diff options
Diffstat (limited to 'src/backend/utils/adt/regexp.c')
| -rw-r--r-- | src/backend/utils/adt/regexp.c | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/src/backend/utils/adt/regexp.c b/src/backend/utils/adt/regexp.c index edee1f7880b..6e2864cbbda 100644 --- a/src/backend/utils/adt/regexp.c +++ b/src/backend/utils/adt/regexp.c @@ -773,8 +773,11 @@ similar_escape_internal(text *pat_text, text *esc_text) int plen, elen; bool afterescape = false; - bool incharclass = false; int nquotes = 0; + int charclass_depth = 0; /* Nesting level of character classes, + * encompassed by square brackets */ + int charclass_start = 0; /* State of the character class start, + * for carets */ p = VARDATA_ANY(pat_text); plen = VARSIZE_ANY_EXHDR(pat_text); @@ -904,7 +907,7 @@ similar_escape_internal(text *pat_text, text *esc_text) /* fast path */ if (afterescape) { - if (pchar == '"' && !incharclass) /* escape-double-quote? */ + if (pchar == '"' && charclass_depth < 1) /* escape-double-quote? */ { /* emit appropriate part separator, per notes above */ if (nquotes == 0) @@ -953,18 +956,41 @@ similar_escape_internal(text *pat_text, text *esc_text) /* SQL escape character; do not send to output */ afterescape = true; } - else if (incharclass) + else if (charclass_depth > 0) { if (pchar == '\\') *r++ = '\\'; *r++ = pchar; - if (pchar == ']') - incharclass = false; + + /* + * Ignore a closing bracket at the start of a character class. + * Such a bracket is taken literally rather than closing the + * class. "charclass_start" is 1 right at the beginning of a + * class and 2 after an initial caret. + */ + if (pchar == ']' && charclass_start > 2) + charclass_depth--; + else if (pchar == '[') + charclass_depth++; + + /* + * If there is a caret right after the opening bracket, it negates + * the character class, but a following closing bracket should + * still be treated as a normal character. That holds only for + * the first caret, so only the values 1 and 2 mean that closing + * brackets should be taken literally. + */ + if (pchar == '^') + charclass_start++; + else + charclass_start = 3; /* definitely past the start */ } else if (pchar == '[') { + /* start of a character class */ *r++ = pchar; - incharclass = true; + charclass_depth++; + charclass_start = 1; } else if (pchar == '%') { |