There are many callsites which could use write_file, but for
which it is a little awkward because they have a strbuf or
other pointer/len combo. Specifically:
1. write_file() takes a format string, so we have to use
"%s" or "%.*s", which are ugly.
2. Using any form of "%s" does not handle embedded NULs in
the output. That probably doesn't matter for our
call-sites, but it's nicer not to have to worry.
3. It's less efficient; we format into another strbuf
just to do the write. That's probably not measurably
slow for our uses, but it's simply inelegant.
We can fix this by providing a helper to write out the
formatted buffer, and just calling it from write_file().
Note that we don't do the usual "complete with a newline"
that write_file does. If the caller has their own buffer,
there's a reasonable chance they're doing something more
complicated than a single line, and they can call
strbuf_complete_line() themselves.
We could go even further and add strbuf_write_file(), but it
doesn't save much:
- write_file_buf(path, sb.buf, sb.len);
+ strbuf_write_file(&sb, path);
It would also be somewhat asymmetric with strbuf_read_file,
which actually returns errors rather than dying (and the
error handling is most of the benefit of write_file() in the
first place).
Signed-off-by: Jeff King <peff@xxxxxxxx>
---
cache.h | 6 ++++++
wrapper.c | 16 +++++++++++-----
2 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/cache.h b/cache.h
index 3f6c53f..9d6ad4f 100644
--- a/cache.h
+++ b/cache.h
@@ -1745,6 +1745,12 @@ static inline ssize_t write_str_in_full(int fd, const char *str)
return write_in_full(fd, str, strlen(str));
}
+/**
+ * Open (and truncate) the file at path, write the contents of buf to it,
+ * and close it. Dies if any errors are encountered.
+ */
+extern void write_file_buf(const char *path, const char *buf, size_t len);
+
extern void write_file(const char *path, const char *fmt, ...);
/* pager.c */
diff --git a/wrapper.c b/wrapper.c
index 7c126b8..b827206 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -640,22 +640,28 @@ int xsnprintf(char *dst, size_t max, const char *fmt, ...)
return len;
}
+void write_file_buf(const char *path, const char *buf, size_t len)
+{
+ int fd = xopen(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+ if (write_in_full(fd, buf, len) != len)
+ die_errno(_("could not write to %s"), path);
+ if (close(fd))
+ die_errno(_("could not close %s"), path);
+}
+
void write_file(const char *path, const char *fmt, ...)
{
va_list params;
struct strbuf sb = STRBUF_INIT;
- int fd = xopen(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
va_start(params, fmt);
strbuf_vaddf(&sb, fmt, params);
va_end(params);
strbuf_complete_line(&sb);
- if (write_in_full(fd, sb.buf, sb.len) != sb.len)
- die_errno(_("could not write to %s"), path);
+
+ write_file_buf(path, sb.buf, sb.len);
strbuf_release(&sb);
- if (close(fd))
- die_errno(_("could not close %s"), path);
}
void sleep_millisec(int millisec)
--
2.9.0.393.g704e522
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html