Issue #7330: Implement width and precision (ex: "%5.3s") for the format string
of PyUnicode_FromFormat() function, original patch written by Ysj Ray.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 4c532af..795c18f 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -2346,6 +2346,67 @@
plus 1 for the sign. 53/22 is an upper bound for log10(256). */
#define MAX_LONG_LONG_CHARS (2 + (SIZEOF_LONG_LONG*53-1) / 22)
+static int
+unicode_fromformat_write_str(_PyUnicodeWriter *writer, PyObject *str,
+ Py_ssize_t width, Py_ssize_t precision)
+{
+ Py_ssize_t length, fill, arglen;
+ Py_UCS4 maxchar;
+
+ if (PyUnicode_READY(str) == -1)
+ return -1;
+
+ length = PyUnicode_GET_LENGTH(str);
+ if ((precision == -1 || precision >= length)
+ && width <= length)
+ return _PyUnicodeWriter_WriteStr(writer, str);
+
+ if (precision != -1)
+ length = Py_MIN(precision, length);
+
+ arglen = Py_MAX(length, width);
+ if (PyUnicode_MAX_CHAR_VALUE(str) > writer->maxchar)
+ maxchar = _PyUnicode_FindMaxChar(str, 0, length);
+ else
+ maxchar = writer->maxchar;
+
+ if (_PyUnicodeWriter_Prepare(writer, arglen, maxchar) == -1)
+ return -1;
+
+ if (width > length) {
+ fill = width - length;
+ if (PyUnicode_Fill(writer->buffer, writer->pos, fill, ' ') == -1)
+ return -1;
+ writer->pos += fill;
+ }
+
+ _PyUnicode_FastCopyCharacters(writer->buffer, writer->pos,
+ str, 0, length);
+ writer->pos += length;
+ return 0;
+}
+
+static int
+unicode_fromformat_write_cstr(_PyUnicodeWriter *writer, const char *str,
+ Py_ssize_t width, Py_ssize_t precision)
+{
+ /* UTF-8 */
+ Py_ssize_t length;
+ PyObject *unicode;
+ int res;
+
+ length = strlen(str);
+ if (precision != -1)
+ length = Py_MIN(length, precision);
+ unicode = PyUnicode_DecodeUTF8Stateful(str, length, "replace", NULL);
+ if (unicode == NULL)
+ return -1;
+
+ res = unicode_fromformat_write_str(writer, unicode, width, -1);
+ Py_DECREF(unicode);
+ return res;
+}
+
static const char*
unicode_fromformat_arg(_PyUnicodeWriter *writer,
const char *f, va_list *vargs)
@@ -2353,12 +2414,12 @@
const char *p;
Py_ssize_t len;
int zeropad;
- int width;
- int precision;
+ Py_ssize_t width;
+ Py_ssize_t precision;
int longflag;
int longlongflag;
int size_tflag;
- int fill;
+ Py_ssize_t fill;
p = f;
f++;
@@ -2369,28 +2430,36 @@
}
/* parse the width.precision part, e.g. "%2.5s" => width=2, precision=5 */
- width = 0;
- while (Py_ISDIGIT((unsigned)*f)) {
- if (width > (INT_MAX - ((int)*f - '0')) / 10) {
- PyErr_SetString(PyExc_ValueError,
- "width too big");
- return NULL;
- }
- width = (width*10) + (*f - '0');
- f++;
- }
- precision = 0;
- if (*f == '.') {
+ width = -1;
+ if (Py_ISDIGIT((unsigned)*f)) {
+ width = *f - '0';
f++;
while (Py_ISDIGIT((unsigned)*f)) {
- if (precision > (INT_MAX - ((int)*f - '0')) / 10) {
+ if (width > (PY_SSIZE_T_MAX - ((int)*f - '0')) / 10) {
PyErr_SetString(PyExc_ValueError,
- "precision too big");
+ "width too big");
return NULL;
}
- precision = (precision*10) + (*f - '0');
+ width = (width * 10) + (*f - '0');
f++;
}
+ }
+ precision = -1;
+ if (*f == '.') {
+ f++;
+ if (Py_ISDIGIT((unsigned)*f)) {
+ precision = (*f - '0');
+ f++;
+ while (Py_ISDIGIT((unsigned)*f)) {
+ if (precision > (PY_SSIZE_T_MAX - ((int)*f - '0')) / 10) {
+ PyErr_SetString(PyExc_ValueError,
+ "precision too big");
+ return NULL;
+ }
+ precision = (precision * 10) + (*f - '0');
+ f++;
+ }
+ }
if (*f == '%') {
/* "%.3%s" => f points to "3" */
f--;
@@ -2449,6 +2518,7 @@
/* used by sprintf */
