From 3abcc79c6a25fe9846be5a036d9a44086fb00163 Mon Sep 17 00:00:00 2001 From: Martin Tournoij Date: Fri, 19 Apr 2024 15:11:30 -0600 Subject: [PATCH] head: use getline() instead of fgetln() This replaces fgetln() with getline(). The main reason for this is portability, making things easier for people who want to compile these tools on non-FreeBSD systems. I appreciate that's probably not the top concern for FreeBSD base tools, but fgetln() is impossible to port to most platforms, as concurrent access is essentially impossible to implement fully correct without the line buffer on the FILE struct. Other than this, many generic FreeBSD tools compile fairly cleanly on Linux with a few small changes. Most uses of fgetln() pre-date getline() support (added in 2009 with 69099ba2ec8b), and there's been some previous patches (ee3ca711a898 8c98e6b1a7f3 1a2a4fc8ce1b) for other tools. Obtained from: https://github.com/dcantrell/bsdutils and https://github.com/chimera-linux/chimerautils Signed-off-by: Martin Tournoij Reviewed by: imp Pull Request: https://github.com/freebsd/freebsd-src/pull/893 --- usr.bin/head/head.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/usr.bin/head/head.c b/usr.bin/head/head.c index 598d54b1c1ed..62796ae144a1 100644 --- a/usr.bin/head/head.c +++ b/usr.bin/head/head.c @@ -156,12 +156,13 @@ main(int argc, char *argv[]) static void head(FILE *fp, intmax_t cnt) { - char *cp; - size_t error, readlen; + char *cp = NULL; + size_t error, bufsize = 0; + ssize_t readlen; - while (cnt != 0 && (cp = fgetln(fp, &readlen)) != NULL) { + while (cnt != 0 && (readlen = getline(&cp, &bufsize, fp)) >= 0) { error = fwrite(cp, sizeof(char), readlen, stdout); - if (error != readlen) + if ((ssize_t)error != readlen) err(1, "stdout"); cnt--; }