Module Name: src
Committed By: christos
Date: Mon May 9 21:25:11 UTC 2016
Modified Files:
src/lib/libedit: readline.c
Log Message:
The libedit implementation of history_get() also differs from the GNU
implementation: libedit goes to the entry with the given number
stored in the HistEvent structure, while GNU subtracts history_base,
then advances that many entries from the oldest one. If entries were
removed in between, GNU advances further than libedit.
The call sequence H_CURR, H_DELDATA, H_CURR, H_NEXT_EVDATA looks
weird, as if part of that must somehow be redundant. But actually,
the user interface is so counter-intuitive that every single step
is really required.
- The first H_CURR is needed to be able to go back after an error.
- The H_DELDATA is needed to move the cursor. Even though it takes
a pointer to ev, that structure is not filled in when the call
succeeds. H_DELDATA only moves the cursor, it doesn't tell us
the new event number.
- Consequently, the second H_CURR is required to get ev.num filled
in. But it doesn't return the data because ev has no field for
that.
- So even though the cursor is already positioned correctly,
H_NEXT_EVDATA is needed as the final step merely to get the data.
(Ingo Schwarze)
To generate a diff of this commit:
cvs rdiff -u -r1.130 -r1.131 src/lib/libedit/readline.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
