(s); long clen = RSTRING_LEN(s);
if (clen >= len) { if (clen >= len) {
rb_str_modify(s); rb_str_modify(s);
return; return FALSE;
} }
len -= clen; len -= clen;
} }
rb_str_modify_expand(*str, len); rb_str_modify_expand(*str, len);
return FALSE;
}
#define MAX_REALLOC_GAP 4096
static void
io_shrink_read_string(VALUE str, long n)
{
if (rb_str_capacity(str) - n > MAX_REALLOC_GAP) {
rb_str_resize(str, n);
}
} }
static void static void
io_set_read_length(VALUE str, long n) io_set_read_length(VALUE str, long n, int shrinkable)
{ {
if (RSTRING_LEN(str) != n) { if (RSTRING_LEN(str) != n) {
rb_str_modify(str); rb_str_modify(str);
rb_str_set_len(str, n); rb_str_set_len(str, n);
if (shrinkable) io_shrink_read_string(str, n);
} }
} }
@ -2397,11 +2409,12 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
long pos; long pos;
rb_encoding *enc; rb_encoding *enc;
int cr; int cr;
int shrinkable;
if (NEED_READCONV(fptr)) { if (NEED_READCONV(fptr)) {
int first = !NIL_P(str); int first = !NIL_P(str);
SET_BINARY_MODE(fptr); SET_BINARY_MODE(fptr);
io_setstrbuf(&str,0); shrinkable = io_setstrbuf(&str,0);
make_readconv(fptr, 0); make_readconv(fptr, 0);
while (1) { while (1) {
VALUE v; VALUE v;
@ -2420,6 +2433,7 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
if (v == MORE_CHAR_FINISHED) { if (v == MORE_CHAR_FINISHED) {
clear_readconv(fptr); clear_readconv(fptr);
if (first) rb_str_set_len(str, first = 0); if (first) rb_str_set_len(str, first = 0);
if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str));
return io_enc_str(str, fptr); return io_enc_str(str, fptr);
} }
} }
@ -2433,7 +2447,7 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
cr = 0; cr = 0;
if (siz == 0) siz = BUFSIZ; if (siz == 0) siz = BUFSIZ;
io_setstrbuf(&str,siz); shrinkable = io_setstrbuf(&str, siz);
for (;;) { for (;;) {
READ_CHECK(fptr); READ_CHECK(fptr);
n = io_fread(str, bytes, siz - bytes, fptr); n = io_fread(str, bytes, siz - bytes, fptr);
@ -2449,6 +2463,7 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
siz += BUFSIZ; siz += BUFSIZ;
rb_str_modify_expand(str, BUFSIZ); rb_str_modify_expand(str, BUFSIZ);
} }
if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str));
str = io_enc_str(str, fptr); str = io_enc_str(str, fptr);
ENC_CODERANGE_SET(str, cr); ENC_CODERANGE_SET(str, cr);
return str; return str;
@ -2511,6 +2526,7 @@ io_getpartial(int argc, VALUE *argv, VALUE io, VALUE opts, int nonblock)
VALUE length, str; VALUE length, str;
long n, len; long n, len;
struct read_internal_arg arg; struct read_internal_arg arg;
int shrinkable;
rb_scan_args(argc, argv, "11", &length, &str); rb_scan_args(argc, argv, "11", &length, &str);
@ -2518,7 +2534,7 @@ io_getpartial(int argc, VALUE *argv, VALUE io, VALUE opts, int nonblock)
rb_raise(rb_eArgError, "negative length %ld given", len); rb_raise(rb_eArgError, "negative length %ld given", len);
} }
io_setstrbuf(&str,len); shrinkable = io_setstrbuf(&str, len);
OBJ_TAINT(str); OBJ_TAINT(str);
GetOpenFile(io, fptr); GetOpenFile(io, fptr);
@ -2555,7 +2571,7 @@ io_getpartial(int argc, VALUE *argv, VALUE io, VALUE opts, int nonblock)
rb_syserr_fail_path(e, fptr->pathv); rb_syserr_fail_path(e, fptr->pathv);
} }
} }
io_set_read_length(str, n); io_set_read_length(str, n, shrinkable);
if (n == 0) if (n == 0)
return Qnil; return Qnil;
@ -2651,12 +2667,13 @@ io_read_nonblock(VALUE io, VALUE length, VALUE str, VALUE ex)
rb_io_t *fptr; rb_io_t *fptr;
long n, len; long n, len;
struct read_internal_arg arg; struct read_internal_arg arg;
int shrinkable;
if ((len = NUM2LONG(length)) < 0) { if ((len = NUM2LONG(length)) < 0) {
rb_raise(rb_eArgError, "negative length %ld given", len); rb_raise(rb_eArgError, "negative length %ld given", len);
} }
io_setstrbuf(&str,len); shrinkable = io_setstrbuf(&str, len);
OBJ_TAINT(str); OBJ_TAINT(str);
GetOpenFile(io, fptr); GetOpenFile(io, fptr);
rb_io_check_byte_readable(fptr); rb_io_check_byte_readable(fptr);
@ -2667,7 +2684,7 @@ io_read_nonblock(VALUE io, VALUE length, VALUE str, VALUE ex)
n = read_buffered_data(RSTRING_PTR(str), len, fptr); n = read_buffered_data(RSTRING_PTR(str), len, fptr);
if (n <= 0) { if (n <= 0) {
rb_io_set_nonblock(fptr); rb_io_set_nonblock(fptr);
io_setstrbuf(&str, len); shrinkable |= io_setstrbuf(&str, len);
