diff options
| author | Michael Paquier <michael@paquier.xyz> | 2025-04-07 10:02:12 +0900 |
|---|---|---|
| committer | Michael Paquier <michael@paquier.xyz> | 2025-04-07 10:02:12 +0900 |
| commit | c36eda259130faf3559b751b9e81a5c7e2bee0d7 (patch) | |
| tree | ebf8847b980eea1bd53cd4c58cb9f5a8a990d167 /src/backend/utils/adt/quote.c | |
| parent | 3191a593d6dea56def460d06adc779f2aca44976 (diff) | |
| download | postgresql-c36eda259130faf3559b751b9e81a5c7e2bee0d7.tar.gz postgresql-c36eda259130faf3559b751b9e81a5c7e2bee0d7.zip | |
Clarify comment for worst-case allocation in quote_literal_cstr()
palloc() is invoked with a specific formula for its allocation size in
quote_literal_cstr(). This wastes some memory, but the size is large
enough to cover even the worst-case scenarios.
No explanations were given about the reasons behind these numbers. This
commit adds more documentation about all that.
Author: Steve Chavez <steve@supabase.io>
Discussion: https://postgr.es/m/CAGRrpzZ9bToRWS+fAnjxDJrxwZN1QcJ-y1Pn2yg=Hst6rydLtw@mail.gmail.com
Diffstat (limited to 'src/backend/utils/adt/quote.c')
| -rw-r--r-- | src/backend/utils/adt/quote.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/src/backend/utils/adt/quote.c b/src/backend/utils/adt/quote.c index 677efb93e8d..551de59a07f 100644 --- a/src/backend/utils/adt/quote.c +++ b/src/backend/utils/adt/quote.c @@ -108,7 +108,12 @@ quote_literal_cstr(const char *rawstr) len = strlen(rawstr); /* We make a worst-case result area; wasting a little space is OK */ - result = palloc(len * 2 + 3 + 1); + result = palloc( + (len * 2) /* doubling for every character if each one is + * a quote */ + + 3 /* two outer quotes + possibly 'E' if needed */ + + 1 /* null terminator */ + ); newlen = quote_literal_internal(result, rawstr, len); result[newlen] = '\0'; |