diff options
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); } |