Re: [PATCH v3 1/9] am: stop ignoring errors reported by log_tree_diff()

[Junio C Hamano <gitster@pobox.com>]

Johannes Schindelin <johannes.schindelin@gmx.de> writes:

> Note: there are more places in the builtin am code that ignore
> errors returned from library functions. Fixing those is outside the
> purview of the current patch series, though.

The caller of parse_mail() and parse_mail_rebase() is not prepared
to see an error code in the returned value from these function,
which are to return a boolean telling the caller to skip or use the
patch file.  At least the caller needs to notice negative return and
made to die/exit(128), instead of silently skipping a corrupt or
unopenable patch, no?  Otherwise this will change the behaviour.

> Cc: Paul Tan <pyokagan@gmail.com>
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---
>  builtin/am.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/builtin/am.c b/builtin/am.c
> index 3dfe70b..0e28a62 100644
> --- a/builtin/am.c
> +++ b/builtin/am.c
> @@ -1433,12 +1433,15 @@ static void get_commit_info(struct am_state *state, struct commit *commit)
>  /**
>   * Writes `commit` as a patch to the state directory's "patch" file.
>   */
> -static void write_commit_patch(const struct am_state *state, struct commit *commit)
> +static int write_commit_patch(const struct am_state *state, struct commit *commit)
>  {
>  	struct rev_info rev_info;
>  	FILE *fp;
>  
> -	fp = xfopen(am_path(state, "patch"), "w");
> +	fp = fopen(am_path(state, "patch"), "w");
> +	if (!fp)
> +		return error(_("Could not open %s for writing"),
> +			am_path(state, "patch"));
>  	init_revisions(&rev_info, NULL);
>  	rev_info.diff = 1;
>  	rev_info.abbrev = 0;
> @@ -1453,7 +1456,7 @@ static void write_commit_patch(const struct am_state *state, struct commit *comm
>  	rev_info.diffopt.close_file = 1;
>  	add_pending_object(&rev_info, &commit->object, "");
>  	diff_setup_done(&rev_info.diffopt);
> -	log_tree_commit(&rev_info, commit);
> +	return log_tree_commit(&rev_info, commit);
>  }
>  
>  /**
> @@ -1501,13 +1504,14 @@ static int parse_mail_rebase(struct am_state *state, const char *mail)
>  	unsigned char commit_sha1[GIT_SHA1_RAWSZ];
>  
>  	if (get_mail_commit_sha1(commit_sha1, mail) < 0)
> -		die(_("could not parse %s"), mail);
> +		return error(_("could not parse %s"), mail);
>  
>  	commit = lookup_commit_or_die(commit_sha1, mail);
>  
>  	get_commit_info(state, commit);
>  
> -	write_commit_patch(state, commit);
> +	if (write_commit_patch(state, commit) < 0)
> +		return -1;
>  
>  	hashcpy(state->orig_commit, commit_sha1);
>  	write_state_text(state, "original-commit", sha1_to_hex(commit_sha1));