Patch #479898: Use multibyte C library for printing strings if available.
diff --git a/Objects/stringobject.c b/Objects/stringobject.c
index 92adb49..c11a362 100644
--- a/Objects/stringobject.c
+++ b/Objects/stringobject.c
@@ -26,6 +26,19 @@
static PyObject *interned;
+#if defined(HAVE_MBTOWC) && defined(HAVE_WCHAR_H)
+# define PRINT_MULTIBYTE_STRING
+# include <locale.h>
+# include <wchar.h>
+# if defined(HAVE_ISWPRINT)
+# define _isprint iswprint
+# else
+# define _isprint isprint
+# endif
+#endif
+
+static const char *hexchars = "0123456789abcdef";
+
/*
For both PyString_FromString() and PyString_FromStringAndSize(), the
parameter `size' denotes number of characters to allocate, not counting any
@@ -749,8 +762,14 @@
static int
string_print(PyStringObject *op, FILE *fp, int flags)
{
+#ifndef PRINT_MULTIBYTE_STRING
int i;
char c;
+#else
+ char *scur, *send;
+ wchar_t c;
+ int cr;
+#endif
int quote;
/* XXX Ought to check for interrupts when writing long strings */
@@ -776,20 +795,36 @@
quote = '"';
fputc(quote, fp);
+#ifndef PRINT_MULTIBYTE_STRING
for (i = 0; i < op->ob_size; i++) {
c = op->ob_sval[i];
+#else
+ for (scur = op->ob_sval, send = op->ob_sval + op->ob_size;
+ scur < send; scur += cr) {
+ if ((cr = mbtowc(&c, scur, send - scur)) <= 0)
+ goto non_printable;
+#endif
if (c == quote || c == '\\')
- fprintf(fp, "\\%c", c);
+ fputc('\\', fp), fputc(c, fp);
else if (c == '\t')
- fprintf(fp, "\\t");
+ fputs("\\t", fp);
else if (c == '\n')
- fprintf(fp, "\\n");
+ fputs("\\n", fp);
else if (c == '\r')
- fprintf(fp, "\\r");
- else if (c < ' ' || c >= 0x7f)
- fprintf(fp, "\\x%02x", c & 0xff);
- else
+ fputs("\\r", fp);
+#ifndef PRINT_MULTIBYTE_STRING
+ else if (' ' <= c && c < 0x7f)
fputc(c, fp);
+ else
+ fprintf(fp, "\\x%02x", c & 0xff);
+#else
+ else if (_isprint(c))
+ fwrite(scur, cr, 1, fp);
+ else {
+non_printable: cr = 1; /* unit to move cursor */
+ fprintf(fp, "\\x%02x", *scur & 0xff);
+ }
+#endif
}
fputc(quote, fp);
return 0;
@@ -810,8 +845,14 @@
return NULL;
}
else {
+#ifndef PRINT_MULTIBYTE_STRING
register int i;
register char c;
+#else
+ register char *scur, *send;
+ wchar_t c;
+ int cr;
+#endif
register char *p;
int quote;
@@ -824,11 +865,18 @@
p = PyString_AS_STRING(v);
*p++ = quote;
+#ifndef PRINT_MULTIBYTE_STRING
for (i = 0; i < op->ob_size; i++) {
/* There's at least enough room for a hex escape
and a closing quote. */
assert(newsize - (p - PyString_AS_STRING(v)) >= 5);
c = op->ob_sval[i];
+#else
+ for (scur = op->ob_sval, send = op->ob_sval + op->ob_size;
+ scur < send; scur += cr) {
+ if ((cr = mbtowc(&c, scur, send - scur)) <= 0)
+ goto non_printable;
+#endif
if (c == quote || c == '\\')
*p++ = '\\', *p++ = c;
else if (c == '\t')
@@ -837,15 +885,20 @@
*p++ = '\\', *p++ = 'n';
else if (c == '\r')
*p++ = '\\', *p++ = 'r';
- else if (c < ' ' || c >= 0x7f) {
- /* For performance, we don't want to call
- PyOS_snprintf here (extra layers of
- function call). */
- sprintf(p, "\\x%02x", c & 0xff);
- p += 4;
- }
- else
+#ifndef PRINT_MULTIBYTE_STRING
+ else if (' ' <= c && c < 0x7f)
*p++ = c;
+ else {
+#else
+ else if (_isprint(c))
+ memcpy(p, scur, cr), p += cr;
+ else {
+non_printable: cr = 1; c = *scur;
+#endif
+ *p++ = '\\'; *p++ = 'x';
+ *p++ = hexchars[(c >> 4) & 0x0f];
+ *p++ = hexchars[c & 0x0f];
+ }
}
assert(newsize - (p - PyString_AS_STRING(v)) >= 1);
*p++ = quote;