path: root/t/helper
diff options
authorJohannes Schindelin <>2019-02-14 21:33:12 (GMT)
committerJunio C Hamano <>2019-02-19 18:22:21 (GMT)
commitd5cfd142ec1425cec44a7c74a42e5b81112460c3 (patch)
treee5755731b204245f589156762ce827ed5f706886 /t/helper
parentd99194822b8d8d3c7c2c8985b720b0e6a5542263 (diff)
tests: teach the test-tool to generate NUL bytes and use it
In cc95bc2025 (t5562: replace /dev/zero with a pipe from generate_zero_bytes, 2019-02-09), we replaced usage of /dev/zero (which is not available on NonStop, apparently) by a Perl script snippet to generate NUL bytes. Sadly, it does not seem to work on NonStop, as t5562 reportedly hangs. Worse, this also hangs in the Ubuntu 16.04 agents of the CI builds on Azure Pipelines: for some reason, the Perl script snippet that is run via `generate_zero_bytes` in t5562's 'CONTENT_LENGTH overflow ssite_t' test case tries to write out an infinite amount of NUL bytes unless a broken pipe is encountered, that snippet never encounters the broken pipe, and keeps going until the build times out. Oddly enough, this does not reproduce on the Windows and macOS agents, nor in a local Ubuntu 18.04. This developer tried for a day to figure out the exact circumstances under which this hang happens, to no avail, the details remain a mystery. In the end, though, what counts is that this here change incidentally fixes that hang (maybe also on NonStop?). Even more positively, it gets rid of yet another unnecessary Perl invocation. Signed-off-by: Johannes Schindelin <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 't/helper')
3 files changed, 23 insertions, 0 deletions
diff --git a/t/helper/test-genzeros.c b/t/helper/test-genzeros.c
new file mode 100644
index 0000000..9532f5b
--- /dev/null
+++ b/t/helper/test-genzeros.c
@@ -0,0 +1,21 @@
+#include "test-tool.h"
+#include "git-compat-util.h"
+int cmd__genzeros(int argc, const char **argv)
+ long count;
+ if (argc > 2) {
+ fprintf(stderr, "usage: %s [<count>]\n", argv[0]);
+ return 1;
+ }
+ count = argc > 1 ? strtol(argv[1], NULL, 0) : -1L;
+ while (count < 0 || count--) {
+ if (putchar(0) == EOF)
+ return -1;
+ }
+ return 0;
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index 50c55f8..99db740 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -19,6 +19,7 @@ static struct test_cmd cmds[] = {
{ "dump-untracked-cache", cmd__dump_untracked_cache },
{ "example-decorate", cmd__example_decorate },
{ "genrandom", cmd__genrandom },
+ { "genzeros", cmd__genzeros },
{ "hashmap", cmd__hashmap },
{ "hash-speed", cmd__hash_speed },
{ "index-version", cmd__index_version },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index a563df4..25abed1 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -16,6 +16,7 @@ int cmd__dump_split_index(int argc, const char **argv);
int cmd__dump_untracked_cache(int argc, const char **argv);
int cmd__example_decorate(int argc, const char **argv);
int cmd__genrandom(int argc, const char **argv);
+int cmd__genzeros(int argc, const char **argv);
int cmd__hashmap(int argc, const char **argv);
int cmd__hash_speed(int argc, const char **argv);
int cmd__index_version(int argc, const char **argv);