Refactor pipe_read_line to return the full line Commit 5b2f4afffe6 refactored find_other_exec() and in the process created pipe_read_line() into a static routine for reading a single line of output, aimed at reading version numbers. Commit a7e8ece41 later exposed it externally in order to read a postgresql.conf GUC using "postgres -C ..". Further, f06b1c598 also made use of it for reading a version string much like find_other_exec(). The internal variable remained "pgver", even when used for other purposes.
Since the function requires passing a buffer and its size, and at most size - 1 bytes will be read via fgets(), there is a truncation risk when using this for reading GUCs (like how pg_rewind does, though the risk in this case is marginal). To keep this as generic functionality for reading a line from a pipe, this refactors pipe_read_line() into returning an allocated buffer containing all of the line to remove the risk of silent truncation. Reviewed-by: Heikki Linnakangas <[email protected]> Reviewed-by: Álvaro Herrera <[email protected]> Reviewed-by: John Naylor <[email protected]> Discussion: https://postgr.es/m/[email protected] Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/5c7038d70bb9c4d28a80b0a2051f73fafab5af3f Modified Files -------------- src/bin/pg_rewind/pg_rewind.c | 14 ++++++-------- src/bin/pg_upgrade/exec.c | 6 ++++-- src/common/exec.c | 39 +++++++++++++++++++++++++-------------- src/include/port.h | 2 +- 4 files changed, 36 insertions(+), 25 deletions(-)