char fmt[10]; /* should be enough for "%0lld\0" */
char buffer[MAX_LONG_LONG_CHARS];
+ Py_ssize_t arglen;
if (*f == 'u') {
makefmt(fmt, longflag, longlongflag, size_tflag, *f);
@@ -2494,26 +2564,29 @@
if (precision < len)
precision = len;
+
+ arglen = Py_MAX(precision, width);
+ assert(ucs1lib_find_max_char((Py_UCS1*)buffer, (Py_UCS1*)buffer + len) <= 127);
+ if (_PyUnicodeWriter_Prepare(writer, arglen, 127) == -1)
+ return NULL;
+
if (width > precision) {
Py_UCS4 fillchar;
fill = width - precision;
fillchar = zeropad?'0':' ';
- if (_PyUnicodeWriter_Prepare(writer, fill, fillchar) == -1)
- return NULL;
if (PyUnicode_Fill(writer->buffer, writer->pos, fill, fillchar) == -1)
return NULL;
writer->pos += fill;
}
if (precision > len) {
fill = precision - len;
- if (_PyUnicodeWriter_Prepare(writer, fill, '0') == -1)
- return NULL;
if (PyUnicode_Fill(writer->buffer, writer->pos, fill, '0') == -1)
return NULL;
writer->pos += fill;
}
- if (_PyUnicodeWriter_WriteCstr(writer, buffer, len) == -1)
- return NULL;
+
+ unicode_write_cstr(writer->buffer, writer->pos, buffer, len);
+ writer->pos += len;
break;
}
@@ -2535,8 +2608,11 @@
len += 2;
}
- if (_PyUnicodeWriter_WriteCstr(writer, number, len) == -1)
+ assert(ucs1lib_find_max_char((Py_UCS1*)number, (Py_UCS1*)number + len) <= 127);
+ if (_PyUnicodeWriter_Prepare(writer, len, 127) == -1)
return NULL;
+ unicode_write_cstr(writer->buffer, writer->pos, number, len);
+ writer->pos += len;
break;
}
@@ -2544,14 +2620,8 @@
{
/* UTF-8 */
const char *s = va_arg(*vargs, const char*);
- PyObject *str = PyUnicode_DecodeUTF8Stateful(s, strlen(s), "replace", NULL);
- if (!str)
+ if (unicode_fromformat_write_cstr(writer, s, width, precision) < 0)
return NULL;
- if (_PyUnicodeWriter_WriteStr(writer, str) == -1) {
- Py_DECREF(str);
- return NULL;
- }
- Py_DECREF(str);
break;
}
@@ -2560,7 +2630,7 @@
PyObject *obj = va_arg(*vargs, PyObject *);
assert(obj && _PyUnicode_CHECK(obj));
- if (_PyUnicodeWriter_WriteStr(writer, obj) == -1)
+ if (unicode_fromformat_write_str(writer, obj, width, precision) == -1)
return NULL;
break;
}
@@ -2569,22 +2639,15 @@
{
PyObject *obj = va_arg(*vargs, PyObject *);
const char *str = va_arg(*vargs, const char *);
- PyObject *str_obj;
- assert(obj || str);
if (obj) {
assert(_PyUnicode_CHECK(obj));
- if (_PyUnicodeWriter_WriteStr(writer, obj) == -1)
+ if (unicode_fromformat_write_str(writer, obj, width, precision) == -1)
return NULL;
}
else {
- str_obj = PyUnicode_DecodeUTF8Stateful(str, strlen(str), "replace", NULL);
- if (!str_obj)
+ assert(str != NULL);
+ if (unicode_fromformat_write_cstr(writer, str, width, precision) < 0)
return NULL;
- if (_PyUnicodeWriter_WriteStr(writer, str_obj) == -1) {
- Py_DECREF(str_obj);
- return NULL;
- }
- Py_DECREF(str_obj);
}
break;
}
@@ -2597,7 +2660,7 @@
str = PyObject_Str(obj);
if (!str)
return NULL;
- if (_PyUnicodeWriter_WriteStr(writer, str) == -1) {
+ if (unicode_fromformat_write_str(writer, str, width, precision) == -1) {
Py_DECREF(str);
return NULL;
}
@@ -2613,7 +2676,7 @@
repr = PyObject_Repr(obj);
if (!repr)
return NULL;
- if (_PyUnicodeWriter_WriteStr(writer, repr) == -1) {
+ if (unicode_fromformat_write_str(writer, repr, width, precision) == -1) {
Py_DECREF(repr);
return NULL;
}
@@ -2629,7 +2692,7 @@
ascii = PyObject_ASCII(obj);
if (!ascii)
return NULL;
- if (_PyUnicodeWriter_WriteStr(writer, ascii) == -1) {
+ if (unicode_fromformat_write_str(writer, ascii, width, precision) == -1) {
Py_DECREF(ascii);
return NULL;
}