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| author | Noah Misch <noah@leadboat.com> | 2017-03-12 19:35:33 -0400 |
|---|---|---|
| committer | Noah Misch <noah@leadboat.com> | 2017-03-12 19:35:33 -0400 |
| commit | 9d7726c2ba06b932f791f2d0cc5acf73cc0b4dca (patch) | |
| tree | a67dc4573e6e89d07be29c41679ce821009df9a3 /src/tutorial | |
| parent | 944a026b4ec252667f275768ba4dcd53ae3bb07e (diff) | |
| download | postgresql-9d7726c2ba06b932f791f2d0cc5acf73cc0b4dca.tar.gz postgresql-9d7726c2ba06b932f791f2d0cc5acf73cc0b4dca.zip | |
Recommend wrappers of PG_DETOAST_DATUM_PACKED().
When commit 3e23b68dac006e8deb0afa327e855258df8de064 introduced
single-byte varlena headers, its fmgr.h changes presented
PG_GETARG_TEXT_PP() and PG_GETARG_TEXT_P() as equals. Its postgres.h
changes presented PG_DETOAST_DATUM_PACKED() and VARDATA_ANY() as the
exceptional case. Now, instead, firmly recommend PG_GETARG_TEXT_PP()
over PG_GETARG_TEXT_P(); likewise for other ...PP() macros. This shaves
cycles and invites consistency of style.
Diffstat (limited to 'src/tutorial')
| -rw-r--r-- | src/tutorial/funcs_new.c | 29 |
1 files changed, 16 insertions, 13 deletions
diff --git a/src/tutorial/funcs_new.c b/src/tutorial/funcs_new.c index f668d281bb1..2e09f8de6e7 100644 --- a/src/tutorial/funcs_new.c +++ b/src/tutorial/funcs_new.c @@ -66,21 +66,24 @@ PG_FUNCTION_INFO_V1(copytext); Datum copytext(PG_FUNCTION_ARGS) { - text *t = PG_GETARG_TEXT_P(0); + text *t = PG_GETARG_TEXT_PP(0); /* - * VARSIZE is the total size of the struct in bytes. + * VARSIZE_ANY_EXHDR is the size of the struct in bytes, minus the + * VARHDRSZ or VARHDRSZ_SHORT of its header. Construct the copy with a + * full-length header. */ - text *new_t = (text *) palloc(VARSIZE(t)); + text *new_t = (text *) palloc(VARSIZE_ANY_EXHDR(t) + VARHDRSZ); - SET_VARSIZE(new_t, VARSIZE(t)); + SET_VARSIZE(new_t, VARSIZE_ANY_EXHDR(t) + VARHDRSZ); /* - * VARDATA is a pointer to the data region of the struct. + * VARDATA is a pointer to the data region of the new struct. The source + * could be a short datum, so retrieve its data through VARDATA_ANY. */ memcpy((void *) VARDATA(new_t), /* destination */ - (void *) VARDATA(t), /* source */ - VARSIZE(t) - VARHDRSZ); /* how many bytes */ + (void *) VARDATA_ANY(t), /* source */ + VARSIZE_ANY_EXHDR(t)); /* how many bytes */ PG_RETURN_TEXT_P(new_t); } @@ -89,16 +92,16 @@ PG_FUNCTION_INFO_V1(concat_text); Datum concat_text(PG_FUNCTION_ARGS) { - text *arg1 = PG_GETARG_TEXT_P(0); - text *arg2 = PG_GETARG_TEXT_P(1); - int32 arg1_size = VARSIZE(arg1) - VARHDRSZ; - int32 arg2_size = VARSIZE(arg2) - VARHDRSZ; + text *arg1 = PG_GETARG_TEXT_PP(0); + text *arg2 = PG_GETARG_TEXT_PP(1); + int32 arg1_size = VARSIZE_ANY_EXHDR(arg1); + int32 arg2_size = VARSIZE_ANY_EXHDR(arg2); int32 new_text_size = arg1_size + arg2_size + VARHDRSZ; text *new_text = (text *) palloc(new_text_size); SET_VARSIZE(new_text, new_text_size); - memcpy(VARDATA(new_text), VARDATA(arg1), arg1_size); - memcpy(VARDATA(new_text) + arg1_size, VARDATA(arg2), arg2_size); + memcpy(VARDATA(new_text), VARDATA_ANY(arg1), arg1_size); + memcpy(VARDATA(new_text) + arg1_size, VARDATA_ANY(arg2), arg2_size); PG_RETURN_TEXT_P(new_text); } |