arg.fd = fptr->fd; arg.fd = fptr->fd;
arg.str_ptr = RSTRING_PTR(str); arg.str_ptr = RSTRING_PTR(str);
arg.len = len; arg.len = len;
@ -2683,7 +2700,7 @@ io_read_nonblock(VALUE io, VALUE length, VALUE str, VALUE ex)
rb_syserr_fail_path(e, fptr->pathv); rb_syserr_fail_path(e, fptr->pathv);
} }
} }
io_set_read_length(str, n); io_set_read_length(str, n, shrinkable);
if (n == 0) { if (n == 0) {
if (ex == Qfalse) return Qnil; if (ex == Qfalse) return Qnil;
@ -2802,6 +2819,7 @@ io_read(int argc, VALUE *argv, VALUE io)
rb_io_t *fptr; rb_io_t *fptr;
long n, len; long n, len;
VALUE length, str; VALUE length, str;
int shrinkable;
#if defined(RUBY_TEST_CRLF_ENVIRONMENT) || defined(_WIN32) #if defined(RUBY_TEST_CRLF_ENVIRONMENT) || defined(_WIN32)
int previous_mode; int previous_mode;
#endif #endif
@ -2818,12 +2836,12 @@ io_read(int argc, VALUE *argv, VALUE io)
rb_raise(rb_eArgError, "negative length %ld given", len); rb_raise(rb_eArgError, "negative length %ld given", len);
} }
io_setstrbuf(&str,len); shrinkable = io_setstrbuf(&str,len);
GetOpenFile(io, fptr); GetOpenFile(io, fptr);
rb_io_check_byte_readable(fptr); rb_io_check_byte_readable(fptr);
if (len == 0) { if (len == 0) {
io_set_read_length(str, 0); io_set_read_length(str, 0, shrinkable);
return str; return str;
} }
@ -2832,7 +2850,7 @@ io_read(int argc, VALUE *argv, VALUE io)
previous_mode = set_binary_mode_with_seek_cur(fptr); previous_mode = set_binary_mode_with_seek_cur(fptr);
#endif #endif
n = io_fread(str, 0, len, fptr); n = io_fread(str, 0, len, fptr);
io_set_read_length(str, n); io_set_read_length(str, n, shrinkable);
#if defined(RUBY_TEST_CRLF_ENVIRONMENT) || defined(_WIN32) #if defined(RUBY_TEST_CRLF_ENVIRONMENT) || defined(_WIN32)
if (previous_mode == O_TEXT) { if (previous_mode == O_TEXT) {
setmode(fptr->fd, O_TEXT); setmode(fptr->fd, O_TEXT);
@ -4787,11 +4805,12 @@ rb_io_sysread(int argc, VALUE *argv, VALUE io)
rb_io_t *fptr; rb_io_t *fptr;
long n, ilen; long n, ilen;
struct read_internal_arg arg; struct read_internal_arg arg;
int shrinkable;
rb_scan_args(argc, argv, "11", &len, &str); rb_scan_args(argc, argv, "11", &len, &str);
ilen = NUM2LONG(len); ilen = NUM2LONG(len);
io_setstrbuf(&str,ilen); shrinkable = io_setstrbuf(&str, ilen);
if (ilen == 0) return str; if (ilen == 0) return str;
GetOpenFile(io, fptr); GetOpenFile(io, fptr);
@ -4823,7 +4842,7 @@ rb_io_sysread(int argc, VALUE *argv, VALUE io)
if (n == -1) { if (n == -1) {
rb_sys_fail_path(fptr->pathv); rb_sys_fail_path(fptr->pathv);
} }
io_set_read_length(str, n); io_set_read_length(str, n, shrinkable);
if (n == 0 && ilen > 0) { if (n == 0 && ilen > 0) {
rb_eof_error(); rb_eof_error();
} }
@ -4884,12 +4903,13 @@ rb_io_pread(int argc, VALUE *argv, VALUE io)
rb_io_t *fptr; rb_io_t *fptr;
ssize_t n; ssize_t n;
struct prdwr_internal_arg arg; struct prdwr_internal_arg arg;
int shrinkable;
rb_scan_args(argc, argv, "21", &len, &offset, &str); rb_scan_args(argc, argv, "21", &len, &offset, &str);
arg.count = NUM2SIZET(len); arg.count = NUM2SIZET(len);
arg.offset = NUM2OFFT(offset); arg.offset = NUM2OFFT(offset);
io_setstrbuf(&str, (long)arg.count); shrinkable = io_setstrbuf(&str, (long)arg.count);
if (arg.count == 0) return str; if (arg.count == 0) return str;
arg.buf = RSTRING_PTR(str); arg.buf = RSTRING_PTR(str);
@ -4905,7 +4925,7 @@ rb_io_pread(int argc, VALUE *argv, VALUE io)
if (n == -1) { if (n == -1) {
rb_sys_fail_path(fptr->pathv); rb_sys_fail_path(fptr->pathv);
} }
io_set_read_length(str, n); io_set_read_length(str, n, shrinkable);
if (n == 0 && arg.count > 0) { if (n == 0 && arg.count > 0) {
rb_eof_error(); rb_eof_error();
} }

View File

@ -29,4 +29,12 @@ class Test_StringCapacity < Test::Unit::TestCase
assert_equal("", String.new(capacity: -1000)) assert_equal("", String.new(capacity: -1000))
assert_equal(capa(String.new(capacity: -10000)), capa(String.new(capacity: -1000))) assert_equal(capa(String.new(capacity: -10000)), capa(String.new(capacity: -1000)))
end end
def test_io_read
s = String.new(capacity: 1000)
open(__FILE__) {|f|f.read(1024*1024, s)}
assert_equal(1024*1024, capa(s))
open(__FILE__) {|f|s = f.read(1024*1024)}
assert_operator(capa(s), :<=, s.bytesize+4096)
end
end end