[ruby-dev:26599] Re: SystemCallError.new("abc") => #<SystemCallError: unknown error - ab>

なかだです。

At Fri, 22 Jul 2005 00:43:09 +0900,
H.Yamamoto wrote in [ruby-dev:26597]:
> >それは環境を選びすぎでしょう。どこでもmissing/vsnprintf.cを使う
> >ようにするんであれば、出力部分を差し替えられるようにして
> >rb_str_cat()を呼ぶようにするという手もあります。

これを試してみました。

> 実際に計測してみると、vsnprintf(NULL, 0, .. の方法のほうが若干速いようなので、
> 使えるのなら使いたい気はするのです。ただ、この機能がない環境だと遅くなって
> しまうので、やはり受け入れにくいかもしれません。

missing/vsnprintf.cが単純な分なのか、やや速くなるようです。

$ time ./.i686-cygwin/miniruby.exe -e '100000.times{SystemCallError.new("abc")}'

real    0m1.260s
user    0m1.265s
sys     0m0.030s

$ time ./.i686-cygwin/miniruby.exe -e '100000.times{SystemCallError.new("abc")}'

real    0m1.207s
user    0m1.202s
sys     0m0.031s

intern.h, error.c, string.cの差分は省略。


Index: sprintf.c
===================================================================
RCS file: /cvs/ruby/src/ruby/sprintf.c,v
retrieving revision 1.46
diff -U2 -p -r1.46 sprintf.c
--- sprintf.c	7 Jun 2005 08:22:41 -0000	1.46
+++ sprintf.c	22 Jul 2005 06:33:28 -0000
@@ -16,4 +16,11 @@
 #include <ctype.h>
 #include <math.h>
+#ifdef HAVE_STDARG_PROTOTYPES
+#include <stdarg.h>
+#define va_init_list(a,b) va_start(a,b)
+#else
+#include <varargs.h>
+#define va_init_list(a,b) va_start(a)
+#endif
 
 #define BIT_DIGITS(N)   (((N)*146)/485 + 1)  /* log2(10) =~ 146/485 */
@@ -97,4 +104,10 @@ sign_bits(base, p)
 } while (0)
 
+#define FILL(c, l) do { \
+    CHECK(l);\
+    memset(&buf[blen], c, l);\
+    blen += (l);\
+} while (0)
+
 #define GETARG() (nextvalue != Qundef ? nextvalue : \
     posarg < 0 ? \
@@ -233,5 +246,13 @@ rb_f_sprintf(argc, argv)
     VALUE *argv;
 {
+    return rb_str_format(argc - 1, argv + 1, GETNTHARG(0));
+}
+
+VALUE
+rb_str_format(argc, argv, fmt)
+    int argc;
+    VALUE *argv;
     VALUE fmt;
+{
     const char *p, *end;
     char *buf;
@@ -247,5 +268,6 @@ rb_f_sprintf(argc, argv)
     VALUE str;
 
-    fmt = GETNTHARG(0);
+    ++argc;
+    --argv;
     if (OBJ_TAINTED(fmt)) tainted = 1;
     StringValue(fmt);
@@ -381,11 +403,12 @@ rb_f_sprintf(argc, argv)
 		char c;
 
-		if (!(flags & FMINUS))
-		    while (--width > 0)
-			PUSH(" ", 1);
 		c = NUM2INT(val) & 0xff;
-		PUSH(&c, 1);
-		while (--width > 0)
-		    PUSH(" ", 1);
+		if (!(flags & FWIDTH)) {
+		    PUSH(&c, 1);
+		}
+		else {
+		    FILL(' ', width);
+		    buf[blen - ((flags & FMINUS) ? width : 1)] = c;
+		}
 	    }
 	    break;
@@ -808,2 +831,80 @@ fmt_setup(buf, c, flags, width, prec)
     *buf = '\0';
 }
+
+#undef FILE
+#define FILE rb_printf_buffer
+#define __sbuf rb_printf_sbuf
+#define __sFILE rb_printf_sfile
+#undef feof
+#undef ferror
+#undef fileno
+#include "missing/vsnprintf.c"
+
+static int
+ruby__sfvwrite(fp, uio)
+    register rb_printf_buffer *fp;
+    register struct __suio *uio;
+{
+    struct __siov *iov;
+    VALUE result = (VALUE)fp->_bf._base;
+    char *buf = fp->_p;
+    size_t len, n;
+    int blen = buf - RSTRING(result)->ptr, bsiz = fp->_w;
+
+    if (RBASIC(result)->klass) {
+	rb_raise(rb_eRuntimeError, "rb_vsprintf reentered");
+    }
+    if ((len = uio->uio_resid) == 0)
+	return 0;
+    CHECK(len);
+    fp->_w = bsiz;
+    for (iov = uio->uio_iov; len > 0; ++iov) {
+	MEMCPY(buf, iov->iov_base, char, n = iov->iov_len);
+	buf += n;
+	len -= n;
+    }
+    fp->_p = (unsigned char *)buf;
+    return 0;
+}
+
+VALUE
+rb_vsprintf(fmt, ap)
+    const char *fmt;
+    va_list ap;
+{
+    rb_printf_buffer f;
+    VALUE result;
+
+    f._flags = __SWR | __SSTR;
+    f._bf._size = 0;
+    f._w = 120;
+    result = rb_str_buf_new(f._w);
+    f._bf._base = (unsigned char *)result;
+    f._p = (unsigned char *)RSTRING(result)->ptr;
+    RBASIC(result)->klass = 0;
+    f.vwrite = ruby__sfvwrite;
+    BSD_vfprintf(&f, fmt, ap);
+    RBASIC(result)->klass = rb_cString;
+    rb_str_resize(result, (char *)f._p - RSTRING(result)->ptr);
+
+    return result;
+}
+
+VALUE
+#ifdef HAVE_STDARG_PROTOTYPES
+rb_sprintf(const char *format, ...)
+#else
+ruby_sprintf(format, va_alist)
+    const char *format;
+    va_dcl
+#endif
+{
+    VALUE result;
+    va_list ap;
+
+    va_init_list(ap, format);
+    result = rb_vsprintf(format, ap);
+    va_end(ap);
+
+    return result;
+}
Index: missing/vsnprintf.c
===================================================================
RCS file: /cvs/ruby/src/ruby/missing/vsnprintf.c,v
retrieving revision 1.8
diff -U2 -p -r1.8 vsnprintf.c
--- missing/vsnprintf.c	1 Jul 2005 03:24:49 -0000	1.8
+++ missing/vsnprintf.c	22 Jul 2005 06:00:02 -0000
@@ -66,6 +66,12 @@
 #define u_int unsigned int
 
