"Tom Lane" <[EMAIL PROTECTED]> writes: > Gregory Stark <[EMAIL PROTECTED]> writes: >> 1) Replace the VARATT_SIZEP macro with SET_VARLENA_LEN. > > If we're going to do this then it's time to play the name game;
Least...fun...game...evar... > A first-cut proposal: > > VARHDRSZ same as now, ie, size of 4-byte header > VARSIZE(x) for *reading* a 4-byte-header length word > VARDATA(x) same as now, ie, ptr + 4 bytes > SET_VARSIZE(x, len) for *writing* a 4-byte-header length word There's also VARATT_CDATA which I suppose I should rename to VARCDATA. I may not even need it once I hit tuptoaster.c since that file works directly with the structure members anyways. I supposed we also rename VARATT_IS_{COMPRESSED,EXTERNAL,EXTENDED} ? Is VAR_IS_* ok or does that sound too generic? > We'll also need names for the macros that can read the length and find > the data of a datum in either-1-or-4-byte-header format. These should > probably be named as variants of VARSIZE and VARDATA, but I'm not sure > what exactly; any thoughts? I can't think of any good names for the "automatic" macros. Right now I have VARSIZE_ANY(ptr) but that doesn't seem particularly pleasing. For the internal macros for each specific size I have: #define VARDATA_4B(PTR) ((PTR)->va_4byte.va_data) #define VARDATA_2B(PTR) ((PTR)->va_2byte.va_data) #define VARDATA_1B(PTR) ((PTR)->va_1byte.va_data) #define VARSIZE_IS_4B(PTR) ((PTR)->va_1byte.va_header & ~0x3F == 0x00) #define VARSIZE_IS_2B(PTR) ((PTR)->va_1byte.va_header & ~0x1F == 0x20) #define VARSIZE_IS_1B(PTR) ((PTR)->va_1byte.va_header & ~0x7F == 0x80) #define VARSIZE_4B(PTR) (ntohl((PTR)->va_4byte.va_header) & 0x3FFFFFFF) #define VARSIZE_2B(PTR) (ntohs((PTR)->va_2byte.va_header) & 0x1FFF) #define VARSIZE_1B(PTR) ( ((PTR)->va_1byte.va_header) & 0x7F) #define SET_VARSIZE_4B(PTR,len) ((PTR)->va_4byte.va_header = htonl(len)) #define SET_VARSIZE_2B(PTR,len) ((PTR)->va_2byte.va_header = htons((len) | 0x2000)) #define SET_VARSIZE_1B(PTR,len) ((PTR)->va_1byte.va_header = (len) | 0x80) I had a separate version for little-endian but it was driving me nuts having two versions to keep tweaking. I also had the magic constants as #defines but it really didn't enhance readability at all so I took them out when I rewrote this just now. Incidentally I profiled htonl against a right shift on my machine (an intel 2Ghz core duo). htonl is four times slower but that's 3.2ns versus 0.8ns. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly