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comparison Objects/stringobject.c @ 17953:a429da7db706 2.1

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Net result of Tim's checkins to stropmodule.c (2.78, 2.79, 2.80, 2.81), stringobject.c (2.114, 2.115) and test_strop.py (1.11, 1.12). Fixes 'replace' behaviour on systems on which 'malloc(0)' returns NULL (together with previous checkins) and re-synchs the string-operation code in stringobject.c and stropmodule.c, with the exception of 'replace', which has the old semantics in stropmodule but the new semantics in stringobjects.
author Thomas Wouters <thomas@python.org>
date Wed, 23 May 2001 14:38:53 +0000
parents 5d894a5fce38
children ba6721ae4b80
comparison
equal deleted inserted replaced
17952:9dfd22e8e9b7 17953:a429da7db706
1529 static char * 1529 static char *
1530 mymemreplace(const char *str, int len, /* input string */ 1530 mymemreplace(const char *str, int len, /* input string */
1531 const char *pat, int pat_len, /* pattern string to find */ 1531 const char *pat, int pat_len, /* pattern string to find */
1532 const char *sub, int sub_len, /* substitution string */ 1532 const char *sub, int sub_len, /* substitution string */
1533 int count, /* number of replacements */ 1533 int count, /* number of replacements */
1534 int *out_len) 1534 int *out_len)
1535 { 1535 {
1536 char *out_s; 1536 char *out_s;
1537 char *new_s; 1537 char *new_s;
1538 int nfound, offset, new_len; 1538 int nfound, offset, new_len;
1539 1539
1546 count = INT_MAX; 1546 count = INT_MAX;
1547 else if (nfound > count) 1547 else if (nfound > count)
1548 nfound = count; 1548 nfound = count;
1549 if (nfound == 0) 1549 if (nfound == 0)
1550 goto return_same; 1550 goto return_same;
1551
1551 new_len = len + nfound*(sub_len - pat_len); 1552 new_len = len + nfound*(sub_len - pat_len);
1552 1553 if (new_len == 0) {
1553 new_s = (char *)PyMem_MALLOC(new_len); 1554 /* Have to allocate something for the caller to free(). */
1554 if (new_s == NULL) return NULL; 1555 out_s = (char *)PyMem_MALLOC(1);
1555 1556 if (out_s == NULL)
1557 return NULL;
1558 out_s[0] = '\0';
1559 }
1560 else {
1561 assert(new_len > 0);
1562 new_s = (char *)PyMem_MALLOC(new_len);
1563 if (new_s == NULL)
1564 return NULL;
1565 out_s = new_s;
1566
1567 for (; count > 0 && len > 0; --count) {
1568 /* find index of next instance of pattern */
1569 offset = mymemfind(str, len, pat, pat_len);
1570 if (offset == -1)
1571 break;
1572
1573 /* copy non matching part of input string */
1574 memcpy(new_s, str, offset);
1575 str += offset + pat_len;
1576 len -= offset + pat_len;
1577
1578 /* copy substitute into the output string */
1579 new_s += offset;
1580 memcpy(new_s, sub, sub_len);
1581 new_s += sub_len;
1582 }
1583 /* copy any remaining values into output string */
1584 if (len > 0)
1585 memcpy(new_s, str, len);
1586 }
1556 *out_len = new_len; 1587 *out_len = new_len;
1557 out_s = new_s;
1558
1559 while (len > 0) {
1560 /* find index of next instance of pattern */
1561 offset = mymemfind(str, len, pat, pat_len);
1562 /* if not found, break out of loop */
1563 if (offset == -1) break;
1564
1565 /* copy non matching part of input string */
1566 memcpy(new_s, str, offset); /* copy part of str before pat */
1567 str += offset + pat_len; /* move str past pattern */
1568 len -= offset + pat_len; /* reduce length of str remaining */
1569
1570 /* copy substitute into the output string */
1571 new_s += offset; /* move new_s to dest for sub string */
1572 memcpy(new_s, sub, sub_len); /* copy substring into new_s */
1573 new_s += sub_len; /* offset new_s past sub string */
1574
1575 /* break when we've done count replacements */
1576 if (--count == 0) break;
1577 }
1578 /* copy any remaining values into output string */
1579 if (len > 0)
1580 memcpy(new_s, str, len);
1581 return out_s; 1588 return out_s;
1582 1589
1583 return_same: 1590 return_same:
1584 *out_len = -1; 1591 *out_len = -1;
1585 return (char*)str; /* have to cast away constness here */ 1592 return (char *)str; /* cast away const */
1586 } 1593 }
1587 1594
1588 1595
1589 static char replace__doc__[] = 1596 static char replace__doc__[] =
1590 "S.replace (old, new[, maxsplit]) -> string\n\ 1597 "S.replace (old, new[, maxsplit]) -> string\n\