hook: allow separate std[out|err] streams
The hook API assumes that all hooks merge stdout to stderr. This assumption is proven wrong by pre-push: some of its users actually expect separate stdout and stderr streams and merging them will cause a regression. Therefore this adds a mechanism to allow pre-push to separate the streams, which will be used in the next commit. The mechanism is generic via struct run_hooks_opt just in case there are any more surprise exceptions like this. Reported-by: Chris Darroch <chrisd@apache.org> Suggested-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adrian Ratiu committed
Jan 28, 2026 at 23:39 UTC
d816637f6c253e3829c4c6e817c7749b3a4f8bf4
2 files changed
+11
-1
hook.c
+1
-1
@@ -81,7 +81,7 @@ static int pick_next_hook(struct child_process *cp,
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cp->in = -1;
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}
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- cp->stdout_to_stderr = 1;
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+ cp->stdout_to_stderr = hook_cb->options->stdout_to_stderr;
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cp->trace2_hook_name = hook_cb->hook_name;
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cp->dir = hook_cb->options->dir;
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hook.h
+10
@@ -34,6 +34,15 @@ struct run_hooks_opt
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*/
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int *invoked_hook;
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+ /**
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+ * Send the hook's stdout to stderr.
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+ *
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+ * This is the default behavior for all hooks except pre-push,
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+ * which has separate stdout and stderr streams for backwards
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+ * compatibility reasons.
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+ */
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+ unsigned int stdout_to_stderr:1;
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+
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/**
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* Path to file which should be piped to stdin for each hook.
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*/
@@ -80,6 +89,7 @@ struct run_hooks_opt
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#define RUN_HOOKS_OPT_INIT { \
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.env = STRVEC_INIT, \
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.args = STRVEC_INIT, \
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+ .stdout_to_stderr = 1, \
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}
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struct hook_cb_data {