diff options
Diffstat (limited to 'src/backend/utils/mb/mbutils.c')
| -rw-r--r-- | src/backend/utils/mb/mbutils.c | 79 |
1 files changed, 69 insertions, 10 deletions
diff --git a/src/backend/utils/mb/mbutils.c b/src/backend/utils/mb/mbutils.c index 2578573b0ab..a13c398f4ac 100644 --- a/src/backend/utils/mb/mbutils.c +++ b/src/backend/utils/mb/mbutils.c @@ -406,12 +406,13 @@ pg_do_encoding_conversion(unsigned char *src, int len, MemoryContextAllocHuge(CurrentMemoryContext, (Size) len * MAX_CONVERSION_GROWTH + 1); - OidFunctionCall5(proc, - Int32GetDatum(src_encoding), - Int32GetDatum(dest_encoding), - CStringGetDatum(src), - CStringGetDatum(result), - Int32GetDatum(len)); + (void) OidFunctionCall6(proc, + Int32GetDatum(src_encoding), + Int32GetDatum(dest_encoding), + CStringGetDatum(src), + CStringGetDatum(result), + Int32GetDatum(len), + BoolGetDatum(false)); /* * If the result is large, it's worth repalloc'ing to release any extra @@ -436,6 +437,62 @@ pg_do_encoding_conversion(unsigned char *src, int len, } /* + * Convert src string to another encoding. + * + * This function has a different API than the other conversion functions. + * The caller should've looked up the conversion function using + * FindDefaultConversionProc(). Unlike the other functions, the converted + * result is not palloc'd. It is written to the caller-supplied buffer + * instead. + * + * src_encoding - encoding to convert from + * dest_encoding - encoding to convert to + * src, srclen - input buffer and its length in bytes + * dest, destlen - destination buffer and its size in bytes + * + * The output is null-terminated. + * + * If destlen < srclen * MAX_CONVERSION_LENGTH + 1, the converted output + * wouldn't necessarily fit in the output buffer, and the function will not + * convert the whole input. + * + * TODO: The conversion function interface is not great. Firstly, it + * would be nice to pass through the destination buffer size to the + * conversion function, so that if you pass a shorter destination buffer, it + * could still continue to fill up the whole buffer. Currently, we have to + * assume worst case expansion and stop the conversion short, even if there + * is in fact space left in the destination buffer. Secondly, it would be + * nice to return the number of bytes written to the caller, to avoid a call + * to strlen(). + */ +int +pg_do_encoding_conversion_buf(Oid proc, + int src_encoding, + int dest_encoding, + unsigned char *src, int srclen, + unsigned char *dest, int destlen, + bool noError) +{ + Datum result; + + /* + * If the destination buffer is not large enough to hold the result in the + * worst case, limit the input size passed to the conversion function. + */ + if ((Size) srclen >= ((destlen - 1) / (Size) MAX_CONVERSION_GROWTH)) + srclen = ((destlen - 1) / (Size) MAX_CONVERSION_GROWTH); + + result = OidFunctionCall6(proc, + Int32GetDatum(src_encoding), + Int32GetDatum(dest_encoding), + CStringGetDatum(src), + CStringGetDatum(dest), + Int32GetDatum(srclen), + BoolGetDatum(noError)); + return DatumGetInt32(result); +} + +/* * Convert string to encoding encoding_name. The source * encoding is the DB encoding. * @@ -762,12 +819,13 @@ perform_default_encoding_conversion(const char *src, int len, MemoryContextAllocHuge(CurrentMemoryContext, (Size) len * MAX_CONVERSION_GROWTH + 1); - FunctionCall5(flinfo, + FunctionCall6(flinfo, Int32GetDatum(src_encoding), Int32GetDatum(dest_encoding), CStringGetDatum(src), CStringGetDatum(result), - Int32GetDatum(len)); + Int32GetDatum(len), + BoolGetDatum(false)); /* * Release extra space if there might be a lot --- see comments in @@ -849,12 +907,13 @@ pg_unicode_to_server(pg_wchar c, unsigned char *s) c_as_utf8[c_as_utf8_len] = '\0'; /* Convert, or throw error if we can't */ - FunctionCall5(Utf8ToServerConvProc, + FunctionCall6(Utf8ToServerConvProc, Int32GetDatum(PG_UTF8), Int32GetDatum(server_encoding), CStringGetDatum(c_as_utf8), CStringGetDatum(s), - Int32GetDatum(c_as_utf8_len)); + Int32GetDatum(c_as_utf8_len), + BoolGetDatum(false)); } |