-#undef __P
+#if !defined(HAVE_STDARG_PROTOTYPES)
 #if defined(__STDC__)
+#define HAVE_STDARG_PROTOTYPES 1
+#endif
+#endif
+
+#undef __P
+#if defined(HAVE_STDARG_PROTOTYPES)
 # include <stdarg.h>
 # if !defined(__P)
@@ -152,5 +158,7 @@ struct __sbuf {
 typedef	struct __sFILE {
 	unsigned char *_p;	/* current position in (some) buffer */
+#if 0
 	int	_r;		/* read space left for getc() */
+#endif
 	int	_w;		/* write space left for putc() */
 	short	_flags;		/* flags, below; this FILE is free if 0 */
@@ -158,4 +166,5 @@ typedef	struct __sFILE {
 	struct	__sbuf _bf;	/* the buffer (at least 1 byte, if !NULL) */
 	int	_lbfsize;	/* 0 or -_bf._size, for inline putc */
+	int	(*vwrite)(/* struct __sFILE*, struct __suio * */);
 } FILE;
 
@@ -674,8 +683,7 @@ reswitch:	switch (ch) {
 					sign = '-';
 				}
-			} else {
-#else /* _HAVE_SANE_QUAD_ */
-			{
+			} else
 #endif /* _HAVE_SANE_QUAD_ */
+			{
 				ulval = SARG();
 				if ((long)ulval < 0) {
@@ -1084,4 +1092,5 @@ vsnprintf(str, n, fmt, ap)
 	f._bf._base = f._p = (unsigned char *)str;
 	f._bf._size = f._w = n - 1;
+	f.vwrite = BSD__sfvwrite;
 	ret = BSD_vfprintf(&f, fmt, ap);
 	*f._p = 0;
@@ -1093,12 +1102,6 @@ static char sccsid[] = "@(#)snprintf.c	8
 #endif /* LIBC_SCCS and not lint */
 
-#if defined(__STDC__)
-# include <stdarg.h>
-#else
-# include <varargs.h>
-#endif
-
 int
-#if defined(__STDC__)
+#if defined(HAVE_STDARG_PROTOTYPES)
 snprintf(char *str, size_t n, char const *fmt, ...)
 #else
@@ -1116,5 +1119,5 @@ va_dcl
 		return (EOF);
 
-#if defined(__STDC__)
+#if defined(HAVE_STDARG_PROTOTYPES)
 	va_start(ap, fmt);
 #else
@@ -1124,4 +1127,5 @@ va_dcl
 	f._bf._base = f._p = (unsigned char *)str;
 	f._bf._size = f._w = n - 1;
+	f.vwrite = BSD__sfvwrite;
 	ret = BSD_vfprintf(&f, fmt, ap);
 	*f._p = 0;
Index: win32/win32.c
===================================================================
RCS file: /cvs/ruby/src/ruby/win32/win32.c,v
retrieving revision 1.160
diff -U2 -p -r1.160 win32.c
--- win32/win32.c	16 Jul 2005 06:59:05 -0000	1.160
+++ win32/win32.c	22 Jul 2005 06:39:23 -0000
@@ -3600,4 +3600,5 @@ rb_w32_utime(const char *path, struct ut
 }
 
+#if 0
 int
 rb_w32_vsnprintf(char *buf, size_t size, const char *format, va_list va)
@@ -3619,4 +3620,5 @@ rb_w32_snprintf(char *buf, size_t size, 
     return ret;
 }
+#endif
 
 int
Index: win32/win32.h
===================================================================
RCS file: /cvs/ruby/src/ruby/win32/win32.h,v
retrieving revision 1.67
diff -U2 -p -r1.67 win32.h
--- win32/win32.h	16 Jul 2005 06:59:05 -0000	1.67
+++ win32/win32.h	22 Jul 2005 05:51:52 -0000
@@ -179,6 +179,8 @@ extern char **rb_w32_get_environ(void);
 extern void   rb_w32_free_environ(char **);
 
+#if 0
 #define vsnprintf(s,n,f,l) rb_w32_vsnprintf(s,n,f,l)
 #define snprintf   rb_w32_snprintf
+#endif
 extern int rb_w32_vsnprintf(char *, size_t, const char *, va_list);
 extern int rb_w32_snprintf(char *, size_t, const char *, ...);


-- 
--- 僕の前にBugはない。
--- 僕の後ろにBugはできる。
    中田 伸悦