diff mbox series

[v5,03/13] bisect--helper: introduce new `write_in_file()` function

Message ID 20200717105406.82226-4-mirucam@gmail.com (mailing list archive)
State New, archived
Headers show
Series Finish converting git bisect to C part 2 | expand

Commit Message

Miriam R. July 17, 2020, 10:53 a.m. UTC 
Let's refactor code adding a new `write_in_file()` function
that opens a file for writing a message and closes it and a
wrapper for writing mode.

This helper will be used in later steps and makes the code
simpler and easier to understand.

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 builtin/bisect--helper.c | 41 +++++++++++++++++++++++++++++++++-------
 1 file changed, 34 insertions(+), 7 deletions(-)

Comments

Junio C Hamano July 17, 2020, 4:33 p.m. UTC | #1 
Miriam Rubio <mirucam@gmail.com> writes:

> +	fp = fopen(path, mode);
> +	if (!fp)
> +		return error_errno(_("cannot open file '%s' in mode '%s'"), path, mode);
> +	res = vfprintf(fp, format, args);
> +
> +	if (res < 0) {
> +		fclose(fp);
> +		return error_errno(_("could not write to file '%s'"), path);

If the fclose(fp) failed, the errno from that failure (i.e. why fp
cannot be closed) would be reported by the error_errno(), which may
not be ideal.  Either use just error() (which may be suboptimal),
follow an often-used pattern to use save_errno (grep for the symbol
to learn from the existing code) and keep using error_errno(), or
check errors from fclose() too (which may be overkill).

	if (res < 0) {
		int saved_errno = errno;
#if OVERKILL
		if (fclose(fp))
                	error_errno(_("..."));
#else
		fclose(fp);
#endif
		errno = saved_errno;
		return error_errno(_("..."), ...);
	}
diff mbox series

Patch

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 0466b07a43..d620d84d92 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -74,6 +74,38 @@  static int one_of(const char *term, ...)
 	return res;
 }
 
+static int write_in_file(const char *path, const char *mode, const char *format, va_list args)
+{
+	FILE *fp = NULL;
+	int res = 0;
+
+	if (strcmp(mode, "w"))
+		BUG("write-in-file does not support '%s' mode", mode);
+	fp = fopen(path, mode);
+	if (!fp)
+		return error_errno(_("cannot open file '%s' in mode '%s'"), path, mode);
+	res = vfprintf(fp, format, args);
+
+	if (res < 0) {
+		fclose(fp);
+		return error_errno(_("could not write to file '%s'"), path);
+	}
+
+	return fclose(fp);
+}
+
+static int write_to_file(const char *path, const char *format, ...)
+{
+	int res;
+	va_list args;
+
+	va_start(args, format);
+	res = write_in_file(path, "w", format, args);
+	va_end(args);
+
+	return res;
+}
+
 static int check_term_format(const char *term, const char *orig_term)
 {
 	int res;
@@ -104,7 +136,6 @@  static int check_term_format(const char *term, const char *orig_term)
 
 static int write_terms(const char *bad, const char *good)
 {
-	FILE *fp = NULL;
 	int res;
 
 	if (!strcmp(bad, good))
@@ -113,13 +144,9 @@  static int write_terms(const char *bad, const char *good)
 	if (check_term_format(bad, "bad") || check_term_format(good, "good"))
 		return -1;
 
-	fp = fopen(git_path_bisect_terms(), "w");
-	if (!fp)
-		return error_errno(_("could not open the file BISECT_TERMS"));
+	res = write_to_file(git_path_bisect_terms(), "%s\n%s\n", bad, good);
 
-	res = fprintf(fp, "%s\n%s\n", bad, good);
-	res |= fclose(fp);
-	return (res < 0) ? -1 : 0;
+	return res;
 }
 
 static int is_expected_rev(const char *expected_hex)