Module Name: src
Committed By: rillig
Date: Sat Jul 3 22:39:40 UTC 2021
Modified Files:
src/usr.bin/make/unit-tests: job-output-null.exp job-output-null.mk
Log Message:
tests/make: make test job-output-null more portable
Previously, the test dependend on implementation details of the system's
printf command.
Thank you sjg for the detailed analysis on macOS, FreeBSD and Linux.
To generate a diff of this commit:
cvs rdiff -u -r1.1 -r1.2 src/usr.bin/make/unit-tests/job-output-null.exp \
src/usr.bin/make/unit-tests/job-output-null.mk
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/unit-tests/job-output-null.exp
diff -u src/usr.bin/make/unit-tests/job-output-null.exp:1.1 src/usr.bin/make/unit-tests/job-output-null.exp:1.2
--- src/usr.bin/make/unit-tests/job-output-null.exp:1.1 Thu Apr 15 19:02:29 2021
+++ src/usr.bin/make/unit-tests/job-output-null.exp Sat Jul 3 22:39:40 2021
@@ -1,4 +1,4 @@
hello
hello
-hello world without newline, hello world without newline, hello world without newline.
+hello without newline, hello without newline.
exit status 0
Index: src/usr.bin/make/unit-tests/job-output-null.mk
diff -u src/usr.bin/make/unit-tests/job-output-null.mk:1.1 src/usr.bin/make/unit-tests/job-output-null.mk:1.2
--- src/usr.bin/make/unit-tests/job-output-null.mk:1.1 Thu Apr 15 19:02:29 2021
+++ src/usr.bin/make/unit-tests/job-output-null.mk Sat Jul 3 22:39:40 2021
@@ -1,4 +1,4 @@
-# $NetBSD: job-output-null.mk,v 1.1 2021/04/15 19:02:29 rillig Exp $
+# $NetBSD: job-output-null.mk,v 1.2 2021/07/03 22:39:40 rillig Exp $
#
# Test how null bytes in the output of a command are handled. Make processes
# them using null-terminated strings, which may cut off some of the output.
@@ -7,20 +7,33 @@
# inconsistently. It's an edge case though since typically the child
# processes output text.
+# Note: The printf commands used in this test must only use a single format
+# string, without parameters. This is because it is implementation-dependent
+# how many times the command 'printf "fmt%s" "" "" ""' calls write(2).
+#
+# NetBSD /bin/sh 1 x write("fmtfmtfmt")
+# Dash 1 x write("fmtfmtfmt")
+# NetBSD /bin/ksh 3 x write("fmt") (via /bin/printf)
+# Bash 5 3 x write("fmt")
+#
+# In the latter case the output may arrive in parts, which in this test makes
+# a crucial difference since the outcome of the test depends on whether there
+# is a '\n' in each of the blocks from the output.
+
.MAKEFLAGS: -j1 # force jobs mode
all: .PHONY
# The null byte from the command output is kept as-is.
# See CollectOutput, which looks like it intended to replace these
# null bytes with simple spaces.
- @printf 'hello\0world%s\n' ''
+ @printf 'hello\0world\n'
# Give the parent process a chance to see the above output, but not
# yet the output from the next printf command.
@sleep 1
# All null bytes from the command output are kept as-is.
- @printf 'hello\0world%s\n' '' '' '' '' '' ''
+ @printf 'hello\0world\n''hello\0world\n''hello\0world\n'
@sleep 1
@@ -29,4 +42,4 @@ all: .PHONY
#
# The three null bytes in a row test whether this output is
# compressed to a single space like in DebugFailedTarget. It isn't.
- @printf 'hello\0world\0without\0\0\0newline%s' ', ' ', ' '.'
+ @printf 'hello\0without\0\0\0newline, hello\0without\0\0\0newline.'
